Genetic polymorphisms of transforming growth factor-β1 and its receptors and colorectal cancer susceptibility: A population-based case-control study in China

Evaluating the predictive value of genetic risk score in colorectal cancer among Chinese Han population

Increasing single nucleotide polymorphisms (SNPs) have been identified to be associated with colorectal cancer (CRC). We aimed to investigate whether genetic risk scores (GRS) that aggregate information from multiple genetic variants can predict the risk of CRC in a Chinese population. Fifty candidate SNPs were selected to explore the associations with CRC in a discovery sample with 1002 CRC cases and 999 healthy controls. We modeled the significant SNPs identified by the case-control study as a multilocus weighted GRS and estimated the association of GRS with CRC. Furthermore, 300 pairs of cases and controls were included as a validation sample to confirm the finding. Area under the receiver operating characteristic curve (AUROC) was used to evaluate the predictive power of GRS in CRC. A total of seven SNPs were found to increase the risk of CRC, and two SNPs were found to be negatively associated with CRC in the discovery sample. Relative to participants with the lowest quartile of GRS, those with the highest quartile had a 2.64-fold (95% CI: 1.99-3.51) higher risk for CRC. For every 0.1 point of GRS increase, the risk of CRC increase by 11% (95% CI: 8-14%). AUROC for GRS alone were 0.59 (95% CI: 0.57-0.62) and 0.52 (95% CI: 0.46-0.58) in the discovery and validation sample, respectively. AUROC increased to 0.62 (95% CI: 0.59-0.64) and 0.71 (95% CI: 0.65-0.76) by combining environmental risk factors. Our findings support an association between GRS and risk of CRC, which provides evidence of improved prediction model for CRC in China.

Polymorphisms of a novel long non-coding RNA RP11-108K3.2 with colorectal cancer susceptibility and their effects on its expression

BACKGROUND

RP11-108K3.2 was recently identified as a novel long non-coding RNA (lncRNA) transcript, and several single nucleotide polymorphisms (SNPs) have been identified in its coding region. This study aimed to explore the associations of tagSNPs in RP11-108K3.2 with the risk of colorectal cancer and their effects on its expression.

METHODS

A total of 821 colorectal cancer cases and 857 healthy controls were enrolled into this two-stage case-control study. Demographic characteristics and lifestyle information were collected by a validated questionnaire. Six tagSNPs were genotyped by using Sequenom MassARRAY platform. A total of 71 additional colorectal cancer cases were recruited, of which the genotypes of potential polymorphisms and the RP11-108K3.2 expression levels were determined.

RESULTS

In the discovery set, only the rs2470151 C/T polymorphism was found to have a promising association with the risk of colorectal cancer, and this polymorphism was further replicated in the validation set with a significantly decreased risk of colorectal cancer (adjusted odds ratio 0.73; 95% confidence interval 0.55, 0.97). Combined discovery set and validation set together, this negative association was found both in the heterozygote codominant model and the dominant model. Furthermore, colorectal cancer patients carrying rs2470151 CT/TT genotypes had a marginally lower RNA expression of RP11-108K3.2 than those carrying the CC genotype. Stratified analyses showed the association between rs2470151 and the risk of colorectal cancer were influenced by family history of cancer, smoking, alcohol consumption, and tea drinking.

CONCLUSIONS

These findings suggest that RP11-108K3.2 rs2470151 had a significant association with the risk of colorectal cancer; this may help to predict the susceptibility of colorectal cancer in Chinese populations.

Association Between Head and Neck Cancers and Polymorphisms 869T/C, 509C/T, and 915G/C of the Transforming Growth Factor-β1 Gene: A Meta-Analysis of Case-Control Studies

Background

Worldwide, head and neck cancers are the eighth most common malignancy. Single nucleotide polymorphisms (SNPs) are associated with susceptibility to cancer and sensitivity to radiotherapy and chemotherapy. The inflammatory cytokine, transforming growth factor-β1 (TGF-β1), is involved in the progression of malignancy. This study aimed to systematically review the literature and undertake a meta-analysis of case-control studies on the association between 869T/C, 509C/T, and 915G/C polymorphisms of the TGF-β1 gene and head and neck cancers.

Material/Methods

The published literature in the English and Chinese languages were searched to identify relevant studies reporting TGF-β1 gene polymorphisms and head and neck cancer. The PubMed, Embase, Wanfang Data, and CNKI databases were searched. Data were extracted from eligible studies, and meta-analysis was performed using Stata version 12.0 software.

Results

Ten case-control studies were identified. There was a significant association between the 869T/C polymorphism of the TGF-β1 gene and susceptibility to head and neck cancer. Subgroup analysis showed that the 869T/C polymorphism was not significantly associated with the histological type of head and neck cancer, but was significantly associated with susceptibility to head and neck cancer in the Asian population. The 509C/T polymorphism of the TGF-β1 gene was not significantly associated with susceptibility to nasopharyngeal cancer (NPC), but the 915G/C polymorphism was associated with susceptibility to oral cancer.

Conclusions

Data from this meta-analysis showed that the 869T/C and 915G/C polymorphisms of the TGF-β1 gene might be associated with susceptibility to head and neck cancer.

Transforming growth factor-beta 1 polymorphisms and anti-tuberculosis drug-induced liver injury. Polymorphisms in TGFβ1 and its relationship with anti-tuberculosis drug-induced liver injury

AIM

There is evidence to suggest that transforming growth factor-beta 1 takes part in a series of physiological and pathological processes in the human body, including wound healing, tissue fibrosis and embryonic development. We hypothesized that polymorphisms in the transforming growth factor-beta 1 gene single nucleotide polymorphisms (SNPs) were associated with anti-tuberculosis drug-induced liver injury (ATLI).

