中文摘要：

目的探讨MCPHl基因在肺癌组织和正常组织的蛋白表达分布及其过表达后对人肺腺癌细胞系H1299凋亡的影响。方法临床收集20例肺癌组织和8例正常肺组织标本，免疫组化法检测MCPHl蛋白在肺组织的表达分布，真核表达质粒pcDNA3．1（-）／MCPHl和空白质粒pcDNA3．1瞬时转染肺癌细胞株H1299，并设立未处理组。转染质粒48h后，采用ReM．timePCR法检测细胞中MCPHl基因mRNA的转录表达情况；转染72h后提取细胞总蛋白，Westernblot检测细胞中MCPHl蛋白表达水平，流式细胞术检测细胞凋亡。结果MCPHl蛋白在肺癌组织中表达低于正常组织，而且MCPHl蛋白在癌组织中表现为核质低表达，在正常组织中为核质高表达；H1299转染pcDNA3．1（-）／MCPHl重组质粒后，可有效上调H1299细胞中MCPHl基因的mRNA和蛋白表达，处理组的细胞凋亡率（18．10±1．87）％较pcDNA3．1（-）转染组（5．76±1．85）％和未处理组（5．85±0．57）％显著增加（P〈0．05）。结论MCPHl在人肺癌组织表达降低，过表达之后可诱导肺腺癌细胞发生凋亡。

英文摘要：

Objective To evaluate the expression of protein microcephalin （ MCPH1, also known as BRCT-repeat inhibitor of hTERT expression, BRIT1 ） in lung tissues and investigate the effects of its over-expression on the apoptosis of human lung cancer cell line H1299. Methods The protein expression of MCPH1 in 20 tissue samples of lung cancer and 8 samples of normal lung tissues were studied by immuno-histochemistry. Eukaryotic expression plasmid pcDNA3. 1 （ - ）/MCPH1 and blank plasmid pcDNA3. 1 were transferred to lung cancer ceils H1299, and the ceils without transfection served as control. In 48 h after transfection, the cells were detected for transcription and expression of MCPH1 mRNA by real-time PCR. In 72 h after transfection, the total protein was extracted and the MCPH1 protein were determined by Western blotting. The apoptosis of H1299 cells was determined by flow cytometry. Results The expression of MCPH1 occurred mainly in the nucleus of normal tissues and was much lower in lung cancer tissues than in normal tissues. Both the expression of MCPH1 mRNA and protein were up-regulated effectively in H1299 cells after transfection with plasmid pcDNA3.1 （ - ）/MCPH1. The apoptotic rate of H1299 cells transfected with plasmid pcDNA3.1 （ - ）/MCPH1 was significantly higher than those transfected with the blank pIasmid and those untransfected [ （18.10 ± 1.87）% vs （5.76 ± 1.85）% and （5.85 ± 0.57）%, P〈0. 05]. Conclusion MCPH1 protein is expressed in the cytoplasm of lung cancer tissues with lower expression. Over-expression of MCPH1 significantly induces the apoptosis of human lung cancer cells in vitro.