2'-5' oligoadenylate synthetase 1 polymorphism is associated with prostate cancer

BACKGROUND:

The antiviral, proapoptotic, antiproliferative gene 2′‐5′ oligoadenylate synthetase (2‐5OAS1) converts adenosine triphosphate into a series of 2′‐5′ oligoadenylates (2‐5A). In turn, 2‐5A activates latent ribonuclease (RNaseL), a candidate hereditary prostate cancer gene. OAS1 polymorphism (reference single nucleotide polymorphism [SNP] 2660 [rs2660]) has been associated with increased susceptibility to infections and various diseases. In general, the low‐enzyme‐activity adenine‐adenine (AA) genotype promotes susceptibility, whereas the high‐enzyme‐activity guanosine‐guanosine (GG) genotype confers protection. In this study, the authors investigated the association of this functional OAS1 polymorphism (rs2660) with prostate cancer.

METHODS:

Sample size and power were calculated using a power calculation software program for case‐control genetic association analyses. Genomic DNA samples from a control group (n = 140) and from a case group of patients with prostate cancer (n = 164) were used for genotyping SNPs rs2660, rs1131454, and rs34137742 in all samples. Statistical analyses were performed using a logistic regression model.

RESULTS:

A significant association was observed between the rs2660 genotype (A/G) and prostate cancer. Genotype AA increased the risk, whereas genotype GG decreased the risk of prostate cancer. The GG genotype was not observed in the African American samples. The AA genotype also increased the risk of prostate cancer with age.

CONCLUSIONS:

The OAS1 SNP rs2660 AA genotype was associated significantly with prostate cancer, whereas the GG genotype protected against prostate cancer. OAS1 rs2660 may be a prostate cancer susceptibility polymorphism, which is a significant observation, especially in a context of the OAS1‐RNaseL pathway. Thus, a functional defect in OAS1 because of the rs2660 SNP not only can attenuate RNaseL function but also can alter cell growth and apoptosis independent of RNaseL. Cancer 2011;. © 2011 American Cancer Society.     

Clinical significance of SOD2 and GSTP1 gene polymorphisms in Chinese patients with gastric cancer

BACKGROUND:

Excessive reactive oxygen species (ROS) accumulation is a common phenomenon in carcinogenesis. However, the rationale behind ROS involvement in gastric cancer is unclear. In this study, the authors investigated the clinical significance of the single nucleotide polymorphisms (SNPs) of 2 ROS metabolic process‐related genes: superoxide dismutase 2 (SOD2) and glutathione S‐transferase π (GSTP1).

METHODS:

In total of 929 patients with gastric cancer who had definitive clinicopathologic and follow‐up data were collected. SOD2 reference SNP 4880 (rs4880) and GSTP1 rs1695 genotyping were examined in DNA samples extracted from paraffin‐embedded tumor tissue. Association of the 2 SNPs with each clinicopathologic feature was analyzed using the Pearson chi‐square test and the independent Student t test. Gastric cancer‐specific overall survival was analyzed using Kaplan‐Meier curves and log‐rank tests. Multivariate Cox regression analyses of these SNPs also were performed.

RESULTS:

The SOD2 rs4880 CT + CC genotypes were significantly associated with a high level of lymph node metastasis (P = .023), whereas the GSTP1 rs1695 GA + GG genotypes were significantly associated with larger tumor size (>5 cm long; P = .048). Kaplan‐Meier and Cox regression data indicated that the SOD2 rs4880 CT + CC genotypes alone (hazard ratio, 1.299; 95% confidence interval, 1.053‐1.603; P = .015) and the GSTP1 rs1695 GA + GG combined genotypes (hazard ratio, 1.496; 95% CI, 1.078‐2.074; P = .016) were independent predictors for overall survival.

CONCLUSIONS:

The current data, based on a large cohort (n = 929) of Chinese patients with gastric cancer, suggested that the presence of SOD2 rs4880 and GSTP1 rs1695 genotypes may contribute to cancer progression as well as tumor aggressiveness. The components of ROS metabolism pathways may be potential therapeutic targets for this aggressive malignancy. Cancer 2012. © 2012 American Cancer Society.     

