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.     

Genetic variants of the nonhomologous end joining gene LIG4 and severe radiation pneumonitis in nonsmall cell lung cancer patients treated with definitive radiotherapy

BACKGROUND:

Nonhomologous end joining (NHEJ) is a pathway that repairs DNA double‐strand breaks (DSBs) to maintain genomic stability in response to irradiation. The authors hypothesized that single nucleotide polymorphisms (SNPs) in NHEJ repair genes may affect clinical outcomes in patients with nonsmall cell lung cancer (NSCLC) who receive definitive radio(chemo)therapy.

METHODS:

The authors genotyped 5 potentially functional SNPs—x‐ray repair complementing defective repair in Chinese hamster cells 4 (XRCC4) reference SNP (rs) number rs6869366 (?1394 guanine to thymine [?1394G→T] change) and rs28360071 (intron 3, deletion/insertion), XRCC5 rs3835 (guanine to adenine [G→A] change at nucleotide 2408), XRCC6 rs2267437 (?1310 cytosine to guanine [C→G) change], and DNA ligase IV (LIG4) rs1805388 (threonine‐to‐isoleucine change at codon 9 [T9I])—and estimated their associations with severe radiation pneumonitis (RP) (grade ≥3) in 195 patients with NSCLC.

RESULTS:

A predictive role in radiation pneumonitis (RP) development was observed for the LIG4 SNP rs1805388 (adjusted hazard ratio, 2.08; 95% confidence interval, 1.04‐4.12; P = .037 for the CT/TT genotype vs the CC genotype). In addition, men with the TT genotype of the XRCC4 rs6869366 SNP and women with AG + AA genotypes of the XRCC5 rs3835 SNP also were at increased risk of developing severe RP.

CONCLUSIONS:

The current results indicated that NHEJ genetic polymorphisms, particularly LIG4 rs1805388, may modulate the risk of RP in patients with NSCLC who receive definitive radio(chemo)therapy. Large studies will be needed to confirm these findings. Cancer 2011;. © 2011 American Cancer Society.     

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.     

Polymorphisms in ERCC2, MSH2, and OGG1 DNA repair genes and gallbladder cancer risk in a population of Northern India

BACKGROUND:

Genetic variants of DNA repair enzymes may lead to genetic instability and contribute to gallbladder (GB) carcinogenesis.

METHODS:

A case‐control study (230 GB carcinogenesis patients and 230 controls) was undertaken to evaluate whether genetic variations in 3 DNA repair genes ERCC2 (Asp312Asn [rs1799793] and Lys751Gln [rs13181]), MSH2 (?118T>C [rs2303425] and IVS1 + 9G>C [rs2303426]), and OGG1 (Ser326Cys [rs1052133] and 748‐15C>G [rs2072668]) are associated with GB carcinogenesis risk in a North Indian population.

RESULTS:

The authors found that the ERCC2 Asp312Asn AA, MSH2 IVS1 + 9G>C CC, OGG1 Ser326Cys GG and CG + GG, and OGG1 748‐15C>G GG and CG + GG genotypes were significantly associated with an increased risk of GB carcinogenesis (odds ratio [OR], 2.1, 1.8, 2.5, 1.8, 2.0, and 1.6, respectively). In contrast, ERCC2 Lys751Gln, and MSH2 ?118T>C markers showed no significant associations with GB carcinogenesis risk, although because of the small sample size their effects cannot be ruled out. Female GB carcinogenesis patients with the OGG1 748‐15C>G GG, OGG1 Ser326Cys GG, and ERCC2 Asp312Asn genotypes had a greater risk for developing the disease (OR, 3.6, 7.7, and 2.7, respectively). There was a significant interaction between MSH2 IVS1 + 9G>C and OGG1 748‐15C>G polymorphisms (P = .001). Furthermore, individuals with >6 variant alleles of the studied polymorphisms were at 4‐fold increased risk for developing GB carcinogenesis. Classification and Regression Tree analysis revealed potential higher‐order gene‐gene interactions and categorized a few higher‐risk subgroups for GB carcinogenesis.

CONCLUSIONS:

These results suggest that genetic variants in the DNA repair pathways may be involved in GB carcinogenesis etiology. Cancer 2010. © 2010 American Cancer Society.     

