APE1 polymorphisms are associated with colorectal cancer susceptibility in Chinese Hans

AIM: To study the association between four base excision repair gene polymorphisms and colorectal cancer risk in a Chinese population.METHODS: Two hundred forty-seven colorectal cancer (CRC) patients and three hundred cancer-free controls were enrolled in this study. Four polymorphisms (OGG1 Ser326Cys, APE1 Asp148Glu, -141T/G in the promoter region, and XRCC1 Arg399Gln) in components of the base excision repair pathway were determined in patient blood samples using polymerase chain reaction with confronting two-pair primers. The baseline information included age, gender, family history of cancer, and three behavioral factors [smoking status, alcohol consumption, and body mass index (BMI)]. χ² tests were used to assess the Hardy-Weinberg equilibrium, the distributions of baseline characteristics, and the four gene polymorphisms between the cases and controls. Multivariate logistic regression analyses were conducted to analyze the correlations between the four polymorphisms and CRC risk, adjusted by the baseline characteristics. Likelihood ratio tests were performed to analyze the gene-behavior interactions of smoking status, alcohol consumption, and BMI on polymorphisms and CRC susceptibility.RESULTS: The APE1 148 Glu/Glu genotype was significantly associated with an increased risk of colorectal cancer (OR = 2.411, 95%CI: 1.497-3.886, P < 0.001 relative to Asp/Asp genotype). There were no associations between OGG1, XRCC1, or APE1 promoter polymorphisms and CRC risk. A multivariate analysis including three behavioral factors showed that the APE1 148 Glu/Glu genotype was associated with an increased risk for CRC among both smokers and non-smokers, non-drinkers and individuals with a BMI ≥ 25 kg/m² (ORs = 2.356, 3.299, 2.654, and 2.581, respectively). The XRCC1 399 Arg/Gln genotype was associated with a decreased risk of CRC among smokers and drinkers (OR = 0.289, 95%CI: 0.152-0.548, P < 0.001, and OR = 0.327, 95%CI: 0.158-0.673, P < 0.05, respectively). The APE1 promoter polymorphism -141 T/G genotype was associated with a reduced risk of colorectal cancer among subjects with a BMI < 25 kg/m² (OR = 0.214, 95%CI: 0.069-0.660, P < 0.05 relative to T/T genotype). There were significant gene-behavior interactions between smoking status and XRCC1 Arg399Gln, as well as BMI and APE1 -141T/G polymorphism (all P < 0.05).CONCLUSION: APE1 Asp148Glu is associated with increased CRC risk and smoking alters the association between XRCC1 Arg399Gln and CRC risk in the Chinese Han population.     

UGT1A1 predicts outcome in colorectal cancer treated with irinotecan and fluorouracil

