By combining whole-genome microarray expression analysis performed on lung cancer cell lines with ChIP-Seq data designed to identify conserved transcriptional targets of ASCL1, we discovered an ASCL1 target 72-gene expression signature that (i) identifies neuroendocrine differentiation in NSCLC cell lines, (ii) is predictive of poor prognosis in resected NSCLC specimens from three datasets, and (iii) represents novel "druggable" targets.
CLCA2, HMGB3, L587S and ASH1 were identified in lung cancer tissues using genetic subtraction, microarray and quantitative PCR, and found to be specific and complementary for detection of non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC).
Subsequently, HASH1 expression in RNA isolated from biopsies from SCLC patients (n = 4) was compared with biopsies from non-SCLC (NSCLC) patients (n = 2) or normal bronchus (n = 2).