卵巢癌组织Hippo-Yes相关蛋白表达与临床病理参数及增殖凋亡相关性研究

Clinicopathological significance of YAP and its correlation with proliferation and apoptosis in ovarian carcinoma tissues

目的探讨卵巢癌组织中Hippo-Yes相关蛋白(Yes-associated protein,YAP)的表达与临床病理参数的关系,及其对卵巢癌细胞增殖和凋亡的影响。方法免疫组化染色技术检测湖南省肿瘤医院病理科2010-01-01-2013-12-31保存的68例卵巢癌及38例良性卵巢组织中YAP蛋白表达,分析YAP表达与卵巢癌临床病理参数的相关性;逆转录病毒介导的YAP shRNA干扰人卵巢癌EFO-21细胞中YAP表达,蛋白质印迹法检测干扰效率,5-溴脱氧尿嘧啶核苷(5-Bromo-2-deoxy Uridine,BrdU)细胞增殖分析和流式细胞术检测肿瘤细胞增殖和凋亡变化。结果卵巢癌组织YAP蛋白阳性表达率为61.8%(42/68),良性卵巢组织为10.5%(4/38),差异有统计学意义,χ2=26.054,P<0.001。卵巢癌组织中YAP蛋白阳性表达率在高临床分期(χ2=8.600,P=0.003)和高病理分级(χ2=5.688,P=0.017)中显著升高。YAP shRNA显著降低卵巢癌EFO-21细胞中YAP蛋白表达,对照组YAP蛋白表达为0.96±0.16,实验组为0.14±0.04,P<0.001。YAP shRNA导致肿瘤细胞增殖能力显著减弱,对照组细胞增殖水平为121.00±3.19,实验组为55.83±3.56,P<0.001。YAP shRNA并诱导细胞凋亡,对照组凋亡率为(8.75±0.15)%,实验组为(32.75±4.76)%,P<0.001。结论 YAP蛋白在卵巢癌组织中表达异常升高并核内蓄积,其阳性表达与高病理分级和高临床分期显著有关,干扰YAP表达导致肿瘤细胞增殖减弱和凋亡增加,提示YAP通过促进肿瘤细胞生长发挥促癌作用,其可能成为卵巢癌靶向治疗的潜在靶点。

OBJECTIVE To investigate the expression of Yes-associated protein （YAP） in ovarian cancer tissues and its effects on cell proliferation and apoptosis in ovarian cancer cells. METHODS We detected YAP expression in 68 samples of paraffin-embedded ovarian cancer and 38 samples of normal ovarian tissues, which were stored in Depart- ment of Pathology, Tumor Hospital of Hunan Province during 1st Jan. 2010 to 31th Dec. 2013, using immunohistochem- istry and analyzed the clinicalpathological significance of YAP in ovarian carcinoma. Silence of YAP by retrovirus-media- ted YAP shRNA in EFO-21 cells was confirmed by Western blot. The cell proliferation and apoptosis were analyzed using 5-Bromo-2-deoxy Uridine （BrdU） cell proliferation assay and flow cytometry. RESULTS The positive expression rates of YAP in ovarian cancer tissues and normal ovarian tissues were 61. 8% （42/68） and 10. 5% （4/38）, respectively. The difference was statistically significant （X^2 = 26. 054, P〈0. 001）. The positive expression rate of YAP was significantly higher in advanced clinical stage （X^2 = 8. 600, P = 0. 003） and high histological grading （X^2=5. 688, P = 0. 017 ）. Specific shRNA significantly decreased the protein level of YAP in EFO-21 cells （control group： 0. 96 ±0. 16 vs experimental group： 0.14±0. 04,P〈0. 001）, YAP knockdown decreased cell proliferation （control group： 121.00±3. 19 vs experi- mental group ： 55.83 ± 3. 56, P 〈 0.001 ） and induced cell apoptosis [ control group ： （8.75 ± 0.15 ） % vs experimental group： （32.75±4.76） %, P〈0. 001] in EFO-21 cells. CONCLUSIONS The elevated expression and nuclear accumulation of YAP is observed in ovarian cancer tissues, its high-expression is associated with high histological grading and advanced clinical stage. YAP knockdown lead to decreased proliferation and increased apoptosis in EFO-21 cells, suggesting that YAP acts as an oncogene by promoting tumor cell growth and may be a potential therapeutic target for ovarian cancer.