Zhen-Jian Zhuo

Functional Polymorphisms at ERCC1/XPF Genes Confer Neuroblastoma Risk in Chinese Children

Variations in nucleotide excision repair pathway genes may predispose to initiation of cancers. However, polymorphisms of ERCC1/XPF genes and neuroblastoma risk have not been investigated before. To evaluate the relevance of polymorphisms of ERCC1/XPF genes in influencing neuroblastoma susceptibility, we genotyped four polymorphisms in ERCC1/XPF genes using a Chinese population of 393 cases and 812 controls. The results showed that ERCC1 rs2298881 and rs11615 predisposed to enhanced neuroblastoma risk [CA vs. AA: adjusted odds ratio (OR) = 1.94, 95% confidence interval (CI) = 1.30–2.89, P = 0.0012; CC vs. AA: adjusted OR = 2.18, 95% CI = 1.45–3.26, P = 0.0002 for rs2298881, and AG vs. GG: adjusted OR = 1.31, 95% CI = 1.02–1.69, P = 0.038 for rs11615]. Moreover, XPF rs2276466 was also associated with increased neuroblastoma risk (GG vs. CC: adjusted OR = 1.66, 95% CI = 1.02–2.71, P = 0.043). In the combined analysis of ERCC1, we found that carriers with 2–3 risk genotypes were more likely to get risk of neuroblastoma, when compared to those with 0–1 risk genotype (adjusted OR = 1.75; 95% CI = 1.25–2.45, P = 0.0012). Our study indicates that common genetic variations in ERCC1/XPF genes predispose to neuroblastoma risk, which needs to be further validated by ongoing efforts.

NFKB1 -94insertion/deletion ATTG polymorphism and cancer risk: Evidence from 50 case-control studies

Nuclear factor-kappa B1 (NF-κB1) is a pleiotropic transcription factor and key contributor to tumorigenesis in many types of cancer. Numerous studies have addressed the association of a functional insertion (I)/deletion (D) polymorphism (-94ins/delATTG, rs28362491) in the promoter region of NFKB1 gene with the risk of various types of cancer; however, their conclusions have been inconsistent. We therefore conducted a meta-analysis to reevaluate this association. PubMed, EMBASE, China National Knowledge infrastructure (CNKI), and WANFANG databases were searched through July 2016 to retrieve relevant studies. After careful assessment, 50 case-control studies, comprising 18,299 cases and 23,484 controls were selected. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were used to determine the strength of the association. The NFKB1 -94ins/delATTG polymorphism was associated with a decreased risk of overall cancer in the homozygote model (DD vs. II): OR = 0.75, 95% CI = 0.64-0.87); heterozygote model (ID vs. II): OR = 0.91, 95% CI = 0.83-0.99; recessive model (DD vs. ID/II): OR = 0.81, 95% CI = 0.71-0.91; dominant model (ID/DD vs. II): OR = 0.86, 95% CI = 0.78-0.95; and allele contrast model (D vs. I): OR = 0.88, 95% CI = 0.81-0.95). Subgroup and stratified analyses revealed decreased risks for lung cancer, nasopharyngeal carcinoma, prostate cancer, ovarian cancer, and oral squamous cell carcinoma, and this association held true also for Asians (especially Chinese subjects) in hospital-based studies, and in studies with quality scores less than nine. Well-designed, large-scale case-control studies are needed to confirm these results.

Association between TP53 gene Arg72Pro polymorphism and Wilms’ tumor risk in a Chinese population

Wilms’ tumor is one of the most prevalent pediatric malignancies, ranking fourth in childhood cancer worldwide. TP53 is a critical tumor suppressor gene, which encodes a 53 kDa protein, p53. The p53 functions to protect against cancer by regulating cell cycle and apoptosis and maintaining DNA integrity. TP53 gene is highly polymorphic. Several TP53 gene polymorphisms have been considered to be associated with cancer risk. Of them, a nonsynonymous polymorphism, Arg72Pro (rs1042522 C>G), has been most extensively studied for the association with cancer risk; however, few studies have investigated its effect on Wilms’ tumor. Because of the central role of p53 in cell cycle control, the TP53 gene Arg72Pro polymorphism is also a good potential candidate predisposition locus for this pediatric cancer. We genotyped this polymorphism in 145 patients and 531 cancer-free controls recruited from Chinese children by Taqman methodology. Overall, our result suggested a lack of association between the TP53 gene Arg72Pro polymorphism and Wilms’ tumor. In the stratified analysis, we found that carriers of CG/GG genotypes had a significantly increased Wilms’ tumor risk in children not older than 18 months (adjusted odds ratio =2.04, 95% confidence interval =1.003–4.13, P=0.049) compared with CC genotype carriers. Our study indicated that the TP53 gene Arg72Pro polymorphism may have a weak, age-related effect on Wilms’ tumor risk in Chinese children. These findings need further validations in other populations with larger sample size.

