CARM1 is a histone methyltransferase that methylates histone H3 at ‘Arg‐17′ (H3R17me) and plays a crucial role in nonhistone protein methylation.[37] CARM1 has been reported to dimethylate LSD1 at R838, resulting in the deubiquitination and stabilization of LSD1, and promoting the invasion and metastasis of breast cancer cells.[38] In another study, CARM1 reprogrammed cancer metabolism by methylating PKM2 at R445, R447, and R455, with changes in its enzyme activity.[23] In this study, we identified ACSL4 as a substrate of CARM1 and a specific methylated amino acid residue. The gene discussed is KDM1A; the disease is breast cancer.