Genetic polymorphism of epidermal growth factor 61A>G and cancer risk: A meta-analysis

Background: Numerous studies have investigated the risk of cancer associated with the polymorphism of epidermal growth factor (EGF) 61A>G, but the results have been inconsistent. We performed this meta-analysis to drive a more precise estimation of association between this polymorphism and risk of cancer. Methods: Electronic searches of PubMed and EMBASE were conducted to select studies. Case-control studies containing available genotype frequencies of EGF 61A>G were chose, and Odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of this association. Results: 23 case-control studies including 5578 cases and 7306 controls were identified. This meta-analysis showed significant effect of EGF 61A>G on cancer risk (GG vs. AA: OR = 1.34, 95%CI = 1.05–1.72; GG vs. GA + AA: OR = 1.23, 95%CI = 1.03–1.47; GG + GA vs. AA: OR = 1.18, 95%CI = 1.02–1.38). In subgroup analysis, significant increased risk was found in gastric cancer and glioma in additive model (OR = 1.54, 95%CI = 1.13–2.12; OR = 1.69, 95%CI = 1.21–2.37) and in recessive model (OR = 1.29, 95%CI = 1.10–1.52; OR = 1.54, 95%CI = 1.16–2.04). Conclusion: This meta-analysis suggested that the EGF 61G allele is a risk factor of cancer, especially for gastric cancer and glioma.     

Paraoxonase 1 genetic polymorphisms and susceptibility to breast cancer: a meta-analysis

AimThe paraoxonase 1 gene (PON1, MIN: 168820) is a member of the multifactorial antioxidant enzyme paraoxonase family (EC 3.1.1.2). Two common functional single-nucleotide polymorphisms L55M (dbSNP: rs854560) and Q192R (dbSNP: rs662) have been identified in the coding region of PON1. Several studies have investigated the associations between polymorphisms of PON1 and susceptibility to breast cancer, but have yielded apparently conflicting results. We therefore carried out a meta-analysis of published studies to clarify this inconsistency and to establish a comprehensive picture of the relationship between PON1 gene variants and breast cancer risk. Method: Overall six eligible studies were identified. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using fixed and random-effect models. Results: In our meta-analysis, the presence of the R allele was associated with decreased risk of breast cancer (QR + RR compared to QQ genotype, summary OR = 0.57, 95% CI: 0.49–0.67, P < 0.001). Both heterozygosity (OR = 1.32, 95% CI: 1.10–1.58, P = 0.002) and homozygosity (OR = 2.16, 95% CI: 1.75–2.68, P < 0.001) for the 55M allele were associated with increased risk of breast cancer. Also there was a significant linear trend in risk associated with zero, one, and two 55M alleles (χ² = 54.2, P < 0.001).ConclusionThe present study showed that PON1 M and Q alleles are associated with a higher risk of breast cancer. Individuals having MM and QQ genotypes have a lower level and lower detoxification activity of the PON1 enzyme, which may increase the vulnerability of the breast to genetic damage by reducing the ability to detoxify inflammatory oxidants, as well as dietary carcinogens.     

STK15 rs2273535 polymorphism and cancer risk: A meta-analysis of 74,896 subjects

Background: It has been suggested that the serine/threonine kinase 15 (STK15) T91A rs2273535 polymorphism is associated with susceptibility to cancer. However, the results are conflicting. We performed this meta-analysis to derive a more precise estimation of the relationship. Methods: PubMed was searched to select studies. Case–control studies containing available genotype frequencies of the STK15 rs2273535 polymorphism were chosen, and the odds ratio (OR) with its 95% confidence interval (CI) was utilized to assess the strength of association. Results: 52 studies – including 34,057 cases and 40,839 controls – were identified. A significant effect of the STK15 rs2273535 polymorphism on cancer risk was found (AA vs. TT: OR = 1.13, 95%CI = 1.01–1.26, P_{heterogeneity} < 0.001; AA vs. TA/TT: OR = 1.12, 95%CI = 1.02–1.22, P_{heterogeneity} < 0.001; TA/AA vs. TT: OR = 1.06, 95%CI = 1.01–1.12, P_{heterogeneity} < 0.001). Stratified analysis by cancer type revealed that the STK rs2273535 polymorphism may contribute to the risk of breast cancer (AA vs. TT: OR = 1.21, 95%CI = 1.01–1.44, P_{heterogeneity} = 0.002), colorectal cancer (AA vs. TA/TT: OR = 1.24, 95%CI = 1.05–1.47, P_{heterogeneity} = 0.124), and esophageal cancer (AA vs. TA/TT: OR = 1.19, 95%CI = 1.02–1.39, P_{heterogeneity} = 0.148). Further subgroup analysis by ethnicity indicated that there was a statistically increased cancer risk in Asians (AA vs. TA/TT: OR = 1.20, 95%CI = 1.05–1.37, P_{heterogeneity} = 0.004). Conclusion: This meta-analysis suggests that the STK15 rs2273535 polymorphism is a candidate gene polymorphism for cancer susceptibility, especially in Asian populations.     

