PRMT5 and breast cancer: WDR77, also known as methylosome protein 50 (MEP50), serves as the primary protein partner of PRMT5, influencing its catalytic activity and substrate specificity.[32] The PRMT5/WDR77 complex exhibits higher methyltransferase activity than PRMT5 alone, potentially due to WDR77's positive allosteric effect on the binding of PRMT5 to proteins or SAM substrates or its role in presenting protein substrates to PRMT5[33] Overexpression of WDR77 is associated with poor prognosis in lung and breast cancer,[34, 35, 36] making the PRMT5/WDR77 complex an attractive therapeutic target.