Dendritic cells and melanoma tumorigenesis: an insight.

Dendritic cells, distinct class of leukocytes, are professional antigen-presenting cells. They are characterized by their ability to migrate through tissues where they can take up, process, and present antigens. They can interact with, stimulate, and direct T-lymphocyte responses. As such, they are capable of triggering a primary T cell response. Evidence suggest that DCs can elicit strong antitumor immunity. Melanoma is an aggressive malignancy with a poor prognosis. In these tumors, there is a reduced density of DCs in the epidermal, intratumoral and peritumoral sites. This seems to share to a defective T-cell response and ultimately to a poor prognosis in these tumors. Since 1975, more than 806 papers appeared in the literature with melanomas and DCs as keywords. However, in spite of these extensive investigations, a lack of side-by-side analysis of these studies has resulted in tentative conclusions that merely offer a first glimpse at the role of DCs in melanoma. To remedy this issue, this review seeks to examine the background information about DCs including their derivation, morphologic features, functional properties, growth characteristics, and differentiation pathways. This review provides insights into DCs status in the skin, and their roles in melanoma. It also sheds light on the possible use of DCs in melanoma therapy.