Identification of novel germline polymorphisms governing capecitabine sensitivity

BACKGROUND:

Capecitabine, an oral 5‐fluorouracil (5‐FU) prodrug, is widely used in the treatment of breast, colorectal, and gastric cancers. To guide the selection of patients with potentially the greatest benefit of experiencing antitumor efficacy, or, alternatively, of developing toxicities, identifying genomic predictors of capecitabine sensitivity could permit its more informed use.

METHODS:

The objective of this study was to perform capecitabine sensitivity genome‐wide association studies (GWAS) using 503 well genotyped human cell lines from individuals representing multiple different world populations. A meta‐analysis that included all ethnic populations then enabled the identification of novel germline determinants (single nucleotide polymorphisms [SNPs]) of capecitabine susceptibility.

RESULTS:

First, an intrapopulation GWAS of Caucasian individuals identified reference SNP 4702484 (rs4702484) (within adenylate cyclase 2 [ADCY2]) at a level reaching genome‐wide significance (P = 5.2 × 10^?8). This SNP is located upstream of the 5 methyltetrahydrofolate‐homocysteine methyltransferase reductase (MTRR) gene, and it is known that the enzyme for MTRR is involved in the methionine‐folate biosynthesis and metabolism pathway, which is the primary target of 5‐FU‐related compounds, although the authors were unable to identify a direct relation between rs4702484 and MTRR expression in a tested subset of cells. In the meta‐analysis, 4 SNPs comprised the top hits, which, again, included rs4702484 and 3 additional SNPs (rs8101143, rs576523, and rs361433) that approached genome‐wide significance (P values from 1.9 × 10^?7 to 8.8 × 10^?7). The meta‐analysis also identified 1 missense variant (rs11722476; serine to asparagine) within switch/sucrose nonfermentable‐related, matrix‐associated, actin‐dependent regulator of chromatin (SMARCAD1), a novel gene for association with capecitabine/5‐FU susceptibility.

CONCLUSIONS:

Toward the goal of individualizing cancer chemotherapy, the current study identified novel SNPs and genes associated with capecitabine sensitivity that are potentially informative and testable in any patient regardless of ethnicity. Cancer 2011. © 2011 American Cancer Society.     

Interactions between environmental factors and polymorphisms in angiogenesis pathway genes in esophageal adenocarcinoma risk: a case-only study

BACKGROUND:

Gastroesophageal reflux disease (GERD), higher body mass index (BMI), smoking, and genetic variants in angiogenic pathway genes have been individually associated with increased risk of esophageal adenocarcinoma. However, how angiogenic gene polymorphisms and environmental factors jointly affect esophageal adenocarcinoma development remains unclear.

METHODS:

By using a case‐only design (n = 335), the authors examined interactions between 141 functional/tagging angiogenic single nucleotide polymorphisms (SNPs) and environmental factors (GERD, BMI, smoking) in modulating esophageal adenocarcinoma risk. Gene‐environment interactions were assessed by a 2‐step approach. First, the authors applied random forest to screen for important SNPs that had either main or interaction effects. Second, they used case‐only logistic regression to assess the effects of gene‐environment interactions on esophageal adenocarcinoma risk, adjusting for covariates and false‐discovery rate.

RESULTS:

Random forest analyses identified 3 sets of SNPs (17 SNPs‐GERD, 26 SNPs‐smoking, and 34 SNPs‐BMI) that had the highest importance scores. In subsequent logistic regression analyses, interactions between 2 SNPs (rs2295778 of HIF1AN, rs13337626 of TSC2) and GERD, 2 SNPs (rs2295778 of HIF1AN, rs2296188 of VEGFR1) and smoking, and 7 SNPs (rs2114039 of PDGRFA, rs2296188 of VEGFR1, rs11941492 of VEGFR1, rs17708574 of PDGFRB, rs7324547 of VEGFR1, rs17619601 of VEGFR1, and rs17625898 of VEGFR1) and BMI were significantly associated with esophageal adenocarcinoma development (all false‐discovery rates ≤0.10). Moreover, these interactions tended to have SNP dose‐response effects for increased esophageal adenocarcinoma risk with increasing number of combined risk genotypes.

CONCLUSIONS:

These findings suggest that genetic variations in angiogenic genes may modify esophageal adenocarcinoma susceptibility through interactions with environmental factors in an SNP dose‐response manner. Cancer 2012;. © 2011 American Cancer Society.     