Polymorphisms in the cytotoxic T-lymphocyte antigen 4 gene and cancer risk: a meta-analysis

BACKGROUND:

Polymorphisms in the cytotoxic T‐lymphocyte antigen 4 (CTLA‐4) gene have been implicated in susceptibility to cancer, but the many published studies have reported inconclusive results. The objective of the current study was to conduct a meta‐analysis investigating the association between polymorphisms in the CTLA‐4 gene and the risk of cancer.

METHODS:

The PubMed and EMBASE databases were searched for all articles published up to September 19, 2010 that addressed cancer and polymorphisms, variants, or mutations of CTLA‐4. A statistical analysis was performed using proprietary statistical software.

RESULTS:

Three polymorphisms (+49 adenine/guanine [+49A/G], ?318 cytosine/thymine [?318C/T], and the +6230G/A polymorphism [CT60]) in 48 case‐control studies from 27 articles were analyzed. The results indicated that individuals who carried the +49 G allele (AG + GG) had a 16% decreased risk of cancer compared with homozygotes (+49AA; odds ratio [OR], 0.84; 95% confidence interval [CI], 0.74‐0.95). However, there was no significant association between the risk of cancer and the ?318C/T polymorphism or the CT60 polymorphism (?318C/T: OR, 1.23; 95% CI, 0.99‐1.54 for TT + TC vs CC; CT60: OR, 1.02; 95% CI, 0.80‐1.29 for AA + AG vs GG). In further stratified analyses for the +49A/G and ?318C/T polymorphisms, the decreased risk of cancer remained in subgroups of Europeans, patients with breast cancer, and patients with lung cancer for the +49A/G polymorphism; whereas an increased risk of cancer was observed among Europeans for the ?318C/T polymorphism.

CONCLUSIONS:

Results from the current meta‐analysis suggested that the +49A/G and ?318C/T polymorphisms in CTLA‐4 are risk factors for cancer. To further evaluate gene‐gene and gene‐environment interactions between CTLA‐4 polymorphisms and the risk of cancer, more studies with larger groups of patients will be required. Cancer 2011;. © 2011 American Cancer Society.     

MicroRNA-137 promoter methylation is associated with poorer overall survival in patients with squamous cell carcinoma of the head and neck

BACKGROUND:

The overall 5‐year survival rate of approximately 60% for head and neck cancer patients has remained essentially unchanged over the past 30 years. MicroRNA‐137 (miR‐137) plays an essential role in cell‐cycle control at the G1/S‐phase checkpoint. However, the aberrant miR‐137 promoter methylation observed in squamous cell carcinoma of the head and neck (SCCHN) suggests a tumor‐specific molecular defect that may contribute to disease progression.

METHODS:

The goal of this study was to assess, in formalin‐fixed, paraffin‐embedded tumor tissue, the association between miR‐137 promoter methylation and survival (both overall and disease free) and with prognostic factors including stage, tumor size, lymph node positivity, tumor grade, and surgical tumor margin positivity.

RESULTS:

The promoter methylation status of miR‐137 was ascertained by methylation‐specific polymerase chain reaction and detected in 11 of 67 SCCHN patients (16.4%), with no significant differences according to site (oral cavity, pharynx, larynx). Methylation of the miR‐137 promoter was significantly associated with overall survival (hazard ratio, 3.68; 95% confidence interval, 1.01‐13.38) but not with disease‐free survival or any of the prognostic factors evaluated.

CONCLUSIONS:

The results of this study indicate that miR‐137 is methylated in tumor tissue from pharyngeal and laryngeal squamous cancers, in addition to oral squamous cell carcinoma, and that miR‐137 promoter methylation has potential utility as a prognostic marker for SCCHN. Cancer 2011. © 2010 American Cancer Society.     

Germline polymorphisms in patients with advanced nonsmall cell lung cancer receiving first-line platinum-gemcitabine chemotherapy: a prospective clinical study

BACKGROUND:

The authors assessed the impact of germline polymorphisms on clinical outcome in patients with advanced nonsmall cell lung cancer (NSCLC) who received platinum‐gemcitabine (PG) chemotherapy.

METHODS:

In total, 137 patients with stage IIIB/IV NSCLC were included who received first‐line PG chemotherapy (74% of patients received cisplatin, and 26% received carboplatin). Twenty‐three germline polymorphisms that were identified in peripheral blood samples were analyzed for progression‐free survival (PFS), treatment response, overall survival (OS), and toxicity.

