EPOR and neoplasm: Yasuda et al. [81] proposed the presence of a paracrine or autocrine EPO–EPOR loop and its contribution to tumorigenesis in female reproductive organs, which was based on the fact of the mitogenic action of EPO as well as on the finding that injection of sEPOR or EPO-monoclonal antibody into blocks of tumor specimens is followed by apoptosis of tumor and ECs.