Abstract: The present invention discloses the use of PSP-94, PCK3145 and other derivatives and biologically active analogues for treating a patient having a condition such as metastasis, metastatic cancer, a condition associated with elevated levels of parathyroid hormone-related protein (PTHrP), PTHrP-induced osteolysis and/or hypercalcemia of malignancy. These compounds were found to be effective treatment modalities for bone metastasis caused by prostate cancer. Furthermore, decrease in cellular and plasma PTHrP levels as well as plasma calcium levels observed by treatment with such compound can serve as useful biochemical markers for monitoring the efficacy of these anti-metastatic compounds.

Abstract: The present invention discloses the use of PSP-94 for treating a patient suffering from hypercalcemia of malignancy. Prostate secretory protein of 94 amino acids (PSP-94) is known to serve as prognostic marker in hormone-dependent prostate. In the current study the effect of PSP-94 on prostate cancer growth, metastases to the skeleton and hypercalcemia of malignancy was examined. A marked dose-dependent decrease in primary tumor volume was seen in experimental animals receiving PSP-94. Furthermore, while control animals routinely developed hypercalcemia due to PTHrP production, treatment with PSP-94 led to a near normalization of plasma calcium and a marked reduction in PTHrP production as determined by radioimmunoassay and immunohistochemistry. Results obtained demonstrate the ability of PSP-94 to be an effective treatment modality for prostate cancer. Furthermore, decrease in plasma PTHrP and calcium levels can serve as useful biochemical markers for monitoring the efficacy of this novel anti-tumor agent.