Xeroderma pigmentosum complementation group C single-nucleotide polymorphisms in the nucleotide excision repair pathway correlate with prolonged progression-free survival in advanced ovarian cancer

BACKGROUND:

The nucleotide excision repair (NER) pathway is the principal DNA repair pathway for removing bulky platinum DNA adducts. Suboptimal DNA repair may lead to improved response to platinum agents. The objective of this study was to determine whether single‐nucleotide polymorphisms (SNPs) in NER pathway genes could be markers of platinum response in ovarian cancer.

METHODS:

The authors identified patients with advanced‐stage, papillary serous ovarian cancer who underwent primary cytoreductive surgery followed by platinum‐based chemotherapy. DNA was isolated from peripheral blood specimens. Twenty‐two SNPs within NER genes (xeroderma pigmentosum [XP] complementation group A [XPA], XPB/excision repair cross‐complementing rodent repair deficiency, complementation group 3 [ERCC3], XPC, XPD/ERCC2, XPF/ERCC4, XPG/ERCC5, Cockayne syndrome group B protein [CSB]/ERCC8, ERCC1) were genotyped using polymerase chain reaction analysis.

RESULTS:

In total, 139 patients with stage III and IV papillary serous ovarian cancer were genotyped. The XPC (reference SNP 3731108 [rs3731108]) adenosine‐guanine (AG)/AA genotype versus the GG genotype was associated with prolonged a progression‐free survival (PFS) of 21.3 months versus 13.4 months (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.42‐0.95; P = .03). The XPC (rs1124303) guanosine‐thymidine (GT)/GG genotype versus the TT genotype was associated with a prolonged PFS of 22.8 months versus 14.9 months (HR, 0.47; 95% CI, 0.24‐0.94; P = .03). The XPC poly(AT) (PAT) (?/+)/(?/?) genotype versus the (+/+) genotype was associated with a prolonged PFS of 17 months versus 11.6 months (HR, 0.56; 95% CI, 0.36‐0.89; P = .01). The XPF/ERCC4 (rs12926685) cytidine‐thymidine (CT)/CC genotype versus the TT genotype was associated with a prolonged PFS of 16.7 months versus 12.4 months (HR, 0.63; 95% CI, 0.41‐0.95; P = .03). On multivariate analysis adjusting for breast cancer (BRCA) gene and cytoreductive surgery status, the XPC SNPs remained significantly associated with prolonged PFS.

CONCLUSIONS:

The current results indicated that XPC is a key component of the NER pathway that participates in DNA damage repair. SNPs in the XPC gene may represent novel markers of ovarian cancer response to platinum‐based chemotherapy. Cancer 2012;. © 2011 American Cancer Society.     

Association between DNA repair gene polymorphisms and risk of glioma: A systematic review and meta-analysis

Background

Association studies of germline DNA repair single nucleotide polymorphisms (SNPs) and glioma risk have yielded inconclusive results. We therefore performed a systematic review and meta-analysis of studies investigating this association.

Methods

We identified 27 eligible studies investigating 105 SNPs in 42 DNA repair genes. Of these, 10 SNPs in 7 genes were analyzed in at least 4 studies and were therefore included in our meta-analysis. The meta-analysis was performed for homozygote comparison, heterozygote comparison, and dominant and recessive models by applying a fixed- or random-effects model. The funnel and forest plots were created using RevMan software.

Results

We found that SNPs rs3212986 (odds ratio [OR] = 1.35 (1.08–1.68), P = .008), rs13181 (OR = 1.18 (1.06–1.31), P = .002), and rs25487 (OR = 1.12 (1.03–1.22), P = .007) in DNA repair genes ERCC1, ERCC2 (XPD), and XRCC1 may increase the risk of glioma, while polymorphisms rs1136410 (OR = 0.78 (0.68–0.89), P = .0004) and rs12917 (OR = 0.84 (0.73–0.96), P = .01) in PARP1(ADPRT) and MGMT are associated with decreased susceptibility to glioma. No evidence of significant associations between ERCC2 rs1799793, OGG1 rs1052133, XRCC1 rs25489, XRCC1 rs1799782, or XRCC3 rs861539 and risk of glioma was observed.

