Histone acetylation is involved in the silencing of human mutL homolog 1 (hMLH1)/mutS homolog 2 (MSH2), phosphatase and tensin homolog (PTEN), and progesterone receptor (PR), thus resulting in early carcinogenesis, more aggressive carcinomas, and resistance to hormonal treatment, respectively [15]. The gene discussed is PTEN; the disease is carcinoma.