Giovanni Casetta

Polymorphisms/Haplotypes in DNA Repair Genes and Smoking: A Bladder Cancer Case-Control Study

Bladder cancer is associated with tobacco smoking and occupational exposure. The repair of DNA damage has a key role in protecting the genome from the insults of cancer-causing agents. We analyzed 13 polymorphisms in seven DNA repair genes belonging to different repair pathways [X-ray repair cross-complementing group 1 (XRCC1): 26304C>T, 26651A>G, 28152A>G; xeroderma pigmentosum-D (XPD): 23591A>G, 35931A>C; excision repair complementing defective in Chinese hamster, group 1 (ERCC1): 19007C>T; XRCC3: 4541T>C, 17893A>G, 18067C>T; proliferating cell nuclear antigen (PCNA): 6084G>C; ERCC4: 30028C>T, 30147A>G; and XRCC2-31479A>G] in 317 incident bladder cancer patients and 317 controls. After adjustment for age and smoking, the PCNA-6084C variant was significantly associated with an increased risk of bladder cancer [CC + CG versus GG, odds ratio (OR), 1.61; 95% confidence interval (95% CI), 1.00-2.61], as well as the XRCC1-26651G variant (GG+AG versus AA: OR, 1.73; 95% CI, 1.17-2.56). After stratifying by smoking habits, an elevated risk for carriers of the XRCC3-18067T allele was detected both in current (TT versus CC: OR, 2.65; 95% CI, 1.21-5.80; CT versus CC: OR, 1.96; 95% CI, 1.09-3.52) and never smokers (TT versus CC: OR, 4.34; 95% CI, 1.14-16.46; CT versus CC: OR, 2.02; 95% CI, 0.72-5.66), whereas an opposite and slightly weaker effect was associated to the XRCC3-17893G allele in current smokers (GG versus AA: OR, 0.30; 95%CI, 0.11-0.82; AG versus AA: OR, 0.73; 95% CI, 0.42-1.27). XRCC3,XRCC1, ERCC4, and XPD-ERCC1 haplotype frequencies were estimated by the maximum likelihood method. The XRCC3-TAT haplotype was associated with an enhanced risk in the current smokers group (OR, 1.62; 95% CI, 1.15-2.29), whereas a reduction of the risk in the overall sample was observed in the presence of the XRCC3-TAC (OR, 0.69; 95% CI, 0.50-0.97). A significant protective effect of the XPD-ERCC1-ACC haplotype was observed among never smokers (OR, 0.16; 95% CI, 0.03-0.81). Our results suggest that polymorphisms and/or haplotypes in XRCC3, XRCC1, and PCNA genes and spanning XPD-ERCC1 region may modulate bladder cancer risk and that some of these effects may preferentially affect current smokers.

ERCC1 haplotypes modify bladder cancer risk: a case-control study.

Bladder cancer risk is highly influenced by environmental and/or predisposing genetic factors. In the last decades growing evidence of the major role played by DNA repair systems in the developing of bladder cancer has been provided. To better investigate the involvement of DNA repair genes previously reported to be significantly associated with bladder cancer risk, we examined in a case-control study (456 cases and 376 hospital controls) 36 single nucleotide polymorphisms (SNPs) in 10 DNA repair genes, through a better gene coverage and a deep investigation of the haplotype role. A single SNP analysis showed a significantly increased risk given by XRCC1-rs915927 G allele (OR=1.55, CI 95% 1.02-2.37 for dominant model) and a protective effect of the rare alleles of 3 ERCC1 SNPs: rs967591 (OR=0.66, CI 95% 0.46-0.95), rs735482 (OR=0.62, CI 95% 0.42-0.90) and rs2336219 (OR=0.63, CI 95% 0.43-0.93). Haplotype analysis revealed that cases had a statistically significant excess of XRCC3-TAGT and ERCC1-GAT haplotypes, whereas ERCC1-AAC, MGMT-TA, XRCC1-TGCC and ERCC2-TGAA haplotypes were significantly underrepresented. Together with other published data on large case-control studies, our findings provide epidemiological evidence supporting a link between DNA repair gene variants and bladder cancer development, and suggest that the effects of high-order interactions should be taken into account as modulating factors affecting bladder cancer risk. A detailed characterization of DNA repair genetic variation is warranted and might ultimately help to identify multiple susceptibility variants that could be responsible for joint effects on the risk.

