INSM1 and cancer: Although the analyses performed in the current study did not provide functional evidence for epigenetic regulation of, for example, DLL3, NCAM1, or INSM1, in NE lung cancers, it has been reported in hepatocellular carcinoma that DLL3 appears to be regulated by promoter methylation (silenced by hypermethylation), and that, for example, 5-Aza-2′-deoxycytidine treatment of cancer cell lines could reactivate expression of the gene [26,27].