Association of VEGF genetic polymorphisms with prostate carcinoma risk and clinical outcome

VEGFA gene variants are associated with breast cancer progression

Angiogenesis is recognized as a hallmark of cancer, and vascular endothelial growth factor (VEGF) is a key regulator of the angiogenic process and is related to cancer progression. Anti-VEGF therapy has been tried but with limited success and without useful stratification for angiogenesis markers. Further, the landscape of VEGF single nucleotide polymorphisms (SNPs) in breast cancer and their clinical relevance is not well studied, and their relation to tissue-based angiogenesis markers has not been explored. Here, we studied a selection of VEGFA SNPs in nontumor lymph nodes from a population-based breast cancer cohort (n = 544), and their relation to clinicopathologic variables, vascular tissue metrics, and breast cancer-specific survival. Two of the SNP candidates (rs833068GA genotype and rs25648CC genotype) showed associations with angiogenesis tissue markers, and the VEGFA rs833068GA genotype was associated with breast cancer-specific survival among ER-negative cases. We also found trends of association between the rs699947CA genotype and large tumor diameter and ER-negative tumors, and between the rs3025039CC genotype and large tumor diameter. Our findings indicate some associations between certain VEGF SNPs, in particular the rs833068GA genotype, and both vascular metrics and patient survival. These findings and their potential implications need to be validated by independent studies.

An Investigation of the Association Between Vascular Endothelial Growth Factor +405 G/C Polymorphism and Acute Liver Transplant Rejection in Iranian Liver Transplant Recipients

OBJECTIVES

Vascular endothelial growth factor is an endothelial-specific growth factor that promotes endothelial cell proliferation, differentiation, and survival; mediates endothelium-dependent vasodilatation; induces microvascular hyperpermeability; and participates in interstitial matrix remodeling. The aim of the present study was to investigate the association between +405 G/C polymorphism of vascular endothelial growth factor and the risk of liver rejection in liver transplant recipients.

MATERIALS AND METHODS

The present study included 124 patients with liver disease that led to liver transplant. There were 22 patients who experienced histologically proven acute liver rejection, and the other 102 patients showed no rejection. Both groups were matched for sex and age. The VEGF+405 G/C polymorphism was evaluated by the polymerase chain reaction-restriction fragment-length polymorphism method.

RESULTS

Our analyses showed no significant relationships between genotypes and alleles of +405 G/C and risk of acute liver transplant rejection.

CONCLUSIONS

Our report indicated that there was no association between the carrier states of +405 G/C gene polymorphism of vascular endothelial growth factor and acute rejection or nonrejection of liver transplant.

Clinical and Genetic Predictors of Priapism in Sickle Cell Disease: Results from the Recipient Epidemiology and Donor Evaluation Study III Brazil Cohort Study

INTRODUCTION

Priapism is the persistent and painful erection of the penis and is a common sickle cell disease (SCD) complication.

AIM

The goal of this study was to characterize clinical and genetic factors associated with priapism within a large multi-center SCD cohort in Brazil.

METHODS

Cases with priapism were compared to SCD type-matched controls within defined age strata to identify clinical outcomes associated with priapism. Whole blood single nucleotide polymorphism genotyping was performed using a customized array, and a genome-wide association study (GWAS) was conducted to identify single nucleotide polymorphisms associated with priapism.

MAIN OUTCOME MEASURE

Of the 1,314 male patients in the cohort, 188 experienced priapism (14.3%).

RESULTS

Priapism was more common among older patients (P = .006) and more severe SCD genotypes such as homozygous SS (P < .0001). In the genotype- and age-matched analyses, associations with priapism were found for pulmonary hypertension (P = .05) and avascular necrosis (P = .01). The GWAS suggested replication of a previously reported candidate gene association of priapism for the gene transforming growth factor beta receptor 3 (TGFBR3) (P = 2 × 10-4).

CLINICAL IMPLICATIONS

Older patients with more severe genotypes are at higher risk of priapism, and there is a lack of consensus on standard treatment strategies for priapism in SCD.

STRENGTHS & LIMITATIONS

This study characterizes SCD patients with any history of priapism from a large multi-center cohort. Replication of the GWAS in an independent cohort is required to validate the results.

CONCLUSION

These findings extend the understanding of risk factors associated with priapism in SCD and identify genetic markers to be investigated in future studies to further elucidate priapism pathophysiology. Ozahata M, Page GP, Guo Y, et al. Clinical and Genetic Predictors of Priapism in Sickle Cell Disease: Results from the Recipient Epidemiology and Donor Evaluation Study III Brazil Cohort Study. J Sex Med 2019;16:1988-1999.

