rs4779584 C/T、rs4444235 T/C单核苷酸多态性与江苏泰州地区结直肠癌的发病风险研究

目的 了解单核苷酸多态性（SNP）与泰州地区人群中结直肠癌发病的关系。方法 收集泰州人民医院的76例结肠癌、84例直肠癌患者外周血样本作为疾病组,另选170例健康体检正常人群外周血样本作为对照组,选取与结直肠癌高度相关的SNP位点（rs4779584和rs4444235）进行检测,分析不同基因型和等位基因分布情况及其与结直肠癌总体和不同部位的患病风险。结果 两组rs4779584 C/T和rs4444235 T/C基因型分布均符合Hardy-Weinberg平衡。疾病组rs4779584 C/T和rs4444235 T/C的基因型和等位基因分布与对照组相比,差异均有统计学意义（P<0.05）。rs4779584 C/T中,以CC基因型为参照,CT和TT基因型与结直肠癌的患病风险无关联;以CC+CT基因型为参照,TT基因型的结直肠癌患病风险升高,以C等位基因为参照,T等位基因的结直肠癌患病风险升高,差异均有统计学意义（P<0.05）。rs4444235 T/C中,以TT、TT+TC基因型为参照,CC基因型的结直肠癌患病风险均升高;以T等位基因为参照,C等位基因的结直肠癌的患病风险升高,差异均有统计学意义（P<0.05）。结论 在江苏泰州地区人群中,rs4779584和rs4444235 位点SNP与结直肠肿瘤发病风险高度相关。     

Is there an Association between Variants in Candidate Insulin Pathway Genes IGF-I,IGFBP-3, INSR,and IRS2 and Risk of Colorectal Cancer in the Iranian Population?

Background: Several epidemiological studies have shown associations between colorectal cancer (CRC) riskand type 2 diabetes and obesity. Any effects would be expected to be mediated through the insulin pathway.Therefore it is possible that variants of genes encoding components of the insulin pathway play roles in CRCsusceptibility. In this study, we hypothesized that polymorphisms in the genes involving the insulin pathway areassociated with risk of CRC. Materials and Methods: The associations of four single nucleotide polymorphisms(SNPs) in IGF-I (rs6214), IGFBP-3 (rs3110697), INSR (rs1052371), and IRS2 (rs2289046) genes with the riskof CRC were evaluated using a case–control design with 167 CRC cases and 277 controls by the PCR–RFLPmethod. Results: Overall, we observed no significant difference in genotype and allele frequencies between thecases and controls for the IGF-I, IGFBP-3, INSR, IRS2 gene variants and CRC before or after adjusting forconfounders (age, BMI, sex, and smoking status). However, we observed that the IRS2 (rs2289046) GG genotypecompared with AA+AG genotypes has a protective effect for CRC in normal weight subjects (p=0.035, OR=0.259,95%CI= 0.074-0.907). Conclusions: These findings do not support plausible associations between polymorphicvariations in IGF-I, IGFBP-3, INSR, IRS2 genes and risk of CRC. However, the evidence for a link betweenthe IRS2 (rs2289046) variant and risk of CRC dependent on the BMI of the subjects, requires confirmation insubsequent studies with greater sample size.     

RPSA Gene Mutants Associated with Risk of Colorectal Cancer among the Chinese Population

