OnCo

Pathway-to-drug matrix

The pathway diagrams light up per product; this table asks the inverse question. Across 86 pathways and 724 nodes, 182 nodes name a target in the corpus, 163 of those have at least one product and 19 have none. Pathways are sorted by how many druggable nodes still have no drug, which is where the design opportunities are.

PathwayNodesWith a targetWith a drugApproved drugUndrugged
Synthetic lethality: paired dependencies137334
DNA replication stress94222
p53 / RB / cell-cycle checkpoint104222
The p53 network (guardian of the genome)94222
Double-strand break repair: HR versus end joining104331
Nutrient competition & metabolic immunosuppression94331
The cell-cycle engine (cyclins & CDKs)104331
Transcriptional machinery & addiction94331
DNA damage response & homologous recombination93221
Ubiquitin–proteasome system & protein homeostasis103221
Mismatch repair & microsatellite instability102111
Circadian control61001
Telomere maintenance & replicative immortality61001
Cold tumours: immune deserts and exclusion106640
Resistance routes: how a blocked pathway comes back96660
Lineage plasticity & neuroendocrine transformation95540
Receptor tyrosine kinase activation95550
Tumour microenvironment (TME)95530
Fibroblast activation, desmoplasia & matrix stiffness104430
Glutamine addiction104440
Myeloid suppression: TAMs, MDSCs & don't-eat-me signals104430
PD-1 / PD-L1 immune checkpoint & T-cell activation104440
Complement in cancer103330
DNA replication & origin licensing103330
Drug-tolerant persister cells103320
Epigenetic reprogramming73320
FGF / FGFR signalling83330
Mitosis & the spindle assembly checkpoint103330
Oncogenic viruses103330
PI3K / AKT / mTOR93330
RAS / RAF / MEK / ERK (MAPK)93330
T-cell exhaustion103330
The angiogenic switch & tumour vessels103330
The cancer-immunity cycle83330
The pre-metastatic niche93330
Antigen presentation & immune editing92220
Base excision repair, PARP & alkylation damage102220
BCR::ABL1 (Philadelphia chromosome)82220
Cancer stem cells & phenotypic plasticity62210
Cellular senescence72220
Chromosomal instability & aneuploidy92220
Drivers, passengers & the two-hit model92220
Drug efflux pumps (ABC transporters)92220
Extrinsic apoptosis (death receptors)92220
Intravasation & circulating tumour cells102220
Lipid synthesis, uptake & cholesterol112220
Menin / KMT2A (HOXA9-MEIS1 axis)82220
NK-cell recognition: missing self & stress ligands92210
Oestrogen receptor signalling92220
SWI/SNF chromatin remodelling72200
VEGF angiogenesis72220
VHL / HIF oxygen sensing72220
Androgen receptor signalling81110
Autophagy71110
B-cell receptor / BTK signalling (to NF-κB)91110
Cancer metabolism91110
CD47 / SIRPα (the 'don't eat me' signal)71100
Clonal evolution & minimal residual disease71110
Clonal haematopoiesis (CHIP)71110
Ferroptosis & regulated cell death81110
Field cancerisation61110
Inflammation & NF-κB81110
Intrinsic apoptosis (BCL-2 family)71110
Invasion: proteases, adhesion & the invasive front101100
JAK–STAT signalling71110
Microbiome–tumour interactions81110
mRNA translation (eIF4F / mTOR)71110
Mutagenesis & mutational signatures91110
Mutant IDH / 2-hydroxyglutarate71110
MYC71100
Notch signalling61110
RNA splicing71110
The blood–brain barrier & brain metastasis91110
Basement membrane & tissue barriers90000
Cancer cachexia60000
Cancer neuroscience (nerve–tumour signalling)60000
cGAS–STING innate sensing80000
Epithelial–mesenchymal transition & drug efflux80000
Hedgehog signalling60000
Hippo–YAP/TAZ60000
KEAP1–NRF2 antioxidant pathway60000
Organ tropism: seed and soil100000
TGF-β signalling70000
The metastatic cascade90000
Tumour dormancy60000
Wnt / β-catenin70000
LegendApprovedPhase 3Phase 2Phase 1PreclinicalDruggable node, no drugNo target in corpus

Synthetic lethality: paired dependencies

Two genes are synthetically lethal when losing either alone is fine but losing both kills the cell. Cancers that have already lost one (a tumour suppressor you cannot put back) become uniquely dependent on the other, which you can drug. BRCA and PARP was the first proof; a dozen more pairs are now in trials.

NodeTargetProducts hitting the node
→ PARP1, POLQPARP
BRCA / HRD lossBRCA1 / BRCA2 (HRD)
TP53 loss, CCNE1 ampTP53
→ ATRATRDruggable node, no drug in corpus
→ PRMT5, MAT2APRMT5 (MTAP-deleted cancers)Druggable node, no drug in corpus
→ WEE1, PKMYT1, ATRWEE1Druggable node, no drug in corpus
→ WRN helicaseWRN helicase (MSI-high cancers)Druggable node, no drug in corpus
ATM lossno target in corpus
CRISPR screens (DepMap)no target in corpus
MSI-H (MMR loss)no target in corpus
MTAP deletionno target in corpus
Resistance: restore lost pathno target in corpus
Selective inhibitorno target in corpus

How drugs attack it, from the pathway page: PARP inhibitors for BRCA/HRD (approved in four cancers); MTA-cooperative PRMT5 inhibitors for MTAP-deleted tumours (mesothelioma, NSCLC, pancreatic; phase 1-2); WEE1 (azenosertib), PKMYT1 (lunresertib) and ATR (ceralasertib, camonsertib) inhibitors in TP53-mutant, CCNE1-amplified and ATM-deficient tumours; WRN inhibitors for MSI-H; SMARCA2 degraders for SMARCA4-deficient cancers.

DNA replication stress

Cancers copy their DNA too fast and with broken checkpoints, so replication forks stall and collapse. They survive only by leaning on emergency repair kinases such as ATR, CHK1, and WEE1, which is why blocking those kinases can be selectively lethal.

NodeTargetProducts hitting the node
Oncogenes (MYC, cyclin E, RAS)KRAS
TP53 (lost)TP53
ATR → CHK1ATRDruggable node, no drug in corpus
WEE1 / PKMYT1 restrain CDK1WEE1Druggable node, no drug in corpus
Excess origin firing, short G1no target in corpus
Fork collapse → DSBsno target in corpus
G2/M checkpointno target in corpus
Mitotic catastropheno target in corpus
Stalled forks, ssDNA gapsno target in corpus

How drugs attack it, from the pathway page: ATR inhibitors (ceralasertib, camonsertib) alone and with PARP inhibitors or IO; WEE1 (azenosertib) and PKMYT1 (lunresertib) inhibitors in CCNE1-amplified and TP53-mutant tumours; PARP inhibitors trap forks in HRD tumours (see DDR); Gemcitabine and other antimetabolites are classical replication-stress inducers.

p53 / RB / cell-cycle checkpoint

The p53 and RB checkpoints are the cell's brakes. p53 senses damage and stops the cell from copying itself; RB holds the cell at the G1 gate until CDK4/6 unlocks it. Cancers cut these brakes.

NodeTargetProducts hitting the node
CDK4/6 – cyclin DCDK4/6
p53TP53
ATM / ATRATRDruggable node, no drug in corpus
WEE1 (G2/M)WEE1Druggable node, no drug in corpus
DNA damageno target in corpus
E2Fno target in corpus
MDM2no target in corpus
p21no target in corpus
RBno target in corpus
S phase (DNA replication)no target in corpus

How drugs attack it, from the pathway page: CDK4/6 inhibitors (palbociclib, ribociclib, abemaciclib); WEE1 inhibitors (azenosertib) and PLK1 inhibitors in TP53-mutant tumours; MDM2 inhibitors (brigimadlin) in TP53-wild-type tumours; p53 Y220C reactivator rezatapopt; CDK2 inhibitors for CCNE1-amplified and CDK4/6-resistant disease.

The p53 network (guardian of the genome)

p53 is the cell's emergency coordinator. Damage, oncogene stress, or lack of oxygen switch it on; it then pauses division, orders repairs, or triggers suicide or permanent retirement. MDM2 keeps it switched off in healthy cells. Half of all cancers break p53 outright; many of the rest over-produce MDM2.

NodeTargetProducts hitting the node
p53TP53
PUMA, NOXA → apoptosisBCL-2
DNA damage (ATM/ATR)ATRDruggable node, no drug in corpus
MDM2 / MDMXMDM2Druggable node, no drug in corpus
Hypoxia, ribosome stressno target in corpus
Oncogene stress → ARFno target in corpus
p21 → arrestno target in corpus
Senescence, repairno target in corpus
TP53 mutation (~50%)no target in corpus

How drugs attack it, from the pathway page: MDM2 inhibitors (brigimadlin, milademetan, navtemadlin) for TP53-wild-type, MDM2-amplified tumours; Mutant p53 reactivators: rezatapopt (Y220C); eprenetapopt failed in phase 3 MDS; TP53-mutant tumours are approached via WEE1, ATR, PLK1 dependence and via p53-independent chemotherapy; TP53 status as biomarker: del17p CLL, MDS/AML risk, Li-Fraumeni surveillance.

Double-strand break repair: HR versus end joining

A break through both strands of DNA is the most dangerous lesion a cell faces. Two crews compete to fix it: homologous recombination copies the answer from the sister chromosome (accurate, needs BRCA), while end joining simply glues the ends (fast, sloppy). Which crew wins decides whether PARP inhibitors and radiation kill the cell.

NodeTargetProducts hitting the node
PALB2–BRCA2 → RAD51BRCA1 / BRCA2 (HRD)
PARP trapping → breaksPARP
Resection: BRCA1–CtIPBRCA1 / BRCA2 (HRD)
MRN → ATM → CHK2ATRDruggable node, no drug in corpus
53BP1–Shieldin (protect)no target in corpus
Accurate HR (sister copy)no target in corpus
Double-strand breakno target in corpus
Error-prone joiningno target in corpus
NHEJ: Ku, DNA-PKcs, LIG4no target in corpus
POLQ end joining (backup)no target in corpus

How drugs attack it, from the pathway page: PARP inhibitors (olaparib, niraparib, rucaparib, talazoparib) in BRCA/HRD ovarian, breast, prostate, pancreatic cancer; Platinum chemotherapy and radiation add breaks HR-deficient cells cannot fix; POLQ inhibitors (novobiocin analogues), ATR inhibitors after ATM loss, DNA-PK inhibitors with radiotherapy (trials); HRD testing (genomic scars, BRCA sequencing) and RAD51 foci assays select patients; reversion mutations detected in ctDNA flag resistance.

Nutrient competition & metabolic immunosuppression

Tumours and immune cells eat from the same plate. Cancer cells hoard glucose and glutamine, dump lactate and acid, and burn tryptophan and arginine into by-products that paralyse T cells. The tumour wins the food fight, and the immune system loses before it has fired a shot.

NodeTargetProducts hitting the node
Arginase (MDSC, TAM)CSF1R
HypoxiaHIF-2α
T-cell / NK dysfunctionPD-1
CD39 → CD73 → adenosineCD73 / adenosine axisDruggable node, no drug in corpus
Glucose, glutamine depletedno target in corpus
Glycolytic tumour cellno target in corpus
IDO1 → kynurenineno target in corpus
Lactate, acidity (MCT4)no target in corpus
M2 macrophage polarisationno target in corpus

How drugs attack it, from the pathway page: IDO1 inhibitor epacadostat failed with pembrolizumab in melanoma (ECHO-301); lesson on phase 2 mirages; Adenosine axis: CD73 antibodies (oleclumab) and A2A antagonists, modest activity so far; Arginase inhibitors and glutamine antagonists (DRP-104) designed to spare T cells; Vessel normalisation and hypoxia relief; metabolically armoured CAR-T; diet trials.

The cell-cycle engine (cyclins & CDKs)

Cell division runs on a clock made of cyclins and their kinases (CDKs), each pair firing in order: D-CDK4/6 to leave rest, E-CDK2 to start copying DNA, A-CDK2 to finish, B-CDK1 to divide. Cancers speed the clock; CDK inhibitors slow it.

