However, these angiogenesis-related factors, including CD13 and integrin αvβ3, are usually differentially expressed in ovarian tumor tissues and cell lines due to the heterogeneity and genetically instability of the disease (29, 30), making it a very challenging approach to find “the optimal target”, and may also be one of the reasons for drug resistance of cancer to monotherapy. Here, ANPEP is linked to ovarian neoplasm.