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Chronic hepatitis B virus (HBV) infection is a challenging global health problem. To identify genetic loci involved in chronic HBV infection, we designed a three-phase genome-wide association study in Han Chinese populations. The discovery phase included 951 HBV carriers (cases) and 937 individuals who had naturally cleared HBV infection (controls) and was followed by independent replications with a total of 2,248 cases and 3,051 controls and additional replications with 1,982 HBV carriers and 2,622 controls from the general population. We identified two new loci associated with chronic HBV infection: rs3130542 at 6p21.33 (near HLA-C, odds ratio (OR) = 1.33, P = 9.49 × 10−14) and rs4821116 at 22q11.21 (in UBE2L3, OR = 0.82, P = 1.71 × 10−12). Additionally, we replicated the previously identified associations of HLA-DP and HLA-DQ variants at 6p21.32 with chronic HBV infection. These findings highlight the importance of HLA-C and UBE2L3 in the clearance of HBV infection in addition to HLA-DP and HLA-DQ. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To determine epidemiologic features of an Escherichia coli O157:H7 outbreak occurred in Xuzhou, Jiangsu Province, China in 1999, and assess the incidence of E. coli O157:H7 in diarrhea patients and host animals and its relationship with disease onset, and provide a scientific basis for establishing prevention and control strategies. Methods: Epidemiological, microbiological, and molecular methods were performed to identify risk factors and describe the ecology of E. coli O157:H7 in the environment. Results: From May to September, in 1999, 99 cases of E. coli O157:H7 infection were confirmed. Fifty-six patients were enrolled in the case-control study. Bad personal health habits and poor sanitary conditions in the kitchen were associated with increased risks of infection, whereas hand washing was protective. The household survey indicated that residents in the epidemic region during the outbreak had higher than expected rates of diarrhea. The total E. coli O157:H7 carrier rate in the livestock was 12.36%(22/178), specifically 19.15% in cattle, 12.50% in goat, and 11.11% in swine. Numerical analysis of pulsed-field gel electrophoresis(PFGE) profiles divided strains into two clusters with 77.5% homology. One cluster contained 11 strains isolated from diarrheal patients, foods, and animals. The other cluster comprised 10 strains from patients and environment. Conclusion: In a large outbreak of E. coli O157:H7 infection among predominantly elderly residents in Xuzhou, high rates of carriage of E. coli O157: H7 among host animals most likely resulted in contamination of the environment, thereby leading to the outbreak. Effective and preventive control measures should be taken to avoid contamination, including environmental and family health improvement, good personal hygiene, and safe food handling practices. [Copyright &y& Elsevier]

As a high-risk factor of perinatal HBV transmission, the potential role of maternal hepatitis B e antigen (HBeAg) to guide antiviral prophylaxis has not yet been fully reported. This large prospective cohort study enrolled 1177 hepatitis B surface antigen (HBsAg)-positive pregnant women without antiviral treatment and their newborns. HBeAg, HBsAg, and viral load in maternal serum collected before delivery were measured. All the newborns were given standard passive-active immunoprophylaxis within 12 h after birth, and post-vaccination serologic testing was performed at 7 (±7d) months of age. The results revealed that 20 of the 1177 infants (1.70%) were immunoprophylaxis failure, and all their mothers were HBeAg positive. Maternal quantitative HBeAg was positively correlated with viral load ( r  = 0.83; P  < .0001) and quantitative HBsAg ( r  = 0.68; P  < .0001). The area under the receiver operating characteristic curve (AUC) for predicting immunoprophylaxis failure by maternal HBeAg was comparable to that by maternal viral load (0.871 vs 0.893; P  = .441) and HBsAg (0.871 vs 0.871; P  = .965). The optimal cutoff value of maternal quantitative HBeAg to predict perinatal infection was 2.21 log 10 PEI U/mL, and the sensitivity and specificity was 100.0% and 74.5%, respectively. According to maternal viral load >2 × 10 5 IU/mL, the sensitivity and specificity of maternal qualitative HBeAg to identify the risk of HBV MTCT for pregnant women and determine the necessity for antiviral prophylaxis was 95.5% and 92.6%, respectively. This study showed that maternal HBeAg can be a surrogate marker of HBV DNA for monitoring and evaluating whether antiviral prophylaxis is necessary for preventing perinatal HBV transmission.

