Impact of nucleotide excision repair ERCC2 and base excision repair APEX1 genes polymorphism and its association with recurrence after adjuvant BCG immunotherapy in bladder cancer patients of North India

Impact of smoking exposure on disease progression in high risk and very high-risk nonmuscle invasive bladder cancer patients undergoing BCG therapy

INTRODUCTION

The nonmuscle invasive bladder cancer treated with BCG instillations in patients who smoke could potentially lead to poorer oncological results in the light of the new EAU risk groups classification for NMIBC that did not include BCG treated patients or smoking status.

PATIENT AND METHODS

Outcomes from 1313 patients with nonmuscle invasive bladder cancer treated with TURBT, re-TURBT and BCG instillations at 13 academic hospital centers, since 2002, has been included in this retrospective study. The study variables, including cumulative smoking exposure have been analyzed. A multivariable Cox proportional hazard model was used to assess associations between smoking variables and disease progression and repeated in the EAU high risk and very high-risk group. The statistical significance threshold was set at 0.05, and the statistical analysis was performed using Stata/SE version 17 (StataCorp, College Station, TX, USA).

RESULTS

Cox regression analysis revealed in 1313 patients diagnosed with T1G3 NMIBC that patients with a history of heavy and long-term smoking faced a more than twofold increased risk of disease progression compared to nonsmoker patients (HR 2.35; 95% CI: 1.7-3.2; P < 0.01) and a significantly poorer PFS for patients with a history of heavy long-term smoke exposure (P < 0.01). Patients with heavy long-term smoking exposure according to the EAU21 high-risk group had a PFS comparable to very high-risk patients and high-risk patients with heavy long-term smoking exposure showed a higher risk of progression when compared to the high-risk group (HR 1.4; 95% CI: 1.3-1.6; P < 0.01).

CONCLUSIONS

This study adds valuable information on the relationship between smoking and the progression of NMIBC and BCG therapy. The findings emphasize the need for healthcare providers to consider a patient's smoking history when managing NMIBC and express the need for individualized smoking cessation counseling and individualized treatment approach.

The impact of smoking on recurrence and progression of non-muscle invasive bladder cancer: a systematic review and meta-analysis

OBJECTIVES

Although smoking is a well-recognized causative factor of urothelial bladder cancer and accounts for 50% of cases, less is known about the prognostic significance of smoking on non-muscle invasive bladder cancer (NMIBC) prognosis. This systematic review and meta-analysis aimed to evaluate the effect of smoking on the risk of NMIBC recurrence and progression.

MATERIALS AND METHODS

We systematically searched Medline, Web of Science and Scopus databases for original articles published before October 2021 regarding the effect of smoking on NMIBC recurrence and progression. Information about smoking status and the number of events or odds ratio or hazard ratio for event-free survival must have been reported to include the study in the analysis. Quality In Prognosis Studies tool was utilized for the risk of bias assessment.

RESULTS

We selected 64 eligible studies, including 28 617 patients with NMIBC with available data on smoking status. In a meta-analysis of 28 studies with 7885 patients, we found that smokers (current/former) were at higher risk for recurrence (OR = 1.68; 95% CI 1.34-2.09; P < 0.0001) compared to never smokers. Subgroup analysis of 2967 patients revealed that current smokers were at a 1.24 higher risk of recurrence (OR = 1.24; 95% CI 1.02-1.50; P = 0.03) compared to former smokers. A meta-analysis of the hazard ratio revealed that smokers are at higher risk of recurrence (HR = 1.31; 95%CI 1.15-1.48; P < 0.0001) and progression (HR = 1.18; 95%CI 1.08-1.29; P < 0.001) compared to never smokers. Detrimental prognostic effect of smoking on progression, but not for recurrence risk was also noted in the subgroup analysis of high-risk patients (HR = 1.30; 95%CI 1.09-1.55; P = 0.004) and BCG-treated ones (HR = 1.15; 95%CI 1.06-1.25; P < 0.001).

CONCLUSION

In conclusion, patients with non-muscle invasive bladder cancer and a history of smoking have a worse prognosis regarding recurrence-free and progression-free survival compared to non-smokers.

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.

