Vascular endothelial growth factor -634G/C and vascular endothelial growth factor -2578C/A polymorphisms and lung cancer risk: a case-control study and meta-analysis

The pharmacological and biological importance of EZH2 signaling in lung cancer

Up to 18% of cancer-related deaths worldwide are attributed to lung tumor and global burden of this type of cancer is ascending. Different factors are responsible for development of lung cancer such as smoking, environmental factors and genetic mutations. EZH2 is a vital protein with catalytic activity and belongs to PCR2 family. EZH2 has been implicated in regulating gene expression by binding to promoter of targets. The importance of EZH2 in lung cancer is discussed in current manuscript. Activation of EZH2 significantly elevates the proliferation rate of lung cancer. Furthermore, metastasis and associated molecular mechanisms including EMT undergo activation by EZH2 in enhancing the lung cancer progression. The response of lung cancer to therapy can be significantly diminished due to EZH2 upregulation. Since EZH2 increases tumor progression, anti-cancer agents suppressing its expression reduce malignancy. In spite of significant effort in understanding modulatory function of EZH2 on other pathways, it appears that EZH2 can be also regulated and controlled by other factors that are described in current review. Therefore, translating current findings to clinic can improve treatment and management of lung cancer patients.

Mapping of novel loci involved in lung and colon tumor susceptibility by the use of genetically selected mouse strains

Two non-inbred mouse lines, phenotypically selected for maximal (AIRmin) and minimal (AIRmax) acute inflammatory response, show differential susceptibility/resistance to the development of several chemically-induced tumor types. An intercross pedigree of these mice was generated and treated with the chemical carcinogen dimethylhydrazine, which induces lung and intestinal tumors. Genome wide high-density genotyping with the Restriction Site-Associated DNA genotyping (2B-RAD) technique was used to map genetic loci modulating individual genetic susceptibility to both lung and intestinal cancer. Our results evidence new common quantitative trait loci (QTL) for those phenotypes and provide an improved understanding of the relationship between genomic variation and individual genetic predisposition to tumorigenesis in different organs.

Relationship between vascular endothelial growth factor -2578C > a gene polymorphism and lung cancer risk: a meta-analysis

BACKGROUND

Several reports were published on the relationship between the vascular endothelial growth factor (VEGF) -2578C > A gene polymorphism and lung cancer risk; however, the results are debatable. This meta-analysis was conducted to assess the relationship between VEGF -2578C > A gene polymorphism and lung cancer risk.

METHODS

The associated literatures were identified on the 1st of September 2018 from CBM-disc (China Biological Medicine Database) and PubMed.

RESULT

A total of 14 reports were recruited into our meta-analysis to assess the association between VEGF -2578C > A gene polymorphism and lung cancer susceptibility. There was a marked association between VEGF -2578C > A A allele / CC genotype and lung cancer risk in overall and Asian populations (overall populations: A allele: OR = 1.26, 95% CI: 1.08-1.46, P = 0.003; CC genotype: OR = 0.72, 95% CI: 0.54-0.95, P = 0.02; Asians: A allele: OR = 1.33, 95% CI: 1.15-1.55, P = 0.0002; CC genotype: OR = 0.68, 95% CI: 0.50-0.93, P = 0.01). However, VEGF -2578C > A gene polymorphism was not associated with the risk of lung cancer in Caucasians.

CONCLUSION

VEGF -2578C > A A allele / CC genotype is associated with the lung cancer susceptibility in Asians and in overall populations.

Association between VEGF Gene Polymorphisms and the Susceptibility to Lung Cancer: An Updated Meta-Analysis

BACKGROUND AND OBJECTIVE

The association between vascular endothelial growth factor (VEGF) gene polymorphisms (-2578C/A, +936C/T, and -460C/T) and lung cancer risk has been extensively studied in the last decades, but currently available results remain controversial or ambiguous. Therefore, we conducted a meta-analysis to assess whether the relationship between the VEGF gene and lung cancer susceptibility exists.

