Prognostic and predictive significance of osteopontin in malignant neoplasms

Abstract

Osteopontin is an extracellular matrix protein which is produced by different types of cells and plays an important functional role in many biological processes. This review discusses the main functions of osteopontin, its role in the progression and chemoresistance of malignant neoplasms, in the regulation of epithelial-mesenchymal transition, angiogenesis, and the body’s immune response to the tumor. The article considers the currently known mechanisms by which osteopontin affects to the survival, mobility and invasion of tumor cells, to tumor sensitivity to drug treatment, as well as the prospects for a integrated study of the predictive significance of osteopontin, markers of hypoxia, angiogenesis, epithelial- mesenchymal transition, and immunological tolerance.

Non-Alcoholic Fatty Liver Disease and Bone Tissue Metabolism: Current Findings and Future Perspectives

“…The multidirectional action of this protein is associated with its ability to interact with various molecules, including cell surface receptors, such as integrin and clusters of differentiation (CD44), intracellular signaling molecules, calcium, and heparin [55,59,91]. It has been established that OPN can exist in two isoforms: intracellular (iOPN) and secreted (OPN-s).…”

“…It has been established that OPN can exist in two isoforms: intracellular (iOPN) and secreted (OPN-s). OPN is produced by bone tissue cells (osteoclasts, osteoblasts), hepatocytes, epithelial cells, pericytes, fibroblasts, lens cells, renal tubule epithelial cells, smooth muscle cells, cells of the immune system, and also by various malignant neoplasms [55,92]. Osteopontin is also found in various body fluids, including blood, urine, bile, and breast milk [88].…”