The Role of Polymorphisms in Genes of PI3K/Akt Signaling Pathway on Prostate

Background and Objective: Increasing evidence suggested that polymorphisms in genes of PI3K/Akt pathway were closely related to prostate cancer (PCa) risk. Nevertheless, these results are controversial and inconclusive. Here, we conducted a comprehensive updated meta-analysis and systematic review to precisely illustrate the association between polymorphisms in genes of PI3K/Akt signaling pathway and PCa risk.

Materials and Methods: The gene set of PI3K/Akt pathway was referenced from the Kyoto Encyclopedia of Genes and Genomes (KEGG) website. Relevant studies were identified by the systematically researching on PubMed, Web of Science and Google Scholar databases up to October 1, 2017. The odds ratios (ORs) with a corresponding 95% confidential intervals (95%CIs) were applied to test their associations. All the analyses were conducted by using Stata 12.0 (Stata Corporation, USA).

Results: Finally, 38 articles comprising 62 case-control studies were enrolled for 13 polymorphisms in genes of PI3K/Akt pathway. However, overall results failed to present a positive association between polymorphisms in genes of PI3K/Akt pathway and PCa risk. Nevertheless, in the subgroup analysis by ethnicity, we identified that IL-6-rs1800795 polymorphism was associated with an increased risk of PCa for Caucasian individuals in dominant model (MM + MW vs. WW: OR = 1.245, 95%CI = 1.176-1.318, P < 0.001).

Conclusion: Our work suggests that polymorphisms in genes of PI3K/Akt Signaling Pathway are not risk factor for PCa. Further well-designed studies with larger samples and precise designs are demanded to corroborate our findings.

Association Between 12 Polymorphisms of VEGF/Hypoxia/Angiogenesis Pathway Genes and Risk of Urogenital Carcinomas: A Meta-Analysis Based on Case-Control Studies

Objective: Previous studies indicated potential associations between polymorphisms in genes of VEGF/hypoxia/angiogenesis pathway and risk of urogenital carcinomas However, the results were controversial and inconclusive. Here, we conducted an in-depth meta-analysis to investigate the precise associations between polymorphisms in VEGF/hypoxia/angiogenesis related genes and risk of urogenital carcinomas.

Methods: We searched PubMed, Web of Science, EMBASE, and Cochrane Library to identify all eligible publications. Pooled odds ratios (ORs) corresponding with the 95% confidence intervals (CIs) were calculated to evaluate their associations. Subgroup analysis was conducted to further ascertain such relationship and investigate sources of heterogeneity.

Results: In the end, a total of 96 case-control studies fulfilled the inclusion criteria were enrolled for 12 polymorphisms in 4 VEGF/hypoxia/angiogenesis related genes. The pooled results showed eNOS-rs2070744 polymorphism conferred a significantly increased overall risk of urogenital carcinomas in allele, homozygote, and recessive models, respectively. In addition, eNOS-Intron 4a/b VNTR polymorphism was identified related to an increased risk of urogenital carcinomas in recessive model. And VEGF-rs699947 polymorphism was also identified an increased risk of renal cell carcinoma (RCC) in allelic, heterozygote, dominant, homozygote, and recessive models.

Conclusion: To conclude, eNOS-rs2070744 and eNOS-Intron 4a/b VNTR polymorphisms are risk factors for urogenital carcinomas. VEGF-rs699947 polymorphism was also identified as an increased risk factor for renal carcinoma.

SNP and Haplotype Analysis of Vascular Endothelial Growth Factor (VEGF) Gene in Lung Cancer Patients of Kashmir

Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis involving tumor growth and metastasis. In this large case-control study, we investigated whether functional polymorphisms (+405C>G, +936C>T) in the VEGF gene are associated with the risk of lung cancer. The study investigates the association between variants of VEGF gene and lung cancer. We performed single nucleotide polymorphism (SNP), haplotype and linkage disequilibrium studies on 100 patients and 128 healthy controls with 2 SNPs in the VEGF gene. The results were analyzed using logistic regression models, adjusted for age and sex. No Significant association was detected between individual SNPs and lung cancer using all the models of inheritance (codominant, dominant, recessive, over dominant and additive) for finding an association between genotypes and the cancer risk. The P values obtained for two markers were non-significant (P>0.05). Haplotype analysis produced additional support for the non-association of individual haplotypes/all haplotypes with the cancer risk (Global association P=0.56). Our findings suggest the non-involvement of genetic variants (+405C>G, +936C>T) of the VEGF gene in the etiology of lung cancer.

