Relevant alterations range from genetic aberrations (e.g. AR-gain or mutations) [22] to transcriptional changes such as alternative splicing (e.g. AR-V7) [23–25], expression of PSMA and SLFN11 [26, 27], or upregulation of neuroendocrine markers (e.g. SYP, CHGA, NCAM1, and DLL3) in cancers cells [8]. The gene discussed is DLL3; the disease is cancer.