A case-control study of the <Emphasis Type="Italic">HER2</Emphasis> Ile655Val polymorphism in relation to risk of invasive breast cancer

Background  

Overexpression of the HER2 proto-oncogene in human cancer cells has been associated with a poor prognosis, and survival improves with therapy targeting the HER2 gene. Animal studies and protein modeling suggest that the Ile655Val polymorphism located in the transmembrane domain of the HER2 protein might influence breast cancer development by altering the efficiency of homodimerization.     

HER2 Ile655Val polymorphism contributes to breast cancer risk: evidence from 27 case–control studies

Proto-oncogene HER2 (also known as erbB-2 or neu) plays an important role in the carcinogenesis and the prognosis of breast cancer. Many epidemiological studies have been conducted to explore the association between the HER2 Ile655Val polymorphism and breast cancer risk. However, inconsistency existed in the results. Therefore, we performed a meta-analysis of 27 published case–control studies including 11,504 cases and 12,538 controls. We assessed the strength of the association by crude odds ratios (ORs) with 95% confidence intervals (CIs) and reached a result that HER2 Ile655Val polymorphism was associated with an increased breast cancer risk in overall populations (for Ile/Val vs. Ile/Ile: OR = 1.05, 95% CI = 1.00–1.12, P = 0.07 for heterogeneity; for the dominant model Ile/Val + Val/Val vs. Ile/Ile: OR = 1.10, 95% CI = 1.01–1.20, P = 0.01 for heterogeneity). In subgroup analysis by ethnicity, we found a significant association among Africans (for Val/Val vs. Ile/Ile: OR = 8.78, 95% CI = 1.94–39.72, P = 0.35 for heterogeneity; for the recessive model Val/Val vs. Ile/Val +Ile/Ile: OR = 8.60, 95% CI = 1.92–38.48, P = 0.31 for heterogeneity) and Asians (for Ile/Val vs. Ile/Ile: OR = 1.18, 95% CI = 1.01–1.39, P = 0.41 for heterogeneity; for the dominant model Val/Val + Ile/Val vs. Ile/Ile: OR = 1.18, 95% CI = 1.01–1.38, P = 0.27 for heterogeneity). In conclusion, our meta-analysis suggests that HER2 Ile 655Val polymorphism may contribute to breast cancer risk.     

A systemic review of glutathione S-transferase P1 Ilel05Val polymorphism and colorectal cancer risk

Objectives： To investigate the correlation between glutathione S-transferase P1 （GSTP1） Ilel05Val polymorphism and colorectal cancer （CRC） risk. Methods： Studies were identified to investigate the association between GSTP1 Ilel05Val polymorphism and CRC risk. Systematic computerized searches of the PubMed, Chinese National Knowledge Infrastructure, WANFANG and SinoMed were performed. Summary odds ratios （OR） and 95% confidence intervals （95 % CI） were used to measure GSTP 1 Ile 105Val polymorphisms and CRC risk. Results： A total of 23 retrospective studies were included in the meta-analysis. During all studies including 6,981 cases and 8,977 controls, sample sizes ranged from 146 to 2,144. Overall, the pooled results revealed that lie 105Val polymorphism was not associated with CRC risk and confused results were found in subgroup analyses. Further meta-analyses were conducted after excluding low-quality studies. GSTP1 Ilel05Val is associated with increased risk of CRC limited in studies with matched control. There was no significant heterogeneity in all genetic comparisons, but heterogeneity existed in subgroup analyses of heterozygous and dominant comparisons. The meta-regression analyses indicated that matched controls were the significant factor influencing between-study heterogeneity in all possible influential factors including published year, ethnicity, source of control, sample size, Hardy-Weinberg equilibrium （HWE） in control and matched controls. Sensitivity analysis revealed the pooled ORs were not changed before and after removal of each single study in all genetic comparisons, indicating the robustness of the results. Conclusions： GSTP1 Ilel05Val might be associated with increased risk of CRC. However, more high- quality case-control studies should be performed to confirm the authenticity of our conclusion.     

