Hypermethylation of CpG islands in the PTEN promoter is found in various types of cancers, including breast, lung, ovarian, cervical, colorectal, and thyroid cancer, as well as melanoma, gastric carcinoma, and metabolic syndrome [67,68,69,70,71,72,73,74,75,76,77,78]. The gene discussed is PTEN; the disease is cancer.