METHODS

The meta-analysis was conducted by searching the databases PubMed, Embase, and Web of Science covering all eligible studies published up to October 1, 2017. The pooled odds ratios (ORs) as well as their 95% confidence intervals (CIs) were utilized to evaluate the possible associations. Publication bias of relevant studies was examined via Begg's funnel plots and Egger's regression tests.

RESULTS

This meta-analysis included 13 published case-control studies covering 4477 patients with lung cancer and 4346 healthy controls, who had been accrued from December 1992 to July 2012. For the overall eligible data collected in our meta-analysis, it indicated that VEGF +936C/T, -460C/T, and -2578C/A polymorphisms did not correlate with the elevated lung cancer risk in all genetic comparison models. Moreover, VEGF +460T/C polymorphism was found to be significantly associated with susceptibility to lung cancer in these models (allele model: pooled OR = 1.12, 95% CI: 1.00-1.26, P = 0.184; homozygote model: pooled OR = 1.51, 95% CI: 1.12-2.03, P = 0.821), but no significant results were detected in Caucasian populations.

CONCLUSIONS

VEGF +936C/T, -460C/T, and -2578C/A polymorphisms were not associated with the risk of lung cancer. The VEGF +460T/C polymorphism might be a risk factor for lung cancer only in Asian populations.

Genetic polymorphisms and lung cancer risk: Evidence from meta-analyses and genome-wide association studies

A growing number of studies investigating the association between Single Nucleotide Polymorphisms (SNPs) and lung cancer risk have been published since over a decade ago. An updated integrative assessment on the credibility and strength of the associations is required. We searched PubMed, Medline, and Web of Science on or before August 29^th, 2016. A total of 198 articles were deemed eligible for inclusion, which addressed the associations between 108 variants and lung cancer. Among the 108 variants, 63 were reported to be significantly associated with lung cancer while the remaining 45 were reported non-significant. Further evaluation integrating the Venice Criteria and false-positive report probability (FPRP) was performed to determine the strength of cumulative epidemiological evidence for the 63 significant associations. As a result, 15 SNPs on or near 12 genes and one miRNA with strong evidence of association with lung cancer risk were identified, including TERT (rs2736098), CHRNA3 (rs1051730), AGPHD1 (rs8034191), CLPTM1L (rs401681 and rs402710), BAT3 (rs3117582), TRNAA (rs4324798), ERCC2 (Lys751Gln), miR-146a2 (rs2910164), CYP1B1 (Arg48Gly), GSTM1 (null/present), SOD2 (C47T), IL-10 (-592C/A and -819C/T), and TP53 (intron 6). 19 SNPs were given moderate rating and 17 SNPs were rated as having weak evidence. In addition, all of the 29 SNPs identified in 12 genome-wide association studies (GWAS) were proved to be noteworthy based on FPRP value. This review summarizes and evaluates the cumulative evidence of genetic polymorphisms and lung cancer risk, which can serve as a general and useful reference for further genetic studies.

The association of genetic polymorphisms of hypoxia inducible factor-1 alpha and vascular endothelial growth factor with increased risk of chronic obstructive pulmonary disease: A case-control study

Accumulated data over the years have suggested that hypoxia inducible factor-1 alpha (HIF-1α) and its downstream vascular endothelial growth factor (VEGF) gene may be linked with chronic obstructive pulmonary disease (COPD). This study aims to investigate the association of HIF-1α and VEGF genetic polymorphisms and their correlated risks with COPD. COPD patients (case group) and healthy individuals (control group) were recruited. DNA was extracted to detect HIF-1α and VEGF genetic polymorphisms. Basal lung volume and forced expiratory capacity in 1st second (FEV1)/forced vital capacity (FVC) and FEV₁/predicted value (pred)% were calculated. Genotype and allele distributions in HIF-1α and VEGF genes were analyzed. Kaplan-Meier curves and logistic regression model were used for analysis of survival and COPD risk factors. Haplotypes for HIF-1α rs11549465 and rs11549467 were analyzed. FEV₁/FVC and FEV1/pred% in the case group were lower than the control group. Frequencies of HIF-1α rs11549465 CT + TT genotype and T allele, and rs11549467 GA + AA genotype and A allele were higher in the case group than the control group. Patients with rs11549465 CT + TT had higher COPD risk than those with the CC genotype. Patients with rs11549467 GA + AA showed higher COPD risk and lower FEV₁/FVC and FEV₁/pred% than those with the GG genotype. Patients with HIF-1α TA haplotype showed higher COPD risk than those with the CG haplotype. Survival rate of patients with HIF-1α rs11549467 GG genotype was higher than those with the GA + AA genotype. HIF-1α rs11549467 polymorphism may be associated with COPD risk.