METHODS

In a prospective study, 280 newly diagnosed tuberculosis patients were followed up for three months after initiating anti-tuberculosis therapy. Tag-SNPs of transforming growth factor-beta 1 were genotyped with the MassARRAY platform. The associations between SNPs and ATLI were analyzed by logistic regression analysis adjusting for confounding factors.

RESULTS

Of the 280 patients recruited in this study, 33 were excluded during the three months of follow-up, and 24 were diagnosed with ATLI and were considered as the ATLI group. The remaining 223 subjects without ATLI were considered as the non-ATLI group. After correction for potential confounding factors using a multivariate logistic regression analysis, we found that the frequencies of polymorphisms and haplotypes of transforming growth factor-beta 1 were similar in patients with ATLI and without ATLI.

CONCLUSION

The present results suggest that transforming growth factor-beta 1 polymorphisms do not play essential roles in the pathogenesis of ATLI in Chinese patients.

A novel SNP in promoter region of RP11-3N2.1 is associated with reduced risk of colorectal cancer

Single-nucleotide polymorphisms (SNPs) in the promoter region of long intergenic non-coding RNAs (lincRNAs) could play a regulatory role in its expression level and then get involved in colorectal cancer (CRC). Thus, we conducted a two-stage case-control study to investigate the associations of Tag SNPs within the promoter region of selected lincRNAs from microarray data with risk of CRC. A total of 320 cases and 319 controls were recruited in the test set to explore the associations between 16 SNPs with no deviations from Hardy-Weinberg equilibrium (HWE) and risk of CRC. Furthermore, 501 cases and 538 controls were included as the validation set to confirm the significant associations. RP11-3N2.1 rs13230517 polymorphism was found to be negatively associated with CRC in both test set (AA vs. GG, OR = 0.68, 95% CI = 0.48-0.96) and validation set (AA vs. GG, OR = 0.76, 95% CI = 0.59-0.98). Pooled analysis showed that individuals with GA/AA genotypes had a significantly decreased risk of CRC when compared with those carrying GG genotype (OR = 0.74, 95% CI = 0.60-0.90) in the combined set. The crossover analysis revealed that rs13230517 GA/AA carriers had a decreased risk of CRC than GG carriers among non-drinkers in both test and combined set. However, no gene-environment multiplicative interactions were found on risk of CRC. Our findings suggest that rs13230517 polymorphism might participate in the pathogenesis of CRC and have the potential to be a biomarker for predicting the risk of CRC.

Associations between novel genetic variants in the promoter region of MALAT1 and risk of colorectal cancer

The metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a well-known long non-coding RNA, is involved in pathogenesis and progress of multiple tumors. However, no study has been performed to investigate the relationship between the genetic variants in promoter region of MALAT1 and colorectal cancer risk. In this study, we conducted a two-stage case-control study to evaluate whether MALAT1 genetic variants were associated with colorectal cancer risk. We identified that a single nucleotide polymorphism (SNP) rs1194338 was significantly associated with the decreased colorectal cancer risk with an odds ratio (OR) of 0.70 [95% confidence interval (CI) = 0.49-0.99] in the combined stage. The subsequently stratified analyses showed that the protective effect of rs1194338 was more pronounced in several subgroups. Furthermore, gene expression profiling analysis revealed overexpression of MALAT1 mRNA in colorectal cancer tissue compared with normal controls. Confirmation studies with large sample size and further mechanistic investigations into the function of MALAT1 and its genetic variants are warranted to advance our understanding of their roles in colorectal carcinogenesis, and to aid in the development of novel and targeted therapeutic strategies.

Association of a novel genetic variant in RP11-650L12.2 with risk of colorectal cancer in Han Chinese population

BACKGROUND

This study aimed to investigate the associations of selected polymorphisms in RP11-650L12.2 with the risk of colorectal cancer (CRC) in a Chinese population.

METHODS

A total of 821 CRC cases (test set: 320, validation set: 501) and 857 healthy controls (test set: 319, validation set: 538) were enrolled in this study. Demographic characteristics and lifestyle information were collected by a validated questionnaire. A sample of 5ml venous blood was collected from each subject for DNA isolation, and the selected polymorphisms (rs144182521, rs514743, rs76071148, rs149941240) were genotyped by MassArray technique.

RESULTS

The rs149941240 polymorphism was significantly associated with the risk of CRC, with ORs of 1.50 (95% CI: 1.15-1.96) by co-dominant model and 1.45 (95% CI: 1.21-1.87) by dominant model in the test set, respectively. Correspondingly, the ORs were 1.48 (95% CI: 1.19-1.82) and 1.41 (95% CI: 1.15-1.73) in the validation set, respectively. The crossover analysis showed that non-smokers with the variant genotypes in rs149941240 had a significantly increased risk of CRC than those with wild genotype by dominant model in the validation set (OR 1.42, 95% CI 1.04-1.96). However, no gene-environment multiplicative interactions of rs149941240 with tobacco smoking were found on risk of CRC.

CONCLUSIONS

Our findings suggest that rs149941240 polymorphism was associated with the risk of CRC, and might contribute to the susceptibility to CRC. The effects of this polymorphism should be validated in a larger sample and require further mechanistic investigations to determine the nature of its influence on CRC.

