肾癌组织的端粒酶活性

目的探讨端粒酶活性与肾细胞癌之间的关系。方法采用改良ＴＲＡＰ法对３２例肾细胞癌组织及正常肾组织和可疑癌旁组织中端粒酶活性进行检测,同时了解其与临床生物学特征的关系。结果３２例肾细胞癌组织中端粒酶强阳性１７例,阳性１２例,阴性３例,阳性率９１％;３２例正常肾组织中端粒酶弱阳性者仅２例,阳性率６％;可疑癌旁组织阳性者６例,阳性率１９％。三组端粒酶活性比较,阳性率差异有显著性（Ｐ＜０．０１）。结论肾细胞癌组织中端粒酶活性检出率高,特异性强,无假阳性和假阴性。提示端粒酶活性检测可作为判断肾肿瘤恶性程度的标记物,并可能成为判断肾肿瘤预后的一项指标。     

膀胱癌癌旁组织端粒酶活性检测的临床意义

目的　探讨膀胱癌癌旁组织端粒酶活性检测的临床意义。　方法　采用端粒重复序列扩增 (TRAP)法 ,检测 2 4例膀胱癌组织及癌旁组织中端粒酶活性表达。　结果　 2 4例癌旁组织中端粒酶活性表达阳性 10例 (42 % ) ,癌旁组织端粒酶活性表达与原发灶癌病理分级分期相关 ,并与癌复发相关。　结论　膀胱癌癌旁组织端粒酶活性检测可作为判断膀胱癌预后的指标之一     

胰腺癌组织中端粒酶活性的表达

目的　探讨端粒酶活性与胰腺癌之间的关系 ,评价其作为胰腺癌诊断新的肿瘤标志物的可能性。方法　采用重复片段扩增SYBRGreen染色法 ,对 42例胰腺癌癌患者癌组织及其癌旁组织的端粒酶活性进行检测。结果　胰腺癌组织中端粒酶阳性率为 80 .9% (3 4/4 2 ) ,而在癌旁组织中仅 7.1% (3 /4 2 )表达端粒酶活性 ,胰腺癌组织端粒酶活性显著高于癌旁组织 (P <0 .0 0 1)。端粒酶活性的表达与胰腺癌组织的肿瘤大小、淋巴结转移、病理学临床分期及分化程度相关。结论端粒酶活性是特异性较强的恶性肿瘤分子标志物 ,其检测有可能成为胰腺癌诊断和预后判断的有效指标     

前列腺衰老逃逸现象的实验研究

目的探讨良性前列腺增生(BPH)衰老逃逸现象的机理。方法采用端粒重复片段扩增法(TRAP)分别检测13例正常前列腺组织、35例BPH组织及33例增生结节和包膜的端粒酶活性表达情况,比较端粒酶活性水平与BPH衰老逃逸的关系。结果正常前列腺组织中端粒酶阳性2例(15%),BPH组织中端粒酶阳性17例(49%),增生结节端粒酶阳性14例(42%),包膜阳性1例(3%);BPH组织端粒酶阳性表达率高于正常前列腺组织(P<0.05),增生结节阳性率明显高于包膜组织(P<0.01)。结论BPH组织中端粒酶活性升高,且分布不均匀。提示前列腺衰老逃逸可能与端粒酶活性有关。     

肝癌细胞中端粒酶逆转录酶与c-myc表达的关系

目的探讨肝细胞肝癌（HCC）中端粒酶逆转录酶（hTERT）与C—myc蛋白表达情况及其相关性。方法采用免疫组化SP法检测52例HCC癌组织及相应癌旁组织中hTERT与c—myc蛋白表达,并用TRAP—ELISA法检测上述组织中的端粒酶活性。结果HCC组织中hTERT与C—myc蛋白阳性率分别为86．5％（45／52）和78．8％（41／52）,它们与相应癌旁组织比较差异有统计学意义（P〈0．01）;HCC癌组织中端粒酶活性阳性率为80．8％（42／52）,明显高于相应癌旁组织（15．4％,8／52）;HCC癌组织中端粒酶活性、hTERT及C—myc蛋白阳性表达率两两均呈显著正相关（r=0．761,P〈0．001;r=0．654,P〈0．001;r=0．486,P〈0．001）。结论HCC癌组织中hTERT与C—myc蛋白过度表达,两者相互作用而共同参与肝癌端粒酶活性的调控。     