IκBα polymorphisms were associated with increased risk of gastric cancer in a southern Chinese population: a case-control study

AimNuclear factor-kappa B inhibitor alpha (IκBα) polymorphisms were found to be associated with inflammatory diseases. However, the association between IκBα polymorphisms with gastric cancer is still unknown. We aim to investigate the association between IκBα polymorphisms and gastric cancer risk in a large population-based case–control study among southern Chinese.Main methodsA population-based case–control study was conducted between 1999 and 2006 in Guangdong Province, China. A total of 1010 gastric cancer patients and 1500 healthy controls were enrolled in this study. IκBα polymorphisms were identified by sequencing of IκBα gene ranging from the 2 kb promoter region to the 3.5 kb genomic region. Polymorphisms in IκBα were analyzed by TaqMan SNP genotyping assay.Key findingsrs17103265 deletion homozygote (?/?) had significantly increased gastric cancer risk (OR = 2.11, 95% CI = 1.17–3.83, P = 0.01), compared with rs17103265 T homozygote (TT). rs17103265 (?/?) genotype was significantly associated with increased risk of intestinal-type gastric cancer with (OR = 2.21, 95% CI = 1.19–4.08, P = 0.01), but not with the diffuse or mix type of gastric cancer. rs17103265 (?/?) was associated with poorly differentiated gastric cancer (OR = 2.05, 95% CI = 1.07–3.94, P = 0.03), but not with moderately or well differentiated gastric cancer. A significant decrease in luciferase activity was observed in rs17103265 deletion allele as compared with the vector containing the rs17103265 T allele (P < 0.0001). rs17103265 polymorphism was not associated with the prognosis of gastric cancer patients.SignificanceIκBα rs17103265 deletion homozygote is a novel genetic risk factor for gastric carcinogenesis, especially for the development of certain subtypes of gastric cancer in southern Chinese population.     

Prolonged breastfeeding reduces risk of breast cancer in Sri Lankan women: A case–control study

Goal: To assess the association between duration of breastfeeding and the risk of breast cancer in Sri Lankan women. Methods: We conducted a case–control study in women aged 30–64 years in selected health care facilities in the Western province. A total of 100 recent cases of breast cancer (histologically confirmed) and 203 controls (age and parity matched) were included. Detailed information regarding breastfeeding, menstruation, reproductive factors, passive smoking and other confounders was collected using a structured questionnaire. Adjusted odds ratios and 95% confidence intervals were calculated using multiple logistic regressions. Principle results: Multivariate analysis found that those women who breastfed for ≥24 months during lifetime had significantly lower risk of breast cancer than those who breastfed for less than 24 months (OR = 0.40; 95%CI = 0.22, 0.73). Compared to 0–11 months of lifetime breastfeeding, there was a 66.3% reduction in breast cancer risk in women who breastfed for 12–23 months, 87.4% reduction in 24–35 months and 94% reduction in 36–47 months categories. The mean duration of breastfeeding per child for ≥12 months was also associated with reduced risk of breast cancer (OR = 0.52; 95%CI = 0.28, 0.94). The significant factors associated with increased risk of breast cancer were: post-menopausal women (OR = 1.74; 95%CI = 1.01, 3.01); having an abortion in the past (OR = 3.42; 95%CI = 1.75, 6.66) and exposure to passive smoking (OR = 2.96, 95%CI = 1.53, 5.75). Major conclusions: Prolonged breastfeeding significantly reduces the risk of breast cancer and this protective effect was supported by a dose–response relationship. Risk due to passive smoking should be emphasized in anti-smoking programmes.     

