• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7467-7472
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• 2013

Background: Polymorphisms of genes encoding cytokines could be potential biomarkers to predict risk of gastric cancer (GC). Here, we investigated the association between the IL-6 -6331 (T/C, rs10499563) polymorphism in its promoter region and GC risk. Methods: In this case-control study of 215 GC cases and 518 non-cancer controls, the IL-6 -6331 (T/C, rs10499563) polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: Individuals with the TC or CC genotype were associated with a significantly decreased risk of GC (OR=0.710, 95%CI: 0.504-0.999, P=0.049) compared with TT wild-type carriers. Ther C allele was also associated with significantly decreased risk of GC (OR=0.715, 95%CI: 0.536-0.954, P=0.023) compared with the T allele. In the stratification analysis, TC or CC genotypes were associated with significantly decreased GC risk in subgroups of males, people older than 60, and H. pylori-positive cases. However, no significant interaction was observed for TC or CC genotypes with H. pylori infection. On stratification with the Lauren classification, TC or CC genotypes were associated with significantly decreased risk of diffuse-type GC (OR=0.497, 95%CI: 0.266-0.925, P=0.027), also in subgroups of males, people older than 60, and H. pylori-positive cases. Conclusions: The IL-6 -6331 (T/C, rs10499563) polymorphism is associated with genetic susceptibility of GC and may have the potential to predict GC risk.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3335-3340
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• 2016

Background: Oral submucous fibrosis (OSF) is a precancerous condition with a 4 to13% malignant transformation rate. Related to the habit of areca nut chewing it is mainly prevalent in South-east Asian countries where the habit of betel quid chewing is frequently practised. On chewing, alkaloids and polyphenols are released which undergo nitrosation and give rise to N-nitrosamines which are cytotoxic agents. CYP450 is a microsomal enzyme group which metabolizes various endogenous and exogenous chemicals including those released by areca nut chewing. CYP1A1 plays a central role in metabolic activation of these xenobiotics, whereas CYP2E1 metabolizes nitrosamines and tannins. Polymorphisms in genes that code for these enzymes may alter their expression or function and may therefore affect an individuals susceptibility regarding OSF and oral cancer. The present study was therefore undertaken to investigate the association of polymorphisms in CYP1A1 m2 and CYP2E1 (RsaI/PstI) sites with risk of OSF among areca nut chewers in the Northern India population. A total of 95 histopathologically confirmed cases of OSF with history of areca nut chewing not less than 1 year and 80, age and sex matched controls without any clinical signs and symptoms of OSF with areca nut chewing habit not less than 1 year were enrolled. DNA was extracted from peripheral blood samples and polymorphisms were analyzed by PCR-RFLP method. Gene polymorphism of CYP1A1 at NcoI site was observed to be significantly higher (p = 0.016) in cases of OSF when compared to controls. Association of CYP1A1 gene polymorphism at NcoI site and the risk of OSF (Odd's Ratio = 2.275) was also observed to be significant. However, no such association was observed for the CYP2E1 gene polymorphism (Odd's Ratio = 0.815). Our results suggest that the CYP1A1 gene polymorphism at the NcoI site confers an increased risk for OSF.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6025-6030
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• 2013

Background: Matrix metalloproteinase-2 (MMP-2) is an enzyme with proteolytic activity against matrix proteins, particularly basement membrane constituents. A single nucleotide polymorphism (SNP) at -1306, which disrupts a Sp1-type promoter site (CCACC box), results in strikingly lower promoter activity with the T allele. In the present study, we investigated whether this MMP-2 genetic polymorphism might be associated with susceptibility to colorectal cancer (CRC) in the Saudi population. We also analyzed MMP-2 gene expression level sin CRC patients and 4 different cancer cell lines. Materials and Methods: TaqMan allele discrimination assays and DNA sequencing techniques were used to investigate the $C^{-1306}T$ SNP in the MMP-2 gene of Saudi colorectal cancer patients and controls. The MMP-2 gene expression level was also determined in 12 colon cancer tissue samples collected from unrelated patients and histologically normal tissues distant from tumor margins. Results and Conclusions: The MMP-2 $C^{-1306}T$ SNP in the promoter region was associated with CRC in our Saudi population and the MMP-2 gene expression level was found to be 10 times higher in CRC patients. The MMP-2 $C^{-1306}T$ SNP is significantly associated with CRC in the Saudi population and this finding suggested that MMP-2 variants might help predict CRC progression risk among Saudis. We propose that analysis of this gene polymorphism could assist in identification of patient subgroups at risk of a poor disease outcome.

