Hypermethylation of E-cadherin,p16, p14, and RASSF1A genes in pathologically normal urothelium predict bladder recurrence of bladder cancer after transurethral resection

ObjectivesThis study investigated the hypermethylation of E-cadherin, p16, p14, and RASSF1A in pathologically normal urothelium to predict recurrence of bladder cancer after transurethral resection.Materials and methodsSamples of bladder tumor and paired pathologically normal urothelium were obtained from 50 bladder cancer patients. The status of promoter hypermethylation in these four genes was investigated by methylation-specific polymerase chain reaction. The clinicopathologic data in these patients were also analyzed in order to evaluate the clinical implication of aberrant methylation in bladder cancer recurrence.ResultsHypermethylation of E-cadherin (30%), p16 (16%), p14 (14%), and RASSF1A (36%) was detected in the pathologically normal urothelium samples. Promoter hypermethylation occurred frequently in both pathologically normal urothelium and tumor samples from bladder cancer patients, and increased with progression from normal to bladder cancer at E-cadherin (P = 0.067), p16 (P < 0.001), p14 (P = 0.01), and RASSF1A (P = 0.01). No significant correlation was observed between hypermethylation in any genes and muscle/organ invasion and stage/grade, except p14. However, p14 hypermethylation in pathologically normal urothelium samples was associated with shorter recurrence-free interval (P = 0.019).Conclusionsp14 hypermethylation could be involved in early stage of bladder carcinogenesis, and p14 hypermethylation in pathologically normal urothelium samples should be considered a predictor of bladder cancer recurrence.     

Genetic detection of bladder cancer by microsatellite analysis of p16, RB1 and p53 tumor suppressor genes

PURPOSE: We investigated the incidence of genetic alterations in urine specimens from patients with bladder cancer. MATERIALS AND METHODS: A total of 28 cytological urine specimens were assessed for microsatellite alternations, and 15 microsatellite markers were located on p53, RB1 and p16 regions. In 15 patients DNA from tumor specimens was also available. RESULTS: Loss of heterozygosity was detected in 26 of 28 patients (93%) in at least 1 microsatellite marker. Allelic losses were found in 18 patients (64%) for the p16 locus, in 8 (29%) for the RB1 locus and in 17 (61%) for the p53 region. In contrast, no microsatellite alterations were found in the normal group without evidence of bladder cancer. In 11 cases genetic alterations in the cytological urine specimens were not detectable in the corresponding tumor specimen, suggesting heterogeneity of bladder cancer. CONCLUSIONS: The detection of loss of heterozygosity in cytological urine specimens may be a prognostic indicator of early detection of bladder cancer. Our results suggest that microsatellite analysis of urine specimens represents a novel, potentially useful, noninvasive clinical tool to detect bladder cancer.     

膀胱移行细胞癌患者RASSF1A蛋白表达和启动子区甲基化的研究

目的:探讨RASSFlA(RAS association domain family1A)蛋白表达水平与启动子甲基化的关系.方法:应用免疫印迹技术(western-blot)检测10例正常膀胱组织和23例膀胱移行细胞癌(Badder transitional cell carcinoma,BTCC)组织中RASSFlA蛋白表达水平;用甲基化特异性PCR(Methylation-Specific PCR,MSP)方法检测正常膀胱组织,BTCC组织中RASSF1A基因启动子CPG岛甲基化状态.结果:RASSF1A蛋白在正常膀胱组织中全部表达,在BTCC组织中表达率为30.4%(7/23),二组间表达差异有统计学意义(P＜0.05),但各肿瘤分期、病理分级间的表达差异无统计学意义(P＞0.05).在正常膀胱组织中,RASSF1A基因启动子未发生甲基化;在BTCC组织中,RASSF1A基因启动子甲基化频率为60.9%(14/23),二组间表达差异有统计学意义(P＜0.05).在14份启动子异常甲基化的BTCC标本中,13份同时伴有RASSFIA蛋白表达缺失或下调,两者存在明显相关性(P＜0.05).结论:RASSFlA基因启动子在BTCC组织中发生异常甲基化,使RASSF1A蛋白表达缺失,推测RASSFIA基因启动子CPG岛异常甲基化导致RASSF1A基因失活从而引起肿瘤的发生,而与肿瘤的进展可能无关.     