GST (GSTM1, GSTT1, and GSTP1) polymorphisms in the genetic susceptibility of Turkish patients to cervical cancer

Objective

This work investigates the role of glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1), and glutathione S-transferase P1 (GSTP1) enzymes and polymorphisms, which are found in phase II detoxification reactions in the development of cervical cancer.

Methods

This study was conducted with 46 patients diagnosed with cervical cancer and 52 people with no cancer history. Multiplex PCR methods were used to evaluate the GSTM1 and GSTT1 gene polymorphism. However, the GSTP1 (Ile105Val) gene polymorphism was studied using a PCR-RFLP method. The patient and control groups were compared using a chi-square test with p<0.05.

Results

In the patient group, statistical significance was determined for gravidity (p=0.03), parity (p=0.01), and the number of living children (p=0.01) compared to the control group. The gene frequency of GSTM1, GSTT1, and GSTP1 polymorphisms was evaluated. We observed that GSTM1 and GSTT1 null genotype frequencies were 54.3% and 32.6% respectively, while GSTP1 (Ile/Val), (Ile/Ile), (Val/Val) genotype frequencies were 52%, 44%, and 4%, respectively, in the cervical cancer patients. No statistical variation was determined between the control and patient groups in terms of GSTM1, GSTT1, and GSTP1 polymorphisms (p>0.05).

Conclusion

Our results demonstrate that GSTT1, GSTM1, and GSTP1 polymorphisms are not associated with cervical cancer in Turkish patients.     

Association between the HER2 Ile655Val polymorphism and response to trastuzumab in women with operable primary breast cancer

BackgroundHuman epidermal growth factor receptor 2 (HER2) Ile655Val polymorphism may affect the efficacy of trastuzumab treatment of breast cancer.Patients and methodsHER2 Ile655Val polymorphism was determined in 4167 patients with primary breast cancer using a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) assay. We investigated the associations between the HER2 Ile655Val polymorphism and clinical outcomes in women with HER2-negative breast cancer and with HER2-positive breast cancer who received trastuzumab or who did not.ResultsAt a median follow-up of 44 months, HER2 Ile655Val polymorphism was not significantly associated with survival either in the entire study population of 4167 patients or in 2976 HER2-negative breast cancer patients. Among 816 HER2-positive patients who received adjuvant chemotherapy and/or endocrine therapy without trastuzumab treatment, patients with the Val/Ile or the Val/Val genotype had a significantly worse disease-free survival (DFS) and distant DFS (DDFS) than those with the Ile/Ile genotype (DFS, adjusted hazard ratio [HR] 1.5; 95% confidence interval [CI] 1.0–2.3; P = 0.037; DDFS, adjusted HR 1.9; 95% CI 1.2–2.9 P = 0.005). In contrast, among 212 HER2-positive patients who received chemotherapy in combination with trastuzumab treatment, patients with the Val/Ile or the Val/Val genotype had a significantly better DFS and DDFS than those with the Ile/Ile genotype (5-year DFS, 100% versus 83%; P = 0.008; 5-year DDFS, 100% versus 89%; P = 0.031).ConclusionsHER2 Ile655Val polymorphism affects the function of HER2 gene only restricted in HER2-positive breast cancers. HER2-positive breast cancer patients with the Val variant have an aggressive phenotype, but are sensitive to trastuzumab treatment.     

Association of Tobacco Use,Alcohol Consumption and HER2 Polymorphisms With Response to Trastuzumab in HER2-Positive Breast Cancer Patients

Purpose

Although the administration of trastuzumab has improved the survival of human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients, resistance remains a major clinical obstacle. We retrospectively evaluated the association of HER2 polymorphisms, tobacco use and alcohol consumption with disease-free survival (DFS) in HER2-positive breast cancer patients.