NodeTargetProducts hitting the node
Cyclin D – CDK4/6CDK4/6
Mitogens (ER, RTK, RAS)Estrogen receptor (ERα)
p21 / p27TP53
WEE1 / PKMYT1WEE1Druggable node, no drug in corpus
Cyclin B – CDK1no target in corpus
Cyclin E – CDK2no target in corpus
Mitosisno target in corpus
p16 (CDKN2A)no target in corpus
RB → E2F releasedno target in corpus
S phase (cyclin A)no target in corpus

How drugs attack it, from the pathway page: CDK4/6 inhibitors (palbociclib, ribociclib, abemaciclib) in HR+ breast cancer; CDK4-selective atirmociclib to spare neutrophils; CDK2 inhibitors for CCNE1-amplified and CDK4/6-resistant disease (trials); WEE1 (azenosertib) and PKMYT1 (lunresertib) inhibitors force premature mitosis in CCNE1-amplified or TP53-mutant cells; CDK7 and CDK9 inhibitors hit transcription as well as the cycle.

Transcriptional machinery & addiction

Cancer cells run a few genes (MYC, their lineage factors, their fusion oncogenes) at extreme volume from giant control regions called super-enhancers. The amplifiers, BRD4, CDK7, CDK9 and Mediator, are the same in every cell, but cancers are unusually dependent on them, and that dependence is druggable.

NodeTargetProducts hitting the node
Lineage TFs (ER, AR, ASCL1)Androgen receptor
Menin–KMT2A (AML)Menin
MYC, MCL-1 (short-lived)BCL-2
Fusion TFs (EWSR1-FLI1)EWSR1-FLI1 fusionDruggable node, no drug in corpus
BRD4, Mediator, p300no target in corpus
CDK7 (TFIIH) initiationno target in corpus
CDK9 (P-TEFb) elongationno target in corpus
RNA Pol IIno target in corpus
Super-enhancerno target in corpus

How drugs attack it, from the pathway page: Nuclear receptor drugs (endocrine therapy, ARPIs, SERDs, PROTAC vepdegestrant) are transcription drugs; Menin inhibitors revumenib and ziftomenib in KMT2A-rearranged and NPM1-mutant AML; BET inhibitors and BET/CBP degraders; CDK7 (samuraciclib) and CDK9 inhibitors in trials; Fusion-TF cancers (Ewing, NUT carcinoma) are the proving ground for transcriptional drugs.

DNA damage response & homologous recombination

The DNA damage response is the cell's set of repair crews. Single-strand breaks are patched by PARP; double-strand breaks by BRCA-dependent homologous recombination. Lose one crew and the cell survives; lose both and it dies. That is how PARP inhibitors work.

NodeTargetProducts hitting the node
BRCA1/2 – RAD51 (HR)BRCA1 / BRCA2 (HRD)
PARP1PARP
ATR / CHK1ATRDruggable node, no drug in corpus
Accurate repairno target in corpus
Double-strand breakno target in corpus
Genomic collapse / deathno target in corpus
NHEJ / POLQ (error-prone)no target in corpus
Replication fork collapseno target in corpus
Single-strand breakno target in corpus

How drugs attack it, from the pathway page: PARP inhibitors in BRCA/HRD ovarian, breast, prostate, pancreatic cancer; Platinum chemotherapy (crosslinks) in HRD tumours; ATR inhibitors (ceralasertib) in ATM-deficient or PARP-resistant tumours; POLQ inhibitors (novobiocin analogues) in HRD; PARP1-selective saruparib to widen therapeutic window.

Ubiquitin–proteasome system & protein homeostasis

Cells tag unwanted proteins with a small marker called ubiquitin and feed them into a shredder, the proteasome. Myeloma cells, which make antibody in bulk, die if the shredder jams; and the newest drugs hijack the tagging machinery to make a cancer destroy its own oncoproteins.

NodeTargetProducts hitting the node
Glues / PROTACs hijack E3Estrogen receptor (ERα)
Substrate (IKZF1/3, p53, HIF)HIF-2α
E3 ligase (CRBN, VHL, MDM2)MDM2Druggable node, no drug in corpus
26S proteasome (β5)no target in corpus
Degradationno target in corpus
DUBs (USP7)no target in corpus
E1 → E2 ubiquitinno target in corpus
HSP90 chaperonesno target in corpus
K48 ubiquitin chainno target in corpus
UPR, IκB → NF-κBno target in corpus

How drugs attack it, from the pathway page: Proteasome inhibitors bortezomib, carfilzomib, ixazomib in multiple myeloma and mantle cell lymphoma; Cereblon glues: lenalidomide, pomalidomide; CELMoDs iberdomide, mezigdomide, golcadomide; PROTACs: vepdegestrant (ER), BGB-16673 (BTK), AR degraders; degrader-antibody conjugates deliver them by antibody; Reactivating degradation of oncoproteins (MDM2 inhibition for p53) and blocking DUBs are in trials.

Mismatch repair & microsatellite instability

After DNA is copied, a proofreading crew fixes the letters the polymerase got wrong. Lose it and the genome fills with thousands of small errors, especially in repetitive stretches (microsatellites). Those errors make abnormal proteins that the immune system can see, which is why immunotherapy works so well in these cancers.

NodeTargetProducts hitting the node
Checkpoint-inhibitor responsePD-1
WRN dependenceWRN helicase (MSI-high cancers)Druggable node, no drug in corpus
Corrected DNAno target in corpus
EXO1, Pol δ resynthesisno target in corpus
Frameshift neoantigensno target in corpus
MMR loss (Lynch, MLH1 methylation)no target in corpus
MSI-H, hypermutationno target in corpus
MutLα (MLH1–PMS2)no target in corpus
MutSα (MSH2–MSH6)no target in corpus
Replication mismatchno target in corpus

How drugs attack it, from the pathway page: Tumour-agnostic pembrolizumab and dostarlimab for MSI-H/dMMR; nivolumab ± ipilimumab in colorectal cancer; Organ-sparing: dostarlimab alone cures most dMMR rectal cancers; neoadjuvant nivolumab-ipilimumab in dMMR colon cancer; Universal MMR/MSI testing of colorectal and endometrial cancer finds Lynch syndrome; colonoscopic surveillance and aspirin for carriers; WRN helicase inhibitors as synthetic-lethal therapy for MSI-H tumours (trials).

Circadian control

Cells run on a 24-hour clock that gates cell division, DNA repair, and drug metabolism. Cancers often break their clocks, and the time of day a drug or immunotherapy is given can change how well it works.

NodeTargetProducts hitting the node
Cell-cycle gating (WEE1, MYC)WEE1Druggable node, no drug in corpus
CLOCK/BMAL1no target in corpus
DNA repair timingno target in corpus
PER/CRY (repress)no target in corpus
T-cell trafficking rhythmno target in corpus
Time-of-day drug responseno target in corpus

How drugs attack it, from the pathway page: Morning versus afternoon immunotherapy dosing (prospective trials ongoing); Chronomodulated chemotherapy infusion; Clock-modulating compounds (preclinical).

Telomere maintenance & replicative immortality

Normal cells can divide only so many times because the protective caps on their chromosomes, telomeres, wear down. Cancers switch the cap-rebuilding enzyme telomerase back on, or find another way (ALT), so they can divide forever.

NodeTargetProducts hitting the node
ATR dependence (ALT)ATRDruggable node, no drug in corpus
ALT (ATRX/DAXX loss)no target in corpus
Each division shortens telomeresno target in corpus
Replicative immortalityno target in corpus
Senescence / crisisno target in corpus
TERT reactivation (promoter mutation)no target in corpus

How drugs attack it, from the pathway page: Imetelstat (telomerase inhibitor) approved in MDS (2024); solid-tumour use unproven; ATR inhibitors in ALT-positive tumours; TERT promoter mutation as a urine/plasma biomarker (bladder, glioma).

Cold tumours: immune deserts and exclusion

Tumours come in three immune weathers: inflamed (T cells inside, checkpoint drugs work), excluded (T cells stuck at the edge), and desert (no T cells at all). Most common cancers are excluded or desert, and turning them 'hot' is the central problem of immunotherapy.

NodeTargetProducts hitting the node
Abnormal vessels (VEGF)VEGF / VEGFR
Inflamed → PD-1 responsePD-1
Myeloid barrierCSF1R
β-catenin, PTEN loss → no cDC1PIK3CA / PI3K-alpha
CXCL9/10 silenced (EZH2)EZH2
TGF-β CAFs, collagenFAP
Immune desertno target in corpus
Immune exclusionno target in corpus
Low TMB, MHC lossno target in corpus
RT, STING, viruses, vaccinesno target in corpus

How drugs attack it, from the pathway page: Radiotherapy, immunogenic chemotherapy and TOP1 ADCs to seed antigen and STING signalling; oncolytic viruses (T-VEC, RP1) and in situ vaccination; Anti-VEGF and PD-1×VEGF bispecifics open the vessel gate; FAP-, CXCR4- and TGF-β-directed agents (mostly modest so far); Epigenetic priming (EZH2, DNMT inhibitors) to restore chemokines; STING agonists intratumourally; Bypass the weather: T-cell engagers, CAR-T, TCR-T and vaccines that bring or make their own T cells.

Resistance routes: how a blocked pathway comes back

When a drug blocks a cancer's engine, the cancer has five ways back: change the part the drug binds, make more of it, take a side road, switch to a different engine altogether, or stop letting the drug in. Knowing which route a tumour took decides the next drug.

How drugs attack it, from the pathway page: Next-generation inhibitors for on-target mutations (osimertinib for T790M, lorlatinib for ALK G1202R, pirtobrutinib for BTK C481S, asciminib for T315I); Vertical and parallel combinations: BRAF+MEK, KRAS G12C + EGFR in CRC, CDK4/6 + endocrine + PI3K/AKT; Switching modality on progression: ADCs, radioligands, engagers and CAR-T are not cross-resistant with small molecules; Serial ctDNA to detect the route (C797S, MET amp, ESR1) and adaptive dosing; see the resistance atlas for every class.

Lineage plasticity & neuroendocrine transformation

Under pressure from a drug that blocks its identity (the androgen receptor in prostate cancer, EGFR in lung cancer), a tumour can change what kind of cell it is, becoming a small-cell neuroendocrine cancer that no longer needs the blocked signal. It is the ultimate escape: not a new mutation in the engine, but a new engine.

NodeTargetProducts hitting the node
Adenocarcinoma (AR / EGFR)Androgen receptor
ARPI or EGFR TKI pressureEGFR
DLL3, B7-H3, SEZ6 surfaceDLL3
TP53 + RB1 lossTP53
SOX2, EZH2, ASCL1/NEUROD1EZH2
AR / EGFR indifferentno target in corpus
EZH2 inhibitors block switchno target in corpus
Neuroendocrine / small-cellno target in corpus
Tarlatamab, platinum-etoposideno target in corpus

How drugs attack it, from the pathway page: Re-biopsy at progression when the clinical picture and markers diverge; ctDNA TP53/RB1 loss as a warning; DLL3 T-cell engager tarlatamab (SCLC; trials in neuroendocrine prostate cancer); B7-H3 and SEZ6 ADCs; EZH2 inhibitors (mevrometostat with enzalutamide, tazemetostat) to prevent or reverse plasticity; Aurora A inhibitors for MYCN/ASCL1-high states; Platinum-etoposide gives transient responses in transformed disease.

Receptor tyrosine kinase activation

Growth-factor receptors are antennas on the cell surface that pair up when a signal lands and switch on the growth relays inside. Cancers mutate, multiply, or fuse these antennas so they broadcast 'grow' with no signal at all. Most targeted drugs, antibodies and ADCs start here.

How drugs attack it, from the pathway page: TKIs by driver: osimertinib (EGFR), lorlatinib/alectinib (ALK), selpercatinib (RET), larotrectinib/entrectinib (NTRK), capmatinib/tepotinib (MET), imatinib (KIT/PDGFRA/BCR-ABL), zongertinib (HER2); Antibodies: trastuzumab/pertuzumab (HER2), cetuximab/panitumumab (EGFR); bispecifics amivantamab (EGFR×MET), zanidatamab, zenocutuzumab (HER2×HER3); ADCs use the receptor as an address: T-DXd, T-DM1, patritumab deruxtecan (HER3), telisotuzumab vedotin (MET); Combining with MET or downstream inhibitors closes bypass routes.

Tumour microenvironment (TME)

A tumour is not just cancer cells. It is a neighbourhood of fibroblasts, immune cells, blood vessels, nerves, and scaffolding that the cancer recruits and corrupts, and that decides whether drugs and immune cells can get in.

