BMI1 and cancer: The YB1 transcription factor induces the stemness-related gene expression and epithelial-mesenchymal transition in hepatocellular carcinoma (Chao et al., 2017) while YY1 is associated with transcription factor (SOX2, OCT4, BMI1) expression in cancers suggesting a co-regulatory role in cancer stem cells (Kaufhold et al., 2016; Johnson et al., 2019).