{"entity":{"id":"ascl1","kind":"target","name":"ASCL1","aka":["achaete-scute family bHLH transcription factor 1","Achaete-scute homolog 1","ASH1","HASH1","bHLHa46"],"tldr":"ASCL1 (Achaete-scute homolog 1) is a protein that switches other genes on and off. The public catalogues list it as a biomarker, and clinical evidence ties its variants to diagnosis, prognosis or drug response. Tied to Atypical teratoid/rhabdoid tumour.","summary":"Transcription factor that plays a key role in neuronal differentiation: acts as a pioneer transcription factor, accessing closed chromatin to allow other factors to bind and activate neural pathways. Directly binds the E box motif (5'-CANNTG-3') on promoters and promotes transcription of neuronal genes. The combination of three transcription factors, ASCL1, POU3F2/BRN2 and MYT1L, is sufficient to reprogram fibroblasts and other somatic cells into induced neuronal (iN) cells in vitro.\n\nCIViC holds 1 clinical evidence item and 0 assertions across 1 variant.","asOf":"2026-09-23","links":[{"label":"HGNC HGNC:738","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:738"},{"label":"UniProt P50553","url":"https://www.uniprot.org/uniprotkb/P50553/entry"},{"label":"NCBI Gene 429","url":"https://www.ncbi.nlm.nih.gov/gene/429"},{"label":"Ensembl ENSG00000139352","url":"https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000139352"}],"tags":["cancer-genes-wave"],"related":["civic"],"cancers":["atrt","sclc"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":["lineage-plasticity-neuroendocrine","transcription-addiction"],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: CIViC holds 1 clinical evidence items on its variants. Evidence tier \"clinical-evidence\" is the strongest of those signals.","Prevalence not recorded: none of the sources gives a positivity rate.","Small-cell lung cancer: ASCL1 is the dominant transcription factor in about 69% of tumours by immunohistochemistry, with 37% co-expressing NEUROD1, a degree of overlap that no laboratory model predicted (Baine 2020). The ASCL1 state is neuroendocrine-marker high, TTF-1 high and DLL3 high, associated with MYCL amplification and with BCL-2 dependence (Rudin 2019, Gay 2021)."],"provenance":{"editedBy":"scripts/fetch-cancer-genes.ts (CIViC, Open Targets, IntOGen, HGNC, UniProt)","editedOn":"2026-09-23"},"symbol":"ASCL1","role":["biomarker"],"evidenceTier":"clinical-evidence","sources":[{"label":"HGNC HGNC:738","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:738","note":"approved symbol, name, aliases, locus and cross-references (hgnc_complete_set.txt)"},{"label":"UniProt P50553","url":"https://www.uniprot.org/uniprotkb/P50553/entry","note":"protein name, function text, keywords and locations (REST API)"},{"label":"CIViC gene ASCL1","url":"https://civicdb.org/features/436","note":"1 evidence items, 0 assertions, 1 variants; diseases: Atypical Teratoid Rhabdoid Tumour (GraphQL API, CC0)"}],"distribution":"one-type","specificityNote":"Specificity not established: no corpus medicine is aimed at it and the catalogues give it only the role biomarker; HPA finds the RNA tissue enhanced, which says where the protein sits but not whether the tumour differs from normal tissue. HPA ASCL1: RNA tissue enhanced (brain 16 nTPM, liver 10 nTPM, pituitary gland 28 nTPM); high antibody staining in 3 normal tissues. Distribution: 1 cancer family in the corpus carries a prevalence row, label threshold or catalogue link for it (Brain and spinal cord tumours (all types)); Open Targets associates it with 0 specific cancer types at or above 0.5. (No rule of scripts/fetch-target-specificity.ts fired.)","specificitySources":[{"label":"Human Protein Atlas ASCL1 tissue","url":"https://www.proteinatlas.org/ENSG00000139352-ASCL1/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000139352 associations","url":"https://platform.opentargets.org/target/ENSG00000139352/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:738","ensembl":"ENSG00000139352","uniprot":"P50553","entrez":"429","firstDescribed":1993,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Ball D.W. et al, Proc. Natl. Acad. Sci. U.S.A, 1993, \"Identification of a human achaete-scute homolog highly expressed in neuroendocrine tumors\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/8390674/","biology":"Transcription factor that plays a key role in neuronal differentiation: acts as a pioneer transcription factor, accessing closed chromatin to allow other factors to bind and activate neural pathways. Directly binds the E box motif (5'-CANNTG-3') on promoters and promotes transcription of neuronal genes. The combination of three transcription factors, ASCL1, POU3F2/BRN2 and MYT1L, is sufficient to reprogram fibroblasts and other somatic cells into induced neuronal (iN) cells in vitro. Plays a role at early stages of development of specific neural lineages in most regions of the CNS, and of several lineages in the PNS. Essential for the generation of olfactory and autonomic neurons. Acts synergistically with FOXN4 to specify the identity of V2b neurons rather than V2a from bipotential p2 progenitors during spinal cord neurogenesis, probably through DLL4-NOTCH signalling activation. Location: Nucleus (UniProt). Locus 12q23.2 (HGNC).","whereFound":["Atypical teratoid/rhabdoid tumour: CIViC evidence names this disease"],"targetClass":"transcription","prevalence":[]},"route":"/targets/ascl1/","neighbours":{"collection":[{"id":"civic","kind":"collection","name":"CIViC","route":"/collections/civic/"}],"cancer":[{"id":"atrt","kind":"cancer","name":"Atypical teratoid/rhabdoid tumour (ATRT)","route":"/cancers/atrt/"},{"id":"sclc","kind":"cancer","name":"Small-cell lung cancer","route":"/cancers/sclc/"}],"pathway":[{"id":"lineage-plasticity-neuroendocrine","kind":"pathway","name":"Lineage plasticity & neuroendocrine transformation","route":"/pathways/lineage-plasticity-neuroendocrine/"},{"id":"transcription-addiction","kind":"pathway","name":"Transcriptional machinery & addiction","route":"/pathways/transcription-addiction/"}],"paper":[{"id":"paper-labrecque-mcrpc-phenotypes-jci-2019","kind":"paper","name":"Molecular profiling stratifies diverse phenotypes of treatment-refractory metastatic castration-resistant prostate cancer","route":"/key-papers/paper-labrecque-mcrpc-phenotypes-jci-2019/"},{"id":"paper-rudin-sclc-molecular-subtypes-nat-rev-cancer-2019","kind":"paper","name":"Molecular subtypes of small cell lung cancer: a synthesis of human and mouse model data","route":"/key-papers/paper-rudin-sclc-molecular-subtypes-nat-rev-cancer-2019/"},{"id":"paper-gay-sclc-subtypes-inflamed-cancer-cell-2021","kind":"paper","name":"Patterns of transcription factor programs and immune pathway activation define four major subtypes of SCLC with distinct therapeutic vulnerabilities","route":"/key-papers/paper-gay-sclc-subtypes-inflamed-cancer-cell-2021/"},{"id":"paper-baine-sclc-subtype-immunohistochemistry-jto-2020","kind":"paper","name":"SCLC subtypes defined by ASCL1, NEUROD1, POU2F3, and YAP1: a comprehensive immunohistochemical and histopathologic characterization","route":"/key-papers/paper-baine-sclc-subtype-immunohistochemistry-jto-2020/"}]}}