Recent studies have identified subtypes of small cell lung carcinoma (SCLC) defined by the RNA expression of ASCL1, NEUROD1, POU2F3, and YAP1 transcriptional regulators. There are only limited data on the distribution of these markers at the protein level and associated pathologic characteristics in clinical SCLC samples.Are SCLC subtypes defined by distinct gene expression profiles?
One key insight emerging from complementary human and mouse investigation is the classification of SCLC subtypes defined by distinct gene expression profiles. Several therapeutic targets that are the focus of recent, active and planned clinical trials appear to differ in subtype specificity.How many types of SCLC are there?
Consensus clustering of either the SCLC methylome or RNA sequencing (RNA-seq) in primary human SCLC was consistent with at most four subtypes.Is there a subtype of SCLC with high ATOH1 expression?
Within the less/non-neuroendocrine category, a rare subtype with high expression of the transcription factor ATOH1 has been reported79. SCLC-A tumours have been proposed to comprise two distinct subtypes (SCLC-A and SCLC-A2), with SCLC-A2 distinguished from SCLC-A by its expression of other factors, such as HES1 (REF.131).