The presence of aberrant DNA methylation in noncancerous esophageal mucosae in association with smoking history

BACKGROUND:

Esophageal squamous cell carcinomas (ESCCs) tend to have multiple primary lesions, and it is believed that they arise from background mucosae with accumulation of genetic/epigenetic alterations. In this study, the objective was to elucidate the effects of smoking and drinking on the accumulation of epigenetic alterations in background mucosae.

METHODS:

Genes that are silenced in human ESCCs were searched for by treating 3 ESCC cell lines with the demethylating agent, 5‐aza‐2′‐deoxycytidine and performing oligonucleotide microarrays. Methylation levels were analyzed by quantitative methylation‐specific polymerase chain reaction analysis of 60 ESCCs and their corresponding background mucosae.

RESULTS:

Forty‐seven genes were identified as methylation‐silenced in at least 1 of the 3 ESCC cell lines, and 14 of those genes (claudin 6 [CLDN6]; G protein‐coupled receptor 158 [GPR158]; homeobox A9 [HOXA9]; metallothionein 1M [MT1M]; neurofilament, heavy polypeptide 200 kDa [NEFH]; plakophilin 1 [PKP1]; protein phosphatase 1, regulatory [inhibitor] subunit 14A [PPP1R14A]; pyrin domain and caspase recruitment domain containing [PYCARD]; R‐spondin family, member 4 [RSPO4]; testis‐specific protein, Y‐encoded–like 5 [TSPYL5]; ubiquitin carboxyl‐terminal esterase L1 [UCHL1]; zinc‐finger protein 42 homolog [ZFP42]; zinc‐finger protein interacting with K protein 1 homolog [ZIK1]; and zinc‐finger and SCAN domain containing 18 [ZSCAN18]) were used as markers. In the background mucosae, methylation levels of 5 genes (HOXA9, MT1M, NEFH, RSPO4, and UCHL1) had significant correlations with smoking duration (ρ = .268; P = .044; ρ = .405; P = .002; ρ = .285; P = .032; ρ = .300; P = .024; and ρ = .437; P = .001, respectively). In contrast, an inverse correlation between PYCARD methylation levels and alcohol intake was observed (ρ = ?.334, P = .025) among individuals with the inactive aldehyde dehydrogenase 2 (ALDH2) genotype.

CONCLUSIONS:

The current results suggested that ESCCs developed from an epigenetic field for cancerization, which was induced by exposure to carcinogenic factors, such as tobacco smoking. The epigenetic field defect will be a novel target for risk diagnosis and prevention of ESCCs. Cancer 2009. © 2009 American Cancer Society.     

Functional polymorphisms of circadian positive feedback regulation genes and clinical outcome of Chinese patients with resected colorectal cancer

BACKGROUND:

Previous studies have demonstrated that circadian genes play a role in the development and progression of many cancers. This study aims to assess the effects of single nucleotide polymorphisms (SNPs) in circadian genes on recurrence and survival of colorectal cancer (CRC) patients.

METHODS:

Nine functional SNPs in 3 genes (CLOCK, NPAS2, and BMAL1) on the circadian positive feedback loop were selected and genotyped using the Sequenom iPLEX genotyping system in a cohort of 411 resected Chinese CRC patients. Multivariate Cox proportional hazards model and Kaplan‐Meier curve were used for the prognosis analysis.

RESULTS:

The authors identified 2 SNPs in the CLOCK gene to be significantly associated with CRC overall survival. SNP rs3749474 exhibited a significant association with survival of CRC patients in the additive model (hazard ratio [HR], 0.55; 95% confidence interval [CI], 0.37‐0.81; P = .003). In addition, patients carrying the heterozygous variant of rs1801260 had significantly increased overall survival compared with those carrying homozygous wild‐type genotype (HR, 0.31; 95% CI, 0.11‐0.88; P = .03). Findings from functional assay provided further biological support for these significant associations. Stratified analysis found no modifying effect of chemotherapy on the prognostic significance of both SNPs. Moreover, we observed cumulative effects of these 2 SNPs on CRC overall survival (P for trend = .01). Compared with patients carrying no unfavorable genotypes, those carrying 2 unfavorable genotypes had a 2.92‐fold increased risk of death (P = .03).

CONCLUSIONS:

The results suggest for the first time that CLOCK gene polymorphisms may serve as an independent prognostic marker for CRC patients. Cancer 2012;. © 2011 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.     

