The association between NQO1 Pro187Ser polymorphism and bladder cancer susceptibility: a meta-analysis of 15 studies

XPC as breast cancer susceptibility gene: evidence from genetic profiling, statistical inferences and protein structural analysis

BACKGROUND

Gene polymorphisms that affect nucleotide excision repair (NER) pathway may link with higher susceptibility of breast cancer (BC); however, the significance of these associations may vary conferring to the individual ethnicity. Xeroderma pigmentosum complementation gene (XPC) plays a substantial role in recognizing damaged DNA during NER process.

OBJECTIVE AND METHODS

To estimate the relationship among XPC polymorphisms and breast cancer (BC) risk, we carried out a case-control-association study with 493 BC cases and 387 controls using TETRA-ARMS-PCR. Distributional differences of clinical features, demographic factors and XPC polymorphisms among BC cases and controls were examined by conditional logistic regression model. Kaplan-Meier test was applied to predict survival distributions and protein structure was predicted using computational tools.

RESULTS

Obesity, consanguinity, positive marital status and BC family history were associated (P ≤ 0.01) with higher BC risk. Genotyping revealed significant involvement (P ≤ 0.01) of two XPC polymorphisms rs2228001-A > C (OR = 3.8; CI 1.9-7.6) and rs2733532-C > T (OR = 2.6; CI 1.4-5.03) in BC development, asserting them potential risk factors for increased BC incidence. However, no association (P > 0.05) was detected for overall or progression free survival for both XPC polymorphisms possibly due to shorter follow-up time (45 months). As compared to normal XPC structure, pronounced conformational changes have been observed in the C-terminus of XPC^Q939K, bearing rs2228001-A > C substitution. In XPC^Q939K, two additional α-helices were observed at A292-E297 and Y252-R286, while L623-M630 and L649-L653 helices were converted into loop conformation.

CONCLUSION

In conclusion, both XPC polymorphisms confer significant association with increased BC risk. rs2228001 substitution may change the structural and functional preferences of XPC C-terminus, while rs2733532 may have regulatory role thereby leading to potential BC risk.

Inherited alterations of TGF beta signaling components in Appalachian cervical cancers

PURPOSE

This study examined targeted genomic variants of transforming growth factor beta (TGFB) signaling in Appalachian women. Appalachian women with cervical cancer were compared to healthy Appalachian counterparts to determine whether these polymorphic alleles were over-represented within this high-risk cancer population, and whether lifestyle or environmental factors modified the aggregate genetic risk in these Appalachian women.

METHODS

Appalachian women's survey data and blood samples from the Community Awareness, Resources, and Education (CARE) CARE I and CARE II studies (n = 163 invasive cervical cancer cases, 842 controls) were used to assess gene-environment interactions and cancer risk. Polymorphic allele frequencies and socio-behavioral demographic measurements were compared using t tests and χ2 tests. Multivariable logistic regression was used to evaluate interaction effects between genomic variance and demographic, behavioral, and environmental characteristics.

RESULTS

Several alleles demonstrated significant interaction with smoking (TP53 rs1042522, TGFB1 rs1800469), alcohol consumption (NQO1 rs1800566), and sexual intercourse before the age of 18 (TGFBR1 rs11466445, TGFBR1 rs7034462, TGFBR1 rs11568785). Interestingly, we noted a significant interaction between "Appalachian self-identity" variables and NQO1 rs1800566. Multivariable logistic regression of cancer status in an over-dominant TGFB1 rs1800469/TGFBR1 rs11568785 model demonstrated a 3.03-fold reduction in cervical cancer odds. Similar decreased odds (2.78-fold) were observed in an over-dominant TGFB1 rs1800469/TGFBR1 rs7034462 model in subjects who had no sexual intercourse before age 18.

CONCLUSIONS

This study reports novel associations between common low-penetrance alleles in the TGFB signaling cascade and modified risk of cervical cancer in Appalachian women. Furthermore, our unexpected findings associating Appalachian identity and NQO1 rs1800566 suggests that the complex environmental exposures that contribute to Appalachian self-identity in Appalachian cervical cancer patients represent an emerging avenue of scientific exploration.

