Contribution of transforming growth factor α polymorphisms to nonsyndromic orofacial clefts: a HuGE review and meta-analysis

TGFA expression is associated with poor prognosis and promotes the development of cervical cancer

Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) are the second most common cancers in women aged 20-39. While HPV screening can help with early detection of cervical cancer, many patients are already in the medium to late stages when they are identified. As a result, searching for novel biomarkers to predict CESC prognosis and propose molecular treatment targets is critical. TGFA is a polypeptide growth factor with a high affinity for the epidermal growth factor receptor. Several studies have shown that TGFA can improve cancer growth and progression, but data on its impact on the occurrence and advancement of CESC is limited. In this study, we used clinical data analysis and bioinformatics techniques to explore the relationship between TGFA and CESC. The results showed that TGFA was highly expressed in cervical cancer tissues and cells. TGFA knockdown can inhibit the proliferation, migration and invasion of cervical cancer cells. In addition, after TGFA knockout, the expression of IL family and MMP family proteins in CESC cell lines was significantly reduced. In conclusion, TGFA plays an important role in the occurrence and development of cervical cancer. Therefore, TGFA may become a new target for cervical cancer treatment.

Genetic markers for non-syndromic orofacial clefts in populations of European ancestry: a meta-analysis

To date, the involvement of various genetic markers in the aetiopathogenesis of non-syndromic orofacial cleft (nsOFC) has been extensively studied. In the present study, we focused on studies performed on populations of European ancestry to systematically review the available literature to define relevant genetic risk factors for nsOFC. Eligible studies were obtained by searching Ovid Medline and Ovid Embase. We gathered the genetic markers from population-based case–control studies on nsOFC, and conducted meta-analysis on the repeatedly reported markers. Whenever possible, we performed stratified analysis based on different nsOFC phenotypes, using allelic, dominant, recessive and overdominant genetic models. Effect sizes were expressed as pooled odds ratios (ORs) with 95% confidence intervals (CIs), and p ≤ 0.05 were considered statistically significant. A total of 84 studies were eligible for this systematic review, with > 700 markers included. Of these, 43 studies were included in the meta-analysis. We analysed 47 genetic variants in 30 genes/loci, which resulted in 226 forest plots. There were statistically significant associations between at least one of the nsOFC phenotypes and 19 genetic variants in 13 genes/loci. These data suggest that IRF6, GRHL3, 8q24, VAX1, TGFA, FOXE1, ABCA4, NOG, GREM1, AXIN2, DVL2, WNT3A and WNT5A have high potential as biomarkers of nsOFC in populations of European descent. Although other meta-analyses that included European samples have been performed on a limited number of genetic variants, this study represents the first meta-analysis of all genetic markers that have been studied in connection with nsOFC in populations of European ancestry.

Associations of MGMT promoter hypermethylation with squamous intraepithelial lesion and cervical carcinoma: A meta-analysis

Background

In this research, an meta-analysis was performed for assessment of the associations between O⁶-methyguanine-DNA methyltransferase (MGMT) promoter hypermethylation possessing low-grade intraepithelial lesion (LSIL), high-grade intraepithelial lesion (HSIL), cervical cancer (CC), and clinicopathological characters of CC.

Methods

Literature selection were conducted through searching PubMed, Web of science, EMBASE, China National Knowledge Infrastructure and Wanfang databases (up to November 2018). An assessment of associations between MGMT methylation and LSIL, HSIL, CC risk and clinicopathological characteristics was performed through pooled odds ratios (ORs) with relevant 95% confidence intervals (CIs). Subgroup analyses, meta-regressions and Galbraith plots were conducted to conduct an exploration on the possible sources of heterogeneity. The genome-wide DNA methylation array studies were extracted from Gene Expression Omnibus (GEO) databases for validation of these outcomes.

Results

In this meta-analysis of 25 published articles, MGMT hypermethylation gradually elevated the rates among control group (12.16%), LSIL (20.92%), HSIL (36.33%) and CC (41.50%) specimens. MGMT promoter methylation was significant associated with the increased risk of LSIL by 1.74-fold (P<0.001), HSIL by 3.71-fold (P<0.001) and CC by 7.08-fold (P<0.001) compared with control. A significant association between MGMT promoter methylation with FIGO stage was also found (OR = 2.81, 95% CI: 1.79–4.41, p<0.001). The results of GEO datasets showed that 5 CpG sites in MGMT with a great diagnostic value for the screening of cervical cancer.