How drugs attack it, from the pathway page: Checkpoint blockade (PD-1, CTLA-4, LAG-3) releases exhausted T cells; Anti-VEGF normalises vessels and improves infiltration; FAP-targeted imaging and radioligands attack CAFs; CSF1R, CD47/SIRPα, CXCR4, TGF-β, adenosine (A2A/CD73) agents target myeloid and stromal suppression; most have been modest so far; Radiation and oncolytic viruses convert excluded tumours.

Fibroblast activation, desmoplasia & matrix stiffness

Tumours recruit the body's repair cells, fibroblasts, and keep them in wound-healing mode forever. The scar tissue they lay down (desmoplasia) squeezes blood vessels shut, walls out immune cells, stiffens the tissue in a way that itself tells cancer cells to grow, and is why pancreatic cancer is so hard to treat.

NodeTargetProducts hitting the node
Hedgehog (SMO) paradoxSmoothened (hedgehog pathway)
iCAF (IL-6, CXCL12, LIF)JAK2
T-cell exclusionPD-1
myCAF (FAP, αSMA, collagen)FAP
Collagen, HA, LOX crosslinksno target in corpus
Fibroblast / stellate cellno target in corpus
Growth, EMT, chemoresistanceno target in corpus
Pressure: vessels collapseno target in corpus
Stiffness → FAK → YAP/TAZno target in corpus
Tumour: TGF-β, PDGF, Hh, IL-1no target in corpus

How drugs attack it, from the pathway page: FAP-targeted imaging (FAPI PET) and radioligands (FAP-2286) and FAP/LRRC15 CAR-T; Reprogramming: vitamin D analogues, losartan with chemoradiation (PDAC trials), IL-1/JAK inhibition for iCAFs; FAK inhibitors soften stroma and improve immunotherapy entry (trials); mechanobiology approaches; Vismodegib and PEGPH20 failed in PDAC: stromal depletion can accelerate disease.

Glutamine addiction

After glucose, glutamine is the tumour's favourite food. It feeds the energy cycle, donates nitrogen for making DNA letters, and makes the antioxidant glutathione. MYC- and KRAS-driven cancers eat so much of it that they starve the T cells next door.

NodeTargetProducts hitting the node
IDH → 2-HG / reductiveIDH1 / IDH2
mTORC1 sensingAKT
MYC, KRAS drive uptakeKRAS
T cells starvedPD-1
Glutamateno target in corpus
Glutaminase (GLS)no target in corpus
Glutamine (SLC1A5)no target in corpus
Glutathione, NADPHno target in corpus
Nucleotides (N donor)no target in corpus
α-KG → TCA anaplerosisno target in corpus

How drugs attack it, from the pathway page: Asparaginase (depletes asparagine and glutamine) in ALL; Glutaminase inhibitor telaglenastat: negative in RCC and NSCLC; glutamine antagonist DRP-104 and ASCT2 blockers in early trials; IDH inhibitors (ivosidenib, vorasidenib) block the oncometabolite branch; Glutamine PET (18F-FGln) for glioma; metabolic imaging to pick fuel-dependent tumours.

Myeloid suppression: TAMs, MDSCs & don't-eat-me signals

Tumours recruit the body's clean-up cells (macrophages and immature myeloid cells) and re-train them as bodyguards. They switch off T cells, build vessels, and, when a therapeutic antibody flags a cancer cell for eating, are told 'don't eat me' by CD47 on its surface.

NodeTargetProducts hitting the node
CSF1, CCL2, G-CSF, VEGFVEGF / VEGFR
IL-10, TGF-β, PD-L1PD-L1
TAMs (CSF1R, TREM2)CSF1R
CD47 → SIRPα 'don't eat'CD47
Angiogenesis, metastasisno target in corpus
CD40 agonists, TLRs reprogramno target in corpus
MDSCs (arginase, ROS)no target in corpus
Monocytes, neutrophilsno target in corpus
Phagocytosis (ADCP)no target in corpus
T cells suppressedno target in corpus

How drugs attack it, from the pathway page: CSF1R inhibitors pexidartinib and vimseltinib (approved in tenosynovial giant cell tumour; disappointing in cancer); CD47/SIRPα: magrolimab failed in AML/MDS; next-generation bispecifics and SIRPα-Fc in trials; CD40 agonists, TLR7/9 agonists, CXCR2/CCR2 blockade, PI3Kγ inhibitors as reprogrammers; CAR-macrophages, trained innate immunity (BCG) and antibody engineering for ADCP.

PD-1 / PD-L1 immune checkpoint & T-cell activation

How T cells decide to attack. A T cell needs to see the target (TCR-MHC) and get a 'go' signal (CD28). PD-1 and CTLA-4 are 'stop' signals; tumours exploit them. Checkpoint inhibitors remove the stop.

NodeTargetProducts hitting the node
CTLA-4 (stop)CTLA-4
LAG-3 / TIGITLAG-3
PD-1 on T cellPD-1
PD-L1 on tumourPD-L1
Activated CD8 T cellno target in corpus
CD28 – B7 (go)no target in corpus
Dendritic cell (antigen + B7)no target in corpus
IFN-γno target in corpus
TCR – peptide/MHCno target in corpus
Tumour cell killingno target in corpus

How drugs attack it, from the pathway page: Anti-PD-1 (pembrolizumab, nivolumab), anti-PD-L1 (atezolizumab, durvalumab); Anti-CTLA-4 (ipilimumab) ± anti-PD-1; Anti-LAG-3 (relatlimab) + nivolumab; PD-1×VEGF bispecifics (ivonescimab); Vaccines, T-cell engagers, and CAR-T supply signal 1 by other means.

Complement in cancer

Complement is a cascade of blood proteins that punches holes in things marked by antibodies and calls in inflammatory cells. Therapeutic antibodies such as rituximab use it to kill cancer cells; tumours defend themselves with shields (CD46, CD55, CD59), and the cascade's own by-products (C5a) can recruit the myeloid cells that protect the tumour.

NodeTargetProducts hitting the node
C5a → MDSC, neutrophilsCSF1R
CD8 T cells suppressedPD-1
IgG1 antibody (rituximab)CD20
ADCC (NK, CD16)no target in corpus
Alternative / lectinno target in corpus
C1q classical routeno target in corpus
C3 convertase → C3bno target in corpus
C5 → C5a + MAC (C5b-9)no target in corpus
CD46, CD55, CD59 shieldsno target in corpus
CDC lysis, opsonisationno target in corpus

How drugs attack it, from the pathway page: CD20 and CD38 antibodies (rituximab, obinutuzumab, daratumumab, isatuximab) kill partly through complement; Fc engineering tunes CDC versus ADCC; Blocking complement regulators (CD55/CD59) to restore CDC (preclinical); C5aR1 antagonists with checkpoint inhibitors to remove myeloid recruitment (early trials); Complement inhibition to manage infusion reactions and CAR-T inflammation.

DNA replication & origin licensing

Before a cell divides it must copy three billion letters of DNA exactly once. It does this by 'licensing' thousands of start points in advance and then firing them in waves. Cancers fire too many too fast, and many chemotherapies work by starving or jamming the copying machinery.

NodeTargetProducts hitting the node
CDK2 / DDK firingCDK4/6
MYC, cyclin E: excess originsKRAS
TOP1 (chemo, ADC payloads)TROP2
CMG helicase + Pol ε/δno target in corpus
dNTP supply (RNR)no target in corpus
Geminin, CRL4-CDT2no target in corpus
MCM2-7 loaded (licence)no target in corpus
ORC, CDC6, CDT1no target in corpus
Replication forkno target in corpus
Replication stressno target in corpus

How drugs attack it, from the pathway page: Antimetabolites (5-FU, gemcitabine, methotrexate, pemetrexed, hydroxyurea, cytarabine) starve or terminate synthesis; Topoisomerase I poisons (irinotecan, topotecan) and their ADC payloads (SN-38, DXd, exatecan) trap the enzyme ahead of forks; Platinum crosslinks and alkylators block polymerases; ATR, CHK1, WEE1 inhibitors exploit the stress cancers create (see replication stress); CDC7 and POLQ inhibitors in trials.

Drug-tolerant persister cells

Even when a drug wipes out 99% of a tumour, a few cells survive without any resistance mutation: they go quiet, stop dividing, and wait. These persisters are the seed of relapse. They are hard to kill precisely because they are not doing much, but they have their own weaknesses.

NodeTargetProducts hitting the node
Efflux, autophagy, BCL-XLBCL-2
Targeted drug or chemoEGFR
KDM5A, H3K27me3, YAP, NF-κBEZH2
APOBEC → resistance mutationno target in corpus
Bulk tumour diesno target in corpus
FAO, low GSH → GPX4 dependenceno target in corpus
Ferroptosis inducersno target in corpus
Persister: slow-cycling, reversibleno target in corpus
Relapse (MRD → clinical)no target in corpus
Upfront combinations, holidaysno target in corpus

How drugs attack it, from the pathway page: Upfront combinations that pre-empt persisters: osimertinib + chemotherapy (FLAURA2), amivantamab + lazertinib (MARIPOSA), BRAF + MEK + anti-PD-1; GPX4 and ferroptosis inducers, BCL-XL/MCL-1 inhibitors, KDM5 and EZH2 inhibitors (preclinical to phase 1); MRD-guided treatment: ctDNA clearance to de-escalate, persistence to intensify or switch; Intermittent or adaptive dosing to delay commitment to resistance (trials in melanoma and prostate cancer).

Epigenetic reprogramming

Cancer changes not just its genes but how they are read: chemical tags on DNA and histones silence guardians and awaken growth programmes. Unlike mutations, these changes are reversible, which is the hope behind epigenetic drugs.

NodeTargetProducts hitting the node
DNA methylation (DNMT, TET2, IDH/2-HG)IDH1 / IDH2
Menin–KMT2A scaffoldMenin
Histone marks (EZH2, KMT2A, H3K27M)EZH2
Active oncogenic programmes, persister statesno target in corpus
Chromatin stateno target in corpus
Readers (BET) & remodellers (SWI/SNF)no target in corpus
Silenced tumour suppressors, antigensno target in corpus

How drugs attack it, from the pathway page: Hypomethylating agents (azacitidine, decitabine) with venetoclax in AML; Menin inhibitors (revumenib, ziftomenib) in KMT2A/NPM1 leukaemia; IDH inhibitors reverse 2-HG hypermethylation; HDAC, BET, LSD1 inhibitors mostly in trials; epigenetic priming for immunotherapy.

FGF / FGFR signalling

Fibroblast growth factor receptors are growth antennas on the cell surface. Bladder cancer mutates FGFR3, bile duct cancer fuses FGFR2 to other genes, and stomach cancer overproduces FGFR2b; each has its own drug, and each brings a tell-tale side effect (high phosphate) because the same receptors control phosphate in the kidney.

NodeTargetProducts hitting the node
FGFR1-4 (FGFR2 fusions, FGFR3 mutations)FGFR2
GAB1 → PI3K → AKTPIK3CA / PI3K-alpha
GRB2 / SOS → RAS → MAPKKRAS
FGF ligands (+ heparan sulphate / Klotho)no target in corpus
FGF23 → FGFR1 (kidney phosphate; drug side effect)no target in corpus
FRS2no target in corpus
PLCγ / STATno target in corpus
Proliferation, survival, angiogenesisno target in corpus

How drugs attack it, from the pathway page: Erdafitinib for FGFR3-altered advanced urothelial cancer after platinum and PD-1/PD-L1 therapy (THOR); Pemigatinib and futibatinib for FGFR2-fusion cholangiocarcinoma; futibatinib's covalent binding keeps activity against gatekeeper mutations; Bemarituzumab (anti-FGFR2b) with chemotherapy in FGFR2b-overexpressing gastric cancer (FORTITUDE-101); Phosphate binders and diet for hyperphosphataemia; eye examinations for central serous retinopathy; Selective FGFR2 and FGFR3 inhibitors under development to widen the therapeutic window.

Mitosis & the spindle assembly checkpoint

When a cell divides, a scaffold of microtubules (the spindle) pulls one copy of each chromosome to each side. A checkpoint holds the split until every chromosome is hooked on. Taxanes and vinca alkaloids freeze the spindle so the cell is stuck at this checkpoint until it dies.

