Paradoxical effects of cytokines in cancer

The relationship between cytokines and cancer is multiple and bidirectional. First cytokines can directly influence carcinogenesis angiogenesis and metastasis throughmodification of the tumor phenotype. Then during tumor progression the altered expression of cytokines produced by tumor cells in the tumor microenvironment causes an immunosuppressive state.Cytokines also play a role in stimulating the immune system by generating a specific antitumor response. Finally the use ofcytokines as antitumor agents has been shown to improve the clinical response in cancer patients. Thus cytokines present a molecular basis formolecular basis for improved immunotherapeutic approaches to cancer.