Nowadays most of the hepatitis B virus (HBV) infected population are adults, among which hepatitis B e antigen (HBeAg) negative infection occupied the largest proportion of HBV infection in China. HBeAg-negative patients are heterogeneous, and the corresponding interventions are different. Therefore, it is worth researching the infection characteristics of HBeAg-negative patients to help guide the interventions.A total of 11,738 treatment-naïve HBeAg-negative adult patients were randomly selected, and their demographic and medical history information were collected. The liver biochemistry, and HBV infection biomarkers including hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), HBeAg, hepatitis B e antibody (anti-HBe), hepatitis B core antibody (anti-HBc), and hepatitis B virus deoxyribonucleic acid (HBV-DNA) levels were tested. The infection characteristics and their influencing factors were explored.Sixty percent of the patients presented HBV-DNA-positive, of which 31.2% had HBV-DNA level higher than 2000 IU/mL, and 16.5% had HBV-DNA level higher than 20,000 IU/mL. HBV-DNA levels tended to increase along with the increasing of age, and the male patients had significant higher HBV-DNA levels than the female patients. Twenty-four percent of the patients had abnormal transaminase. The male patients were more vulnerable to abnormal transaminase (30.0%) than the female patients (18.4%). Fifty-five percent patients with HBV-DNA ≥20,000 IU/mL presented abnormal alanine aminotransferase (ALT) or aspartate transaminase (AST), which was significantly higher than that of patients with HBV-DNA levels below 20,000 IU/mL (19.0-21.7%). Multivariate logistic regression analyses revealed that the male patients and the patients with higher viral load had higher risk of having abnormal liver function.A considerable number of HBeAg-negative patients were virological active and had liver damage. It is necessary and urgent to carry out regular active interventions for the chronic HBV-infected patients.

Importance: Hepatitis B virus (HBV) has been identified as a major risk factor for hepatocellular carcinoma. However, the associations between HBV infection and other cancer types are not well understood., Objective: To assess the associations between chronic HBV infection and risk of all cancer types., Design, Setting, and Participants: This population-based study involved 3 cohorts in China. The China Kadoorie Biobank (CKB) prospective cohort study, conducted between June 2004 and July 2008, used a dipstick assay for detection of serum hepatitis B surface antigen (HBsAg) among 496 732 participants to determine the association between HBV infection and risk of all cancer types. Two cohort studies were used to validate the associations by applying more precise serum HBsAg detection assays: the Qidong cohort (37 336 participants enrolled from November 2007 to April 2011) and the Changzhou nested case-control study (17 723 participants enrolled from June 2004 to September 2005). A total of 97 samples of stomach cancer tissues, 10 samples of pancreatic cancer tissues, and 9 samples of lung cancer tissues were included to assess the presence of HBV replication and expression. Statistical analysis was performed from December 2016 to October 2018., Exposures: Serum HBsAg status in the population-based stage and HBV DNA status, the expression of hepatitis B X protein, and hepatitis B core antibody (anti-HBc) in the tissue-based stage., Main Outcomes and Measures: Incidence of all cancer types during follow-up., Results: In the CKB cohort, the mean (SD) age of the 496 732 participants was 51.5 (10.7) years; 59.0% of the participants were women. After 4.4 million person-years of follow-up, participants who were HBsAg seropositive (n = 15 355) had a higher risk of hepatocellular carcinoma (hazard ratio [HR], 15.77; 95% CI, 14.15-17.57), stomach cancer (HR, 1.41; 95% CI, 1.11-1.80), colorectal cancer (HR, 1.42; 95% CI, 1.12-1.81), oral cancer (HR, 1.58; 95% CI, 1.01-2.49), pancreatic cancer (HR, 1.65; 95% CI, 1.03-2.65), and lymphoma (HR, 2.10; 95% CI, 1.34-3.31) when compared with participants who were HBsAg seronegative (n = 481 377). Because of the limitation of sample size, only associations of HBV infection with hepatocellular carcinoma and stomach cancer were validated in the Qidong cohort (hepatocellular carcinoma: HR, 17.51; 95% CI, 13.86-22.11; stomach cancer: HR, 2.02; 95% CI, 1.24-3.29); the Changzhou nested case-control study validated only an association between HBV infection and stomach cancer (odds ratio, 1.76; 95% CI, 1.04-2.98). Moreover, among 22 participants with stomach cancer from the Qidong cohort who were anti-HBc seropositive, 12 samples (54.5%) of cancer tissues were HBV DNA positive, while among 25 participants with stomach cancer who were anti-HBc seronegative, no HBV DNA was detected. The same negative and positive rate was observed in the validation set from Zhejiang Tumor Hospital (19 of 35 samples [54.3%] were HBV DNA positive). Moreover, among the 8 patients with stomach cancer from the Qidong cohort who were anti-HBc seropositive, anti-HBc and hepatitis B X protein were expressed in all of their stomach cancer tissue samples. The same phenomenon was observed in the patients with pancreatic cancer but not in the patients with lung cancer, which was consistent with the population-based results of the CKB cohort., Conclusions and Relevance: This study found that HBV infection was also associated with the risk of nonliver cancer, especially digestive system cancers among adults in China.

