<prompt> Answer this question truthfullyWhat are the typical serum levels of parathyroid hormone PTH and parathyroid hormone-related protein PTHrP in hypercalcemia of malignancy PTHrP?  <response>: <reason> Hypercalcemia of malignancy PTHrP is characterized by low serum levels of parathyroid hormone PTH and high serum levels of parathyroid hormone-related protein PTHrP. PTHrP is a hormone produced by some cancer cells that mimics the effects of PTH, leading to increased calcium release from bones and elevated calcium levels in the blood. Low PTH levels in hypercalcemia of malignancy may be due to the negative feedback effect of high calcium levels on PTH production, while high PTHrP levels are a hallmark of this condition. Treatment for hypercalcemia of malignancy may involve addressing the underlying cancer, as well as medications to lower calcium levels and manage symptoms. 