Dihydropyrimidine dehydrogenase polymorphisms in patients with gastrointestinal malignancies and their impact on fluoropyrimidine tolerability: Experience from a single Italian institution

BACKGROUND Fluoropyrimidines are metabolized in the liver by the enzyme dihydropyrimidine dehydrogenase(DPD),encoded by the DPYD gene.About 7%of the European population is a carrier of DPYD gene polymorphisms associated with reduced DPD enzyme activity.AIM To assess the prevalence of DPYD polymorphisms and their impact on fluoropyrimidine tolerability in Italian patients with gastrointestinal malignancies.METHODS A total of 300 consecutive patients with a diagnosis of gastrointestinal malignancy and treated with a fluoropyrimidine-based regimen were included in the analysis and divided into two cohorts:(1)149 patients who started fluoropyrimidines after DPYD testing;and(2)151 patients treated without DPYD testing.Among the patients in cohort A,15%tested only the DPYD2A polymorphism,19%tested four polymorphisms(DPYD2A,HapB3,c.2846A>T,and DPYD13),and 66%tested five polymorphisms including DPYD6.RESULTS Overall,14.8%of patients were found to be carriers of a DPYD variant,the most common being DPYD6(12.1%).Patients in cohort A reported≥G3 toxicities(P=0.00098),particularly fewer nonhematological toxicities(P=0.0028)compared with cohort B,whereas there was no statistically significant difference between the two cohorts in hematological toxicities(P=0.6944).Significantly fewer chemotherapy dose reductions(P=0.00002)were observed in cohort A compared to cohort B,whereas there was no statistically significant differences in chemotherapy delay.CONCLUSION Although this study had a limited sample size,it provides additional information on the prevalence of DPYD polymorphisms in the Italian population and highlights the role of pharmacogenetic testing to prevent severe toxicity.

Activin A receptor type 1C single nucleotide polymorphisms associated with esophageal squamous cell carcinoma risk in Chinese population

BACKGROUND Transforming growth factor-β(TGF-β)superfamily plays an important role in tumor progression and metastasis.Activin A receptor type 1C(ACVR1C)is a TGF-βtype I receptor that is involved in tumorigenesis through binding to dif-ferent ligands.AIM To evaluate the correlation between single nucleotide polymorphisms(SNPs)of ACVR1C and susceptibility to esophageal squamous cell carcinoma(ESCC)in Chinese Han population.METHODS In this hospital-based cohort study,1043 ESCC patients and 1143 healthy controls were enrolled.Five SNPs(rs4664229,rs4556933,rs77886248,rs77263459,rs6734630)of ACVR1C were assessed by the ligation detection reaction method.Hardy-Weinberg equilibrium test,genetic model analysis,stratified analysis,linkage disequi-librium test,and haplotype analysis were conducted.RESULTS Participants carrying ACVR1C rs4556933 GA mutant had significantly decreased risk of ESCC,and those with rs77886248 TA mutant were related with higher risk,especially in older male smokers.In the haplotype analysis,ACVR1C Trs4664229Ars4556933Trs77886248Crs77263459Ars6734630 increased risk of ESCC,while Trs4664229Grs4556933Trs77886248Crs77263459Ars6734630 was associated with lower susceptibility to ESCC.CONCLUSION ACVR1C rs4556933 and rs77886248 SNPs were associated with the susceptibility to ESCC,which could provide a potential target for early diagnosis and treatment of ESCC in Chinese Han population.

Nucleotide excision repair gene polymorphisms and hepatoblastoma susceptibility in Eastern Chinese children:A five-center case-control study

