CCNE2 and breast cancer: CCNE2 silencing by siRNA (100 nM) transfection led to a decrease in cell proliferation in all of the breast cancer cell lines to ~40% viability (p = 0.001) in B474 wt, ~25% viability (p = 0.05) in BT474r, ~40% viability (p = 0.0005) in HCC1954, and ~20% viability (p = 0.003) in MDA-MB-231 cells compared to their respective controls (Fig. 8).