The primary aim of this study was to evaluate the relationship of single nucleotide polymorphisms (SNPs) inribosomal protein SA (RPSA) gene with colorectal cancer (CRC). A case-control study including 388 controls and387 patients with CRC was conducted in a Chinese population. Information about socio-demography and livingbehavior factors was collected by a structured questionnaire. Three SNPs (rs2133579, rs2269349, rs7641291)in RPSA gene were genotyped by Illumina SnapShot method. Multiple logistic regression models were used forassessing the joint effects between tea consumption and SNPs on CRC. The subjects with rs2269349 CC genotypehad a decreased risk for CRC (OR=0.60; 95%CI = 0.37-0.99), compared with TT/CT genotype after adjustmentfor covariates. A similar association of rs2269349 with rectal cancer was observed (OR=0.49; 95%CI=0.24-1.00).Further analyses indicated that this SNP could modify the protective effect of tea drinking on CRC. Amongthe subjects with rs2269349 TT/CT or rs2133579 AA/GA, there was a marginal significantly lower risk of CRC(OR and 95%CI: 0.63 and 0.39-1.01 for rs2269349; 0.64 and 0.40-1.02 for rs2133579) in tea-drinking subjects incomparison to non-tea-drinking subjects. Mutants in the RPSA gene might be associated with genetic susceptibilityto CRC and influence the protective effect of tea consumption in the Chinese population.     

Association of estrogen receptor beta variants and serum levels of estradiol with risk of colorectal cancer: a case control study

ABSTRACT: BACKGROUND: Endogenous estrogens may play a vital role in colorectal tumorigenesis. Estrogen receptor beta is the predominant subtype which mediates the biological effect of estrogens, while loss of expression of estrogen receptor beta has been indicated as a common step in the development of colorectal cancer (CRC). Epidemiological studies have revealed several functional polymorphisms of estrogen receptor beta (ESR2) for cancer risk, but relevant study in CRC is limited, particularly in men. This study aimed to investigate the association of circulating estradiol and variations of ESR2 with CRC risk in men. METHODS: We initiated a case-control study consisting of 390 patients with CRC and 445 healthy controls in men only. We genotyped ESR2 single nucleotide polymorphisms (SNPs) rs1256049 and rs4986938 and measured serum estradiol concentration using chemilluminescence immunoassay. Multivariable logistic regression model was performed to evaluate the associations between these variables and CRC risk. RESULTS: ESR2 rs1256049 CT/TT genotypes were associated with reduced risk of CRC (odds ratio [OR], 0.7, 95% confidence interval [CI], 0.5-1.0), while rs4986938 CT/TT genotypes were associated with increased risk of CRC (OR, 1.5, 95% CI, 1.0-2.1). In addition, the CRC risk increased with the number of risk genotypes of these two SNPs in a dose-response manner (Ptrend, 0.003). Specifically, subjects carrying risk genotypes of both SNPs had the highest risk of CRC (OR, 2.0, 95% CI, 1.3-3.3.). Moreover, serum estradiol concentration alone was associated with risk of CRC in men (OR, 1.2, 95% CI, 1.0-1.3). However, individuals presenting both rs4986938 CT/TT genotypes and high level of serum estradiol had a high risk of CRC (OR, 2.3, 95% CI, 1.4-3.9), compared with those presenting CC genotype and low level of serum estradiol. The similar joint results were not observed for SNP rs1256049. CONCLUSIONS: These results suggest that endogenous estrogen and genetic variations in ESR2 may individually, or more likely jointly, affect CRC risk in male Han Chinese population, while larger studies are needed to validate our findings.     

Parathyroid Hormone Gene rs6256 and Calcium Sensing Receptor Gene rs1801725 Variants are not Associated with Susceptibility to Colorectal Cancer in Iran

Background: Substantial evidence from epidemiological studies has suggested that increased levels of calcium may play a protective role against colorectal cancer (CRC). Given the vital role of calcium sensing receptor (CaSR) and parathyroid hormone (PTH) in the maintenance of calcium homeostasis, we explored whether the rs1801725 (A986S) variant located in exon 7 of the CaSR gene and the rs6256 variant located in exon 3 of PTH gene might be associated with CRC risk. Materials and Methods: In this study 860 subjects including 350 cases with CRC and 510 controls were enrolled and genotyped using PCR-RFLP methods. Results: We observed no significant difference in genotype or allele frequencies between the cases with CRC and controls for both CaSR and PTH genes either before or after adjustment for confounding factors including age, BMI, sex, smoking status, and family history of CRC. Furthermore, no evidence for effect modification of any association of rs1801725 and rs6256 variants and CRC by BMI, sex, or tumor site was observed. In addition, there was no significant difference in genotype and allele frequencies between the normal weight (BMI <25 kg/m2) cases and overweight/ obese (BMI ≥25 kg/m2) cases for the two SNPs. Conclusions: These data indicated that the CaSR gene A986S variant is not a genetic contributor to CRC risk in the Iranian population. Furthermore, our results suggest for the first time that PTH gene variant does not affect CRC risk. Nonetheless, further studies with larger sample size are needed to validate these findings.     