Different roles of myofibroblasts in the tumorigenesis of nonsmall cell lung cancer

Myofibroblasts play a critical role in the cancer cell growth, invasion, and tumor-associated vascularization during the carcinogenesis of nonsmall cell lung cancer (NSCLC), whereas the underlying molecular bases are not completely understood. We isolated Lin-negative, Sca1-low, and CD49e-high myofibroblasts from the NSCLC tissues of the patients and modified the levels of either transforming growth factor β 1 (TGFβ1) or vascular endothelial growth factor A (VEGF-A) in these cells. We found that coculture with TGFβ1-overexpressing myofibroblasts significantly decreased the NSCLC cell growth in an MTT assay through proliferation suppression rather than modulation of cell apoptosis, while significantly increased the NSCLC cell invasiveness in either a transwell migration assay or a scratch wound healing migration assay. However, modulation of TGFβ1 levels in myofibroblasts did not significantly alter vessel formation in a human umbilical vein endothelial cells (HUVECs) transwell collagen gel assay. On the other hand, overexpression of VEGF-A in myofibroblasts significantly increased vessel formation in the HUVECs transwell collagen gel assay. Together, these data suggest that myofibroblasts may regulate cancer cell growth and invasion through TGFβ1 but modulate cancer-associated neovascularization through VEGF-A. Hence, targeting different signaling pathways in myofibroblasts may delicately control NSCLC growth and invasion.

Bioinformatics Analyses of the Role of Vascular Endothelial Growth Factor in Patients with Non-Small Cell Lung Cancer

PURPOSE

This study was aimed to identify the expression pattern of vascular endothelial growth factor (VEGF) in non-small cell lung cancer (NSCLC) and to explore its potential correlation with the progression of NSCLC.

METHODS

Gene expression profile GSE39345 was downloaded from the Gene Expression Omnibus database. Twenty healthy controls and 32 NSCLC samples before chemotherapy were analyzed to identify the differentially expressed genes (DEGs). Then pathway enrichment analysis of the DEGs was performed and protein-protein interaction networks were constructed. Particularly, VEGF genes and the VEGF signaling pathway were analyzed. The sub-network was constructed followed by functional enrichment analysis.

RESULTS

Total 1666 up-regulated and 1542 down-regulated DEGs were identified. The down-regulated DEGs were mainly enriched in the pathways associated with cancer. VEGFA and VEGFB were found to be the initiating factor of VEGF signaling pathway. In addition, in the epidermal growth factor receptor (EGFR), VEGFA and VEGFB associated sub-network, kinase insert domain receptor (KDR), fibronectin 1 (FN1), transforming growth factor beta induced (TGFBI) and proliferating cell nuclear antigen (PCNA) were found to interact with at least two of the three hub genes. The DEGs in this sub-network were mainly enriched in Gene Ontology terms related to cell proliferation.

CONCLUSION

EGFR, KDR, FN1, TGFBI and PCNA may interact with VEGFA to play important roles in NSCLC tumorigenesis. These genes and corresponding proteins may have the potential to be used as the targets for either diagnosis or treatment of patients with NSCLC.