Objective:Nucleotide excision repair(NER)plays a vital role in maintaining genome stability,and the effect of NER gene polymorphisms on hepatoblastoma susceptibility is still under investigation.This study aimed to evaluate the relationship between NER gene polymorphisms and the risk of hepatoblastoma in Eastern Chinese Han children.Methods:In this five-center case-control study,we enrolled 966 subjects from East China(193 hepatoblastoma patients and 773 healthy controls).The TaqMan method was used to genotype 19 single nucleotide polymorphisms(SNPs)in NER pathway genes,including ERCC1,XPA,XPC,XPD,XPF,and XPG.Then,multivariate logistic regression analysis was performed,and odds ratios(ORs)and 95%confidence intervals(95%CIs)were utilized to assess the strength of associations.Results:Three SNPs were related to hepatoblastoma risk.XPC rs2229090 and XPD rs3810366 significantly contributed to hepatoblastoma risk according to the dominant model(adjusted OR=1.49,95%CI=1.07−2.08,P=0.019;adjusted OR=1.66,95%CI=1.12−2.45,P=0.012,respectively).However,XPD rs238406 conferred a significantly decreased risk of hepatoblastoma under the dominant model(adjusted OR=0.68,95%CI=0.49−0.95;P=0.024).Stratified analysis demonstrated that these significant associations were more prominent in certain subgroups.Moreover,there was evidence of functional implications of these significant SNPs suggested by online expression quantitative trait loci(eQTLs)and splicing quantitative trait loci(sQTLs)analysis.Conclusions:In summary,NER pathway gene polymorphisms(XPC rs2229090,XPD rs3810366,and XPD rs238406)are significantly associated with hepatoblastoma risk,and further research is required to verify these findings.

Evaluation of angiotensin converting enzyme insertion/deletion, alpha adducin (ADD1) G460W, and IL-10 gene polymorphisms, and determination of prognostic effects in idiopathic sudden sensorineural hearing loss

Objective:The aim of this study was to examine angiotensin converting enzyme(ACE)insertion/deletion,alpha adducin,and interleukin-10(IL-10)gene polymorphisms(GPs)in terms of both idiopathic sudden sensorineural hearing loss(ISSNHL)risk and their potential prognostic effects.Methods:The study group consisted of 70 patients and the control group consisted of 50 patients.Venous blood samples were analyzed for relevant GPs via kompetitive allele-specific polymerase chain reaction.Age,sex,affected side,tinnitus,and vertiginous symptom status,number of days between symptom onset and hospital admission,pure tone audiometry results at admission and after treatment were included in the study.Data were compared statistically.Results:The D allele of ACE insertion/deletion GP was significantly more frequent in patients with ISSNHL than in the control group(p=0.032).II genotype was associated with a reduced risk of ISSNHL(p=0.036).The amount of hearing loss was significantly higher in patients with the TT genotype(p=0.027)and T allele of the IL-10 GP(p=0.035)than in the patients without this allele.Severe hearing loss was a poor prognostic factor(p=0.008).Conclusions:The D allele of ACE insertion/deletion GP may be involved in the ISSNHL etiology.Due to the association of this allele with occlusive vascular pathologies,ischemia is believed to be a common pathway in the etiopathogenesis of ISSNHL.

Distribution of gene polymorphisms associated with aspirin antiplatelet in the Han NSTEMI population

Objective:To analyze the genotype and allele distribution characteristics of GPⅢa PLA2(rs5918),PEAR1(rs12041331),and PTGS1(rs10306114)genes related to the antiplatelet pharmacological effects of aspirin,providing reference for individualized treatment of Chinese Han NSTEMI patients.Methods:A total of 107 Han patients with NSTEMI in Beijing Luhe Hospital affiliated to Capital Medical University from January 2016 to December 2022 were selected as the research subjects.The genotypes of GPⅢa PLA2(rs5918),PEAR1(rs12041331)and PTGS1(rs10306114)were detected by fluorescence staining in situ hybridization.The frequency distribution and allele distribution of genotype were analyzed.The results were analyzed whether there were statistical differences in the distribution of related alleles between the Han NSTEMI population and some populations in the 1000 Genomes database.Results:In the Han NSTEMI population,the genotype frequencies of GPⅢa PLA2(rs5918)locus were TT 97.20%,TC 2.80%and CC 0%,the allele frequencies were T 98.60%and C 1.40%.The genotype frequencies of PEAR1(rs12041331)locus were GG 42.06%,GA 44.86%and AA 13.08%,the allele frequencies were G 64.49%and A 35.51%.The genotypes at the PTGS1(rs10306114)locus were all AA(100%),no AG or GG genotype was found.Conclusion:In the NSTEMI population of Han nationality,the mutation at GPⅢa PLA2(rs5918)site related to aspirin antiplatelet pharmacology is rare,and there is no mutation at PTGS1(rs10306114)site.Wild homozygotes are dominant in these two gene loci,while mutations in PEAR1(rs12041331)are more common.Some of the findings in this study are similar to those in previous reports or other populations included in the relevant database;however,some results differ from previous reports or other populations。