CASC15 gene polymorphisms reduce neuroblastoma risk in Chinese children

In this case-control study, we analyzed the association between three single nucleotide polymorphisms (SNPs) in the CASC15 gene (rs6939340 A>G, rs4712653 T>C, and rs9295536 C>A) and neuroblastoma susceptibility in the Guangdong and Henan populations of China. We genotyped and analyzed 118 cases and 281 control subjects from Henan province and combined them with previously published data from the Guangdong population. In the Henan population, only the rs6939340 G>A variant homozygote AA was associated with decreased neuroblastoma risk [AA vs. GG: adjusted odds ratio (OR) = 0.47, 95% confidence interval (CI) = 0.23-0.98; P=0.045]. All three polymorphisms, individually and in combination, were associated with decreased neuroblastoma susceptibility in the Guangdong population. Moreover, subjects carrying 1-3 of these protective genotypes had lower neuroblastoma susceptibility than non-carriers (adjusted OR=0.65, 95% CI=0.51-0.84, P=0.0007). These results show that all three genetic variants of CASC15 identified in a genome-wide association study (GWAS) decrease neuroblastoma risk in two distinct Chinese populations.

Associations between LMO1 gene polymorphisms and Wilms’ tumor susceptibility

Wilms tumor is the most common childhood renal malignancy. A genome-wide association study identified LIM domain only 1 (LMO1) as having oncogenic potential. We examined the associations between LMO1 gene polymorphisms and susceptibility to Wilms tumor. In this hospital-based, case-control study, we recruited 145 children with Wilms tumor and 531 cancer-free children. Four polymorphisms (rs110419 A>G, rs4758051 G>A, rs10840002 A>G and rs204938 A>G) were genotyped using Taqman methodology. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure the associations between selected polymorphisms and Wilms tumor susceptibility. Only rs110419 AG was found to be protective against Wilms tumor (adjusted OR = 0.62, 95% CI = 0.41-0.94, P = 0.024) when compared to rs110419 AA. Wilms tumor risk was markedly greater in children with 1-4 risk genotypes (nucleotide alterations) than in those with no risk genotypes (adjusted OR = 1.84, 95% CI = 1.25-2.69, P = 0.002). In a stratified analysis, the protective effect of rs110419 AG/GG was predominant in males. The association of 1-4 risk genotypes with Wilms tumor risk was limited to subgroups of children who were >18 months old, female, and in clinical stages III+IV. Thus, LMO1 gene polymorphisms may contribute to Wilms tumor risk, but this conclusion should be validated in other populations and larger studies.Wilms’ tumor is the most common childhood renal malignancy. A genome-wide association study identified LIM domain only 1 (LMO1) as having oncogenic potential. We examined the associations between LMO1 gene polymorphisms and susceptibility to Wilms’ tumor. In this hospital-based, case-control study, we recruited 145 children with Wilms’ tumor and 531 cancer-free children. Four polymorphisms (rs110419 A>G, rs4758051 G>A, rs10840002 A>G and rs204938 A>G) were genotyped using Taqman methodology. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure the associations between selected polymorphisms and Wilms’ tumor susceptibility. Only rs110419 AG was found to be protective against Wilms’ tumor (adjusted OR = 0.62, 95% CI = 0.41–0.94, P = 0.024) when compared to rs110419 AA. Wilms’ tumor risk was markedly greater in children with 1–4 risk genotypes (nucleotide alterations) than in those with no risk genotypes (adjusted OR = 1.84, 95% CI = 1.25–2.69, P = 0.002). In a stratified analysis, the protective effect of rs110419 AG/GG was predominant in males. The association of 1–4 risk genotypes with Wilms’ tumor risk was limited to subgroups of children who were >18 months old, female, and in clinical stages III+IV. Thus, LMO1 gene polymorphisms may contribute to Wilms’ tumor risk, but this conclusion should be validated in other populations and larger studies.

Polymorphisms in the XPC gene and gastric cancer susceptibility in a Southern Chinese population

Previous studies have reported that XPC gene polymorphisms may modify the individual susceptibility to gastric cancer. In this case–control study with a total of 1,142 cases and 1,173 controls, four potentially functional polymorphisms were genotyped in the XPC gene (rs2228001 A>C, rs2228000 C>T, rs2607775 C>G, and rs1870134 G>C) by Taqman assays and their associations were analyzed with the risk of gastric cancer in a Southern Chinese population. No significant association between any of XPC polymorphisms and gastric cancer risk was detected except for a borderline association with the rs2228000 CT/TT genotype (crude odds ratio =0.86, 95% confidence interval =0.73–1.02, P=0.088) when compared to the rs2228000 CC genotype. Further stratified analysis revealed that the protective effect of rs2228000 CT/TT on the risk of gastric cancer was only significant among subjects older than 58 years. In summary, results indicated that genetic variations in XPC gene may play a weak effect on gastric cancer susceptibility in Southern Chinese population, which warrants further confirmation in larger prospective studies with different ethnic populations.

