Tumor Immunology - The Role of Tumor-Associated Macrophages Research Paper

Tumor Immunology - The Role of Tumor-Associated Macrophages - Research Paper Example Macrophages are multipurpose cells act in response to the stimulus in diverse tumors they release various macromolecules encompassing growth factors, cytokines, chemokines, and enzymes that potentially control tumor augmentation, tumor angiogenesis, tumor invasion, and tumor metastasis. Tumor-Associated Macrophages (TAM) act upon the invasive area where TAMs sway cancer cell motility, they also act on stroma and perivascular areas where they encourage metastasis and play an imperative role in avascular and perinecrotic regions so that hypoxic TAMs accelerate angiogenesis. The present article deals with the role of TAMs in promoting tumor induction and its role as anti-tumor agent and also the role of TAMs in malignancies. It is now established that tumor cells potentially block or elude the actions of TAMs at the site of the tumor. Molecules derived from tumor cells also activate TAM elevate survival as well as the proliferation of tumor cells. On the other hand, TAMs induce tumor angiogenesis through the production of mitogens, growth factors, and enzymes. Monocyte-macrophage lineage cells get polarized activated into M1 and M2 cells. An M1 form of macrophage activation encompasses IFN-ÃŽ ³ based cytokines, GM-CSF (granulocyte-macrophage colony stimulating factor), LPS and TNF. They are distinguished by IL-12, IL-23(both high), IL-10 (low) and profuse quantity of reactive oxygen and nitrogen intermediary and inflammatory cytokines. Whereas M2 is a macrophage activation as a result of IL-4, IL13, IC (Immune complexes), IL-10 as well as glucocorticoid hormones. M2 are involved in Th2 response and perform immunoregulatory functions and plays role in tumor progression.