Tag SNPs in long non-coding RNA H19 contribute to susceptibility to gastric cancer in the Chinese Han population

Long non-coding RNA (lncRNA) H19 is involved in tumor development, progression, and metastasis. This case-control study assessed the association between H19 genetic variants and susceptibility to gastric cancer (GC) in a Chinese Han population. We genotyped four lncRNA H19 single nucleotide polymorphisms (SNPs) (rs217727 C > T, rs2839698 C > T, rs3741216 A > T, rs3741219 T > C) in 500 GC patients and 500 healthy controls. Carriers of variant rs217727T and rs2839698T alleles showed increased GC risk (P = 0.008 and 0.011, respectively). Compared with the common genotype, CT + TT rs217727 and CT + TT rs2839698 genotypes were associated with significantly increased GC risk (P = 0.040, adjusted odds ratio [OR] = 1.32, 95% confidence interval [CI] = 1.01–1.71; P = 0.033, adjusted OR = 1.31, 95% CI = 1.02–1.69, respectively). Further stratified analyses revealed that the association between GC risk and variant genotypes of rs217727 was more profound in younger individuals (≤59 years) and non-smokers, while the association between risk and the rare rs2839698 genotype persisted in men and rural subjects. rs2839698 CT and TT genotypes were also associated with higher serum H19 mRNA levels compared with the CC genotype. These findings suggest that lncRNA H19 SNPs may contribute to susceptibility to GC.     

Common genetic variation in the <Emphasis Type="Italic">IGF-1</Emphasis> gene,serum IGF-I levels and breast density

Introduction High breast density is one of the strongest known risk factors for developing breast cancer. Insulin-like growth factor I (IGF-I) is a strong mitogen and has been suggested to increase breast cancer risk by increasing the amount of dense tissue in the female breast. Objectives We wanted to investigate the effect of common variation in the IGF-1 gene on serum IGF-I levels and on breast density. Design and methods Mammograms and blood samples of 1,928 premenopausal participants of the Dutch Prospect-EPIC cohort were collected at baseline. Using a haplotype tagging approach, 16 single nucleotide polymorphisms (SNP) from three blocks covering the IGF-1 gene were genotyped in all study participants. Breast density was assessed using a quantitative computer-assisted method. For a subgroup of women, who went through menopause within 5 years after recruitment (n = 656), premenopausal IGF-I levels and additionally postmenopausal breast density were determined. False positive report probabilities (FPRP) for statistically significant relations were calculated using the Wacholder method. Results The minor alleles of five SNPs in block 3 were significantly associated with elevated levels of IGF-I (rs9989002, rs2033178, rs7136446, rs978458, rs6220; P-values: 0.01–0.04). The same SNPs were related with modestly higher percent breast density before menopause and—in the subgroup of women that became postmenopausal during follow-up—with a modestly higher percent breast density after menopause. The most significant result, i.e. the relation between rs6220 and IGF-I levels, had an FPRP  <0.5 assuming prior probabilities of 0.01 and higher. Conclusion Common genetic variation in the IGF-1 gene is related to circulating levels of IGF-I, but the relationship with breast density is indecisive.     