Conclusion

The meta-analysis indicated the association between MGMT promoter hypermethylation and squamous intraepithelial lesion and cervical cancer. MGMT methylation detection might have a potential value to be an epigenetic marker for the clinical diagnosis of cervical cancer.

Investigation of candidate genes of non-syndromic cleft lip with or without cleft palate, using both case-control and family-based association studies

OBJECTIVE

Non-syndromic cleft of the lip and/or palate (NSCL/P) is one of the most common polygenic diseases. In this study, both case-control and family-based association study were used to confirm whether the Single Nucleotide Polymorphisms (SNPs) were associated with NSCL/P.

METHODS

A total of 37 nuclear families and 189 controls were recruited, whose blood DNA was extracted and subjected to genotyping of SNPs of 27 candidate genes by polymerase chain reaction-improved multiple ligase detection reaction technology (PCR-iMLDR). Case-control statistical analysis was performed using the SPSS 19.0. Haplotype Relative Risk (HRR), transmission disequilibrium test (TDT), and Family-Based Association Test (FBAT) were used to test for over-transmission of the target alleles in case-parent trios. The gene-gene interactions on NSCL/P were analyzed by Unphased-3.1.4.

RESULTS

In case-control statistical analysis, only C14orf49 chr14_95932477 had statistically significant on genotype model (P = .03) and allele model (P = .03). Seven SNPs had statistically significant on TDT. None of 26 alleles has association with NSCL/P on FBAT. Some SNPs had haplotype-haplotype interactions and genotype-genotype interactions.

CONCLUSION

C14orf49 chr14_95932477 was significantly different between cases and controls on genotype model and allele model by case-control design. Seven SNPs were significantly different on HRR. Four SNPs were significantly different on TDT.

Prevalence of Congenital Anomalies in the Japan Environment and Children's Study

Background

The aims of the present report were to estimate the prevalence of congenital anomalies (CAs) among infants in Japan using data from the Japan Environment and Children’s Study (JECS) and to evaluate the validity of CA classification within JECS.

Methods

Data on CAs were collected at delivery and at age 1 month from the medical records of 101,825 infants at 15 regional centers. The analyses focused on 61 CAs, selected on the basis of reported associations with environmental exposure. Prevalence per 10,000 pregnancies (including miscarriages, stillbirths, and live births) was stratified according to four reporting patterns (at delivery, at age 1 month, at either, and at both). To evaluate the accuracy of observed CA prevalence, the medical records of 179 cases from a single JECS regional center underwent independent, retrospective re-evaluation.

Results

The prevalence of major CAs in four reporting patterns (at delivery, at age 1 month, at either, and at both) was 2.4, 2.6, 3.5, and 1.4 for myelomeningocele/spina bifida; 4.3, 4.2, 5.3, and 3.2 for cleft palate; 18.1, 17.4, 19.5, and 15.1 for cleft lip with or without cleft palate; 73.4, 100.3, 120.8, and 52.8 for congenital heart disease; and 10.5, 14.1, 15.0, and 9.6 for Down’s syndrome, respectively. In the subsample re-evaluation, CA diagnoses were confirmed for 92.7%, 93.3%, 90.5%, and 97.8% of cases in the four reporting patterns (at delivery, at age 1 month, at either, and at both), respectively.

Conclusions

The present report generated reliable data concerning the prevalence of major CAs in JECS.

Identification of DAPK1 Promoter Hypermethylation as a Biomarker for Intra-Epithelial Lesion and Cervical Cancer: A Meta-Analysis of Published Studies, TCGA, and GEO Datasets

Background: Promoter hypermethylation in death-associated protein kinase 1 (DAPK1) gene has been long linked to cervical neoplasia, but the established results remained controversial. Here, we performed a meta-analysis to assess the associations of DAPK1 promoter hypermethylation with low-grade intra-epithelial lesion (HSIL), high-grade intra-epithelial lesion (HSIL), cervical cancer (CC), and clinicopathological features of CC.

Methods: Published studies with qualitative methylation data were initially searched from PubMed, Web of Science, EMBASE, and China National Knowledge Infrastructure databases (up to March 2018). Then, quantitative methylation datasets, retrieved from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, were pooled to validate the results of published studies.

