More recently, P2Y12 expression has been also described in breast cancer cell lines (Sarangi et al., 2013). The baseline expression of the receptor protein was low in both normal breast epithelium (MCF 10A cells) and in human breast cancer cell lines, namely MCF7 and MDA-MB-231 (Sarangi et al., 2013). Interestingly, as for the glioma cells, the P2Y12 protein levels were enhanced by serum starvation. Also, cell treatment with cisplatin, a well-known chemotherapeutic agent, enhanced P2Y12 expression in breast cancer cells (Sarangi et al., 2013; Dasari and Tchounwou, 2014). The inhibition of P2Y12 reduced cisplatin-mediated increase of hypoxia-inducible factor 1-alpha, a factor involved in the resistance to cytotoxic therapy (Ai et al., 2016; Zhao et al., 2016), in angiogenesis and in metastatic processes (Choi et al., 2016; Wang et al., 2016).