Cytokine and apoptosis gene polymorphisms influence the outcome of hepatitis C virus infection

BACKGROUND:Hepatitis C virus (HCV) infection is thought to be chronic and the factors leading to viral clearance or persistence are poorly understood.This study was undertaken to investigate the possibility of a significant relationship between the spontaneous clearance or the persistence of hepatitis C virus (HCV) infection and cytokine and apoptosis gene polymorphisms in Tunisian patients on hemodialysis.METHODS:Polymorphisms of the genes IL-1 (-889 IL-1α,-511 and +3954 IL-1β,IL-1Ra),IL-18 (-137 and-607),IL-12 (-1188) and Apo1/Fas (-670) were determined by PCR-RFLP,PCR-SSP and PCR-VNTR in 100 healthy blood donors and 100 patients infected with HCV and undergoing hemodialysis.The patients were classified into two groups:G1 consisted of 76 active chronic hepatitis patients (positive for HCV RNA) and G2 consisted of 24 hemodialysed patients who spontaneously eliminated the virus (negative for HCV RNA).RESULTS:The frequency of genotype association [-137GC/-607CA] IL-18 was higher in G2 (41.7%) than in G1 (15.8%) (P=0.008;OR=0.26;95% CI,0.10-0.73).We also found a higher frequency of the AA genotype of the Apo1/Fas gene in G2 (41.6%) than in G1 (17.5%) (P=0.026;OR=3.49;95% CI,1.13-10.69).Adjustment for known covariate factors (age,gender and genotype) confirmed these univariate findings and revealed that the genotype association GC-CA of the (-137 and-607) IL-18 gene and the AA genotype of the Apo1/Fas gene were associated with the clearance of HCV (P=0.041 and 0.017,respectively).CONCLUSION:The two genotypes GC-CA of the (-137 and-607) IL-18 polymorphism and the AA genotype of the Apo1/Fas gene influence the outcome of HCV infection in Tunisian patients on hemodialysis.

Research on the Correlation Between rs2110385 Polymorphisms of the Visfatin Gene and Nonproliferative Diabetic Retinopathy

Objective:To investigate the association between rs2110385 polymorphisms of the visfatin gene and the risk of type 2 diabetic retinopathy(DR).Methods:172 Han subjects were selected from Xi’an Shaanxi Province;140 patients with type 2 diabetes mellitus(T2DM)and 32 normal controls(NC)were selected from our hospital.Patients with diabetes were divided into a non-DR group(T2DM)(n=69)and a nonproliferative diabetic retinopathy Group(DR)(n=71)after dilated fundus photography and fundus fluorescein angiography.rs2110385/AluⅠgenotypes were detected by standardized polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP),and the differences in the detection rates of different genotypes in the above populations were compared.Results:1)The visfatin level in the DR Group was significantly higher than that in the NC and T2DM groups(P<0.05).2)The frequency of GG genotype and G allele of rs2110385 in the DR Group were higher than those in the T2DM and NC groups(80.3,69.6,50.0,86.6,79,65.6,P<0.05).3)There were significant differences in allele frequency and genotype frequency distribution of rs2110385 between the DR Group and the NC group(P<0.01).Conclusion:Visfatin increased in the nonproliferative diabetic retinopathy group and could be a potential indicator for the clinical prediction of DR.The G allele of the rs2110385 polymorphic site may be related to the risk of DR.

Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence

Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were collected.Fourteen SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic regression.The multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)modeling.Results Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 rs1053605.Carriers of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased risk.CCL2 rs4586 and MMP-2 rs14070 exhibited the most significant interactions.Conclusion CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS.

