TRIM28 and breast cancer: Interestingly, compared to parental D2.OR cells, only a modest number of genes (e.g., 81 upregulated an 63 downregulated) were significantly impacted by deleting TRIM28 expression in BORG-expressing D2.OR cells (Fig. 6c), implying that (i) the capacity of TRIM28 to regulate gene expression is greatly enhanced by its binding to BORG, and (ii) the tumor promoting properties of BORG similarly require TRIM28 to exert widespread transcriptional alterations operant in driving non-metastatic breast cancer cells to activate proliferative programs.