Association between Int7G24A rs334354 polymorphism and cancer risk: a meta-analysis of case-control studies

Accumulating evidences have suggested the potential association between Int7G24A (rs334354) polymorphism and cancer risk. However, results from epidemiological studies are controversial. We thus conducted this meta-analysis to clarify the association. Relevant studies were identified on electronic databases according to the inclusion criteria. A total of 13 case-control studies containing 4092 cases and 5909 controls were included in our meta-analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the association. The results of the overall population had suggested that Int7G24A polymorphism had an increased risk for cancer, reaching significant levels in the 2 genetic models (allele model, OR = 1.25, 95% CI 1.09-1.42, P = 0.001; dominant model, OR = 1.24, 95% CI 1.06-1.46, P < 0.008). Besides, significant association was found among Asian population (allele model, OR = 1.27, 95% CI 1.11-1.45, P < 0.001; dominant model, OR = 1.28, 95% CI 1.11-1.49, P < 0.001), whereas there was non-significant relationship detected among Caucasian population (allele model, OR = 1.08, 95% CI 0.92-1.26, P = 0.352; dominant model, OR = 1.05, 95% CI 0.87-1.26, P = 0.639). The present meta-analysis had suggested that Int7G24A polymorphism of gene TGFBR1 involved in the transforming growth factor beta (TGF-β) signaling pathway had a significantly increased risk for cancer development.

RPSA gene mutants associated with risk of colorectal cancer among the chinese population

The primary aim of this study was to evaluate the relationship of single nucleotide polymorphisms (SNPs) in ribosomal protein SA (RPSA) gene with colorectal cancer (CRC). A case-control study including 388 controls and 387 patients with CRC was conducted in a Chinese population. Information about socio-demography and living behavior factors was collected by a structured questionnaire. Three SNPs (rs2133579, rs2269349, rs7641291) in RPSA gene were genotyped by Illumina SnapShot method. Multiple logistic regression models were used for assessing the joint effects between tea consumption and SNPs on CRC. The subjects with rs2269349 CC genotype had a decreased risk for CRC (OR=0.60; 95%CI = 0.37-0.99), compared with TT/CT genotype after adjustment for covariates. A similar association of rs2269349 with rectal cancer was observed (OR=0.49; 95%CI=0.24-1.00). Further analyses indicated that this SNP could modify the protective effect of tea drinking on CRC. Among the subjects with rs2269349 TT/CT or rs2133579 AA/GA, there was a marginal significantly lower risk of CRC (OR and 95%CI: 0.63 and 0.39-1.01 for rs2269349; 0.64 and 0.40-1.02 for rs2133579) in tea-drinking subjects in comparison to non-tea-drinking subjects. Mutants in the RPSA gene might be associated with genetic susceptibility to CRC and influence the protective effect of tea consumption in the Chinese population.

A functional polymorphism C-509T in TGFβ-1 promoter contributes to susceptibility and prognosis of lone atrial fibrillation in Chinese population

Transforming growth factor-β1 (TGF-β1) is an important mediator of atrial fibrosis and atrial fibrillation (AF). But the involved genetic mechanism is unknown. Herein, the TGF-β1 C-509 T polymorphism (rs1800469) was genotyped in a case-control study of 840 patients and 845 controls in Chinese population to explore the association between the polymorphism and susceptibility and prognosis of lone AF. As a result, the CT and/or TT genotypes had an increased lone AF risk [adjusted odds ratio (OR) = 1.50 for CT, OR = 3.72 for TT, and OR = 2.15 for CT/TT], compared with the TGF-β1CC genotype. Moreover, patients carrying CT/TT genotypes showed a higher possibility of AF recurrence after catheter ablation, compared with patients carrying CC genotype. In a genotype-phenotype correlation analysis using 24 normal left atrial appendage samples, increasing gradients of atrial TGF-β1 expression levels positively correlated with atrial collagen volume fraction were identified in samples with CC, CT and TT genotypes. The in vitro luciferase assays also showed a higher luciferase activity of the -509 T allele than that of the -509 C allele. In conclusion, the TGF-β1 C-509 T polymorphism is involved in the etiology of lone AF and thus may be a marker for genetic susceptibility to lone AF and predicting prognosis after catheter ablation in Chinese populations. Therefore, we provide new information about treatment strategies and our understanding of TGF-β1 in AF.

The association of phosphatase and tensin homolog deleted on chromosome 10 polymorphisms and lifestyle habits with colorectal cancer risk in a Chinese population

The PI3K signaling pathway plays an important role in the development of colorectal cancer (CRC) and other neoplasm. Somatic phosphatase and tensin homolog deleted on chromosome 10 (PTEN) mutations and deletions or epigenetic silencing have been observed in multiple tumor types including CRC. To assess the association of PTEN polymorphisms and lifestyle habits with CRC risk in Chinese population, we carried out a case-control study which included 545 cases and 522 controls. In the present study, we genotyped eight single-nucleotide polymorphisms (SNPs) in PTEN and found that rs11202607 was associated with increased CRC risk (odds ratio (OR) = 1.40, 95 % confidence interval (CI) = 1.04-1.90). Stratification analysis by lifestyle habits showed a stronger association between rs11202607 and CRC risk among never tea drinkers than that among tea-drinkers (OR = 2.04, 95 % CI 1.29-3.22), and significant additive interaction between rs10490920 and tea drinking status was observed. Our study provided the evidence of an association between PTEN polymorphisms and the risk of CRC and significant additive interaction between PTEN polymorphism and tea drinking. Studies with larger sample size and further investigations into the mechanism are warranted to clarify the role of PTEN in colorectal carcinogenesis and the association between PTEN genetic variations, environment exposure, and CRC risk.

