PTHLH and osteosarcoma: PTH and PTHrP act through PTH receptors to regulate the fate of BMSCs towards osteoblasts or adipocytes in bone (Fan et al., 2017) and to promote angiogenesis as well (Cohn-Schwartz et al., 2022), but PTH and PTHrP should not be used for a long time because of the risk of inducing osteosarcoma (Neer et al., 2001).