PTGS2 and skin cancer: Indeed, we found that knockdown of YTHDF2 increased the expression of inflammatory mediators such as TNF-α, IL-6, COX-2/PTGS2, and IL-1β in both non-tumorigenic human HaCaT keratinocytes and normal human epidermal keratinocytes (NHEK) following UVB irradiation; it also increased the baseline expression of multiple inflammatory genes in A431 skin cancer cells (Fig. 1G–Q and Supplementary Fig. S6A–C).