Fuman Qiu

A functional copy number variation in the WWOX gene is associated with lung cancer risk in Chinese

WW domain-containing oxidoreductase (WWOX) is a tumor suppressor that has been reported to lose function due to genetic alterations in several cancers. WWOX maps to the common chromosomal fragile site FRA16D and several copy number variations (CNVs) were found within this gene. In this study, we investigated the association between the CNVs of WWOX and lung cancer risk in four independent case-control studies, which are on 2942 lung cancer cases and 3074 cancer-free controls of southern, eastern and northern Chinese. A common CNV-67048 was genotyped by the Taqman real-time PCR, and its biological effect was accessed with protein expression and sequencing assays. We found that in comparison with the common 2-copy genotype, the carriers of loss variant genotypes (1-copy or 0-copy) had a significantly increased risk of lung cancer (adjusted OR = 1.39, 95% CI = 1.24-1.55, P = 9.01×10(-9)) in a dose-response manner (Ptrend = 1.12 × 10(-10)), and the WWOX protein expressions in lung cancer tissues were significantly lower (P = 0.036), accompanying a higher rate of exons absence (P = 0.021) in subjects with loss genotypes of CNV-67048. Our data suggest that the loss genotypes of CNV-67048 in WWOX predispose their carriers to lung cancer; this might be related with altered WWOX gene expression and exons absence in them.

Functional Polymorphisms of CHRNA3 Predict Risks of Chronic Obstructive Pulmonary Disease and Lung Cancer in Chinese

Recently, several genome-wide association studies (GWAS) have identified many susceptible single nucleotide polymorphisms (SNPs) for chronic obstructive pulmonary disease (COPD) and lung cancer which are two closely related diseases. Among those SNPs, some of them are shared by both the diseases, reflecting there is possible genetic similarity between the diseases. Here we tested the hypothesis that whether those shared SNPs are common predictor for risks or prognosis of COPD and lung cancer. Two SNPs (rs6495309 and rs1051730) located in nicotinic acetylcholine receptor alpha 3 (CHRNA3) gene were genotyped in 1511 patients with COPD, 1559 lung cancer cases and 1677 controls in southern and eastern Chinese populations. We found that the rs6495309CC and rs6495309CT/CC variant genotypes were associated with increased risks of COPD (OR = 1.32, 95% C.I. = 1.14–1.54) and lung cancer (OR = 1.57; 95% CI = 1.31–1.87), respectively. The rs6495309CC genotype contributed to more rapid decline of annual Forced expiratory volume in one second (FEV1) in both COPD cases and controls (P<0.05), and it was associated with advanced stages of COPD (P = 0.033); the rs6495309CT/CC genotypes conferred a poor survival for lung cancer (HR = 1.41, 95%CI = 1.13–1.75). The luciferase assays further showed that nicotine and other tobacco chemicals had diverse effects on the luciferase activity of the rs6495309C or T alleles. However, none of these effects were found for another SNP, rs1051730G>A. The data show a statistical association and suggest biological plausibility that the rs6495309T>C polymorphism contributed to increased risks and poor prognosis of both COPD and lung cancer.

Effects of a Functional Variant c.353T>C in Snai1 on Risk of Two Contextual Diseases. Chronic Obstructive Pulmonary Disease and Lung Cancer

RATIONALE Epithelial-mesenchymal transition (EMT) plays a key role in the development of chronic obstructive pulmonary disease (COPD) and lung cancer. OBJECTIVES There are five major EMT regulatory genes (Snai1, Slug, Zeb1, Zeb2, and Twist1) involved in EMT. We hypothesized that germline variants in these genes may influence the development of both diseases. METHODS Seven genetic variants were genotyped in two two-stage case-control studies with 2,072 lung cancer cases and 2,077 control subjects, and 1,791 patients with COPD and 1,940 control subjects to show their associations with development of both diseases. MEASUREMENTS AND MAIN RESULTS An exon variant c.353T>C(p.Val118Ala) of Snai1 harbored decreased risks of lung cancer (CT/CC vs. TT: odds ratio [OR], 0.76; 95% confidence interval [CI], 0.65-0.90) and COPD (CC vs. CT vs. TT: OR, 0.75; 95% CI, 0.63-0.89), and c.353T>C affected lung cancer risk indirectly through COPD (COPD accounted for 6.78% of effect that the variant had on lung cancer). Moreover, c.353T>C was correlated with lung cancer stages in smoking patients (P = 0.013), and those with the c.353C genotypes were less likely to have metastasis at diagnosis than those with the c.353TT genotype (OR, 0.60; 95% CI, 0.41-0.88). The c.353C allele encoding p.118Ala attenuated Snai1s ability to up-regulate mesenchymal biomarkers (i.e., fibronectin and vimentin) expression, and to promote EMT-like changes, including morphologic changes, cell migration, and invasion. However, these effects were not observed for the other variants. CONCLUSIONS The functional germline variant c.353T>C (p.Val118Ala) of Snai1 confers consistently decreased risks of lung cancer and COPD, and this variant affects lung cancer risk through a mediation effect of COPD.