The Androgen Receptor and VEGF: Mechanisms of Androgen-Regulated Angiogenesis in Prostate Cancer

Prostate cancer progression is controlled by the androgen receptor and new blood vessel formation, or angiogenesis, which promotes metastatic prostate cancer growth. Angiogenesis is induced by elevated expression of vascular endothelial growth factor (VEGF). VEGF is regulated by many factors in the tumor microenvironment including lowered oxygen levels and elevated androgens. Here we review evidence delineating hormone mediated mechanisms of VEGF regulation, including novel interactions between the androgen receptor (AR), epigenetic and zinc-finger transcription factors, AR variants and the hypoxia factor, HIF-1. The relevance of describing the impact of both hormones and hypoxia on VEGF expression and angiogenesis is revealed in recent reports of clinical therapies targeting both VEGF and AR signaling pathways. A better understanding of the complexities of VEGF expression could lead to improved targeting and increased survival time for a subset of patients with metastatic castration-resistant prostate cancer.

Biology and therapeutic implications of VEGF-A splice isoforms and single-nucleotide polymorphisms in colorectal cancer

Tumor growth, dissemination and metastasis are dependent on angiogenesis. The predominant vascular endothelial growth factor (VEGF) isoform that plays a major role in angiogenesis is VEGF-A. Indeed, VEGF-A is implicated in promoting angiogenesis of numerous solid malignancies, including colorectal cancer (CRC). A large body of preclinical and clinical evidence indicates that the expression of specific VEGF-A isoforms represents a predominant pro-angiogenic factor, which is associated with formation of metastases and poor prognosis in CRC patients. Different isoforms of human VEGF-A have been identified, all of which arise from alternative splicing of the primary transcript of a single gene. Notably, it has been recently demonstrated that expression of type 3 isoform pattern is significantly correlated with venous involvement in CRC as well as in progression to metastatic colorectal cancer (mCRC), although it remains unclear what proportion of CRC tumors express these isoforms. This review highlights the importance of investigating the genetic and the epigenetic variations in VEGF-A pathways in CRC, the functions of different VEGF-A isoforms and their potential application as prognostic markers and/or therapeutic targets. Better understanding of the mechanisms controlling angiogenesis in liver metastases is necessary to address the limitations of current anti-angiogenic therapies.

Single nucleotide polymorphisms, haplotype association and tumour expression of the vascular endothelial growth factor (VEGF) gene with lung carcinoma

VEGF contains several polymorphic sites known to influence its expression. We examined the possible association between+405(-634)C>G,+936C>T,-2578C>A and lung cancer in 199 Kashmiri patients and 401 healthy controls. VEGF+405CG,+936CT+TT and-2578CA genotypes were significantly associated with lung cancer risk compared to VEGF+405CC,+936CC and-2578AA+CC genotypes [OR=0.07 (0.04-0.13), P<0.0001, OR=0.36 (0.25-0.52), P<0.0001 and 0.08 (0.05-0.13), P<0.0001]. Haplotype analysis revealed that CGA and TGA haplotypes of VEGF gene conveys the risk for lung cancer [OR=0.18 (0.10-0.33), P<0.0001 and 0.07 (0.03-0.13), P<0.0001]. VEGF expression revealed non-significant association with the genotypes of the three SNPs. In conclusion, the SNPs examined appear to influence lung cancer susceptibility while as genotypes of the SNPs don't appear to have significant association with VEGF mRNA expression in lung tumours.

Association of vascular endothelial growth factor -634G/C and receptor for advanced glycation end products G82S gene polymorphisms with diabetic retinopathy

AIM

To investigate the association of receptor for advanced glycation end products (RAGE) G82S and vascular endothelial growth factor (VEGF) -634 G/C gene polymorphisms with diabetic retinopathy (DR).

