HYPERCALCEMIA OF MALIGNANCY - THE CENTRAL ROLE OF PARATHYROID HORMONE-RELATED PROTEIN

Hypercalcemia is the most common metabolic complication of cancer. Mal ignancy-associated hypercalcemia (MAHC) can be divided into two syndro mes, humoral hypercalcemia of malignancy (HHM) and local osteolytic hy percalcemia (LOH), based on whether a circulating hormone or local par acrine factors mediate accelerated bone resorption. Over the past deca de, studies have shown that parathyroid hormone-related protein is the cause of the HHM syndrome, and recent data suggest that this protein may also play a paracrine role in some patients with local osteolytic hypercalcemia. Study of the regulation of parathyroid hormone-related protein gene expression is beginning to shed some light on the molecul ar mechanisms responsible for this common clinical problem.