TheTGFB1 functional polymorphism rs1800469 and susceptibility to atrial fibrillation in two Chinese Han populations

Transforming growth factor-β1 (TGF-β1) is related to the degree of atrial fibrosis and plays critical roles in the induction and perpetuation of atrial fibrillation (AF). To investigate the association of the common promoter polymorphism rs1800469 in the TGF-β1 gene (TGFB1) with the risk of AF in Chinese Han population, we carried out a case-control study of two hospital-based independent populations: Southeast Chinese population (581 patients with AF and 723 controls), and Northeast Chinese population (308 AF patients and 292 controls). Two hundred and seventy-eight cases of AF were lone AF and 334 cases of AF were diagnosed as paroxysmal AF. In both populations, AF patients had larger left atrial diameters than the controls did. The rs1800469 genotypes in the TGFB1 gene were determined by polymerase chain reaction-restriction fragment length polymorphism. The genotype and allele frequencies of rs1800469 were not different between AF patients and controls of the Southeast Chinese population, Northeast Chinese population, and total Study Population. After adjustment for age, sex, hypertension and LAD, there was no association between the rs1800469 polymorphism and the risk of AF under the dominant, recessive and additive genetic models. Similar results were obtained from subanalysis of the lone and paroxymal AF subgroups. Our results do not support the role of the TGFB1 rs1800469 functional gene variant in the development of AF in the Chinese Han population.

Association of CASP9, CASP10 gene polymorphisms and tea drinking with colorectal cancer risk in the Han Chinese population

The initiators caspase-9 (CASP9) and caspase-10 (CASP10) are two key controllers of apoptosis and play important roles in carcinogenesis. This study aims to explore the association between CASPs gene polymorphisms and colorectal cancer (CRC) susceptibility in a population-based study. A two-stage designed population-based case-control study was carried out, including a testing set with 300 cases and 296 controls and a validation set with 206 cases and 845 controls. A total of eight tag selected single nucleotide polymorphisms (SNPs) in CASP9 and CASP10 were chosen based on HapMap and the National Center of Biotechnology Information (NCBI) datasets and genotyped by restriction fragment length polymorphism (RFLP) assay. Multivariate logistic regression models were applied to evaluate the association of SNPs with CRC risk. In the first stage, from eight tag SNPs, three polymorphisms rs4646077 (odds ratio (OR)(AA+AG): 0.654, 95% confidence interval (CI): 0.406-1.055; P=0.082), rs4233532 (OR(CC): 1.667, 95% CI: 0.967-2.876; OR(CT): 1.435, 95% CI: 0.998-2.063; P=0.077), and rs2881930 (OR(CC): 0.263, 95% CI: 0.095-0.728, P=0.036) showed possible association with CRC risk. However, none of the three SNPs, rs4646077 (OR(AA+AG): 1.233, 95% CI: 0.903-1.683), rs4233532 (OR(CC): 0.892, 95% CI: 0.640-1.243; OR(CT): 1.134, 95% CI: 0.897-1.433), and rs2881930 (OR(CC): 1.096, 95% CI: 0.620-1.938; OR(CT): 1.009, 95% CI: 0.801-1.271), remained significant with CRC risk in the validation set, even after stratification for different tumor locations (colon or rectum). In addition, never tea drinking was associated with a significantly increased risk of CRC in testing set together with validation set (OR: 1.755, 95% CI: 1.319-2.334). Our results found that polymorphisms of CASP9 and CASP10 genes may not contribute to CRC risk in Chinese population and thereby the large-scale case-control studies might be in consideration. In addition, tea drinking was a protective factor for CRC.

Transforming growth factor beta-1 C-509T polymorphism and cancer risk: a meta-analysis of 55 case-control studies

AIM

To investigate the association of transforming growth factor-beta 1 (TGF-β1) C-509T polymorphism and susceptibility to cancer by means of meta-analysis.

METHODS

An extensive search was performed to identify eligible case-control studies investigating such a link. The strength of the association between TGF-β1 C-509T polymorphism and cancer risk was assessed by pooled odds ratios (ORs) and 95%confidence intervals (95%CIs) in fixed or random effects models.

RESULTS

55 published case-control studies with a total number of 21,639 cases and 28,460 controls were included. Overall, there was no association between TGF-β1 C-509T and cancer risk in all genetic comparison models (TT vs. CC: OR=1.01, 95%CI=0.89-1.15; T vs. C: OR=1.01, 95%CI=0.94-1.07). However, a stratified analysis by cancer type indicated -509 T allele was significantly associated with decreased risk of colorectal cancer (CRC) (TT vs. CT/CC: OR=0.85, 95%CI=0.76-0.95), especially for Caucasians (TT vs. CT/CC: OR=0.83, 95%CI=0.71-0.98) and for population-based studies (TT vs. CT/CC: OR=0.78, 95%CI=0.68- 0.89).

CONCLUSION

This meta-analysis suggested that TGF-β1 C-509T polymorphism might contribute to a decreased risk on colorectal cancer susceptibility, especially for Caucasians.

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

AIM

Published 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.

METHODS

Meta-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.

RESULTS

We 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).

CONCLUSIONS

The 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.

Correlation between TGF-β1-509 C>T polymorphism and risk of digestive tract cancer in a meta-analysis for 21,196 participants

The association between transforming growth factor β1 (TGF-β1)-509 C>T and risk of digestive tract cancer (DTC) remained uncertain as previous studies reported conflicting results. The aim of this study was to assess the association by using a meta-analysis. The databases of MEDLINE, EMBASE and WANGFANG (Chinese database) were retrieved, and latest update was on 2nd February, 2012. Pooled odds ratio and 95% confidence interval (OR and 95% CI) were calculated by using a fixed- or random-effect model. Ultimately, twenty nine case-control studies with 8664 cases and 12,532 controls were included in this meta-analysis. Overall, there was no association between TGF-β1-509 C>T and risk of DTC in all genetic comparison models (OR and 95% CI: 0.96 and 0.81-1.15 for TT vs. CC, 0.98 and 0.91-1.05 for T carriers vs. C carriers). When subgroup analyses were conducted according to ethnicity, types of cancer and sample size, T allele was significantly associated with decreased risk of DTC for Caucasians and for large sample-sized studies, and was associated with decreased risk of colorectal cancer (OR and 95% CI for TT vs. CC: 0.82 and 0.70-0.97 for Caucasians, 0.80 and 0.68-0.98 for large sample-sized studies, 0.78 and 0.62-0.97 for colorectal cancer). This study indicated that TGF-β1-509 C>T polymorphism was probably associated with risk of DTC, especially for Caucasians. Because of modest limitation, our findings should be confirmed by future studies.

