The role of osteopontin in the development and metastasis of melanoma

Melanoma is a highly heterogeneous tumor. The incidence of melanoma increases with age and its long-term prognosis is poor. The treatment of melanoma includes surgical removal, chemotherapy and immunotherapy; however, the effect of these treatments is limited on mutated melanoma. Osteopontin is an extracellular protein which is expressed in numerous kinds of cells; it is related to the proliferation and invasion of cancer cells as well as the development of tumor microenvironment. The relationship between osteopontin and metastasis of melanoma has been clarified in recent years. This review focuses on the expression of osteopontin in patients with melanoma and associated signaling pathways involved in development and metastasis of melanoma; the potential role of osteopontin in immune modulation and prognosis prediction is also discussed here.