Background & Aims: Although non-alcoholic fatty liver disease (NAFLD) has been studied extensively, the potential risk factors for NAFLD among chronic hepatitis B (CHB) patients have not been fully known., Methods: A population-based cohort of adult CHB patients without a history of alcohol drinking or NAFLD were recruited and followed up from October 2012 to January 2015 in Jiangsu province, China. Using Cox proportional hazards regression model, potential risk factors including viral and metabolic factors for NAFLD were evaluated., Results: Two thousand three hundred and ninety-three adult CHB patients (mean age 50.7 ± 13.2 years) were included in the cohort. With 4429 person-years of follow-up, 283 individuals progressed to NAFLD with an incidence rate of 63.89/1000 person-years. Overweight and obese CHB patients had an increased risk of NAFLD (overweight adjusted hazard ratio [HR], 3.10; 95% CI, 2.29-4.18; obese HR, 8.52; 95%CI, 5.93-12.25) compared to normal weight carriers. The incidence of NAFLD was associated with concurrent type 2 diabetes mellitus (DM) (HR, 1.88; 95%CI, 1.15-3.08). However, no associations between viral factors with NAFLD incidence rate were identified. In a subgroup of participants with concurrent type 2 DM, detectable HBV DNA levels were negatively associated with the development of NAFLD (HR, 0.37; 95%CI, 0.14-0.98). There was super-multiplicative interaction between BMI and gender with respect to incidence of NAFLD, with an ROR of 2.08 (95%CI, 1.02-4.23)., Conclusion: Metabolic factors play an important role in the presence of NAFLD among Chinese CHB patients. However, viral replication factors are not related to NAFLD except among those with concurrent type 2 DM., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Seroclearance of hepatitis B surface antigen (HBsAg) has been widely studied; however, seroconversion of HBsAg and characteristics of viral load among hepatitis B e antigen (HBeAg)-negative chronic infection patients after HBsAg lost is not clear. We performed a large-scale study in a HBeAg-negative chronic infection cohort to evaluate spontaneous HBsAg seroclearance incidence from October 2012 to April 2017 in Jiangsu province, China. We also elucidated the characteristics of HBsAg seroconversion and hepatitis B virus (HBV) DNA detectability among patients who cleared HBsAg. A total of 2997 HBeAg-negative chronic infection patients (mean age 52.3 ± 12.9 years at baseline) were included. With 10 519 person-years of follow-up, 348 patients successfully spontaneously cleared HBsAg, with an incidence rate of 3.31 per 100 person-years. Patients with HBV DNA detectable ~1999 IU/mL at baseline had a lower probability of HBsAg seroclearance relative to those with undetectable HBV DNA, with a hazard ratio of 0.31 (95% CI = 0.23, 0.41). HBsAg seroconversion occurred in 37.3% of those patients who cleared HBsAg. The geometric mean of anti-HBs among those with HBsAg conversion was 79.4 mIU/mL. Female had a higher HBsAg seroconversion rate (P = 0.011). Among those with HBsAg seroclearance, 11.2% still had HBV DNA levels of higher than 100 IU/mL. Patients with higher HBV DNA at baseline had a higher risk of detectable HBV DNA levels even after HBsAg seroclearance (P < 0.001). This study reveals HBsAg seroconversion rates and HBV DNA undetectability epidemiological characteristics of patients with HBsAg seroclearance and suggests that monitoring HBV DNA is needed when managing HBeAg-negative chronic patients, even after clearing HBsAg., (© 2018 John Wiley & Sons Ltd.)

