Knockdown of FTO increased the methylation of m6A in the intrinsic genes of key primary melanoma cells such as PD-1 (PDCD1), CXCR4, SOX10, and so on, leading to increased attenuation of RNA in m6A reader YTHDF2, suggesting that FTO inhibition combined with anti-PD-1 blocking may abate the resistance of melanoma immunotherapy (Yang et al., 2019). Here, PDCD1 is linked to melanoma.