The Inhibit Effect And Mechanisms Of HDACi On The Proliferation And Apoptosis In Renal Cell Cancer

Part I The expression and potential application of histone deacetylase in renal cell carcinomaObjective:Enhanced actibity of histone deacetylases(HDAC) is associated with more aggressive tumour behavior and tumour progression in various solid tumours,the overexpression of these proteins and their functions in malignant neoplasms has led to the development of HDAC inhibitors(HDI).However,nothing is known about HDAC expression in clear-cell renal cell carcinoma(ccRcc) of our country,this research places emphasis on the HDAC expression of ccRCC our country and the activity,with the purpose of the reference for the isoform selective HDAC inhibitors.Methods:we investigated the expression of HDAC1,2and3and activity in36clear-cell renal cell carcinomas and corresponding normal renal tissue by the colorimetric Assay kit and western blot and correlated expression data with clinic-pathological parameters,we analyzed the difference of HDAC activity and expression between tumours and normal renal tissue.Results:we found the overexpression in the ccRCC of our country,the expression rate of HDAC1,2and3are86.1%,88.9%and66.7%respectively.meanwhile,the HDAC activity of the ccRCC is higher than the corresponding normal renal tissue,average81.9%,but it had not a significant correlation between the HDAC expression and age、grading、staging.Conclusion:Class I HDAC isoforms1,2and3are highly expressed in the ccRCC of our country,which suggests that HDAC inhibitors may be effective for the ccRCC of our country.Part II Effect of MS-275and TSA on the proliferation and apoptosis of renal cell carcinomaObjective:To investigate the effect of trichostatina A(TSA) and MS-275, histone deacetylase inhibitors,on the renal cell cancer cell line ACHN and to elucidate the role of inducing apoptosis and growth inhibition in RCC cells.Methods:The inhibitory dffects of TSA(0.05、0.1、0.2、0.4、0.8umol/1) and MS-275(0.05、0.1、0.2、0.4、0.8umol/1) at different time(24h、48h、72h) on cell growth inhibition were determined by MTT assay. Inverted phase contrast microscope was used to examine the morphological changes of cells.apoptosis of the ACHN was detected by flow cytometry assay. Western blotting was used to examine the Histone3acetylation.Results:The growth inhibition of TSA and MS-275were of time and dose dependent.the inhibitin rate of TSA and MS-275were51%and59.6%at the concertration of0.8umol/1and8umol/1and at the time of72h(p<0.05).the apoptosis rates of which were more significant(p<0.05). Results of inverted phase contrast microscope indicated apoptotic morphology such as shrinkage of anchorage cell,turned into small、round shape and began to shed off.Conclusion:MS-275and TSA can enhance the Histone3acetylation and inhibit ACHN cells growth in vitro and induce cell apotosis.