膀胱癌组织端粒酶活性的研究

目的　探讨膀胱癌组织端粒酶活性的临床意义。　方法　应用银染端粒重复序列扩增法检测 42例膀胱癌及其癌旁组织的端粒酶活性。　结果　 3例正常膀胱组织端粒酶表达均阴性 ;42例膀胱癌组织中端粒酶表达阳性 35例 (83 .3 % ) ,癌旁组织端粒酶表达阳性 7例 (16 .7% ) ;浸润癌或有淋巴结或远处转移者端粒酶表达阳性率高于非浸润癌或无转移者 ,但差别无显著性意义 (P >0 .0 5 )。　结论　端粒酶是膀胱癌较理想的肿瘤标记物之一。     

胃癌组织和外周血中端粒酶活性的研究

目的测定端粒酶在胃癌患者的肿瘤组织、外周血中的活性，以探讨端粒酶活性的表达及其在临床应用上的意义。方法应用TRAP—PCR—ELISA方法检测36例胃癌患者的癌组织及其相应癌旁组织、正常组织、外周血单核细胞中端粒酶活性以及20例正常对照者外周血单核细胞端粒酶的活性。结果癌组织、癌旁组织、正常组织中端粒酶阳性率分别为80．6％（29／36）、16．7％（6／36）和5．6％（2／36）。6例胃癌患者外周血有18例测到端粒酶阳性，阳性率为50％，正常人外周血未测到端粒酶阳性。癌组织与癌旁组织及正常组织之间、胃癌患者外周血与与正常人外周血之间的端粒酶阳性率差异有统计学意义（P〈0．01）。端粒酶活性与患者的性别、年龄、肿瘤大小、浸润深度、分化程度、淋巴转移和TNM分期等临床病理参数差异无统计学意义（P〈0．05）。结论检测患者胃癌组织、外周血中端粒酶活性有助于胃癌的早期诊断，对预后监控及治疗也有重要意义。     

TRAP-Sybr Green I法检测结直肠癌端粒酶活性

目的应用新型核酸荧光染料Sybr Green Ⅰ检测端粒酶活性，并探讨该酶活性在结直肠癌临床诊断中的意义。方法用端粒重复扩增(TRAP)结合Sybr Green Ⅰ技术检测46例结直肠癌及19例癌旁组织中端粒酶的活性。结果Sybr Green Ⅰ能清晰显示端粒酶扩增后的条带。端粒酶活性在结直肠癌中阳性率为89．13％，在癌旁组织中未发现端粒酶活性。端粒酶活性与细胞分化程度、Dukes分期、有无淋巴结转移均无关。结论用Sybr Green Ⅰ检测端粒酶活性对于诊断结直肠癌具有重要的临床辅助价值。     

大肠癌端粒酶各组分表达及其与端粒酶活性的关系

目的：研究端粒酶的3种组分与其活性的关系,探讨端粒酶激活的关键因素。方法：采用TRAP法检测大肠癌组织及相邻正常黏膜组织中端粒酶活性,用RT－PCR检测端粒酶3种组分的表达。结果：在64例（85．33％）癌组织中检测到端粒酶活性,正常黏膜中没有端粒酶活性,两者差异有显著性（P＜0．01）;hTR和TP1基因的表达在癌组织和正常黏膜没有差别,hTERT在癌组织中的表达要明显高于正常黏膜,差别具有显著性（P＜0．01）,hTERT基因表达强度与端粒酶活性密切相关。结论：大肠癌端粒酶活性表达具有肿瘤特异性,hTERT在癌组织中的表达明显高于正常粘膜,大肠癌中端粒酶活性和hTERT基因表达强度密切相关,hTERT基因表达可能是端粒酶激活的关键因素。     

Twist、E-钙粘蛋白在肾癌转移进展中的意义

目的探讨Twist蛋白和E-钙粘蛋白在人肾细胞癌(renal cell carcinoma,RCC)组织中的表达及其相关性。方法应用免疫组织化学SABC染色方法检测40例RCC及癌旁正常组织中Twist蛋白、E-钙粘蛋白的表达情况,分析二者相关性。结果 RCC组织中Twist蛋白的阳性表达率(87.5%)明显高于癌旁肾组织中Twist蛋白的阳性表达率(32.5%);RCC组织中E-钙粘蛋白的阳性表达率(12.5%)明显低于其在癌旁肾组织中的阳性表达率(95.0%),Twist蛋白和E-钙粘蛋白表达在肾癌组织和癌旁组织中的差异均有统计学意义(P<0.01)。其中Twist的异常表达与RCC病理分级、临床分期、淋巴结转移呈正相关(P<0.05),E-钙粘蛋白的异常表达与RCC病理分级、临床分期、淋巴结转移呈负相关(P<0.05),而两者与患者的性别、肿瘤直径、年龄无相关性(P>0.05)。结论 Twist蛋白可能是RCC发生、发展及浸润转移的重要因素之一。     