Shorter Leukocyte Telomere Length Is Independently Associated with Poor Survival in Patients with Bladder Cancer

Background: Shorter telomere length (TL) has been reported to be associated with increased risk of early death in elder individuals. Telomere shortening has been also related to chromosomal instability, which may possibly contribute to the development of several types of digestive or urogenital system cancers and smoking-related tumors. Therefore, we investigated the impact of TL on bladder cancer survival. Methods: TL was measured in leukocyte DNA from whole peripheral blood using quantitative real-time PCR in 463 patients with bladder cancer from a total 726 cases who were followed for up to 18 years. Results: Patients with muscle-invasive tumor/any grade had shorter telomere than patients with non–muscle-invasive tumor/high-grade and with non–muscle-invasive tumor/non–high-grade (TL reference 0.7 ± 0.2; vs. respectively, 0.8 ± 0.2, P = 3.4 × 10−2 and 0.8 ± 0.2, P = 3.6 × 10−2). Moreover, patients in the lowest quartiles of TL were associated with decreased survival after diagnosis (log-rank test, P = 3.9 × 10−4). A Cox regression adjusted by age, cancer aggressiveness, Bacillus Calmette-Guérin, radical cystectomy, radiotherapy, and chemotherapy showed an independent effect of TL on bladder cancer survival (HR, 3.9; 95% confidence interval, 1.7–9.1; P = 1.2 × 10−3). Conclusions: Our results suggest that leukocyte TL is only partly related to tumor aggressiveness and that shorter telomeres act as independent prognostic predictor of survival in patients with bladder cancer. TL information may allow to better select therapeutic approaches in patients with the same stage and grade. Impact: Blood leukocyte TL levels could provide an additional noninvasive prognostic marker to better predict survival and personalize therapies in patients with bladder cancer. Cancer Epidemiol Biomarkers Prev; 23(11); 2439–46. ©2014 AACR.

Bladder Pheochromocytoma: A 3-Year Follow-Up afterTransurethral Resec tion (TURB)

We report a case of a 75-year-old female with pheochromocytoma of the bladder. Clinical evaluation included ultrasonography, intravenous pyelography, CT scan, I-MIBG scintiscan. A transurethral resection was performed for a exophytic tumor of 2 cm diameter. The histological result indicated the diagnosis of bladder pheochromocytoma. Three years later the patient remains disease free. Preoperative diagnosis is established by determination of blood and urine levels of catecholamines and their metabolites is a nonspecific diagnostic tool. The sensitivity of CT scan is 82%. Iodine-methyliodobenzylguanidine (I-MIBG), used by scintiscanning, specifically accumulates in pheochromocytomas. Life-long follow-up is necessary to diagnose late recurrences.

Polymorphisms in the XRCC1 gene modify survival of bladder cancer patients treated with chemotherapy.