Association between TGFBR1 polymorphisms and cancer risk: a meta-analysis of 35 case-control studies

Background

Numerous epidemiological studies have evaluated the association between TGFBR1 polymorphisms and the risk of cancer, however, the results remain inconclusive. To derive a more precise estimation of the relation, we conducted a comprehensive meta-analysis of all available case-control studies relating the TGFBR1*6A and IVS7+24G>A polymorphisms of the TGFBR1 gene to the risk of cancer.

Methods

Eligible studies were identified by search of electronic databases. Overall and subgroup analyses were performed. Odds ratio (OR) and 95% confidence interval (CI) were applied to assess the associations between TGFBR1*6A and IVS7+24G>A polymorphisms and cancer risk.

Results

A total of 35 studies were identified, 32 with 19,767 cases and 18,516 controls for TGFBR1*6A polymorphism and 12 with 4,195 cases and 4,383 controls for IVS7+24G>A polymorphism. For TGFBR1*6A, significantly elevated cancer risk was found in all genetic models (dominant OR = 1.11, 95% CI = 1.04∼1.18; recessive: OR = 1.36, 95% CI = 1.11∼1.66; additive: OR = 1.13, 95% CI = 1.05∼1.20). In subgroup analysis based on cancer type, increased cancer risk was found in ovarian and breast cancer. For IVS7+24G>A, significant correlation with overall cancer risk (dominant: OR = 1.39, 95% CI = 1.15∼1.67; recessive: OR = 2.23, 95% CI = 1.26∼3.92; additive: OR = 1.43, 95% CI = 1.14∼1.80) was found, especially in Asian population. In the subgroup analysis stratified by cancer type, significant association was found in breast and colorectal cancer.

Conclusions

Our investigations demonstrate that TGFBR1*6A and IVS7+24G>A polymorphisms of TGFBR1 are associated with the susceptibility of cancer, and further functional research should be performed to explain the inconsistent results in different ethnicities and cancer types.

The joint association of REST and NFKB1 polymorphisms on the risk of colorectal cancer

Due to the high morbidity and mortality of colorectal cancer (CRC), this study aims to determine the joint association of RE-1-silencing transcription factor (REST) and nuclear factor-κB 1 (NFKB1) genes with CRC in a population-based study. A well-matched case-control study including 390 controls and 388 patients with CRC was enrolled in China. The selected single nucleotide polymorphisms (SNPs) in the REST and NFKB1 genes were genotyped by Illumina SnapShot Chip. After adjustment for important covariates, the associations of SNPs and joint association of REST and NFKB1 with CRC were evaluated by multiple logistic regression models. The subjects with the rs2228991 AA genotype of the REST gene had a decreased risk for CRC (OR = 0.38; 95%CI: 0.19-0.74), compared with the GG genotype. There were no significant associations between three SNPs in the NFKB1 gene, their haplotype and CRC risk. However, a significant combined effect of rs3774959 and rs3774964 in the NFKB1 gene with rs2228991 in the REST gene on CRC risk was observed. In conclusion, the present study found that mutation in the REST gene rather than the NFKB1 gene was associated with the risk of CRC. Furthermore, significant REST-NFKB1 joint association was observed for CRC, colon cancer and rectal cancer risk.

Decreased levels of active SMAD2 correlate with poor prognosis in gastric cancer

BACKGROUND

TGF-β plays a dual role in the progression of human cancer. During the early stages of carcinogenesis, TGF-β functions as a tumor suppressor. During the late stages of tumor development, however, TGF-β can promote tumor growth and metastasis. A shift in Smad2/3 phosphorylation from the carboxy terminus to linker sites is a key event determining biological function of TGF-β in colorectal and hepatocellular carcinoma. In the present study, we investigated the potential role of differential Smad2/3 phosphorylation in gastric adenocarcinoma.

METHODOLOGY

Immunohistochemical staining with anti-P-Smad2/3C and P-Smad2/3L antibodies was performed on 130 paraffin-embedded gastric adenocarcinoma specimens. The relationship between P-Smad2/3C and P-Smad2/3L immunohistochemical score and clinicopathologic characteristics of patients was analyzed. Real time PCR was used to measure mRNA expression of Smad2 and Smad3 in cancer and surrounding non-tumor tissue.

PRINCIPAL FINDINGS

No significant P-Smad2L and/or P-Smad3L positive staining was detected in the majority of specimens (positive staining in 18/130 samples). Positive P-Smad2/3L staining was not associated with a decrease in carboxyterminal phosphorylation staining. Loss of P-Smad2C remarkably correlated with depth of tumor infiltration and poor differentiation of cancer cells in patients with gastric cancer. No correlation was detectable between P-Smad3C and clinicopathologic characteristics of gastric adenocarcinoma. However, co-staining analysis revealed that P-Smad3C co-localised with α-SMA and collagen I in gastric cancer cells, indicating a potential link between P-Smad3C and epithelial-to-mesenchymal transition of cancer. Real time PCR demonstrated reduced mRNA expression of Smad2 in gastric cancer when compared with surrounding non-tumor tissue in 15/16 patients.