Previously, we identified UBE2L3 as a susceptibility gene for chronic hepatitis B virus (HBV) infection through genome-wide association study. Here, we analysed the association between genetic variants of UBE2L3 and the susceptibility to HBV-related hepatocellular carcinoma (HCC) and further explored its role in HCC. This case-control study included 1344 subjects who cleared HBV, 1560 HBV carriers and 1057 HBV-related HCC patients. Two single nucleotide polymorphisms (SNPs) were genotyped, including rs2266959 and rs4821116. Logistic regression analysis was performed to compute the odds ratio (OR) and 95% confidence interval (CI). We further analysed the expression of UBE2L3 and its association with pathological features based on The Cancer Genome Atlas (TCGA) data and our tissue microarray. Proliferation and migration assays were performed in hepatoma cell lines with or without UBE2L3 knockdown. Further RNA-seq analysis was performed to explore the underlying oncogenic mechanism. The variant genotypes of rs4821116 in UBE2L3 were associated with decreased risk for HCC and chronic HBV infection. Moreover, based on both TCGA and our tissue microarray data, higher levels of UBE2L3 expression were correlated with higher tumour grade, advanced tumour stage and poor survival. In vitro analysis revealed that UBE2L3 may promote hepatocyte proliferation and migration. RNA-seq analysis showed that UBE2L3 was inversely correlated with CDKN2B, a negative regulator of cell cycle, and CLDN1, loss of which may promote cancer metastasis. In conclusion, UBE2L3 may also be a susceptibility gene in HBV-related HCC, and it may promote HCC proliferation and migration by negatively regulating CDKN2B and CLDN1., (© 2018 John Wiley & Sons Ltd.)

Hepatitis B immunization programs for newborns, children, and adolescents in China have shown remarkable results. To establish whether there would be any benefit in extending the program to cover older individuals, we examined both the epidemiology of hepatitis B virus (HBV) infection and the coverage of hepatitis B vaccinations among adults born before routine vaccinations were implemented. We then evaluated the impact of hepatitis B vaccination in adults aged 20-59 years. A large-scale cross-sectional epidemiological survey of HBV infection was performed in the province of Jiangsu, south-east China, between September 2009 and March 2010. A total of 86,732 adults aged 20-59 years were included, of which 8,615 (9.9%, 95% CI = 9.7-10.1%) were HBsAg sero-positive. Self-reported vaccination status suggested that the coverage was approximately 23.7% (95% CI = 23.4-24.0%). It was shown that higher HBV vaccination coverage was associated with a lower rate of HBsAg seropositivity among adults. There was a negative correlation between hepatitis B vaccination coverage and HBsAg prevalence (correlation coefficient = -0.805, p = 0.016), which might demonstrate the combined effects of vaccination and pre-vaccination HBsAg screening. In the unvaccinated group, the HBsAg-positive rate had an obvious upward trend with age growing among 20-39 year-olds (Trend χ2 = 22.605, P<0.001), while the vaccinated group showed no such trend (Trend χ2 = 3.462, P = 0.063). Overall, hepatitis B vaccination in adults might reduce the rate of HBsAg positivity. Therefore, routine immunization of adults aged 20-39 years should be seriously considered.

Background: The interleukin-23 receptor (IL-23R) plays an important role in the T-helper 17 cell-mediated inflammatory process and is also involved in tumor immune surveillance, which may be linked to carcinogenesis in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). In this study, we hypothesized that potentially functional genetic variants of the IL-23R gene may modify HCC risk., Methods: We genotyped two single-nucleotide polymorphisms (SNPs) of IL-23R, rs6682925 and rs1884444, in a case-control study of 837 HCC cases, 899 HBV surface antigen (HBsAg)-positive controls, and 743 HBsAg-negative controls. A reporter gene assay was performed to evaluate the functional relevance of the rs6682925 SNP located at the promoter region of the IL-23R gene., Results: We found that the two SNPs were associated with the risk of HCC when compared with both the HBsAg-positive and -negative controls. When compared with all controls, IL-23R rs6682925 and rs1884444 both increased the HCC risk in a recessive genetic model [rs6682925 CC vs. TT/TC: odds ratio (OR) 1.35, 95 % confidence interval (CI) 1.07-1.70; rs1884444 GG vs. TT/TG: OR 1.36, 95 % CI 1.05-1.77]. Furthermore, the variant C allele of rs6682925 in the promoter region of IL-23R was associated with increased reporter gene activity., Conclusions: These findings indicate that genetic variants in IL-23R may contribute to HCC development.