NodeTargetProducts hitting the node
Mitotic death (BCL-XL↓)BCL-2
p53 arrestTP53
Taxanes, vincas, MMAE, DM1HER2
Anaphase (separase)no target in corpus
APC/C–CDC20no target in corpus
Centrosomes (Aurora A, PLK1)no target in corpus
Kinetochore attachmentno target in corpus
SAC: MAD2, BUBR1, MPS1no target in corpus
Slippage → tetraploidno target in corpus
Spindle microtubulesno target in corpus

How drugs attack it, from the pathway page: Taxanes (paclitaxel, docetaxel, cabazitaxel), eribulin, vinca alkaloids (vincristine, vinblastine, vinorelbine); Tubulin-payload ADCs: MMAE (enfortumab, brentuximab, polatuzumab vedotin), DM1 (T-DM1), DM4 (mirvetuximab); Aurora A (alisertib), PLK1 and MPS1 inhibitors; KIF18A inhibitors for CIN-high tumours (trials); BCL-XL degraders to tip arrested cells into death.

Oncogenic viruses

About one cancer in eight worldwide is caused by a virus. HPV, hepatitis B and C, Epstein-Barr, HTLV-1, KSHV and Merkel cell polyomavirus each hijack the same brakes cancer normally has to mutate, which is why vaccines against HPV and HBV are among the most effective anti-cancer drugs ever made.

NodeTargetProducts hitting the node
p53 degradedTP53
RB inactivatedCDK4/6
Viral antigens → IO responsePD-1
Chronic inflammation, cirrhosisno target in corpus
EBV LMP1, EBNAno target in corpus
HBV / HCVno target in corpus
HPV E6 / E7no target in corpus
NF-κB, immortalisationno target in corpus
Vaccination, antiviralsno target in corpus
Virus-driven cancerno target in corpus

How drugs attack it, from the pathway page: HPV vaccination (Gardasil 9) and HBV vaccination prevent the infection; HCV direct-acting antivirals and H. pylori eradication remove the driver; HPV testing and colposcopy find and excise precursor lesions; Checkpoint inhibitors work well in Merkel cell (avelumab, retifanlimab) and HPV+ cancers; EBV- and HPV-specific TCR-T and vaccines are in trials; Plasma EBV DNA screens for nasopharyngeal carcinoma and tracks response.

PI3K / AKT / mTOR

The cell's 'grow and survive' circuit. Growth signals from the surface switch on PI3K, which switches on AKT, which switches on mTOR, which builds proteins and blocks self-destruction.

NodeTargetProducts hitting the node
AKTAKT
PI3K (PIK3CA)PIK3CA / PI3K-alpha
RTK (HER2, EGFR)HER2
FOXO / BAD (apoptosis)no target in corpus
mTORC1no target in corpus
PIP3no target in corpus
Protein synthesis, growthno target in corpus
PTENno target in corpus
TSC1/2no target in corpus

How drugs attack it, from the pathway page: PI3Kα inhibitors (alpelisib, inavolisib) for PIK3CA-mutant HR+ breast cancer; AKT inhibitor capivasertib for PIK3CA/AKT1/PTEN-altered breast and PTEN-deficient prostate cancer; mTOR inhibitor everolimus; Dual PI3K/mTOR gedatolisib (2026); Upstream: anti-HER2, anti-EGFR.

RAS / RAF / MEK / ERK (MAPK)

The RAS-MAPK pathway is the cell's 'divide' relay. A signal at the surface flips RAS on, which passes to RAF, MEK, and ERK, which tell the nucleus to make the cell divide. KRAS and BRAF mutations jam it in the on position.

NodeTargetProducts hitting the node
RAF (BRAF)BRAF
RAS (KRAS)KRAS
RTK (EGFR, ALK, RET, MET)EGFR
Cyclin D1, MYC → proliferationno target in corpus
DUSP / SPRY feedbackno target in corpus
ERK1/2no target in corpus
GRB2 / SOS1no target in corpus
MEK1/2no target in corpus
NF1 (GAP)no target in corpus

How drugs attack it, from the pathway page: KRAS G12C inhibitors (sotorasib, adagrasib) ± anti-EGFR in colorectal cancer; Pan-RAS(ON) inhibitor daraxonrasib (phase 3, pancreatic); BRAF + MEK inhibitors (dabrafenib/trametinib, encorafenib/binimetinib); Encorafenib + cetuximab (+ chemo) in BRAF V600E CRC; Upstream: EGFR, ALK, RET, MET, NTRK inhibitors and bispecifics.

T-cell exhaustion

T cells that see their target for weeks on end without winning gradually shut down: they raise a set of brakes (PD-1, LAG-3, TIM-3, TIGIT), lose their ability to kill, and eventually lock this state into their DNA. Checkpoint drugs rescue the ones that are only partly exhausted; the terminally exhausted are beyond reach.

NodeTargetProducts hitting the node
CAR-T exhaustionCD19
Checkpoint blockadeLAG-3
PD-1, LAG-3, TIM-3, TIGITPD-1
Chronic antigen, no helpno target in corpus
Cytokines, killingno target in corpus
DNMT3A epigenetic scarno target in corpus
TCF1+ progenitor (stem-like)no target in corpus
Terminally exhaustedno target in corpus
TOX, NR4A, NFATno target in corpus
Transitory effectorno target in corpus

How drugs attack it, from the pathway page: Anti-PD-1/PD-L1; combinations with anti-LAG-3 (relatlimab-nivolumab, fianlimab) and anti-TIGIT (tiragolumab, mixed results); Earlier use (neoadjuvant) when the TCF1+ reservoir is larger; IL-2 variants and IL-15 superagonists to expand progenitors; CAR-T engineering: c-Jun overexpression, TET2/DNMT3A editing, transient rest, PD-1 knockout; Epigenetic drugs to reverse scarring (preclinical).

The angiogenic switch & tumour vessels

A tumour cannot grow beyond a couple of millimetres without its own blood supply. The 'switch' flips when the signals calling for new vessels (VEGF, FGF, angiopoietin) outweigh the ones holding them back (thrombospondin). The vessels that result are leaky and chaotic, which starves the tumour of oxygen, blocks drugs, and gives cancer cells a way out.

NodeTargetProducts hitting the node
Hypoxia (HIF), RAS, p53 lossHIF-2α
TAMs, MDSCs (bypass)CSF1R
VEGF, FGF2, ANG2, PDGFVEGF / VEGFR
Angiogenic switchno target in corpus
Hypoxia, poor delivery, exitno target in corpus
Leaky, chaotic vesselsno target in corpus
Pericytes (PDGFRβ)no target in corpus
Tip / stalk sprouting (VEGFR2)no target in corpus
TSP-1, endostatinno target in corpus
Vessel co-optionno target in corpus

How drugs attack it, from the pathway page: Anti-VEGF antibodies (bevacizumab, ramucirumab) and VEGFR TKIs (axitinib, cabozantinib, lenvatinib, sunitinib, pazopanib, tivozanib, fruquintinib, regorafenib, sorafenib); Vascular normalisation windows for IO-VEGF combinations in RCC, HCC, endometrial cancer; PD-1×VEGF bispecific ivonescimab; HIF-2α inhibition upstream (belzutifan); multikinase inhibitors hit FGFR/PDGFR escape ligands; Vessel co-option limits anti-angiogenics in liver and brain metastases.

The cancer-immunity cycle

Seven steps the immune system must complete to kill a tumour: release of antigens, pick-up by dendritic cells, priming of T cells in lymph nodes, travel, entry into the tumour, recognition, and killing. Every immunotherapy pushes on one step; every escape blocks one.

NodeTargetProducts hitting the node
3 Priming (CD28 / CTLA-4)CTLA-4
5 InfiltrationVEGF / VEGFR
7 Killing (PD-1 brake)PD-1
1 Antigen releaseno target in corpus
2 DC capture (cDC1)no target in corpus
4 Trafficking (CXCL9/10)no target in corpus
6 Recognition (MHC-I)no target in corpus
Escape at any stepno target in corpus

How drugs attack it, from the pathway page: Radiation, chemotherapy, oncolytic viruses and ADC payloads feed step 1 (immunogenic cell death); Vaccines and STING agonists load step 2; anti-CTLA-4 acts at step 3; Anti-VEGF and stromal agents open steps 4-5; Engagers, CAR-T and TCR-T replace step 6; anti-PD-1/PD-L1 releases step 7.

The pre-metastatic niche

Before a single cancer cell arrives, the primary tumour sends parcels ahead: tiny vesicles (exosomes) and hormones that recruit bone-marrow cells to a distant organ and remodel it into fertile soil. By the time the seed lands, the bed is already made.

NodeTargetProducts hitting the node
MDSCs, immune suppressionCSF1R
Primary tumour (hypoxic)HIF-2α
VEGF, G-CSF, LOX, S100A8/9VEGF / VEGFR
Arriving CTCsno target in corpus
Bone-marrow cells (VEGFR1+)no target in corpus
Colonisationno target in corpus
Exosomes (integrins, MIF)no target in corpus
Niche: fibronectin, MMP9, leakyno target in corpus
Resident cells: Kupffer, fibroblastsno target in corpus

How drugs attack it, from the pathway page: Adjuvant systemic therapy and ctDNA-guided escalation act during niche formation and early seeding; Exosome and integrin profiling to predict organ of relapse (research); exosome-based therapeutics in early development; LOX, CXCR2 and CCR2 inhibitors, and G-CSF neutralisation in models; Anti-VEGF has not prevented metastasis in adjuvant trials (bevacizumab in colon and breast), a cautionary result.

Antigen presentation & immune editing

How the immune system sees cancer, and how cancer learns to hide. Tumours display fragments of their proteins on MHC molecules; T cells kill the ones they recognise; the survivors are the ones that stopped showing fragments or switched on brakes.

NodeTargetProducts hitting the node
CD8 T cell (TCR)CD3
PD-L1 inductionPD-L1
Dendritic cell cross-presentationno target in corpus
Escape: B2M/HLA loss, JAK mutationno target in corpus
IFN-γ → JAK1/2 → STAT1no target in corpus
MHC-I / B2M loadingno target in corpus
Peptide–MHC on surfaceno target in corpus
Proteasome → peptidesno target in corpus
TAP transportno target in corpus

How drugs attack it, from the pathway page: Checkpoint inhibitors; personalised neoantigen vaccines (intismeran) supply antigen; T-cell engagers and CAR-T bypass MHC entirely; TCR-T and ImmTACs (tebentafusp) target intracellular antigens via peptide–HLA; Epigenetic drugs and interferon can re-express MHC; MHC-independent NK-cell therapies address MHC-loss escape.

Base excision repair, PARP & alkylation damage

Tens of thousands of times a day a single DNA letter is oxidised or chemically scarred. A small crew snips it out and PARP marks the nick so it gets sealed. PARP inhibitors do not just switch PARP off; they trap it on the DNA, turning a harmless nick into a lethal break when the cell copies its DNA.

NodeTargetProducts hitting the node
HR (BRCA) rescueBRCA1 / BRCA2 (HRD)
PARP1 → XRCC1PARP
Fork collapse → DSBno target in corpus
Glycosylase → APE1no target in corpus
MGMT direct reversalno target in corpus
Oxidised / alkylated baseno target in corpus
PARP trapped on DNAno target in corpus
Pol β, LIG3 sealno target in corpus
Single-strand breakno target in corpus
Temozolomide, radiationno target in corpus

How drugs attack it, from the pathway page: PARP inhibitors: talazoparib (strongest trapper), olaparib, niraparib, rucaparib; PARP1-selective saruparib; Temozolomide in MGMT-methylated glioblastoma; lomustine, dacarbazine as alkylators; PARP inhibitor + radiotherapy or + TMZ combinations, limited by marrow toxicity; PARP-radioligand combinations in trials; PARP PET imaging to quantify target.

BCR::ABL1 (Philadelphia chromosome)

Chronic myeloid leukaemia is caused by one broken gene: two chromosomes swap pieces and glue a kinase (ABL1) to a protein that forces it permanently on. Imatinib, the first drug to target it, turned a fatal disease into a manageable one, and later drugs cover the mutations that escape it.

NodeTargetProducts hitting the node
PI3K → AKTPIK3CA / PI3K-alpha
RAS → MAPKKRAS
BCR::ABL1 kinase (p210 / p190)no target in corpus
GRB2 / GAB2no target in corpus
Proliferation, survival, genomic instability → CML, Ph+ ALLno target in corpus
Reactive oxygen species → new mutationsno target in corpus
STAT5no target in corpus
t(9;22) translocationno target in corpus

How drugs attack it, from the pathway page: Imatinib, the first-generation ATP-site inhibitor; dasatinib, nilotinib, bosutinib as more potent second-generation options; Ponatinib for the T315I gatekeeper mutation; Asciminib, an allosteric STAMP inhibitor, alone or with an ATP-site inhibitor against compound mutations; Molecular monitoring (BCR::ABL1 transcripts) to guide treatment-free remission attempts; In Ph-positive ALL: TKI with chemotherapy or with blinatumomab, and transplant for high-risk disease.