CONCLUSIONS

Loss of P-Smad2C tightly correlated with cancer invasion and poor differentiation in gastric cancer. Contrary to colorectal and hepatocellular carcinoma, canonical carboxy-terminal phosphorylation, but not linker phosphorylation, of Smad2 is critical for gastric cancer.

Meta-analyses of the associations between four common TGF-β1 genetic polymorphisms and risk of colorectal tumor

The associations between four common genetic polymorphisms of transforming growth factor-β1 (TGF-β1 -509 C > T, +869 T > C, +915 G > C, and -800 G > A) and risk of colorectal tumor (including adenoma and cancer) have been widely studied. To date, no conclusions could be available because of controversial results reported. Thus, we conducted a meta-analysis to further assess the associations. We searched the databases of Medline, Embase, and Wangfang to identify eligible studies, and latest update was on January 1, 2012. Odds ratio (OR) and 95% confidence interval (95%CI) were calculated to present the associations. Our meta-analysis indicated that TGF-β1 -509 C > T, +869 T > C, +915 G > C, and -800 G > A were not associated with risk of colorectal adenoma (OR = 0.89 for C carriers vs. TT for -509 C > T, 1.03 for C carriers vs. TT for +869 T > C, 1.09 for C carriers vs. GG for +915 G > C, and 1.19 for A carriers vs. GG for 800 G > A). However, C allele of TGF-β1 -509 C > T and A allele of -800 G > A were associated with increased risk of colorectal cancer (CRC), and OR (95%CI) was 1.23 (0.99-1.52) for CC vs. TT for -509 C > T and 6.64 (3.46-12.72) for A carriers vs. GG. The positive association between -509 C allele and risk of CRC was more obvious when subgroup analyses were conducted for population-based and large sample-sized studies as well as Caucasians. In contrast, we did not observed any associations between TGF-β1 +869 T > C, +915 G > C, and risk of CRC. This study indicated that C allele of TGF-β1-509 C > T and A allele of -800 G > A might contribute to the increased risk of CRC, and could be used as two of genetic marks for screening individuals at high risk of CRC. Because of modest limitation, large sample-sized studies were required to confirm the findings.

DNA repair genes XPC, XPG polymorphisms: relation to the risk of colorectal carcinoma and therapeutic outcome with Oxaliplatin-based adjuvant chemotherapy

Xeroderma pigmentosum complementation group C and G (XPC, XPG) play important roles in DNA damage repairing machinery. Genetic variations in the XPC and XPG may be associated with increased risk for colorectal carcinoma (CRC). In this study, we evaluated the relation between the XPC Lys939Gln, XPG Asp1104His polymorphisms, and CRC susceptibility in a population-based case-control study, which included 1,028 CRC cases and 1,085 controls. Compared with the corresponding wild genotypes, we found that individuals with at least one copy of the XPC Lys939Gln (AC or CC genotype) and XPG Asp1104His (GC or CC genotype) had an increased risk for CRC. In addition, the variant genotypes of the XPC Lys939Gln AC/CC (P = 0.027) or XPG Asp1104His GC/CC (P = 0.003) reduced the elevation of preoperative carcinoembryonic antigen (CEA) level. Moreover a significantly longer progression-free survival (PFS) after Oxaliplatin-based adjuvant chemotherapy was observed in patients with XPG Asp1104His wide-type GG genotype (n = 432, Log-rank test: P = 0.033). Cox proportional hazards analyses demonstrated that variant genotypes of XPG Asp1104His [hazard ratio (HR) = 1.692, 95% confidence interval (95%CI): 1.202-2.383, P = 0.003] as well as pathology grade (HR = 2.545, 95%CI: 2.139-3.030, P < 0.001), and lymph node metastases (HR = 1.851, 95%CI: 1.306-2.625, P < 0.001) were predictive of shorter PFS for the CRC patients with Oxaliplatin-based adjuvant chemotherapy. In conclusion, the current data suggested that XPC Lys939Gln and XPG Asp1104His polymorphisms might contribute to the identification of patients with increased risk for CRC.

Associations of lifestyle-related factors, hsa-miR-149 and hsa-miR-605 gene polymorphisms with gastrointestinal cancer risk

To explore the associations of SNPs within hsa-miR-605 (rs2043556) and hsa-miR-149 (rs2292832) and lifestyle-related factors with gastrointestinal cancer, a case-control study including 762 cases and 757 controls was conducted. Marginally significant associations were found both for hsa-miR-149 rs2292832 with gastric cancer risk (TC + CC vs. TT, OR = 0.68, 95% CI: 0.44-1.04) and for hsa-miR-605 rs2043556 with colorectal cancer risk (AG + GG vs. AA, OR = 0.70, 95% CI: 0.48-1.02) in males. Tea drinking showed a protective effect on gastric cancer risk (OR = 0.28, 95% CI: 0.13-0.60), while smoke inhalation increased the risk of gastric cancer (OR = 1.94, 95% CI: 1.08-3.47). Irritability was found to be a risk factor for both colorectal cancer (OR = 1.61, 95% CI: 1.02-2.53) and gastric cancer (OR = 1.96, 95% CI: 1.17-3.29). Among those that engaged in smoke inhalation, miR-149 CT/CC and miR-605 AG/GG genotype carriers had increased susceptibilities to colorectal cancer (OR = 1.90, 95% CI: 1.11-3.25) and gastric cancer (OR = 1.87, 95% CI: 1.03-3.42), respectively. Among the tea drinkers, there exists a marginally protective effect of miR-605 AG/GG genotypes on colorectal cancer incidence (OR = 0.71, 95% CI: 0.47-1.06) and a significantly protective effect of miR-149 CT/CC on gastric cancer incidence (OR = 0.47, 95% CI: 0.29-0.77). The SNPs of rs2292832 and rs2043556 might be able to modify the susceptibility to male gastric and colorectal cancers, respectively. Tea drinking is a protective factor, while smoke inhalation is a risk factor for gastric cancer, and they might have the potential to modify the associations between miR-149 and miR-605 polymorphisms with gastrointestinal cancer risk. In addition, irritability was shown to be a risk factor for both gastric and colorectal cancers.