<Emphasis Type="Italic">FGFR4</Emphasis> Gly<Superscript>388</Superscript>Arg polymorphism contributes to prostate cancer development and progression: A meta-analysis of 2618 cases and 2305 controls

Background  

Fibroblast growth factor receptor 4 (FGFR4) displays multiple biological activities, including mitogenic and angiogenic activity, and plays important roles in the etiology and progression of prostate cancer. Gly³⁸⁸Arg polymorphism in FGFR4 gene has been reported to be involved in prostate cancer incidence and aggressiveness in several studies. To derive a more precise estimation of the relationship, a meta-analysis was performed.     

Dietary fat increases solid tumor growth and metastasis of 4T1 murine mammary carcinoma cells and mortality in obesity-resistant BALB/c mice

Introduction  

High-fat diets (HFDs) are known to cause obesity and are associated with breast cancer progression and metastasis. Because obesity is associated with breast cancer progression, it is important to determine whether dietary fat per se stimulates breast cancer progression in the absence of obesity. This study investigated whether an HFD increases breast cancer growth and metastasis, as well as mortality, in obesity-resistant BALB/c mice.     

CYP1A1 MspI and exon7 gene polymorphisms and lung cancer risk: An updated meta-analysis and review

Background

Many studies have examined the association between the CYP1A1 MspI and exon 7 gene polymorphisms and lung cancer risk in various populations, but their results have been inconsistent.

Methods

To assess this relationship more precisely, a meta-analysis and review were performed. The PubMed, Embase, Web of Science, and CNKI database was searched for case-control studies published up to June 2010. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated.

Results

Ultimately, 64 studies, comprising 18,397 subjects from 49 case-control studies of the MspI genotype and 18,518 patients from 40 case-control studies of the exon 7 genotype, were included. A significantly elevated lung cancer risk was associated with 2 MspI genotype variants (for type C vs Type A: OR = 1.26, 95% CI = 1.12-1.42; for types B and C combined vs Type A: OR = 1.20, 95% CI = 1.13-1.28) in overall population. In the stratified analysis, a significant association was found in Asians, Caucasians, lung SCC, lung AC and Male population, not in mixed population, lung SCLC and Female population. However, inconsistent results were observed for CYP1A1 exon7 in our meta-analysis, two variants of the exon 7 polymorphism were associated with a significantly higher risk for lung cancer (for Val/Val vs Ile/Ile: OR = 1.24, 95% CI = 1.09-1.42; for (Ile/Val +Val/Val) vs Ile/Ile: OR = 1.15, 95% CI = 1.07-1.24) in overall population. In the stratified analysis, a significant assocation was found in Asians, Caucasians, lung SCC and Female population, not in mixed population, lung AD, lung SCLC and Male population. Additionally, a significant association was found in smoker population and not found in non-smoker populations for CYP1A1 MspI and exon7 gene.

Conclusions

This meta-analysis suggests that the MspI and exon 7 polymorphisms of CYP1A1 correlate with increased lung cancer susceptibility and there is an interaction between two genotypes of CYP1A1 polymorphism and smoking, but these associations vary in different ethnic populations, histological types of lung caner and gender of case and control population.     

Association of Aurora-A (STK15) kinase polymorphisms with clinical outcome of esophageal cancer treated with preoperative chemoradiation

BACKGROUND:

Aurora‐A/STK15 is a serine/threonine kinase critical for regulated chromosome segregation and cytokinesis. We investigated the association between 2 nonsynonymous single nucleotide polymorphisms in the coding region of STK15, T91A (Phe31Ile) and G169A (Val57Ile), and clinical outcome of esophageal cancer treated with preoperative chemoradiation.

METHODS:

Genotypes at Phe31Ile and Val57Ile were assessed from peripheral blood lymphocytes of 190 esophageal cancer patients and were correlated to response to treatment, recurrence rate, risk of death, disease‐free survival (DFS) and median survival time (MTS).