Comparison of adverse events during 5-fluorouracil versus 5-fluorouracil/oxaliplatin adjuvant chemotherapy for stage III colon cancer: a population-based analysis

BACKGROUND:

In clinical trials, combined 5‐fluorouracil (5FU) plus oxaliplatin improves the survival of patients who have resected, stage III colon cancer with manageable toxicity. However, the tolerability of this in the general population of patients with colon cancer is uncertain.

METHODS:

Adverse outcomes were compared in patients with stage III colon cancer who received either 5FU or 5FU/oxaliplatin within 120 days of undergoing resection versus a control group of patients with stage II colon cancer who did not receive chemotherapy in the Surveillance, Epidemiology, and End Results (SEER)‐Medicare database and in data from the New York State Cancer Registry linked to Medicare and Medicaid. Hospitalizations, emergency room (ER) visits, and outpatient adverse events (AEs) were measured in claims from 30 days to 9 months after patients underwent resection. Multiple logistic regression was used to calculate adjusted odds ratios of events by treatment. Propensity score matching was used to minimize selection bias.

RESULTS:

Adverse outcomes were more frequent for chemotherapy recipients. AE rates were higher in patients who received 5FU/oxaliplatin (81%) compared with patients who received 5FU alone (72%), in the SEER‐Medicare data. The effect of oxaliplatin on AEs was greater in older patients: The odds ratio was 2.10 (95% confidence interval, 1.53‐2.87) for patients aged ≥75 years versus 1.75 (95% confidence interval, 1.39‐2.21) for patients aged <75 years. ER use was high in Medicaid patients (83% of those who received chemotherapy), but neither ER use nor hospitalization was increased by oxaliplatin. The 60‐day mortality rate was 1% to 3% for patients who received 5FU alone and 1% to 2% for patients who received combined 5FU/oxaliplatin.

CONCLUSIONS:

The incremental harms of adjuvant chemotherapy with 5FU/oxaliplatin versus 5FU alone were modest in patients with stage III colon cancer who were insured by Medicare and Medicaid. The additional harms in patients aged ≥75 years largely were restricted to outpatient events and did not extend to an increased rate of hospitalization or early death. Cancer 2012. © 2012 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.     

Genetic polymorphisms in obesity-related genes and endometrial cancer risk

BACKGROUND:

Obesity is associated with circulating levels of adiponectin and leptin and endometrial cancer risk. Little is known about whether single nucleotide polymorphisms (SNPs) in the genes that encode adiponectin (ADIPOQ), leptin (LEP), adiponectin receptor 1 (ADIPOR1), adiponectin receptor 2 (ADIPOR2), and leptin receptor (LEPR) are associated with endometrial cancer.

METHODS:

The authors selected 87 tagging SNPs to capture common genetic variants in these 5 genes. These SNPs were evaluated in 1028 endometrial cancer cases and 1932 community controls recruited from Chinese women. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS:

Three of the 10 SNPs evaluated in the ADIPOQ gene were significantly associated with reduced cancer risk. The OR for women homozygous for the minor allele (A/A) for rs3774262 was 0.68 (95% CI, 0.48‐0.97) compared with women homozygous for the major allele (G/G). Similar results were found for SNPs rs1063539 and rs12629945 in ADIPOQ, which were in linkage disequilibrium with rs3774262. These associations became nonsignificant after Bonferroni correction was applied. Controls with the minor allele A at rs3774262 had lower weight, smaller waist and hip circumferences, and lower body mass index than controls with the major allele G (all P < .05). Women homozygous for the minor allele (T/T) of rs2071045 in the LEP gene also had significantly lower risk (OR, 0.70; 95% CI, 0.54‐0.90) than women homozygous for the major allele (C/C). No other SNPs in the LEP, ADIPOR1, ADIPOR2, or LEPR genes were found to be associated with cancer risk.

CONCLUSIONS:

Although a chance finding cannot be ruled out, the consistency of findings for gene‐endometrial cancer risk and gene‐obesity measurements suggests that genetic polymorphisms in the ADIPOQ gene may play a role in endometrial cancer development. Cancer 2011. © 2011 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.     

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.     

Identification of polymorphisms in ultraconserved elements associated with clinical outcomes in locally advanced colorectal adenocarcinoma

BACKGROUND:

Ultraconserved elements (UCEs) are noncoding genomic sequences that completely identical among human, mouse, and rat species and harbor critical biologic functions. The authors hypothesized that single nucleotide polymorphisms (SNPs) within UCEs are associated with clinical outcomes in patients with colorectal cancer (CRC).