Role of gene polymorphisms in gastric cancer and its precursor lesions:Current knowledge and perspectives in Latin American countries

Latin America shows one of the highest incidence rates of gastric cancer in the world,with variations in mortality rates among nations or even within countries belonging to this region.Gastric cancer is the result of a multifactorial complex process,for which a multistep model of carcinogenesis is currently accepted.Additionally to the infection with Helicobacter pylori,that plays a major role,environmental factors as well as genetic susceptibility factors are significant players at different stages in the gastric cancer process.The differences in population origin,demographic structure,socio-economic development,and the impact of globalization lifestyles experienced in Latin America in the last decades,all together offer opportunities for studying in this context the influence of genetic polymorphisms in the susceptibility to gastric cancer.The aim of this article is to discuss current trends on gastric cancer in Latin American countries and to review the available published information about studies of association of gene polymorphisms involved in gastric cancer susceptibility from this region of the world.A total of 40 genes or genomic regions and69 genetic variants,58%representing markers involved in inflammatory response,have been used in a number of studies in which predominates a low number of individuals(cases and controls)included.Polymorphisms of IL-1B(-511 C/T,14 studies;-31 T/C,10 studies)and IL-1RN(variable number of tandem repeats,17 studies)are the most represented ones in the reviewed studies.Other genetic variants recently evaluated in large metaanalyses and associated with gastric cancer risk were also analyzed in a few studies[e.g.,prostate stem cell antigen(PSCA),CDH1,Survivin].Further and better analysis centered in gene polymorphisms linked to other covariates,epidemiological studies and the information provided by meta-analyses and genome-wide association studies should help to improve our understanding of gastric cancer etiology in order to develop appropriate health programs in Latin America.

The Relationship between Genetic Polymorphisms of Three Gene Loci and Growth Characters of Haimen Goats

[Objective] The paper aims to study the relationship between genetic polymorphisms of three gene loci and growth character of Haimen Goats to provide reference to promote Haimen Goat growth character and cultivate Haimen Goat new strain of fast-growth.[Method] We processed analysis and related statistical analysis on three gene loci of Haimen Goats with PCR-RFLP and PCR-SSCP.[Result] The results suggested that there were two genotypes in MSTN gene IntronⅡ,GH gene exonⅠ and GH gene exonⅡ in Haimen Goats.Different genotypes of these gene loci had different effects on relative growth character of Haimen Goats.[Conclusion] This study had a significant meaning about promoting Haimen Goat avoirdupois by marker assistant option.

Association of Polymorphisms of Leptin Gene with Body Weight and Body Sizes Indexes in Chinese Indigenous Cattle

PCR-SSCP was used to analyze the polymorphism of leptin gene in 539 samples of six cattle breeds, namely Nanyang （NY）, Qinchuan （QC）, Jiaxianred （JXR）, Xizhen （XZ）, Luxi （LX）, and Holstein cow （HOL） breeds. PCR products with a 330 bp were amplified and sequenced. The results showed that the frequencies of alleles A/B of NY, QC, JXR, XZ, LX, and HOL breeds were 0.558/0.442, 0.492/0.508, 0.571/0.429, 0.658/0.342, 0.591/0.409, and 0.615/0.385, respectively. The association of variations of leptin gene with growth traits in NY, QC, JXR breeds was analyzed. Some indexes of the individuals with genotype BB were higher than that with genotype AA and AB in NY breed, such as the indexes of body length, heart length, body weight, hucklebone width, body height, and average day gain. The height at hip cross of the individuals with genotype BB was higher than that of those with genotype AA and AB in QC breed （P 〈 0.05）. So leptin gene may be one of the candidate genes for growth traits with height at hip cross, but not for body weight, heart length, and body length trait. However, the height at hip cross and hucklebone width of the individuals with genotype AB and BB were higher than that of those with genotype AA in JXR breed （P 〈 0.05）, but the difference was not statistically significant in body weight and body sizes （body height, body length, and heart length）. And the polymorphisms in leptin gene were caused by G→T transversion at the 66th bp position, A→C transversion at the 67th bp position and G→T transversion at the 299th bp position. These results may be applied to marker-assisted selection of Chinese cattle breeds.