Immunohistochemical expression of p53, p21, p16, and cyclin D1 in superficial bladder cancer. A tissue microarray study

Introduction and objectivesTo retrospectively assess the relationship between immunohistochemical expression of p53, p21, p16, and cyclin D1, with recurrence, progression and survival in superficial bladder cancer.Methods163 patients undergoing transurethral resection for superficial bladder cancer between February 1995 and March 2004. Tumor samples were included in a tissue microarray support that was serially sectioned for immunohistochemical staining.Grade and stage associations for each marker were evaluated by the Chi-square test. Assessment of the relationship with recurrence, progression, and survival Kaplan-Meier curves and log-rank test were used.ResultsThere were no statistically significant differences in marker expression depending on tumor grade and stage, with the exception of Cyclin D1, that was significantly different depending on tumor stage (p=0.030).p21 expression was related to tumor recurrence (p=0.035), progression (p=0.008) and survival (p=0.034). p16 expression was also related to recurrence (p=0.048) and survival (p=0.047), but not to tumor progression (p=0.116).p53 and Cyclin D1 were not statistically associated with tumor recurrence, progression or survival.ConclusionsIn our experience, only p16 and p21 may be useful in the management of superficial bladder tumors, as they are predictors of recurrence and survival in Ta and T1 patients.     

RASSF1A在胃癌中的表达及其甲基化状态的研究

目的：研究胃癌组织中RASSF1A基因启动子区甲基化及其蛋白表达情况,分析两者之间的关系及其在胃癌发生发展中的作用。方法：应用免疫组化SP法检测39例胃癌组织,39例相应癌旁组织及30例对照组织中RASSF1A蛋白表达,应用甲基化特异性PCR法检测上述组织RASSF1A启动子CpG岛甲基化状态。结果：1）胃癌组RASSF1A蛋白表达阳性率53.8%明显低于癌旁组97.4%及正常对照组100%（P〈0.05）;2）胃癌组织中RASSF1A基因启动子区甲基化率为64.1%,显著高于癌旁组织甲基化率7.7%及对照组0%（P〈0.05）;3）在胃癌组织中,甲基化组RASSF1A蛋白表达明显低于非甲基化组（P〈0.05）。结论：胃癌组织RASSF1A蛋白表达缺失或低下,与其启动子甲基化程度增高显著相关,RASSF1A启动子甲基化在胃癌发生、发展中起一定作用。     

A study comparing various non-invasive methods of detecting bladder cancer in urine

OBJECTIVES: To compare the nuclear matrix protein (NMP)-22 assay, bladder tumour specific antigen (BTAstat) test, telomerase activity (using the telomeric repeat amplification protocol assay, TRAP) and a haemoglobin dipstick test for their ability to replace voided urine cytology (VUC) for detecting bladder cancer. PATIENTS AND METHODS: The study included 120 urological patients prospectively recruited and assessed before surgery. A single freshly voided urine sample (approximate 100 mL) was collected from each patient and aliquoted for each test. All assays were conducted according to the manufactures' guidelines; 79 patients were tested for telomerase activity. The results were then compared with VUC and the diagnosis confirmed by cystoscopy and histology. RESULTS: Fifty-two patients had histologically confirmed transitional cell carcinoma. The overall sensitivity for BTAstat, NMP22, telomerase, VUC and dipstick testing was 63%, 81%, 84%, 48% and 50%, respectively. Combining the results for telomerase and NMP22 gave a sensitivity of 100%. For G1 tumours the respective sensitivities were 23%, 62%, 56%, 23% and 15%, for G2 tumours, 68%, 86%, 92%, 50% and 41% and for G3 tumours 88%, 88%, 100%, 71% and 82%. For pTa tumours the respective detection rates were 48%, 70%, 84%, 39% and 30%, for pT1 tumours 80%, 90%, 90%, 50% and 50%, for pT2/pTis tumours, 100/100%, 100/100%, 100/100%, 88/100% and 88/83%. The overall specificity for the respective tests was 82%, 87%, 93%, 87% and 54%; combining the results of NMP22 and telomerase activity increased the specificity to 96%. CONCLUSIONS: There was significantly better detection than VUC when using the NMP22 and TRAP assay, especially for well-differentiated (P < 0.001 and 0.0027, respectively) and superficial tumours (P < 0.001 and 0.034, respectively). Combining the results of NMP22 and telomerase activity yielded values comparable with cystoscopy.     

