Study On The Effect Of HDAC1 Gene Targeting SiRNA On Gastric Carcinoma

【Objective】To investigate the expression of HDAC1 and histone H3,H4 acetylation in gastric cancer tissue,we design a siRNA segments targeting HDAC1 gene to study the effect on cells growth,cells apoptosis and histone modification in gastric cancer MGC-803 cells line.【Methods】1. The expression of HDAC1,histone acetylation of H3,H4 was detected by immunohistochemical method in gastric cancer , chronic superficial gastritis, atrophic gastritis and mediate to severe dysplasia. 2. Four siRNA segments targeting HDAC1 gene were design. Transfection into MGC-803 cells was performed by Lipofectamine 2000. The optimal segment was screened by RT-PCR and Western blot. 3. Cell growth affected by HDAC1 siRNA was determined by MTT. Cell apoptosis was measured by TUNEL assay. 4. The expression of BCL-2,Caspase-9,Caspase-3,P21 and C-myc and the expression of histone acetylation of H3, H4 and histone methylation of H3K9 were detected by Western blot.【Result】1. The expression of HDAC1 in gastric cancer is 73.71%,which is significantly higher than that in other benign of gastric disorders(p<0.05). It is correlated with degree of differenciation, depth of infiltration, lymphatic metastasis and TNM stag in gastric cancer compared to other benigh gastric disorders(p<0.05). The expression rate of histone acetylation of H3 in gastric cancer is 41.17%,which is lower than that in others(p<0.05). It is correlated with differenciation and lymphatic metastasis in gastric cancer compared to others(p<0.05).2. The optimal segment is screened from four siRNA segments design for HDAC1. The sequence is sense 5'-CCCGGAGGAAAGUCUGUUATT-3 , antisense 5- UAACAGACUUUCCUCCGGGTG-3'.3. HDAC1 siRNA upregulates P21 and surpresses the proliferation of MGC-803 cells. It decreases BCL-2,Caspase-9,Caspase-3,C-myc and induces cells apoptosis. 4. HDAC1 siRNA upregulates histone acetylation of H3, H4 and downregulates histone methylated H3K9.【Conclusion】1. The higher expression of HDAC1 and lower expression of histone acetylation of H3 in gastric cancer tissue are related to pathological differenciation and lymphatic matastasis. It suggests that HDAC1 play an important role in cancer generation , development , infiltration and matastasis of gastric cancer.2. HDAC1 siRNA inhibits cell proliferation inMGC-803 cells and induces cell apoptosis. It upregulates histone acetylation of H3 , H4 and downregulates methylated H3K9,It might be a new therapeutic target in gastric cancer.Its mechanism need to be further studied.