ApoB-100, ApoE and CYP7A1 gene polymorphisms in Mexican patients with cholesterol gallstone disease

AIM: To determine the possible association of the ApoB100 (Xba Ⅰ ), ApoE (Hha Ⅰ ) and CYP7A1 (Bsa Ⅰ ) gene polymorphisms, with the development of cholesterol gallstone disease (GD) in a Mexican population. METHODS: The polymorphisms were analyzed by polymerase chain reaction followed by restriction fragment length polymorphism, in two groups matched by ethnicity, age and sex: patients with GD (n = 101) and stone-free control subjects (n = 101). RESULTS: Allelic frequencies in patients and controls were: 34.16% vs 41.58% (P = 0.124) for X+of ApoB-100; 4.46% vs 5.94% (P = 0.501) for E2, 85.64% vs 78.22% (P = 0.052) for E3, 9.90% vs 15.84% (P = 0.075) for E4 of ApoE; and 25.74% vs 27.72% (P = 0.653) for C of CYP7A1. Differences in genotypic frequencies between the studied groups were not significant (P < 0.05). CONCLUSION: These results demonstrated that no association exists between the studied polymorphisms and cholelithiasis in this high prevalent population.

Polymorphisms of MTHFR and susceptibility to oesophageal adenocarcinoma in a Caucasian United Kingdom population

AIM: To identify if methylene tetra-hydrofolatereductase (MTHFR) C677T polymorphisms are associated with oesophageal adenocarcnomas in a Caucasian population and to test whether folic acid and homocysteine levels are linked with cancer risk.

Increased Risk of Acute Myeloid Leukemia in Patients with CYP1A1 Polymorphisms

Acute Myeloid Leukemia (AML) is a group of genetically diverse hematopoietic malignancies arising from cell progenitors developing in the myeloid pathway or from primitive stem cells. Genetic susceptibility of AML may account for an increased risk of AML due to partial metabolism of or biocativation of carcinogens. Chemical compounds are metabolized by a two-tiered phase detoxifying system. Polymorphisms in these pathways may lead to DNA damage and development of AML. We determined the frequencies of carcinogen metabolism gene polymorphisms (CYP1A1, del{GSTM1} and del{GSTT1}) in a case control-study based on polymorphism analysis. Fifty-eight consecutively AML patients (median age 62 years) and 174 sex and age-matched control group were assessed by a PCR-RFLP assay. There were 51 de novo and 7 secondary AML. CYP1A1*2A and CYP1A1*2C polymorphisms were more frequent in CG than AML p 0.001 and in contrast, CYP1A1*3 and CYP1A1*4 were more frequent in AML than CG p 0.001. There were no differences in del{GSTM1} neither del{GSTT1} between AML and CG (p = 0.999 and p = 0.539). Odds ratio for AML in patients harboring CYP1A1*3 was 2.36 (95% CI 1.2 - 4.5), 2.38 for CYP1A1*4 (95% CI 0.8 - 6.8). Adjusted OR was 2.63 for CYP1A1*3 (95% CI 1.4 - 5.1) and 2.66 for CYP1A1*4 (95% CI 0.9 - 7.8). In the multivariate analysis CYP1A1*3 polymorphism was a risk factor for AML with an OR for 3.99 (95%CI 1.9 - 8.6). To the best of our knowledge this is the first study to show that CYP1A1*3 heterozygous genotypes increase the risk of AML. Our data support that inherited absence of this carcinogen detoxification pathway may be an important determinant of AML.

Vitamin D receptor gene polymorphisms and hepatocellular carcinoma in alcoholic cirrhosis

