KDM1A and breast cancer: LSD1 is overexpressed in several subtypes of BC and functions as an oncogene mediating proliferation, differentiation, invasion, and metastasis of BC cells (Figure 3; Tables 1–3) (Ma et al., 2016; Feng et al., 2017; Yang et al., 2018a; Hu et al., 2019; Zhou et al., 2021a; Ji et al., 2021).