Bladder Cancer Genetic Susceptibility. A Systematic Review

Background:

The variant/gene candidate approach to explore bladder cancer (BC) genetic susceptibility has been applied in many studies with significant findings reported. However, results are not always conclusive due to the lack of replication by subsequent studies.

Objectives:

To identify all epidemiological investigations on the genetic associations with BC risk, to quantify the likely magnitude of the associations by applying metaanalysis methodology and to assess whether there is a potential for publication/reporting bias.

Methods:

To address our aims, we have catalogued all genetic association studies published in the field of BC risk since 2000. Furthermore, we metaanalysed all polymorphisms with data available from at least three independent case-control studies with subjects of Caucasian origin analyzed under the same mode of inheritance.

Results:

The characterization of the genetic susceptibility of BC is composed of 28 variants, GWAS contributing most of them. Most of the significant variants associated with BC risk are located in genes belonging to chemical carcinogenesis, DNA repair, and cell cycle pathways. Causal relationship was also provided by functional analysis for GSTM1-null, NAT2-slow, APOBEC-rs1014971, CCNE1-rs8102137, SLC14A1-rs10775480, PSCA-rs2294008, UGT1A-rs1189203, and TP63-rs35592567.

Conclusions:

Genetic susceptibility of BC is still poorly defined, with GWAS contributing most of the strongest evidence. The systematic review did not provide evidence of further genetic associations. The potential public health translation of the existing knowledge on genetic susceptibility on BC is still limited.

NQO1 C609T polymorphism and lung cancer susceptibility: Evidence from a comprehensive meta-analysis

A variety of case-control studies have been performed to assess the correlation between NQO1 C609T polymorphism and the risk of lung cancer, but an explicit consensus has not been reached. We conducted this updated meta-analysis to identify the function of NQO1 C609T polymorphism in lung cancer risk. All relevant literature was retrieved from the PubMed, EMBASE, CNKI, and WanFang databases before April 2017. A total of 37 studies (29 articles) with 8493 cases and 10,999 controls were included. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of relations. We found that the NQO1 C609T polymorphism did not correlate with the risk of lung cancer in the overall analysis. In addition, no statistical significance was observed in the analysis stratified based on ethnicity, control source, quality score, or smoking status. A significant association was found in the subgroup of small cell lung cancer risk. Despite some limitations, this meta-analysis indicates that the NQO1 C609T polymorphism may not be associated with lung cancer risk. However, more epidemiological studies of larger samples and more ethnicities are needed to confirm these results.

State of Art of Cancer Pharmacogenomics in Latin American Populations

Over the past decades, several studies have shown that tumor-related somatic and germline alterations predicts tumor prognosis, drug response and toxicity. Latin American populations present a vast geno-phenotypic diversity due to the great interethnic and interracial mixing. This genetic flow leads to the appearance of complex characteristics that allow individuals to adapt to endemic environments, such as high altitude or extreme tropical weather. These genetic changes, most of them subtle and unexplored, could establish a mutational profile to develop new pharmacogenomic therapies specific for Latin American populations. In this review, we present the current status of research on somatic and germline alterations in Latin America compared to those found in Caucasian and Asian populations.

Short-term Exposure to 50-Hz Electromagnetic Field and Alterations in NQO1 and NQO2 Expression in MCF-7 Cells

AIM:

Extremely low-frequency electromagnetic fields (ELF-EMFs) have some genotoxic effects and it may alter the mRNA levels of antioxidant genes. The NAD(P)H: quinone oxidoreductase-1 (NQO1) and NQO2 are ubiquitously expressed. Considering that there is no published data on the effect(s) of ELF-EMF (50-Hz) exposure and expression levels of NQO1 and NQO2 in the human MCF-7 cells, the present study was carried out.

METHODS:

The ELF-EMF (0.25 and 0.50 mT) exposure patterns were: 5 min field-on/5 min filed-off, 15 min field-on/15 min field-off, and 30 min field-on continuously. In all exposure conditions, total exposure time were 30 minutes. The RNA extraction was done at two times; immediately post exposure and two hours post exposure. The effect of ELF-EMF on gene expression was assessed by real-time PCR.

