Since the DNA methyltransferase DNMT3b plays an important role in methylation of cancer-related genes, and HOXB13 was reported to be a target gene of DNMT3b in primary colorectal tumors [26], [27], we speculated that DNMT3b may also be involved in HOXB13 transcriptional repression in DU145 cells. The gene discussed is DNMT3B; the disease is cancer.