膀胱癌患者血浆和尿液中p53基因突变的研究及其意义

目的：探讨体液中检测膀胱癌肿瘤细胞DNA的方法和意义。方法：应用聚合酶链反应（PCR）扩增30例膀胱癌患者血浆和尿液中p53基因第5、6、7和8我显子片段，应用单链构象多态分析（SSCP）法检测变异，并对变异片段测序。对照组中的检测结果，比较差异。结果：组织中可以检测到p53基因8种改变，血浆中检测到4种，与组织相比符合率为50.0％。尿液中检测到8种符合率62.5％。体液检测突变性质与相应组织是一致的。免疫组织化学染色以阳性细胞占20％为阳性界值时，结果与测序法接近。结论：体液中检测实体肿瘤细胞的突变基因片段用来诊断肿瘤或提供肿瘤生物学行为的相关信息，是一种有前途的诊断方法。     

尿液中多基因启动子甲基化联合检测诊断膀胱癌的研究

目的探索一种更加有效的通过尿液细胞中多基因甲基化分析诊断膀胱癌的方法。方法应用甲基化特异性PCR(MSP)技术检测37例膀胱癌患者和31例非膀胱癌对照患者尿液中P14、RASSF1A、SLIT2、RASAL1基因启动子区的甲基化状态。结果尿液细胞中通过P14、RASSF1A、SLIT2、RASAL1基因启动子区的甲基化状态检测膀胱癌的敏感性分别为75.7%、75.7%、62.2%、37.8%,与此相对它们的特异性为77.4%、90.3%、90.3%、93.5%。当4个基因中只有一个出现甲基化就诊断为膀胱癌时的敏感性为89.2%。结论膀胱癌患者尿液中多基因甲基化联合分析可能是一种高效的诊断膀胱癌的方法。     

Immunoreactivity of bcl-2, p53 and EGFr is associated with tumor stage, grade and cell proliferation in superficial bladder cancer

Immunoreactivity of bcl-2, p53, the epidermal growth factor (EGFr) and Ki-67 (MIB-1) proteins was assessed by immunohistochemistry in 185 patients with superficial bladder cancer (SBC) in order to evaluate their usefulness as indicators of tumor progression. Forty-one percent of the tumors were bcl-2 positive, 36% of them were positive for p53 (over 20% of nuclei), while 41% were positive for EGFr, and 30% of the tumors were MIB-1 positive (proliferation index > 15%). Immunoreactivity of all analyzed proteins was highly significantly related to tumor grade and stage. Tumors which were bcl-2, p53 or EGFr positive were also rapidly proliferative (MIB-1 score > 15%). The obtained results suggest that all analyzed proteins may have prognostic significance in SBC. The prognostic value of the abnormal immunolabeling of the analyzed proteins will be established after an adequate follow-up period of this same cohort of patients.Finnbladder III Group: M. Ala-Opas, K. Tuhkanen, Kuopio University Hospital; T. Forsell, Kymenlaakso Central Hospital; Kotka, P. Granbacka, Pietarsaari District Hospital; O. Hynninen, Lahti City Hospital; K. Jauhiainen, T.Liukkonen, Mikkeli Central Hospital; H. Juusela, District Hospital of Jorvi; Espoo, P. Kemppainen, Central Hospital of Kainuu; Kajaani, H. Korhonen, Satakunta Central Hospital; Pori, T. Lahdes-Vasama, S. Rannikko, M. Ruutu, Helsinki University Hospital; K. Lehtoranta, M. Talja, Päijät-Home Central Hospital; Lahti, J. Häkkinen, P. Hällström. M. Kontturi, O. Lukkarinen, M. Raitanen, Oulu University Hospital; M. Nurmi, P. Rajala, Turku University Hospital; J. Ottelin, Kemi Central Hospital; P. Pellinen, Kokkola Central Hospital; J.Permi, V.-M. Puolakka, Lappeenranta Central Hospital; E. Rintala, Helsinki City Hospital; T.L. Tammela, H. Tainio, Tampere University Hospital; R. Usenius, Jyväskylä Central Hospital     

The role of bcl-2, p53, and ki-67 index in predicting tumor recurrence for low grade superficial transitional cell bladder carcinoma