RESULTS:

All patients had resectable esophageal or gastroesophageal junction cancer and received preoperative chemoradiation followed by esophagectomy. The heterozygous variant Phe31/Ile variant was significantly associated with tumor recurrence (odds ratio [OR] = 4.39; 95% confidence interval [CI], 2.12‐8.94; P < .001), shorter DFS (P = .0001), and shorter MTS (P = .012). For patients receiving cisplatin‐based therapy, only the variant Phe31/Ile had an adverse effect on response (OR = 2.8; 95% CI, 1.01‐5.17; P = .048) and MTS (P = .026). The variant 91A‐169G haplotype carried a significant risk for lack of complete response (OR = 2.54; 95% CI, 1.15‐5.54) and higher rate of recurrence (OR = 2.73; 95%CI, 1.00‐7.29). The presence of at least 1 variant allele at each locus further increased the risk of recurrence (adjusted OR = 6.21; 95% CI, 2.28‐17.11; P = <.001), and was associated significantly shorter DFS (P = .003).

CONCLUSIONS:

Our study shows that functional SNPs in the STK15 gene are associated with higher rate of recurrence, higher likelihood of chemoratiotherapy‐resistance, shorter DFS, and shorter MTS. Confirmation of our data and understanding the mechanisms through which STK15 functional SNPs mediate resistance to chemoradiotherapy are warranted. Cancer 2012. © 2011 American Cancer Society.     

Cytochrome P450 1A1 (CYP1A1) polymorphism and susceptibility to esophageal cancer: an updated meta-analysis of 27 studies

Cytochrome P450 1A1 (CYP1A1) polymorphisms are known to play a crucial role in the development and metastasis of malignant diseases including esophageal cancer. However, the results of previous studies investigating the association between CYP1A1 polymorphisms and esophageal cancer risk have been inconsistent. This meta-analysis of 27 eligible studies, encompassing 4,215 esophageal cancer cases and 6,339 control subjects, pooled the odds ratios (ORs) with corresponding 95 % confidence intervals (95 % CI) to assess this association. The effects of ethnicity (Caucasian and Asian) and histopathology type (esophageal squamous cell carcinoma and esophageal adenocarcinoma) were considered in subgroup analyses. A significant association was observed between the CYP1A1 Ile/Val gene polymorphism and esophageal cancer in all of the genetic models (Ile/Val vs. Ile/Ile, OR?=?1.41, 95 % CI?=?1.25–1.58; Val/Val vs. Ile/Ile, OR?=?1.94, 95 % CI?=?1.34–2.82; Ile/Val?+?Val/Val vs. Ile/Ile, OR?=?1.49, 95 % CI?=?1.33–1.66). The subgroup analysis based on ethnicity showed that the association between the CYP1A1 Ile/Val polymorphism and esophageal cancer existed in Asian and Caucasian populations. However, no association was observed between the CYP1A1 MspI polymorphism and esophageal cancer in either subgroup or in the overall population. These results suggested that the CYP1A1 Ile/Val polymorphism was associated with an increased risk of esophageal cancer, whereas the CYP1A1 MspI polymorphism may not have increased susceptibility to esophageal cancer. Further studies are required to confirm these findings.     

四川人群中CYP1A1基因Ile-Val和Msp1位点多态性与肺癌易感性的研究

目的　探讨细胞色素P45 0 (CYP1A1)基因异亮氨酸 (Ile) 缬氨酸 (Val)位点和Msp1位点多态性和肺癌易感性的相关关系。方法　以病例对照的研究方法 ,采用PCR RFLP和ASA PCR技术检测 82例原发性肺癌和 91例对照的CYP1A1基因Ile Val位点和Msp1位点多态性。 结果　Ile Val三种多态基因型在肺癌组和对照组分布差异有显著性 (P <0 .0 5 ) ,Ile/Val、Val/Val基因型在肺癌组的分布频率明显高于对照组 ;logistic回归分析结果显示Ile/Val、Val/Val基因型患肺癌的危险分别是Ile/Ile基因型的 1.969倍和3 .15 0倍 ;当按吸烟分层后 (将Ile/Val、Val/Val基因型合并分析 ) ,吸烟组中Ile/Val、Val/Val合并基因型患肺癌的危险是Ile/Ile基因型的 3 .0 5 9倍 ,而在不吸烟组其OR为 1.687;Msp1位点多态性在肺癌组和对照组差异无统计学意义。结论　CYP1A1第 7外显子的Ile/Val、Val/Val基因型与肺癌的易感性有关 ,可望作为肺癌易感人群筛选的重要指标 ;尚不能认为Msp1多态性与肺癌的易感性有关     

