中文摘要：

目的通过RNA干扰技术抑制人胃癌细胞BGC823中人端粒保护蛋白（human protection of telomeresl，hPOTl）的表达，观察hPOTl RNA干扰对胃癌BGC823细胞突变型p53基因转录水平的影响。方法从hPOTl编码区外显子8的区域选取一段19个碱基的序列gtactagaagcctatctca为RNA干扰靶向序列，构建hPOTl的RNA干扰真核表达载体，转人体外培养的低分化人胃癌细胞BGC823，提取细胞总RNA，半定量RT-PCR检测hPOTl和突变型p53基因mRNA表达水平的改变，验证hPOTlRNA干扰载体的基因沉默效率，了解抑制hPOTl表达后突变型p53基因mRNA水平的改变。结果经DNA测序鉴定，hPOTlRNA干扰载体包含干扰序列的插入片段，插入位置正确。经半定量RT-PCR鉴定，RNA干扰组细胞的hPOTl mRNA表达水平明显下调，基因沉默效率在70％左右；突变型p53表达下调。结论通过RNA干扰技术抑制人胃癌细胞BGC823中hPOTl表达后，突变型p53表达下调，提示hPOTl与突变型p53之间有一定的相关性。

英文摘要：

Objective To inhibit the expression of human protection of telomeres 1 （ hPOT1 ） in gastric cancer cell BGC823 by RNA interference and to investigate the effect of hPOT1 on expression of mutant p53. Methods The 19 bases interference sequence targeting hPOT1 was selected from exon 8. RNA interference eukaryotic expression vector targeting hPOT1 was constructed and transfected into poorly differentiated human gastric cancer cell BGC823 in vitro. The expression of hPOT1 and mutant p53 in mRNA level were detected by semi-determination RT-PCR. Results RNA interference eukaryotic expression vector targeting hPOT1 was identified by DNA sequencing. The mRNA level of hPOT1 was inhibited significantly in cells of hPOT1 siRNA. The efficiency of gene silencing was about 70%. Decrase in mutant p53 expression was observed in cells of hPOT1 siRNA. Conclusion With the expression of hPOT1 in human gastric cancer cell BGC823 inhibited by RNA interference,the expression of mutant p53 decreased, indicating that hPOT1 correlate with mutant p53.