The S-phase kinase-associated protein-2 (SKP2) plays a strategic
role in ubiquitin-mediated proteolysis, which effects in the
development of cells from inactivity to proliferative state. SKP2 is
overexpressed in a variety of tumor. In this study, we used small
interfering RNAs (siRNAs) to inhibit the SKP2 expression in Breast
cancer cells preface investigate the role of SKP2 in breast
tumorigenesis. Two Breast cancer cell lines (MCF-7 and T47D) were
transfected with siRNAs targeted against SKP2. Our results showed
one SKP2-siRNA specifically and efficiently reduced the levels of the
SKP2 protein by 90% 48 h after transfection in MCF-7 cell line. In the
transfected cells, p27 protein was accumulated inversely related to
Skp2 siRNA transfected Breast cells. Skp2 siRNA inhibited the cell
growth of breast cells in vitro. Moreover, Skp2 siRNA also suppressed
tumor proliferation in vivo. Our results suggest that siRNA-mediated
gene silencing of Skp2 can be a potent tool of cancer gene therapy for
suppression of p27 degradation in breast cancer