FIGURE 8.

CAGE siRNA-mediated suppression of G₁ cyclin expression, Jun AP-1 protein expression/activation, E2F-1 nuclear translocation, and cell proliferation in human cancer cell lines. A and B, protein levels of CAGE, cyclins D1 and E, and JunD and the phosphorylation level of c-Jun (A) and Rb (B) were determined in CAGE siRNA-transfected HeLa and Malme-3M cells. Cont, control. C, the level of cytosolic and nuclear E2F-1 was assessed by immunoblotting analysis after subcellular fractionation. D and E, cell proliferation was measured by MTS assay upon siRNA knockdown of CAGE in HeLa and Malme-3M cells as described under “Experimental Procedures.” *, p < 0.01 versus −doxycycline at day 4 in culture.