DNA Repair Molecular Beacon assay: a platform for real-time functional analysis of cellular DNA repair capacity

Numerous studies have shown that select DNA repair enzyme activities impact response and/or toxicity of genotoxins, suggesting a requirement for enzyme functional analyses to bolster precision medicine or prevention. To address this need, we developed a DNA Repair Molecular Beacon (DRMB) platform that rapidly measures DNA repair enzyme activity in real-time. The DRMB assay is applicable for discovery of DNA repair enzyme inhibitors, for the quantification of enzyme rates and is sufficiently sensitive to differentiate cellular enzymatic activity that stems from variation in expression or effects of amino acid substitutions. We show activity measures of several different base excision repair (BER) enzymes, including proteins with tumor-identified point mutations, revealing lesion-, lesion-context- and cell-type-specific repair dependence; suggesting application for DNA repair capacity analysis of tumors. DRMB measurements using lysates from isogenic control and APE1-deficient human cells suggests the major mechanism of base lesion removal by most DNA glycosylases may be mono-functional base hydrolysis. In addition, development of a microbead-conjugated DRMB assay amenable to flow cytometric analysis further advances its application. Our studies establish an analytical platform capable of evaluating the enzyme activity of select DNA repair proteins in an effort to design and guide inhibitor development and precision cancer therapy options.

Modulation of Colorectal Cancer Risk by Polymorphisms in 51Gln/His, 64Ile/Val, and 148Asp/Glu of APEX Gene; 23Gly/Ala of XPA Gene; and 689Ser/Arg of ERCC4 Gene

Polymorphisms in DNA repair genes may affect the activity of the BER (base excision repair) and NER (nucleotide excision repair) systems. Using DNA isolated from blood taken from patients (n = 312) and a control group (n = 320) with CRC, we have analyzed the polymorphisms of selected DNA repair genes and we have demonstrated that genotypes 51Gln/His and 148Asp/Glu of APEX gene and 23Gly/Ala of XPA gene may increase the risk of colorectal cancer. At the same time analyzing the gene-gene interactions, we suggest the thesis that the main factor to be considered when analyzing the impact of polymorphisms on the risk of malignant transformation should be intergenic interactions. Moreover, we are suggesting that some polymorphisms may have impact not only on the malignant transformation but also on the stage of the tumor.

Prediction of Bacillus Calmette-Guerin Response in Patients with Bladder Cancer after Transurethral Resection of Bladder Tumor by Using Genetic Variation Based on Genomic Studies

Purpose. We aimed to comprehensively review contemporary literature on genetic and epigenetic biomarkers associated with the prediction of Bacillus Calmette-Guerin (BCG) response after the transurethral resection of a bladder tumor and to discuss the application of these biomarkers in precision cancer care for bladder cancer. Method. We performed a systematic review of published literatures in the databases PubMed and Embase by using the following key words: bladder cancer, BCG, gene, and methylation. Studies associated with cell lines, animal models, and muscle invasive bladder cancer were excluded. Results. The genetic variations associated with BCG response can be classified into three categories: germline variations, somatic variations, and epigenetic alterations. Genes related to BCG response were mainly involved in single-nucleotide polymorphisms, copy number variations, and gene methylations. Conclusions. Although these gene alterations are currently the most promising predictive markers of BCG response, most studies about bladder cancer DNA biomarkers are related to germline variations in candidate genes, and the results are not consistent. Only one study is related to somatic variation, and further evaluation in large-scale validation studies should be conducted to assess the potential clinical application of these findings. In addition, other biomarkers based on different “–omics” technologies should be considered in future studies.

Independent Replication of Published Germline Polymorphisms Associated with Urinary Bladder Cancer Prognosis and Treatment Response

BACKGROUND

Many studies investigated the prognostic or predictive relevance of single nucleotide polymorphisms (SNPs) in biologically plausible genes in urinary bladder cancer (UBC) patients. Most published SNP associations have never been replicated in independent patient series.

OBJECTIVE

To independently replicate all previously reported associations between germline SNPs and disease prognosis or treatment response in UBC.

METHODS

A Pubmed search was performed to identify studies published by July 1, 2014 reporting on germline SNP associations with UBC prognosis or treatment response. For the replication series, consisting of 1,284 non-muscle-invasive bladder cancer (NMIBC) and 275 muscle-invasive or metastatic bladder cancer (MIBC) patients recruited through the Netherlands Cancer Registry, detailed clinical data were retrieved from medical charts. Patients were genotyped using a genome-wide SNP array. SNP association with recurrence-free, progression-free, and overall survival (OS) within specific patient and treatment strata was tested using Cox regression analyses.

RESULTS

For only six of the 114 evaluated SNPs, the association with either UBC prognosis or treatment response was replicated at the p <  0.05 level: rs1799793 (ERCC2) and rs187238 (IL18) for BCG recurrence; rs6678136 (RGS4) and rs11585883 (RGS5) for NMIBC progression; rs12035879 (RGS5) and rs2075786 (TERT) for MIBC OS.

