A single-nucleotide polymorphism in the XPG gene, and tumour stage, grade, and clinical course in patients with nonmuscle-invasive neoplasms of the urinary bladder

Association of nonsynonymous SNPs of nucleotide excision repair genes ERCC4 rs1800067 (G/A) and ERCC5 rs17655 (G/C) as predisposing risk factors for gallbladder cancer

BACKGROUND

Deregulation of DNA repair mechanisms have been frequently demonstrated in the pathology of cancers including gallbladder cancer.

AIM

We aimed to investigate the association of ERCC4 rs1800067 (G/A) and ERCC5 rs17655 (G/C) with the predisposition in gallbladder cancer and its prognosis. We have also investigated the prognostic and diagnostic values of expression profiles of ERCC4 and ERCC5 in GBC.

METHODS

Polymorphisms of rs1800067 and rs17655 were genotyped by PCR-RFLP. The expression of these genes was analyzed by semi-quantitative PCR. Overall survival was analyzed using Kaplan-Meier plot and cox-regression analysis.

RESULTS

Patients with risk group genotypes of rs17655 have shorter overall survival in patients with presence of gallstone, T1+T2 tumor invasion, absence of lymph node involvement and early stages of tumor. Homozygous wild genotype (GG) of rs1800067 and homozygous mutant genotype (CC) of rs17655 together increases two-fold risk of the disease. The variant genotypes (GC/CC) of rs17655 show significantly higher level of ERCC5 expression.

CONCLUSION

Major allele of ERCC4 rs1800067 and minor allele of ERCC5 rs17655 are significantly associated with increased risk of GBC. Upregulation of ERCC4 and ERCC5 is an early event of development of GBC.

Systematic Review: Genetic Associations for Prognostic Factors of Urinary Bladder Cancer

INTRODUCTION

Many germline associations have been reported for urinary bladder cancer (UBC) outcomes and prognostic characteristics. It is unclear whether there are overlapping genetic patterns for various prognostic endpoints. We aimed to review contemporary literature on genetic associations with UBC prognostic outcomes and to identify potential overlap in reported genes.

METHODS

EMBASE, MEDLINE, and PubMed databases were queried for relevant articles in English language without date restrictions. The initial search identified 1346 articles. After exclusions, 112 studies have been summarized. Cumulatively, 316 single-nucleotide polymorphisms (SNPs) were reported across prognostic outcomes (recurrence, progression, death) and characteristics (tumor stage, grade, size, age, risk group). There were considerable differences between studied outcomes in the context of genetic associations. The most commonly reported SNPs were located in OGG1, TP53, and MDM2. For outcomes with the highest number of reported associations (ie, recurrence and death), functional enrichment annotation yields different terms, potentially indicating separate biological mechanisms.

CONCLUSIONS

Our study suggests that all UBC prognostic outcomes may have different biological origins with limited overlap. Further validation of these observations is essential to target a phenotype that could best predict patient outcome and advance current management practices.

Diagnostic and prognostic values of the mRNA expression of excision repair cross-complementation enzymes in hepatitis B virus-related hepatocellular carcinoma

Background

The current study aims at using the whole genome expression profile chips for systematically investigating the diagnostic and prognostic values of excision repair cross-complementation (ERCC) genes in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).

Materials and methods

Whole genome expression profile chips were obtained from the GSE14520. The receiver-operating characteristic (ROC) curve, survival analysis, and nomogram were used to investigate the diagnostic and prognostic values of ERCC genes. Investigation of the potential function of ERCC8 was carried out by gene set enrichment analysis (GSEA) and genome-wide coexpression analysis.

Results

ROC analysis suggests that six ERCC genes (ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, and ERCC8) were dysregulated and may have potential to distinguish between HBV-related HCC tumor and paracancerous tissues (area under the curve of ROC ranged from 0.623 to 0.744). Survival analysis demonstrated that high ERCC8 expression was associated with a significantly decreased risk of recurrence (adjusted P=0.021; HR=0.643; 95% CI=0.442–0.937) and death (adjusted P=0.049; HR=0.631; 95% CI=0.399–0.998) in HBV-related HCC. Then, we also developed two nomograms for the HBV-related HCC individualized prognosis predictions. GSEA suggests that the high expression of ERCC8 may have involvement in the energy metabolism biological processes. As the genome-wide coexpression analysis and functional assessment of ERCC8 suggest, those coexpressed genes were significantly enriched in multiple biological processes of DNA damage and repair.

