PTGS2 and neoplasm: Due to the significant differences in their relative abundancy, i.e. FRCs being less than 0.1% of the LN cellular constituents as compared with the dominant presence of tumors and high abundancy of MDSCs within the TME, it is not surprising that under physiological conditions, FRCs only impose modest T cell suppression by elevating T cell activation threshold as compared with the “global” COX-2/PGE2 activity in the TME imposed by tumors and MDSCs under pathological conditions, which compels detrimental immunosuppression on tumor infiltrating T cells23, 33.