CONCLUSIONS

Non-replicated genetic associations in the literature require cautious interpretation. This single replication does not provide definitive proof of association for the six SNPs, and non-replication of other SNPs may result from population-specific effects or the retrospective patient enrollment.

Significant Role of Lifetime Cigarette Smoking in Worsening Bladder Cancer and Upper Tract Urothelial Carcinoma Prognosis: A Meta-Analysis

PURPOSE

Although cigarette smoking is a well established risk factor for urothelial cancer, its role in urothelial cancer prognosis is still undetermined. In this meta-analysis we quantify the role of lifetime smoking history in bladder cancer recurrence, progression and survival by pooling available data on nonmuscle invasive bladder cancer, muscle invasive bladder cancer and upper tract urothelial carcinoma.

MATERIALS AND METHODS

A total of 24 studies, comprising data from 13,114 patients with bladder cancer and 2,259 patients with upper tract urothelial carcinoma, were included in this meta-analysis. Publication bias was addressed through Egger's test, and the heterogeneity among studies was assessed by the I(2) test statistic and subgroup analyses.

RESULTS

Current smokers at diagnosis are at increased risk for local recurrence in nonmuscle invasive bladder cancer (HR 1.27, 95% CI 1.09-1.46) and smokers with muscle invasive bladder cancer have an increased risk of dying of bladder cancer (HR 1.23, 95% CI 1.02-1.44). In the upper tract urothelial carcinoma population smokers have an increased risk of recurrence in the operative bed (HR 1.57, 95% CI 1.19-1.95) and of death from upper tract urothelial carcinoma (HR 1.53, 95% CI 1.13-1.92). We did not identify significant heterogeneity among included studies.

CONCLUSIONS

The body of evidence is limited due to the absence of prospective studies. However, the results from this meta-analysis unambiguously support the hypothesis that lifetime cigarette smokers are at increased risk for a more malignant type of urothelial carcinoma associated with a worse prognosis.

Outcome after BCG treatment for urinary bladder cancer may be influenced by polymorphisms in the NOS2 and NOS3 genes

Purpose

Bacillus Calmette-Guérin (BCG)-treatment is an established treatment for bladder cancer, but its mechanisms of action are not fully understood. High-risk non-muscle invasive bladder-cancer (NMIBC)-patients failing to respond to BCG-treatment have worse prognosis than those undergoing immediate radical cystectomy and identification of patients at risk for BCG-failure is of high priority. Several studies indicate a role for nitric oxide (NO) in the cytotoxic effect that BCG exerts on bladder cancer cells. In this study we investigated whether NO-synthase (NOS)-gene polymorphisms, NOS2-promoter microsatellite (CCTTT)n, and the NOS3-polymorphisms-786T>C (rs2070744) and Glu298Asp (rs1799983), can serve as possible molecular markers for outcome after BCG-treatment for NMIBC.

Materials and methods

All NMIBC-patients from a well-characterized population based cohort were analyzed (n=88). Polymorphism data were combined with information from 15-years of clinical follow-up. The effect of BCG-treatment on cancer-specific death (CSD), recurrence and progression in patients with varying NOS-genotypes were studied using Cox proportional hazard-models and log rank tests.

Results

BCG-treatment resulted in significantly better survival in patients without (Log rank: p=0.006; HR: 0.12, p=0.048), but not in patients with a long version ((CCTTT)n ≧13 repeats) of the NOS2-promoter microsatellite. The NOS3-rs2070744(TT) and rs1799983(GG)-genotypes showed decreased risk for CSD (Log rank(TT): p=0.001; Log rank(GG): p=0.010, HR(GG): 0.16, p=0.030) and progression (Log rank(TT): p<0.001, HR(TT): 0.05, p=0.005; Log rank(GG): p<0.001, HR(GG): 0.10, p=0.003) after BCG-therapy compared to the other genotypes. There was also a reduction in recurrence in BCG-treated patients that was mostly genotype independent. Analysis of combined genotypes identified a subgroup of 30% of the BCG-treated patients that did not benefit from BCG-treatment.

Conclusions

Our results suggest that the investigated polymorphisms influence patient response to BCG-treatment and thus may serve as possible markers for identification of BCG-failures.

•

30% of BCG treated bladder cancer (NMIBC)-patients do not respond to BCG-treatment.

•

We need to identify BCG failures before the BCG-treatment is given.

•

Altered NOS2 and NOS3 gene activity may be associated with BCG treatment outcome.

•

NOS-polymorphisms are possible BCG-failure biomarkers in bladder cancer patients.