Genetic polymorphism at codon 10 of the transforming growth factor-β1 gene in patients with alcoholic liver cirrhosis

Background/Aims

Transforming growth factor beta1 (TGF-β1) is a key cytokine in the production of extracellular matrix. A genetic polymorphism at codon 10 of the TGF-β1 gene is associated with liver fibrosis. We investigated the effect of genetic polymorphisms at codon 10 on the development of alcoholic liver cirrhosis (ALC).

Methods

In total, 119 controls and 182 patients with ALC, were enrolled in the study. Clinical and laboratory data including total lifetime alcohol intake were collected at enrollment. The genotype at codon 10 was determined for each patient by single-strand conformation polymorphism.

Results

There were three types of genetic polymorphism at codon 10: homozygous proline (P/P), heterozygous proline/leucine (P/L), and homozygous leucine (L/L). Among the controls, the proportions of P/P, P/L, and L/L were 26.1%, 44.5%, and 29.4%, respectively in the ALC group, these proportions were 23.1%, 43.4%, and 33.5%, respectively. The genotype distribution did not differ between the controls and the ALC group. In the ALC group, age, total lifetime alcohol intake, and distribution of Child-Pugh class did not differ with the genotype. Of the male patients with ALC (n=164), the proportions of P/P, P/L, and L/L were 20.1%, 44.5%, and 35.4%, respectively the genotype distribution did not differ between the male controls and the male ALC patients.

Conclusions

The genotype at codon 10 in TGF-β1 does not appear to influence the development of ALC. Further study is needed to investigate other genetic factors that influence the development of ALC in patients with chronic alcohol intake.

A functional polymorphism of TGFBR2 is associated with risk of breast cancer with ER(+), PR(+), ER(+)PR(+) and HER2(-) expression in women

Little is known about the correlation between TGFBR2 G-875A and breast cancer risk. Moreover, the associations of the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) in breast cancer tissues with the TGFB1 C-509T, T+29C and TGFBR2 G-875A polymorphisms remain to be determined. In this study, we genotyped for TGFB1 C-509T, T+29C and TGFBR2 G-875A in fresh surgically resected tissues (n=82) and archived paraffin-embedded specimens (n=88) from 170 patients with breast cancer, as well as peripheral blood samples from 178 cancer-free female individuals. Evaluation of ER, PR and HER2 expression was performed using immunohistochemical staining. Logistic regression analysis was carried out to determine the risk of breast cancer by calculating the odds ratios (ORs) and their 95% confidence intervals (CIs). As a result, no difference was observed in the TGFB1 C-509T, T+29C genotype and allele frequencies between patients and controls. However, the frequency of the TGFBR2 -875A allele was marginally higher in cancer-free female individuals than that of women with breast cancer (24.2 vs. 17.9%, P=0.05). Notably, when stratification was performed by ER, PR and HER2 expression, the TGFBR2 -875A allele was found to correlate significantly to a decreased risk of breast cancer with ER(+) (OR=0.57, 95% CI 0.35-0.92), PR(+) (OR=0.54, 95% CI 0.34-0.88), ER(+)PR(+) (OR=0.55, 95% CI 0.33-0.92) and HER2(-) (OR=0.55, 95% CI 0.34-0.88) under a dominant genetic model. In conclusion, this is the first study to suggest that the TGFBR2 -875A allele modifies predisposition to breast cancer with an expression of ER(+), PR(+), ER(+)PR(+) and HER2(-).

Association of TGF-beta1 gene polymorphisms in exon1 and blood levels with essential hypertension

AIMS

Based on a case-control study, we investigated the relationship between +869T/C and +915G/C gene polymorphisms in transforming growth factor-beta1 (TGF-beta1), protein levels and essential hypertension (EH) in the Kazakh and Han Chinese populations selected from the Boertonggu countryside of Shawan region in the Xinjiang Uygur Autonomous Region of China (n=1600). The polymorphisms of TGF-beta1 and the blood levels were detected using polymerase chain reaction-restriction fragment length polymorphism assays and sandwich ELISA, respectively.

MAJOR FINDINGS

An association was found between +869C-allele with higher risk of EH in these two populations. We also found that the CG haplotype of the two polymorphisms was associated with EH in the Kazakh EH patients. The levels of TGF-beta(1) in the blood were positively correlated with diastolic blood pressure both in the Kazakh and Han EH patients. Levels of the TGF-beta1 protein in the Kazakh EH patients were significantly higher than those in the Han EH patients.

PRINCIPAL CONCLUSION

These results suggest that the TGF-beta1 +869 C allele is potentially a genetic factor of EH in these two ethnicities, the CG haplotype can be a genetic marker of EH in the Kazakh Chinese and the high concentration of TGF-beta1 is possibly associated with EH, especially in the Kazakh population.