RESULTS:

The median PFS was 5.8 months, the median OS was 10.2 months, and 44 patients (32%) had a partial treatment response. Carriers of the excision repair cross‐complementation group 1 (ERCC1) mutant thymine (T) allele had a lower treatment response rate (29% vs 52%; P = .02), shorter PFS (adjusted hazard ratio [HR], 1.60; P = .04), and shorter OS (adjusted HR, 1.54; P = .05) compared with carriers of the wild‐type cytosine/cytosine (CC) genotype. The xeroderma pigmentosum group A member 10 (XPD10) mutant adenine (A) allele (adjusted HR, 0.64; P = .04) and the x‐ray cross‐complementing group 1 (XRCC1) mutant guanine (G) allele (adjusted HR, 0.51; P = .02) also were independent predictors of OS. Carriers of the mutant adenosine triphosphate‐dependent DNA helicase Q1 (RECQ1) C allele or the mutant cytidine deaminase (CDA) C allele were more likely to experience severe leukocytopenia (26% vs 10% [P = .03] and 28% vs 11% [P = .02], respectively) compared with wild‐type genotype carriers. Patients who carried the homozygous mutant glutathione S‐transferase π 1(GSTP1) GG genotype were at considerable risk for severe platinum‐associated polyneuropathy (18% vs 3% in wild‐type vs heterozygous mutant patients, respectively; P = .01).

CONCLUSIONS:

To the authors' knowledge, this is the first prospective study to date in patients with advanced NSCLC describing predictive germline polymorphisms not only for the clinical activity of PG chemotherapy (ERCC1, XPD10) but also for its toxicity (GSTP1, RECQ1, CDA). Nonplatinum‐containing chemotherapy in carriers of the ERCC1 T allele or the XPD10 G allele should be studied prospectively. Cancer 2012;. © 2011 American Cancer Society.     

Association of VEGF and VEGFR2 single nucleotide polymorphisms with hypertension and clinical outcome in metastatic clear cell renal cell carcinoma patients treated with sunitinib

PURPOSE:

Biomarkers that predict response or toxicity to antiangiogenic therapy are sought to favorably inform the risk/benefit ratio. This study evaluated the association of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) genetic polymorphisms with the development of hypertension (HTN) and clinical outcome in metastatic clear cell renal cell carcinoma (MCCRCC) patients treated with sunitinib.

PATIENT AND METHODS:

Sixty‐three MCCRCC patients receiving sunitinib (50 mg 4/2) with available blood pressure (BP) data and germline DNA were retrospectively identified. A panel of candidate VEGF and VEGFR2 single nucleotide polymorphisms (SNPs) were evaluated for associations with the development of hypertension and clinical outcome.

RESULTS:

VEGF SNP ?634 genotype was associated with the prevalence and duration of sunitinib‐induced hypertension (as defined by systolic pressure ≥150 mmHg and/or diastolic pressure ≥90 mmHg) in both univariable analysis (P = .03 and .01, respectively) and multivariable analysis, which adjusted for baseline BP and use of antihypertension medication (P = .05 and .02, respectively). Patients with the GG genotype were estimated to have a greater likelihood of being hypertensive during treatment compared with patients with the CC genotype (odds ratio of 13.62, 95% confidence interval [CI] 3.71‐50.04). No single VEGF or VEGFR SNPs were found to correlate with clinical outcome. However, the combination of VEGF SNP 936 and VEGFR2 SNP 889 were associated with overall survival after adjustment for prognostic risk group (P = .03).

CONCLUSIONS:

In MCCRCC patients treated with sunitinib, VEGF SNP ?634 is associated with hypertension and a combination of VEGF SNP 936 and VEGFR2 SNP 889 genotypes is associated with overall survival. Cancer 2012;. © 2011 American Cancer Society.     

Genetic variants of the p53 and p73 genes jointly increase risk of second primary malignancies in patients after index squamous cell carcinoma of the head and neck

BACKGROUND:

Because of the structural and biochemical similarities between the antitumor p53 and p73 proteins, the authors hypothesized that individuals who carry high‐risk genotypes of p53 codon 72 and p73 G4C14‐to‐A4T14 polymorphisms have a higher risk of developing second primary malignancy (SPM) after index squamous cell carcinoma of the head and neck (SCCHN).

METHODS:

A cohort of 1269 patients with index cases of SCCHN was recruited between May 1995 and January 2007 at The University of Texas MD Anderson Cancer Center and followed for SPM development. Patients were genotyped for p53 codon 72 and p73 G4C14‐to‐A4T14 polymorphisms. A log‐rank test and Cox proportional hazard models were used to compare SPM‐free survival and SPM risk among different risk groups with the combined risk genotypes of the 2 polymorphisms.