Results: In a meta-analysis of 37 published studies, DAPK1 promoter hypermethylation progressively increased the risk of LSIL by 2.41-fold (P = 0.012), HSIL by 7.62-fold (P < 0.001), and CC by 23.17-fold (P < 0.001). Summary receiver operating characteristic curves suggested a potential diagnostic value of DAPK1 promoter hypermethylation in CC, with a large area-under-the-curve of 0.83, a high specificity of 97%, and a moderate sensitivity of 59%. There were significant impacts of DAPK1 promoter hypermethylation on histological type (odds ratio (OR) = 3.53, P < 0.001) and FIGO stage of CC (OR = 2.15, P = 0.003). Then, a pooled analysis of nine TCGA and GEO datasets, covering 13 CPG sites within DAPK1 promoter, identified eight CC-associated sites, six sites with diagnostic values for CC (pooled specificities: 74–90%; pooled sensitivities: 70–81%), nine loci associated with the histological type of CC, and all 13 loci with down-regulated effects on DAPK1 mRNA expression.

Conclusion: The meta-analysis suggests that DAPK1 promoter hypermethylation is significantly associated with the disease severity of cervical neoplasia. DAPK1 methylation detection exhibits a promising ability to discriminate CC from cancer-free controls.

Association Between CRISPLD2 Polymorphisms and the Risk of Nonsyndromic Clefts of the Lip and/or Palate: A Meta-analysis

OBJECTIVE

Nonsyndromic clefts of the lip and/or palate (NSCL/P) are one of the most common polygenic diseases. Recently, many studies focused on the association between CRISPLD2 polymorphisms and NSCL/P risk. However, some studies have shown opposite results. In this study, meta-analysis was used to confirm whether CRISPLD2 polymorphism was associated with NSCL/P, and the possible mechanism between CRISPLD2 and NSCL/P was explored.

METHODS

Relevant studies were conducted on PubMed, Ovid, EBSCO, CINAHL, FMRS, Web of Science, CNKI, and Wanfang databases from their inception up to June 31, 2016. Review Manager 5.0.24 was used to analyze whether CRISPLD2 polymorphism was involved in NSCL/P by pooling odds ratios (ORs) and 95% confidence intervals (CIs). Potential publication bias was evaluated by visual inspection of the funnel plot.

RESULTS

CRISPLD2 rs4783099 was associated with cleft lip and/or palate (CL/P) statistically (OR = 3.18, P < .01). Compared to genotype TT, genotypes CC and CT were correlated significantly (OR = 2.04, P = .04) with CL/P. No evidence showed an association between genetic variation at the CRISPLD2 locus and cleft palate only (CP).

CONCLUSION

The polymorphism of CRISPLD2 rs4783099 is correlated with an increased risk of CL/P.

Association Study of Transforming Growth Factor Alpha TaqI Polymorphism and the Risk of Cleft Lip and/or Palate in an Iranian Population

BACKGROUND

The aim of this study is to evaluate the association of TGFA TaqI polymorphism with nonsyndromic cleft lip and/or palate (NSCLP) in an Iranian population.

METHODS

In this case-control study, 113 children with NSCLP and 209 controls were included. Genotyping of the TaqI polymorphism was performed by polymerase chain reaction and restriction fragment length polymorphism methods. A p-value of <0.05 was considered statistically significant.

RESULTS

For the TGFA TaqI polymorphism, the distributions of genotypes in the NSCLP (p = 0.810) and control group (p = 0.422) were in Hardy-Weinberg equilibrium. There was no statistically significant difference in the genotype distribution (p = 0.059) and allele frequency (p = 0.065) of the TGFA TaqI polymorphism in the NSCLP and control groups.

CONCLUSION

TGFA TaqI polymorphism was not associated with the risk of NSCLP in Iranian children. Birth Defects Research 109:1386-1389, 2017.© 2017 Wiley Periodicals, Inc.

BMP4 rs17563 polymorphism and nonsyndromic cleft lip with or without cleft palate: A meta-analysis

BACKGROUND

Previous studies have investigated the relationship between human bone morphogenetic protein 4 gene (BMP4) rs17563 polymorphism and nonsyndromic cleft lip with or without cleft palate (NSCL/P). However, the results remained inconsistent. Therefore, we conducted a meta-analysis to assess the effect of BMP4 rs17563 polymorphism on NSCL/P.

