To understand the alteration in overall m6A levels during cancer development, we estimated the m6A W, E, R1 and R2 signatures based on the expression of writer-associated genes (METTL3, METTL14, METTL16, WTAP, KIAA1429, RBM15, RBM15B, CBLL1, and ZC3H13), eraser-associated genes (FTO and ALKBH5), and reader-associated genes (R1: YTHDF1, 2, and 3; R2: IGF2BP1, 2, and 3). Here, FTO is linked to cancer.