AIM: To assess the relationship between vitamin D re-ceptor (VDR) gene polymorphisms and the presence of hepatocellular carcinoma (HCC). METHODS: Two-hundred forty patients who underwent liver transplantation were studied. The etiologies of liver disease were hepatitis C (100 patients), hepatitis B (37) and alcoholic liver disease (103). A group of 236 healthy subjects served as controls. HCC in the explanted liver was detected in 80 patients. The following single nucle-otide gene polymorphisms of the VDR were investigatedby polymerase chain reaction and restriction fragment length polymorphism: FokI C>T (F/f), BsmI A>G (B/b), ApaI T>G (A/a) and TaqI T>C (T/t) (BAT). RESULTS: The frequencies of genotypes in patients without and with HCC were for FokI F/F = 69, F/f = 73, f/f = 18 and F/F = 36, F/f = 36, f/f = 8; BsmI b/b = 45, B/b = 87, B/B = 28 and b/b = 33, B/b = 35, B/B = 12; for ApaI A/A = 53, A/a = 85, a/a = 22 and A/A = 27, A/a = 38, a/a = 15; for TaqI T/T = 44, T/t = 88, t/t = 28 and T/T = 32, T/t = 38, t/t = 10. Carriage of the b/b genotype of BsmI and the T/T genotype of TaqI was signif icantly associated with HCC (45/160 vs 33/80, P < 0.05 and 44/160 vs 32/80, P < 0.05, respectively). The absence of the A-T-C protective allele of BAT was signif i-cantly associated with the presence of HCC (46/80 vs 68/160, P < 0.05). A strong association was observed between carriage of the BAT A-T-C and G-T-T haplotypes and HCC only in alcoholic liver disease (7/46 vs 12/36 vs 11/21, P < 0.002, respectively).CONCLUSION: VDR genetic polymorphisms are sig-nificantly associated with the occurrence of HCC in patients with liver cirrhosis. This relationship is more specific for patients with an alcoholic etiology.

Interleukin-10 promoter polymorphisms in patients with hepatitis B virus infection or hepatocellular carcinoma in Chinese Han ethnic population

BACKGROUND: Since single nucleotide polymorphisms (SNPs) can serve as gene markers, polymorphism profiles may help scientists to identify the full collection of genes that contribute to the development of complex diseases such as cancer. The distribution of interleukin-10 (IL-10) promoter polymorphisms in Chinese Han ethnic patients with hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) was investigated in this study. METHODS: The polymorphisms of IL-10 promoter region were detected by pulymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing. Sixty-six health controls, 42 patients with HBV infection, 30 HCC patients, and cell line SMMC-7721 were examined this way. RESULTS: Polyrnorphisms of T/C or T/N on-872 site occurred frequently in Han ethnic population. Pulyrnorphisms were detected in HBV and HCC patients and cell line SMMC-7721. The hotspot among the pulymorphisms was inserting base A between-1058 and-1057. CONCLUSION: Polymorphisms of IL-10 promoter in HBV and HCC patients may be associated with HBV infection and HCC development.

Association between polymorphisms of APE1 and OGG1 and risk of colorectal cancer in Taiwan

AIM: To evaluate the effects of OGG1(Ser326Cys, 11657A/G, and Arg154His) and APE1(Asp148Glu, and T-656G) polymorphisms on colorectal cancer(CRC) risk.METHODS: We enrolled 727 cases newly diagnosed with colorectal adenocarcinoma and 736 age- and sex-matched healthy controls from a medical center in Taiwan. Genomic DNA isolated from the buffy coat was used for genotyping through polymerase chain reaction. Unconditional logistic regressions were used for calculating ORs and 95%CIs to determine the association between the genetic polymorphisms and CRC risk. Haplotype frequencies were estimated using PHASE software. Moreover, stratification analyses onthe basis of sex, age at diagnosis, and tumor subsite and stage were performed.RESULTS: The CRC risk was higher in patients with the OGG1 326Ser/Cys + Cys/Cys genotype(OR = 1.38, 95%CI: 1.03-1.85, P = 0.030), particularly high in patients with stage Ⅲ + Ⅳ cancer(OR = 1.48, 95%CI: 1.03-2.13) compared with patients with the Ser/Ser genotype. In addition, OGG1 11657 G allele carriers had a 41% reduced CRC risk among stage 0-Ⅱ patients(OR = 0.59, 95%CI: 0.35-0.98). The CRC risk was significantly higher among females with the APE1 Glu allele(OR = 1.41, 95%CI: 1.02-1.96). The APE1 148Glu/-656 G haplotype was also associated with a significant CRC risk in females(OR = 1.36, 95%CI: 1.03-1.78).CONCLUSION: OGG1 and APE1 polymorphisms are associated with stage- and sex-specific risk of CRC in the Taiwan Residents population.

