Research Area: Cancer Biological Activity: Zoledronic acid, one of the most potent nitrogen-containing BPs(bisphosphonates), induces antiproliferative and apoptotic effects on multiple myeloma cell lines in vitro, by activating protein kinase C, and increases the extracellular calcium concentration.Zoledronic acid and radiation caused a dosedependent and time-dependent decrease in cell viability (approximate 50% growth inhibition values were 48 μM and 20μM for 24 hours and 72 hours, respectively, for zoledronic acid and 500 cGy for radiation). [1]Zoledronate is also known as zometa. It is a treatment for hypercalcemia (high levels of calcium in the blood) caused by tumors. Tumor-induced hypercalcemia is also known as hyper-calcemia of malignancy (HCM). [2]Zoledronic acid also inhibited proliferation of human foetal osteoblastic cell line (hFOB) with an IC50 of 40 μM.In cultures of freshly isolated rabbit and human osteoclasts zoledronic acid (10-100 μM) induced morphological features similar to apoptosis and caspase-3-like activation. Osteoclastogenesis was inhibited in a dose-dependent manner with an IC50 of 15 nM in vitro in cultures of murine bone marrow cells stimulated to form osteoclasts by addition of macrophage-colony stimulating factor and ligand for the receptor activator NF-κB (RANKL). |