| The incidence and mortality of adenocarcinoma of the prostate continue to rise and will continue to pose a major public health problem.Prostate cancer is the second most common cause of cancer deaths on men.Despite progress in diagnosis and local therapy,fundmental questions remain with regard to the etiology, prevention,and treatment of prostate cancer.Our knowledge of prostate adenocarcinoma remains significantly less than of most other neoplasm.Finding a more sensitivity marker or oncogenic potential gene will provide us a useful tool to diagnose and cure prostate carcinoma.In the case of cancer, an abnormally increased cellular lifespan as a consequence of reduced apoptosis is ideal to favor the insurgence of genetid mutations,as well as to shield transformed cells from death induced by chemotherapy or radiotherapy,and to promote their survival at distant sites, Therefore,it is not surprising that manipulation of apoptosis has emerged as a new therapeutic strategy to help eliminate cancer cell. Survivin encode 142 amino acids, 16.5 KD intracellular protein that belongs to the inhibitor of apoptosis(IAP) gene family.Its chromosomal location is 17q25.Survivin is a bifunctional member of the inhibitor of apoptosis gene family that counteracts cell death and controls mitotic progression. Survivin possesses anti-apoptosis activity by binding and inhibiting the terminal effecter caspase 3 and 7.Survivin is expressed in the G2/M phase of the cell cycle and associates with microtubules of the mitotic spindle in a specific and saturable reaction that is regulated by microtubule dynamics.Survivin might participate in varios aspects of mitosis ,not only cytokinesis ,and might play a dominant role in microtubule function .Reminiscent of oncofetal antigens, surviving is present during embryonic development, is undetectable in most healthy adult tussues and becomes prominently overexpressed in nearly all-human cancers.Predictive and prognostic detection of surviving has been implemented in some types of cancer.Two general considerations make surviving an attractive therapeutic target in cancer: it is selectively expressed in tumor cells and it is required for their viability.Objective:1.To establish a novel ,safe and efficient prostate cancer gene therapy system; 2.To study the apoptosis of prostate cancer PC3,DU145,LNcap cells induced by survivin Survivin-D71A in vitro.3.To study the therapeutic effect of Survivin-D71A on solid prostate cancer in nude mice.Method:①To clone Survivin-D71A gene and construct recom- binant adenoviral shuttle vector pshuttle-Survivin-D71A.To acquire rebombinant adenoviral construct rAdeno-Survivin-D71A by homologous recombination with adenovirus bone plasmid pAdeasy-1 in BJ5183.To generate, amplification, condense and purify replication defective adenovirus Ad-Survivin-D71A by transfecting rAdeno- Survivin-D71A to QBI-293A.②To analyze the apoptotic effect of Ad-Survivin-D71A on prostate cancer cell lines with DAPI,flow cytometry and Western-blot.③Prostate cancer cells infected by Ad-Survivin-D71A were inoculated respectively in flank subcutaneous tissue of nude mice to establish xenograft models of human prostate cancer. The tumor growth status was observed and tumor volume was measured termly, and the tumor growth curve was drawn.Result :①The recombinant adenoviral shuttle vector pshuttle-Survivin-D71A containing the complete expre- ssion cassette was successfully constructed.After homologous recombination with pAdessy-1 in BJ5183, the recombinant adenoviral vector rAdeno- Survivin-D71A was successfully constructed. After package, amplification, condensation and purification, 1×1010pfu/mL recombinant adenovirus Ad-Survivin -D71A were generated for use.②DAPI staining showed that the apoptotic cells markedly in prostate cancer cells infected pAd-Survivin-D71A.The cell cycle analysis by flow cytometry showed that the G1 phase cells significantly incressed, S phase cells markedly decreased in prostate cancer cells infected pAd-Survivin -D71A.Western blot indicated that protein expression of surviving was also suppressed significantly in prostate cancer cells infected pAd-Survivin-D71A.③The tumorigenesis time delayed,tumor grew slow,tumor volume decressed significantly in Ad-Survivin-D71A group.Conclusion:1. Ad-Survivin-D71A might increase the apoptosis rate in prostate cancer cells. 2. Ad-Survivin-D71A can suppress significantly tumorigenesis and growth of human prostate cancer in nude mice. Survivin may act as a potential target for gene therapy of prostate cancer, meanwhile Ad-Survivin-D71A may provide a novel and important means for gene therapy of prostate cancer.
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