Review: The tumor microenvironment of melanoma

Aim and objectives: Melanoma is one of the most complex skin cancers based on its numerous somatic mutations and chromosomal instability. Besides the traditional causative factors, such as ultraviolet radiation, or genetic factors, recent studies showed that melanoma highly depends on its adjacent microenvironment. A malignant tumor, like melanoma, is composed of oncogenic cells, regular cells (melanocytes, macrophages, mast cells, keratinocytes, and others), the supporting stroma, which includes fibroblasts, endothelial cells, immune cells, soluble molecules, and the extracellular matrix (ECM). This article aims to present the tumor microenvironment's main functions in the development or progression of melanoma. Material and methods: we have studied some of the most recent 30 articles based on the role of the microenvironment in melanoma. Results: After analyzing the most recent articles regarding melanoma’s tumor microenvironment (TME) and its impact, we have found that the cells that comprise the TME can affect melanoma’s onset or progression. TME’s cells actively interact with each other and have many functions, from tumor-suppressing roles to the initiation or progression of melanoma. Conclusions: Understanding the complex interplay between tumor cells, and systemic mediators of disease progression is critical for the rational development of effective melanoma treatments. Each cell involved in the TME can play an important role either in the onset or advancement of melanoma with the help of certain mutagenic factors.