Role of five small nucleotide polymorphisms in the VEGF gene on the susceptibility to osteosarcoma and overall survival of patients

The present study aimed to investigate the association between five common small nucleotide polymorphisms (SNPs) in the VEGF gene and the risk of osteosarcoma. An additional aim was to investigate the role of these five SNPs on the prognosis of osteosarcoma. A total of 186 patients with osteosarcoma and 186 age- and sex-matched healthy controls were enrolled into the present study. A polymerase chain reaction-restriction fragment length polymorphism assay was conducted to determine the incidence of the VEGF-2578 C/A, -1156 G/A, +1612 G/A, +936 C/T and -634 G/C polymorphisms. Conditional logistic regression analyses revealed that individuals carrying the -634 GG genotype possessed a significantly increased risk of osteosarcoma, with an adjusted odds ratio [(95% confidence interval (CI)] of 2.00 (1.07-3.75). In the Cox proportional hazards model, subsequent to adjusting for potential confounding factors, patients with osteosarcoma carrying the -634 GG genotype were found to demonstrate a shorter overall survival time (hazard ratio, 3.10; 95% CI, 1.17-8.38). The VEGF-634 G/C polymorphism may therefore be used as a genetic marker for the prediction of the risk and clinical outcome of osteosarcoma.

rs833061 and rs699947 on promoter gene of vascular endothelial growth factor (VEGF) and associated lung cancer susceptibility and survival: a meta-analysis

Background

As 2 important SNPs located in the promoter region of VEGF gene, the roles of rs833061 (−460C>T) and rs699947 (−2578C>A) in lung cancer susceptibility and survival remain inconclusive and controversial.

Material/Methods

For better understanding of these 2 SNPs in lung cancer risk and survival, a meta-analysis was performed to pool findings of previous studies and to generate large-scale evidence.

Results

Based on the 10 eligible studies included, this study observed that the −460C>T polymorphism generally had no significant effect on lung cancer risk. However, subgroup analysis found that −460TT homozygote variant might confer significantly increased cancer risk for Asians (TT vs. CC: OR=1.69, 95% CI 1.08–2.63, p=0.02), but not in Caucasians. Similar results were observed in −2578C>A in Asians (AA vs. CC: OR=3.00, 95% CI 1.51–5.95, p=0.002; AA vs. AC: OR=3.15, 95% CI 1.00–9.91, p=0.05; AA vs. (AC+CC): OR=2.92, 95% CI 1.51–5.65, p=0.001). In lung cancer survival, 4 trials included had conflicting results. One found −460C>T polymorphism had no effect on survival, 1 observed risk increasing, while the remaining 2 observed risk decreasing. This inconsistency was closely related to the different therapeutic practices applied in different studies, the effects of which were significantly affected by VEGF expression.

Conclusions

−460TT and −2578AA homozygote might lead to significantly increased cancer risk for Asians, but the effects on survival remain to be explored. These 2 SNPs might be potential indicators of lung cancer risk for Asians and should be considered when planning chemotherapy and radiotherapy for lung cancer patients.

Association of the vascular endothelial growth factor -2578C/A polymorphism with cancer risk: A meta-analysis update

The vascular endothelial growth factor (VEGF) -2578C/A polymorphism has been previously reported to be associated with cancer risk; however, the results have been controversial. Therefore, the aim of the present study was to explore the association between the VEGF -2578C/A polymorphism with the cancer risk. A total of 37 case-control studies were identified. The pooled analysis showed that there was no association between VEGF -2578C/A and the risk of cancer, and the odds ratios (ORs) [with the corresponding 95% confidence intervals (95% CIs)] were 0.97 (0.91-1.04) for C vs. A, 0.94 (0.86-1.02) for CC vs. AA, 0.92 (0.80-1.06) for CA vs. AA, 0.96 (0.89-1.03) for CC/CA vs. AA and 0.97 (0.88-1.08) for CC vs. CA/AA. Subgroup analyses according to ethnicity, source of control and type of cancer showed that the VEGF -2578C/A polymorphism is associated with colorectal and lung cancers. Additionally, the polymorphism may decrease the risk of cancer in the Asian population. This VEGF polymorphism was not associated with a risk of cancer for the Caucasian [0.92 (0.76-1.11) for CC vs. AA] and African populations [1.31 (0.67-2.58) for CC vs. AA], and it was not associated with bladder [1.06 (0.74-1.53) for CC/AA] and breast cancers [1.01 (0.90-1.15) for CC/AA]. Therefore, the present meta-analysis indicates that VEGF -2578C/A may only be associated with the risk of colorectal cancer, lung cancer and the Asian population. More studies with larger sample sizes are required to provide more conclusive evidence.