RESULTS:

The NQO1 mRNA level (at 0h) decreased in the cells exposed to 5 min field-on/5 min filed-off condition at 0.25 mT EMF when compared with the unexposed cells. The NQO2 mRNA level (at 0h and 2h) increased in the cells exposed to 5 min field-on/5 min filed-off condition at 0.50 mT EMF when compared with the unexposed cells.

CONCLUSIONS:

Alterations in the NQO1 and NQO2 mRNA levels seem at the “5 min field-on/5 min field-off” condition.

Novel non invasive diagnostic strategies in bladder cancer

Bladder cancer is one of the most commonly diagnosed malignancies worldwide, derived from the urothelium of the urinary bladder and defined by long asymptomatic and atypical clinical picture. Its complex etiopathogenesis is dependent on numerous risk factors that can be divided into three distinct categories: genetic and molecular abnormalities, chemical or environmental exposure and previous genitourinary disorders and family history of different malignancies. Various genetic polymorphisms and microRNA might represent useful diagnostic or prognostic biomarkers. Genetic and molecular abnormalities - risk factors are represented by miRNA or genetic polymorphisms proved to be part of bladder carcinogenesis such as: genetic mutations of oncogenes TP53, Ras, Rb1 or p21 oncoproteins, cyclin D or genetic polymorhisms of XPD,ERCC1, CYP1B1, NQO1C609T, MDM2SNP309, CHEK2, ERCC6, NRF2, NQO1Pro187Ser polymorphism and microRNA (miR-143, −145, −222, −210, −10b, 576-3p). The aim of our article is to highlight the most recent acquisitions via molecular biomarkers (miRNAs and genetic polymorphisms) involved in bladder cancer in order to provide early diagnosis, precise therapy according to the molecular profile of bladder tumors, as well as to improve clinical outcome, survival rates and life quality of oncological patients. These molecular biomarkers play a key role in bladder carcinogenesis, clinical evolution, prognosis and therapeutic response and explain the molecular mechanisms involved in bladder carcinogenesis; they can also be selected as therapeutic targets in developing novel therapeutic strategies in bladder malignancies. Moreover, the purpose in defining these molecular non invasive biomarkers is also to develop non invasive screening programs in bladder malignancies with the result of decreasing bladder cancer incidence in risk population.

Association between interleukin-22 genetic polymorphisms and bladder cancer risk

OBJECTIVE

The cytokine interleukin-22 (IL-22), which is produced by T cells and natural killer cells, is associated with tumorigenesis and tumor progression in cancers. However, the role of IL-22 in bladder cancer has not been investigated.

MATERIALS AND METHODS

A prospective hospital-based case-control study comprising 210 patients with pathologically proven bladder cancer and 210 age- and gender-matched healthy controls was conducted. The genotypes of 3 common polymorphisms (-429 C/T, +1046 T/A and +1995 A/C) of the IL-22 gene were determined with fluorogenic 5' exonuclease assays.

RESULTS

Patients with bladder cancer had a significantly higher frequency of the IL-22 -429 TT genotype [odds ratio (OR)=2.04, 95% confidence interval (CI)=1.19, 3.49; p=0.009] and -429 T allele (OR=1.42, 95% CI=1.08, 1.87; p=0.01) than the healthy controls. These findings were still significant after a Bonferroni correction. When stratifying according to the stage of bladder cancer, we found that patients with superficial bladder cancer had a significantly lower frequency of the IL-22 -429 TT genotype (OR=0.48, 95% CI=0.23, 0.98; p=0.04). When stratifying according to the grade and histological type of bladder cancer, we found no statistical association. The IL-22 +1046 T/A and IL-22 +1995 A/C gene polymorphisms were not associated with the risk of bladder cancer.

CONCLUSION

To the authors' knowledge, this is the first report documenting that the IL-22 -429 C/T gene polymorphism is associated with bladder cancer risk. Additional studies are required to confirm this finding.