XPA gene polymorphisms and risk of neuroblastoma in Chinese children: a two-center case-control study

Neuroblastoma is a malignant tumor arising from the developing sympathetic nervous system, which mainly affects children. Variations in XPA gene have been shown to confer cancer susceptibility. However, no investigation has been reported regarding the association between XPA polymorphisms and neuroblastoma risk. This study was conducted to measure the association of XPA polymorphisms with neuroblastoma susceptibility in Chinese children. In this hospital-based case-control study with 393 cases and 812 controls, we genotyped two polymorphisms (rs1800975 T>C, and rs3176752 G>T) in XPA gene to access their contributions to neuroblastoma risk by TaqMan methods. The strength of the association with neuroblastoma risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs). No single polymorphism was found to predispose to neuroblastoma susceptibility. When risk genotypes were combined, we found that carriers of 1-2 risk genotypes had significantly increased neuroblastoma risk (adjusted OR=1.28; 95% CI=1.001-1.64, P=0.049), when compared to non-carriers. Stratification analysis by age, gender, sites of origin and clinical stages failed to show any significant association. Our study provides cues that XPA gene polymorphisms may exert a weak effect in neuroblastoma risk. This finding needs further validations by larger sample size studies.

RAN/RANBP2 polymorphisms and neuroblastoma risk in Chinese children: a three-center case-control study

The genetic etiology of sporadic neuroblastoma remains largely obscure. RAN and RANBP2 genes encode Ras-related nuclear protein and Ran-binding protein 2, respectively. These two proteins form Ran-RanBP2 complex that regulate various cellular activities including nuclear transport. Aberrant functions of the two proteins are implicated in carcinogenesis. Given the unknown role of RAN/RANBP2 single nucleotide polymorphisms (SNPs) in neuroblastoma risk, we performed a multi-center case-control study in Chinese children to assess the association of the RAN/RANBP2 SNPs with neuroblastoma risk. We analyzed three potentially functional SNPs in RAN gene (rs56109543 C>T, rs7132224 A>G, rs14035 C>T) and one in RANBP2 (rs2462788 C>T) in 429 cases and 884 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to access the association between these four polymorphisms and neuroblastoma risk. No single variant was found to statistically significantly associate with neuroblastoma risk. However, individuals with 3 protective genotypes were less likely to develop neuroblastoma, in comparison to non-carriers (adjusted OR=0.33; 95% CI=0.12-0.96; P=0.042), as well as those with 0-2 protective genotypes (adjusted OR=0.33; 95% CI=0.11-0.94; P=0.038). Stratified analysis revealed no significant association for any of the four polymorphisms. Further studies are warranted to validate the weak impact of RAN/RANBP2 SNPs on neuroblastoma risk.

Association between NEFL Gene Polymorphisms and Neuroblastoma Risk in Chinese Children: A Two-Center Case-Control Study

Neuroblastoma is a lethal tumor that mainly occurs in children. To date, the genetic etiology of sporadic neuroblastoma remains obscure. A previous study identified three neuroblastoma susceptibility loci (rs11994014 G>A, rs2979704 T>C, rs1059111 A>T) in neurofilament light (NEFL) gene. Here, we attempted to evaluate the contributions of these three single nucleotide polymorphisms to neuroblastoma susceptibility in Chinese children. We genotyped these three polymorphisms using subjects from Guangdong province (256 cases and 531 controls) and Henan province (118 cases and 281 controls). Logistic regression models were performed to generate odds ratios and 95% confidence intervals to access the association of these three polymorphisms with neuroblastoma risk. Overall, we failed to provide any evidence supporting the association between these three polymorphisms and neuroblastoma susceptibility, either in single center population or in the combined population. Moreover, such null association was also observed when the samples were stratified by age, gender, tumor sites, and clinical stages. In the future, larger samples from different ethnicities are needed to clarify the role of NEFL gene polymorphisms in neuroblastoma risk.

Associations between lncRNA MEG3 polymorphisms and neuroblastoma risk in Chinese children

Neuroblastoma is the third most common childhood cancer after leukemias and cancer of the central nervous system. Long noncoding RNA MEG3 polymorphisms have been shown to confer cancer susceptibility; however, their roles in the genetic predisposition to neuroblastoma remain unclarified. To answer this question, we genotyped two MEG3 polymorphisms, rs7158663 G>A and rs4081134 G>A, in 392 neuroblastoma children and 783 controls by TaqMan method. The results showed that neither single locus nor the combination analysis supported an association between MEG3 polymorphism and neuroblastoma risk. Interestingly, we found that subjects carrying rs4081134 AG/AA genotypes significantly tended to develop neuroblastoma among subgroups with age >18 month (adjusted OR=1.36, 95% CI=1.01-1.84) and clinical stage III+IV disease (adjusted OR=1.47, 95% CI=1.08-1.99), when compared with reference group. In the combined analysis of MEG3 polymorphisms, we found that carriers of 2 risk genotypes were more likely to have higher risk of developing neuroblastoma than those with 0-1 risk genotype among children more than 18 months of age (adjusted OR=1.36, 95% CI=1.01-1.84, P=0.042), and with clinical stages III+IV disease (adjusted OR=1.47, 95% CI=1.08-2.00, P=0.014). Our data suggest MEG3 as a weak-effect neuroblastoma susceptibility gene. Well-designed studies with large sample studies are needed to further validate this finding.