Conclusion

This study provides evidence that DNA repair genes ERCC1, ERCC2, and XRCC1 might be low-penetrance glioma-risk genes, while MGMT and PARP1 polymorphisms may confer protection against glioma.     

Glucose metabolism gene polymorphisms and clinical outcome in pancreatic cancer

BACKGROUND:

Altered glucose metabolism is the most common metabolic hallmark of malignancies. The authors tested the hypothesis that glucose metabolism gene variations affect clinical outcome in pancreatic cancer.

METHODS:

The authors retrospectively genotyped 26 single nucleotide polymorphisms from 5 glucose metabolism genes in 154 patients with localized disease and validated the findings in 552 patients with different stages of pancreatic adenocarcinoma. Association between genotypes and overall survival (OS) was evaluated using multivariate Cox proportional hazard regression models with adjustment for clinical predictors.

RESULTS:

Glucokinase (GCK) IVS1 + 9652C > T and hexokinase 2 (HK2) N692N homozygous variants were significantly associated with reduced OS in the training set of 154 patients (P < .001). These associations were confirmed in the validation set of 552 patients and in the combined dataset of all 706 patients (P ≤ .001). In addition, HK2 R844K variant K allele was associated with a better survival in the validation set and the combined dataset (P ≤ .001). When data were further analyzed by disease stage, glutamine‐fructose‐6‐phosphate transaminase (GFPT1) IVS14‐3094T>C, HK2 N692N and R844K in patients with localized disease and GCK IVS1 + 9652C>T in patients with advanced disease were significant independent predictors for OS (P ≤ .001). Haplotype CGG of GPI and GCTATGG of HK2 were associated with better OS, respectively, with P values of .004 and .007.

CONCLUSIONS:

The authors demonstrated that glucose metabolism gene polymorphisms affect clinical outcome in pancreatic cancer. These observations support a role of abnormal glucose metabolism in pancreatic carcinogenesis. Cancer 2011. © 2010 American Cancer Society.     

DNA mismatch repair network gene polymorphism as a susceptibility factor for pancreatic cancer

DNA repair plays a critical role in human cancers. We hypothesized that DNA mismatch repair gene variants are associated with risk of pancreatic cancer. We retrospectively genotyped 102 single‐nucleotide polymorphisms (SNPs) of 13 mismatch repair related genes in 706 patients with pancreatic cancer and 706 cancer‐free controls using the mass spectroscopy‐based MassArray method. Association of genotype with pancreatic cancer risk was tested by multivariate logistic regression models. A significance level of P ≤ 0.0015 was set at the false discovery rate (FDR) <1% using the Beta‐Uniform Mixture method. We found 28 SNPs related to altered pancreatic cancer risk (P < 0.05). Adjusting for multiple comparisons, MGMT I143V AG/GG, PMS2 IVS1‐1121C > T TC/TT, and PMS2L3 Ex1 + 118C > T CT/TT genotypes showed significant main effects on pancreatic cancer risk at FDR <1% with OR (95% CI) of 0.60 (0.46–0.80), 1.44 (1.14–1.81), and 5.54 (2.10–14.61), respectively (P ≤ 0.0015). To demonstrate genotype–phenotype association, we measured O ⁶‐ethylguanosine (O ⁶‐EtGua) adduct levels in vitro by immunoslot blot assay in lymphocytes treated with N‐ethyl‐N‐nitrosourea (ENU) in 297 case/control subjects. MGMT I143V GG, MGMT K178R GG, MSH6 G39E AG/AA, PMS2L3 IVS3 + 9A > G GA and TP73 IVS1‐7449G > C CG/CC genotypes correlated with a higher level of ENU‐induced DNA adducts. Haplotypes of MGMT, MSH6, PMS2, PMS2L3, and TP73 were significantly associated with pancreatic cancer risk (P ≤ 0.0015). Our findings suggest that mismatch repair gene variants may affect susceptibility to pancreatic cancer. © 2011 Wiley Periodicals, Inc.     