Glutathione S-transferase P1 Ile105Val polymorphism and breast cancer risk: a meta-analysis involving 34,658 subjects

Glutathione S-transferase P1 (GSTP1) is involved in a wide range of detoxifying reactions. Any alteration in the structure, function, or expression of GSTP1 gene may alter the ability of a cell to inactivate carcinogens or mutagens, and thus modify an individual’s risk to cancer. Previous epidemiological studies on the potential association between GSTP1 Ile105Val polymorphism and breast cancer risk have produced inconsistent results. In order to drive a more precise estimation of this association, we performed a meta-analysis of 30 published case–control studies including 15,901 cases and 18,757 controls. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. The results of this meta-analysis showed that GSTP1 Ile105Val polymorphism was not associated with breast cancer susceptibility in overall population. However, in subgroup analysis by ethnicity, we found a significant association among Asian population (for Val/Val vs. Ile/Ile: OR 1.27, 95% CI 1.02–1.83; for the recessive model Val/Val vs. Ile/Ile + Ile/Val: OR 1.42, 95% CI 1.20–1.69). When stratified by study design, significantly elevated susceptibility to breast cancer was found among hospital-based studies (for Val/Val vs. Ile/Ile: OR 1.38, 95% CI 1.16–1.63; for recessive model Val/Val vs. Ile/Val + Ile/Ile: OR 1.31, 95% CI 1.12–1.55; for dominant model: Val/Val + Ile/Val vs. Ile/Ile: OR 1.10, 95% CI 1.02–1.19). In conclusion, our meta-analysis suggests that GSTP1 Ile105Val polymorphism may increase susceptibility to breast cancer in Asian population.     

Lack of association between HER2 codon 655 polymorphism and breast cancer susceptibility: meta-analysis of 22 studies involving 19,341 subjects

Epidemiological studies have investigated the association between HER2 codon 655 polymorphism and breast cancer susceptibility. However, the results are still inconclusive. To obtain a more precise estimation of the relationship, this meta-analysis was performed. A total of 22 studies including 9,209 cases and 10,132 controls were collected. The strength of association between HER2 codon 655 polymorphism and breast cancer susceptibility was assessed by calculating crude ORs with 95% CIs. When all the 22 studies were pooled into the meta-analysis, there was no evidence for significant association between HER2 codon 655 polymorphism and breast cancer susceptibility (for Val/Ile vs. Ile/Ile: OR = 1.069, 95% CI = 0.976–1.172; for Val/Val vs. Ile/Ile: OR = 1.191, 95% CI = 0.922–1.538; for dominant model: OR = 1.093, 95% CI = 0.991–1.206; for recessive model: OR = 1.141, 95% CI = 0.902–1.444). In the subgroup analysis by the source of controls and ethnicity, no significant increased risk was found in all genetic models. However, the current results indicated the modest association between the HER2 Ile655Val polymorphism and Asian population (Val/Ile vs. Ile/Ile: OR = 1.207, CI = 1.006–1.450). In summary, the meta-analysis suggests that HER2 codon 655 polymorphism is not associated with the increased breast cancer risk.     

No association between HER-2 gene polymorphism at codon 655 and a risk of bladder cancer