Polymorphism in mature microRNA-608 sequence is associated with an increased risk of nasopharyngeal carcinoma

Accumulative evidences indicated that microRNAs (miRNAs) can function as tumor suppressors and oncogenes, in which genetic variations are implicated in various cancer susceptibilities. However, it remains unclear whether single nucleotide polymorphisms (SNPs) in mature miRNA sequence alter nasopharyngeal carcinoma (NPC) susceptibility. In this study, we analyzed associations between eight SNPs in miRNA mature sequences (i.e., rs3746444T>C in hsa-mir-499, rs4919510C>G in hsa-mir-608, rs13299349G>A in hsa-mir-3152, rs12220909G>C in hsa-mir-4293, rs2168518G>A in hsa-mir-4513, rs8078913T>C in hsa-mir-4520a, rs11237828T>C in hsa-mir-5579, and rs9295535T>C in hsa-mir-5689) and NPC susceptibility in southern China with 906 NPC cases and 1072 cancer-free controls, and validated the significant findings in eastern China with 684 cases and 907 healthy controls. Functional assays were further performed to identify the biological effects of these polymorphisms. We found that rs4919510C>G polymorphism showed a consistent association with NPC risk in southern China (GC+GG versus CC genotype, odds ratio [OR]=1.36, 95% confidence interval [CI]=1.10-1.70) and eastern China (GC+GG versus CC: OR=1.37, 95% CI=1.08-1.74). After the two populations were merged, the ORs and 95% CI were 1.38 and 1.18 to 1.62, respectively. Moreover, the rs4919510C>G adverse genotypes significantly interacted with Epstein-Barr virus (EBV) infection on increasing NPC risk (P=0.001). The functional assay further showed that the CNE-2 cell lines that transfected with miR-608-rs4919510G allele expression vector exerted more colony number formations than cell lines that transfected with miR-608-rs4919510C allele expression vector (P=0.001). These data suggested that rs4919510C>G of miR-608 may be a susceptible biomarker of NPC in China.

The polymorphisms and haplotypes of WWOX gene are associated with the risk of lung cancer in southern and eastern Chinese populations.

The WW domain‐containing oxidoreductase (WWOX) gene is an identified tumor suppressor gene, of which several single nucleotide polymorphisms have been reported to contribute to cancer susceptibility. We hypothesized that genetic variations in WWOX are associated with lung cancer risk. In two independent case–control studies conducted in southern and eastern Chinese, we genotyped five tagSNPs of WWOX gene (rs10220974C > T, rs3764340C > G, rs12918952G > A, rs383362G > T, and rs12828G > A) in 1,559 lung cancer cases and 1,679 controls. Logistic regression analysis showed that two tagSNPs (rs3764340C > G; rs383362G > T) were significantly associated with lung cancer risk in dominant model (rs3764340C > G, GC/GG vs. CC: adjust OR = 1.35, 95% CI = 1.11–1.65; rs383362G > T, TG + TT vs. GG: adjust OR = 1.33, 95% CI = 1.14–1.55). The haplotype analysis further shown that the haplotype “G‐T” was associated with the highest increased risk of lung cancer (OR = 2.20; 95% CI = 1.43–3.37). After combined these two loci, the number of the risk genotypes was associated with increased cancer risk in a dose–response manner (Ptrend = 3.16 × 10−6). In addition, a gene‐based association analysis by using VEGAS software suggested the WWOX as a susceptible gene for lung cancer (P = 0.009). However, for rs10220974C > T, rs12918952G > A, and rs12828G > A, no significant association was observed for lung cancer risk. Taken together, our data suggested that genetic variants in WWOX may be genetic biomarkers for susceptibility to lung cancer. Copyright