Caspase‐8 polymorphisms and risk of gallbladder cancer in a Northern Indian population

Caspase‐8 (CASP8) is a key controller of apoptosis, and its deregulation plays an important role in carcinogenesis. To evaluate the role of CASP8 polymorphisms in gallbladder cancer (GBC), we examined the risk associated with three single‐nucleotide polymorphisms (SNPs) in a case–control study in North Indian population. Genotypes and haplotypes of the CASP8 polymorphisms (?652 6N ins/del; rs3834129, Ex13 + 51G > C; rs1045485 and IVS12‐19 G > A; rs3769818) were determined for 230 GBC patients and 230 cancer‐free controls randomly selected from the population. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated in multivariate logistic regression analysis for the association of individual SNPs and haplotypes with GBC. Carriers for the “del” allele of rs3834129 SNP were associated with a 0.60‐fold decreased risk for GBC (95% CI = 0.42–0.88; P_trend = 0.005). In the combined analysis of the three CASP8 variants, we found that the individuals with the diplotypes carrying two copies of the common CASP8 del‐G‐G haplotype had 0.35‐fold reduced risk (95% CI = 0.14–0.85) when compared with the diplotype containing 0–1 copy. The false‐positive report probability (FPRP) approach advocated that these results were noteworthy (FPRP < 0.5). The molecular modeling results of rs1045485 polymorphism indicated that the overall configuration of both wild‐type and polymorphic CASP8 protein were similar, with negligible deviation at the site of the polymorphism itself. In summary, low penetrance variants in CASP8 gene may alter the susceptibility toward GBC. © 2010 Wiley‐Liss, Inc.     

Potentially functional polymorphisms in DNA repair genes and non-small-cell lung cancer survival: a pathway-based analysis

To assess systematically whether potentially functional polymorphisms in DNA repair genes influence the clinical behavior of non‐small‐cell lung cancer (NSCLC), we examined the impact of a comprehensive panel of 218 signal nucleotide polymorphisms (SNP) in 50 candidate DNA repair genes on overall survival of NSCLC in a case‐cohort of 568 lung cancer patients. SNPs associated with lung cancer prognosis primarily mapped to 14 genes in different repair pathways, and 6 SNPs were remained in the final model after multivariate stepwise Cox regression analysis: ATM rs189037; MRE11A rs11020802; ERCC2 rs1799793; MBD4 rs140693; XRCC1 rs25487, and PMS1 rs5742933. In the combined analysis of these 6 SNPs, an increasing number of unfavorable loci was associated with a poorer prognosis (P for trend: <0.0001) and patients having 2–4 unfavorable loci had a 1.99‐fold elevated risk of death 95% confidence interval (CI) = 1.58–2.50, compared with those carrying 0–1 unfavorable loci, and this elevated risk was more evident among stages I–II patients (hazard ratio = 3.04, 95% CI = 1.86–4.98, P for heterogeneity: 0.07). Furthermore, a significant effect of SNPs in nucleotide excision repair pathway on lung cancer survival was observed among 185 stages III–IV patients treated with platinum‐based chemotherapy without surgical operation: XPC rs2228000 (Ala499Val; P = 0.002) and ERCC1 rs11615 (Asn118Asn; P = 0.012). Our data indicate that potentially functional polymorphisms in DNA repair genes may serve as candidate prognostic markers of clinical outcome of NSCLC. © 2011 Wiley Periodicals, Inc.     

Association of Single Nucleotide Polymorphisms of the MDM4 Gene With the Susceptibility to Breast Cancer in a Southeast Iranian Population Sample

Introduction

The murine double minute 4 (MDM4) protein is a negative regulator of p53, and its upregulation has been observed in many tumor types. Previous literature suggested that genetic variations in the MDM4 gene are associated with risk of different cancers. The objective of the present study was to examine the effect of 3 common genetic variants of MDM4, rs4245739 A>C, rs11801299 G>A, and rs1380576 C>G, on the risk of breast cancer (BC) in a southeast Iranian population sample.

Association of the progesterone receptor gene with endometrial cancer risk in a Chinese population

BACKGROUND:

Single nucleotide polymorphisms (SNPs) in the progesterone receptor (PGR) gene have been associated with the risk of endometrial cancer. However, to the authors' knowledge, no study to date has systematically evaluated the role of the PGR gene in endometrial carcinogenesis.