Conclusion

The present study indicates that six ERCC genes (ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, and ERCC8) were dysregulated between HBV-related HCC tumor and paracancerous tissues and that the mRNA expression of ERCC8 may serve as a potential biomarker for the HBV-related HCC prognosis.

Study on bladder cancer susceptibility and genetic polymorphisms of XPC, XPG, and CYP in smokers and non-smokers

AIM

To investigate the gene susceptibility of bladder cancer and potential relation with smoking.

METHODS

An analysis of SNPs were conducted among DNA repair genes of XPC, XPG, XRCC1, and six members of metabolic enzyme gene CYP 450 via TaqMan Probe-based polymerase chain reaction. A total of 130 patients with bladder cancer and 304 healthy controls were involved.

RESULTS

Polymorphisms of XPC gene was related to bladder cancer. It was also related to smoking status in bladder cancer patients, as well as to tumour stage, male gender and older age. The XPG gene polymorphism was also related to bladder cancer yet it was prevalent in female non-smokers. No association was acquired for XRCC1 gene. The combination of more than 2 polymorphisms in DNA repair genes was associated with bladder cancer. No association was obtained in any of the metabolic enzyme gene of CYP450 with either bladder cancer or smoking status.

CONCLUSION

DNA repair genes XPC and XPG could be related to carcinogenesis and tumour progression of bladder cancer. Confirmation within larger population was warranted.

Germline prognostic markers for urinary bladder cancer: obstacles and opportunities

Urinary bladder cancer is a heterogeneous disease with diverse genetic and environmental risk factors that can influence disease risk or clinical course for recurrence, progression, and survival. Therefore, identification of these factors is paramount for disease prevention and optimal clinical management of bladder cancer patients. Of particular interest is the need to identify molecular biomarkers that can give accurate assessment of tumor biological potential and to predict treatment response. Recent advances in molecular biology, cytogenetic, and genomic research have spurred discovery efforts for novel genetic, epigenetic, and proteomic biomarkers that are prognostic for cancer. This review focuses on some of the important germ line polymorphisms found to be correlated with clinical outcomes in bladder cancer. So far, most of the identified candidate loci were based on prior knowledge of pathogenesis and had not been validated for clinical applications. The future challenges are to analyze the wealth of information from whole-genome studies, to understand the underlying biological mechanisms of these associations, the network of gene-gene and gene-environment interactions, and to apply these markers for the identification of high-risk population for targeted, personalized therapy.

Bladder cancer survival in a former industrial area in Saxony-Anhalt, Germany

Long-term follow-ups on bladder cancer patients from highly industrialized areas are rare. Therefore, we present a follow-up of bladder cancer patients from the greater area Lutherstadt Wittenberg, a center of the chemical industry of the former German Democratic Republic. Relapse-free survival times of 213 confirmed bladder cancer cases from the greater area Lutherstadt Wittenberg were collected between 2008 and 2009. Data on lifestyle and occupational exposure to potential carcinogens was recorded by questionnaire. Genotypes of N-acetyltransferase 2 (NAT2), glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1), rs710521, and rs9642880 were determined by standard methods. Cox models were used to evaluate differences in relapse-free survival. Clear differences in relapse-free survival could be observed for the number of relapses, multilocular tumor growth, and relapses with higher staging or grading than the primary tumor, as well as GSTT1. None of the other investigated polymorphisms showed significant impact on prognosis. This is the first study on two recently detected single-nucleotide polymorphisms (SNPs) showing that these polymorphisms may also contribute to shorter relapse-free times.

Nucleotide excision repair gene polymorphisms may predict acute toxicity in patients treated with chemoradiotherapy for bladder cancer

AIMS

Platinum-based chemoradiotherapy (CRT) as bladder conservation therapy has shown promising results for muscle-invasive bladder cancer. However, treatment-related toxicity remains a major consideration in therapeutic planning. Some common polymorphisms in genes involved in DNA repair (encoding enzymes that repair DNA damaged by platinum agents and ionizing radiation) are reported to result in modulation of the repair capacity. We investigated associations between functional genetic polymorphisms involved in DNA repair and acute toxicity of CRT to determine the predictive value of these polymorphisms for toxicity.

MATERIALS & METHODS

The study group comprised of 101 bladder cancer patients treated with platinum-based CRT, and seven polymorphisms in XPC (Lys939Gln, rs2228001), XPD (Lys751Gln, rs13181), XPG (Asp1104His, rs17655), XRCC1 (Arg399Gln, rs25487), XRCC3 (Thr241Met, rs861539), TP53 (Arg72Pro, rs1042522) and MDM2 (SNP309, T>G, rs2279744) were genotyped.

