As noted in the Introduction, the CaSR has been shown to regulate PTHrP production by several cell types, such as astrocytes, ovarian epithelial cells, cytotrophoblasts, hepatocytes, osteoblasts, prostate cancer cells, CaSR transfected HEK293 cells, and breast cancer cells (Brown and MacLeod, 2001; Chattopadhyay, 2006; Reyes-Ibarra et al., 2007; Wysolmerski, 2012; Organista-Juarez et al., 2013). Here, PTHLH is linked to breast cancer.