METHODS:

Forty‐eight SNPs within UCEs were genotyped in 662 patients with stage I through III CRC. The associations between genotypes and recurrence and survival were analyzed in patients with stage II or III CRC who received fluoropyrimidine‐based adjuvant chemotherapy using a training and validation design. The training set included 115 patients with stage II disease and 170 patients with stage III disease, and the validation set included 88 patients with stage II disease and 112 patients with stage III disease.

RESULTS:

Eight SNPs were associated with clinical outcomes stratified by disease stage. In particular, for patients with stage II CRC who had at least 1 variant allele of reference SNP sequence 7849 (rs7849), a consistent association with increased recurrence risk was observed in the training set (hazard ratio [HR], 2.39; 95% confidence interval [CI], 1.04‐5.52), in the replication set (HR, 3.70; 95% CI, 1.42‐9.64), and in a meta‐analysis (HR, 2.89; 95% CI, 1.54‐5.41). Several other SNPs were significant in the training set but not in the validation set. These included rs2421099, rs16983007, and rs10211390 for recurrence and rs6590611 for survival in patients with stage II disease; and SNPs rs6124509 and rs11195893 for recurrence in patients with stage III disease. In addition, a significant cumulative effect was observed of multiple risk genotypes and potential gene‐gene interactions on recurrence risk.

CONCLUSIONS:

To the authors' knowledge, this is the first study to evaluate the association between SNPs within UCEs and clinical outcome in patients with CRC. The results suggested that SNPs within UCEs may be valuable prognostic biomarkers for patients with locally advanced CRC who receive 5‐fluorouracil–based chemotherapy. Cancer 2012. © 2012 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.     

Genetic variation in innate immunity and inflammation pathways associated with lung cancer risk

BACKGROUND:

Pulmonary inflammation may contribute to lung cancer etiology. The authors conducted a broad evaluation of the association of single nucleotide polymorphisms (SNPs) in innate immunity and inflammation pathways with lung cancer risk and conducted comparisons with a lung cancer genome‐wide association study (GWAS).

METHODS:

In total, 378 patients with lung cancer (cases) and a group of 450 controls from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial were included. A proprietary oligonucleotide pool assay was used to genotype 1429 SNPs. Odds ratios and 95% confidence intervals were estimated for each SNP, and P values for trend (P_trend) were calculated. For statistically significant SNPs (P_trend < .05), the results were replicated with genotyped or imputed SNPs in the GWAS, and P values were adjusted for multiple testing.

RESULTS:

In the PLCO analysis, a significant association was observed between lung cancer and 81 SNPs located in 44 genes (P_trend < .05). Of these 81 SNPS, there was evidence for confirmation in the GWAS for 10 SNPs. However, after adjusting for multiple comparisons, the only SNP that retained a significant association with lung cancer in the replication phase was reference SNP rs4648127 (nuclear factor of kappa light polypeptide gene enhancer of B‐cells 1 [NFKB1]) (multiple testing‐adjusted P_trend = .02). The cytosine‐thymine (CT)/TT genotype of NFKB1 was associated with reduced odds of lung cancer in the PLCO study (odds ratio, 0.56; 95% confidence interval, 0.37‐0.86) and the in the GWAS (odds ratio, 0.79; 95% confidence interval, 0.69‐0.90).

CONCLUSIONS:

A significant association was observed between a variant in the NFKB1 gene and the risk of lung cancer. The current findings add to evidence implicating inflammation and immunity in lung cancer etiology. Cancer 2012. Published 2012 by the American Cancer Society.     

Pharmacogenetic predictors of severe peripheral neuropathy in colon cancer patients treated with oxaliplatin-based adjuvant chemotherapy: a GEMCAD group study