Common genetic variation of insulin-like growth factor-binding protein 1 (IGFBP-1), IGFBP-3, and acid labile subunit in relation to serum IGF-I levels and mammographic density

Mammographic density is strongly related to increased breast cancer risk. Accumulating evidence indicates that a role for the IGF-pathway in mammographic density and breast cancer development. Here, we investigate whether common genetic variation in this pathway influences insulin-like growth factor-I (IGF-I) levels and mammographic density. In 1,916 premenopausal women within the Prospect-EPIC cohort, we examined associations of 14 haplotype tagging SNPs in the ALS, IGFBP1, and IGFBP3 genes with IGF-I circulating levels and mammographic density. In 657 women, who became postmenopausal during follow-up, we investigated how these SNPs were related with the decrease in density over menopause. Linear regression models were used for statistical analysis. None of the ALS or IGFBP3 SNPs were statistically significantly associated with IGF-I levels or mammographic density. The CC genotype for rs1908751 (IGFBP1) was associated with lower levels of IGF-I (110.9 ng/ml) compared to the CT/TT genotypes (115.7 ng/ml) (P = 0.04). Women with the CC genotype also had lower percent density, although not statistically significantly (P = 0.12). Women carrying the AA genotype for rs1995051 (IGFBP1) showed that borderline significantly lower IGF-I levels (P = 0.06) and significantly lower mammographic density (40.3% compared to 43.5% in the GG/GA genotypes; P = 0.05). No relationships were found for any of the SNPs in relation with changes in breast density over menopause. These findings suggest that common genetic variation in the IGFBP1 gene is weakly related to IGF-I levels and mammographic density. Our results do not provide support for such a role of genetic variants in the IGFBP3 and ALS genes.     

Lack of Association of Three Common Polymorphisms in Toll-like receptors (TLRs), TLR2+597T>C, +1350C>T and Arg753Gln with Cancer Risk: a Meta-analysis

Background: Single nucleotide polymorphisms (SNPs) occurring in Toll-like receptors (TLRs) may contributeto cancer risk. Many polymorphisms of TLR2 have been studied for associations, but the findings are conflicting.Methodology/Principal Findings: We performed a meta-analysis of 14 studies to confirm the association betweenTLR2+597T>C (rs3804099), +1350C>T (rs3804100) and Arg753Gln (rs5743708) polymorphisms and cancerrisk. Odds ratio (OR) and 95% confidence intervals (95% CI) were used to assess the strength of associations.There was no significant association between TLR2+597T>C and cancer risk in the codominant models (CCvs. TT: OR = 1.01, 95%CI = 0.86-1.17, Pheterogeneity = 0.148; CT vs. TT: OR = 0.92, 95%CI = 0.69-1.23, Pheterogeneity< 0.001), the recessive model (CC vs. CT+TT: OR = 0.86, 95%CI = 0.67-1.10, Pheterogeneity = 0.007) , the dominantmodel (CC+CT vs. TT: OR = 0.93, 95%CI = 0.76-1.15, Pheterogeneity = 0.001) and the allele model (C vs. T: OR =0.93, 95%CI = 0.81-1.08, Pheterogeneity = 0.019). Similarly, no significant associations between TLR2+1350C>T,Arg753Gln polymorphisms and cancer risk were found. However, in the sub-group analysis of ethnicities, thetrend of pooled ORs in Asians was opposite to Caucasians. Conclusions: The present meta-analysis suggeststhat TLR2+597T>C (rs3804099), +1350C>T (rs3804100) and Arg753Gln (rs5743708) polymorphisms are notassociated with cancer risk.     