RESULTS:

The data demonstrated that patients with p53 WP + PP and p73 GC/GC genotypes had a worse SPM‐free survival and an increased SPM risk compared with the corresponding p53 WW and p73 GC/AT + AT/AT genotypes. After combining the 2 polymorphisms, a borderline significantly or significantly reduced SPM‐free survival and increased SPM risk were observed in the medium‐risk group (p53 WW and p73 GC/GC or p53 P carriers and p73 AT carriers) and high‐risk group (p53 P carriers and p73 GC/GC) compared with low‐risk group (p53 WW and p73 AT carriers), respectively.

CONCLUSIONS:

The results suggest an increased risk of SPM after index SCCHN with both p53 and p73 polymorphisms individually and in combination. Cancer 2011;. © 2011 American Cancer Society.     

Modifying effect of MDM4 variants on risk of HPV16-associated squamous cell carcinoma of oropharynx

BACKGROUND:

The p53 pathway plays a critical role in maintaining genomic stability and preventing tumor formation. Given the roles of both MDM4 and HPV16 E6 oncoproteins in inhibition of p53 activity, we tested the hypothesis that MDM4 polymorphisms are associated with the risk of HPV16‐associated squamous cell carcinoma of head and neck (SCCHN).

METHODS:

Genotyping was conducted on 3 tagging single nucleotide polymorphisms (rs11801299 G>A, rs10900598 G>T, and rs1380576 C>G) in MDM4, and serology was used to determine HPV 16 exposure in 380 cases and 335 cancer‐free controls that were frequency‐matched by age, sex, smoking, and drinking status.

RESULTS:

None of 3 MDM4 polymorphisms alone was significantly associated with risk of overall SCCHN. With further analysis stratified by HPV16 serology and tumor site, we found that each polymorphism individually modified the risk of HPV16‐associated squamous cell carcinoma of the oropharynx (SCCOP), and such effect modification was particularly pronounced in never smokers and never drinkers.

CONCLUSION:

The risk of HPV16‐associated SCCOP could be modified by MDM4 polymorphisms. Large and prospective studies are needed to validate our findings. Cancer 2011;. © 2011 American Cancer Society.     

Human mu-opioid receptor gene A118G polymorphism predicts the efficacy of tramadol/acetaminophen combination tablets (ultracet) in oxaliplatin-induced painful neuropathy

BACKGROUND:

The A118G polymorphism of the mu‐opioid receptor gene (OPRM1), resulting in the substitution of an amino acid, has been found to be associated with functional effects and response to opioid treatment. The purpose of this study was to assess whether this polymorphism contributes to the variability in response to tramadol/acetaminophen combination tablets (Ultracet) for treating oxaliplatin‐induced painful neuropathy.

METHODS:

A total of 96 patients with adenocarcinoma of the colon or rectum (n = 84), or stomach (n = 12) who had developed oxaliplatin‐induced painful neuropathy were enrolled. Ultracet was administered at 1 tablet every 6 hours, and pain was assessed and scored using a visual analog scale (VAS). The OPRM1 A118G polymorphism was examined with a polymerase chain reaction‐direct sequencing method.

RESULTS:

The allelic frequency of variant (118G) allele was 39.6%, and the prevalence of OPRM1‐118 AA, AG, and GG genotypes was 31.3% (n = 30), 58.3% (n = 56), and 10.4% (n = 10), respectively. For all patients, the mean pre‐treatment and post‐treatment VAS scores were 3.1 and 2.1, respectively (P < .001). Patients with AA genotype had a better analgesic effect than those with G allele variants (AG or GG genotypes). Pre‐treatment and post‐treatment VAS scores for patients with G allele variants were 3.1 and 2.6, respectively; however, for patients with AA genotype, pre‐treatment and post‐treatment VAS scores were 3.0 and 0.9, respectively (P < .001). The requirement for rescue analgesia was also higher for patients with G allele variants (P = .01).

CONCLUSIONS:

These data suggest that Ultracet is effective in the management of oxaliplatin‐induced painful neuropathy. A118G polymorphism of OPRM1, by altered function of the mu‐opioid receptor and consequential analgesic effect on opioid agents, could be a key determinant for decreased response to Ultracet. Cancer 2011;. © 2011 American Cancer Society.     

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.     