METHODS

Electronic searches in 5 databases were conducted to select all eligible studies up to March 2017. Odds ratios (ORs) with the corresponding 95% confidence intervals (CIs) were calculated to estimate the association. Sensitivity analysis was performed to evaluate the results stability by excluding each study in turn. Publication bias was assessed by Begg funnel plots and Egger test.

RESULTS

A total of 11 case-control studies were included in the meta-analysis. The pooled frequency of the minor allele C for BMP4 rs17563 was lower in Asians (pooled frequency = 0.33, 95% CI: 0.29-0.37) than in Brazilian population (pooled frequency = 0.47, 95% CI: 0.40-0.54). The overall results showed no significant association of BMP4 rs17563 polymorphism with NSCL/P risk. However, the results turned out to be different when stratified by ethnicity. BMP4 rs17563 polymorphism was associated with a higher risk of NSCL/P among Asian ethnicity (C vs T: OR = 1.33, 95% CI: 1.02-1.73; CC vs TT: OR = 2.10, 95% CI: 1.28-3.43; CC vs TT + TC: OR = 2.16, 95% CI: 1.34-3.47) and among Caucasian population (TC vs TT: OR = 3.36, 95% CI: 2.03-5.54; TC + CC vs TT: OR = 3.71, 95% CI: 2.43-5.69). Among Brazilian population, BMP4 rs17563 polymorphism exerted a significantly protective effect on NSCL/P (C vs T: OR = 0.70, 95% CI: 0.58-0.84; CC vs TT: OR = 0.54, 95% CI: 0.33-0.88; TC vs TT: OR = 0.55, 95% CI: 0.44-0.69; TC + CC vs TT: OR = 0.56, 95% CI: 0.45-0.69).

CONCLUSION

The results suggest that the C allele of BMP4 rs17563 may be a risk factor for NSCL/P among Asians and Caucasians, and may be a protective factor for NSCL/P in Brazilian population. Future large-sample studies with appropriate designs among specific populations are warranted to evaluate the association.

Certain Polymorphisms in SP110 Gene Confer Susceptibility to Tuberculosis: A Comprehensive Review and Updated Meta-Analysis

PURPOSE

Numerous studies have assessed the association of SP110 gene variants with tuberculosis (TB), but the results were inconsistent. Through a comprehensive review and meta-analysis, our study aimed to clarify the nature of genetic risks contributed by 11 polymorphisms for the development of TB.

MATERIALS AND METHODS

Through searching PubMed, web of science, China National Knowledge Infrastructure (CNKI) databases, a total of 11 articles including 13 independent studies were selected. The pooled odd ratios (ORs) along with their corresponding 95% confidence interval (CI) were estimated for allelic comparisons, additive model (homozygote comparisons; heterozygote comparisons), dominant model and recessive model. We also assessed the heterogeneity across the studies and publication bias.

RESULTS

The results of combined analysis revealed a significantly increased risk of TB for single nucleotide polymorphism (SNP) rs9061 in all five comparisons (allelic comparisons: OR=1.28, 95% CI=1.14-1.44, p<0.0001; homozygote comparisons: OR=2.84, 95% CI=1.84-4.38, p<0.00001; heterozygote comparisons: OR=1.23, 95% CI=1.05-1.43, p=0.009; dominant model: OR=1.32, 95% CI=1.14-1.53, p=0.0003; recessive model: OR=2.26, 95% CI=1.18-4.34, p=0.01). In subgroup analysis, the risk of TB associated with SNP rs9061 appeared to be increased. Moreover, increased risk of TB was also found in Asian subgroup of SNP rs11556887, while decreased risk of TB appeared in large sample size subgroup of SNP rs1135791. No significant association was observed between other SNPs and the risk of TB.

CONCLUSION

Our meta-analysis suggested that the variant of SNP rs9061 might be a risk factor for TB.

TGFα expression in myeloid malignancies

Background

Transforming growth factor α (TGFα) is a peptide growth factor known to be expressed in normal haemopoiesis. It is also expressed in a range of epithelial neoplasms but has not been assessed in haemopoietic malignancies. We have performed an immunohistochemical evaluation of TGFα in acute and chronic myeloid malignancies.