Family history of cancer and non-malignant diseases and risk of childhood acute lymphoblastic leukemia: a Children's Oncology Group Study

Background: Studies of family history of cancer and non-malignant diseases in childhood acute lymphoblastic leukemia (ALL) show inconsistent findings. Most studies show no increased risk with family history of cancer. Non-malignant diseases such as allergic diseases, autoimmune diseases, birth defects and thyroid diseases have been reported to be associated with ALL. Methods: We conducted a case-control study of family history of cancer and selected non-malignant conditions (allergic diseases, autoimmune diseases, birth defects, and thyroid diseases). ALL cases were obtained from Children's Cancer Group institutions from January 1989 to June 1993. Controls were recruited via random digit dialing. Family history for first degree relatives and grandparents of ALL cases and controls was collected by structured telephone questionnaires. Conditional logistical regression was used to calculate odds ratios adjusting for potential confounders. Results: We found a borderline association of ALL and having a family member with a history of cancer in cases (n = 1842) compared to controls (n = 1986) (OR = 0.98, 95%CI = 0.93, 1.00) and an inverse association for esophageal cancer based on small numbers. Family history of food and drug allergies demonstrated a modestly reduced risk (OR = 0.83, 95%CI = 0.73, 0.95) as did family history of rheumatoid arthritis (OR = 0.79, 95%CI = 0.65, 0.96). There were no associations with family history of any autoimmune diseases, immunodeficiencies, birth defects, thyroid diseases and risk of childhood ALL. Conclusions: These results show no association of overall family history of cancer with childhood ALL, while providing additional evidence for an inverse association with family history of allergic disease. Two potentially new associations of ALL with family history of esophageal cancer and rheumatoid arthritis require confirmation in other studies and validation with medical records.     

Polymorphisms in MSH2 gene and risk of gastric cancer, and interactions with lifestyle factors in a Chinese population

Background: Although polymorphisms in DNA mismatch repair (MMR) gene MSH2 have been associated with risks of many cancers, little is known about their etiology role in gastric cancer (GC) and the potential interacting role with lifestyle factors known to damage DNA. Methods: A population-based study was conducted in 3 counties (Jintan, Taixing and Huaian) of Jiangsu Province, the high-risk areas of GC in China. We investigated the association of polymorphisms IVS12?6T>C and IVS10+12G>A in MSH2 gene with the risk of GC and the potential gene–lifestyle interaction. Results: The risk of GC was found to be associated with the IVS12?6C allele (CC vs TT, OR = 2.34, 95% CI: 1.17–4.71) and IVS10+12A allele (GA or AA vs GG, OR = 1.55, 95% CI: 1.14–2.21; and GA vs GG, OR = 1.51, 95% CI: 1.04–2.17). Stratified analysis indicated that an increased risk of GC also was observed in: suspected familial subjects carrying the IVS12?6T>C (OR = 1.68, 95% CI: 1.27–2.66) or IVS10+12G>A (OR = 2.57, 95% CI: 1.53–4.10); or younger subjects carrying the IVS12?6T>C (OR = 2.15, 95% CI: 1.24–3.91) or IVS10+12G>A (OR = 2.23, 95% CI: 1.20–4.33); or male subjects carrying the IVS10+12G>A (OR = 1.64; 95% CI: 1.10–2.54). Furthermore, the combined IVS12?6CC and IVS10+12AA genotypes also significantly increased the risk of GC (OR = 2.12, 95% CI: 1.22–3.66). Statistically significant interactions were observed between: IVS10+12G>A and drinking, high pickled food or fried food intake (OR = 2.32; 95% CI: 1.43–3.78, OR = 2.55; 95% CI: 1.48–4.21 and OR = 2.88; 95% CI: 1.70–4.94, respectively); and IVS12?6T>C and high pickled food intake or fried food intake (OR = 2.65; 95% CI: 1.62–4.47 and OR = 2.48; 95% CI: 1.42–4.13, respectively). Conclusion: The IVS10+12G>A and IVS12?6T>C polymorphisms in MSH2 gene appear to be associated with risk of GC in this Chinese population. Risk for GC, stratified by related genotypes, was further modified by drinking, high pickled food or fried food intake. Larger prospective studies are needed to confirm these findings.     

