The Impact of M1/M2 Tumor Associated Macrophage (TAM) Polarization on Cancer Progression and Prognosis Prediction
Inflammatory response in the tumor micro-environment may facilitate the metastatic process
(1). Macrophages are pivotal members of the inflammatory cells and the innate immune system
within the tumor stroma. Tumor-associated macrophages can release growth factors, cytokines
and inflammatory mediators that may facilitate cancer cell invasion, migration,
angiogenesis, tumor progression or metastasis (1-5). A lot of studies showed TAM encounter
factors that most frequently polarize them toward M2 type macrophage (1,4-5). It is
interesting that in vitro studies macrophages have the potential to kill tumor by
appropriate stimulation but these macrophage belonged to M1 and were not present in most
tumor tissue (6). Some drugs target to suppress TAM have the promising results in animal
models (7-9). Switching the TAM phenotype from M2 to M1 may promote anti-tumor activity
(10). In this study we will correlate TAM M1/M2 ratio and patients' prognosis, the gene
expression pattern of TAM.
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Observational Model: Case Control, Time Perspective: Prospective
outcome (treatment response and mortality)
Department of Internal Medicine and Emergency Medicine, National Taiwan University Hospital
Taiwan: Department of Health