Firstly, the abnormal secretion of parathyroid hormone-related peptide (PTHrP), particularly notable in squamous cancers, plays a crucial role in hypercalcemia by binding to the type I PTH/PTHrP receptor (PTHR-1) and activating pathways that promote increased calcium resorption from bones and reabsorption in the kidneys [88]. The gene discussed is PTH1R; the disease is hypercalcemia disease.