• Genomics & Informatics
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• v.10 no.3
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• pp.167-174
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• 2012

AKT is a signal transduction protein that plays a central role in the tumorigenesis. There are 3 mammalian isoforms of this serine/threonine protein kinase-AKT1, AKT2, and AKT3-showing a broad tissue distribution. We first discovered 2 novel polymorphisms (AKT2 -9826 C/G and AKT3 -811 A/G), and we confirmed 6 known polymorphisms (AKT2 -9473 C/T, AKT2 -9151 C/T, AKT2 -9025 C/T, AKT2 -8618G/A, AKT3 -675 A/-, and AKT3 -244 C/T) of the AKT2 and AKT3 promoter region in 24 blood samples of Korean lung cancer patients using direct sequencing. To evaluate the role of AKT2 and AKT3 polymorphisms in the risk of Korean lung cancer, genotypes of the AKT2 and AKT3 polymorphisms (AKT2 -9826 C/G, AKT2 -9473 C/T, AKT2 -9151 C/T, AKT2 -9025 C/T, AKT2 -8618G/A, and AKT3 -675 A/-) were determined in 360 lung cancer patients and 360 normal controls. Statistical analyses revealed that the genotypes and haplotypes in the AKT2 and AKT3 promoter regions were not significantly associated with the risk of lung cancer in the Korean population. These results suggest that polymorphisms of the AKT2 and AKT3 promoter regions do not contribute to the genetic susceptibility to lung cancer in the Korean population.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.189-193
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• 2013

Many epidemiological studies in Asian populations have investigated associations between the Arg399Gln gene polymorphism of X-ray repair cross complementing gene 1 (XRCC1) and risk of cervical carcinoma, but no conclusions have been available because of controversial results. Therefore a meta-analysis was conducted for clarification. Relevant studies were identified by searching the Pubmed, Embase, the Web of Science, Cochrane Collaboration's database, Chinese National Knowledge Infrastructure (CNKI), Wanfang database and China Biological Medicinse (CBM) until September, 2012. A total of eight studies were included in the present meta-analysis, which described 1,759 cervical carcinoma cases and 2,497 controls. Odds ratios (ORs) and corresponding 95% confidence intervals (95%CIs) as effect size were calculated by fixed-effect or random-effect models. The overall results indicated that the XRCC1-399G/A polymorphism was marginally associated with cervical carcinoma in Asians: OR (95%CI): 1.16 (1.07, 1.26) in the G/A vs G/G inheritance model, 1.24 (0.87, 1.76)in A/A vs G/G inheritance model, 1.13 (1.01, 1.27) in the dominant inheritance model and 1.18 (0.94, 1.47) in the recessive inheritance model. Subgroup analyses on sample size showed no significant correlation in the small-sample size group but the large-sample size group was consistent with the outcomes of overall meta-analysis. In the subgroup analysis by regions, we only found significant association under the G/A vs G/G inheritance model in the Chinese population. For the non-Chinese populations, no correlation was detected in any genetic inheritance model. In the Asian populations, XRCC1-399G/A gene polymorphism was implied to be associated with cervical carcinoma.

• Tuberculosis and Respiratory Diseases
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• v.71 no.4
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• pp.254-258
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• 2011

Background: Although the aging process and features of chronic obstructive pulmonary disease (COPD) have several similarities, the relationship between aging and COPD pathogenesis remains incompletely understood. The klotho gene was found to be related to premature aging and emphysematous changes in an animal model. We investigated whether klotho gene polymorphisms are related to COPD susceptibility and emphysema severity. Methods: A total of 219 COPD subjects from the Korean Obstructive Lung Disease Cohort and 305 control subjects were genotyped for two single nucleotide polymorphisms (SNPs) of the klotho gene associated with coronary artery disease. Logistic regression was performed to determine the association of these SNPs with COPD susceptibility and linear regression was performed to investigate their association with emphysema severity in COPD subjects. Results: The mean age of the COPD subjects was 66 years and their mean FEV1 was 1.46 L. There were no associations between either SNP or COPD susceptibility (p=0.6 and 0.2, respectively) and there were no associations with emphysema severity. Conclusion: Genetic polymorphisms of the klotho gene were not associated with COPD in a Korean population.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.387-393
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• 2016

Background: CYP1A1 is a candidate gene for low-penetrance breast cancer susceptibility, as it plays an important role in the metabolism of carcinogens and estrogens. Purpose: The objective of this study was to assess the association between M2 (A2455G, Ile462Val) and M4 (C2453A, Thr461Asn) polymorphisms in CYP1A1 and breast cancer risk among Jordanian women and in subgroups stratified by menopausal status and smoking history. Materials and Methods: Blood samples were collected from 112 breast cancer female patients and 115 age-matched controls who underwent breast cancer screening with imaging and showed negative results (BI-RADS I or BI-RADS II). Genotyping was performed using the PCR-RFLP technique. Results: No statistically significant overall association was found between breast cancer risk and CYP1A1 M2 genotypes (p= 0.55; OR = 0.77; 95% CI= 0.32 - 1.83) nor with the M4 polymorphism (p= 0.95; OR= 0.95; 95% CI= 0.51 - 1.88). Analysis of subgroups defined by menopausal status or smoking history also revealed no association with these polymorphisms. Furthermore, the four identified haplotypes (AC; AA; GC and GA) were equally distributed among cases and controls, and haplotype analysis showed a strong linkage disequilibrium of both studied loci in either cases or controls (D'=1). Conclusions: Based on the study results, CYP1A1 M2 and M4 polymorphisms do not seem to play a major role in breast cancer risk among Jordanian females.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1939-1944
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• 2015

