RSU1 and breast cancer: A more recent study, performed in breast cancer cell lines showed that RSU1 is upregulated in more aggressive and highly invasive MDA-MB-231 breast cancer cells compared to the non-aggressive MCF-7 breast cancer cells, both at the mRNA and protein level, which indicates a deregulation in RSU1 expression in the more cancerous cell line, perhaps as a compensatory mechanism to reduce cell proliferation rate.