Biology, Therapy and Implications of Tumor Exosomes in the Progression of Melanoma

Cancer is the second leading cause of death in the United States, and about 6% of the estimated cancer diagnoses this year will be melanoma cases. Melanomas are derived from transformation of the pigment producing cells of the skin, melanocytes. Early stage melanoma is usually curable by surgical resection, but late stage or subsequent secondary metastatic tumors are treated with some success with chemotherapies, radiation and/or immunotherapies. Most cancer patients die from metastatic disease, which is especially the case in melanoma. A better understanding of tumor metastasis will provide insights and guide rational therapeutic designs. Recently, the importance of melanoma-derived exosomes in the progression of that cancer has become more apparent, namely, their role in various stages of metastasis, including the induction of migration, invasion, primary niche manipulation, immune modulation and pre-metastatic niche formation. This review focuses on the critical roles that melanoma exosomes play in the progression of this deadly disease.