Methods

TGFα expression was semiquantitatively assessed in 69 normal bone marrow trephines and 157 cases of myeloid malignancy using an immunohistochemical approach.

Results

Blast cells of myeloid origin in acute myeloid leukaemia (AML), myelodysplasia and accelerated and blast phases of chronic myeloid leukaemia (CML) were TGFα positive. In acute promyelocytic leukaemia the neoplastic cells had significantly weaker TGFα expression than seen in other forms of AML. The blast cells in CML-accelerated and blast phases were positive with similar expression to AML.

Conclusions

TGFα is expressed in neoplastic myeloblasts and could, therefore, be used as blast cell biomarker in diagnostic haematopathology. In addition, TGFα immunohistochemistry may be of use in identifying a therapeutic target.

Association between Estrogen Receptor-α Gene XbaI and PvuII Polymorphisms and Periodontitis Susceptibility: A Meta-Analysis

Background. Certain studies have previously explored the association between the estrogen receptor-α (ER-α) gene polymorphisms and periodontitis susceptibility, although the current results are controversial. The present study, using meta-analysis, aimed to investigate the nature of the genetic susceptibility of the ER-α for developing periodontitis. Methods. A comprehensive literature search of PubMed, Embase, CNKI, and Wanfang databases was conducted up to January 8, 2015. Statistical manipulation was performed using Stata version 13.0 software. Odds ratios (ORs) and corresponding 95% confident intervals (CIs) were calculated to estimate the association in five genetic models. Results. A total of 17 eligible case-control studies from seven identified publications consisting of nine studies for the XbaI polymorphism and eight studies for the PvuII polymorphism were included in the meta-analysis. We found elevated risk of periodontitis in XbaI XX genotype carriers. Moreover, subgroup analyses demonstrated increased risk for chronic periodontitis of XbaI XX genotype carriers, specifically in the Chinese Han female population. No significant association was observed between PvuII polymorphism and periodontitis. Conclusion. Current evidence indicated that the homozygote (XX) genotype of ER-α gene XbaI polymorphism, but not PvuII mutation, may increase the risk of chronic periodontitis, specifically in the Chinese Han female population.

Systematic Review by Multivariate Meta-analyses on the Possible Role of Tumor Necrosis Factor-α Gene Polymorphisms in Association with Ischemic Stroke

A number of studies have investigated the association between tumor necrosis factor (TNF)-α gene polymorphisms and ischemic stroke susceptibility. However, results of different individual studies are often inconsistent. To provide a more robust evaluation of the association between polymorphisms of the TNF-α gene and ischemic stroke risk, we performed a systematic review with multivariate meta-analyses. PubMed, Embase, CNKI, and WanFang databases were searched up to December 20, 2014. Two reviewers independently extracted information and assessed quality of included studies after all the eligible studies were identified. Afterward, multivariate meta-analyses were performed using Stata 13. The estimation of polymorphisms and disease risk was presented by odds ratios (ORs) and corresponding 95 % confidence intervals (CIs). Forty-nine eligible case-control studies from 25 articles that explored the association between 10 TNF-α polymorphisms and ischemic stroke were indentified from aforementioned databases. The results of multivariate meta-analysis showed a significant association between -238G/A polymorphism (4760 patients and 4389 controls) and ischemic stroke risk in heterozygotes compared with wild genotype (AG vs. GG: OR 1.44, 95 % CI 1.11-1.87; AA vs. GG: OR 1.98, 95 % CI 0.73-5.40). No significant association of -308G/A, -857C/T, and -1031T/C polymorphisms was observed. The results of stratification analyses of -238G/A polymorphism showed that the AG genotype only increased the risk of ischemic stroke in Asians compared to GG genotype. No additional significant association was observed in this study. In conclusion, the present systematic review and meta-analysis support a prominent role of the TNF-α -238G/A polymorphism in the risk of ischemic stroke in Asian adults only, but do not support the role of -308G/A, -857C/T, -1031T/C, -244G/A, -367G/A, -646G/A, -806C/T, -863C/A, and +448G/A in the risk of ischemic stroke. The current evidence warrants further studies with high quality and large sample size to confirm.

