Antitumor effects of PLGA nanoparticles encapsulating the human PNAS-4 gene combined with cisplatin in ovarian cancer

Human PNAS-4 (hPNAS-4), as a pro-apoptotic gene, can inhibit tumor growth when overexpressed in some malignant cells. Poly (lactic-co-glycolic acid) (PLGA) was used as a gene transfer vector due to the advantage of sustained release, nontoxicity and biodegradability. In this study, we aimed to investigate the effect of PLGA nanoparticles encapsulating hPNAS-4 combined with cisplatin (DDP) on ovarian carcinoma. Expression of hPNAS-4 was determined by RT-PCR. Mice bearing intraperitoneal ovarian carcinomas were treated with PBS, pVAX-PLGA nanoparticles (P-P), pVAX-hPNAS-4-PLGA nanoparticles (PhP-P), DDP and PhP-P plus DDP, respectively. Intraperitoneal tumors were weighed to assess the antitumor efficacy. The percentage of proliferative cells and apoptotic cells was evaluated by Ki-67 staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. The anti-angiogenic effects were detected by CD31 staining and the alginate-encapsulate assay. Overexpression of hPNAS-4 was detected by RT-PCR in the PhP-P and PhP-P plus DDP groups. PhP-P exerted significant antitumor activity through induction of apoptosis, inhibition of cell proliferation and suppression of angiogenesis, compared with treatment with P-P or PBS alone. The combination of PhP-P with DDP showed enhanced antitumor activity compared with therapy of PhP-P or DDP alone. PLGA encapsulating hPNAS-4 combined with DDP may have promising applications in the therapy of ovarian cancer.