AIM: To evaluate effects of UDP-glucuronosyltransferase1A1 (UGT1A1) and thymidylate synthetase (TS) gene polymorphisms on irinotecan in metastatic colorectal cancer (mCRC).METHODS: Two irinotecan- and fluorouracil-based regimens, FOLFIRI and IFL, were selected as second-line therapy for 138 Chinese mCRC patients. Genomic DNA was extracted from peripheral blood samples before treatment. UGT1A1 and TS gene polymorphisms were determined by direct sequencing and restriction fragment length polymorphism, respectively. Gene polymorphisms of UGT1A1*28, UGT1A1*6 and promoter enhancer region of TS were analyzed. The relationship between genetic polymorphisms and clinical outcome, that is, response, toxicity and survival were assessed. Pharmacokinetic analyses were performed in a subgroup patients based on different UGT1A1 genotypes. Plasma concentration of irinotecan and its active metabolite SN-38 and inactive metabolite SN-38G were determined by high performance liquid chromatography. Differences in irinotecan and its metabolites between UGT1A1 gene variants were compared.RESULTS: One hundred and eight patients received the FOLFIRI regimen, 29 the IFL regimen, and one irinotecan monotherapy. One hundred and thirty patients were eligible for toxicity and 111 for efficacy evaluation. One hundred and thirty-six patients were tested for UGT1A1*28 and *6 genotypes and 125 for promoter enhancer region of TS. Patients showed a higher frequency of wild-type UGT1A1*28 (TA6/6) compared with a Caucasian population (69.9% vs 45.2%). No significant difference was found between response rates and UGT1A1 genotype, although wild-type showed lower response rates compared with other variants (17.9% vs 24.2% for UGT1A1*28, 15.7% vs 26.8% for UGT1A1*6). When TS was considered, the subgroup with homozygous UGT1A1*28 (TA7/7) and non-3RG genotypes showed the highest response rate (33.3%), while wild-type UGT1A1*28 (TA6/6) with non-3RG only had a 13.6% response rate, but no significant difference was found. Logistic regression showed treatment duration was closely linked to clinical response. In toxicity comparison, UGT1A1*28 TA6/6 was associated with lower incidence of grade 2-4 diarrhea (27.8% vs 100%), and significantly reduced the risk of grade 4 neutropenia compared with TA7/7 (7.8% vs 37.5%). Wild-type UGT1A1*6 (G/G) tended to have a lower incidence of grade 3/4 diarrhea vs homozygous mutant (A/A) genotype (13.0% vs 40.0%). Taking UGT1A1 and TS genotypes together, lower incidence of grade 2-4 diarrhea was found in patients with non-3RG TS genotypes, when TA6/6 was compared with TA7/7 (35.3% vs 100.0%). No significant association with time to progression (TTP) and overall survival (OS) was observed with either UGT1A1 or TS gene polymorphisms, although slightly longer TTP and OS were found with UGT1A1*28 (TA6/6). Irinotecan PK was investigated in 34 patients, which showed high area under concentration curve (AUC) of irinotecan and SN-38, but low AUC ratio (SN-38G / SN-38) in those patients with UGT1A1*28 TA7/7.CONCLUSION: A distinct distribution pattern of UGT1A1 genotypes in Chinese patients might contribute to relatively low toxicity associated with irinotecan and 5-fluorouracil in mCRC patients.     

Interactions between CYP2C9 and UGT1A6 polymorphisms and nonsteroidal anti-inflammatory drugs in colorectal cancer prevention.

BACKGROUND AND AIMS: Variant genotypes of uridine diphosphate glucuronsyltransferase isoenzyme 1A6 (UGT1A6) associated with decreased metabolic activity have been associated with an enhanced protective effect of aspirin on the development of colorectal adenomas. However, interactions between UGT1A6 variants or variants of another enzyme that metabolizes nonsteroidal anti-inflammatory drugs (NSAIDs), cytochrome P4502C9 (CYP2C9), and NSAIDs in the prevention of colorectal cancer have not been studied extensively. METHODS: UGT1A6 and CYP2C9 genotypes were determined in 2295 individuals with colorectal cancer and 2903 controls. Interactions between these genotypes, aspirin or ibuprofen use, and colorectal cancer risk were determined. RESULTS: Variant CYP2C9 genotypes enhanced the protective effect of ibuprofen on the prevention of colorectal cancer, and a dose-response relationship with respect to increasing numbers of variant alleles was seen (P interaction = .02). CYP2C9 variants were more effective in individuals with wild-type rather than variant UGT1A6 (P interaction < .007). Variant CYP2C9 genotypes showed no interaction with aspirin usage, and variant UGT1A6 genotypes showed no interaction with either NSAID with respect to colorectal cancer protection. CONCLUSIONS: In this study, the major effect seen was an enhancement by slower-metabolizing CYP2C9 variants of the chemopreventive activity of ibuprofen against colorectal cancer.     

Severe irinotecan-induced toxicity in a patient with UGT1A1*28 and UGT1A1*6 polymorphisms

Many studies have demonstrated the impact of UGT1A1 on toxicity of irinotecan. In particular, patients bear-ing UGT1A1*28 (TA 7/7) have a higher risk of severe neutropenia and diarrhea. Based on this, prescribers of irinotecan are advised that patients with UGT1A1*28 (TA 7/7) should start with a reduced dose of irinotecan, although a particular dose is not specified. Research in Asian countries has shown a lower incidence of UG-T1A1*28 (TA 7/7), while UGT1A1*6 (A/A) is more often found and is associated with severe irinotecan-related neutropenia. We report here a case of a metastatic colorectal cancer patient who is heterozygous for the UGT1A1*28 polymorphism (TA 6/7) as well as the UG-T1A1*6 polymorphism (G/A). The patient was treated with FOLFIRI for 9 cycles and underwent two irinote-can dose reductions according to pharmacokinetic data regarding exposure to the active metabolite, SN-38. Simultaneous heterozygous UGT1A1*28 and UGT1A1*6 polymorphisms may produce higher exposure to SN-38 and a higher risk of adverse effects related to irinote-can. Additional studies will be necessary to determine the optimal starting dose of irinotecan for patients with both UGT1A1*28 and UGT1A1*6 polymorphisms.     

