Objective: To explore the transgenic efficiency of non-viral vector Tf-PEG-PEI and the cell specific silencing effect of plasmid pPSMAe/p-shNS-ploy(A) on prostate cancer cells.
Methods: Polyethyleneimine (PEI) was modified by using polyethylene glycol and transferrin to synthesize the non-viral vector Tf-PEG-PEI. NS-specific plasmids pPSMAe/p-shNS-ploy(A) and Tf-PEG-PEI were used to transfect prostate cancer LNCap and PC-3 cells. The changes of cell morphology, proliferation ability and cell cycle were studied after down-regulating the NS gene level.
Results: Tf-PEG-PEI was successfully modified. After transfection, the PSMA-expressing LNCaP cells became larger and showed more pseudopodia, having a tendency to differentiate. Their cell proliferation ability was reduced, and the detection of cell cycle showed a decrease of S phase and an increase of G(1) phase after knocking down NS gene. These targets were not changed in non-PSMA-expresing PC-3 cells.
Conclusions: The non-viral vector Tf-PEG-PEI has a high ability to transfer targeted gene into target cells. The cellular specificity of short-hairpin RNA transcription driven by PSMAe/p is confirmed by silencing NS gene. The use of cell specific promoter may be an effective strategy of gene therapy for prostate cancer.