卵巢肿瘤组织中端粒酶活性的表达

Expression of telomerase activity in ovarian neoplasmas

目的分析端粒酶活性在卵巢肿瘤中的表达,探讨端粒酶活性作为卵巢肿瘤诊断肿瘤标记物的意义。方法取冰冻肿瘤组织,采用端粒重复序列扩增法(Telomeric Repeat Amplication Protocol),结合银染,共测定了27例卵巢癌、5例良性卵巢肿瘤、22例卵巢癌癌旁组织以及12例正常卵巢组织中端粒酶活性,并分析其与组织分级、FIGO分期、病理类型以及有无转移的关系。PCR产物以采用聚丙烯酰胺凝胶电泳分析,以出现特征性的6-bp间隔的特征性阶梯状条带为阳性。出现>100bp的条带为强阳性,出现<99bp的条带为中低阳性。结果本实验共对66份标本进行了检测,12例正常卵巢组织中,仅有2例表达端粒酶活性;5例卵巢良性肿瘤中,1例表达端粒酶弱阳性。27例卵巢恶性肿瘤标本中,有23例表达端粒酶活性(其中强阳性16例);在检测的22例卵巢上皮癌的癌旁组织中,有12例表达端粒酶弱阳性。卵巢恶性肿瘤的端粒酶活性表达阳性率显著高于卵巢良性肿瘤(P=0.0090)和正常卵巢(P=0.0000)。Ⅰ-Ⅱ期患者端粒酶活性阳性率71%,Ⅲ-Ⅳ期患者端粒酶活性阳性率90%(P=0.269)。而强阳性率Ⅲ-Ⅳ期明显高于Ⅰ-Ⅱ期(P=0.009)。在肿瘤类型和组织学分级中,端粒酶阳性表达率均没有显著差异。结论在卵巢恶性肿瘤组织中端粒酶活性有较高的表达率;早期和晚期卵巢肿瘤组织中端粒酶活性阳性率没有明显差异,但晚期卵巢肿瘤组织中的端粒酶活性程度较高;端粒酶活性有可能作为早期诊断卵巢肿瘤的标记物之一,并可以作为卵巢肿瘤判断预后的指标。

Objective：The purpose of the study was to evaluate the levels of telomerase activity in ovarian neoplasmas,analysis the signification of telomerase activity as a tumor marker in early diagnosis of ovarian neoplasmas.Methods： In the present study,telomerase activity was examined in frozen tissue specimens of malignant ovary tumor（n=27）,benign ovarian tumor（n=5）,normal tissue of malignant ovarian tumor（n=22） and normal ovary tissue（n=12）.The relationship was analyzed between telomerase activity and clinic-pathological parameters such as histological grade,FIGO stage,presence of distant metastasis at diagnosis of ovarian maliganant tumor.Telomerase activity was assessed by the telomeric repeat amplification protocol（TRAP）.The PCR products were analyzed by electrophoresis and silver dyeing protocol.Evidence of a 6-bp telomeric repeat ladder indicates presence of telomerase activity.The high or moderate telomerase activity was assigned to its ability to synthesize the length of DNA ladders in TRAP assay.The ladders100bp were graded as high level.The ladders≤99bp were graded moderate level of telomerase activity.Results： Total 66 samples ware tested.Telomarase activity could be detected in the 2 of 12 normal ovarian tissues,1 of 5 ovarian benign tumors,23 of 27 malignant ovarian tumors,and 12 of 22 proximal tissues.The telomrase activity rate of malignant ovarian tumors were higher than that of benign tumor and normal tissues（P=0.0090 and 0.0000 respectively）.The telomrase activity rates were 71% and 90% in early and later stage respectively（P=0.269）.But the higher level of telomerase activity can be detected in terminal stage of ovarian neoplasmas（P〈0.05）.There were no significant differences between tumor types and histological classification.Conclusions： This study shows a high expression rate of telomerase activity in malignant ovarian tumor.There is no significant difference between early stage ovarian neoplasmas and terminal stage.But the higher level of telomerase activity can be detected in terminal stage of ovarian neoplasmas.Telomerase activity may be a useful marker in diagnosis of ovarian neoplasmas,and be a prognostic indicator of outcome.