X线损伤交叉互补基因1多态性与结直肠癌易感性研究

目的 探讨DNA修复酶X线损伤交叉互补基因1(XRCC1 )外显子三个位点的基因多态性(Arg194Trp 、Arg280His、Arg399Gln)与结直肠癌(CRC)发病风险的关系.方法 以聚合酶链反应和限制性片段长度多态性(PCR-RFLP)分析方法,采用病例-对照研究,对250例CRC患者(病例组,其中结肠癌128例,直肠癌122例)和213名健康人(对照组)的XRCC1基因三个位点的多态性进行了检测,采用SPSS 11.0软件包统计分析各位点的基因型分布和等位基因频率.结果 XRCC1基因194和399二个位点的各基因型频率在两组间分布差异均无统计学意义(P值均>0.05),但病例组XRCC1基因280 Arg/His基因型频率较对照组显著增高(校正后OR=1.66,95%CI:1.01～2.73,P=0.047).在直肠癌患者组中,280Arg/His基因型频率较对照组显著增高(OR=1.82,95%CI:1.02～3.27),携等位基因280His(Arg280His +His280His)的CRC患者的频率显著高于其在对照组中的频率(校正后OR=1.85,95%CI:1.06～3.22),而在结肠癌患者中风险系数相对较低且差异无统计学意义(校正后OR=1.31,95%CI:0.74～2.35).结论 XRCC1 Arg194Trp和 Arg399Gln基因多态性与结肠癌易感性无关,但280Arg/His基因型能增加CRC易感性,等位基因280His是直肠癌风险因素.

Abstract：

Objective To investigate the correlation between three gene locus polymorphisms of X-ray repair cross-complementary protein 1 (XRCC1) exon (Arg194Trp, Arg280His and Arg399Gln) and the risk of colorectal cancer (CRC). Methods A case-control study was performed in 250 CRC patients (case group, 128 colon cancer patients and 122 rectal cancer patients) and 213 healthy individuals (control group). The three gene locus polymorphism of XRCC1 was tested by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) method. The genotype distribution and allele frequency of each locus was analyzed with SPSS 10.0 software. Results There was no significant difference in allele frequency of XRCC1 at 194 and 399 loci (P > 0.05). However, the 280 Arg/His allele frequency of XRCC1 was higher in case group than that in control group (OR=1.66,95%CI:1.01~2.73,P=0.047). The 280Arg/His allele frequency was higher in rectal cancer group than that in control group (OR =1.82,95%CI:1.02~3.27). The frequency of 280His allele (Arg280His and His280His) was higher in case group than that in control group (OR=1.85,95%CI:1.06~3.22). However, it was a relative low risk factor of colon cancer and there was no significant difference between colon cancer group and control group (OR=1.85, 95%CI:1.06~3.22). Conclusions There was no correlation between XRCC1 Arg194Trp and Arg399Gln polymorpohisms and the risk of CRC. However, 280Arg/His genotype may increase the risk of CRC, and 280His allele is a risk factor of rectal cancer.     

Lack of association between UGT1A7, UGT1A9, ARP, SPINK1 and CFTR gene polymorphisms and pancreatic cancer in Italian patients

INTRODUCTION Pancreatic cancer (PC) is still a major cause of morbidity and mortality worldwide. Despite extensive research, its etiology remains elusive. Recent data suggest that both genetic and environmental factors play a role in the development and p…     

