Characterization of Arginine Methylation in Cancer Cell using LC-MS/MS

Protein arginine methyltransferase 9 (PRMT9) activity has been observed to be elevated in cancer patients, including many types of leukemias, correlating with poor prognosis and decreased response to immune checkpoint inhibitors. By targeting PRMT9, we can eliminate PRMT9-proficient/immune-cold cancers via mechanisms such as Type-I Interferon associated immunity. Deleting PRMT9 resulted in a decrease in arginine methylation of regulators involved in RNA translation and DNA damage response. Through global proteomics and SILAC methyl(R) enrichment, we characterized arginine methylation changes in AML cell lines via LC-MS/MS.