Telomerase activity in human renal cell carcinoma

OBJECTIVE: To determine if telomerase activity plays an important role in the progression of renal cell carcinoma (RCC). MATERIALS AND METHODS: Telomerase activity was measured in 53 tissue samples of RCC (52 patients), 11 samples of normal renal tissue and six tissue samples from benign renal disease using a fluorescence-based telomeric repeat amplification protocol. The activity was assessed for associations with clinical and pathological variables of RCC. To examine the influence of telomerase activity on cell immortalization in vitro, primary cultures of RCC cells were produced; the maximum passage number beyond which cell culture could not be continued was compared with the associated telomerase activity. RESULTS: Among the tissue samples of benign renal disease, one from a patient with a hydronephrotic nonfunctioning kidney had detectable telomerase activity, whereas none of the normal renal tissues had. In 32 of the 53 RCC tissue samples (60%), telomerase activity was detectable, varying from 1.8 to 100.0 TPG units, but was not associated with any clinical or pathological variable such as clinical stage, tumour size, grade or pathological subtype. Telomerase activity also had no association with the maximum passage number of primary cell cultures. CONCLUSIONS: Telomerase activity may not be a prognostic marker for RCC. Alternative mechanism(s) which lengthen telomeres should be considered if maintaining telomere length is considered essential to tumour progression.     

Telomerase activity in human renal cell carcinoma

PURPOSE: Telomerase activity has been detected in a wide variety of human tumors. The present study evaluated telomerase activity in association with the acquisition of renal cell carcinoma (RCC). METHODS: Telomerase activity was examined in 30 RCC and the adjacent normal kidney tissue, obtained as surgical specimens. The activity was assayed by polymerase chain reaction-based telomeric repeat amplification protocol assay. RESULTS: Among the 30 RCC, 18 (60%) displayed telomerase activity, whereas none of the normal tissue samples exhibited it. Subdivision of the tumors according to telomerase activity did not reveal any obvious difference in distribution with regard to tumor size, stage, histocytological subtype, or DNA-ploidy. However, a statistically significant relationship was found between the frequency of telomerase-positive activity and both serum immunosuppressive acidic protein level in the patient and tumor grade (P<0.05). There was no significant difference in the recurrent-free survival and the disease-specific survival between patients with positive telomerase activity and patients with negative activity. CONCLUSION: The present results indicate that telomerase activity might be related to the progression of RCC and thus a marker of malignant potential.     

前列腺穿刺活检组织端粒酶活性检测及其临床意义

通过检测国人前列腺穿刺活检组织端粒酶活性,探讨其在前列腺癌诊断和预后的临床意义。20例前列腺癌标本和16例癌旁组织均来自前列腺穿刺活检,14例良性前列腺增生(BPH)标本取自前列腺摘除手术,均经病理证实。采用改良的TRAP-银染方法检测端粒酶活性,并进行半定量分析。结果20份前列腺癌标本中18份测得端粒酶活性(90％)。在16例癌旁前列腺组织中,64％(7/11)的前列腺上皮肉瘤(PIN)及40％(2/5)的癌旁BPH组织有端粒酶活性表达。14例BPH标本端粒酶活性均为阴性。18例前列腺癌阳性标本的端粒酶活性强度与肿瘤分级分期及PSA水平呈正相关。前列腺穿刺活检组织端粒酶活性检测可作为前列腺癌诊断的一项敏感性指标,其在前列腺癌预后中的价值有待于进一步的研究。     

Renal cell carcinoma (RCC) and telomerase activity: relationship to stage

Limited information is available on the correlation of telomerase activity and the clinical and pathological characteristics, in patients with renal cell carcinoma (RCC). Telomerase repeat amplification protocol (TRAP) was used to measure telomerase activity in frozen RCC specimens from partial/radical nephrectomies performed between 1987 and 1991. Presence of tumor tissue was verified by a pathologist using hematoxylin and eosin stained sections. RNA was measured to ensure the presence of intact protein necessary for telomerase expression. Data on demographics, tumor type, and stage at presentation, local recurrence, distant metastasis, disease-free survival (DFS), and overall survival (OS) was collected, and telomerase activity was correlated with each of these variables. Forty-nine of 67 patients (73%) were telomerase positive (+ve). Gender and stage were the only variables that appeared to be associated with telomerase positivity. Tumors were telomerase +ve in 12/21 females (57 %) vs. 37/46 males (80%) (P = 0.07). Tumors were telomerase +ve in 85% of Stage IV, 76% of Stage III, and 70% of Stage I/II patients (P = 0.12). Five-year survival was 0% for Stage IV, 57% for Stage III, and 77% for Stage I/II patients (P < 0.001), DFS 54% for stage III and 84% for Stage I/II patients (P = 0.05). Telomerase activity, however, was not related to survival in either univariate or multivariate analysis. In patients with telomerase +ve tumors 5-year survival was 55%, and with telomerase −ve tumors 58% (P = 0.56). Stage was the only variable associated with OS or DFS in clear cell RCC patients. In patients with advanced disease, there is a high incidence of telomerase positivity was found, within this limited sample, however, no correlation with survival was found.     

