Inhibitory effect of oncolytic adenovirus ZD55-special AT rich sequence binding protein 1 on proliferation and invasion of andragon-independent prostate cancer DU145 cells

Abstract

Objective To investigate the suppressive effect of oncolytic adenovirus ZD55-special AT rich sequence binding protein 1 (SATB1) expressing small hairpin RNA targeting SATB1 gene on growth and invasion of prostate cancer DU145 cells. Methods The oncolytic adenovirus ZD55-SATB1 was constructed and identifies. The inhibitory effect of ZD55-SATB1 on SATB1 expression was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting analysis at 72 h after infection of DU145 cells with ZD55-SATB1 at a MOI of 10. The cytotoxicity of ZD55-SATB1 was detected by cell counting kit-8 (CCK-8) assay and crystal violet staining assay. Cell invasion was detected by Matrigel invasion assay. The expression of E1A protein in DU145 cell lines infected with viruses respectively was detected by Western blotting. Results The oncolytic adenoviruses ZD55-SATB1 were successfully constructed and identified. RT-PCR and Western blotting assay showed that ZD55-SATB1 could significantly decrease the expression of SATB1 in DU145 cells (P<0.05). The relative protein levels of E1A in DU145 cells treated with ZD55-SATB1 were significantly higher than those in human normal prostate epithelial cell line PZ-HPV-7 cells (P<0.01), which indicated cancer specificity of ZD55-SATB1 for prostate cance cells. Crystal violet staining assay showed that ZD55-SATB1 exhibited obvious cytotoxicity in DU145 cells. The cytopathic effect of ZD55-SATB1 was much stronger than that of ZD55-enhanced green fluorescent protein (EGFP) and Ad-SATB1. CCK-8 assay showed that cell viability of ZD55-SATB1 group [(31.60±3.31)%] was significantly lower than that in ZD55-EGFP group [(61.70±2.42)%, P=0.025] and Ad-SATB1 group [(82.40±3.54)%, P=0.017] for DU145 cells after 4 days. Transwell cell invasive experiment showed that the number of cells that invaded the membrane in ZD55-SATB1 group was (61.30±17.25) cells, significantly less than that in the Ad-SATB1 group [(170.10±25.44) cells, P=0.043], the ZD55-EGFP group [(295.40±23.36) cells, P=0.013] and the PBS group [(490.50±33.36) cells, P=0.009]. Conclusion Oncolytic adenovirus ZD55-SATB1 could effectively knockdown the SATB1 expression in DU145 cells, and dramatically inhibit proliferation and invasion of DU145 cells. Key words: Oncolytic adenovirus; Special AT rich sequence binding protein 1; Proliferation; Invasion