Effect of short-hairpin RNA expression vector-mediated osteopontin RNA interference on proliferation and invasion of prostate cancer PC-3 cells

Abstract

Studies showed that osteopontin (OPN) regulates cell migration and invasion in a variety of cancers, which associates with the activities of matrix metalloproteinase (MMP)-2 and MMP-9. This study was to investigate the role of OPN in the proliferation and invasion of human prostate cancer PC-3 cells and the possible functions of IgammaB kinase (IKK) in nuclear factor kappa B (NF-kappaB)-mediated signaling pathways. OPN short-hairpin RNA (shRNA) recombinant plasmids were transfected into PC-3 cells and different concentrations of IKK inhibitors were used to inhibit the activities of IKKalpha and IKKbeta. The mRNA and protein expression levers of OPN, MMP-2, and MMP-9 were detected by real-time polymerase chain reaction (PCR) and Western blot. Cell cycle was detected by flow cytometry, cell proliferation by MTT assay, and cell invasion by Transwell chamber assay. Compared with untreated cells, the protein levers of OPN, MMP-2, and MMP-9 in OPN shRNA-transfected PC-3 cells were reduced by 55.22%, 51.71%, and 28.35%, respectively, and the ability of cell migration and invasion were decreased by 45.48% and 51.96%, respectively (P<0.05). Moreover, the inhibition of IKKbeta inhibited the expressions of MMP-2 and MMP-9. A shRNA expression vector-mediated OPN gene silencing can inhibit the malignant biological behaviors of PC-3 cells. IKKbeta may play a crucial role in the OPN-induced activation of MMP-2 and MMP-9 via NF-kappaB-mediated IkappaB/IKKbeta pathways.