BackgroundOxaliplatin-based chemotherapy (CT), widely used as adjuvant therapy for stage III and selected high-risk stage II colon cancer (CC) patients, is often associated with cumulative peripheral neuropathy. Our aim is to identify single-nucleotide polymorphisms (SNPs) in genes involved in oxaliplatin metabolism, DNA repair mechanisms, cell cycle control, detoxification or excretion pathways to predict severe (grade 2–3) oxaliplatin-induced peripheral neuropathy (OXPN) among CC patients treated with oxaliplatin and fluoropyrimidine-based adjuvant CT.Patients and methodsGenomic DNA was extracted from formalin-fixed-paraffin-embedded peritumoral samples from 206 high-risk stage II and stage III CC patients receiving oxaliplatin-based adjuvant CT from January 2004 to December 2009. Genotyping was carried out for 34 SNPs in 15 genes using MassARRAY (SEQUENOM) technology. A total of 181 stage II–III CC patients treated with the same CT regimens were enrolled as a validation set.ResultsThe rs2230641 cyclin H (CCNH) rs2230641 C/C [odd ratio (OR) = 5.03, 95% confidence interval (CI) 1.061–2.41, P = 0.042] and the ATP-binding cassette subfamily G, member 2 (ABCG2) rs3114018 A/A genotypes (OR = 2.67; 95% CI 0.95–4.41; P = 0.059) were associated with a higher risk of severe OXPN. In addition, patients harboring the combination of CCNH C/C and/or the ABCG2 rs3114018 A/A genotypes had a higher risk of grade 2–3 OXPN than those with the CCNH any T and ABCG2 any C genotypes (37.73% versus 19.42%; OR = 2.46; 95% CI 1.19–5.07; P = 0.014) in the logistic regression analysis using age, gender, adjuvant CT regimen and cumulative dose of oxaliplatin as covariates. The ability to predict severe OXPN of this combined analysis was independently validated in the second cohort (58% versus 33.33%; OR = 2.99; 95% CI 1.45–6.13; P = 0.002).ConclusionsOur results suggest that SNPs in CCNH and ABCG2 can modulate the development of severe OXPN among stage II–III CC patients who received oxaliplatin-based CT, thus enabling the individualization of adjuvant treatment.     

Genetic variants in one‐carbon metabolism‐related genes contribute to NSCLC prognosis in a Chinese population

BACKGROUND:

One‐carbon metabolism plays a critical role in DNA methylation and DNA synthesis. Variants of genes involved in one‐carbon metabolism may result in aberrant methylation and/or DNA synthesis inhibition, and ultimately modulate the initiation and progression of tumors. In this study, the authors hypothesized that polymorphisms in one‐carbon metabolism‐related genes may contribute to the prognosis of nonsmall cell lung cancer (NSCLC).

METHODS:

The authors screened 57 potentially functional single nucleotide polymorphisms (SNPs) from 11 candidate genes involved in one‐carbon metabolism and genotyped them in a cohort of 568 NSCLC patients by using Illumina Golden Gate platform. The Kaplan‐Meier method with log‐rank test and Cox proportional hazards model were used for survival analyses.

RESULTS:

Variant alleles were significantly associated with favorable survivals of NSCLC for MTR rs3768160 A>G (allelic hazards ratio [HR], 0.78; 95% confidence interval [CI], 0.62‐0.98), MTRR rs2966952 G>A (allelic HR, 0.84; 95% CI, 0.71‐0.99) and DHFR rs1650697 G>A (allelic HR, 0.83; 95% CI, 0.70‐0.99) and with unfavorable prognosis for MTHFD1 rs1950902 G>A with borderline significance (allelic HR, 1.18; 95% CI, 0.99‐1.40). In addition, the combined genotypes of these four SNPs showed a locus‐dosage effect on NSCLC survival (P_trend = 6.9 × 10^?5). In the final multivariate Cox regression model, combined genotypes based on 3 categories may be an independent prognostic factor for NSCLC with adjusted trend HR of 0.78 (95% CI, 0.66‐0.92).

CONCLUSION:

Genetic variants in one‐carbon metabolism pathway may be candidate biomarkers for NSCLC prognosis. Cancer 2010. © 2010 American Cancer Society.     

Clinical efficacy of local targeted chemotherapy for triple-negative breast cancer

Background

The aim of the study was to evaluate the clinical efficacy of superselective intra-arterial targeted neo-adjuvant chemotherapy in the treatment of estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and human epidermal growth factor receptor 2 (HER2)-negative (triple-negative) breast cancer.

Patients and methods.

A total of 47 triple-negative breast cancer patients (29 at stage II, 13 at stage III and 5 at stage IV) were randomly assigned to two groups: targeted chemotherapy group (n=24) and control group (n=23). Patients in the targeted chemotherapy group received preoperative superselective intra-arterial chemotherapy with CEF regimen (C: cyclophosphamide [600 mg/m²]; E: epirubicin [90 mg/m²]; F: 5-fluorouracil [600 mg/m²]), and those in the control group received routine neoadjuvant chemotherapy with CEF. The duration of the treatment, changes in lesions and the prognosis were determined.

