• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8815-8822
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• 2014

Background: The incidence of stomach cancer in India is highest in the state of Mizoram. In this population based matched case-control study, we evaluated the relationship between CYP450 2E1 RsaI polymorphism and risk of stomach cancer taking into considering various important dietary habits along with tobacco, alcohol consumption and H. pylori infection status. Materials and Methods: A total of 105 histologically confirmed stomach cancer cases and 210 matched healthy population controls were recruited. CYP2E1 RsaI genotypes were determined by PCR-RFLP and H. pylori infection status by ELISA. Information on various dietary, tobacco and alcohol habits was recorded in a standard questionnaire. Results: Our study revealed no significant association between the CYP2E1 RsaI polymorphism and overall risk of stomach cancer in Mizoram. However, we observed a non-significant protective effect of the variant allele (A) of CYP2E1 against stomach cancer. Tobacco smokers carrying C/C genotype have three times more risk of stomach cancer, as compared to non-smokers carrying C/C genotype. Both Meiziol and cigarette current and past smokers who smoked for more than 10 times per day and carrying the (C/C) genotype are more prone to develop stomach cancer. Smoke dried fish and preserved meat (smoked/sun dried) consumers carrying C/C genotype possesses higher risk of stomach cancer. No significant association between H. pylori infection and CYP2E1 RsaI polymorphism in terms of stomach cancer was observed. Conclusions: Although no direct association between the CYP2E1 RsaI polymorphism and stomach cancer was observed, relations with different tobacco and dietary risk habits in terms of developing stomach cancer exist in this high risk population of north-eastern part of India. Further in-depth study recruiting larger population is required to shed more light on this important problem.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2153-2158
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• 2014

Beclin 1 is a key factor for initiation and regulation of autophagy, which is a cellular catabolic process involved in tumorigenesis. To investigate the role of alternative splicing of Beclin1 in the regulation of autophagy in leukemia cells, Beclin1 mRNA from 6 different types of cell lines and peripheral blood mononuclear cells from 2 healthy volunteers was reversely transcribed, subcloned, and screened for alternative splicing. New transcript variants were analyzed by DNA sequencing. A transcript variant of Beclin 1 gene carrying a deletion of exon 11, which encoded a C-terminal truncation of Beclin 1 isoform, was found. The alternative isoform was assessed by bioinformatics, immunoblotting and subcellular localization. The results showed that this variable transcript is generated by alternative 3' splicing, and its translational product displayed a reduced activity in induction of autophagy by starvation, indicating that the spliced isoform might function as a dominant negative modulator of autophagy. Our findings suggest that the alternative splicing of Beclin 1 might play important roles in leukemogenesis regulated by autophagy.

• Asian-Australasian Journal of Animal Sciences
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• 제33권11호
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• pp.1725-1731
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• 2020

Objective: An initial RNA-Sequencing study revealed that UDP-galactose-4-epimerase (GALE) was one of the most promising candidates for milk protein concentration in Chinese Holstein cattle. This enzyme catalyzes the interconversion of UDP-galactose and UDP-glucose, an important step in galactose catabolism. To further validate the genetic effect of GALE on milk protein traits, genetic variations were identified, and genotypes-phenotypes associations were performed. Methods: The entire coding region and the 5'-regulatory region (5'-UTR) of GALE were re-sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed linear animal model with a population encompassing 1,027 Chinese Holstein cows. Results: A total of three variants in GALE were identified, including two novel variants (g.2114 A>G and g.2037 G>A) in the 5'-UTR and one previously reported variant (g.3836 G>C) in an intron. All three single nucleotide polymorphisms (SNPs) were associated with milk yield (p<0.0001), fat yield (p = 0.0006 to <0.0001), protein yield (p = 0.0232 to <0.0001) and protein percentage (p<0.0001), while no significant associations were detected between the SNPs and fat percentage. A strong linkage disequilibrium (D' = 0.96 to 1.00) was observed among all three SNPs, and a 5 Kb haplotype block involving three main haplotypes with GAG, AGC, and AGG was formed. The results of haplotype association analyses were consistent with the results of single locus association analysis (p<0.0001). The phenotypic variance ratio above 3.00% was observed for milk protein yield that was explained by SNP-g.3836G >C. Conclusion: Overall, our findings provided new insights into the polymorphic variations in bovine GALE gene and their associations with milk protein concentration. The data indicate their potential uses for marker-assisted breeding or genetic selection schemes.