Intronic Polymorphisms of the SMAD7 Gene in Association with Colorectal Cancer

Based on genome-wide association studies (GWAS) a linkage between several variants such as single nucleotidepolymorphisms (SNPs) in intron 3 of SMAD7 (mothers against decapentaplegic homolog7) were, rs12953717,rs4464148 and rs4939827 has been noted for susceptibility to colorectal cancer (CRC). In this study we investigatedthe relationship of rs12953717 and rs4464148 with risk of CRC among 487 Iranian individuals based on a casecontrolstudy. Genotyping of SNPs was performed by PCR-RFLP and for confirming the outcomes, 10% ofgenotyping cases were sequenced with RFLP. Comparing the case and control group, we have found significantassociation between the rs4464148 SNP and lower risk of CRC. The AG genotype showed decreased risk withand odds ratio of 0.635 (adjusted OR=0.635, 95% CI: 0.417-0.967, p=0.034). There was no significant differencein the distribution of SMAD7 gene rs12953717 TT genotype between two groups of the population evaluated(adjusted OR=1.604, 95% CI: 0.978-2.633, p=0.061). On the other hand, rs12953717 T allele showed a statisticallysignificant association with CRC risk (adjusted OR=1.339, 95% CI: 1.017-1.764, p=0.037). In conclusion, wefound a significant association between CRC risk and the rs4464148 AG genotype. Furthermore, the rs12953717T allele may act as a risk factor. This association may be caused by alternative splicing of pre mRNA. Althoughwe observed a strong association with rs4464148 GG genotype in affected women, we did not detect the sameassociation in CRC male patients.     

Sequence Polymorphism in Xenobiotic Metabolising Genes in Iraqi Colorectal Cancer Patients

Objectives: Colorectal cancer (CRC) is the third most prevalent malignant neoplasm. Genetic variations in the xenobiotic metabolising cytochrome enzymes. Family 1 Subfamily A Member 1 (CYP1A1) and Family 1 Subfamily B Member 1 (CYP1B1) might play a role in cancer pathogenesis and prognosis. The aim of this work is to determine the frequency of Single Nucleotide Polymorphisms (SNPs) in CYP1A1 (rs1048943, Ile462VaI and rs4646903/MSP1) and CYP1B1 (rs1056836, Leu432Val) genes in patients with CRC cancer. It was also an attempt to identify the association between SNPs and CRC and its stage and grade at diagnosis. Methods: This case-control study was conducted in Kirkuk/Iraq, 200 patients with CRC and 200 cancer free control subjects were enrolled. Genomic DNA was extracted from venous blood samples and screened for SNPs using Restriction Fragment Length  Polymorphism (RFLP) and confirmed by the direct DNA sequencing. Results: The reference genotype of CYP1A1 gene rs1048943 is AA. Both the AG and GG variants were  significantly more frequent in the cancer group and associated with increased risks of CRC and its later stages (stages III and IV)  and poor  differentiation (p <0.01). The reference genotype of CYP1A1 rs4646903 is TT. The variant genotypes, TC and CC, had no significant association with increased odds of cancer (P>0.05) or with tumour stage or its grade (p>0.05). The GG genotype of CYP1B1 rs1056836 was the reference genotype. The CG and CC variants were not associated with increased risks of CRC (P>0.05) or its stage or grade except the CG genotype which was associated with poor differentiation (OR= 3.4, 95 % CI= 1.8 -6.5, p <0.001). Conclusion: CYP1A1 gene rs1048943 SNPs can represent a potential future marker for   CRC risk prediction and prognosis. Further evaluation in large scale studies will provide greater understanding of the effects of other genes SNPs on CRC  risk and prognosis.     

Upregulation of miR-301a correlates with poor prognosis in triple-negative breast cancer

