自噬基因Beclin1与上皮性卵巢癌发生、发展的相关性研究

Correlation of Autophagy Gene Beclin1 to Tumorigenesis and Development of Epithelial Ovarian Cancer

背景与目的:有研究表明自噬的抑制与肿瘤的发生有关,沉默自噬基因Beclin1可导致多种恶性肿瘤的发生。本研究探讨Beclin1基因在上皮性卵巢癌发生、发展中的作用,并分析其过表达对人卵巢癌细胞株SKOV3体外生长的影响。方法:用免疫组化检测25例正常卵巢组织、25例良性上皮性卵巢肿瘤、19例交界性上皮性卵巢肿瘤及69例上皮性卵巢癌组织的Beclin1表达;构建真核表达载体pcDNA3.1/Beclin1,脂质体法分别将质粒pcDNA3.1/Beclin1、pcDNA3.1转染人卵巢癌细胞株SKOV3,用MTT法分析外源性Beclin1过表达对SKOV3增殖的影响,并用流式细胞仪检测凋亡情况。结果:正常卵巢组织和良性卵巢肿瘤组织中Beclin1表达的积分光密度(integrated optical density,IOD)值均较高,两者之间的差异无显著性(P>0.05);交界性卵巢肿瘤组织中Beclin1的表达降低,而在上皮性卵巢癌中Beclin1表达的IOD值最低,与正常卵巢组织比较差异有显著性(P<0.05)。pcDNA3.1/Beclin1转染SKOV3细胞后细胞生长抑制率为(68.75±5.10)%,而pcDNA3.1转染组为(10.91±4.20)%,两者之间差异有显著性(P<0.05)。pcDNA3.1/Beclin1转染后72h SKOV3细胞的凋亡率为19.07%,高于pcDNA3.1转染组和未转染组,差异有显著性(P<0.05)。结论:Beclin1在上皮性卵巢癌中的表达下调,可能与上皮性卵巢癌的发生、发展有关;自噬基因Beclin1的过表达可抑制人卵巢癌细胞SKOV3的增殖,并诱导其凋亡。

BACKGROUND ＆ OBJECTIVE： Some studies have showed that autophagy suppression may result in malignant transformation, and the inactivation of autophagy gene Beclin1 induces malignancy. This study was to investigate the role of Beclin1 in the tumorigenesis and development of epithelial ovarian carcinoma, and to explore the effect of Beclin1 overexpression on the growth of ovarian carcinoma cell line SKOV3 in vitro. METHODS： The expression of Beclin1 in 25 specimens of normal ovarian tissue, 25 specimens of benign ovarian neoplasia, 19 specimens of borderline ovarian tissue, and 69 specimens of epithelial ovarian carcinoma was detected by immunohistochemistry. Eukaryotic expression vector pcDNA3.1/Beclin1 was constructed and transfected into SKOV3 cells; plasmid pcDNA3.1 was used as control. The effect of Beclin1 overexpression on the proliferation of SKOV3 cells was evaluated by MTT assay. Cell apoptosis was measured by flow cytometry （FCM）. RESULTS, The expression of Beclin1 was high in normal and benign ovarian neoplasia tissues, and there was no significant difference between the 2 groups （P〉 0.05）. Reduced Beclin1 expression was observed in borderline lesions, and the lowest level was detected in ovarian carcinoma tissues （P〈0.05）. The inhibition rate was significantly higher in pcDNA3.1/Beclin1-SKQV3 cells than in pcDNA3.1-SKOV3 cells [（68.75±5.10）% vs. （10.91±4.20）%, P〈0.05]. At 72 h after transfection, the apoptosis rate was significantly higher in pcDNA3.1/Beclin1-SKOV3 cells than in pcDNA3.1-SKOV3 cells and SKOV3 cells [（19.07±0.65）% vs. （4.30±0.50）% and （3.87±0.84）%, P〈0.051. CONCLUSIONS, Beclin1 expression is down-regulated in epithelial ovarian cancer tissues, which may relate to tumorigenesis and development of epithelial ovarian cancer. Beclin1 overexpression can inhibit proliferation and induce apoptosis of SKOV3 cells.