SWI/SNF gene variants and glioma risk and outcome

Background: The human SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complex plays essential roles in a variety of cellular processes and has been implicated in human cancer. However, the role of germline genetic variants in this complex in relation to cancer risk is not well studied. Methods: We assessed the association of 16 variants in the catalytic subunits (SMARCA2 and SMARCA4) of the SWI/SNF complex with the risk of glioma subtypes (lower grade astrocytoma, oligodendroglioma and glioblastoma [GBM]) and with mortality from high-grade tumors (GBM) in a multicenter US case–control study that included 561 cases and 574 controls. Associations were estimated with odds ratios (OR, for risk) or hazards ratios (HR, for mortality) with 95% confidence intervals (CI). False discovery rate (FDR-q) was used to control for multiple testing in risk associations. Results: None of the investigated SNPs was associated with overall glioma risk. However, analyses according to histological subtypes revealed a statistically significant increased risk of oligodendroglioma in association with SMARCA2 rs2296212 (OR = 4.05, 95%CI = 1.11–14.80, P = 0.030, q = 0.08) and rs4741651 (OR = 4.68, 95%CI = 1.43–15.30, P = 0.011, q = 0.08) and SMARCA4 rs11672232 (OR = 1.90, 95%CI = 1.01–3.58, P = 0.048, q = 0.08) and rs12232780 (OR = 2.14, 95%CI = 1.06–4.33, P = 0.035, q = 0.08). No significant risk associations were observed for GBM or lower grade astrocytoma. Suggestive associations with GBM mortality were not validated in the Cancer Genome Atlas. Conclusion: Our findings suggest that genetic variants in SMARCA2 and SMARCA4 influence the risk of oligodendroglioma. Further research is warranted on the SWI/SNF complex genes and epigenetic mechanisms more generally in the development of glioma in adults.     

Does night work increase the risk of breast cancer? A systematic review and meta-analysis of epidemiological studies

Objective: To conduct a systematic review, with meta-analysis, of studies assessing the association between night work and the risk of breast cancer, using available epidemiological evidence. Method: Relevant studies were identified by searching several databases and the reference lists of retrieved articles. We combined the relative risks (RR) from individual studies using a random-effects model. Subgroup analysis was carried out as the data showed statistically significant heterogeneity. Results: Thirteen studies consisting of eight case–control studies and five cohort studies were included in the analysis. In the combined analysis of all studies, night work was associated with an increased risk for breast cancer (RR = 1.20, 95%CI = 1.08–1.33). The higher-quality studies showed a similar finding with a pooled RR of 1.40 (95%CI = 1.13–1.73). Both case–control studies (RR = 1.32, 95%CI = 1.17–1.50) and cohort studies (RR = 1.08, 95%CI = 0.97–1.21) showed a positive association between night work and the risk of breast cancer. No publication bias was found either from Begg's funnel plot (P = 0.086) or the Egger's test (P = 0.107). Additional well-conducted and large-scale epidemiological studies are needed.     

Variants of the MTHFR gene and susceptibility to acute lymphoblastic leukemia in children: a synthesis of genetic association studies

Background: Acute lymphoblastic leukemia (ALL) is a complex disease with genetic background. The genetic association studies (GAS) that investigated the association between ALL and the MTHFR C677T and A1298C gene variants have produced contradictory or inconclusive results. Materials and methods: In order to decrease the uncertainty of estimated genetic risk effects, a meticulous meta-analysis of published GAS related the variants in the MTFHR gene with susceptibility to ALL was conducted. The risk effects were estimated based on the odds ratio (OR) of the allele contrast and the generalized odds ratio (OR_G). Cumulative and recursive cumulative meta-analyses were also performed.ResultsThe analysis showed marginal significant association for the C677T variant, overall [OR = 0.91 (0.82–1.00) and OR_G = 0.89 (0.79–1.01)], and in Whites [OR = 0.88 (0.77–0.99) and OR_G = 0.85 (0.73–0.99)]. The A1298C variant produced non-significant results. For both variants, the cumulative meta-analysis did not show a trend of association as evidence accumulates and the recursive cumulative meta-analysis indicated lack of sufficient evidence for denying or claiming an association. Conclusion: The current evidence is not sufficient to draw definite conclusions regarding the association of MTHFR variants and development of ALL.     