Cancer stem cells & phenotypic plasticity

Some cancer cells behave like stem cells: they can regrow the whole tumour, resist treatment, and switch identities. This plasticity explains why tumours come back and why some lung and prostate cancers transform into a different cancer type under therapy.

NodeTargetProducts hitting the node
Lineage switch (NE transformation)DLL3
EZH2, SWI/SNF, TP53/RB1 lossEZH2
Differentiated bulkno target in corpus
Mesenchymal / drug-tolerant persisterno target in corpus
Stem-like stateno target in corpus
Wnt / Notch / Hedgehog nicheno target in corpus

How drugs attack it, from the pathway page: Differentiation therapy: ATRA/arsenic in APL (curative), menin inhibitors differentiate KMT2A/NPM1 leukaemias; EZH2, LSD1, and BET inhibitors to block plasticity (trials); DLL3-directed tarlatamab for neuroendocrine-transformed tumours; MRD-directed therapy to catch persisters before regrowth.

Cellular senescence

Damaged cells can stop dividing permanently instead of dying. That protects against cancer at first, but senescent cells linger, secrete inflammatory signals, and after chemotherapy can help tumours relapse, so removing them (senolytics) is a new strategy.

NodeTargetProducts hitting the node
p16 → RBCDK4/6
p53 → p21TP53
Inflammation, relapse, resistanceno target in corpus
Oncogene / therapy stressno target in corpus
SASP (IL-6, IL-8, MMPs)no target in corpus
Senolytics (BCL-XL, uPAR CAR-T)no target in corpus
Stable arrestno target in corpus

How drugs attack it, from the pathway page: Senescence-inducing therapy (CDK4/6 inhibitors, chemotherapy, radiation) followed by senolytics (one-two punch); Navitoclax and BCL-XL PROTACs; uPAR-targeted CAR-T (preclinical); SASP modulation with JAK inhibitors or IL-6 blockade.

Chromosomal instability & aneuploidy

Most cancers have the wrong number of chromosomes and keep shuffling them at every division. This chaos fuels evolution and drug resistance, but it also stresses the cell and can trigger immune alarms, a double edge that researchers are trying to exploit.

NodeTargetProducts hitting the node
ecDNA oncogene amplificationEGFR
TP53 loss permitsTP53
Aneuploidy / karyotype heterogeneityno target in corpus
cGAS–STINGno target in corpus
Chromosomal instabilityno target in corpus
Clonal evolution, resistanceno target in corpus
Dependencies: KIF18A, SAC, BCL-XLno target in corpus
Micronuclei → cytosolic DNAno target in corpus
Mitotic errors, WGDno target in corpus

How drugs attack it, from the pathway page: KIF18A inhibitors (sovilnesib) selectively kill CIN-high cells; phase 1/2 in ovarian and TNBC; ecDNA-directed strategies (CHK1 inhibition, transcription–replication conflict) from the Cancer Grand Challenges eDyNAmiC team; STING pathway modulation; radiation exploits CIN; Aneuploidy scores (TRACERx) as prognostic biomarkers.

Drivers, passengers & the two-hit model

Of the thousands of mutations in a tumour, only a handful (typically 2-8) actually drive it. Drivers either jam an accelerator on (oncogenes, one hit is enough) or remove a brake (tumour suppressors, both copies must go). Everything else is a passenger along for the ride.

NodeTargetProducts hitting the node
Mutation, amp, fusionKRAS
Tumour suppressorTP53
1st hit (germline/somatic)no target in corpus
2nd hit: LOH, methylationno target in corpus
Brake lost (2 hits)no target in corpus
Clonal expansionno target in corpus
Oncogene ON (1 hit)no target in corpus
Passengers, neoantigensno target in corpus
Proto-oncogeneno target in corpus

How drugs attack it, from the pathway page: Oncogene addiction is the basis of every targeted kinase inhibitor and of HER2 antibodies; Suppressor loss cannot be 'inhibited', so it is exploited indirectly: synthetic lethality (BRCA-PARP, MTAP-PRMT5), CDK4/6 for RB-intact, MDM2 for TP53-wild-type; Germline first hits drive surveillance and risk-reducing surgery in hereditary syndromes; Comprehensive genomic profiling separates drivers from passengers at diagnosis.

Drug efflux pumps (ABC transporters)

Cancer cells can install pumps in their outer membrane that throw chemotherapy back out as fast as it comes in. The same pumps guard the gut, brain and bone marrow in healthy tissue, which is why blocking them failed as a strategy and why drug designers now choose payloads the pumps cannot grip.

NodeTargetProducts hitting the node
EMT, hypoxia, NRF2 induceKRAS
Non-substrate payloads (DXd)TROP2
ABCB1 (P-gp)no target in corpus
ABCG2 (BCRP), ABCC1no target in corpus
BBB, stem cells, marrowno target in corpus
Cell deathno target in corpus
Chemo / payload entersno target in corpus
Drug exported (ATP)no target in corpus
Sub-lethal intracellular doseno target in corpus

How drugs attack it, from the pathway page: Payload selection: DXd and exatecan (T-DXd, Dato-DXd, sac-TMT) retain activity where MMAE and SN-38 are pumped out; PBD dimers and radionuclides are pump-independent; Brain-penetrant TKIs engineered to evade P-gp (lorlatinib, tucatinib, osimertinib); P-gp inhibitors (valspodar, tariquidar, zosuquidar) failed in phase 3; a museum exhibit; Collateral sensitivity and MDR-selective compounds are experimental.

Extrinsic apoptosis (death receptors)

Immune cells kill by touch: they present FAS ligand or TRAIL to a target cell, whose death receptors then trigger self-destruction from the outside in. Tumours cut this wire by deleting the receptors or over-producing decoys and blockers.

NodeTargetProducts hitting the node
CTL / NK cellCD3
tBID → mitochondriaBCL-2
Caspase-3/7 → deathno target in corpus
Decoy receptors, c-FLIPno target in corpus
DISC: FADD, caspase-8no target in corpus
FAS, DR4/DR5no target in corpus
FASL, TRAILno target in corpus
Perforin / granzyme Bno target in corpus
XIAP (IAPs)no target in corpus

How drugs attack it, from the pathway page: Checkpoint inhibitors, engagers and CAR-T all ultimately act through this wire, so caspase-8 or FAS loss confers immune resistance; SMAC mimetics (IAP antagonists) lower the threshold; birinapant, xevinapant tested with chemoradiation; DR5 agonist antibodies and TRAIL-receptor engagers, largely inactive so far; BH3 mimetics engage the mitochondrial arm downstream of tBID.

Intravasation & circulating tumour cells

Getting into the bloodstream and surviving there is brutal: cells are ripped from their neighbours, battered by flow, and hunted by NK cells. Fewer than one in a thousand survive. The ones that do travel in clusters, wear a cloak of platelets, or ride with neutrophils. Liquid biopsies catch what is left.

NodeTargetProducts hitting the node
Leaky vessels (VEGF)VEGF / VEGFR
TMEM doorway (macrophage)CSF1R
Anoikis (detachment death)no target in corpus
Clusters (plakoglobin, CD44)no target in corpus
Intravasationno target in corpus
Liquid biopsy detectionno target in corpus
NK-cell clearanceno target in corpus
Platelet cloak, NETsno target in corpus
Shear, oxidative stressno target in corpus
Surviving CTCs / clustersno target in corpus

How drugs attack it, from the pathway page: Liquid biopsy: CTC enumeration (CellSearch), ctDNA (Signatera, Guardant Reveal), fragmentomics for detection and MRD; Aspirin and low-molecular-weight heparin target platelet cloaking; aspirin reduces recurrence in PIK3CA-mutant colorectal cancer (ALASCCA); Anti-VEGF and CSF1R inhibition close TMEM doorways in models; Cluster-dissociating agents (digoxin analogues) and NK-boosting therapies are experimental.

Lipid synthesis, uptake & cholesterol

Dividing cells need membranes, and membranes are fat. Cancers switch on the fat-building enzymes most adult tissues keep off, and in fatty environments (breast, omentum, bone marrow) they also steal lipids from neighbouring fat cells. This links obesity to cancer and offers new drug targets.

NodeTargetProducts hitting the node
Mevalonate → cholesterolKRAS
SREBP (mTORC1, hypoxia)AKT
ACC → malonyl-CoAno target in corpus
AMPK / LKB1no target in corpus
CD36 uptake from adipocytesno target in corpus
Citrate → ACLY → acetyl-CoAno target in corpus
FASN → palmitateno target in corpus
Fatty acid oxidation (CPT1)no target in corpus
Obesity, insulin, IGF-1no target in corpus
PUFA → ferroptosisno target in corpus
SCD1 → membranesno target in corpus

How drugs attack it, from the pathway page: FASN inhibitor denifanstat and SCD1 inhibitors in trials; statins repurposed with mostly negative randomised data; Weight management, GLP-1 agonists and bariatric surgery reduce obesity-related cancer incidence; Exercise and dietary pattern interventions during treatment; Ferroptosis inducers exploit the lipid composition of mesenchymal and persister cells.

Menin / KMT2A (HOXA9-MEIS1 axis)

In some leukaemias a broken chromatin protein (KMT2A, once called MLL) or a mutant NPM1 keeps embryonic growth genes (HOXA9, MEIS1) switched on, so blood cells never mature. Both need a partner called menin to stay on the DNA. Menin inhibitors pull the plug and the cells mature; the first was approved in 2024.

NodeTargetProducts hitting the node
FLT3 (co-mutated; co-target)FLT3
Menin (MEN1) + LEDGFMenin
Complex bound at chromatinno target in corpus
Differentiation block → acute leukaemiano target in corpus
DOT1L (H3K79me)no target in corpus
HOXA9 / MEIS1 transcriptionno target in corpus
KMT2A fusion (MLL-r)no target in corpus
Mutant NPM1 (cytoplasmic)no target in corpus

How drugs attack it, from the pathway page: Revumenib for relapsed or refractory KMT2A-rearranged acute leukaemia (approved 2024) and NPM1-mutant AML; Ziftomenib for relapsed or refractory NPM1-mutant AML (approved 2025); Combinations with venetoclax plus azacitidine and with FLT3 inhibitors in front-line trials; Differentiation syndrome and QT prolongation need monitoring; MEN1 pocket mutations cause resistance; DOT1L inhibition (pinometostat) showed limited single-agent activity.

NK-cell recognition: missing self & stress ligands

Natural killer cells patrol for cells that have lost their identity papers (MHC-I) or that display stress flags. Cancers that hide from T cells by dropping MHC-I become visible to NK cells, unless they also shed the stress flags, wrap themselves in a second inhibitory badge (HLA-E), or soak the neighbourhood in TGF-β.

NodeTargetProducts hitting the node
CD16 ← IgG1 antibody (ADCC)HER2
TIGIT vs DNAM-1 (CD155)TIGIT
CAR-NK, IL-15, NK engagersno target in corpus
HLA-E → NKG2A (inhibit)no target in corpus
MHC-I → KIR (inhibit)no target in corpus
MICA shedding, TGF-βno target in corpus
MICA/B, ULBP → NKG2Dno target in corpus
NK cell decisionno target in corpus
Perforin, granzyme, IFN-γno target in corpus

How drugs attack it, from the pathway page: IgG1 antibodies (trastuzumab, cetuximab, rituximab) recruit NK ADCC; afucosylated antibodies (obinutuzumab, margetuximab) bind CD16 harder; IL-15 superagonist nogapendekin alfa (BCG-unresponsive NMIBC); CAR-NK and NK engagers in trials; Anti-NKG2A (monalizumab) and anti-TIGIT (tiragolumab) release inhibitory checks, with mixed phase 3 results; NK-based therapies address MHC-I-loss escape from T-cell therapies.

Oestrogen receptor signalling

In hormone-positive breast cancer, oestrogen binds its receptor, which switches on genes that make the cell divide. Every endocrine therapy cuts this chain somewhere.