Developments in our understanding of the genetic basis of birth defects

Birth defects are a major cause of morbidity and mortality worldwide. There has been much progress in understanding the genetic basis of familial and syndromic forms of birth defects. However, the etiology of nonsydromic birth defects is not well-understood. Although there is still much work to be done, we have many of the tools needed to accomplish the task. Advances in next-generation sequencing have introduced a sea of possibilities, from disease-gene discovery to clinical screening and diagnosis. These advances have been fruitful in identifying a host of candidate disease genes, spanning the spectrum of birth defects. With the advent of CRISPR-Cas9 gene editing, researchers now have a precise tool for characterizing this genetic variation in model systems. Work in model organisms has also illustrated the importance of epigenetics in human development and birth defects etiology. Here we review past and current knowledge in birth defects genetics. We describe genotyping and sequencing methods for the detection and analysis of rare and common variants. We remark on the utility of model organisms and explore epigenetics in the context of structural malformation. We conclude by highlighting approaches that may provide insight into the complex genetics of birth defects.

Association between CEBPE Variant and Childhood Acute Leukemia Risk: Evidence from a Meta-Analysis of 22 Studies

The CCAAT/enhancer binding proteins (CEBPs) have been involved in the etiology of acute leukemia (AL) and investigated in numerous genetic association studies, however, the results were inconclusive. The current meta-analysis was conducted to clarify the effect of CEBPE rs2239633 variant on childhood AL risk. Electronic literature search was performed on August 15, 2014, from databases of Medline, PubMed, Embase, and Web of Science. A total of 22 case-control studies were eligible for the pooled analysis. The results demonstrated that rs2239633 A allele was significantly associated with a decreased risk of childhood AL (A vs G: OR=0.87, 95%CI = 0.80, 0.94, p<0.001), especially in B-cell ALL subgroup (A vs G: OR = 0.79, 95%CI = 0.74, 0.83, p<0.001), but not among T-cell ALL or AML subgroups. In the stratified analysis by ethnicity, the association was observed in Europeans (A vs G: OR = 0.80, 95%CI = 0.76, 0.84, p<0.001) but not in Asian and mixed populations. Moreover, the results of sensitivity and cumulative meta-analysis indicated the robustness of our results. Also, Begg’s and Egger’s tests did not indicate any evidence of obvious asymmetry. In summary, our study provided evidence that CEBPE rs2239633 variant is associated with decreased risk of childhood B-cell ALL in Europeans.

Association between BMP4 rs17563 polymorphism and NSCL/P risk: a meta-analysis

Objective. To investigate the association between bone morphogenetic protein 4 (BMP4) rs17563 polymorphism and nonsyndromic cleft lip with or without palate (NSCL/P) risk. Methods. Four online databases were researched and the related publications were collected. Odds ratio (OR) with 95% confidence interval (CI) was applied to assess the relationship; publication bias, metaregression, and sensitivity analysis were conducted to guarantee the strength of results. Results. Six published case-control studies were collected. Overall, no significant association between BMP4 rs17563 polymorphism and NSCL/P risk was found. It was notable that significant susceptibility on different ethnicity was observed in the stratified analysis. For Chinese population, the BMP4 rs17563 polymorphism was a significantly increased risk for NSCL/P (C versus T: OR = 1.52, 95% CI = 1.28–1.82, P < 0.01, I² = 0%; CC versus TT: OR = 2.58, 95% CI = 1.74–3.82, P < 0.01, I² = 0%; TC + CC versus TT: OR = 1.45, 95% CI = 1.14–1.84, P < 0.01, I² = 0%; CC versus TT + TC: OR=2.46, 95% CI = 1.46–4.14, P < 0.01, I² = 47.0%). On the contrary, significantly protective effects were found in Brazilian population (C versus T: OR = 0.69, 95% CI = 0.50–0.96, P = 0.03, I² = 68.5%; TC versus TT: OR = 0.52, 95% CI = 0.40–0.68, P < 0.01, I² = 0%; TC + CC versus TT: OR = 0.52, 95% CI = 0.35–0.78, P < 0.010, I² = 54.4%). Conclusion. This meta-analysis indicated that BMP4 rs17563 polymorphism could play a different role during the development of NSCL/P based on ethnicity diversity.