METHODS

Our cross-sectional study included 61 diabetic patients, 12 of them had proliferative diabetic retinopathy (PDR), 15 had non proliferative diabetic retinopathy (NPDR), 34 had no diabetic retinopathy (NDR) and 61 healthy controls. Participants were tested for RAGE G82S and VEGF -634 G/C polymorphisms by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

We found a significant association between VEGF -634 G/C polymorphism and PDR as PDR patients had increased incidence of VEGF -634 CC genotype compared to NDR patients [odds ratio for CC vs (GC+GG)=6.5, 95% CI=1.5-27.8, P=0.021]. Also VEGF -634 CC genotype and C allele were significantly higher in the PDR than in NPDR patients, which is a novel finding in our study (P=0.024, 0.009 respectively). The mean triglycerides level was significantly higher in diabetic patients with CC genotype (P=0.01) as compared to patients with other genotypes. All cases and control subjects were of the same heterozygous RAGE 82G/S genotype.

CONCLUSION

Patients carrying VEGF -634 C polymorphism have a higher risk of PDR development, so VEGF -634 G/C polymorphism could be used as a predictive marker for PDR in diabetic patients. We could not find a significant association between RAGE G82S polymorphism and DR.

No associations of a set of SNPs in the Vascular Endothelial Growth Factor (VEGF) and Matrix Metalloproteinase (MMP) genes with survival of colorectal cancer patients

In this study, we aimed to investigate the associations of genetic variations within select genes functioning in angiogenesis, lymph‐angiogenesis, and metastasis pathways and the risk of outcome in colorectal cancer patients. We followed a two‐stage analysis: First, 381 polymorphisms from 30 genes (eight Vascular Endothelial Growth Factor (VEGF) and 22 Matrix Metalloproteinase [MMP] genes) were investigated in the discovery cohort (n = 505). Then, 16 polymorphisms with the lowest P‐value in this analysis were investigated in a separate replication cohort (n = 247). Genotypes were obtained using the Illumina^® HumanOmni‐1‐Quad (discovery cohort) and Sequenom MassArray^® (replication cohort) platforms. The primary outcome measure was overall survival (OS). Kaplan–Meier, univariate and multivariable Cox regression methods were used to test the associations between genotypes and OS. Four SNPs (rs12365082, rs11225389, rs11225388, and rs2846707) had the univariate analysis P < 0.05 in both the discovery and replication cohorts. These SNPs are in linkage disequilibrium with each other to varying extent and are located in the MMP8 and MMP27 genes. In the multivariable analysis adjusting for age, stage, and microsatellite instability status, three of these SNPs (rs12365082, rs11225389, rs11225388) were independent predictors of OS (P < 0.05) in the discovery cohort. However, the same analysis in the replication cohort did not yield statistically significant results. Overall, while the genetic variations in the VEGF and MMP genes are attractive candidates as prognostic markers, our study showed no evidence of associations of a large set of SNPs in these genes and overall survival of colorectal cancer patients in our study.

Role of +405C>G and +936C>T polymorphisms of the vascular endothelial growth factor gene and risk of esophageal cancer in the Kashmiri population

BACKGROUND

The gene for the vascular endothelial growth factor (VEGF), which promotes angiogenesis and permeability, is polymorphic. The aim of the present study was to evaluate the relationship between +936C>T and +404C>G polymorphism of VEGF with risk of esophageal cancer in the Kashmiri population in India.

MATERIALS AND METHODS

150 esophageal cancer patients and 150 unrelated healthy controls were genotyped for two VGEF SNPs (+405C/G, and +936C/T) using DNA extracted from prospectively collected blood samples by the PCR-RFLP method.

RESULTS

For the VEGF +936C>T polymorphism a significant association of CT and combined CT+TT genotypes was observed with increased risk of esophageal cancer (p=0.021; 0.024). For the +405C>G polymorphism we observed significantly increased frequency of GG genotype in cases as compared to controls and also the +405 GG Genotype was observed to have a two fold risk(OR=2.7356; 95%CI=1.1409- 6.5593; p=0.020). The combined genotypes of GG-CC and GG-CT of +405C>G and +936C>T were found to be significantly associated with increased risk of esophageal cancer (p=0.0376; 0.0099).

CONCLUSIONS

From the results of the present study a significant association of +936C>T and +405C>G polymorphisms with increased esophageal cancer risk exists in the Kashmiri population.