Duplicated copy of CHRNA7 increases risk and worsens prognosis of COPD and lung cancer

Recent genome-wide association studies implicated that the nicotinic acetylcholine receptors (nAChRs) are common susceptible genes of two contextual diseases: chronic obstructive pulmonary disease (COPD) and lung cancer. We aimed to test whether the copy number variations (CNVs) in nAChRs have hereditary contributions to development of the two diseases. In two, two-stage, case–control studies of southern and eastern Chinese, a common CNV-3956 that duplicates the cholinergic receptor, nicotinic, α7 (CHRNA7) gene was genotyped in a total of 7880 subjects and its biological phenotype was assessed. The ≥4-copy of CNV-3956 increased COPD risk (≥4-copy vs 2/3-copy: OR=1.44, 95% CI=1.23–1.68) and caused poor lung function, and it similarly augmented risk (OR=1.49, 95% CI=1.29–1.73) and worsened prognosis (hazard ratio (HR)=1.25, 95% CI=1.07–1.45) of lung cancer. The ≥4-copy was estimated to account for 1.56% of COPD heritability and 1.87% of lung cancer heritability, respectively. Phenotypic analysis further showed that the ≥4-copy of CNV-3956 improved CHRNA7 expression in vivo and increased the carriers’ smoking amount. The CNV-3956 of CHRNA7 contributed to increased risks and poor prognoses of both COPD and lung cancer, and this may be a genetic biomarker of the two diseases.

The functional polymorphism of NBS1 p.Glu185Gln is associated with an increased risk of lung cancer in Chinese populations: Case-control and a meta-analysis

NBS1 plays pivotal roles in maintaining genomic stability and cancer development. The exon variant rs1805794G>C (p.Glu185Gln) of NBS1 has been frequently studied in several association studies. However, the results were conflicting. Also, the function of this variant has never been well studied. In the current study, we performed a two centers case-control study and function assays to investigate the effect of the variant rs1805794G>C on lung cancer risk in Chinese, and a meta-analysis to summarize the data on the association between rs1805794G>C and cancer risk. We found that compared with the rs1805794GG genotype, the C genotypes (CG/CC) conferred a significantly increased risk of lung cancer in Chinese (OR=1.40, 95% CI=1.21-1.62) and interacted with medical ionizing radiation exposure on increasing cancer risk (Pinteraction=0.015). The lymphocyte cells from the C genotype individuals developed more chromatid breaks than those from the GG genotype carriers after the X-ray radiation (P=0.036). Moreover, the rs1805794C allele encoding p.185Gln attenuated NBS1s ability to repair DNA damage as the cell lines transfected with NBS1 cDNA expression vector carrying rs1805794C allele had significantly higher DNA breaks than those transfected with NBS1 cDNA expression vector carrying rs1805794G allele (P<0.05). The meta-analysis further confirmed the association between the variant rs1805794G>C and lung cancer risk, that compared with the GG genotype, the carriers of C genotypes had a 1.30-fold risk of cancer (95% CI=1.14-1.49, P=8.49×10(-5)). These findings suggest that the rs1805794G>C of NBS1 may be a functional genetic biomarker for lung cancer.

A functional polymorphism in the promoter of ERK5 gene interacts with tobacco smoking to increase the risk of lung cancer in Chinese populations