PURPOSE: We assess the prognostic significance of bcl-2 expression, p53 mutation and ki-67 index for low grade, superficial transitional cell bladder carcinoma. MATERIALS AND METHODS: The medical records of 93 cases of primary, low grade (24 G1, 69 G2), superficial (70 pTa, 23 pT1) transitional cell carcinoma of the bladder were reviewed. Association of bcl-2, p53 and ki-67 index immunoreactivity with tumor grade and stage was examined. Prognostic significance of tumor grade, pathological stage, bcl-2 expression, p53 mutation and ki-67 index in predicting tumor recurrence was assessed. RESULTS: Of the tumors 60 (70%) had p53 mutation and 9 (10.5%) expressed bcl-2. These 2 markers did not relate to tumor grade or pathological stage. Median ki-67 index was 10.9% and positively correlated with tumor grade. Recurrence was noted in 34.9% of patients with a median followup of 26 months (range 1 to 84). The ki-67 index was the only significant prognostic indicator in univariate and multivariate analyses. This marker can further distinguish grade 2 tumors with a favorable prognosis from those with an unfavorable outcome. CONCLUSIONS: The ki-67 labeling index is an independent predictor of tumor recurrence for patients with primary superficial, low grade bladder cancers.     

Loss of P16 expression and chromosome 9p21 LOH in predicting outcome of patients affected by superficial bladder cancer

OBJECTIVES: To evaluate the prognostic role of p16 expression and loss of heterozygosity (LOH) on chromosome 9p21 in patients affected by low-grade (G1-G2) urothelial bladder cancer. METHODS: Fifty-six consecutive patients with diagnosis of urothelial bladder cancer were enrolled in this prospective study. LOH analysis was performed on a blood/tumor pair sample of each patient, by using polymerase chain reaction analysis. The D9S171 (9p21) locus on chromosome 9 was investigated. All tumors were stained immunohistochemically for p16. Data from p16 and LOH analyses were compared with follow-up data to evaluate the prognostic role of these molecular markers. RESULTS: Loss of p16 expression was found in 33 patients (58.9%) and was significantly associated with the reduced recurrence-free probability (P < 0.0001). No correlations were reported with stage (P = 0.162) or grade (P = 0.051). Forty-three patients (76.7%) showed LOH on chromosome 9p21 (D9S171). A significant association was observed between loss of p16 expression and LOH on chromosome 9p21 (P = 0.005). The Kaplan-Meier curves showed a significant correlation between recurrence-free status and p16 expression (P = 0.0001). By multivariate analysis, p16 expression (P = 0.002) and number of lesions (P = 0.002) were identified as independent tumor recurrence factors. CONCLUSIONS: Our study highlights the prognostic role of p16 in predicting the recurrence-free probability in patients affected by low-grade urothelial bladder and highlights the fact that this method could be used in everyday urologic clinical practice to better characterize the natural history of urothelial bladder carcinomas.     

膀胱癌和肾癌组织中RASSF1A基因的甲基化改变

目的研究RASSF1A基因启动子的甲基化状态及在膀胱癌和肾癌发生中的作用。方法采用甲基化特异性PCR(MSP)技术检测45例手术切除的膀胱癌组织和相应癌旁正常组织标本、9例电切膀胱癌组织、3例非肿瘤患者正常膀胱组织、12例肾癌组织和相应癌旁正常组织标本中RASSF1A基因的甲基化情况。结果膀胱癌组织中RASSF1A基因异常甲基化55.6%(30/54),其中手术切除组57.8%(26/45),电切癌组织异常甲基化4例,癌旁正常组织基因异常甲基化1例;肾癌组织中基因异常甲基化66.7%(8/12),相应癌旁正常组织中未发现基因甲基化。3例正常膀胱组织标本中未发现基因异常甲基化。膀胱癌组织中RASSF1A基因甲基化率有随组织分期升高的趋势,但与临床病理参数间无明显相关性。结论膀胱癌和肾癌组织中RASSF1A基因启动子高度甲基化,表明该基因甲基化可能与2种肿瘤的发生相关。     