XRCC2 is an essential part of the homologous recombination repair pathway. However, relatively little is known about the effect of XRCC2 gene C41657T and G4234C polymorphisms on the individual susceptibility to colorectal cancer (CRC). The purpose of this study was to investigate the association between XRCC2 gene C41657T and G4234C polymorphisms and CRC and to explore the relationship among the polymorphisms and clinicopathologic parameters and protein expression levels of XRCC2. A hospital-based case–control study was conducted with 246 CRC cases and 262 healthy controls. The genotypes were determined by polymerase chain reaction–restriction fragment length polymorphism. XRCC2 protein was analyzed by immunohistochemistry for the paraffin sections of 120 CRC cases. The study data showed that the C41657T genotypes were associated with the risk of CRC. The CT/TT genotypes and T allele were overrepresented among the CRC cases. Compared with CC, CT/TT enhanced the risk of CRC (odds ratio = 1.646, 95 % confidence interval = 1.127–2.404, P = 0.010). XRCC2 protein expression of CRC patients with CT/TT genotypes was significantly higher than that of the patients with CC genotype (χ ² = 4.887, P = 0.027). XRCC2 gene G4234C polymorphisms have no relevance to the risk of CRC. Our findings suggest that XRCC2 C41657T polymorphism may adjust the XRCC2 expression and might influence susceptibility of CRC.     

A new single nucleotide polymorphism in the insulin-like growth factor I regulatory region associates with colorectal cancer risk in singapore chinese.

Elevated levels of plasma insulin-like growth factor I (IGF-I) are a potential risk factor for several cancers, including colorectal cancer. Physiologic levels of plasma IGF-I vary greatly; this variation may be in part genetically determined. We identified two single nucleotide polymorphisms (SNP) in perfect linkage disequilibrium with each other and in partial linkage disequilibrium with a previously studied cytosine-adenine microsatellite [-969(CA)(n)]. We investigated one of the SNPs, -533T/C,and the 969(CA)(n) in relation to the risk of colorectal cancer in a case-control study nested within a cohort of Singapore Chinese (cases/controls = 290:873). The (CA)(21) allele, rather than the previously implicated (CA)(19) allele, was associated with a reduced risk of colorectal cancer (odds ratio for 21/21 versus all other genotypes, 0.48; 95% confidence interval, 0.28-0.84). For the -533C/T SNP, persons carrying one or more copies of the C allele had a decreased in risk of colorectal cancer compared with noncarriers (odds ratio for CC/CT versus TT, 0.58; 95% confidence interval, 0.41-0.82). This association was specific for colon, as opposed to rectal cancer and was modified by age. We also examined a functional insulin-like growth factor binding protein (IGFBP3) promoter SNP, -202 A/C, previously reported to predict serum IGFBP3 levels. Although we were able to confirm this genotype-phenotype association, the -202A/C IGFBP3 SNP was not significantly associated with colorectal cancer risk. In conclusion, we report a novel SNP in the IGF-I regulatory region that is associated with colorectal cancer risk.     

Apoptosis gene polymorphisms, age, smoking and the risk of non-small cell lung cancer

Apoptosis is important for targeting cancer cells for destruction. Various single-nucleotide polymorphisms (SNPs) in apoptotic genes have been associated with increased risks in lung cancer, particularly FAS -1377 G>A (rs2234767), FASLG -844 C>T (rs763110), IL1B +3954 C>T Phe105Phe (rs1143634) and BAT3 Ser625Pro (rs1052486). We studied the association of these SNPs with non-small cell lung cancer (NSCLC) in a large case-control study (N = 4263: 2644 cases and 1619 controls). No associations with NSCLC were observed in the main effects analysis for all four SNPs, adjusting for age, gender, smoking status, pack-years and years since smoking cessation. In subjects under age 60, for FASLG -844 C>T polymorphism, CT compared with the CC genotype, was significantly associated with increased risk of NSCLC, adjusted odds ratio (aOR) = 1.58 (1.22, 2.05), P = 0.0006 and TT aOR = 1.45 (1.01, 2.04), P = 0.04. In contrast, for those over age 60, the CT aOR = 0.91 (0.73, 1.13), P = 0.37 and TT aOR = 0.86 (0.64, 1.16), P = 0.32. The P-value for the age-genotype interaction was 0.004. For the IL1B +3954 C>T polymorphism, compared with the CC genotype, TT showed significant associations in former smokers and in men but tests of interaction were not significant (P(smoking) = 0.24, P(gender) = 0.17). No interactions were observed for FAS -1377 G>A and BAT3 Ser625Pro polymorphisms. Our findings indicate that age and smoking may modify the association of the FASLG -844 and IL1B + 3954 SNPs with the risk of NSCLC.     