METHODS:

Exposure information and DNA samples collected in the Shanghai Endometrial Cancer Study, a population‐based case‐control study of 1204 incident cases and 1212 age‐ and frequency‐matched population controls, were used in this study. Seven tag SNPs were identified for the PGR gene plus the 5‐kilobase (kb) flanking regions using the Han Chinese data from the HapMap project with a pairwise correlation coefficient (r²) ≥ 0.90. These 7 SNPs captured 92% of SNPs in the region with a pairwise r² ≥ 0.90 or 100% of SNPs with a pairwise r² ≥ 0.80. Genotyping of polymorphisms was performed by using the Affymetrix MegAllele Targeted Genotyping System. A logistic regression model was used to compute adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS:

Of 7 tag SNPs that were assessed, 2 polymorphisms in the 3′ flanking region of the PGR gene, reference SNP identification number (rs) 11224561 (rs11224561) and rs471767, were associated with the risk of endometrial cancer. The cytosine/cytosine (CC) genotype of SNP rs11224561 was associated with decreased risk (OR, 0.68; 95% CI, 0.50‐0.92) compared with the thymine/thymine (TT) genotype. Carrying the guanine (G) allele of the rs471767 SNP also was associated with decreased risk, although the association was not statistically significant (OR, 0.78, 95%CI, 0.59‐1.04 and OR, 0.32, 95%CI, 0.03‐3.05 for the adenine [A]G and GG genotypes, respectively, compared with the homozygote AA).

CONCLUSIONS:

The current findings suggested that polymorphisms in the 3′ flanking region of the PGR gene may be associated with the risk of endometrial cancer. Cancer 2009. © 2009 American Cancer Society.     

SNP-SNP interactions between DNA repair genes were associated with breast cancer risk in a Korean population

BACKGROUND:

Single nucleotide polymorphisms (SNPs) in nucleotide excision repair (NER) pathway genes may modulate DNA repair capacity and increase susceptibility to breast cancer (BC). A case‐control study was conducted by evaluating genes involved in DNA repair to identify polymorphisms associated with BC.

METHODS:

The 384 SNPs of 38 candidate genes were genotyped using the Illumina GoldenGate method. Genotypes were determined in a case‐control study that consisted of 346 BC patients and 361 controls. Odds ratios and 95% confidence intervals were computed using logistic regression models. Multiple logistic regression models adjusted for age, family history of BC, and body mass index were used.

RESULTS:

Gene–gene interaction analysis among the DNA repair pathway genes showed significant effects on BC risk. ERCC2 rs50872 (TC genotype) in combination with XPA rs2808668 (TC genotype) and rs1800975 (AG genotype) was strongly associated with an increased risk of BC (P = .0004 and .0002, P_Bonferroni = .023 and .014, respectively). Moreover, the T‐G (including rs2808668 and rs1800975) haplotype in XPA combined with the ERCC2 T allele in rs50872 carriers was also associated with additive risk effect of BC (odds ratios: 2.58, 2.62, and 3.49, respectively).

CONCLUSION:

Genetic variation in DNA repair genes involved in NER mechanisms increased the risk of BC development. These results suggested that a stronger combined effect of SNPs via gene–gene interaction may help to predict BC risk. Cancer 2012;. © 2011 American Cancer Society.     

A single nucleotide polymorphism in the alcohol dehydrogenase 7 gene (alanine to glycine substitution at amino acid 92) is associated with the risk of squamous cell carcinoma of the head and neck

BACKGROUND:

The authors conducted a hospital‐based study of 1110 patients with squamous cell carcinoma of the head and neck (SCCHN) and a control group of 1129 patients to replicate the associations reported by a recent, large European study between 2 potentially functional single nucleotide polymorphisms (SNPs) of the alcohol dehydrogenase (ADH) genes, a substitution in ADH1B at amino acid 48 from arginine to histidine (R48H) (reference SNP number [rs]1229984; guanine to adenine [G→A]) and a substitution in ADH7 at amino acid 92 from alanine to glycine (A92G) (rs1573496; cytosine to guanine [C→G]), and the risk of squamous cell carcinoma of the head and neck (SCCHN).