NodeTargetProducts hitting the node
CDK4/6CDK4/6
ERα (ESR1)Estrogen receptor (ERα)
Androgensno target in corpus
Aromataseno target in corpus
Co-activators, FOXA1no target in corpus
Cyclin D1, MYC, PGRno target in corpus
ESR1 Y537S / D538Gno target in corpus
Oestradiolno target in corpus
Proliferationno target in corpus

How drugs attack it, from the pathway page: Aromatase inhibitors (letrozole, anastrozole, exemestane) ± ovarian suppression; SERMs (tamoxifen); SERDs: fulvestrant, elacestrant, imlunestrant, camizestrant; PROTAC degrader vepdegestrant (2026); CDK4/6 inhibitors downstream; PI3K/AKT inhibitors for cross-talk.

SWI/SNF chromatin remodelling

A machine that opens and closes DNA so genes can be read. One in five cancers has a broken part (ARID1A, SMARCA4, PBRM1), and losing one part often creates a dependence on its twin, which is the basis for new synthetic-lethal drugs.

NodeTargetProducts hitting the node
PRC2 (EZH2) antagonismEZH2
SMARCB1 loss → EZH2EZH2
ARID1A lossno target in corpus
BAF / PBAF / ncBAFno target in corpus
Enhancer access, differentiation genesno target in corpus
Nucleosome repositioningno target in corpus
SMARCA4 loss → SMARCA2 dependenceno target in corpus

How drugs attack it, from the pathway page: SMARCA2 degraders (PRT3789, PRT7732) in SMARCA4-mutant cancers (phase 1/2); EZH2 inhibition in SMARCB1-deficient tumours (tazemetostat withdrawn 2026); ATR/PARP inhibitors in ARID1A-mutant tumours (trials); FHD-286 in AML.

VEGF angiogenesis

How tumours grow their own blood supply. Low oxygen makes cells release VEGF, which tells blood-vessel cells to sprout toward the tumour.

NodeTargetProducts hitting the node
HIF-1α / HIF-2αHIF-2α
VEGF-AVEGF / VEGFR
Angiogenesis, permeabilityno target in corpus
Hypoxiano target in corpus
Immune suppression (DC, Treg)no target in corpus
PLCγ / MAPK / PI3Kno target in corpus
VEGFR2 (endothelium)no target in corpus

How drugs attack it, from the pathway page: Bevacizumab, ramucirumab (antibodies); VEGFR TKIs: axitinib, cabozantinib, lenvatinib, sunitinib; IO + VEGF combinations in RCC, HCC, endometrial cancer; PD-1×VEGF bispecifics: ivonescimab and successors; HIF-2α inhibitor belzutifan upstream in VHL-deficient RCC.

VHL / HIF oxygen sensing

The VHL/HIF pathway is how cells sense oxygen (the 2019 Nobel Prize). VHL destroys HIF when oxygen is present. Kidney cancers lose VHL, so HIF-2α is permanently on and drives blood vessel growth and proliferation.

NodeTargetProducts hitting the node
HIF-2αHIF-2α
VEGF, CAIX, GLUT1, cyclin D1VEGF / VEGFR
Angiogenesis, glycolysis, growthno target in corpus
HIF-1β (ARNT)no target in corpus
Oxygenno target in corpus
PHD hydroxylasesno target in corpus
VHL E3 ligaseno target in corpus

How drugs attack it, from the pathway page: Belzutifan (HIF-2α) in VHL disease and RCC, adjuvant with pembrolizumab (2026); VEGF-directed therapy downstream; CAIX-targeted imaging (89Zr-girentuximab) and radioligands in development.

Androgen receptor signalling

Androgen receptor signalling is prostate cancer's engine. Testosterone becomes DHT, binds the androgen receptor, and drives growth genes. Castration removes the fuel; newer pills block the receptor or the enzyme that makes fuel inside the tumour.

NodeTargetProducts hitting the node
Androgen receptorAndrogen receptor
AR-V7 / amplificationno target in corpus
CYP17A1 (adrenal/intratumoural)no target in corpus
DHTno target in corpus
GnRH → LH → testisno target in corpus
Proliferationno target in corpus
PSA, TMPRSS2-ERG, growth genesno target in corpus
Testosteroneno target in corpus

How drugs attack it, from the pathway page: GnRH agonists/antagonists (leuprolide, relugolix); CYP17A1 inhibitor abiraterone; AR antagonists enzalutamide, apalutamide, darolutamide; PARP inhibitors + ARPI in HRR-mutant disease; capivasertib + abiraterone in PTEN-deficient; AR degraders, N-terminal domain inhibitors (trials).

Autophagy

Autophagy is the cell's recycling programme. Cancer cells, especially pancreatic and RAS-driven tumours, use it to survive starvation and drug stress, which is why hydroxychloroquine, an old malaria drug that blocks it, keeps appearing in trials.

NodeTargetProducts hitting the node
Nutrient stress, KRAS/MEK inhibitionKRAS
Autophagosomeno target in corpus
Lysosome (HCQ blocks)no target in corpus
MHC-I degradation (PDAC)no target in corpus
mTORC1 (inhibits)no target in corpus
Recycled fuel → survivalno target in corpus
ULK1 / AMPKno target in corpus

How drugs attack it, from the pathway page: Hydroxychloroquine + MEK inhibitor or + KRAS inhibitor in PDAC (phase 1/2); ULK1 inhibitors (DCC-3116) in RAS-driven cancers; Autophagy inhibition to restore MHC-I and immunotherapy response (preclinical).

B-cell receptor / BTK signalling (to NF-κB)

The B-cell receptor is the survival switch of B cells. Signals from it pass through BTK to free NF-kappa-B, which keeps the cell alive. B-cell cancers hold it on; BTK inhibitors, proteasome inhibitors and lenalidomide each cut the line at a different point.

NodeTargetProducts hitting the node
BCL2, IL-6, IL-10, cyclin D → survivalBCL-2
B-cell receptor / antigenno target in corpus
CARD11 / BCL10 / MALT1no target in corpus
IKK complexno target in corpus
IRF4 / IKZF1-3 (lenalidomide)no target in corpus
IκB (destroyed by proteasome)no target in corpus
NF-κB (p65 / p50)no target in corpus
SYK → BTK → PLCγ2no target in corpus
TLR → MYD88 (L265P)no target in corpus

How drugs attack it, from the pathway page: Covalent BTK inhibitors ibrutinib, acalabrutinib, zanubrutinib; non-covalent pirtobrutinib after BTK C481S resistance; BTK degraders in trials; Proteasome inhibitors bortezomib, carfilzomib and ixazomib block IκB degradation in multiple myeloma and mantle cell lymphoma; Lenalidomide and the CELMoDs degrade IKZF1/3, cutting IRF4 and NF-κB output; BCL2 inhibition (venetoclax) removes the main survival gene NF-κB switches on.

Cancer metabolism

Cancer cells rewire how they eat. They burn glucose inefficiently but fast (the Warburg effect), gorge on glutamine and fats, and build the nucleotides and lipids needed to divide. This is why the FDG PET scan works, and why metabolism is a drug target.

NodeTargetProducts hitting the node
Mutant IDH → 2-HGIDH1 / IDH2
Aerobic glycolysis (Warburg)no target in corpus
De novo lipogenesis (FASN)no target in corpus
Glucose (GLUT1)no target in corpus
Glutamine → glutaminaseno target in corpus
Lactate export (MCT4)no target in corpus
One-carbon (SHMT2, MTHFD2) → nucleotidesno target in corpus
PI3K/AKT/mTOR, MYC, HIFno target in corpus
TCA cycleno target in corpus

How drugs attack it, from the pathway page: Antimetabolite chemotherapy (5-FU, gemcitabine, methotrexate) exploits nucleotide demand; IDH inhibitors (ivosidenib, vorasidenib) block 2-HG; Glutaminase, MCT1, FASN, and arginine-deprivation agents in trials; FDG PET images the Warburg effect; Diet and metformin trials as adjuncts.

CD47 / SIRPα (the 'don't eat me' signal)

Macrophages eat cells that look wrong, unless the cell shows CD47, a 'don't eat me' badge. Many cancers overproduce CD47 to escape being eaten. Antibodies that cover the badge should let macrophages clear the tumour; the idea works in the lab, but the leading drug failed in blood cancers because red cells wear the same badge.

NodeTargetProducts hitting the node
CD47 on tumour (and red) cellsCD47
Antigen presentation → T-cell primingno target in corpus
Phagocytosis of the tumour cellno target in corpus
Pro-phagocytic signals: calreticulin, antibody Fc (rituximab)no target in corpus
Red cells (on-target anaemia)no target in corpus
SHP-1 / SHP-2no target in corpus
SIRPα on macrophageno target in corpus

How drugs attack it, from the pathway page: Anti-CD47 magrolimab with azacitidine: phase 3 ENHANCE, ENHANCE-2 and ENHANCE-3 stopped for futility or harm; programme discontinued (2024); SIRPα-Fc fusions (evorpacept) and Fc-silent or low-affinity anti-CD47 antibodies designed to spare red cells; CD47 × CD19 or CD20 bispecifics to confine blockade to B-cell tumours; Combination with opsonising antibodies (rituximab, cetuximab, trastuzumab) to supply the 'eat me' signal.

Clonal evolution & minimal residual disease

A tumour is a population that evolves by natural selection. Treatment kills the sensitive cells and selects the rest, which is why resistance is the rule; measuring the surviving population (MRD) and adapting therapy is the counter-strategy.

NodeTargetProducts hitting the node
Truncal driver cloneTP53
Adaptive / combination therapyno target in corpus
MRD (ctDNA)no target in corpus
Relapse dominated by Bno target in corpus
Subclone Ano target in corpus
Subclone B (resistant)no target in corpus
Therapy (selection)no target in corpus

How drugs attack it, from the pathway page: ctDNA MRD to escalate or de-escalate (IMvigor011, DYNAMIC); Upfront combinations to pre-empt resistant clones (osimertinib + chemotherapy, BRAF + MEK); Adaptive therapy trials (Moffitt); Serial liquid biopsy to switch therapy at molecular progression (SERENA-6).

Clonal haematopoiesis (CHIP)

As we age, blood stem cells with cancer-like mutations quietly expand in most people. These clones raise leukaemia and heart disease risk, are accelerated by chemotherapy, and confuse blood tests for cancer DNA.

NodeTargetProducts hitting the node
DNMT3A, TET2, ASXL1, PPM1D, TP53TP53
Ageing HSCsno target in corpus
Chemo, PARPi, radioligands selectno target in corpus
CHIP clone (VAF ≥2%)no target in corpus
False-positive ctDNAno target in corpus
Inflammation → cardiovascular diseaseno target in corpus
Therapy-related MDS/AMLno target in corpus

How drugs attack it, from the pathway page: Paired white-blood-cell sequencing in liquid biopsy pipelines; Monitoring after PARP inhibitors and radioligand therapy; IL-1β/IL-6 blockade trials for CHIP-associated cardiovascular risk.

Ferroptosis & regulated cell death

Cells can die in several programmed ways. Beyond the classic apoptosis, ferroptosis kills through iron-driven fat oxidation, and drug-resistant, mesenchymal cancer cells turn out to be unusually prone to it.

NodeTargetProducts hitting the node
Apoptosis (BCL-2 family)BCL-2
Cystine import (SLC7A11)no target in corpus
Ferroptosisno target in corpus
Glutathioneno target in corpus
GPX4no target in corpus
Labile iron (Fenton)no target in corpus
Lipid peroxidationno target in corpus
Mesenchymal / persister stateno target in corpus

How drugs attack it, from the pathway page: xCT inhibitors, cyst(e)inase, sulfasalazine repurposing (early trials); Radiotherapy and IFN-γ from T cells induce lipid peroxidation; BH3 mimetics (venetoclax) exploit apoptosis; MCL-1 inhibitors in development; Persister-cell targeting after EGFR/ALK inhibitors (preclinical).

Field cancerisation

Cancer often arises from a whole region of tissue that already carries mutations, not from one rogue cell. Sun-exposed skin, smokers' airways, and Barrett's oesophagus are patchworks of mutant clones competing long before a tumour appears.

NodeTargetProducts hitting the node
Mutant clones in normal tissue (NOTCH1, TP53)TP53
Carcinogen exposure, ageingno target in corpus
Clonal competitionno target in corpus
Interception: chemoprevention, ablationno target in corpus
Progression to dysplasia → cancerno target in corpus
Second primaries, local recurrenceno target in corpus

How drugs attack it, from the pathway page: Surveillance and ablation of precancer (Barrett's RFA, cervical precancer ablation, colon polypectomy); Chemoprevention (aspirin in Lynch, tamoxifen, HPV vaccination); Field-directed therapy after resection (e.g., 5-FU cream for actinic keratosis); Molecular monitoring of fields (cytosponge, sputum, urine).

