PTHLH and plasma cell myeloma: This pathological process occurs in both osteolytic Metastasis, such as multiple myeloma and breast cancer, where bone resorption predominates, and in osteoblastic lesions, typified by prostate cancer, where overexpression of parathyroid hormone-related protein promotes osteoblast precursor differentiation while concurrently driving osteoclastogenesis, sustaining high skeletal turnover despite radiographic sclerosis [51,52].