Effects of special AT-rich binding protein-1 overexpression on growth of implanted human prostate cancer LNCaP cell carcinoma in nude mice and possible mechanism

Objective To investigate the effects of overexpressed special AT- rich binding protein- 1 (SATB1)on the growth of implanted human prostate cancer LNCaP cell carcinoma in nude mice and possible mechanism. Methods The pcDNA3.1- SATB1, and pcDNA3.1 were transfected into human prostate cancer LNCaP cells by applying LipofectamineTM 2000. The xenografts prostate cell carcinoma cancer model was established by subcutaneously injecting 2×107 untransfected LNCaP, pcDNA3.1- SATB1 transfected LNCaP and pcDNA3.1 transfected LNCaP cells into the right flank of BALB/c nude mice. Immunohistochemistry and Western blotting were used to detect the expression of SATB1. The volume of tumor was firstly measured at the 7th day after the injection and then measured every four days.All mice were sacrificed at the 27th day. Td T- mediated d UTP nick end labeling(TUNEL) was used to assay the apoptosis of tumor cells in each group. Immunohistochemistry was used to detect the expression of Vimentin, E- cadherin and matrix metalloproteinase (MMP)- 2 in each group. Results Immunohistochemistry and Western blotting revealed in the pcDNA3.1- transfected group, SATB1 was stably expressed in nude mice, and tumor models of human prostate cancer LNCaP cells were constructed successfully.Final volume(mm3) of tumor in pcDNA3.1- transfected LNCaP cells group was 2 242.0±259.2, significantly greater than in control groups(P<0.05).TUNEL assay showed the average rate of apoptosis in the pcDNA3.1- transfected group was(31.3±8.9)%, significantly higher than in the control groups(P< 0.05). The average IOD values of Vimentin, MMP- 2 and E- cadherin expression in the pcDNA3.1- transfected group was 417.9±18.2, 539.1±41.6, and 156.4±11.9, and there were statistically significant difference in comparison with the control group(P< 0.05). Conclusion The tumor models of human prostate cancer LNCaP cells overexpressing SATB1 gene were successfully constructed. SATB1 can promote the growth and proliferation, and inhibit apoptosis of prostate cancer cells probably by regulating E- cadherin, Vimentin, and MMP- 2, which provides the basis for research on the metastasis mechanism of prostate cancer. Key words: Special AT-rich binding protein-1; Prostate cancer; Model,animal