胸苷酸合成酶基因多态性与结直肠癌易感性的关系

目的研究胸苷酸合成酶（thymidylate synthase．TS）基因5＇-非翻译区（untranslated region，UTR）、3＇-UTR多态性及其与饮酒之间的联合作用和结直肠癌（colorectal cancer，CRC）易感性的关系。方法采用病例对照研究（140例病例和343例对照）设计，通过非条件Logistic回归模型和似然比检验分析TS上述多态性及其与饮酒之间的联合作用和CRC易感性之间的关系。结果单独的TS基因多态性与CRC之间无明显联系。两多态性之间联合作用的P值为0．05。无饮酒史者中，＋6bp等位基因是CRC的保护因素（OR=0．57．95％CI．0．32～0．99）．有饮酒史者中，＋6bp等位基因携带者患CRC的风险增加（OR=1．88，95％CI．0．80～4．41），并且随着饮酒年限的延长，OR值逐渐升高。似然比检验提示两者之间存在交互作用（P=0．01）。结论尚不能认为TS基因5LUTR和3LUTR多态性是CRC风险的独立预测因子，两多态性之间、3＇-UTR多态性与饮酒之间存在交互作用，共同改变个体罹患结直肠癌的风险。     

APE1 D148E、PARP1 V762A、XRCC1 R399Q的多态性与结直肠癌的易患性

目的:探讨APE1 D148E、PARP1 V762A及XRCC1 R399Q的碱基切除修复基因单核苷酸多态位点对结直肠癌发病风险的修饰作用.方法:选取158例健康对照与123例原发性结直肠癌患者,提取外周血基因组DNA,用基质辅助激光解吸电离飞行时间(MALDI-TOF)质谱技术对SNP位点进行基因分型,在各混杂因素配比下,采用X2检验比较病例组与对照组中各SNP的基因型分布差异以及多SNP的联合基因型分布差异,从而分析他们对结直肠癌风险的修饰程度OR值.结果:3个SNP在本研究中均符合Hardy-Weinberg平衡,其中只有XRCC1 R399Q的GA/AA变异(V)型与结直肠癌发病有正相关性,OR值为1.633(95%CI:1.011-2.640.P=0.045);而APE1 D148E、PARP1 V762A的SNP变异单独对结直肠癌风险未见明显影响(P>0.05).联合基因型在两组比较显示,携带APE1(V)-PARP1(W)-XRCC1(V)者,结直肠癌发病风险是其他联合基因型携带者的2.604倍(95%CI:1.066-6.361,P=0.031);而其他联合基因型对结直肠癌风险的修饰作用则不明显.结论:XRCC1 rs25487的GA/AA变异型是结直肠癌的危险因素;BER和SNP存在交互作用;携带联合基因型APE1(V)-PARP1(W)-XRCC1(V)者患结直肠癌的风险可能较高.     

Link between colorectal cancer and polymorphisms in the uridine-diphosphoglucuronosyltransferase 1A7 and 1A1 genes

AIM: To investigate the relationship between single nucleotide polymorphisms in the uridine-diphosphoglucurono-syltransferase (UGT) UGT1A7 and UGT1A1 genes and patients suffering from colorectal cancer (CRC). METHODS: A case-control study was designed in order to investigate the genotypes of the UGT1A7 and UGT1A1 genes, which were identified by the polymerase chain reaction-restriction fragment length polymorphism (RFLP) method, for 268 CRC patients and 441 healthy controls. RESULTS: The results of simple logistical regressions revealed odds ratios (ORs) of 1.97 (P<0.001),1.91 (P<0.001),and 2.03 (P<0.001) for patients who carried the UGT1A7*1/*3 genotype,UGT1A7*3 allele,and variant-211 UGT1A1 allele.The interaction of UGT1A7*3 allele and variant-211 UGT1A1 allele produced an additive effect on the risk for the development of CRC [observed OR (2.34) greater than expected OR (1.59)]. For the 268 patients, the results of simple logistical regressions indicated that the OR of developing metastases was 4.90 (P<0.001) and 4.89 (P<0.001) for the individuals possessing UGT1A7*3 allele and variant-211 UGT1A1 allele, respectively. The results of multivariate logistical regressions confirmed these findings (OR = 2.51, P= 0.01; and OR=2.71,P=0.01,respectively).The interaction of these two variants resulted in an additive effect on the risk for metastases amongst patients [observed OR (6.83) greater than expected OR (4.56)]. CONCLUSION: In conclusion, carriage of the UGT1A7*3 allele, as well as variant-211 UGT1A1 allele represents a risk factor for the development of, and a determinant for, metastases associated with CRC patients.     