Recent genome-wide association studies showed that four single-nucleotide polymorphisms (SNPs) in human leukocyte antigen (HLA)-DP (rs3077 and rs9277535) and HLA-DQ (rs2856718 and rs7453920) were associated with chronic hepatitis B virus (HBV) infection in Japanese populations. More than 75% of hepatocellular carcinoma (HCC) patients are attributable to persistent infection of hepatitis B virus (HBV), especially in China. We genotyped these four SNPs in 1,300 HBV-positive HCC patients, 1,344 persistent HBV carriers, and 1,344 persons with HBV natural clearance from Southeast China to further test the associations of HLA-DP/DQ variants and with risk of both HBV clearance and HCC development. Logistic regression analyses showed that HLA-DQ rs2856718 significantly decreased host HCC risk, whereas three SNPs were associated with HBV clearance (HLA-DP rs9277535 as well as HLA-DQ rs7453920 and rs2856718). In addition, HLA-DP rs3077 showed an approaching significant effect on susceptibility to HBV persistent infection and HCC development when considering multiple testing adjustments. Taken together, we report, for the first time, that genetic variants in the HLA-DP and HLA-DQ loci may be marker SNPs for risk of both HBV clearance and HCC development., (Copyright © 2011 American Association for the Study of Liver Diseases.)

Background: MiR-106b-25 cluster, hosted in intron 13 of MCM7, may play integral roles in diverse processes including immune response and tumorigenesis. A single nucleotide polymorphism (SNP), rs999885, is located in the promoter region of MCM7., Methods: We performed a case-control study including 1300 HBV-positive hepatocellular carcinoma (HCC) cases, 1344 HBV persistent carriers and 1344 subjects with HBV natural clearance to test the association between rs999885 and the risk of HBV persistent infection and HCC. We also investigated the genotype-expression correlation between rs999885 and miR-106b-25 cluster in 25 pairs of HCC and adjacent non-tumor liver tissues., Results: Compared with the HBV natural clearance subjects carrying rs999885 AA genotype, those with AG/GG genotypes had a decreased risk of chronic HBV infection with an adjusted odds ratio (OR) of 0.79 [95% confidence intervals (CIs) = 0.67-0.93]. However, the AG/GG genotypes were significantly associated with an increased HCC risk in HBV persistent carriers (adjusted OR = 1.25, 95% CIs = 1.06-1.47). Expression analysis revealed that the expression level of miR-106b-25 cluster was significantly higher in AG/GG carriers than those in AA carriers in non-tumor liver tissues., Conclusions: These findings indicate that the A to G base change of rs999885 may provide a protective effect against chronic HBV infection but an increased risk for HCC in HBV persistent carriers by altering the expression of the miR-106b-25 cluster.

Matrix metallopeptidase-9 (MMP-9) plays a pivotal role in vascular remodeling and development of atherosclerotic lesion. The potentially functional MMP-9 polymorphisms may contribute to the susceptibility of coronary artery disease (CAD). A case-control study composed of 762 CAD cases and 555 CAD-free controls was conducted in a Chinese population to investigate the association between the MMP-9 -1562 C>T, R279Q, P574R and R668Q polymorphisms and CAD risk. It was found that the variant genotypes of R279Q, P574R and R668Q were associated with a non-significant decreased risk of CAD when compared with their wild-type genotypes, respectively, Furthermore, compared with those without any variant genotypes for these four nonsynonymouse loci, individuals carrying all four variant genotypes (-1562 CT/TT, 279 RQ/QQ, 574 PR/RR and 668 RQ/QQ) had a 51% decreased risk of CAD (adjusted OR = 0.49; 95% CI = 0.26-0.95, P = 0.033). Although no significant main effects were observed for MMP-9 -1562 C>T locus on CAD risk, variant genotypes of -1562 C>T were associated with a 2.53 increased risk of CAD in subjects with diabetes mellitus (DM) (95% CI = 1.18-5.45, P = 0.018). In CAD cases, variant genotypes of -1562 C>T were associated with a significantly increased risk of MI (adjusted OR, 1.48, 95% CI, 1.01-2.20, P = 0.048). These findings suggest that MMP-9 R279Q, P574R and R668Q may have combined effect in the occurrence of CAD and -1562 CT/TT genotypes may contribute to CAD in diabetics and MI in CAD patients.

