Eight of these genes, including SOX1 [17–20], WIF1 [21, 22], ACRC [23], ADCY5 [24], BCAP31 [25], NKX6-2 [26], PLK5P [27], and PRSS21 [28], have been reported to be hypermethylated in cancers. The gene discussed is PRSS21; the disease is cancer.