The amplification and overexpression of the human epidermal growth factor receptor 2 gene HER-2 (also known as c-erb-B2 or neu) have been shown to be associated with bladder cancer and its progression. Recent studies indicated an association between the Ile to Val polymorphism at codon 655 of HER-2 and susceptibility to breast cancer. To investigate the correlation between the Ile/Val polymorphism and the susceptibility and progression of bladder cancer, we analyzed the polymorphism in 232 patients with transitional cell carcinoma of the bladder and 408 normal controls. The frequencies of the Ile/Ile, Ile/Val and Val/Val genotype were 75.9%, 21.6% and 2.6%, respectively, in patients with bladder cancer and 75.7%, 23.0% and 1.2%, respectively, in controls. Statistical analyses of the genotype prevalence showed no significant difference between bladder cancer patients and normal controls (p = 0.419). Moreover, no significant differences in the genotype prevalence were observed when the patients were stratified according to the tumor grade, stage and smoking habits. When the Ile/Ile genotype was compared to the Ile/Val and Val/Val genotypes, a significant difference was found only between the patients with tumor stage Ta and those with T1-4 (age, gender and smoking habits-adjusted odds ratio = 2.13, 95% confidence interval = 1.09-4.15, p = 0.027). When the Ile/Ile + Ile/Val genotypes compared to the Val/Val genotype, no significant findings were observed. These results suggested that the HER-2 polymorphism at codon 655 is unlikely to be associated with the onset of bladder cancer. Furthermore, the findings suggest no association between this polymorphism and the disease progression in bladder cancer, although the possibility remains that the Ile/Ile genotype may be related to an increased risk of disease progression.     

MRP2 and GSTP1 polymorphisms and chemotherapy response in advanced non-small cell lung cancer

Purpose

The level of drug metabolism and drug transport is correlated with the sensitivity of cancer cells towards platinum-based chemotherapy. We hypothesize that genetic polymorphisms in metabolising enzymes gene GSTP1 (glutathione S-transferase P1), and MRP2 (multidrug resistance-associated protein 2) (ABCC2), which result in inter-individual differences in metabolism and drug disposition, may predict clinical response to platinum agents in advanced non-small cell lung cancer (NSCLC) patients.

Methods

Totally 113 patients with advanced NSCLC were routinely treated with platinum-based chemotherapy, and clinical response was evaluated after four cycles. MRP2 C-24T (?24C>T), MRP2 Val417Ile (1249G>A), MRP2 Ile1324Ile (3972C>T), and GSTP1 Ile105Val (342A>G) genotype were determined by gene-chip method (a 3-D (three dimensions) polyacrylamide gel-based DNA microarray method) using DNA samples isolated from peripheral blood collected before treatment. Pearson Chi-square test and Fisher’s exact test were performed to measure the differences of the chemotherapeutic efficacy among variant genotype. The odds ratios and 95% confidence intervals were computed by logistic regression.

Results

The C→T change of MRP2 C-24T and the A→G change of GSTP1 Ile105Val polymorphism significantly increased platinum-based chemotherapy response.

Conclusion

The polymorphic status of MRP2 C-24T and GSTP1 Ile105Val might be the predictive markers for the treatment response of advanced NSCLC patients. The DNA microarray-based method is accurate, high throughput and inexpensive, suitable for single-nucleotide polymorphism genotyping in a large number of individuals.     

A single nucleotide polymorphism in the transmembrane domain coding region of HER-2 is associated with development and malignant phenotype of gastric cancer

Alterations of the HER-2 (erbB-2/neu) proto-oncogene have been associated with carcinogenesis and poor prognosis of certain cancers. A single nucleotide polymorphism (Ile/Val, A/G) in the transmembrane domain was reported to be associated with a risk of breast cancer. In our study, we examined the association between the HER-2 polymorphism and gastric carcinoma. The Ile/Ile, Ile/Val and Val/Val genotypes were found in 146 (68.9%), 56 (26.4%) and 10 (4.7%) of 212 gastric cancer patients and in 234 (81.5%), 48 (16.7%) and 5 (1.8%) of 287 control subjects, respectively. The Ile/Val or Val/Val genotype was significantly more frequent in patients than in controls (p = 0.005 and 0.033, respectively). The OR of Val/Val genotype then revealed a significantly enhanced risk of 3.25 (95% CI 1.09-9.70) compared to Ile/Ile genotype; heterozygous Ile/Val genotype showed an intermediate risk of 1.97 (1.27-3.06). In patients, carcinomas of advanced stage were significantly more frequent in patients with Ile/Val or Val/Val genotype than those with Ile/Ile genotype (p < 0.001). The logistic regression analysis for tumor invasion, lymph node metastasis and distant metastasis revealed that lymph node metastasis was most closely associated with the HER-2 genotype. These results suggest that this nucleotide polymorphism in the transmembrane domain-coding region of HER-2 could be associated with development of gastric carcinoma and may serve as a predictor of risk for a malignant phenotype of gastric cancer. The association of HER-2 genotype with clinicopathologic characteristics of gastric cancer was also suggested, which has to be confirmed with a larger sample size.     

