The presence of NPY and its receptors was described in several neoplasms, such as PCa, breast cancer, melanoma, hepatocellular carcinoma (HCC), cholangiocarcinoma, neuroblastoma, Ewing sarcoma and pituitary adenoma (Reubi et al. 2001; Kitlinska et al. 2005; Levy et al. 2006; DeMorrow et al. 2011; Hong et al. 2015; Lv et al. 2016; Pérez Tato et al. 2017). Here, NPY is linked to cholangiocarcinoma.