Inflammation & NF-κB

Chronic inflammation is soil for cancer: it feeds growth signals, DNA damage, and immune suppression. The NF-κB switch inside cells is the master relay, and colitis, hepatitis, and H. pylori gastritis are the clinical proof.

NodeTargetProducts hitting the node
BCR → BTK (lymphoma)BTK (Bruton tyrosine kinase)
COX-2 → PGE2no target in corpus
IKK → IκB degradationno target in corpus
IL-6 → STAT3no target in corpus
Infection, injury, obesityno target in corpus
NF-κBno target in corpus
Survival, proliferation, SASP, immune suppressionno target in corpus
TNF, IL-1β, IL-6no target in corpus

How drugs attack it, from the pathway page: Aspirin chemoprevention in Lynch syndrome (CAPP2); NSAIDs in FAP; BTK inhibitors (ibrutinib, zanubrutinib) shut NF-κB in CLL/lymphoma; IL-6/STAT3 blockade in cachexia and CRS (tocilizumab); Anti-H. pylori therapy prevents gastric cancer; HBV/HCV treatment prevents HCC.

Intrinsic apoptosis (BCL-2 family)

Intrinsic apoptosis is the cell's self-destruct switch. BCL-2 holds it shut; BAX and BAK pull it open. Venetoclax pries BCL-2 off so the switch can fire.

NodeTargetProducts hitting the node
BCL-2 / BCL-XL / MCL-1BCL-2
BAX / BAKno target in corpus
BH3-only (BIM, PUMA, NOXA)no target in corpus
Caspase-3/7 → apoptosisno target in corpus
Cytochrome c → caspase-9no target in corpus
DNA damage, oncogene stress, p53no target in corpus
Mitochondrial permeabilisationno target in corpus

How drugs attack it, from the pathway page: Venetoclax (BCL-2) in CLL, AML, mantle cell lymphoma; Next-generation BCL-2 inhibitors sonrotoclax, lisaftoclax; MCL-1 inhibitors (limited by cardiotoxicity); BCL-XL PROTACs sparing platelets; Combinations with hypomethylating agents, BTK inhibitors, menin inhibitors.

Invasion: proteases, adhesion & the invasive front

To invade, a cancer cell must grip the scaffolding around it, dissolve a path with enzymes, and pull itself forward, alone or in a chain led by a scout cell. Fibroblasts often cut the trail first. The enzyme blockers of the 1990s failed; today's targets are the grip (integrins, FAK) and the trail-makers.

NodeTargetProducts hitting the node
CAF tracksFAP
Amoeboid squeezingno target in corpus
Collective invasion (leaders)no target in corpus
EMT programme (ZEB1, SNAIL)no target in corpus
Integrins → FAK / SRCno target in corpus
Invadopodia, MT1-MMPno target in corpus
Invasive front → vesselsno target in corpus
MMP2/9, uPA → ECM breachno target in corpus
RHO–ROCK contractionno target in corpus
TGF-β, HGF, hypoxia, stiffnessno target in corpus

How drugs attack it, from the pathway page: FAK inhibitor defactinib with avutometinib (approved 2025, KRAS-mutant low-grade serous ovarian cancer); FAK inhibition also softens stroma; Broad MMP inhibitors and the integrin antagonist cilengitide failed in phase 3; lesson retained in the failure museum; Surgery and radiotherapy margins are the practical answer to local invasion; perineural and lymphovascular invasion drive adjuvant decisions; Anti-stromal strategies (FAP theranostics, Hedgehog paradox) reshape the tracks.

JAK–STAT signalling

The relay that turns cytokine signals into gene changes. Overactive in blood cancers (JAK2 in myelofibrosis), it is also the wire that carries interferon's cancer-killing message, so tumours cut it to escape immunotherapy.

NodeTargetProducts hitting the node
MHC-I, PD-L1 (STAT1)PD-L1
Cytokine / IFN-γno target in corpus
JAK1/2no target in corpus
Receptorno target in corpus
SOCS feedbackno target in corpus
STAT1 / STAT3 / STAT5no target in corpus
Survival, SASP, cachexia (STAT3)no target in corpus

How drugs attack it, from the pathway page: JAK inhibitors in myeloproliferative neoplasms and GVHD; STAT3 degraders/antisense (early trials); Anti-IL-6 (tocilizumab) for CRS and under study for cachexia; JAK-loss tumours: MHC-independent therapies (T-cell engagers, NK cells).

Microbiome–tumour interactions

The bacteria in the gut, and even inside tumours, influence whether cancer starts and whether immunotherapy works. Transplanting stool from responders has made some non-responders respond.

NodeTargetProducts hitting the node
Immunotherapy responsePD-1
Antibioticsno target in corpus
Chemotherapy degradation, inflammationno target in corpus
Colibactin → mutational signatureno target in corpus
Dendritic / T-cell primingno target in corpus
Gut microbiotano target in corpus
Intratumoural bacteriano target in corpus
Metabolites (SCFA, inosine, bile acids)no target in corpus

How drugs attack it, from the pathway page: FMT from responders with PD-1 blockade (phase 2); Defined bacterial consortia (VE800, SER-155) and diet (fibre) trials; Antibiotic stewardship around immunotherapy; Fusobacterium-targeted strategies (research).

mRNA translation (eIF4F / mTOR)

Cancer cells must make protein at furious speed. The eIF4F complex that starts protein synthesis is the funnel where growth signals converge, and drugs that pinch the funnel starve the tumour of the proteins it needs most.

NodeTargetProducts hitting the node
mTORC1AKT
4E-BPno target in corpus
eIF4Eno target in corpus
eIF4F (4E/4G/4A)no target in corpus
MNK1/2no target in corpus
MYC, cyclin D1, MCL-1 translationno target in corpus
Ribosome biogenesis (Pol I)no target in corpus

How drugs attack it, from the pathway page: mTOR inhibitors (everolimus) approved in breast, RCC, NET; eIF4A inhibitor zotatifin (eFT226) phase 1/2 with fulvestrant/abemaciclib; MNK inhibitors (tomivosertib) in NSCLC (mixed); RNA Pol I inhibitors (CX-5461, pidnarulex) in HRD cancers.

Mutagenesis & mutational signatures

Every cause of DNA damage leaves its own fingerprint in the genome: sunlight, tobacco, a faulty repair enzyme, a gut bacterium. Reading these fingerprints tells you what caused a cancer and which repair crews it is missing, which in turn predicts which drugs will work.

NodeTargetProducts hitting the node
Repair: MMR, HR, BER, NERBRCA1 / BRCA2 (HRD)
DNA lesionsno target in corpus
Drivers, neoantigensno target in corpus
Endogenous: APOBEC, ROSno target in corpus
Exogenous: UV, tobaccono target in corpus
Fixed mutationsno target in corpus
HRD, MSI, TMB biomarkersno target in corpus
Replication errorsno target in corpus
Signature (SBS, ID, CN)no target in corpus

How drugs attack it, from the pathway page: Prevention removes the mutagen: smoking cessation, UV protection, HPV/HBV vaccination, aflatoxin control; HRD signatures select PARP inhibitors and platinum; MSI/TMB select checkpoint inhibitors; Signature-aware design: avoid TMZ in MGMT-unmethylated tumours, expect APOBEC-driven resistance; Whole-genome sequencing and methylation profiling read the fingerprints.

Mutant IDH / 2-hydroxyglutarate

A single mutation in a metabolic enzyme (IDH1 or IDH2) makes cells pour out a molecule they should never make, 2-hydroxyglutarate. It jams the machinery that erases chemical marks on DNA and histones, so blood and brain cells get stuck before they mature. Pills that block the mutant enzyme let them mature again.

NodeTargetProducts hitting the node
Mutant IDH1 / IDH2 (R132, R140, R172)IDH1 / IDH2
2-hydroxyglutarate (oncometabolite)no target in corpus
Differentiation block → leukaemia, gliomano target in corpus
DNA and histone hypermethylation (G-CIMP)no target in corpus
JmjC histone demethylasesno target in corpus
TET2 DNA demethylaseno target in corpus
α-ketoglutarateno target in corpus

How drugs attack it, from the pathway page: Ivosidenib (IDH1) for relapsed AML, first-line AML with azacitidine (AGILE), IDH1-mutant cholangiocarcinoma and MDS; Olutasidenib (IDH1) and enasidenib (IDH2) for relapsed or refractory AML; Vorasidenib (dual IDH1/2, brain-penetrant) for residual or recurrent grade 2 IDH-mutant astrocytoma and oligodendroglioma (INDIGO); Differentiation syndrome is the class toxicity; steroids and hydroxyurea manage it; Combination with venetoclax and azacitidine, and with PARP inhibitors (2-HG induces a homologous-recombination defect), under study.

MYC

MYC is the most commonly amplified cancer gene, a master switch that turns on thousands of growth genes. It has no pocket for a conventional drug, so it remained 'undruggable' for 40 years; the first direct MYC drugs finally entered trials in the 2020s.

NodeTargetProducts hitting the node
CD47, PD-L1 (immune evasion)CD47
AURKA / PLK1 (stability)no target in corpus
CDK9 / BET (transcription)no target in corpus
MYC/MAXno target in corpus
Proliferationno target in corpus
Ribosome biogenesis, metabolismno target in corpus
Wnt, RAS, Notch, amplificationno target in corpus

How drugs attack it, from the pathway page: OMO-103 (Omomyc) phase 1/2 in pancreatic cancer; BET and CDK9 inhibitors reduce MYC transcription (haematologic trials); AURKA inhibitors in MYCN-amplified neuroblastoma; MYC-driven dependencies: mTOR, spliceosome, glutamine.

Notch signalling

A cell-to-cell contact signal that decides cell fate. It drives T-cell leukaemia when mutated on, acts as a tumour suppressor in some squamous cancers when lost, and its ligand DLL3 became a drug target in small-cell lung cancer.

NodeTargetProducts hitting the node
DLL3 (inhibitory; SCLC surface)DLL3
DLL/JAG ligand (neighbour)no target in corpus
HES1/HEY, MYCno target in corpus
NICD → RBPJno target in corpus
NOTCH receptorno target in corpus
γ-secretase cleavageno target in corpus

How drugs attack it, from the pathway page: Nirogacestat (γ-secretase inhibitor) in desmoid tumours; DLL3-directed tarlatamab in SCLC; DLL3 ADCs and trispecifics; NOTCH1-mutant CLL: reduced benefit from anti-CD20, informs regimen choice.

RNA splicing

Genes are cut and pasted into messages before they are used. Blood cancers often carry mutations in the splicing machinery, and the errors create abnormal proteins that could serve as targets or immune flags.

NodeTargetProducts hitting the node
Aberrant isoforms (AR-V7)Androgen receptor
Pre-mRNAno target in corpus
PRMT5 dependenceno target in corpus
R-loops, replication stressno target in corpus
SF3B1 / SRSF2 / U2AF1 (mutant)no target in corpus
Splice neoantigensno target in corpus
Spliceosomeno target in corpus

How drugs attack it, from the pathway page: Spliceosome modulators (H3B-8800 negative; next generation in development); PRMT5 inhibitors in MTAP-deleted and splicing-mutant cancers; Antisense oligonucleotides to redirect splicing (AR-V7, BCL2L1); Splice-derived neoantigen vaccines (research).

The blood–brain barrier & brain metastasis

The brain's blood vessels are sealed tight and fitted with pumps that eject most drugs. That protects the brain from poisons but also from chemotherapy and antibodies. Cancer cells that do squeeze through recruit the brain's own support cells, astrocytes, to feed and shield them.

NodeTargetProducts hitting the node
Brain-penetrant TKIs, FUSHER2
Astrocytes: Cx43, cGAMPno target in corpus
BBB: tight junctions, pericytesno target in corpus
Brain metastasisno target in corpus
CTC arrest at capillaryno target in corpus
Drugs excludedno target in corpus
Extravasation (cathepsin S)no target in corpus
P-gp / BCRP effluxno target in corpus
Vascular co-option (L1CAM)no target in corpus

How drugs attack it, from the pathway page: Brain-penetrant TKIs: osimertinib (EGFR), lorlatinib/alectinib (ALK), tucatinib (HER2, HER2CLIMB), plus T-DXd intracranial activity; Radiosurgery and hippocampal-sparing whole-brain RT; prophylactic cranial irradiation vs MRI surveillance in SCLC; Focused ultrasound BBB opening, LITT, intrathecal and intraventricular delivery for leptomeningeal disease; Astrocyte gap-junction (meclofenamate, tonabersat) and STING-axis blockade in trials.

