We identified “stem-like” cell populations (CD44+ and CD44+/CD133+) in aggressive metastatic prostate cancer subtypes, which was confirmed by the RNA-seq and subclonal overexpression of several EMT markers (VIM, HAS3, S100A6, ANXA2P2, ANXA2, ANXA3, AHNAK2, LOXL2, TGFB, TGFBR2, UCHL1, CD44, CD55, and CD109). This evidence concerns the gene HAS3 and prostate cancer.