MTHFD1 polymorphism as maternal risk for neural tube defects: a meta-analysis

Recently, the association between methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) G1958A polymorphism and neural tube defects (NTD) susceptibility has been widely investigated; however, the results remained inconclusive. Hence, we conducted a meta-analysis to evaluate the effect of MTHFD1 G1958A polymorphism on NTD. The relative literatures were identified by search of the electronic databases PubMed, MEDLINE, and EMBASE. The extracted data were statistically analyzed, and pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated to estimate the association strength using Stata version 11.0 software. Finally, ten studies met our inclusion criteria, including 2,132/4,082 in NTD infants and controls; 1,402/3,136 in mothers with NTD offspring and controls; and 993/2,879 in fathers with NTD offspring and controls. This meta-analysis showed that, compared with the mothers with GG genotype, the women with AA genotype had an increased risk of NTD in their offspring, with OR values and 95 % CI at 1.39 (1.16-1.68), p < 0.001. Interestingly, fathers with AG genotype had a significant decreased risk of NTD offspring (OR = 0.79, 95 % CI = 0.66-0.94, p = 0.009). However, there was no significant association between the MTHFD1 G1958A polymorphism in NTD patients and the risk of NTD. In conclusion, the present meta-analysis provided evidence of the association between maternal MTHFD1 G1958A polymorphism and NTD susceptibility.

Accelerated wound closure in vitro by fibroblasts from a subgroup of cleft lip/palate patients: role of transforming growth factor-α

In a fraction of patients surgically treated for cleft lip/palate, excessive scarring disturbs maxillary growth and dento-alveolar development. Since certain genes are involved in craniofacial morphogenesis as well as tissue repair, a primary defect causing cleft lip/palate could lead to altered wound healing. We performed in vitro wound healing assays with primary lip fibroblasts from 16 cleft lip/palate patients. Nine foreskin fibroblast strains were included for comparison. Cells were grown to confluency and scratch wounds were applied; wound closure was monitored morphometrically over time. Wound closure rate showed highly significant differences between fibroblast strains. Statistically, fibroblast strains from the 25 individuals could be divided into three migratory groups, namely “fast”, “intermediate”, and “slow”. Most cleft lip/palate fibroblasts were distributed between the “fast” (5 strains) and the “intermediate” group (10 strains). These phenotypes were stable over different cell passages from the same individual. Expression of genes involved in cleft lip/palate and wound repair was determined by quantitative PCR. Transforming growth factor-α mRNA was significantly up-regulated in the “fast” group. 5 ng/ml transforming growth factor-α added to the culture medium increased the wound closure rate of cleft lip/palate strains from the “intermediate” migratory group to the level of the “fast”, but had no effect on the latter group. Conversely, antibody to transforming growth factor-α or a specific inhibitor of its receptor most effectively reduced the wound closure rate of “fast” cleft lip/palate strains. Thus, fibroblasts from a distinct subgroup of cleft lip/palate patients exhibit an increased migration rate into wounds in vitro, which is linked to higher transforming growth factor-α expression and attenuated by interfering with its signaling.

SUMO1 genetic polymorphisms may contribute to the risk of nonsyndromic cleft lip with or without palate: a meta-analysis

OBJECTIVE

We conducted the present meta-analysis to investigate whether single-nucleotide polymorphisms (SNPs) in the SUMO1 gene contribute to the risk of nonsyndromic cleft lip with or without palate (NSCL/P).

METHOD

The Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013), and the Chinese Biomedical Database (CBM) (1982-2013) were searched without language restrictions. Meta-analysis was performed with the use of the STATA statistical software.

RESULTS

Six studies with a total of 1381 NSCL/P patients and 2054 control subjects were included. Twenty-seven functional polymorphisms in the SUMO1 gene were assessed. Our results indicated that SUMO1 genetic polymorphisms were correlated with an increased risk of NSCL/P. Subgroup analysis by the SNP type indicated that 4 functional polymorphisms (rs12470401 T>C, rs16838917 A>G, rs12470529 A>G, and rs7572505 A>G) in the SUMO1 gene might be strongly correlated with NSCL/P risk. Furthermore, ethnicity-stratified analysis demonstrated that SUMO1 genetic polymorphisms were closely related to an increased risk of NSCL/P among both Asians and Caucasians.

CONCLUSION

Our findings provide empirical evidence that SUMO1 genetic polymorphisms might be strongly involved in the etiology of NSCL/P, especially for rs12470401 T>C, rs16838917 A>G, rs12470529 A>G, and rs7572505 A>G polymorphisms.