Polymorphisms of tumor-related genes IL-10, PSCA,MTRR and NOC3L are associated with the risk of gastric cancer in the Chinese Han population

BackgroundGastric cancer is the fourth most common cancer in the world. Environmental and genetic factors both play critical roles in the etiology of gastric cancer. Hundreds of SNPs have been identified to have association with the risk of gastric cancer in many races. In this study, 25 SNPs in genes for IL-10, IL-1B, MTRR, TNF-а, PSCA, PLCE1 and NOC3L were analyzed to further evaluate their associations with gastric cancer susceptibility in the Chinese Han population.MethodsTwo hundred and seventy nine gastric cancer patients and 296 healthy controls were recruited in this study. SNP genotyping was conducted using Sequenom MassARRAY RS1000. Data management and statistical analyses were conducted by Sequenom Typer 4.0 Software and Pearson's χ² test.ResultsOne protective allele and three risk alleles for gastric cancer patients were found in this study. The allele “G” of rs1801394 in MTRR showed an association with a decreased risk of gastric cancer: odds ratio (OR) = 0.74, 95% confidence interval (95% CI) = 0.57–0.97, P = 0.030 in the additive model; OR = 0.495, 95% CI = 0.26–0.95, P = 0.034 in the recessive model. The other three SNPs, the allele “C” of rs1800871 in IL10 (OR = 1.33, 95% CI = 1.04–1.90; P = 0.026 in the additive model; OR = 1.46, 95% CI = 1.04–2.06; P = 0.030 in the recessive model), the allele “A” of rs2976391 in PSCA (OR = 1.30, 95% CI = 1.01–1.66; P = 0.041 in the additive model and OR = 1.48, 95% CI = 1.04–2.11, P = 0.028 in the recessive model), and the allele “G” of rs17109928 in NOC3L gene (OR = 1.34, 95% CI = 1.01–1.78; P = 0.042 by additive model analysis; OR = 1.47, 95% CI = 1.04–2.07, P = 0.028 by dominant model analysis), showed an association with an increased risk of gastric cancer.ConclusionsThese results indicate the importance of four gastric cancer susceptibility polymorphisms of IL-10, NOC3L, PSCA and MTRR in the Chinese Han population, which could be used in the determination of gastric cancer risk in clinical practice.     

CYP1AI, glutathione S-transferase gene polymorphisms and risk of Polycythemia vera

Background: Associations between polymorphisms for gene encoding enzymes involved in biotransformation of xenobiotics and susceptibility to several cancers have been shown in several studies. The aim of the present study was to evaluate the association of polymorphisms of cytochrome P450 (CYP1A1) and GST deletions with the incidence of Polycythemia vera (PV) among the Jordanian population. Methods: The study included 61 PV patients and 70 cancer-free healthy controls. CYP1A1 (m1, m2, m3, m4) and GST (T1, M1) genotypes were determined by polymerase chain reaction and restriction fragment length polymorphism. The risk of cancer associated with gene polymorphisms was estimated by calculations of odds ratio (ORs) and confidence intervals (95% CIs) using Mantel–Haenszel statistics. Results: A statistically significant difference between the PV group and the control group was observed in the case of GSTM1 null genotype with 3.38 fold increase in risk of developing PV (95% CI = 1.63–7.01, p = 0.001) while GSTT1 null genotype showed no significance (OR = 1.11; 95% CI = 0.50–2.44, p = 0.38). No significant association was found between the CYP1A1 mutant genotypes (m1, m2, m4) and PV. The m3 genotype was absent in both patients and controls. Interestingly, a substantial significant increase of PV risk for the combination of GSTM1 null genotype and CYP1A1 m1 (T6235C) genotype was observed (OR = 4.38; 95% CI = 1.15–16.73, p = .02). Furthermore, the present case–control study showed that the studied Jordanian population generally resembles Caucasian populations with respect to the frequencies of CYP1A1 polymorphisms. Conclusion: Our data suggests that GSTM1 null genotype alone and in combination with CYP1A1 m1 genotype may be predisposing risk factors for PV in the Jordanian population.     