p21(Cip1) and p27(Kip1) are cyclin-dependent kinase inhibitors, which can arrest cell proliferation and serve as tumor suppressors. Reduced protein expression of p21(Cip1) and p27(Kip1) was frequently observed in a subset of cancers, including breast cancer. In this study, we hypothesized that genetic variants in CDKN1A (encode for p21(Cip1)) and CDKN1B (encode for p27(Kip1)) may modulate the risk of breast cancer. To test this hypothesis, we evaluated the associations of the polymorphisms of Ser31Arg and C+20T in CDKN1A and C-79T and Gly109Val in CDKN1B, as well as their combinations, with breast cancer risk in a case-control study of 368 breast cancer cases and 467 cancer-free controls in a Chinese population. We found that a significantly increased risk of breast cancer was associated with the variant genotypes of CDKN1B C-79T [adjusted OR = 1.43 (95% CI = 1.03-1.98) for -79TC/TT], compared with the -79CC genotype, but no associations were observed for other variant genotypes. However, the combined variant genotypes of the 4 loci were associated with a significantly increased breast cancer risk (adjusted OR = 1.49, 95% CI = 1.11-2.01 among subjects carrying 3 or more variant alleles), especially among premenopausal women (adjusted OR= 2.30, 95% CI = 1.45-3.66). Furthermore, in premenopausal women, this significant association remained unchanged, after including other individual risk factors in the multivariate logistic regression model, suggesting an independent role of CDKN1A and CDKN1B variants in breast cancer risk. Although the exact biological mechanism remains to be explored, our findings suggest possible involvement of CDKN1A and CDKN1B variants in the etiology of breast cancer. Further large and functional studies are needed to confirm our findings.

MDM2 is a phosphoprotein that interacts with P53 and inhibits its activity. Recently, a T/G substitution (SNP309) in the promoter of MDM2 was identified and has been demonstrated to be associated with an increased MDM2 expression and a significantly earlier age of onset of several tumors, including breast cancer. To test the hypothesis that this functional variant in the MDM2 promoter is associated with risk of breast cancer, we conducted a molecular epidemiological study of 366 breast cancer cases (BC), 263 patients with benign breast diseases (BBD) and 605 cancer-free controls in China, in which we genotyped this T/G variant and another common insertion/deletion polymorphism (Del1518) in the MDM2 promoter and evaluated the associations between these two polymorphisms and breast cancer risk. We found that the variant allele frequencies of these two polymorphisms were not statistically different between the cases and controls (SNP309G: 0.500, 0.542, and 0.506 in BC, BBD, and controls, respectively, and Del1518-: 0.296, 0.308, and 0.297 in BC, BBD, and controls, respectively). Logistic regression analyses revealed that the variant genotypes of both MDM2 SNP309 and Del1518 polymorphisms were not significantly associated with risk of breast cancer (adjusted OR, 1.03; 95% CI, 0.74-1.42 for SNP309 TG and GG; and adjusted OR, 1.09; 95% CI, 0.83-1.43 for Del1518 +/- and -/-). These findings suggest that these two MDM2 promoter variants may not play a major role in the etiology of breast cancer.