METHODS:

Multivariate logistic regression was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). False‐positive report probabilities (FPRPs) also were calculated for significant findings.

RESULTS:

The ADH7 A92G GG and combined CG + GG genotypes were associated with a decreased risk of SCCHN (GG: adjusted OR, 0.32; 95% CI, 0.13‐0.82; CG + GG: adjusted OR, 0.74; 95% CI, 0.59‐0.94; FPRP, .098) compared with the CC genotype. This association was also evident in subgroups of older patients (aged >57 years), men, former smokers, patients with oral cancer, and patients with N) lymph node status (P < .05 for all); however, such associations were not observed for the ADH1B R48H SNP.

CONCLUSIONS:

The current results support the ADH7 A92G SNP as a marker for the risk of SCCHN in non‐Hispanic white populations. Cancer 2010. © 2010 American Cancer Society.     

IL12 polymorphisms,HBV infection and risk of hepatocellular carcinoma in a high‐risk Chinese population

To investigate the association between the potentially functional polymorphisms in IL12A and IL12B, HBV infection and risk of hepatocellular carcinoma in a Chinese population, we genotyped three polymorphisms, rs568408 (3′UTR G>A), rs2243115 (5′UTR T>G) in IL12A and rs3212227 (3′UTR A>C) in IL12B in a case–control study of 869 hepatocellular carcinoma (HCC) cases and 891 cancer‐free controls. We found that the IL12A rs568408 GA/AA variant genotypes were associated with a significantly increased risk of HCC (adjusted odds ratio (OR) = 1.53, 95% confidence interval (CI) = 1.17–2.00), compared with the wild‐type GG homozygote. In the stratified analyses, the increased risk of HCC associated with rs568408 GA/AA was more evident in patients who were negative for HBsAg (adjusted OR = 1.71, 95% CI = 1.23–2.39). However, no significant associations between IL12A rs2243115 T/G, IL12B rs3212227 A/C and risk of HCC were observed. Our findings indicate that IL12A rs568408 may contribute to the risk of HCC and modify HCC risk associated with HBV infection.     

Prognostic impact of the isocitrate dehydrogenase 1 single‐nucleotide polymorphism rs11554137 in malignant gliomas

BACKGROUND.

The IDH1 gene, which encodes isocitrate dehydrogenase 1, is frequently mutated in gliomas and acute myeloid leukemia. The single‐nucleotide polymorphism (SNP) (reference SNP no. rs11554137:C>T) located on IDH1 codon 105 has been associated with a poor outcome in patients with acute myeloid leukemia but has not been investigated in patients with gliomas.

METHODS.

The IDH1 codon 105 SNP was genotyped first in a series of 952 patients with grade 2 through 4 gliomas and was correlated with outcomes and tumor genomic profile. Then, it was genotyped in 2 validations sets of 306 patients with glioblastoma (GBM) and 591 patients with glioma.

RESULTS.

The minor allele codon 105 glycine (GGT) SNP (IDH1^105GGT) was identified in 98 of 952 patients (10.3%) and was not associated with the codon 132 (IDH1¹³²) mutation. Patients who had GMB with the IDH1^105GGT variant had a poorer outcome than patients without the variant (median overall survival [OS], 10.7 months vs 15.5 months; P = .001; median progression‐free survival [PFS], 6.4 months vs 8.5 months; P = .003). The prognostic impact was confirmed in an independent validation set of 306 GBMs from the same center (median PFS, 6.8 months vs 9.7 months; P = .006; median OS, 13.9 months vs 18.8 months; P = .0187). In the second validation cohort (591 grade 2‐4 gliomas), a significant association was observed between IDH1^105GGT and an adverse prognosis for the overall series and for patients with World Health Organization grade 3 gliomas, but the difference did not reach significance in patients with GBM.

CONCLUSIONS.

