Histone H3.3 (H3-3A)
H3.3 is one of the histone proteins DNA wraps around; a single change at position 27 (K27M) locks brain-stem and midline gliomas in an immature state and defines the diagnosis.
Overview
H3-3A (formerly H3F3A) encodes the replication-independent histone variant H3.3. The K27M substitution, and the rarer G34R/V, are the defining alterations of diffuse midline glioma, H3 K27-altered in the WHO 2021 classification, most often in the pons (DIPG), thalamus and spinal cord of children. The same mutation is found in H3-3B (H3F3B) and HIST1H3B. Dordaviprone, approved in 2025, is the first drug whose label names the H3 K27M mutation; the readout page carries the label wording and the testing route.
- Target · the protein and the cell it sits on
- Drug · antibody, small molecule, cell or radioligand
- Effect · signal, damage or kill
In plain words · H3.3 is one of the histone proteins DNA wraps around; a single change at position 27 (K27M) locks brain-stem and midline gliomas in an immature state and defines the diagnosis.
- 1 · What it is
H3.3 is one of the histone proteins DNA wraps around; a single change at position 27 (K27M) locks brain-stem and midline gliomas in an immature state and defines the diagnosis.
- 2 · What goes wrong in cancer
K27M inhibits the PRC2 methyltransferase EZH2, collapsing global H3K27 trimethylation and blocking differentiation; the mutant histone is detected by a mutation-specific antibody or by sequencing.
- 3 · How drugs use it
No product in this corpus aims at Histone H3.3 (H3-3A) yet. Drugs bind the molecule precisely: to switch it off, flag the cell for the immune system, or deliver a payload.
External identifiers
What a pathology or genomic report can say about this target, each with the thresholds approvals use.
Biology
K27M inhibits the PRC2 methyltransferase EZH2, collapsing global H3K27 trimethylation and blocking differentiation; the mutant histone is detected by a mutation-specific antibody or by sequencing.
- Diffuse midline glioma including DIPG (H3 K27M)
- Paediatric high-grade glioma (H3 G34)
Latest papers
topQuery for this target: (TITLE:"Histone H3.3" OR ABSTRACT:"Histone H3.3" OR TITLE:"H3-3A" OR ABSTRACT:"H3-3A" OR TITLE:"H3F3A" OR ABSTRACT:"H3F3A" OR TITLE:"H3.3 histone A" OR ABSTRACT:"H3.3 histone A" OR TITLE:"histone H3.3" OR ABSTRACT:"histone H3.3") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about Histone H3.3 (H3-3A), not a curated reading list.
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