An updated meta-analysis on the association of TGF-β1 gene promoter -509C/T polymorphism with colorectal cancer risk

AimPublished data on the association between transforming growth factor-β1 (TGF-β1) gene promoter-509C/T polymorphism and colorectal cancer (CRC) risk are inconsistent and inconclusive. To derive a more precise estimation of this association, a meta-analysis was carried out.MethodsMeta-analysis was performed to evaluate reported studies of the relationship between TGF-β1 gene promoter-509C/T polymorphism and colorectal cancer risk using fixed-effects model and random-effects model.ResultsWe observed an increased colorectal cancer risk among subjects carrying TGF-β1 gene promoter-509CC + CT genotype (odds ratio (OR) = 1.18%, 95% confidence interval (95% CI): 1.06–1.32) using 4440/6785 cases/controls in total population. We observed an increased risk of the TGF-β1 gene promoter -509CC, CT and CC + CT polymorphisms for colorectal cancer in population-based study (OR = 1.36, 95% CI: 1.19–1.56, OR = 1.18, 95% CI: 1.03–1.34 and OR = 1.26, 95% CI: 1.12–1.43, respectively) in stratified analysis. We observed an increased colorectal risk among CC and CC + CT carriers in European and American population (OR = 1.22, 95% CI: 1.04–1.43 and OR = 1.18, 95% CI: 1.02–1.38, respectively). We also observed an increased risk of colon cancer among subjects carrying CC + CT genotype (OR = 1.31, 95% CI: 1.05–1.63).ConclusionsThe present meta-analysis results suggest that TGF-β1 gene promoter -509C allele variant is a possible risk factor for developing colorectal cancer. Recommendations for further studies include pooling of individual data to verify results from the study and to facilitate evaluation of multigenic effects and detailed analysis of effect modification by environmental and lifestyle factors.     

Risk factors for multiple myeloma: A hospital-based case-control study in Northwest China

BackgroundThe distinctive racial/ethnic and geographic distribution of multiple myeloma (MM) suggests that both family history and environmental factors may contribute to its development.MethodsA hospital-based case–control study consisting of 220 confirmed MM cases and 220 individually matched patient controls, by sex, age and hospital was carried out at 5 major hospitals in Northwest China. A questionnaire was used to obtain information on demographics, family history, and the frequency of food items consumed.ResultsBased on multivariate analysis, a significant association between the risk of MM and family history of cancers in first degree relatives was observed (OR = 4.03, 95% CI: 2.50–6.52). Fried food, cured/smoked food, black tea, and fish were not significantly associated with the risk of MM. Intake of shallot and garlic (OR = 0.60, 95% CI: 0.43–0.85), soy food (OR = 0.52, 95% CI: 0.36–0.75) and green tea (OR = 0.38, 95% CI: 0.27–0.53) was significantly associated with a reduced risk of MM. In contrast, intake of brined vegetables and pickle was significantly associated with an increased risk (OR = 2.03, 95% CI: 1.41–2.93). A more than multiplicative interaction on the decreased risk of MM was found between shallot/garlic and soy food.ConclusionOur study in Northwest China found an increased risk of MM with a family history of cancer, a diet characterized by low consumption of garlic, green tea and soy foods, and high consumption of pickled vegetables. The effect of green tea in reducing the risk of MM is an interesting new finding which should be further confirmed.     

Promoter polymorphism (−590, T/C) of interleukin 4 (IL4) gene is associated with rheumatoid arthritis: An updated meta-analysis

Rheumatoid arthritis (RA) is a chronic disease. It causes chronic inflammation of the joint. Recent studies suggested that interleukin 4 (IL4) contributes to susceptibility and severity of rheumatoid arthritis (RA). Especially, it was reported that promoter polymorphism (−590, T/C) of IL4 gene has been associated with susceptibility of RA. The aim of present study was to investigate whether the promoter polymorphism (−590, T/C) of IL4 gene is associated with the susceptibility of RA using meta-analysis. And in order to perform meta-analysis, comprehensive meta analysis program was used. Genetic models (co-dominant, dominant, recessive, and allele) were used to determine odds ratios (ORs), 95% confidence intervals (CIs), and P values. Nine case-control studies with case and control design were included in this meta-analysis. Overall, meta-analysis revealed a strong association with susceptibility of RA [OR = 1.303, 95% CI = 1.093–1.554, P = 0.003 in allele model (C vs. T); OR = 1.247, 95% CI = 1.054–1.474, P = 0.010 in dominant model (CC vs. CT + TT); OR = 2.148, 95% CI = 1.263–3.651, P = 0.005 in recessive model (CC + CT vs. TT)]. Our data demonstrated that promoter polymorphism (−590, T/C) of IL4 gene may be contributed to susceptibility of RA. However, more studies with a larger sample size are needed to provide more precise evidence.     

