Construction of antisense RNA expression plasmid for u-PAR and its transfection to highly invasive PC-3M cell subclones.

To evaluate the specific inhibition of antisense u-PAR on the u-PAR expressions in highly invasive cell subclones and to determine its blocking function in the invasion by those cells, a cDNA fragment of u-PAR obtained by RT-PCR was inserted into a plasmid vector named pcDNA3 in antisense orientation. Then the antisense u-PAR recombinant was transfected into highly invasive cell subclones. The u-PAR expression in neo-resistant cells was examined by RT-PCR and immunohistochemical assay. Compared to the control cells, the content of mRNA and protein of u-PAR in transfected cells decreased sharply, and the rate of inhibition was 53% and 73%, respectively, indicating that an antisense u-PAR might have played a specific inhibitory role in its expression in the cells, which may provide a good cell model for making further investigation of the inhibitory effects of the antisense u-PAR on invasion in highly invasive cell subclones of human prostate carcinoma.