PTGS2 and breast cancer: More in particular, oestrogens coming from peripheral circulation and secreted in TME by CAFs and TAMs promote tumour growth, invasion, immune suppression and angiogenesis through genomic and non-genomic pathways and the other reported mechanisms in ER+ breast cancer cells; CAFs, TAMs, immune cells and APCs further contribute with production and secretion of inflammatory cytokines (IL-1, IL-4, IL-6, IL-8, IL17A, TGF-beta, TNF-alpha, NFkB, COX2 and PGE2), suppressive mediators (ROS, IDO, NO, IL-10), as well as other described mechanisms (Figure 2A).