Survival of bladder cancer patients depends on several factors including disease stage and grade at diagnosis, age, health status of the patient and the applied treatment. Several studies investigated the role of DNA repair genetic variants in cancer susceptibility, but only few studies investigated their role in survival and response to chemotherapy for bladder cancer. We genotyped 28 single nucleotide polymorphisms (SNP) in DNA repair genes in 456 bladder cancer patients, reconstructed haplotypes and calculated a score for combinations of the SNPs. We estimated Hazard Ratios (adjHR) for time to death. Among patients treated with chemotherapy, variant alleles of five SNPs in the XRCC1 gene conferred better survival (rs915927 adjHR 0.55 (95%CI 0.32–0.94); rs76507 adjHR 0.48 (95%CI 0.27–0.84); rs2854501 adjHR 0.25 (95%CI 0.12–0.52); rs2854509 adjHR 0.21 (95%CI 0.09–0.46); rs3213255 adjHR 0.46 (95%CI 0.26–0.80). In this group of patients, an increasing number of variant alleles in a XRCC1 gene score were associated with a better survival (26% decrease of risk of death for each additional variant allele in XRCC1). By functional analyses we demonstrated that the previous XRCC1 SNPs confer lower DNA repair capacity. This may support the hypothesis that survival in these patients may be modulated by the different DNA repair capacity determined by genetic variants. Chemotherapy treated cancer patients bearing an increasing number of “risky” alleles in XRCC1 gene had a better survival, suggesting that a proficient DNA repair may result in resistance to therapy and shorter survival. This finding may have clinical implications for the choice of therapy.

BTA Quantitative Assay and NMP22 Testing Compared with Urine Cytology in the Detection of Transitional Cell Carcinoma of the Bladder

Purpose: Both BTA TRAK and NMP22 urine concentrations have shown a sensitivity superior to urine cytology in the detection of bladder cancer. We compared these tumor markers with urine cytology performed on 3 consecutive samples and evaluated by an expert cytopathologist. Patients and Methods: The investigations were conducted on 94 patients undergoing a diagnostic cystoscopy for a high suspicion of bladder cancer (group 1) and on 102 patients with previous history of transitional cell carcinoma awaiting a follow-up cystoscopy (group 2). Biopsy specimens were obtained also from tumor negative patients. Immunoassays for BTA TRAK and NMP22 were carried out according to standard methods. The choice of the cut-off was based on the ground of sensitivity and specificity curves intersection. Urine cytology results were expressed as positive, negative and ‘dubious’. Results: Overall sensitivity was 56% for NMP22 (cut-off 11 U/ml) and 57% for BTA TRAK (cut-off 60 U/ml). When dubious results were considered as positive cases, urine cytology achieved a sensitivity of 73.3%. Assuming dubious cases as negative results, urine cytology sensitivity resulted 59.3%. When the 2 groups of patients were evaluated separately with different cut-off, there was no significant gain in sensitivity for BTA TRAK and NMP22 over urine cytology. Conclusions: Urine cytology performed on 3 samples showed the highest sensitivity and specificity. The diagnostic advantage of urine cytology over BTA TRAK and NMP22 was maintained when patients were stratified by tumor grade.

Carcinogen-DNA adducts in bladder biopsies and urothelial cells: a risk assessment exercise.

We have determined the levels of DNA adducts (using 32P-postlabelling) in the biopsies of 20 bladder cancer patients and in the exfoliated bladder cells of 36 healthy volunteers. The aims of the study were (a) to estimate the concentration of DNA adducts in cancer cases and controls according to the level of smoking; and (b) to investigate whether bladder cancer cases had higher levels of adducts in bladder cells than healthy controls had. A dose-response relationship between smoking levels and adduct levels was present among both cancer cases and controls. Cancer cases and the controls had similar adduct levels for the same level of smoking. According to a risk assessment exercise, adduct levels among heavy smokers were roughly comparable with those found in mice and dogs treated with bladder carcinogens, at doses which induce a 50% lifetime risk of bladder cancer.

Bladder tumor antigen assay as compared to voided urine cytology in the diagnosis of bladder cancer.

