Immune escape mechanisms in malignant melanoma (Review)

Malignant melanoma is an antigenic tumor recognized by specific lymphocytes . Several melanoma-associated antigens have been shown to cause tumor rejec tion in vitro. Escape from immunosurveillance by melanoma cells is the resu lt of several mechanisms such as total loss or decreased expression of HLA antigens, alterations in the expression of tumor-associated antigens or def iciencies in the antigen-processing machinery. Additional important feature s include the influence of endogenous and exogenous cytokines such as inter ferons or interleukins and expression of adhesion molecules or co-stimulato ry molecules. All these factor have to be considered for the development of new immunoregulatory treatment modalities against advanced melanoma.