Post-translational modifications are also a central focus in the field of epigenetics. Arginine methylation is one of the key mechanisms for the epigenetic regulation of transcription, which can activate or repress gene expression depending on the site and type of arginine methylation on histone tails. Aberrant levels of histone arginine modifications have been associated with cancer development. Emerging studies have also shown that arginine methylation does not function alone but work together with other epigenetic modifications to orchestrate transcription. Our recent study revealed that PRMT2/4-mediated arginine methylation of BRD4 is required for BRD4 interaction with acetylated histone to control a unique transcription program in breast cancer (Liu et al. Science Advances, 2022). In the future, we are interested in further understanding the roles of protein arginine methylation in epigenetic regulation by identifying histone arginine demethylases and exploring cross-talks between arginine methylation and other epigenetic modifications in chromatin dynamics, transcriptional regulation, and cancer development.