Results

The average course of the treatment was 15 days in the targeted chemotherapy group which was significantly shorter than that in the control group (31 days) (P<0.01). The remission rate of lesions was 91.6% in the targeted chemotherapy group and 60.9% in the control group, respectively. Among these patients, 9 died within two years, including 2 (both at IV stage) in the targeted chemotherapy group and 7 (2 at stage II, 4 at stage III and 1 at stage IV) in the control group.

Conclusions

As an neoadjuvant therapy, the superselective intra-arterial chemotherapy is effective for triple-negative breast cancer, with advantages of the short treatment course and favourable remission rates as well as prognoses.     

Association Between CASP8 and CASP10 Polymorphisms and Toxicity Outcomes With Platinum‐Based Chemotherapy in Chinese Patients With Non‐Small Cell Lung Cancer

Caspase‐8 and caspase‐10 play crucial roles in both cancer development and chemotherapy efficacy. In this study, we aimed to comprehensively assess single nucleotide polymorphisms (SNPs) of the caspase‐8 (CASP8) and caspase‐10 (CASP10) genes in relation to toxicity outcomes with first‐line platinum‐based chemotherapy in patients with advanced non‐small cell lung cancer (NSCLC). We genotyped 13 tag SNPs of CASP8 and CASP10 in 663 patients with advanced NSCLC treated with platinum‐based chemotherapy regimens. Associations between SNPs and chemotherapy toxicity outcomes were identified in a discovery set of 279 patients and then validated in an independent set of 384 patients. In both the discovery and validation sets, variant homozygotes of CASP8 rs12990906 and heterozygotes of CASP8 rs3769827 and CASP10 rs11674246 and rs3731714 had a significantly lower risk for severe toxicity overall. However, only the association with the rs12990906 variant was replicated in the validation set for hematological toxicity risk. In a stratified analysis, we found that some other SNPs, including rs3769821, rs3769825, rs7608692, and rs12613347, were significantly associated with severe toxicity risk in some subgroups, such as in nonsmoking patients, patients with adenocarcinoma, and patients treated with cisplatin combinations. Consistent results were also found in haplotype analyses. Our results provide novel evidence that polymorphisms in CASP8 and CASP10 may modulate toxicity outcomes in patients with advanced NSCLC treated with platinum‐based chemotherapy. If validated, the findings will facilitate the genotype‐based selection of platinum‐based chemotherapy regimens.     

Is resection of colorectal liver metastases after a second‐line chemotherapy regimen justified?

BACKGROUND:

Patient outcomes following resection of colorectal liver metastases (CLM) after second‐line chemotherapy regimen is unknown.

METHODS:

From August 1998 to June 2009, data from 1099 patients with CLM were collected prospectively. We retrospectively analyzed outcomes of patients who underwent resection of CLM after second‐line (2 or more) chemotherapy regimens.

RESULTS:

Sixty patients underwent resection of CLM after 2 or more chemotherapy regimens. Patients had advanced CLM (mean number of CLM ± standard deviation, 4 ± 3.5; mean maximum size of CLM, 5 ± 3.2 cm) and had received 17 ± 8 cycles of preoperative chemotherapy. In 54 (90%) patients, the switch from the first regimen to another regimen was motivated by tumor progression or suboptimal radiographic response. All patients received irinotecan or oxaliplatin, and the majority (42/60 [70%]) received a monoclonal antibody (bevacizumab or cetuximab) as part of the last preoperative regimen. Postoperative morbidity and mortality rates were 33% and 3%, respectively. At a median follow‐up of 32 months, 1‐year, 3‐year, and 5‐year overall survival rates were 83%, 41%, and 22%, respectively. Median chemotherapy‐free survival after resection or completion of additional chemotherapy administered after resection was 9 months (95% confidence interval, 4‐14 months). Synchronous (vs metachronous) CLM and minor (vs major) pathologic response were independently associated with worse survival.

CONCLUSIONS:

Resection of CLM after a second‐line chemotherapy regimen was found to be safe and was associated with a modest hope for definitive cure. This approach represents a viable option in patients with advanced CLM. Cancer 2011;. © 2011 American Cancer Society.     

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.