{"entity":{"id":"gata6-classical-basal-marker","kind":"term","name":"GATA6 as the marker of classical versus basal-like pancreatic cancer","aka":["GATA6","GATA6 in situ hybridisation","GATA6-high","GATA6-low","GATA6 expression in pancreatic cancer"],"tldr":"GATA6 is the transcription factor that separates the two pancreatic cancer subtypes that survive every re-analysis: classical tumours express it, basal-like (squamous) tumours have lost it. A GATA6 stain on a biopsy can therefore call the subtype that predicts how a tumour answers first-line chemotherapy, although no guideline yet acts on the result.","summary":"In the COMPASS study of advanced pancreatic ductal adenocarcinoma, real-time whole-genome and RNA sequencing of biopsies classed tumours as classical or basal-like; basal-like tumours were 20% of 195 patients, responded to first-line chemotherapy in 10% against 33% of classical tumours, progressed on modified FOLFIRINOX in 60% against 15%, and had median overall survival of 5.9 against 9.3 months (O'Kane 2020). GATA6 expression by RNA in situ hybridisation separated the two with sensitivity 89% and specificity 83%, so a single stain can stand in for sequencing. GATA6 amplification marks the classical lineage (15 to 17% of tumours in the molecular table), and loss of GATA6 sits on a continuum with mutant KRAS dosage: purified whole genomes show classical and basal-like states as the two ends of a spectrum with about 12% of tumours hybrid and intermediate in survival (Chan-Seng-Yue 2020). The earlier COMPASS report (Aung 2018) had already shown that sequencing in the time frame of a treatment decision was feasible in 63 patients. What follows for care: no prospective subtype-directed trial has changed a guideline, so basal-like patients still receive the regimen they resist; GATA6 or a subtype classifier is used where a trial requires it (the record's open problems).","asOf":"2026-09-24","links":[{"label":"O'Kane et al., Clin Cancer Res 2020: GATA6 and the basal-like subtype in 195 COMPASS patients","url":"https://doi.org/10.1158/1078-0432.CCR-19-3724"},{"label":"Aung et al., Clin Cancer Res 2018: COMPASS, real-time whole-genome and RNA sequencing of 63 advanced patients","url":"https://doi.org/10.1158/1078-0432.CCR-17-2994"},{"label":"Chan-Seng-Yue et al., Nat Genet 2020: transcription phenotypes driven by genomic events (purified whole genomes)","url":"https://doi.org/10.1038/s41588-019-0566-9"}],"tags":["pancreatic-molecular"],"related":[],"cancers":["pancreatic","metastatic-pdac","locally-advanced-pdac"],"sections":[],"technologies":["rna-seq"],"targets":["kras"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["classical-vs-basal-like","basal-like","kras-allelic-imbalance","compass-study-pancreatic"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-okane-gata6-basal-like-compass-ccr-2020","paper-aung-compass-early-results-ccr-2018","paper-chan-seng-yue-pancreatic-transcription-phenotypes-nat-genet-2020"],"journals":[],"dependsOn":[],"notes":[],"category":"Biomarkers"},"route":"/terms/gata6-classical-basal-marker/","neighbours":{"cancer":[{"id":"locally-advanced-pdac","kind":"cancer","name":"Locally advanced unresectable pancreatic ductal adenocarcinoma","route":"/cancers/locally-advanced-pdac/"},{"id":"metastatic-pdac","kind":"cancer","name":"Metastatic pancreatic ductal adenocarcinoma","route":"/cancers/metastatic-pdac/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"}],"technology":[{"id":"rna-seq","kind":"technology","name":"RNA sequencing & expression profiling","route":"/technologies/rna-seq/"}],"target":[{"id":"kras","kind":"target","name":"KRAS","route":"/targets/kras/"}],"term":[{"id":"basal-like","kind":"term","name":"Basal-like breast cancer","route":"/terms/basal-like/"},{"id":"classical-vs-basal-like","kind":"term","name":"Classical versus basal-like (squamous) subtypes of pancreatic cancer, and GATA6","route":"/terms/classical-vs-basal-like/"},{"id":"compass-study-pancreatic","kind":"term","name":"COMPASS: real-time sequencing of advanced pancreatic cancer for treatment selection","route":"/terms/compass-study-pancreatic/"},{"id":"kras-allelic-imbalance","kind":"term","name":"KRAS allelic imbalance and mutant KRAS dosage in pancreatic cancer","route":"/terms/kras-allelic-imbalance/"}],"paper":[{"id":"paper-okane-gata6-basal-like-compass-ccr-2020","kind":"paper","name":"GATA6 expression distinguishes classical and basal-like subtypes in advanced pancreatic cancer","route":"/key-papers/paper-okane-gata6-basal-like-compass-ccr-2020/"},{"id":"paper-aung-compass-early-results-ccr-2018","kind":"paper","name":"Genomics-driven precision medicine for advanced pancreatic cancer: early results from the COMPASS trial","route":"/key-papers/paper-aung-compass-early-results-ccr-2018/"},{"id":"paper-chan-seng-yue-pancreatic-transcription-phenotypes-nat-genet-2020","kind":"paper","name":"Transcription phenotypes of pancreatic cancer are driven by genomic events during tumor evolution","route":"/key-papers/paper-chan-seng-yue-pancreatic-transcription-phenotypes-nat-genet-2020/"}]}}