• Asian Pacific Journal of Cancer Prevention
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• 제16권10호
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• pp.4215-4218
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• 2015

Gastric cancer (GC) is one of the most common malignancies in the world. It is the first cause of cancer deaths in both sexes In Iranian population. Circulating insulin-like growth factor-one (IGF-1) levels have been associated for gastric cancer. IGF-1 protein has central roles involved in the regulation of epithelial cell growth, proliferation, transformation, apoptosis and metastasis. Single nucleotide polymorphism in IGF-1 regulatory elements may lead to alter in IGF-1expression level and GC susceptibility. The aim of this study was to investigate the influence of IGF-1 gene polymorphism (rs5742612) on risk of GC and clinicopathological features for the first time in Iranian population. In total, 241 subjects including 100 patients with GC and 141 healthy controls were recruited in our study. Genotypes were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay with DNA from peripheral blood. The polymorphism was statistically analyzed to investigate the relationship with the risk of GC and clinicopathological properties. Logistic regression analysis revealed that there was no significant association between rs5742612 and the risk of GC. In addition, no significant association between genotypes and clinicopathological features was observed (p value>0.05). The frequencies of the CC, CT, and TT genotypes were 97%, 3%, and 0%, respectively, among the cases, and 97.9%, 2.1%, and 0%, respectively, among the controls. CC genotype was more frequent in cases and controls. The frequencies of C and T alleles were 98.9% and 1.1% in controls and 98.5% and 1.5% in patient respectively. Our results provide the first evidence that this variant is rare in Iranian population and it may not be a powerful genetic predisposing biomarker for prediction GC clinicopathological features in an Iranian population.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.901-907
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• 2012

Objective: Cumulative evidence suggests that MLH1, the key component in the mismatch pathway, plays an important role in human cancers. Two potential functional polymorphisms (-93G>A and I219V) of MLH1 have been implicated in cancer risk. The aim of this meta-analysis was to summarize the evidence for associations. Methods: Eligible studies were identified by searching the electronic literature PubMed, ScienceDirect and Embase databases for relevant reports and bibliographies. Studies were included if of case-control design investigating MLH1 polymorphisms (-93G>A and I219V) and cancer risk with sufficient raw data for analysis. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to evaluate the strength of associations. Results: Our meta-analysis from 33 published case-control studies showed the variant A allele of -93G>A polymorphism to be associated with increased risk in all genetic models (AA vs. GG: OR = 1.22, 95% CI: 1.03-1.44), especially among non-Asians (AA vs. GG: OR = 1.28, 95% CI: 1.04-1.58). For the I219V polymorphism, however, there was no main effect associated with overall cancer risk in any genetic model. Conclusions: The meta-analysis suggested that the MLH1 -93G>A polymorphism may be a biomarker of cancer susceptibility. Large sample association studies and assessment of gene-to-gene as well as gene-to-environment interactions are required to confirm these findings.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.837-846
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• 2012

