To assess the contribution of p62 in promoting breast cancer stem-like properties, we used short-hairpin RNA (shRNA) to mediate p62 suppression in MDA-MB-231 and SUM149 cells with relatively higher endogenous p62 expression levels, and lentivirus to facilitate ectopic overexpression of p62 in MCF-7 cells which displayed lower p62 levels (Supplementary Figure 2). This evidence concerns the gene SQSTM1 and breast cancer.