RESULTS

More than two total variant alleles in nucleotide excision repair genes, including XPC, XPD and XPG, were significantly associated with grade 3 or 4 neutropenia (adjusted odds ratio [aOR]: 6.8; 95% CI: 2.0-26; p = 0.0026). There were no significant associations between any genotypes and grade 2 or greater nausea/vomiting or diarrhea. Any grade 3 or 4 hematological toxicity was significantly associated with the Gln/Gln or Lys/Gln + Gln/Gln genotypes of XPC compared with Lys/Lys (aOR: 10; 95% CI: 2.0-65; p = 0.0070 or aOR: 6.3; 95% CI: 1.9-29; p = 0.0069; respectively).

CONCLUSION

These results suggest that nucleotide excision repair gene polymorphisms, especially in XPC, might potentially be predictive factors for acute toxicity of CRT for bladder cancer, helping individual patient selection for bladder conservation therapy. However, further studies with larger sample sizes are needed to draw final conclusions.

The effect of tobacco, XPC, ERCC2 and ERCC5 genetic variants in bladder cancer development

BACKGROUND

In this work, we have conducted a case-control study in order to assess the effect of tobacco and three genetic polymorphisms in XPC, ERCC2 and ERCC5 genes (rs2228001, rs13181 and rs17655) in bladder cancer development in Tunisia. We have also tried to evaluate whether these variants affect the bladder tumor stage and grade.

METHODS

The patients group was constituted of 193 newly diagnosed cases of bladder tumors. The controls group was constituted of non-related healthy subjects. The rs2228001, rs13181 and rs17655 polymorphisms were genotyped using a polymerase chain reaction-restriction fragment length polymorphism technique.

RESULTS

Our data have reported that non smoker and light smoker patients (1-19PY) are protected against bladder cancer development. Moreover, light smokers have less risk for developing advanced tumors stage. When we investigated the effect of genetic polymorphisms in bladder cancer development we have found that ERCC2 and ERCC5 variants were not implicated in the bladder cancer occurrence. However, the mutated homozygous genotype for XPC gene was associated with 2.09-fold increased risk of developing bladder cancer compared to the control carrying the wild genotype (p = 0.03, OR = 2.09, CI 95% 1.09-3.99). Finally, we have found that the XPC, ERCC2 and ERCC5 variants don't affect the tumors stage and grade.

CONCLUSION

These results suggest that the mutated homozygous genotype for XPC gene was associated with increased risk of developing bladder. However we have found no association between rs2228001, rs13181 and rs17655 polymorphisms and tumors stage and grade.

Germline genetic markers for urinary bladder cancer risk, prognosis and treatment response

After decades of research using a candidate gene approach, only NAT2 and GSTM1 have consistently been demonstrated to be germline genetic susceptibility markers for urinary bladder cancer (UBC). The recent shift to an agnostic genome-wide association approach led to the identification of several UBC susceptibility loci, and provided valuable leads for new mechanistic insights into UBC carcinogenesis. The markers do not have sufficient discriminatory ability yet to be applied for risk assessment in the population and the question is whether they ever will. Prognostic and predictive studies in UBC are still in their infancy compared with etiologic studies. In the future, focus on a genome-wide association approach possibly using whole-genome sequence data, consortia formation and meta-analyses, and blood and tumor tissue collection, preferably in the context of randomized controlled trials will stimulate well designed and sufficiently powered studies, and thereby enhance the elucidation of genetic prognostic and predictive markers.

Association of TP53 and MDM2 polymorphisms with survival in bladder cancer patients treated with chemoradiotherapy

Platinum-based chemoradiotherapy (CRT) as bladder conservation therapy has shown promising results for muscle-invasive bladder cancer. However, CRT might diminish survival as a result of the delay in cystectomy for some patients with non-responding bladder tumors. Because the p53 tumor suppression pathway, including its MDM2 counterpart, is important in chemotherapy- and radiotherapy-associated effects, functional polymorphisms in the TP53 and MDM2 genes could influence the response to treatment and the prognosis following CRT. We investigated associations between two such polymorphisms, and p53 overexpression, and response or survival in bladder cancer patients treated with CRT. The study group comprised 96 patients who underwent CRT for transitional cell carcinoma of the bladder. Single nucleotide polymorphisms (SNPs) in TP53 (codon 72, arginine > proline) and MDM2 (SNP309, T > G) were genotyped using PCR-RFLP, and nuclear expression levels of p53 were examined using immunohistochemistry. None of the genotypes or p53 overexpression was significantly associated with response to CRT. However, patients with MDM2 T / G + G / G genotypes had improved cancer-specific survival rates after CRT (P = 0.009). In multivariate analysis, the MDM2 T / G + G / G genotypes, and more than two of total variant alleles in TP53 and MDM2, were independently associated with improved cancer-specific survival (P = 0.031 and P = 0.015, respectively). In addition, MDM2 genotypes were significantly associated with cystectomy-free survival (P = 0.030). These results suggest that the TP53 and MDM2 genotypes might be useful prognostic factors following CRT in bladder cancer, helping patient selection for bladder conservation therapy.