基因启动区异常甲基化导致肝癌中RASSF1A基因外失活的研究

目的观察肝癌组织中的抑癌基因RASSF1A的表达情况和由于启动区异常甲基化导致其基因外失活的状况，并分析DNA异常甲基化与肝癌临床相关因素之间的关系。方法利用RT—PCR和MS-PCR的方法，结合DNA测序和Taq I酶切消化法，分析了24例肝癌标本、4株肝癌细胞株（SMMC7721、HepG2、BEL7402和BEL7703）中RASSF1A基因的表达情况，以及其基因启动区异常甲基化的情况。采用甲基化抑制剂5＇-Aza—CdR处理肝癌细胞株，观察RASSF1A重新表达的情况。结果66．7％的肝癌组织未表达RASSF1A；4株肝癌细胞株中仅SMMC7721检测到RASSF1A的表达。83．3％的肝癌组织及4株肝癌细胞株都发生了异常甲基化，而正常肝组织和正常肝细胞株（L02）中却未发现甲基化。甲基化与肝硬化、乙肝表面抗原、肿瘤分化程度及血管浸润和远处转移有相关性。原来RASSF1A表达失活的3株肝癌细胞株经甲基化抑制剂5＇-Aza—CdR处理后，又重新恢复了表达。结论基因转录启动区的异常甲基化是导致肝癌中RASSF1A表达失活的主要原因。检测RASSF1A启动区异常甲基化可作为一种有潜在应用价值的生物分子指标来用于肝癌的早期发现和早期诊断，以及预后的判断。     

Expression of p16 and cyclin D1 in bladder cancer and correlation in cancer progression

INTRODUCTION: Gene p16 encodes a cyclin-dependent kinase inhibitor which functions to regulate cyclin D1, cell cycle progression and malignancies. The relationship between p16 and cyclin D1 is thought to alter bladder cancer formation and tumor progression. We aimed to investigate the expression of p16 and cyclin D1 genes in order to evaluate their clinical significance in bladder cancer. MATERIALS AND METHODS: Tissue samples from 67 patients with transitional cell carcinoma were examined with an immunohistochemical stain for the expression of p16 and cyclin D1 genes. The expression rate was compared to 12 normal urinary bladder mucosa samples obtained from transurethral surgery from noncancer patients. RESULTS: The results revealed significant differences between normal bladder mucosa (100%) and cancer tissue (40.3%) for the positive staining of p16 protein (p < 0.001), while positive staining for the cyclin D1 protein in the patient group (67.2%) was significantly higher (p = 0.003) than that in the control group (16.7%). With the progression of tumor grade and clinical staging the positive rate of p16 gene expression increased, whereas, that of cyclin D1 decreased. Expression of the p16 gene in the non-invasive group was greater than that in the invasive group and a lower expression rate of the cyclin D1 gene in the non-invasive group compared to the invasive group. CONCLUSIONS: The results revealed that expression of the p16 gene is inversely proportional to the expression of the cyclin D1 gene. Therefore, abnormal expression of the p16 and cyclin D1 genes play important roles in tumorigenesis and tumor progression.     

反义增殖细胞核抗原联合p16基因转染抑制膀胱癌细胞生长的研究

目的 探讨膀胱癌联合基因治疗的新策略。方法 反义增殖细胞核抗原(PCNA)联合p16转染膀胱癌细胞，观测共转染1—7d后癌细胞增殖活性、DNA合成速率、细胞周期时相、克隆形成能力、细胞凋亡和PCNA、p16基因表达情况。结果 联合转染后癌细胞PCNA表达减弱，p16表达显著增强，增殖活性抑制15．45％—68．47％(P＜0．01)，DNA合成速率减慢65．77％(P＜0．01)，细胞周期阻滞于G0／G1期，克隆形成率抑制64．49％(P＜0．01)，凋亡率为22．00％(P＜0．01)。结论 反义PCNA与p16共转染具有抑制增殖、诱导凋亡的双重作用，有望成为膀胱癌联合基因治疗的新途径。     

Malignant transformation-related genes in meningiomas: allelic loss on 1p36 and methylation status of p73 and RASSF1A