HER2 codon 655 polymorphism and risk of breast cancer in African Americans and whites

Background. Several recent epidemiologic studies examined the association between breast cancer risk and an inherited, single-nucleotide polymorphism in the HER2 gene, codon 655 G to A, which leads to an amino acid substitution of Ile to Val. Results of previous studies have been mixed, with most studies showing no association but some suggesting an association in younger women or women with a family history of breast cancer. Methods. We conducted an association study of HER2 codon 655 genotype and breast cancer within the Carolina Breast Cancer study, a population-based, case-control study of in situ and invasive breast cancer in African American and white women in North Carolina. A total of 2015 cases and 1808 controls were genotyped. Results. We observed no overall association between HER2 genotype and breast cancer. However, a modest positive association (OR = 2.3, 95% CI 1.0–5.3) was observed for Val/Val + Ile/Val versus Ile/Ile genotypes in women age 45 or younger with a family history of breast cancer. Val/Val homozygotes were more common among cases with in situ versus invasive disease (P = 0.002). Breast tumors from women with Val/Val genotype were more likely to exhibit HER2 overexpression, but the results were not statistically significant (P = 0.17). Conclusions. The HER2 codon 655 polymorphism may be one of many low-penetrant genes that make a minor contribution to breast cancer, particularly in subgroups of women. Additional large studies, as well as data pooling, will be needed to estimate the contribution of such genes to breast cancer risk.     

Manganese superoxide dismutase Ala-9Val polymorphism and risk of breast cancer in a population-based case–control study of African Americans and whites

Introduction  

A polymorphism in the manganese superoxide dismutase (MnSOD) gene, Ala-9Val, has been examined in association with breast cancer risk in several epidemiologic studies. Results suggest that the Ala allele increases the risk of breast cancer and modifies the effects of environmental exposures that produce oxidative damage to DNA.     

Glutathione-S-transferase pi (GSTP1) codon 105 polymorphism is not associated with oxaliplatin efficacy or toxicity in advanced colorectal cancer patients

PurposeOxaliplatin is detoxified by conjugation to glutathione via the enzyme Glutathione-S-transferase pi (GSTP1). The aim of this study is to investigate the association of GSTP1 Ile105Val genetic polymorphism with oxaliplatin efficacy and toxicity in advanced colorectal cancer (ACC) patients.Experimental designA total of 91 ACC patients received capecitabine and oxaliplatin (CAPOX) as a part of a multicentre phase-III study of the Dutch Colorectal Cancer Group. Tumour response was evaluated according to RECIST, toxicity was graded using CTC, and GSTP1 Ile105Val was determined by pyrosequencing.ResultsOverall survival after CAPOX was similar for patients with the Ile/Ile (11.5 mo), Ile/Val (11.6 mo) and Val/Val (12.6 mo) genotypes (p = 0.602). Likewise, there were no statistically significant differences in progression-free survival (p = 0.252). Overall grades 3–4 toxicity was not related to genotype (p = 0.313). There were no differences in any grade or grades 3–4 neurotoxicity amongst the patients who received ?500 mg/m² of oxaliplatin (p-values of 0.376 and 0.772, respectively).ConclusionsThe results of this study indicate that the GSTP1 genotype is not predictive for progression-free survival or overall survival in ACC patients treated with CAPOX. Moreover, overall neurotoxicity and neurotoxicity in patients receiving ?500 mg/m² of oxaliplatin was not associated with GSTP1 genotype.