Taken together, the current data strongly suggested an association between the SNP rs11554137:C>T polymorphism and adverse outcomes in patients with malignant glioma. A single‐nucleotide polymorphism (SNP) located on codon 105 of the isocitrate dehydrogenase 1 (IDH1) gene (reference SNP rs11554137) is analyzed in 3 independent series of patients with gliomas. The SNP rs11554137 is independent of the occurrence of somatic mutation on IDH1 codon 132, but, per se, has a prognostic impact in malignant gliomas. Cancer 2013. © 2012 American Cancer Society.     

Phase II Study of Satraplatin and Prednisone in Patients With Metastatic Castration-Resistant Prostate Cancer: A Pharmacogenetic Assessment of Outcome and Toxicity

BackgroundWe assessed the effect of excision repair cross-complementing group 1 (ERCC1) and x-ray cross-complementing group 1 (XRCC1) gene polymorphisms on treatment outcomes with satraplatin and prednisone in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel-based therapy.Patients and MethodsTwenty-four patients were enrolled in this single arm study. The primary objective was to determine if the presence of ERCC1 Asn118Asn (N118N, 500C>T, rs11615) and XRCC1 Arg399Gln (R399Q, 1301G>A, rs25487) genetic variants might be associated with an impact on progression-free survival (PFS); secondary objectives included overall response, survival, and toxicity.ResultsAfter population stratification by race, white patients carrying heterozygous or variant genotypes at the ERCC1 C>T locus had a >3-fold longer median PFS (5.8 vs. 1.8 months; 2P = .18, adjusted) and 5-fold longer median overall survival (OS) (15.7 vs. 3.2 months; 2P = .010, adjusted) than did patients carrying only wild-type alleles. For the XRCC1 G>A variant, without regard to race, patients carrying the wild-type GG alleles had a longer PFS (9.3 months) than those carrying GA or AA alleles (2.7 months; 2P = .02). Similarly, those carrying GG alleles did not reach median OS, whereas those carrying GA or AA alleles had a median OS of 9.6 months (2P = .12, adjusted). Multivariable analysis by using Cox proportional hazards modeling demonstrated that only XRCC1 was associated with PFS.ConclusionsTo our knowledge, this is the first prospective study to date in patients with metastatic castration-resistant prostate cancer that describes predictive germline polymorphisms of ERCC1 and XRCC1 for assessing the clinical activity of satraplatin.     

p14ARF genetic polymorphisms and susceptibility to second primary malignancy in patients with index squamous cell carcinoma of the head and neck

BACKGROUND:

p14^ARF, an alternate reading frame (ARF) product of the cyclin‐dependent kinase inhibitor 2A locus, plays a critical role in crosstalk between the tumor protein 53 (p53) and retinoblastoma (Rb) pathways and in cellular anticancer mechanisms. Therefore, the authors of this report investigated the association between single nucleotide polymorphisms (SNPs) of the p14^ARF gene and the risk of developing a second primary malignancy (SPM) after an index squamous cell carcinoma of the head and neck (SCCHN).

METHODS:

The log‐rank test and Cox proportional hazards models were used to assess the association of 2 p14^ARF SNPs (reference SNP [rs]3731217 and rs3088440) with SPM‐free survival and with the risk of developing an SPM among 1287 patients who had SCCHN.

RESULTS:

Patients with either p14^ARF variant genotypes of the 2 polymorphisms had a significantly reduced SPM‐free survival compared with patients with no variant genotypes (log‐rank test; P = .006). Compared with the p14^ARF thymine‐thymine (TT) and guanine‐guanine (GG) genotypes, the variant genotypes of p14^ARF TG/GG and guanine‐adenine (GA)/AA were associated with a significantly moderately increased risk of developing an SPM (p14^ARF rs3731217: adjusted hazard ratio [aHR], 1.48; 95% confidence interval [CI], 1.00‐2.19; p14^ARF rs3088440: aHR, 1.61; 95% CI, 1.07‐2.43). Moreover, after combining the variant genotypes of the 2 SNPs, patients who had variant genotypes were at significantly greater risk of developing an SPM compared with patients who had no variant genotypes (aHR, 3.07; 95% CI, 1.54‐6.12), and the risk was particularly pronounced in several subgroups.