OBJECT: Analysis of meningiomas supports the suggestion that loss of heterozygosity (LOH) of chromosome arm 1p plays an important role in malignancy. The aim of this study was to identify genes related to meningioma progression from the benign state to the atypical and anaplastic states by examining 1p LOH and the promoter methylation of RASSF1A and p73. METHODS: The authors studied 40 surgical specimens (22 WHO Grade I, 11 Grade II, and seven Grade III) obtained in 37 patients with meningioma. The LOH at 1p36 was analyzed using microsatellite markers, and promoter methylation of p73 and RASSFIA was analyzed using methylation-specific polymerase chain reaction. RESULTS: No 1p LOH was detected in the Grade I tumors, whereas it was detected in more than 80% of the Grade II and III tumors. Methylation of the p73 promoter was observed in 81.8 and 71.4% of the Grade II and III tumors, respectively, but it was not observed in any of the Grade I tumors; methylation of the RASSF1A promoter was observed in 18.2, 63.6, and 42.9% of the Grade I, II, and III tumors, respectively. Interestingly, 1p LOH and p73 promoter hypermethylation were detected in the malignantly transformed tumors but not in the lower-grade primary ones. CONCLUSIONS: Based on the hypothesis that meningiomas cumulatively acquire genetic alterations and thus progress from the benign to the atypical and anaplastic states, genetic alterations in the methylation status of p73 or RASSF1A along with 1p LOH may result in the malignant transformation of a meningioma. This type of genetic fingerprint may play both diagnostic and therapeutic roles.     

Diagnostic efficacy of the combination of urine cytology, urine analysis and history in the follow-up of bladder carcinoma

In the follow-up of low stage, low grade transitional cell carcinoma of the bladder, cystoscopy is used as a diagnostic standard. Because of the lack of well defined prognostic parameters, cystoscopic follow-up is based upon empirical grounds. In this study, 82 patients with a primary superficial transitional cell carcinoma of the bladder were studied with respect to the time interval before recurrence. The mean number of cystoscopies leading to detection of recurrence (i.e. the ratio of positive to negative cystoscopy) was reviewed. Eighteen cystoscopies had to be done to detect each recurrence. Because of this excessive number of cystoscopies, the diagnostic value of the combination of red cell count in urine, cytology and history of micturition symptoms and haematuria was assessed in a retrospective study of 86 recurrences of bladder carcinoma. The results indicated that the combination of these non-invasive diagnostic tests may constitute a sensitive procedure for the follow-up of bladder tumours. In the case of T1G3 and muscle-invasive recurrences (greater than T1), the sensitivity rate was 100%.     

Evaluation of p21WAF1/CIP1 and cyclin D1 expression in the progression of superficial bladder cancer

Immunoreactivity of p21^WAF1/CIP1 and cyclin D₁ proteins was assessed in a cohort of 207 patients with superficial (pTa-pT₁) bladder cancer followed up for a mean of 4.9 years. The results of the immunostainings were compared with T category, WHO grade, tumor cell proliferation rate (MIB-1 score), the expressions of p53 and bcl-2 as well as survival. Sixty-eight percent and 75% of the tumors were p21^WAF1/CIP1 positive (≥5% of cells positive) and cyclin D₁ positive (≥10% of cells positive), respectively. The p21^WAF1/CIP1 expression was related to cyclin D₁ immunolabelling (P < 0.001) but not to the other variables studied. The expression of cyclin D₁ was inversely associated with T category (P=0.001), WHO grade (P=0.006), MIB-1 score (P=0.014), p53 expression (P=0.001), and bcl-2 (P=0.011) immunoreactivity. In univariate analysis, T category (P=0.0001), WHO grade (P < 0.0001), MIB-1 score (P < 0.0001), bcl-2 (P=0.0092), p53 (P=0.0016) and p21^WAF1/CIP1 (P=0.009) expressions were significant prognostic factors with regard to tumor progression, whereas cyclin D₁ was without any prognostic significance (P=0.1). Out of 123 p21 positive tumors 21 progressed, whereas only 2 out of 58 p21 negative tumors progressed. In multivariate analysis, the MIB-1 score was the only independent predictor of cancer-specific survival (P=0.03), whereas tumor grade (P=0.002) and cyclin D₁ expression (P=0.04) were independent predictors of tumor recurrence. Only the WHO grade (P=0.04) retained its prognostic value indicating the risk of progression. We suggest that in superficial bladder cancer p21^WAF1/CIP1 and cyclin D₁ immunohistochemistry provide no additional prognostic information compared with already established prognostic factors for predicting the risk of progressive disease. Received: 13 September 1999 / 22 March 2000