MicroRNA-27a (miR-27a) is deemed to be an oncogene that plays an important role in development of various cancers, and single nucleotide polymorphism (SNP) of miR-27a can influence the maturation or aberrant expression of hsa-miR27a, resulting in increased risk of cancer and poor prognosis for non-small cell lung cancer (NSCLC). This study aimed to assess the effects of rs895819 within miR-27a on susceptibility and prognosis of NSCLC patients in 560 clinical confirmed cases and 568 healthy check-up individuals. Adjusted odds/hazard ratios (ORs/HRs) and 95% confidential intervals (CIs) were calculated to evaluate the association between rs895819 and the risk and prognosis of NSCLC. The results showed that allele A and genotype GG of rs895819 were significantly associated with an increased risk of NSCLC (38.9% vs 30.8%, adjusted OR=1.26, 95%CI=1.23-1.29 for allele G vs A; 18.1% vs 11.7%, adjusted OR=1.67, 95%CI=1.59-1.75 for genotype GG vs AA). Moreover, positive associations were also observed in dominant and recessive models (53.7% vs 49.9%, adjusted OR=1.17, 95%CI=1.13-1.20 for GG/AG vs AA; 18.1% vs 11.7%, adjusted=1.65, 95%CI=1.58-1.73). However, no significant association was found between rs895819 and the prognosis of NSCLC in genotype, dominant and recessive models. These results suggested that miR-27a might be involved in NSCLC carcinogenesis, but not in progression of NSCLC. The allele G, genotype GG and allele G carrier (GG/AG vs AA) of rs895819 might be genetic susceptible factors for NSCLC. Further multi-central, large sample size and well-designed prospective studies as well as functional studies are warranted to verify our findings.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.11
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• pp.4727-4732
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• 2015

Background: Folylpolyglutamate synthetase (FPGS), an important enzyme in the folate metabolic pathway, plays a central role in intracellular accumulation of folate and antifolate in several mammalian cell types. Loss of FPGS activity results in decreased cellular levels of antifolates and consequently to polyglutamatable antifolates in acute lymphoblastic leukemia (ALL). Materials and Methods: During May 1997 and December 2003, 134 children diagnosed with ALL were recruited from one hospital in Thailand. We performed a mutation analysis in the coding regions of the FPGS gene and the association between single nucleotide polymorphisms (SNPs) within FPGS in a case-control sample of childhood ALL patients. Mutation screening was conducted by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and subsequently with direct sequencing (n=72). Association analysis between common FPGS variants and ALL risk was done in 98 childhood ALL cases and 95 healthy volunteers recruited as controls. Results: Seven SNPs in the FPGS coding region were identified by mutation analysis, 3 of which (IVS13+55C>T, g.1297T>G, and g.1508C>T) were recognized as novel SNPs. Association analysis revealed 3 of 6 SNPs to confer significant increase in ALL risk these being rs7039798 (p=0.014, OR=2.14), rs1544105 (p=0.010, OR= 2.24), and rs10106 (p=0.026, OR=1.99). Conclusions: These findings suggested that common genetic polymorphisms in the FPGS coding region including rs7039789, rs1544105, and rs10106 are significantly associated with increased ALL risk in Thai children.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2809-2813
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• 2014

Background: This study was conducted to investigate the association between single nucleotide polymorphisms (SNPs) in telomerase reverse transcriptase (TERT) and cleft lip and palate transmembrane1-like (CLPTM1L) and lung cancer risk in a Chinese population. Methods: We performed a hospital-based case-control study, including 980 lung cancer cases and 1000 cancer-free controls matched for age and sex. Each case and control was interviewed to collect information by well-trained interviewers. A total of 5 ml of venous blood was collected for genotype testing of TERT rs2736098 and CLPTM1L rs401681 using TaqMan methodology. Results: The results revealed that the variant homozygote TERT rs2736098TT was associated with an increased risk of lung cancer (OR=2.017, 95%CI=1.518-2.681), especially lung adenocarcinoma (OR=2.117, 95%CI=1.557-3.043) and small cell carcinoma (OR=1.979, 95%CI: 1.174-3.334), compared with the TERT rs2736098CC genotype. Similar results were observed in non-smokers. Conclusion: The TERT rs2736098 polymorphism might affect the susceptibility to lung cancer in Chinese populations. The associations need to be verified in larger and different populations.