Chung et al. [10] demonstrated that ERα and chronic estrogen exposure at physiological levels are essential for tumorigenesis in K14-HPVE6 or -HPVE7 transgenic mice, which developed cervical cancer with nearly 100% efficiency by 12 months, while the removal of exogenous estrogen prevented the development of cervical neoplasia and invasive cervical carcinoma (ICC). The gene discussed is ESR1; the disease is intrahepatic cholangiocarcinoma.