Association between interleukin 15 receptor, alpha (IL15RA) polymorphism and Korean patients with ossification of the posterior longitudinal ligament

ObjectivesRecently, a number of evidences have been reported concerning the genetic factor involved in the development of ossification of the posterior longitudinal ligament (OPLL). The purpose of this study was to investigate single nucleotide polymorphisms (SNPs) of the interleukin 15 receptor, alpha (IL15RA) gene as a risk factor in Korean patients with OPLL.DesignTo investigate the genetic association, two coding SNPs (rs2296139, Thr73Thr; rs2228059, Asn182Thr) in IL15RA were genotyped in 166 OPLL patients and 230 control subjects. SNPStats, SNPAnalyzer, and Helixtree programs were used for association analysis.ResultsIn the present study, we found the association between a missense SNP (rs2228059) and the risk of OPLL in codominant (p = 0.0028, OR = 1.58, 95% CI = 1.17–2.14), dominant (p = 0.0071, OR = 1.82, 95% CI = 1.17–2.82), and recessive models (p = 0.036, OR = 1.79, 95% CI = 1.04–3.09). The frequency of rs2228059 allele was significantly associated with the susceptibility of OPLL (p = 0.0043, OR = 1.52, 95% CI = 1.14–2.02). After Bonferroni correction, the missense SNP (rs2228059, Asn182Thr) still had significant correlations (p = 0.0056 in codominant model; p = 0.0142 in dominant model; p = 0.0086 in allele analysis). Haplotype variation in IL15RA was associated with OPLL (global haplotype test, p = 0.025).ConclusionsThese results suggest that IL15RA polymorphism may be associated with the susceptibility of OPLL in Korean population.     

Factors associated with inadequate colorectal cancer screening with flexible sigmoidoscopy

Background and study aim: Inadequate colorectal cancer screening wastes limited endoscopic resources. We examined patients factors associated with inadequate flexible sigmoidoscopy (FSG) screening at baseline screening and repeat screening 3–5 years later in 10 geographically-dispersed screening centers participating in the ongoing Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Methods: A total of 64,554 participants (aged 55–74) completed baseline questionnaires and underwent FSG at baseline. Of these, 39,385 participants returned for repeat screening. We used logistic regression models to assess factors that are associated with inadequate FSG (defined as a study in which the depth of insertion of FSG was <50 cm or visual inspection was limited to <90% of the mucosal surface but without detection of a polyp or mass). Results: Of 7084 (11%) participants with inadequate FSG at baseline, 6496 (91.7%) had <50 cm depth of insertion (75.3% due to patient discomfort) and 500 (7.1%) participants had adequate depth of insertion but suboptimal bowel preparation. Compared to 55–59 year age group, advancing age in 5-year increments (odds ratios (OR) from 1.08 to 1.51) and female sex (OR = 2.40; 95% confidence interval (CI): 2.27–2.54) were associated with inadequate FSG. Obesity (BMI >30 kg/m²) was associated with reduced odds (OR = 0.67; 95% CI: 0.62–0.72). Inadequate FSG screening at baseline was associated with inadequate FSG at repeat screening (OR = 6.24; 95% CI: 5.78–6.75). Conclusions: Sedation should be considered for patients with inadequate FSG or an alternative colorectal cancer screening method should be recommended.     