Lung cancer susceptibility and prognosis associated with polymorphisms in the nonhomologous end‐joining pathway genes

BACKGROUND:

Nonsmall cell lung cancer (NSCLC) frequently exhibits genomic instability, such as high fractional allelic loss (FAL). Genomic instability may result from unrepaired or misrepaired double‐strand breaks (DSBs). The authors of this report postulated that polymorphisms in genes of the nonhomologous end‐joining (NHEJ) pathway, which is the major DSB repair pathway in mammalian cells, may modulate lung cancer susceptibility and prognosis.

METHODS:

Patients with NSCLC (n = 152) and a group of appropriate age‐matched and sex‐matched controls (n = 162) were subjected to genotype analysis of the NHEJ pathway genes x‐ray repair complementing defective repair in Chinese hamster cells 6 (Ku70) (reference single nucleotide polymorphism number [rs] 2267437), x‐ray repair complementing defective repair in Chinese hamster cells 5 (Ku80) (rs3835), x‐ray repair complementing defective repair in Chinese hamster cells 4 (XRCC4) (rs1805377), and DNA ligase IV (LIG4) (rs1805388). The gene‐gene interaction (joint effect), genotype‐environmental (ie, smoking) correlation, and genotype‐phenotype (ie, FAL) correlation were examined. The Kaplan‐Meier method and log‐rank tests were used to assess the prognostic effect.

RESULTS:

There was a significant association between the XRCC4 and LIG4 genotypes with NSCLC risk in an analysis of individual polymorphism associations, and the risk of NSCLC increased further in a combined analysis of multiple polymorphisms (adjusted odds ratio [OR], 8.74). The patients who had a homozygous variant guanine/guanine genotype of the XRCC4 gene had a poorer prognosis compared with other patients (P = .015). There was a significant difference between the patient smokers and controls for XRCC4 (adjusted OR, 2.67) and LIG4 (adjusted OR, 2.04). In addition, polymorphisms in XRCC4 and LIG4 were linked significantly with patients who had high FAL (adjusted OR, 2.03‐3.84).

CONCLUSIONS:

To the authors' knowledge, this is the first nested case‐control study to demonstrate a significant association between the polymorphisms of genes in the NHEJ pathway and lung cancer susceptibility and prognosis. The results may be useful for risk assessment and disease monitoring of patients with NSCLC. Cancer 2009. © 2009 American Cancer Society.     

Wnt antagonist gene polymorphisms and renal cancer

BACKGROUND:

Epigenetic silencing of several wingless‐type mouse mammary tumor virus integration site (Wnt) pathway‐related genes has been reported in renal cancer. Except for the T‐cell factor 4 gene TCF4, there are no reports regarding Wnt pathway gene polymorphisms in renal cancer. Therefore, the authors of this report hypothesized that the polymorphisms in Wnt signaling genes may be risk factors for renal cancer.

METHODS:

In total, 210 patients (145 men and 65 women) with pathologically confirmed renal cell carcinoma (RCC) and 200 age‐matched and sex‐matched control individuals were enrolled in this study. We genotyped 14 single nucleotide polymorphisms (SNPs) in 6 genes. including Dickkopf 2 (DKK2) (reference SNP identification number 17037102 [rs17037102], rs419558, and rs447372), DKK3 (rs3206824, rs11022095, rs1472189, rs7396187, and rs2291599), DKK4 (rs2073664), secreted frizzled‐related protein 4 (sFRP4) (rs1802073 and rs1802074), mothers against decapentaplegic homolog (SMAD) family member 7 or SMAD7 (rs12953717), and disheveled associated activator of morphogenesis 2 or DAAM2 (rs6937133 and rs2504106) using polymerase chain reaction‐restriction fragment length polymorphism analysis and direct sequencing in the patients with RCC and in the healthy, age‐matched control group. The relations also were tested between these polymorphisms and clinicopathologic data, including sex, tumor grade, tumor stage, lymph node involvement, distant metastasis, and overall survival.

RESULTS:

A significant decrease in the frequency of the guanine/adenine (G/A) + A/A genotypes in the DKK3 codon 335 rs3206824 was observed in the patients with RCC compared with the control group. The frequency of the rs3206824 (G/A) A‐rs7396187 (guanine/cytosine [G/C]) C haplotype was significantly lower in patients with RCC compared with other haplotypes. In addition, DKK3 rs1472189 cytosine/thymine (C/T) was associated with distant metastasis, and, DKK2 rs17037102 G‐homozygous patients had a decreased risk for death in multivariate Cox regression analysis.