Mitogen/extracellular signal-regulated kinase-5 (MEK5)/extracellular signal-regulated protein kinase-5 (ERK5) pathway plays a pro-oncogenic role in tumourigenesis by anticell apoptosis, promoting cell proliferation and differentiation in response to extracellular stimuli. As overexpressed MEK5/ERK5 is involved in the development of lung cancer, we hypothesised that the single nucleotide polymorphisms (SNPs) in MEK5 and ERK5 genes may influence gene expression and thus be associated with lung cancer risk. Five putative functional polymorphisms (rs3743353T>C, rs7172582C>T and rs2278076A>G of MEK5 and rs3866958G>T and rs2233083C>T of ERK5) were genotyped in two independent case-control studies with a total of 1559 lung cancer patients and 1679 controls in southern and eastern Chinese population. We found the rs3866958G>T of ERK5 was significantly associated with lung cancer risk, while other SNPs were not. Compared with the rs3866958TG/TT genotypes, the GG genotype conferred an increased risk of lung cancer (odds ratio = 1.30, 95% confidence interval = 1.12-1.51, P = 5.0×10(-4)), and this effect was more pronounced in smokers, accompanying with a significant interaction with smoking (P interaction = 0.013). The GG genotype also had significant higher mRNA levels of ERK5 in lung cancer tissues than TG/TT genotypes (P = 1.0×10(-4)); the luciferase reporter with the G allele showed significant higher transcription activities than the T allele, especially after the treatment with tobacco extract in vitro. Our data indicated that the functional polymorphism rs3866958G>T in ERK5 was associated with an increased lung cancer risk in smokers by virtue of the positive interaction with smoking on promoting the ERK5 expression, which might be a valuable indicator for predicting lung cancer risk in smokers.

The effect of functional MAPKAPK2 copy number variation CNV-30450 on elevating nasopharyngeal carcinoma risk is modulated by EBV infection

UNLABELLED Mitogen-activated protein kinase-activated protein kinase 2 (MAPKAPK2) is recognized as oncogenic and simulative role on tumorigenesis by virtue of abnormal expression in cancer including nasopharyngeal carcinoma (NPC). We hypothesized that the copy number variation (CNV)-30450, which duplicates the MAPKAPK2 promoter, may affect MAPKAPK2 expression and be associated with NPC risk. In two independent case-control panels of southern and eastern Chinese with a total of 1590 NPC patients and 1979 cancer-free controls, we investigated the association between CNV-30450 and NPC risk by genotyping the CNV-30450 with the TaqMan assay, and tested its biological effect. Consistent findings were observed in the two populations, that the increased copy number of CNV-30450 was associated with increased risk of NPC (3/4-copy versus 2-copy: odds ratio = 1.28, 95% confidence interval = 1.10-1.49), in which lies a biological mechanism that the adverse genotypes enhanced the promoter activity of MAPKAPK2 and elevated MAPKAPK2 expression. Moreover, the CNV-30450 adverse genotypes significantly interacted with Epstein-Barr virus (EBV) infection on increasing NPC risk (P = 0.035), and the genotype-phenotype correlation was only significant in EBV-positive cases (P = 0.037) but not in EBV-negative ones (P = 0.366). These data suggest that the functional CNV-30450 in the MAPKAPK2 promoter elevates the NPC risk with a modulation by EBV infection, which may be an indicator of susceptibility to NPC. SUMMARY This case-control study suggests that the functional CNV-30450 in the MAPKAPK2 promoter elevates the NPC risk with a modulation by EBV infection, which may be an indicator of susceptibility to NPC.

The Functional Copy Number Variation-67048 in WWOX Contributes to Increased Risk of COPD in Southern and Eastern Chinese

Abstract Recent studies have recognized the genetic variants in the WW domain-containing oxidoreductase (WWOX) gene as genetic determinants of lung function, reflecting that the WWOX gene may be a susceptible factor of chronic obstructive pulmonary disease (COPD), which characters as poor lung function. We have previously showed that the copy number variation-67048 (CNV-67048) of WWOX was associated with lung cancer risk. Here, we hypothesized that the CNV-67048 affects COPD susceptibility. Based on a two-stage case-control study with a total of 1791 COPD patients and 1940 controls of southern and eastern Chinese, we found that the loss genotypes (0-copy and 1-copy) of CNV-67048 harbored a significantly increased risk of COPD, with an odds ratio (OR) as 1.29 (1.11–1.49) when compared with the common 2-copy genotype. The pre-forced expiratory volume in one second (pre-FEV1) to pre-forced vital capacity (pre-FVC) of carriers with loss genotypes (0.729 ± 0.130) was significantly lower than carriers with 2-copy genotype (0.747 ± 0.124; p = 7.93 × 10−5). However, no significant difference was observed on pre-FEV1, pre-FVC and the annual decline of pre-FEV1 between the loss genotypes and 2-copy genotype carriers. Our data suggest that the loss genotypes of CNV-67048 in WWOX predispose their carriers to COPD, which might be a genetic biomarker to predict risk of COPD in Chinese.