BACKGROUND The study was aimed at comparing the diagnostic accuracy of the quantitative bladder tumor antigen (BTA) TRAK immunoassay with exfoliative urine cytology in the detection of primary and recurrent bladder cancer. METHODS The analysis was carried out on 194 high risk patients undergoing a diagnostic cystoscopy, 279 patients with previous history of transitional cell carcinoma awaiting a follow-up cystoscopy, and 45 healthy controls. Urine cytology was performed by a skilled cytopathologist on three consecutive samples. RESULTS BTA TRAK values resulted significantly higher in tumor positive cases than in absence of bladder tumor for both groups of patients. Non neoplastic urothelial diseases as well as the absence of mucosal abnormalities were associated with a marked increase in BTA TRAK levels with respect to the control group. Overall sensitivity and specificity was 63 and 63% for BTA TRAK (cut-off 34 U/ml), and 68.3 and 73.4% for urine cytology, respectively. The diagnostic advantage of urine cytology was maintained when patients were stratified by tumor grade. CONCLUSIONS The clinical performance of the BTA TRAK in the detection of primary or recurrent bladder cancer is acceptable and reproducible as shown by similar results with previous reports, although urine cytology performed on three samples showed the highest sensitivity and specificity.

Prognostic Factors of ‘High-Grade' Ta Bladder Cancers according to the WHO 2004 Classification: Are These Equivalent to ‘High-Risk' Non-Muscle-Invasive Bladder Cancer?

Objective: To determine the impact of prognostic factors of a series of high-grade Ta non-muscle-invasive bladder cancers (NMIBCs) according to the new International Society of Urological Pathology (ISUP) 1998/WHO 2004 grading system (previously classified as either TaG2 or TaG3). Methods: One hundred and thirty-one high-grade Ta (105 G2 and 26 G3) cases were identified after independent review by two pathologists. Univariable and multivariable Cox regression models addressed recurrence and progression-free survival. Progression was defined as appearance of any T ≥1 recurrence after complete TUR (type 1) or occurrence of T ≥2 (type 2). Results: Ten-year recurrence, type-1 and type-2 progression-free survival were 60, 75 and 95%, respectively. The previous grading system (G3 vs. G2) significantly predicted type 1 progression in the univariate model only. In the multivariate model, Ki67 was the only independent predictor of progression according to both definitions (HR = 5.25, p = 0.002 and HR = 6.16, p = 0.03, respectively). Conclusions: High-grade Ta NMIBC as defined by the WHO 2004 grading system cannot be equated with high-risk NMIBC. The risk of progression to muscle-invasive disease (type 2) is low, more in keeping with an intermediate-risk category of NMIBC. The previous WHO 1973 subcategorization into G2 and G3 is of little help in the prediction of outcome. Ki67 is a strong independent predictor of progression worthy of consideration for a clinical setting.

Prognostic Factors Including Ki-67 and p53 in Bacillus Calmette-Guérin-Treated Non-Muscle-Invasive Bladder Cancer: A Prospective Study

Objectives: To prospectively evaluate the prognostic utility of the traditional prognostic factors and molecular markers p53 and Ki-67 in a homogeneous series of patients with non-muscle-invasive bladder cancer (NMIBC) treated with Bacillus Calmette-Guérin (BCG). Patients and Methods: 192 intermediate- and high-risk NMIBC cases were enrolled. The variables in study were age, stage, grade, focality, tumour size, presence of associated carcinoma in situ, recurrence rate before BCG, maintenance for BCG, Ki-67 and p53. The endpoints considered were recurrence-free survival, progression-free survival, cancer-specific survival (CSS) and overall survival (OS). Results: T stage resulted in being associated with CSS, whereas age with OS. BCG maintenance was a significantly favourable independent predictor of OS, CSS, recurrence and progression. In univariate analysis, the labelling index of Ki-67 was significantly associated with OS, CSS and progression. Multivariate analysis, however, confirmed this association only for OS. On the contrary, the labelling index of p53 was a significant predictor of recurrence, both in uni- and multivariate analyses, but with a HR inferior to 1. Conclusions: Ki-67 was an independent predictor of survival. p53 overexpression showed a significant yet inverse correlation with recurrence, thus showing little clinical utility. Age, stage and maintenance were confirmed as independent predictors of BCG response.