Basement membrane & tissue barriers

Every organ keeps its lining cells behind a thin, dense sheet of protein called the basement membrane. A tumour that has not crossed it is 'in situ' and essentially curable; crossing it is the moment cancer becomes invasive.

NodeTargetProducts hitting the node
Basement membraneno target in corpus
Carcinoma in situno target in corpus
E-cadherin junctionsno target in corpus
Integrins / hemidesmosomesno target in corpus
Invasive carcinomano target in corpus
MMPs, uPA, invadopodiano target in corpus
Myoepithelial layerno target in corpus
Polarised epitheliumno target in corpus
Stroma, vesselsno target in corpus

How drugs attack it, from the pathway page: Screening and excision of in situ disease (colposcopy, DCIS surgery, endoscopic resection) before the breach; HPV vaccination removes the commonest driver of cervical in situ lesions; MMP inhibitors failed clinically in the 1990s; invasion is now approached via FAK, integrin and stromal targets; Staging (Tis vs T1) and margins encode whether the barrier was crossed.

Cancer cachexia

The wasting syndrome that kills up to a third of cancer patients: tumours send hormonal signals (GDF-15, IL-6) that switch off appetite and burn muscle and fat. The first drug to reverse it, ponsegromab, showed weight gain in 2024.

NodeTargetProducts hitting the node
Anorexiano target in corpus
GDF-15 → GFRAL (brainstem)no target in corpus
IL-6 / TNF / activinno target in corpus
Muscle proteolysis, fat lipolysisno target in corpus
Tumour + inflammationno target in corpus
Weight loss, frailty, deathno target in corpus

How drugs attack it, from the pathway page: Ponsegromab (anti-GDF-15) phase 3; Anamorelin (approved Japan), olanzapine for appetite, corticosteroids short term; Exercise and nutrition support (ESPEN/ASCO guidelines); Anti-IL-6 and activin/myostatin agents in trials.

Cancer neuroscience (nerve–tumour signalling)

Cancer neuroscience is the study of how tumours talk to nerves. Nerves grow into tumours and feed them signals; brain tumours even wire themselves into neural circuits. Cutting the conversation with common drugs such as beta-blockers is now being tested.

NodeTargetProducts hitting the node
Growth, invasion, immunosuppressionno target in corpus
Nerve ingrowth (PNI)no target in corpus
Neuron–glioma synapses (AMPA)no target in corpus
NGF, axon guidance cuesno target in corpus
Tumourno target in corpus
β-adrenergic / cholinergic signalsno target in corpus

How drugs attack it, from the pathway page: Propranolol and other β-blockers in trials (melanoma, breast, angiosarcoma); Botulinum toxin denervation trials (gastric); NGF/TrkA and AMPA-receptor (perampanel) blockade; gabapentin in glioma trials; Perineural invasion as a staging biomarker.

cGAS–STING innate sensing

cGAS-STING is the cell's alarm for DNA in the wrong place. Radiation, chemotherapy, and ADCs spill DNA into the cytoplasm; cGAS detects it, STING sounds the alarm, and interferon calls in the immune system.

NodeTargetProducts hitting the node
cGAMPno target in corpus
cGASno target in corpus
Cytosolic dsDNA / micronucleino target in corpus
ENPP1no target in corpus
Radiation, chemo, ADC payloadno target in corpus
STINGno target in corpus
TBK1 → IRF3 / NF-κBno target in corpus
Type I IFN, CXCL10 → T-cell recruitmentno target in corpus

How drugs attack it, from the pathway page: Radiotherapy (especially hypofractionated) + checkpoint inhibitors; PARP inhibitor + PD-1 combinations; STING agonists (intratumoural, systemic, antibody-conjugated); ENPP1 inhibitors; TOP1-payload ADCs + IO (ASCENT-04, EV-302 analogues).

Epithelial–mesenchymal transition & drug efflux

How a cancer cell changes shape to migrate and to shrug off drugs. Transcription factors like ZEB1 and SNAIL loosen the cell, switch on pumps that eject chemotherapy, and hide it from the immune system.

NodeTargetProducts hitting the node
ABCB1 / ABCG2 effluxno target in corpus
E-cadherin, claudinsno target in corpus
Immune exclusionno target in corpus
Invasion, metastasis, drug resistanceno target in corpus
Stemness, apoptosis resistanceno target in corpus
TGF-β, Wnt, Notch, hypoxiano target in corpus
Vimentin, N-cadherin, MMPsno target in corpus
ZEB1/2, SNAIL, TWISTno target in corpus

How drugs attack it, from the pathway page: No approved direct EMT inhibitor; Payloads with low efflux susceptibility (sac-TMT's belotecan derivative claims this) and radiation (efflux-independent); TGF-β pathway blockade (mostly failed so far); Ferroptosis inducers for mesenchymal-state cells (preclinical); Immune approaches to overcome exclusion (STING, radiation).

Hedgehog signalling

A developmental pathway that shapes embryos and is switched back on in basal cell skin cancer and some brain tumours. Blocking it cures most advanced basal cell carcinomas, but tumours learn to reactivate it downstream.

NodeTargetProducts hitting the node
GLI1/2no target in corpus
Proliferation (BCC, SHH-medulloblastoma)no target in corpus
PTCH1no target in corpus
SHH ligandno target in corpus
SMOno target in corpus
SUFUno target in corpus

How drugs attack it, from the pathway page: SMO inhibitors vismodegib, sonidegib (advanced BCC), glasdegib (AML); GLI inhibitors (arsenic trioxide, BET inhibitors) for downstream resistance (investigational); Surgery and radiation remain first line for most BCC.

Hippo–YAP/TAZ

The pathway that tells organs when to stop growing. Cancers disable it so YAP and TAZ stay in the nucleus driving growth; in mesothelioma, NF2 loss does exactly that, and the first drugs against the YAP–TEAD switch are in trials.

NodeTargetProducts hitting the node
Contact, stiffness, GPCRsno target in corpus
Growth, EMT, drug toleranceno target in corpus
MST1/2 → LATS1/2no target in corpus
NF2 (Merlin)no target in corpus
TEAD transcriptionno target in corpus
YAP/TAZno target in corpus

How drugs attack it, from the pathway page: TEAD inhibitors (VT3989, IK-930, IAG933) in NF2-mutant mesothelioma and with KRAS/EGFR inhibitors; Verteporfin repurposing (preclinical); Combination rationale: YAP bypass after MAPK inhibition.

KEAP1–NRF2 antioxidant pathway

KEAP1–NRF2 is the cell's antioxidant defence switch. Lung cancers often break the off-switch (KEAP1), leaving NRF2 permanently on, which detoxifies chemotherapy and radiation and makes these tumours resistant to almost everything.

NodeTargetProducts hitting the node
ARE genes: GSH, NQO1, effluxno target in corpus
Chemo/RT/ferroptosis resistanceno target in corpus
KEAP1 (mutated)no target in corpus
NRF2no target in corpus
Oxidative stressno target in corpus
STK11/LKB1 loss (co-mutation)no target in corpus

How drugs attack it, from the pathway page: Glutaminase inhibition (negative in KEAPSAKE); NRF2-activated prodrugs and NRF2 inhibitors (preclinical); Biomarker: KEAP1/STK11 status predicts poor IO benefit in NSCLC; CDK4/6 and mTOR combinations under study.

Organ tropism: seed and soil

Breast cancer goes to bone, lung, liver and brain; prostate cancer to bone; colon cancer to liver; uveal melanoma almost only to liver. Paget's 1889 idea still holds: where a cancer spreads depends on both the seed (the cell's programme) and the soil (the organ's welcome). Each soil has its own vicious cycle, and some are druggable.

NodeTargetProducts hitting the node
Blood-flow anatomyno target in corpus
Bone: RANKL vicious cycleno target in corpus
Brain: astrocytes, BBBno target in corpus
CTC (seed programme)no target in corpus
Denosumab, radium-223no target in corpus
Liver: Kupffer, stellate cellsno target in corpus
Lung: tenascin C, periostinno target in corpus
Organ-specific colonisationno target in corpus
SBRT, HIPEC, TAREno target in corpus
TGF-β, IGF-1 releasedno target in corpus

How drugs attack it, from the pathway page: Bone: denosumab and zoledronic acid break the vicious cycle; radium-223 and 177Lu-PSMA in bone-predominant prostate cancer; Brain-penetrant TKIs and surveillance MRI in HER2+ breast, ALK+ lung and SCLC; Regional therapy for organ-confined spread: HIPEC (peritoneum), radioembolisation and liver transplant (liver), SBRT for oligometastases; Tropism-aware adjuvant trials and exosome profiling to predict relapse site.

TGF-β signalling

A signal that stops normal cells from dividing but, once a cancer is established, switches sides: it builds scar-like stroma, walls out immune cells, and pushes cells into a migratory state.

NodeTargetProducts hitting the node
Cytostasis (early)no target in corpus
EMT, CAF activationno target in corpus
Latent TGF-β (activated by integrins)no target in corpus
SMAD2/3–SMAD4no target in corpus
SMAD4 loss (PDAC)no target in corpus
T-cell exclusionno target in corpus
TGFBR2 / ALK5no target in corpus

How drugs attack it, from the pathway page: TGF-β traps and antibodies (mostly failed: bintrafusp alfa); latent-TGF-β1-selective agents in trials; ALK5 inhibitors (vactosertib) with IO in trials; Integrin αvβ6/αvβ8 blockade to prevent activation (investigational).

The metastatic cascade

How cancer spreads: cells leave the tumour, squeeze into blood or lymph vessels, survive the journey, exit into a new organ, often sleep there for years, and finally grow. Metastasis causes about 90% of cancer deaths.

NodeTargetProducts hitting the node
Colonisation / macrometastasisno target in corpus
CTCs in circulationno target in corpus
DTC dormancyno target in corpus
Extravasationno target in corpus
Intravasationno target in corpus
Invasion (EMT, MMPs)no target in corpus
NK / T-cell clearanceno target in corpus
Pre-metastatic niche (exosomes, myeloid cells)no target in corpus
Primary tumourno target in corpus

How drugs attack it, from the pathway page: Adjuvant systemic therapy and ctDNA-guided escalation aim at DTCs before colonisation; Anti-EMT and anti-MMP drugs failed historically; TGF-β blockade is being retried in combinations; Dormancy-maintaining strategies (see tumour dormancy) are the newest idea; Metastasis-directed SBRT for oligometastatic disease.

Tumour dormancy

Cancer cells can hide in bone marrow, lung, or brain for years or decades, asleep and invisible to scans and chemotherapy, then wake up. Late relapse in breast and prostate cancer is dormancy ending.

NodeTargetProducts hitting the node
Awakening: NETs, inflammation, ageingno target in corpus
Disseminated tumour cellno target in corpus
Late relapseno target in corpus
Niche: TGF-β2, BMP7, endotheliumno target in corpus
NK / T-cell surveillanceno target in corpus
Quiescence (p38↑, ERK↓, NR2F1)no target in corpus

How drugs attack it, from the pathway page: Extended adjuvant endocrine therapy and CDK4/6 inhibitors (de facto dormancy maintenance); 5-azacytidine + all-trans retinoic acid to enforce dormancy (pilot, prostate); MRD-guided intervention at molecular relapse; NET/inflammation inhibitors to prevent awakening (preclinical).

Wnt / β-catenin

Wnt/β-catenin is a developmental pathway hijacked by colorectal cancer. Normally a destruction complex keeps β-catenin low; losing APC lets it flood the nucleus and drive growth genes.

NodeTargetProducts hitting the node
Destruction complex (APC, AXIN, GSK3β)no target in corpus
Frizzled / LRP5/6no target in corpus
MYC, cyclin D1, LGR5no target in corpus
RNF43 / RSPOno target in corpus
TCF/LEFno target in corpus
Wnt ligandno target in corpus
β-cateninno target in corpus

How drugs attack it, from the pathway page: Porcupine inhibitors (RSPO-fusion / RNF43-mutant tumours, trials); Gamma-secretase inhibitor nirogacestat in desmoid tumours (approved 2023); Tankyrase inhibitors (preclinical/early); Indirect: chemoprevention with aspirin/COX-2 in Lynch and FAP.

A node counts as drugged when a product in the corpus lists its target; a druggable node with no drug means no product in OnCo names that target, not that none exists anywhere. Nodes without a target id are pathway components (ligands, complexes, processes) that have no target page yet.