PTHLH and breast cancer: Interestingly, activation of the CaSR can act synergistically with TGFβ to increase PTHrP secretion in hepatocytes as well as MCF-7 and MDA-MB-231 breast cancer cells, a characteristic that may contribute to the pathogenesis of bone metastasis (Sanders et al., 2000; Organista-Juarez et al., 2013).