Genetic Variations in the HIF1A Gene Modulate Response to Adjuvant Chemotherapy after Surgery in Patients with Colorectal Cancer

Background: Hypoxia-inducible factor 1α (HIF-1α) plays an important role in regulating cell survivaland angiogenesis, which are critical for tumor growth and metastasis. Genetic variations of HIF1A have beenshown to influence the susceptibility to many kinds of human tumors. Increased expression of HIF-1α has alsobeen demonstrated to be involved in tumor progression. However, the prognostic value of single nucleotidepolymorphisms (SNPs) inthe HIF1A gene remains to be determined in most cancer types, including colorectalcancer (CRC). In this study, we sought to investigate the predictive role of HIF1A SNPs in prognosis of CRCpatients and efficacy of chemotherapy. Materials and Methods: We genotyped two functional SNPs in HIF1Agene using the Sequenom iPLEX genotyping system and then assessed their associations with clinicopathologicalparameters and clinical outcomes of 697 CRC patients receiving radical surgery using Cox logistic regressionmodel and Kaplan Meier curves. Results: Generally, no significant association was found between these 2 SNPsand clinical outcomes of CRC. In stratified analysis of subgroup without adjuvant chemotherapy, patientscarrying CT/TT genotypes of rs2057482 exhibited a borderline significant association with better overallsurvival when compared with those carrying CC genotype [Hazard ratio (HR), 0.47; 95% confidence interval(95% CI): 0.29-0.76; P < 0.01]. Moreover, significant protective effects on CRC outcomes conferred by adjuvantchemotherapy were exclusively observed in patients carrying CC genotype of rs2057482 and in those carryingAC/CC genotype of rs2301113. Conclusions: Genetic variations in HIF1A gene may modulate the efficacy ofadjuvant chemotherapy after surgery in CRC patients.     

Genetic Variations of RAD51 and XRCC2 Genes Increase the Risk of Colorectal Cancer in Bangladeshi Population

Objectives: In case of Bangladeshi population, no report is observed till now showing the genetic variations of RAD51 (rs1801320) and XRCC2 (rs3218536) genes polymorphism having association with colorectal cancer risk. For this reason the aim of this study is to ascertain their interrelation with colorectal cancer occurrence in Bangladeshi population. Materials and Methods: A case control study was conducted where 200 colorectal cancer patients and 200 healthy volunteers were figured for this research using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). Results: Here, in case of RAD51 (rs1801320), G/C heterozygous genotype was found significant (p=0.037; OR=1.64; 95% CI=1.03 to 2.6). On the other hand, G/G genotype was not found statistically significant (p=0.423; OR=1.61; 95% CI=0.49 to 5.22) and significance was observed for GC+GG (p=0.030; OR=1.63; 95% CI=1.05 to 2.55). In case of XRCC2 (rs3218536), C/T heterozygous genotype was remarked statistically significant (p=0.033; OR=1.60; 95% CI=1.04 to 2.46). The T/T genotype was not recorded statistically significant (p=0.237; OR=1.65; 95% CI=0.72 to 3.76) but significance found for CT+TT (p=0.027; OR=1.61; 95% CI=1.05 to 2.45). Moreover, it is found that the risk factor of developing CRC is observed in G/C, C/T heterozygote and GC+GG, CT+TT (heterozygote+ mutant) in RAD51 (rs1801320) and XRCC2 (rs3218536) respectively although no significance is observed in case of G/G and T/T mutant. Conclusions: So, the association of RAD51 (rs1801320) and XRCC2 (rs3218536) genes polymorphism with colorectal cancer risk is observed in Bangladeshi population.     