The association of XPC polymorphisms and tea drinking with colorectal cancer risk in a Chinese population

The xeroderma pigmentosum complementation group C (XPC) is responsible for removal of bulky helix-distorting DNA lesions. Several polymorphisms of XPC gene may modulate the colorectal cancer (CRC) susceptibility. We assessed the association of XPC Lys939Gln (A/C), Ala499Val (C/T), and PAT (-/+) polymorphisms with CRC risk in a population-based case-control study which included 421 CRC patients and 845 controls. For Lys939Gln, the CC genotype was associated with a significantly increased risk of CRC (odds ratio (OR)=1.5; 95% confidence interval (CI)=1.0-2.2) compared with the AA genotype. The subjects with PAT +/+ genotype had a significantly increased risk of CRC (OR=1.5; 95% CI=1.0-2.3), compared with those with PAT-/- genotype. Though no significant association between Ala499Val and CRC risk was observed, we found that individuals carrying the CT+TT genotypes showed a significantly decreased risk of rectal cancer (OR=0.7; 95% CI=0.5-1.0). Additionally, the haplotype C+C was associated with a significantly increased CRC risk (OR=1.3; 95% CI=1.0-1.6), compared with the most common haplotype A-T. Further, individuals with four or more risk alleles exhibited a significantly increased risk of CRC (OR=1.4; 95% CI=1.0-2.0), with a significant gene-dosage effect (P for trend=0.038). Besides, never tea drinking was associated with a significantly increased risk of CRC (OR=2.3; 95% CI=1.7-3.3). Our results suggest that the XPC polymorphisms may modulate CRC susceptibility independently or jointly, and tea drinking has a protective effect on CRC.

Association of selected polymorphisms of CCND1, p21, and caspase8 with colorectal cancer risk

It has been well elucidated that the signal transduction of cell-cycle control pathway and apoptosis pathway plays an important role in the normal growth and differentiation of organisms. To test the hypothesis that mutants of key genes involved in cell-cycle regulation and apoptosis might contribute to the increased risk of colorectal cancer (CRC), a population-based case-control study was carried out in Jiashan County, Zhejiang Province. The study population was composed of 373 CRC cases and 838 controls. Five genetic variants including CCND1 G870A, p21 codon31 C/A, p21 3'UTR C/T, caspase8 IVS12-19G/A, and caspase8 6n del/ins were genotyped. The associations of the polymorphisms with CRC were estimated by logistical regression model after adjustment for the important covariates. The interactive effect among the five selected genetic polymorphisms on CRC was explored by multifactor dimensionality reduction (MDR) software. The significant association between five single-nucleotide polymorphisms (SNPs) and CRC risk was not observed, respectively. However, caspase8 del/del showed a marginally significant association with the increased risk of rectum cancer [adjusted odds ratio (OR) (95% confidence interval, CI) = 1.92 (0.97-3.79); P = 0.06]. Furthermore, the MDR analysis indicated that the best interactive model for CRC included three factors-CCND1 G870A, caspase8 IVS12-19G/A, and caspase8 6 n del/ins-with 53.44% testing balanced accuracy and 10/10 cross-validation consistency, but the model was no longer significant after the 1000 times permutation test (P = 0.25). Our findings suggest that the selected polymorphisms of p21, CCND1, and caspase8 may not contribute to the risk of colorectal cancer.

TGFbeta1 T29C polymorphism and cancer risk: a meta-analysis based on 40 case-control studies

Transforming growth factor-beta1 (TGFbeta1) plays a significant role in regulating cellular proliferation and apoptosis. The TGFbeta1 T29C polymorphism reportedly affects cancer risk, but pertinent studies offer conflicting results. We therefore performed a meta-analysis based on 40 studies from 32 publications, assessing the strength of the association using odds ratios with 95% confidence intervals. Overall, no evidence has indicated that individuals carrying CC or CT genotypes had significantly increased cancer risks, compared with TT genotype carriers [CC vs. TT: odds ratio (OR)=1.10, 95% confidence interval (95% CI)=1.00-1.21, P=0.06; CT vs. TT: OR=1.07, 95% CI=0.99-1.16, P=0.09). However, stratified analysis by cancer type and ethnicity indicated a significantly increased risk of prostate cancer (CT vs. TT: OR=1.28, 95% CI=1.01-1.61, P=0.04) and cancer in those of Asian descent (CC vs. TT: OR=1.26, 95% CI=1.03-1.53, P=0.02; CT vs. TT: OR=1.20, 95% CI=1.01-1.43, P=0.04). This association was also observed in the dominant model for prostate cancer. Although not all bias could be eliminated, this meta-analysis suggested that TGFbeta1 29C was a low-penetrant risk factor for prostate cancer and cancer in Asians. A larger single study is still required to evaluate any association with other types of cancer or in other populations.

TGFB1 509 C/T polymorphism and colorectal cancer risk: a meta-analysis

Transforming growth factor β (TGF-β) is a cytokine. The TGF-β signaling pathway plays an important role in controlling cell proliferation and differentiation involved in colorectal carcinogenesis. In mammalian cells, TGFB1 is the most abundant subtype of TGF-β. The 509 C/T polymorphism in TGFB1 has been implicated in colorectal cancer risk. However, published data remain conflicting. To derive a more precise estimation of the relationship, a meta-analysis of 994 cases and 2,335 controls from five published case-control studies was performed. Overall, significantly increased colorectal cancer risks were found for CC versus TT (OR=1.62; 95% CI: 1.30-2.02; Pheterogeneity=0.118), TC+CC versus TT (OR=1.30; 95% CI: 1.08-1.58; Pheterogeneity=0.259) and CC versus TC+TT (OR=1.48; 95% CI: 1.26-1.75; Pheterogeneity=0.244). In the subgroup analysis by ethnicity, significantly increased risks were also found among Asians for CC versus TT (OR=1.77; 95% CI: 1.40-2.24; Pheterogeneity=0.519), TC+CC versus TT (OR=1.38; 95% CI: 1.13-1.68; Pheterogeneity=0.679) and CC versus TC+TT (OR=1.58; 95% CI: 1.31-1.89; Pheterogeneity=0.340). However, no significant associations were found among Europeans for all genetic models. This meta-analysis showed that TGFB1 509 C allele is a risk factor for developing colorectal cancer in Asians.