Objective: To explore the growth inhibiting effects on human bladder cancer by antisense RNA targeting the proliferating cell nuclear antigen (PCNA) gene.
Methods: The eukaryotic expression vector for antisense PCNA cDNA was constructed and transferred into a bladder cancer EJ cell line. The PCNA expression in the cancer cells was detected by RT-PCR and Western blotting assays. The in vitro proliferation activities of the transferred cells were observed by growth curve, tetrazolium bromide (MTT) colorimetry, tritiated thymidine ((3)H-TdR) incorporation, flow cytometry and clone formation testing, while its in vivo anti-tumor effects were detected on nude mice allograft models.
Results: After the antisense vector, pLAPSN, was transferred, cellular PCNA expression was inhibited at both protein and mRNA levels. The growth rates of EJ cells were reduced from 27.91% to 62.07% (P < 0.01), with an inhibition of DNA synthesis rate by 52.31% (P < 0.01). Transferred cells were blocked at G(0)/G(1) phases in cell-cycle assay, with the clone formation ability decreased by 50.81% (P < 0.01). The in vivo carcinogenic abilities of the transferred cancer cells were decreased by 54.23% (P < 0.05).
Conclusions: Antisense PCNA gene transfer could inhibit the growth of bladder cancer cells in vitro and in vivo, which provided an ideal strategy for gene therapy of human cancers.