A meta-analysis on XRCC1 and XRCC3 polymorphisms and colorectal cancer risk

Purpose  

Studies on polymorphism of X-ray repair cross-complementing group 1 (XRCC1), group 3 (XRCC3), and colorectal cancer risk are inconclusive. The purpose of this study is to evaluate the role of XRCC1 R399Q, R194W, and XRCC3 T241M genotypes in colorectal cancer susceptibility.     

PARP-1基因多态性与胃癌易感性的关系

目的:探讨聚腺苷二磷酸核糖聚合酶-1(PARP-1)Val762Ala,Lys940Arg基因多态性与甘肃省地区汉族人群胃癌易感性的关系.方法:采用多重单碱基延伸SNP分型技术(Multiplex SNaPshot)对甘肃省胃癌高发区河西地区汉族人群中经病理确诊的原发性胃癌150例,健康对照组152例进行PARP-1基因2个SNP位点基因分型.使用ELISA法检测H.pylori感染.结果:发现PARP.1 940Lys/Arg基因型分布在胃癌组明显高于对照组(OR=2.917,95%CI:1.430-5.947.P=0.002);PARP-1762 Val/Ala基因型分布在胃癌组明显高于对照组(OR=1.685.95%CI:1.040-2.729,P=0.034).分层分析显示,在吸烟人群中,PARP-1 940Lys/Arg基因型携带者患胃癌的风险是Lys/Lys型携带者的8.430倍(OR=8.340;95%CI:2.664-26.144,P=0.000);在饮酒人群中,PARP-1 940Lys/Arg基因型携带者患胃癌的风险是Lys/Lys型携带者的3.333倍(OR=3.333,95%CI:1.214-9.155,P=0.015),在H.pylori感染阳性人群中,PARP-1 762A1a/Ala基因型携带者患胃癌的风险是Val/Val携带者的2.360倍(OR=2.360.95%CI:1.256-4.433,P=0.007).同时携带PARP-1 940 Lys/Arg和PARP-1 762Ala/Ala+Val/Ala基因型的个体患胃癌的发病风险是PARP-1 940Lys/Lys和PARP-1 762Val/Val基因型携带者的4.2倍(OR=4.200,95%CI:1.430-12.338.P=0.006).结论:PARP-1 940Lys/Arg和PARP-1 762Ala/Ala或Ala/Ala基因型与中国甘肃地区汉族人群胃癌发病风险增高相关;PARP-1 Lys940Arg 与吸烟,饮酒,PARP-1 Val762Ala与H.pylori感染以及PARP-1 Lys940Arg与PARP-1 Val762Ala在胃癌的发病风险中都各自存在着加乘交互效应.     

UGT1A1 gene polymorphism： Impact on toxicity and efficacy of irinotecan-based regimens in metastatic colorectal cancer

AIM: To investigate the correlation between uridine diphosphate glucuronosyl transferase 1A1 ( UGT1A1) gene polymorphisms and irinotecan-associated side effects and parameters of drug efficacy in patients with metastatic colorectal cancer (mCRC) receiving a lowdose weekly irinotecan chemotherapeutic regimen.METHODS: Genotypes were retrospectively evaluated by gene scan analysis on the ABI 310 sequencer of the TATAA box in the promoter region of the UGT1A1 gene in blood samples from 105 patients who had received 1st line irinotecan-based chemotherapy for mCRC.RESULTS: The distribution of the genotypes was as follows: wild type genotype (WT) ( 6/6) 39.0%,heterozygous genotype ( 6/7) 49.5%, and homozygous genotype ( 7/7) 9.5%. The overall response rate (OR) was similar between patients carrying the ( 6/7, 7/7) or the WT genotype ( 6/6) (44.3% vs 43.2%, P = 0.75).Neither time to progression [(TTP) 8.1 vs 8.2 mo, P = 0.97] nor overall survival [(OS) 21.2 vs 18.9 mo, P = 0.73] differed significantly in patients who carried the ( 6/6) when compared to the ( 6/7, 7/7) genotype. No significant differences in toxicity were observed: Grade 3 and 4 delayed diarrhoea [( 6/7, 7/7) vs ( 6/6); 13.0% vs 6.2%, P =0.08], treatment delays [( 6/7, 7/7) vs ( 6/6); 25.1% vs 19.3%, P = 0.24] or dose reductions [( 6/7, 7/7) vs ( 6/6); 21.5% vs 27.2%, P = 0.07].CONCLUSION: This analysis demonstrates the nonsignificant influence of the UGT1A1 gene polymorphism on efficacy and rate of irinotecan-associated toxicity in mCRC patients receiving low-dose irinotecan based chemotherapy.     