Molecular epidemiology of DNA repair genes in bladder cancer

Bladder cancer is a common disease, whose major risk factors include smoking and occupational exposure to chemicals. Superficial bladder cancer has significant healthcare cost implications due to the need for repeated cystoscopic surveillance. Chemical carcinogens can undergo metabolic activation and detoxification in the liver and polymorphisms in the relevant genes have been shown to be associated with bladder cancer risk. In addition, DNA repair enzymes are required to repair the DNA damage associated with carcinogen exposure. The main pathways involved are nucleotide excision repair, base excision repair, and double strand break repair. Investigation of individual polymorphisms in DNA repair genes in bladder cancer has yielded few robust positive findings, which is not surprising given the multifactorial nature of the disease. Pathway approaches using novel genotyping technologies will allow more comprehensive studies of multiple polymorphisms in multiple genes. It will also be possible to investigate gene-environment interaction more rigorously than heretofore, using novel statistical methodology, in larger studies and through collaborative efforts within consortia. The results of the genome-wide association studies in bladder cancer are awaited with interest. In the future, genetic tests might be used in the prevention of bladder cancer to encourage lifestyle changes in those at highest risk of developing the disease, and in the treatment of bladder cancer to optimise cure rates whilst minimising morbidity in a cost-effective manner.

DNA repair gene polymorphisms may be associated with prognosis of upper urinary tract transitional cell carcinoma

Upper urinary tract transitional cell carcinoma (UUT-TCC) is quite an uncommon disease, and its prognosis differs among individuals irrespective of tumor stage. DNA repair gene polymorphisms are reported to result in the modulation of the repair capacity and might influence the prognosis of UUT-TCC. We examined the associations between functional polymorphisms in five DNA repair genes, and the prognosis of UUT-TCC in 103 UUT-TCC patients. Variant alleles in xeroderma pigmentosum complementation group C, more than three total variant alleles in all DNA repair genes studied and more than two total variant alleles in three nucleotide excision repair genes were independently associated with improved overall and disease-specific survival of UUT-TCC patients in multivariate analysis (P = .0063 and P = .0005 for xeroderma pigmentosum complementation group C, P = .016 and P = .0016 for all genes, and P = .0053 and P = .018 for nucleotide excision repair genes, respectively). These results suggest that some DNA repair gene polymorphisms may preoperatively be valuable as prognostic factors for UUT-TCC beyond tumor stage and grade, helping to provide optimal treatment strategies for individual patients.

The association of DNA repair gene polymorphisms with the development and progression of renal cell carcinoma

BACKGROUND

DNA repair enzymes repair some of the DNA damage associated with risk factors for renal cell carcinoma (RCC), including smoking. DNA repair gene polymorphisms modulate the repair capacity and might influence individual risk and progression of RCC. We examined associations between functional polymorphisms and risk, clinicopathologic characteristics and survival of RCC.

PATIENTS AND METHODS

The study groups comprised 215 RCC patients and 215 age- and gender-matched healthy controls. Polymorphisms in xeroderma pigmentosum complementation groups C, D and G and X-ray repair cross-complementing groups 1 and 3 genes were genotyped.

RESULTS

No significant differences in DNA repair genotype were observed between RCC cases and controls. In all patients, however, greater numbers (> or =3) of total variant alleles in all DNA repair genes studied were associated with less frequent venous extension (P = 0.0079). In smokers, some genotypes were associated with characteristics of RCC (Ps < or = 0.0067) and smokers with greater numbers of total variant alleles had improved overall survival (P = 0.040).

CONCLUSION

These results suggest that DNA repair gene polymorphisms may not influence RCC susceptibility, but that some of them may influence RCC progression, especially in smokers, possibly due to altered DNA repair capacity by these polymorphisms.

