PRMT5 and breast cancer: PRMT1 and PRMT5 have been increasingly linked to stem cell function in normal and cancer cells (Banasavadi-Siddegowda et al., 2017, Blanc et al., 2017, Jin et al., 2016, Liu et al., 2015, Zhang et al., 2015) and breast cancer pathogenesis (Baldwin et al., 2012, Chen et al., 2017, Goulet et al., 2007, Powers et al., 2011, Yang et al., 2015).