Background: Accumulative evidence suggests that low folate intake is associated with increased risk of breast cancer. Polymorphisms in genes involved in folate metabolism may influence DNA methylation, nucleotide synthesis, and thus individual susceptibility to cancer. Thymidylate synthase (TYMS) is a key enzyme that participates in folate metabolism and catalyzes the conversion of dUMP to dTMP in the process of DNA synthesis. Two potentially functional polymorphisms [a 28-bp tandem repeat in the TYMS 5'-untranslated enhanced region (TSER) and a 6-bp deletion/insertion in the TYMS 3'-untranslated region (TS 3'-UTR)] were suggested to be correlated with alteration of thymidylate synthase expression and associated with cancer risk., Methods: To test the hypothesis that polymorphisms of the TYMS gene are associated with risk of breast cancer, we genotyped these two polymorphisms in a case-control study of 432 incident cases with invasive breast cancer and 473 cancer-free controls in a Chinese population., Results: We found that the distribution of TS3'-UTR (1494del6) genotype frequencies were significantly different between the cases and controls (P = 0.026). Compared with the TS3'-UTR del6/del6 wild-type genotype, a significantly reduced risk was associated with the ins6/ins6 homozygous variant genotype (adjusted OR = 0.58, 95% CI = 0.35-0.97) but not the del6/ins6 genotype (OR = 1.09, 95% CI = 0.82-1.46). Furthermore, breast cancer risks associated with the TS3'-UTR del6/del6 genotype were more evident in older women, postmenopausal subjects, individuals with a younger age at first-live birth and individuals with an older age at menarche. However, there was no evidence for an association between the TSER polymorphism and breast cancer risks., Conclusion: These findings suggest that the TS3'-UTR del6 polymorphism may play a role in the etiology of breast cancer. Further larger population-based studies as well as functional evaluation of the variants are warranted to confirm our findings.

Interleukin 1beta (IL-1beta) is a multifunctional cytokine that upregulates the inflammatory response, and participates in carcinogenesis, malignant transformation, tumor growth, invasion and metastasis. Two potentially functional polymorphisms (T-31C and C-511T) in the IL-1beta gene promoter were suggested to be correlated with alteration of IL-1beta expression and therefore may be associated with cancer risk. To test the hypothesis that these 2 polymorphisms are associated with risk of breast cancer, we performed a case-control study of 365 breast cancer cases, 270 patients with benign breast diseases (BBD) and 631 cancer-free controls in a Chinese population. Multivariate logistic regression analyses revealed that increased risk of breast cancer was associated with IL-1beta-31C variant genotypes [adjusted odds ratio (OR)=1.28 and 95% confidence interval (CI)=0.91-1.80 for -31CT and 1.72 (95% CI=1.16-2.54) for -31CC], compared with the -31TT genotype. Similarly, IL-1beta-511T variant genotypes were also associated with increased risk of breast cancer (adjusted OR=1.20, 95% CI=0.86-1.67 for -511CT and adjusted OR=1.74, 95% CI=1.18-2.56 for -511TT), compared with the -511CC genotype. Furthermore, cancer risks associated with IL-1betaT-31C variant genotypes were more evident in older women, postmenopausal women and individuals with a later menarche age. Interestingly, although we did not find significant associations of these 2 variants with cancer risk when compared with the BBD patients, a 1.27-fold (95% CI=1.01-1.60) increased risk was observed with the -31C-511T common haplotype. These findings indicate that these 2 IL-1beta promoter variants may contribute to risk of developing breast cancer in the Chinese population., (Copyright (c) 2005 Wiley-Liss, Inc.)

Adenosine diphosphate ribosyl transferase (ADPRT) and X-ray repair cross-complementing 1 (XRCC1) are two major base excision repair (BER) proteins and act cooperatively in the BER processes. Polymorphisms of ADPRT Val762Ala and XRCC1 Arg399Gln may alter their protein functions and BER activity, and were therefore hypothesized to be associated with breast cancer susceptibility. We examined the contributions of these two polymorphisms to breast cancer susceptibility in a case-control study of 302 breast cancer cases, 221 patients with benign breast disease (BBD) and 639 cancer-free controls in a Chinese population. We found that the variant genotypes of both ADPRT Val762Ala and XRCC1 Arg399Gln were not significantly associated with the risk of breast cancer (adjusted OR 0.87, 95% CI 0.64 to 1.19 for ADPRT Val/Ala + Ala/Ala; adjusted OR 0.82, 95% CI 0.61 to 1.11 for XRCC1 Arg/Gln + Gln/Gln; and adjusted OR 0.70, 95% CI 0.45 to 1.10 for these two combined variant genotypes. Similarly, we did not find any significant associations of these two genotypes with BBD risk. These findings suggest that the ADPRT Val762Ala and XRCC1 Arg399Gln polymorphisms may not play a role in the etiology of breast cancer.