Association between DNA Repair Gene Polymorphisms and p53 Alterations in Japanese Patients with Muscle-Invasive Bladder Cancer

OBJECTIVE

DNA repair enzymes play a vital role in protecting the genome from carcinogens, several of which can cause mutations in the TP53 gene in bladder cancer. Some single nucleotide polymorphisms (SNPs) in DNA repair genes reportedly modulate the repair capacity. This study aimed to clarify the effect of these functional SNPs on the alteration of p53 in muscle-invasive bladder cancer.

METHODS

We investigated the association between SNPs in xeroderma pigmentosum complementation groups C (XPC), D and G and X-ray repair cross-complementing group 1 and 3 genes, and p53 expression and allelic imbalance at the TP53 locus in Japanese patients with muscle-invasive bladder cancer. p53 expression and the allelic imbalance were evaluated using immunohistochemistry and a microsatellite marker, respectively.

RESULTS

Positive p53 expression was significantly less frequent in patients with the CC genotype of the XPC gene than in those with the AA or AC genotype (p = 0.0005). C alleles of the XPC gene were also less frequent in patients with positive p53 expression (p = 0.01).

CONCLUSION

Our results suggested that the XPC polymorphism might affect p53 alteration and the molecular pathway defined by the p53 alteration in the development of muscle-invasive bladder cancer.

Associations of single nucleotide polymorphisms in the vascular endothelial growth factor gene with the characteristics and prognosis of renal cell carcinomas

OBJECTIVES

Vascular endothelial growth factor (VEGF) is considered to play critical roles in tumor development and progression, especially in renal cell carcinoma (RCC) via von Hippel-Lindau gene inactivation. Although VEGF -2578CC, -1154GG, and -634CC genotypes are reportedly correlated with higher levels of VEGF production, no previous studies have reported on the associations of these polymorphisms with RCCs. This study was aimed to clarify the effects of these functional polymorphisms on RCC progression and prognosis.

METHODS

We investigated the associations of three polymorphisms (-2578C/A, -1154G/A, and -634C/G) in the VEGF gene with the clinicopathologic parameters and survival of 213 patients with RCC. The -2578C/A and -634C/G polymorphisms were genotyped using a polymerase chain reaction (PCR) restriction fragment length polymorphism technique and the -1154G/A polymorphism was genotyped by an amplification refractory mutation system PCR technique.

RESULTS

The GA+AA genotypes of -1154G/A were weakly associated with smaller tumors, lower tumor stage, and lower stage grouping (p=0.028, p=0.012, and p=0.028, respectively). The CA and CA+AA genotypes of -2578C/A were weakly associated with less frequent lymph node metastasis (p=0.029 and p=0.034, respectively) and were significantly associated with favorable cancer-specific survival (p=0.047 and p=0.048, respectively). There was no apparent clinical effect of the -634C/G polymorphism.

CONCLUSIONS

These results suggest that some VEGF genotypes may have effects on RCC progression or prognosis, possibly through altered VEGF expression. This finding might help in clarifying the mechanisms of RCC development and progression.

Single nucleotide polymorphisms in DNA repair genes might be prognostic factors in muscle-invasive bladder cancer patients treated with chemoradiotherapy

DNA repair enzymes repair DNA damaged by platinum agents and ionising radiation. Single nucleotide polymorphisms (SNPs) in DNA repair genes modulate the repair capacity and might affect response and prognosis following platinum-based chemoradiotherapy (CRT). We investigated associations between the functional SNPs in DNA repair genes and response and survival in muscle-invasive bladder cancer patients treated with CRT to determine the predictive value of the SNPs in patient selection for bladder conservation therapy. The study group comprised 78 patients who underwent CRT for transitional cell carcinoma of the bladder. Single nucleotide polymorphisms in xeroderma pigmentosum complementation groups C (Lys939Gln, A/C), D (XPD; Lys751Gln, A/C), and G (Asp1104His, G/C), and X-ray repair cross-complementing groups 1 (XRCC1; Arg399Gln, G/A) and 3 (Thr241Met, T/C) genes were genotyped. Combined genotypes with at least one variant allele in XPD or XRCC1 were significantly associated with improved cancer-specific survival compared with remaining groups (P=0.009). In multivariate analysis, only the combined XPD and XRCC1 genotypes were independently associated with cancer-specific survival (P=0.04). The association was stronger in stage T3/T4 patients (P=0.0008). These results suggest that combined XPD and XRCC1 genotypes might be prognostic factors in muscle-invasive bladder cancer patients treated with CRT.