The tumor microenvironment is rich in molecules such as cyclooxygenase 2 (COX-2), vascular endothelial growth factor (VEGF), interleukin-6, interleukin-10, stem cell factor-1, macrophage-colony stimulating factor (M-CSF), and transforming growth factor (TGF-β) that are involved in the suppression of immune system functions and promote activation, invasion, and metastasis of tumors [48]. This evidence concerns the gene PTGS2 and neoplasm.