Breast cancer (BCa) is the leading type of cancer in Mexican women. Genetic factors, such as single nucleotide polymorphisms (SNP) of P450 system, have been reported in BCa. In this report, and for the first time in the literature, we analyzed the rs3735684 (7021 G>A), rs11553651 (15016 G>T) and rs56195291 (60020 C>G) polymorphisms in the CYP2W1, 4F11 and 8A1 genes in patients with BCa and in healthy Mexican women to identify a potential association between these polymorphisms and BCa risk. Patients and controls were used for polymorphism analysis using an allelic discrimination assay with TaqMan probes and confirmed by DNA sequencing. Links with clinic-pathological characteristics were also analyzed. Statistical analysis was performed using the standard ${\chi}^2$ or Fisher exact test statistic. No significant differences were observed in the distributions of CYP2W1 (OR 8.6, 95%CI 0.43-172.5 P>0.05; OR 2.0, 95%CI 0.76-5.4, P>0.05) and CYP4F11 (OR 0.3, 95%CI 0.01-8.4 P>0.05) genotypes between the patients and controls. Only the CYP8A1 CC genotype was detected in patients with BCa and the controls. All polymorphism frequencies were in Hardy-Weinberg Equilibrium (HWE) in the controls (P>0.05). We found a significant association between BCa risk and smoking, use of oral contraceptives or hormonal replacement therapy (HRT), obesity, hyperglycemia, chronic diseases, family history of cancer and menopausal status in the population studied (P<0.05). Tobacco, oral contraceptive or HRT, chronic diseases and obesity or overweight were strongly associated with almost eight, thirty-five, nine and five-fold increased risk for BCa. Tobaco, obesity and hyperglycemia significantly increased the risk of BCa in the patients carrying variant genotypes of CYP2W1 (P<0.05). These results indicate that the CYP2W1 rs3735684, CYP4F11 rs11553651 and CYP8A1 rs56195291 SNPs are not a key risk factor for BCa in Mexican women. This study did not detect an association between the CYP2W1, 4F11 and 8A1 genes polymorphisms and BCa risk in a Mexican population. However, some clinico-pathological risk factors interact with CYP2W1 genotypes and modifies susceptibility to BCa.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.851-856
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• 2012

Objective: NBS1 plays a key role in the repair of DNA double-strand break (DSB). We conducted this study to investigate the effect of two critical polymorphisms (rs1805794 and rs13312840) in NBS1 on treatment response and prognosis of advanced non-small cell lung cancer (NSCLC) patients with platinum-based chemotherapy. Methods: Using TaqMan methods, we genotyped the two polymorphisms in 147 NSCLC patients. Odds ratios (ORs) and their 95% confidential intervals (CIs) were calculated as a measure of difference in the response rate of platinum-based chemotherapy using logistic regression analysis. The Kaplan-Meier and log-rank tests were used to assess the differences in progression-free survival (PFS) and overall survival (OS). Cox proportional hazards model was applied to assess the hazard ratios (HRs) for PFS and OS. Results: Neither of the two polymorphisms was significantly associated with treatment response of platinum-based chemotherapy. However, patients carrying the rs1805794 CC variant genotype had a significantly improved PFS compared to those with GG genotype (16.0 vs. 8.0 months, P = 0.040). Multivariable cox regression analysis further showed that rs1805974 was a significantly favorable prognostic factor for PFS [CC/CG vs. GG: Adjusted HR = 0.62, 95% CI: 0.39-0.99; CC vs. CG/GG: Adjusted HR = 0.56, 95% CI: 0.32-0.97). Similarly, rs13312840 with a small sample size also showed a significant association with PFS (CC vs. CT/TT: Adjusted HR = 25.62, 95% CI: 1.53-428.39). Conclusions: Our findings suggest that NBS1 polymorphisms may be genetic biomarkers for NSCLC prognosis especially PFS with platinum-based chemotherapy in the Chinese population.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.1047-1055
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• 2014