Role of peroxisome proliferator-activated receptors gene polymorphisms in type 2 diabetes and metabolic syndrome

Metabolic syndrome(MetS) and type 2 diabetes mellitus(T2DM) are the serious public health problems worldwide.Moreover,it is estimated that MetS patients have about five-fold greater risk of the T2 DM development compared with people without the syndrome.Peroxisome proliferator-activated receptors are a subgroup of the nuclear hormone receptor superfamily of ligand-activated transcription factors which play an important role in the pathogenesis of MetS and T2 DM.All three members of the peroxisome proliferator-activated receptor(PPAR) nuclear receptor subfamily,PPARα,PPARp/5 and PPARγ are critical in regulating insulin sensitivity,adipogenesis,lipid metabolism,and blood pressure.Recently,more and more studies indicated that the gene polymorphism of PPARs,such as Leu^(162)Val and Val^(227)Ala of PPARα,+294T> C of PPARβ/δ,Pro^(12)Ala and C1431 T of PPARγ,are significantly associated with the onset and progressing of MetS and T2 DM in different population worldwide.Furthermore,a large body of evidence demonstrated that the glucose metabolism and lipid metabolism were influenced by gene-gene interaction among PPARs genes.However,given the complexity pathogenesis of metabolic disease,it is unlikely that genetic variation of a single locus would provide an adequate explanation of inter-individual differences which results in diverse clinical syndromes.Thus,gene-gene interactions and gene-environment interactions associated with T2 DM and MetS need future comprehensive studies.

Polymorphisms in base excision repair genes: Breast cancer risk and individual radiosensitivity

Breast cancer(BC) is the most common cancer among women worldwide. The aetiology and carcinogenesis of BC are not clearly defined, although genetic, hormonal, lifestyle and environmental risk factors have been established. The most common treatment for BC includes breast-conserving surgery followed by a standard radiotherapy(RT) regimen. However, radiation hypersensitivity and the occurrence of RT-induced toxicity in normal tissue may affect patients' treatment. The role of DNA repair in cancer has been extensively investigated, and an impaired DNA damage response may increase the risk of BC and individual radiosensitivity. Single nucleotide polymorphisms(SNPs) in DNA repair genes may alter protein function and modulate DNA repair efficiency, influencing the development of various cancers, including BC. SNPs in DNA repair genes have also been studied as potential predictive factors for the risk of RT-induced side effects. Here, we review the literature on the association between SNPs in base excision repair(BER) genes and BC risk. We focusedon X-ray repair cross complementing group 1(XRCC1), which plays a key role in BER, and on 8-oxoguanine DNA glycosylase 1, apurinic/apyrimidinic endonuclease 1 and poly(ADP-ribose) polymerase-1, which encode three important BER enzymes that interact with XRCC1. Although no association between SNPs and radiation toxicity has been validated thus far, we also report published studies on XRCC1 SNPs and variants in other BER genes and RT-induced side effects in BC patients, emphasising that large well-designed studies are needed to determine the genetic components of individual radiosensitivity.

Role of polymorphisms in genes that encode cytokines and Helicobacter pylori virulence factors in gastric carcinogenesis

The Helicobacter pylori(H. pylori) infection is a determinant factor in gastric cancer(GC) development. However, the infection outcomes are variable and depend on both host and bacterial characteristics. Some host cytokines such as interleukin(IL)-1β, IL-1 Ra, IL-8, IL-10 and tumor necrosis factor-α play important roles in the host immune system response to the pathogen, in the development of gastric mucosal lesions and in cell malignant transformation. Therefore, these host factors are crucial in neoplastic processes. Certain polymorphisms in genes that encode these cytokines have been associated with an increased risk of GC. On the other hand, various virulence factors found in distinct H. pylori bacterial strains, including cytotoxinassociated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and blood group antigen binding adhesin, have been associated with the pathogenesis of different gastric diseases. The virulent factors mentioned above allow the successful infection by the bacterium and play crucial roles in gastric mucosa lesions, including malignant transformation. Moreover, the role of host polymorphisms and bacterial virulence factors in gastric carcinogenesis seems to vary among different countries and populations. The identification of host and bacterium factors that are associated with an increased risk of GC development may be useful in determining the prognosis of infection in patients, what could help in clinical decision-making and in providing of an optimized clinical approach.