CCL2 and renal fibrosis: For example, decreased occupancy of H2AK119 monoubiquitination (H2AK119Ub) at the TGF-β and monocyte chemoattractant protein-1 (MCP-1) promoters may upregulate TGF-β pathway-related factors in diabetic kidneys, activate fibrosis-related signals, and accelerate renal fibrosis (134).