Background: MicroRNAs (miRNAs) are an abundant class of endogenous small non-coding RNAs of 20-25 nucleotides in length that function as negative gene regulators. MiRNAs play roles in most biological processes, as well as diverse human diseases including cancer. Recently, many studies investigated the association between SNPs in miR-146a rs2910164, miR-196a2 rs11614913, miR-149 rs229283, miR-499 rs3746444 and colorectal cancer (CRC), which results have been inconclusive. Methodology/Principal Findings: PubMed, EMBASE, CNKI databases were searched with the last search updated on November 5, 2013. For miR-196a2 rs11614913, a significantly decreased risk of CRC development was observed under three genetic models (dominant model: OR = 0.848, 95%CI: 0.735-0.979, P = 0.025; recessive model: OR = 0.838, 95%CI: 0.721-0.974, P = 0.021; homozygous model: OR = 0.754, 95%CI: 0.627-0.907, P = 0.003). In the subgroup analyses, miR-$196a2^*T$ variant was associated with a significantly decreased susceptibility of CRC (allele model: OR = 0.839, 95%CI: 0.749-0.940, P = 0.000; dominant model: OR = 0.770, 95%CI: 0.653-0.980, P = 0.002; recessive model: OR = 0.802, 95%CI: 0.685-0.939, P = 0.006; homozygous model: OR = 0.695, 95%CI: 0.570-0.847, P = 0.000). As for miR-149 rs2292832, the two genetic models (recessive model: OR = 1.199, 95% CI 1.028-1.398, P = 0.021; heterozygous model: OR = 1.226, 95% CI 1.039-1.447, P = 0.013) demonstrated increased susceptibility to CRC. On subgroup analysis, significantly increased susceptibility of CRC was found in the genetic models (recessive model: OR = 1.180, 95% CI 1.008-1.382, P = 0.040; heterozygous model: OR = 1.202, 95% CI 1.013-1.425, P = 0.013) in the Asian group. Conclusions: These findings supported that the miR-196a2 rs11614913 and miR-149 rs2292832 polymorphisms may contribute to susceptibility to CRC.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.957-961
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• 2014

Purpose: With regard to the protective effect of vitamin D against colorectal cancer (CRC), we evaluated genetic variants that might influence vitamin D metabolism: vitamin D receptor (VDR), vitamin D binding protein (GC), vitamin D 25-hydroxylase (CYP2R1), and vitamin D 25-hydroxy 1-alpha hydroxylase (CYP27B1). Materials and Methods: A total of 657 subjects, including 303 cases with CRC and 354 controls were enrolled in this case-control study. All 657 were genotyped for the four gene variants using PCR-RFLP methods. Results: In this study, no significant difference was observed for VDR (rs2238136), GC (rs4588), CYP2R1 (rs12794714), and CYP27B1 (rs3782130) gene variants in either genotype or allele frequencies between the cases with CRC and the controls and this lack of difference remained even after adjustment for age, BMI, sex, smoking status, NSAID use, and family history of CRC. Furthermore, no evidence for effect modification of the variants and CRC by BMI, sex, or tumor site was observed. Conclusions: Our findings do not support a role for VDR, GC, and CYP27B1 genes in CRC risk in our Iranian population. Another interesting finding, which to our knowledge has not been reported previously, was the lack of association with the CYP2R1 gene polymorphism. Nonetheless, our findings require confirmation and possible roles of vitamin D metabolism-related genes in carcinogenesis need to be further investigated.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2937-2943
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• 2013

Backgrounds: Polymorphisms of OPRM1 A118G and ABCB1 C3435T have been suggested to contribute to inter-individual variability regarding pain sensitivity, opioid usage, tolerance and dependence and incidence of adverse effects in patients with chronic pain. This study aimed to investigate the association of both two polymorphisms with opioid requirements in Chinese patients with cancer pain. Methods: The genotypes of rs1799971 (OPRM1) and rs1045642 (ABCB1) were determined by PCR-RFLP and direct sequencing methods respectively in 112 patients with cancer-related pain. Comparisons between the different genotype or allele groups were performed with t-tests or one-way ANOVA tests, as appropriate. The potential relationship of allele number with opioid response was performed with a trend Jonckheere-Terpstra test. Results: In the 112 subjects, the frequencies of variant 118 G and 3435T allele were 38.4% and 37.9%, respectively. Significant higher 24h-opioid doses were observed in patients with GG (P=0.0004) and AG + GG (P=0.005) genotypes than the AA carriers. The dominant mutant 118G allele tended to be associated with progressively increasing 24h-opioiddoses (P=0.001). Compared with CC/CT, patients with ABCB1 TT genotype received higher 24h- and weight-surface area-adjusted-24h- opioids doses (P=0.057 and 0.028, respectively). Conclusions: The OPRM1 A118G single nucleotide polymorphism (SNP) is a key contributor for the inter-individual variability in opioidrequirements in Chinese cancer pain patients. This may possibly extend to the ABCB1 C3435T SNP.