Inter-individual variation in DNA repair capacity: a need for multi-pathway functional assays to promote translational DNA repair research

Why does a constant barrage of DNA damage lead to disease in some individuals, while others remain healthy? This article surveys current work addressing the implications of inter-individual variation in DNA repair capacity for human health, and discusses the status of DNA repair assays as potential clinical tools for personalized prevention or treatment of disease. In particular, we highlight research showing that there are significant inter-individual variations in DNA repair capacity (DRC), and that measuring these differences provides important biological insight regarding disease susceptibility and cancer treatment efficacy. We emphasize work showing that it is important to measure repair capacity in multiple pathways, and that functional assays are required to fill a gap left by genome wide association studies, global gene expression and proteomics. Finally, we discuss research that will be needed to overcome barriers that currently limit the use of DNA repair assays in the clinic.

The predictive value of GSTT1 polymorphisms in predicting the early response to induction BCG therapy in patients with non-muscle invasive bladder cancer

INTRODUCTION

We evaluated the predictive value of glutathione S transferase mu (GSTM1) and theta (GSTT1) polymorphisms in early response to bacillus Calmette-Guérin (BCG) induction therapy in patients with primary non-muscle invasive bladder cancer.

METHODS

GSTM1 and GSTT1 polymorphisms were analyzed by multiplex polymerase chain reaction using blood genomic DNA from 135 patients with primary non-muscle invasive bladder cancer who were being treated with a single induction course of BCG. BCG nonresponsiveness (early BCG failure) was defined as a tumor recurrence or progression within 12 months after BCG induction therapy. The predictive value of GST polymorphisms was evaluated by Kaplan-Meier analysis and multivariate logistic regression models.

RESULTS

Patients carrying a GSTT1-positive genotype demonstrated a higher likelihood of early BCG failure regardless of cigarette smoking. After stratification based on the tumor stage and grade, the high-risk group (T1G3) with a GSTT1-positive genotype showed a 14-fold higher risk of early BCG failure compared with those with a GSTT1-null genotype. In a combined analysis of 2 genes, the GSTT1-positive/GSTM1-null genotype had a higher risk of BCG nonresponsiveness compared with the GSTT1-null/GSTM1-null genotype (odds ratio = 4.17, 95% CI: 1.54-11.26). By multivariate logistic regression analysis, the GSTT1-positive genotype was an independent predictor of early BCG failure (odds ratio = 3.67, 95% CI: 1.61-8.38). Kaplan-Meier estimates revealed a significant difference in disease-free survival depending on the GSTT1 genotype (log rank test, P = 0.038).

CONCLUSIONS

The results of this study suggest that the GSTT1-positive genotype is an independent predictor of early BCG failure. These results can help determine whether patients would benefit from adjuvant BCG treatment or may require more aggressive alternative therapies.

Effect of smoking on outcomes of urothelial carcinoma: a systematic review of the literature

CONTEXT

Cigarette smoking is the best-established risk factor for urothelial carcinoma (UC). However, the effect of smoking on outcomes of UC patients remains debated.

OBJECTIVE

To integrate the available evidence regarding the impact of smoking status and smoking exposure on recurrence, progression, cancer-specific mortality, and any-cause mortality in patients with UC of the bladder (UCB) and upper tract UC (UTUC) treated with transurethral resection of the bladder (TURB), radical cystectomy (RC), or radical nephroureterectomy (RNU).

EVIDENCE ACQUISITION

A systematic search of the literature was conducted using the Medline, Embase, and Scopus databases, which was limited to articles published in English between January 1974 and March 2013. Articles were also extracted from the reference lists of identified studies and reviews. We selected 29 articles (15 TURB, 7 RC, and 7 RNU) according to predefined inclusion criteria and the Preferred Reporting Items for Systematic Reviews and Meta-analyses.

EVIDENCE SYNTHESIS

The majority of studies demonstrated an association with disease recurrence in patients treated with TURB, while evidence for associations with disease progression, cancer-specific mortality, and any-cause mortality was less abundant. While two studies showed no association of smoking with outcomes of T1 UCB, there was mixed evidence for an association of smoking with response to intravesical therapy. For patients treated with RC, there was minimal support for an association of smoking with all outcomes. In a majority of studies of patients receiving RNU for UTUC, smoking was associated with intravesical recurrence, disease recurrence, cancer-specific mortality, and any-cause mortality. There was also evidence for a beneficial effect of smoking cessation on UC prognosis. Finally, findings regarding gender-specific effects of smoking on prognosis were contradictory. We note that there was marked heterogeneity in patient populations and smoking categorizations across studies, precluding a meta-analysis.

CONCLUSIONS

Smoking may lead to less favorable outcomes for UCB and UTUC patients, and smoking cessation may mitigate this effect. The current evidence base lacks studies on the effects of smoking on prognosis in numerous clinical demographic subgroups of UC patients, as well as prospective investigation of smoking cessation.