CONCLUSIONS:

To the authors' knowledge, this is the first report documenting that DKK3 polymorphisms are associated with RCC and that the DKK2 rs17037102 polymorphism may be a predictor for survival in patients with RCC after radical nephrectomy. Cancer 2009. © 2009 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.     

Effects of MDM2 promoter polymorphisms and p53 codon 72 polymorphism on risk and age at onset of squamous cell carcinoma of the head and neck

Both p53 tumor suppressor and murine double minute 2 (MDM2) oncoprotein are crucial in carcinogenesis. We hypothesized that MDM2 promoter single nucleotide polymorphisms (SNPs) SNP309 T > G, A2164G, and p53 codon 72 are associated with risk and age at onset of squamous cell carcinoma of head and neck (SCCHN). We genotyped these SNPs in a study of 1,083 Caucasian SCCHN cases and 1,090 cancer-free controls. Although none of these SNPs individually had a significant effect on risk of SCCHN, nor did their combined putative risk genotypes (i.e., MDM2 SNP309 GT + GG, 2164 AA, and p53 codon 72 CC), we found that individuals with two to three risk genotypes had significantly increased risk of non-oropharyngeal cancer (OR = 1.42; 95% CI = 1.07-1.88). This increased risk was more pronounced among young subjects, men, smokers, and drinkers. In addition, female patients carrying the MDM2 SNP309 GT and GG genotypes showed a 3-yr (56.7 yr) and 9-yr (51.2 yr) earlier age at onset of non-oropharyngeal cancer (P(trend) = 0.007), respectively, compared with those carrying the TT genotype (60.1 yr). The youngest age (42.5 yr) at onset of non-oropharyngeal cancer was observed in female patients with the combined MDM2 SNP309 GG and p53 codon 72 CC genotypes. The findings suggest that MDM2 SNP309, A2164G, and p53 codon 72 SNPs may collectively contribute to non-oropharyngeal cancer risk and that MDM2 SNP309 individually or in combination with p53 codon 72 may accelerate the development of non-oropharyngeal cancer in women. Further studies with large sample sizes are warranted to validate these results.     

Pemetrexed in combination with cisplatin versus cisplatin monotherapy in patients with recurrent or metastatic head and neck cancer: Final results of a randomized, double-blind, placebo-controlled, phase 3 study

BACKGROUND:

Recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN) is associated with poor survival. Platinum‐based chemotherapy is often a first‐line treatment. Pemetrexed has shown single‐agent activity in SCCHN and in combination with cisplatin for other tumors. This trial examined the efficacy of pemetrexed‐cisplatin for SCCHN.

METHODS:

In a double‐blind phase 3 trial, patients with recurrent or metastatic SCCHN and no prior systemic therapy for metastatic disease were randomized to pemetrexed (500 mg/m²) plus cisplatin (75 mg/m²; n = 398) or placebo plus cisplatin (75 mg/m²; n = 397) to assess overall survival (OS) and secondary endpoints.

RESULTS:

Median OS was 7.3 months in the pemetrexed‐cisplatin arm and 6.3 months in the placebo‐cisplatin arm (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.75‐1.02; P = .082). Median progression‐free survival (PFS, months) was similar in both treatment arms (pemetrexed‐cisplatin, 3.6; placebo‐cisplatin, 2.8; HR, 0.88; 95% CI, 0.76‐1.03; P = .166). Among patients with performance status 0 or 1, pemetrexed‐cisplatin (n = 347) led to longer OS and PFS than placebo‐cisplatin (n = 343; 8.4 vs 6.7 months; HR, 0.83; P = .026; 4.0 vs 3.0 months; HR, 0.84; P = .044, respectively). Among patients with oropharyngeal cancers, pemetrexed‐cisplatin (n = 86) resulted in longer OS and PFS than placebo‐cisplatin (n = 106; 9.9 vs 6.1 months; HR, 0.59; P = .002; 4.0 vs 3.4 months; HR, 0.73; P = .047, respectively). Pemetrexed‐cisplatin toxicity was consistent with studies in other tumors.

CONCLUSIONS:

Pemetrexed‐cisplatin compared with placebo‐cisplatin did not significantly improve survival for the intent‐to‐treat population. However, in a prespecified subgroup analysis, pemetrexed‐cisplatin showed OS and PFS advantage for patients with performance status 0 or 1 or oropharyngeal cancers. Cancer 2012. © 2012 American Cancer Society.