Telomerase activity in malignant and benign renal tumors

OBJECTIVES: An important characteristic of malignant cells is their unlimited replicative potential, their immortality. In conferring this immortality, the enzyme telomerase is believed to play a crucial role. The detection of telomerase activity provides new knowledge regarding the biologic growth behavior of tumors and offers new diagnostic and therapeutic tools. METHODS: In the present study the sensitive TRAP assay (telomeric repeat amplification protocol) was used to examine 44 malignant renal tumors and 8 benign tumors of the kidney and 52 specimens of normal renal tissue for telomerase activity. RESULTS: Telomerase activity was detected in 63% of tissue samples obtained from histologically confirmed renal cell carcinomas. In cases of renal cell carcinoma restricted to the kidney, telomerase activity was detected in 58%. In cases in which tumor growth has progressed beyond the limits of the organ, telomerase activity was found in 69%. This stage dependence, however, did not reach statistical significance. No correlation to tumor grading was observed. Telomerase activity was found less frequent in chromophobe renal cell carcinomas. Neither the 8 benign renal tumors (4 oncocytomas and 4 angiomyolipomas) nor the specimens of normal kidney showed any evidence of telomerase activity. CONCLUSIONS: The proportion of remarkable slow-growing renal cell carcinomas showing telomerase activity is less than in other malignancies and may correlate with biologic growth behavior. Possible explanations include the presence of an alternative pathway, called ALT (alternative lengthening of telomeres) and an association with the loss or presence of the telomerase suppressor on the short arm of chromosome 3. Prolonged follow-up will be of special interest to determine whether lack of telomerase activity predicts favorable outcome.     

Telomerase activity in renal cell carcinoma by modified telomeric repeat amplification protocol assay

BACKGROUND: Previous assessments by the conventional telomeric repeat amplification protocol have not been reliable for the quantitation of telomerase activity. We, therefore, determined telomerase activity in renal cell carcinoma (RCC) tissue by the modified sensitive telomeric repeat amplification protocol assay. METHODS: Telomerase activity was examined in 23 cases of RCC and in the adjacent normal kidney tissue, and assessed for associations with clinical and pathological variables of the disease. RESULTS: The linearity and quantitation of the modified method was confirmed. Mean telomerase activity of RCC (1987.889 +/- 1232.801 units) was significantly greater than that of normal renal tissue (173.467 +/- 241.893 units) (P = 0.0001). Telomerase activity in RCC was, however, not associated with clinical or pathological variables such as clinical stage (P = 0.8941), grade (P = 0.8043) or pathological subtype (P = 0.9739). CONCLUSION: The results suggest that telomerase might play a crucial role in an initial step of the development of RCC, but not in the progression of the disease.     

Telomerase activity as a predictive marker for recurrence of hepatocellular carcinoma after hepatectomy

BACKGROUND: Expression of telomerase activity and stabilization of telomeres are concomitant with attainment of immortality in tumor cells. Telomerase activity levels in hepatocellular carcinoma (HCC) may serve as a predictive marker for recurrence after surgery. METHODS: Telomerase activity levels in HCC were measured in 37 patients undergoing hepatectomy by the telomeric repeat amplification protocol. The clinicopathologic factors and telomerase activity were analyzed to identify factors that were important in affecting recurrence of HCC and recurrence-free survival. RESULTS: Telomerase activity was detected in 23 patients (62.2%), and was not significantly associated with seven other HCC-related factors. After a median follow-up of 34 months, 24 patients (64.9%) had recurrence of HCC. In univariate analyses, telomerase activity of more than 20 total product generated (TPG) and portal vein invasion were found to be significantly related to a shorter time to recurrence. Multivariate analysis demonstrated that telomerase activity (>20 TPG) was significantly related to an increased risk of recurrence (relative risk 2.36, 95% confidence interval 1.03 to 5.43, P = 0.04). CONCLUSIONS: Telomerase activity can be identified as an independent predictor for recurrence after resection of HCC.