PTEN and obesity due to melanocortin 4 receptor deficiency: PTEN, one of the most well-known antioncogenes, is lost frequently in malignancies, including EOC [27], PI3K/Akt is a key downstream pathway of PTEN, which has a strong modulation capacity on cell growth, differentiation, proliferation, migration, as well as pro- or anti-inflammatory and metabolism, such as insulin resistance associated with obesity [28].