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.

Predictive biomarkers of bacillus calmette-guérin immunotherapy response in bladder cancer: where are we now?

The most effective therapeutic option for managing nonmuscle invasive bladder cancer (NMIBC), over the last 30 years, consists of intravesical instillations with the attenuated strain Bacillus Calmette-Guérin (the BCG vaccine). This has been performed as an adjuvant therapeutic to transurethral resection of bladder tumour (TURBT) and mostly directed towards patients with high-grade tumours, T1 tumours, and in situ carcinomas. However, from 20% to 40% of the patients do not respond and frequently present tumour progression. Since BCG effectiveness is unpredictable, it is important to find consistent biomarkers that can aid either in the prediction of the outcome and/or side effects development. Accordingly, we conducted a systematic critical review to identify the most preeminent predictive molecular markers associated with BCG response. To the best of our knowledge, this is the first review exclusively focusing on predictive biomarkers for BCG treatment outcome. Using a specific query, 1324 abstracts were gathered, then inclusion/exclusion criteria were applied, and finally 87 manuscripts were included. Several molecules, including CD68 and genetic polymorphisms, have been identified as promising surrogate biomarkers. Combinatory analysis of the candidate predictive markers is a crucial step to create a predictive profile of treatment response.

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.

Susceptibility of XPD and RAD51 genetic variants to carcinoma of urinary bladder in North Indian population

For the present study, two polymorphisms, xeroderma pigmentosum, complementation group D (XPD) Lys751Gln and RAD51 135G/C were studied with regard to bladder cancer. For XPD Lys751Gln polymorphism, an increased risk of bladder cancer was found to be associated with the Gln variant allele (odds ratio [OR]=1.86, 95% confidence interval [CI]=1.27-2.73), on taking AA (Lys/Lys) as the referent genotype. In males, the XPD 751C (Gln) allele was found to be associated with a significantly increased risk (OR=2.33, 95% CI=1.52-3.56). The inhabitants of rural areas showed a significantly increased risk with the XPD Gln allele (OR=2.59, 95% CI=1.46-4.62) when compared with those of urban areas. In smokers (OR=5.30, 95% CI=2.42-11.68), alcohol drinkers (OR=4.33, 95% CI=2.17-8.70), and nonvegetarians (OR=2.21, 95% CI=1.26-3.87), the XPD Gln allele showed a significantly increased risk toward bladder cancer. For RAD51 135G/C polymorphism, no significant difference was observed in the allelic and genotypic frequencies. Even after stratification, no significant association could be seen. After stratifying histopathologically, the RAD51 CC genotype was associted with decreased risk in subjects having superficial stage (OR=0.51, 95% CI=0.27-0.99) and with those having G2 grade (OR=0.24, 95% CI=0.09-0.62) of bladder cancer. XPD polymorphism may be a predisposing factor, but the same cannot be said for RAD51 gene polymorphism.

Genetic variants in DNA repair predicts the survival of patients with esophageal cancer

OBJECTIVE

To investigate the association of the genetic variants in excision repair cross-complementation group 2 (ERCC2) R156R and ERCC4 rs3136038 with survival duration for patients with esophageal cancer.

BACKGROUND

ERCC2 and ERCC4 are important molecules participating nucleotide excision repair system. The clinical relevance of the genetic variants of these genes is largely unknown currently.

PATIENTS AND METHODS

A total of 400 patients with a diagnosis of esophageal cancer were included. The genetic variants in the promoter regions of ERCC2 on R156R and ERCC4 on rs3136038 were analyzed with the TaqMan assay from leukocyte DNA collected before treatment and correlated to survival of the patients.

RESULTS

Presence with ERCC2 R156R C/C or ERCC4 rs3136038 C/T genotype of the patients could additively increase risk of death and disease progression. Under multivariate analysis, T, N staging and simultaneous presentation of these unfavorable genotypes were found significant for prognosis (P < 0.05). Accumulation of each unfavorable genotype would associate with adjusted HRs [95% CI] of 1.35 [1.10-1.65] and 1.37 [1.12-1.68] (P ≤ 0.05) for death and disease progression respectively. The prognostic impact of these genotypes were more evident in the subgroup of patients with early disease status including T staging (II or less), free from lymph node metastasis or being able to undergo surgical resection (P < 0.05 for both overall and disease progression-free survival duration, respectively).

CONCLUSION

Genetic variants in ERCC2 and ERCC4 may provide further survival prediction in addition to TNM staging system of esophageal cancer, which is more evident in the patients with early disease status.

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.