Association Analysis of Single Nucleotide Polymorphisms in miR-146a and miR-196a2 on the Prevalence of Cancer in Elderly Japanese: A Case-Control Study

Background: Single nucleotide polymorphisms (SNPs) affecting microRNA (miR) sequences may influencecarcinogenesis. Our current study primarily aimed to confirm previously conducted association studies betweenrs2910164 found on miR-146a, and rs11614913 located on miR-196a2 polymorphisms and cancer phenotypesin the Japanese elderly population. rs2910164 (G/C) and rs11614913 (T/C) polymorphisms were determined bygenotyping on the samples collected from 1,351 consecutive autopsy cases registered in the Japanese SNPs forgeriatric research (JG-SNP) data base. Cancer samples were systematically reviewed, pathologically verified andassessed with respect to miR-146a and miR-196a2 genotypic variation. The current study covered 726 males and625 females with a mean age of 80.3±8.9 years. The study included 524 subjects without cancer and 827 subjectswith at least one type of cancer, such as gastric (n=160), lung (n=148), colorectal (n=116) or others. Males withcancers (n=467) were more numerous than females (n=360). Both rs11614913 (CT: TT adjusted odds ratio (OR)95% confidence interval (95%CI)=0.98 (0.75-1.28), p=0.873, CC: TT adjusted OR (95%CI)=1.06 (0.76-1.47),p=0.737, CT+CC: TT, adjusted OR (95%CI)=0.99 (0.77-1.29), p=0.990), and rs2910164 (CG: CC adjusted OR(95%CI)=1.12 (0.87-1.44), p=0.383, GG: CC adjusted OR (95%CI)=1.03 (0.71-1.48), p=0.887, CG+GG: CCadjusted OR (95%CI)=1.10 (0.87-1.39), p=0.446) polymorphisms did not show significant association with overallcancer in all subjects. However, “CC” genotype in rs11614913 polymorphism was significantly associated withincreased gastric cancer (n=160) in all subjects (CC: CT+TT, adjusted OR (95%CI)=1.50 (1.02-2.22), p=0.040).We found that rs11614913 and rs2910164 do not pose general cancer risk, but rs11614913 may influence gastriccancer in Japanese elderly population. Confirmation of our study results requires further investigations withlarger subject populations.     

Quantitative assessment of the association between MTHFR C677T polymorphism and colorectal cancer risk in East Asians

A great number of studies regarding the association between MTHFR C677T polymorphism and risk of colorectal cancer (CRC) in East Asians were published, but the results were inconsistent. Thus, a meta-analysis was performed to investigate the association. PubMed, Embase, and CBM databases were searched for eligible publications. Pooled odds ratios (ORs) with 95?% confidence intervals (95?% CIs) were calculated using random or fixed effect models. Finally, 24 case?Ccontrol studies with a total of 7,230 CRC cases and 9,285 controls were included. Meta-analyses of a total of 24 studies showed there was a statistically significant association between MTHFR C677T polymorphism and decreased CRC risk in East Asians under four genetic models (T versus C, OR?=?0.92, 95?% CI 0.85?C0.99; TT versus CC, OR?=?0.80, 95?% CI 0.69?C0.94; TT versus CT/CC, OR?=?0.82, 95?% CI 0.71?C0.95; TT/CT versus CC, OR?=?0.92, 95?% CI 0.86?C0.98). The cumulative meta-analyses for the allele contrast (T versus C), homozygote (TT versus CC), dominant (TT/CT versus CC), and recessive (TT versus CT/CC) models all showed a trend of more obvious association as information accumulated by year. Subgroup analyses by country further identified this association in Korea and Japan. This meta-analysis suggests that MTHFR C677T polymorphism is associated with decreased risk of colorectal cancer in East Asians, and MTHFR 677T variant has a protective effect on colorectal cancer.