PTGS2 and neoplasm: Increase of hypoxia-induced factors mediating tumor progression and treatment resistance [62,63,93]Hypoxia initiates recruitment of suppressive and proangiogenic ICs and results in upregulation of PD-L1 on TCs and other cell types [66,115]CAFs and TCs substitute for interrupted TEC signaling by secretion of HGF, EGF and SDF-1, by inducing expression of the corresponding receptors and by direct interaction [63,92,97,123]COX2 produced PGE2 is a mediator of resistance to VEGFR-inhibiton [106]