Postmenopausal hormone therapy and ductal carcinoma in situ: a population-based case-control study

Background and aim: The relationship between hormone therapy (HT) and invasive breast cancer has been extensively investigated, but the relationship between HT and in situ breast cancer has received relatively little attention. We examined the relationship between HT and ductal carcinoma in situ (DCIS) among postmenopausal women who participated in a population-based case–control study in Connecticut, USA. Methods: This analysis included 1179 post-menopausal women (603 controls and 576 cases), who comprised a subset of a population-based case–control study that included all incident cases of breast carcinoma in situ (BCIS) in Connecticut and frequency-matched controls by 5-year age intervals. Results: We found no association between DCIS and ever use of any HT (adjusted odds ratio (OR) = 0.85, 95% confidence interval (CI): 0.65–1.11); of estrogen alone (adjusted OR = 0.93; 95% CI: 0.68–1.29) or of estrogen and progesterone (adjusted OR = 0.75; 95% CI: 0.52–1.08). There was also no association between DCIS and current use of these hormones. In addition, estimated risk of DCIS did not increase with duration of use of these preparations. Conclusions: These results add to a small literature that remains inconclusive. To determine whether HT poses risk of in situ breast cancer, larger studies with greater power and precise control of important covariates (e.g., mammography screening) are needed, as are meta-analyses of available data.     

A potentially functional polymorphism in the promoter region of let-7 family is associated with survival of hepatocellular carcinoma

Background: The let-7 family plays a vital role in the normal cellular activity of liver cells and the carcinogenesis of hepatocellular carcinoma (HCC). In the previous study, we have detected the association between single nucleotide polymorphisms (SNPs) in the promoter region of let-7 and susceptibility to HCC. However, it is still unknown whether these polymorphisms are associated with HCC prognosis. Methods: We investigated the effect of two potentially functional SNPs in the promoter region of let-7 family, rs10877887 (T > C) and rs13293512 (T > C), on the overall survival of 331 HCC patients. Log-rank test and Cox proportional hazard models were used for the survival analyses. Results: We found that HCC patients carrying the C allele of rs10877887 had a significantly increased death risk (adjusted HR = 1.22, 95%CI = 1.02–1.47, P = 0.03 in the additive model), compared to those with T allele. In the stratified analysis, the risk effect was evident in HCC patients with Barcelona Clinic Liver Cancer (BCLC) stage B (adjusted HR = 1.24, 95%CI = 1.02–1.51, P = 0.03) and in those who received chemotherapy or intervention (adjusted HR = 1.25, 95%CI = 1.02–1.53, P = 0.04). Conclusions: Our results suggest that rs10877887 in the promoter region of let-7 may be a prognostic biomarker for HCC patients, which need the validation from other larger studies in different populations.     

Genomic damages in peripheral blood lymphocytes and association with polymorphisms of three glutathione S-transferases in workers exposed to formaldehyde

DNA and chromosome damages in peripheral blood lymphocytes were evaluated in 151 workers occupationally exposed to formaldehyde (FA) and 112 non-FA exposed controls. The effects of polymorphisms in three glutathione-S-transferase (GSTs) genes on the DNA and chromosome damages were assessed as well. Alkaline comet assay and cytokinesis-block micronucleus (CBMN) assay were used to determine DNA and chromosome damages, respectively. The genotypes of GSTP1 (Ile105Val), GSTT1, and GSTM1 were assayed. The mean 8-h time-weighted average (TWA) concentrations of FA in two plywood factories were 0.83 ppm (range: 0.08–6.30 ppm). FA-exposed workers had higher olive tail moment (TM) and CBMN frequency compared with controls (Olive TM, 3.54, 95%CI = 3.19–3.93 vs. 0.93, 95%CI = 0.78–1.10, P < 0.01; CBMN frequency, 5.51 ± 3.37 vs. 2.67 ± 1.32, P < 0.01). Olive TM and the CBMN frequency also had a dose-dependent relation with the personal FA exposure. Significant association between FA exposure history and olive TM and CBMN frequency were also identified. The level of olive TM was slightly higher in FA-exposed workers with GSTM1 null genotype than those with non-null genotype (3.86, 95%CI = 3.31–4.50 vs. 3.27, 95%CI = 2.83–3.78, P = 0.07) with adjustment of covariates. We also found that FA-exposed workers carrying GSTP1 Val allele had a slightly higher CBMN frequency compared with workers carrying only the wild-type allele (6.32 ± 3.78 vs. 5.01 ± 2.98, P = 0.05). Our results suggest that the FA exposure in this occupational population increased DNA and chromosome damages and polymorphisms in GSTs genes may modulate the genotoxic effects of FA exposure.