Alendronate and Osteonecrosis of the Jaw

Objectives: Osteonecrosis of the jaw (ONJ), a necrotic bone disease unique to the craniofacial region, is often observed among cancer patients treated with bisphosphonate (BP)-based chemotherapy and becomes a costly and debilitating source of pain and reduced quality of life. Elucidation of clinicopathological mechanism and biomarkers of ONJ that can indicate probable disease course would allow for better assessment of treatment strategies for individual patients. To address our overall goal of identifying novel diagnostic and prognostic strategies for ONJ, this study specifically aims to understand the alendronate (ALN) treatment-induced perturbation of bone proteome and microenvironmental pathophysiology of ONJ using targeted molecular analyses and computational approaches based on an in vitro cell culture system. This study also focuses on identifying proteome perturbation and potential molecular biomarkers during ONJ development. Methods: To understand the molecular mechanisms underlying ONJ, an unbiased and global proteomics approach combined with big data analysis using bioinformatics was applied. Biochemical and functional analyses were followed to tease out the mechanisms regulated by ALN treatment. Results: The current findings from our global proteomics study and biochemical analyses suggested that the RIPK3/Wnt/GSK3/β-catenin signaling pathway is significantly perturbed upon alendronate treatment, resulting in abnormal angiogenesis/inflammation/bone anabolism/remodeling/bone mineralization in the in vitro cell culture system. Conclusion: This investigation on potential key signaling mechanisms underlying ONJ will provide a rational basis for suppressing BP-induced ONJ and novel therapeutic strategies against ONJ.