CONCLUSIONS:

The current results suggested that there is a modestly increased risk of developing an SPM after an index SCCHN with each p14^ARF polymorphism, and there is an even greater risk of developing an SPM for patients with combined variant genotypes of the 2 SNPs. Therefore, p14^ARF polymorphisms may be susceptible markers of the risk of developing an SPM in patients with SCCHN. Cancer 2011. © 2010 American Cancer Society.     

Contribution of dihydropyrimidinase gene alterations to the development of serious toxicity in fluoropyrimidine-treated cancer patients

Purpose

Decreased 5-fluorouracil catabolism has been considered a major factor contributing to fluoropyrimidine (FP)-related toxicity. Alterations in the dihydropyrimidine dehydrogenase gene coding for the first and rate-limiting enzyme of FP catabolic pathway could explain toxicity in only a limited proportion of FP-treated patients. The importance of gene variants in dihydropyrimidinase (DPYS) coding for subsequent catabolic enzyme of FP degradation is not fully understood.

Methods

We performed genotyping of DPYS based on denaturing high-performance liquid chromatography in 113 cancer patients including 67 with severe FP-related toxicity and 46 without toxicity excellently tolerating FPs treatment.

Results

We detected nine DPYS variants including four located in non-coding sequence (c.-1T>C, IVS1+34C>G, IVS1-58T>C, and novel IVS4+11G>T), four silent (c.15G>A, c.216C>T, and novel c.105C>T and c.324C>A), and one novel missense variant c.1441C>T (p.R481W). All novel alterations were detected once only in patients without toxicity. The c.-1T>C and IVS1-58T>C variants were found to modify the risk of toxicity. The CC carriers of the c.-1C alleles were at higher risk of mucositis (OR = 4.13; 95% CI = 1.51–11.31; P = 0.006) and gastrointestinal toxicity (OR = 3.54; 95% CI = 1.59–7.88; P = 0.002), whereas the presence of the IVS1-58C allele decreased the risk of gastrointestinal toxicity (OR = 0.4; 95% CI = 0.17–0.93; P = 0.03) and leucopenia (OR = 0.29; 95% CI = 0.08–1.01; P = 0.05).

Conclusions

Our results indicate that missense and nonsense variants in DPYS are infrequent, however, the development of serious primarily gastrointestinal toxicity could be influenced by non-coding DPYS sequence variants c.-1T>C and IVS1-58T>C.     

Possible association between polymorphisms of human vascular endothelial growth factor A gene and susceptibility to glioma in a Chinese population

Vascular endothelial growth factor A (VEGFA), one of the most predominant mediators of pathologic angiogenesis, plays a critical role in glioma carcinogenesis and development via promoting tumor growth. We hypothesized that VEGFA polymorphisms may influence glioma risk. We recently genotyped 9 VEGFA single‐nucleotide polymorphisms (SNPs) in 766 glioma patients and 824 cancer‐free controls selected from a Chinese population. We evaluated the glioma risk conferred by individual SNPs, haplotypes as well as cumulative SNP effect. In the single‐locus analysis, we found that rs2010963 (G+405C, G‐634C) [odds ratio (OR) = 1.29; 95% confidence interval (CI) = 1.04–1.58; GC/CC vs. GG] and rs3025030 (OR = 2.21; 95% CI = 1.18–4.14; CC vs. GG/GC) were associated with increased risk for glioma, and rs3024994 (OR = 0.66; 95% CI = 0.47–0.94; CT/TT vs. CC) was associated with reduced glioma risk, albeit insignificant after Bonferroni correction for multiple comparisons. The haplotype‐based analysis revealed that AGG in block 1 and ATT, ACT in block 2 were associated with 20–40% reductions in glioma risk. The inverse association of haplotype AGG containing rs2010963G remained significant after correction for multiple testing (p = 0.002, p_corrected = 0.022). The aforementioned 3 SNPs revealed a significant cumulative risk effect; the increased risk for glioma was 1.38‐fold for each additional adverse genotype he or she carries (p_trend = 8.4 × 10^?5). Our findings suggested that VEGFA variants may be involved in glioma risk. Larger studies with ethnically diverse populations are warranted to confirm the results reported in this investigation.