UGT1A1 gene polymorphism: Impact on toxicity and efficacy of irinotecan-based regimens in metastatic colorectal cancer

AIM: To investigate the correlation between uridine diphosphate glucuronosyl transferase 1A1 ( UGT1A1) gene polymorphisms and irinotecan-associated side effects and parameters of drug efficacy in patients with metastatic colorectal cancer (mCRC) receiving a lowdose weekly irinotecan chemotherapeutic regimen.METHODS: Genotypes were retrospectively evaluated by gene scan analysis on the ABI 310 sequencer of the TATAA box in the promoter region of the UGT1A1 gene in blood samples from 105 patients who had received 1st line irinotecan-based chemotherapy for mCRC.RESULTS: The distribution of the genotypes was as follows: wild type genotype (WT) ( 6/6) 39.0%,heterozygous genotype ( 6/7) 49.5%, and homozygous genotype ( 7/7) 9.5%. The overall response rate (OR) was similar between patients carrying the ( 6/7, 7/7) or the WT genotype ( 6/6) (44.3% vs 43.2%, P = 0.75).Neither time to progression [(TTP) 8.1 vs 8.2 mo, P = 0.97] nor overall survival [(OS) 21.2 vs 18.9 mo, P = 0.73] differed significantly in patients who carried the ( 6/6) when compared to the ( 6/7, 7/7) genotype. No significant differences in toxicity were observed: Grade 3 and 4 delayed diarrhoea [( 6/7, 7/7) vs ( 6/6); 13.0% vs 6.2%, P =0.08], treatment delays [( 6/7, 7/7) vs ( 6/6); 25.1% vs 19.3%, P = 0.24] or dose reductions [( 6/7, 7/7) vs ( 6/6); 21.5% vs 27.2%, P = 0.07].CONCLUSION: This analysis demonstrates the nonsignificant influence of the UGT1A1 gene polymorphism on efficacy and rate of irinotecan-associated toxicity in mCRC patients receiving low-dose irinotecan based chemotherapy.     

VEGF gene polymorphisms and susceptibility to colorectal cancer disease in Italian population

Background  The vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen involved in the process of angiogenesis, a crucial phase in tumor growth and metastasis. We carried out a case–control study to evaluate whether polymorphisms of VEGF gene modulate the risk of developing colorectal cancer disease (CCD). Materials and methods  We evaluated VEGF −2578A/C, −460T/C, and +405C/G genotypes obtained from a series of 302 CCD patients and 115 controls from the Italian population using polymerase chain reaction restriction fragment length polymorphism assay. Results  Strong linkage disequilibrium (LD) was detected between −2578A/C and −460T/C (D′ = 0.97; CI = 0.93–1) and between −2578A/C and +405C/G (D′ = 0.97; CI = 0.98–1) in the case group. Complete LD was detected between −2578A/C and +405C/G and between −460T/C and +405C/G (D′ = 1; CI = 0.84–1; CI = 0.82–1, respectively) in the control group. A reduced risk for the disease was associated with −2578C/A and −2578C/C (odds ratio (OR) = 0.34, CI = 0.162–0.676 and OR = 0.38, CI = 0.181–0.775, respectively). A direct association was found for carriers of the VEGF −460C/C polymorphism (OR = 3.55; CI = 1.659–8.469). We identified a protective haplotype −2578A, −460T, and +405G (OR = 0.04; CI = 0.009–0.19) and two different high-risk haplotypes −2578A, −460C, and +405G (OR = 1.90; CI = 1.31–2.27) and −2578C, −460C, and +405C (OR = 9.62; CI = 1.3–70.87). Conclusions  The present study suggests that the VEGF gene polymorphisms may play a role in the development of colorectal cancer. Paolo Maltese and Emanuele Canestrari contributed equally to the study.