Impact of VEGF gene polymorphisms in elderly cancer patients: clinical outcome and toxicity

Vascular endothelial growth factors (VEGFs) are the key regulators in angiogenesis and have been shown to play a significant role in the progression and prognosis of angiogenesis-related diseases, such as cancer. VEGF inhibitors are a current pharmacological tumoral strategy. However, despite the strong association between aging and cancer incidence and progression, recent findings suggest impaired angiogenesis accompanied by a reduced expression of VEGF in cells derived from aging subjects. Specific variations of VEGF genes have been demonstrated to be genetic determinants for susceptibility, outcome and therapy response, especially for the solid tumors. Considering the complications present in frail elderly patients, analysis of VEGF genetic polymorphisms in these subjects may further help in tailoring an angiogenic pharmacological strategy, and in improving our ability to better understand prognosis during therapy-related to cancer.

Vascular endothelial growth factor polymorphisms and a synchronized examination of plasma and tissue expression in epithelial ovarian cancers

In this study, we have analyzed six genetic polymorphisms of the VEGF-A gene and correlated the genetic data with plasma and tissue expression of VEGF-A in epithelial ovarian carcinomas. A total of 130 cases including 95 malignant carcinomas, 17 low malignant potential and 18 benign tumours were studied. rs699947, rs833061, rs1570360, rs2010963, rs1413711 and rs3025039 were studied by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Plasma levels of VEGF-A were estimated by enzyme-linked immunosorbent assay (ELISA) and tissue expression of VEGF-A by immunohistochemistry (IHC). Four polymorphisms of the above excluding rs699947 and rs3025039 showed significant association with malignancy, and we observed the presence of positive correlation between haplotype CCGGCC and increased expression of VEGF-A in both plasma and tissues which also correlated with poor prognosis and recurrence suggesting a probable increase in resistance to treatment in such carriers. Highly upregulated tissue expression of VEGF-A was seen in all epithelial ovarian carcinomas with intensity of expression increasing from benign to malignant cases. ELISA data from our study showed an increase in circulating levels of VEGF-A in malignancies. VEGF-A plasma levels can be employed as a biomarker for high-grade malignancy in epithelial ovarian cancers alongside tissue expression and CA-125 levels. This study is unique due to the fact that a simultaneous analysis of plasma and tissue expression has been demonstrated and is a first such study in epithelial ovarian cancers and representing the Indian population (South-east Asian) synchronized with genetic polymorphism data as well.

Regulation of vascular endothelial growth factor in prostate cancer

Prostate cancer (PCa) is the most common malignancy affecting men in the western world. Although radical prostatectomy and radiation therapy can successfully treat PCa in the majority of patients, up to ~30% will experience local recurrence or metastatic disease. Prostate carcinogenesis and progression is typically an androgen-dependent process. For this reason, therapies for recurrent PCa target androgen biosynthesis and androgen receptor function. Such androgen deprivation therapies (ADT) are effective initially, but the duration of response is typically ≤24 months. Although ADT and taxane-based chemotherapy have delivered survival benefits, metastatic PCa remains incurable. Therefore, it is essential to establish the cellular and molecular mechanisms that enable localized PCas to invade and disseminate. It has long been accepted that metastases require angiogenesis. In the present review, we examine the essential role for angiogenesis in PCa metastases, and we focus in particular on the current understanding of the regulation of vascular endothelial growth factor (VEGF) in localized and metastatic PCa. We highlight recent advances in understanding the role of VEGF in regulating the interaction of cancer cells with tumor-associated immune cells during the metastatic process of PCa. We summarize the established mechanisms of transcriptional and post-transcriptional regulation of VEGF in PCa cells and outline the molecular insights obtained from preclinical animal models of PCa. Finally, we summarize the current state of anti-angiogenesis therapies for PCa and consider how existing therapies impact VEGF signaling.

Arab gene geography: From population diversities to personalized medical genomics

Genetic disorders are not equally distributed over the geography of the Arab region. While a number of disorders have a wide geographical presence encompassing 10 or more Arab countries, almost half of these disorders occur in a single Arab country or population. Nearly, one-third of the genetic disorders in Arabs result from congenital malformations and chromosomal abnormalities, which are also responsible for a significant proportion of neonatal and perinatal deaths in Arab populations. Strikingly, about two-thirds of these diseases in Arab patients follow an autosomal recessive mode of inheritance. High fertility rates together with increased consanguineous marriages, generally noticed in Arab populations, tend to increase the rates of genetic and congenital abnormalities. Many of the nearly 500 genes studied in Arab people revealed striking spectra of heterogeneity with many novel and rare mutations causing large arrays of clinical outcomes. In this review we provided an overview of Arab gene geography, and various genetic abnormalities in Arab populations, including disorders of blood, metabolic, circulatory and neoplasm, and also discussed their associated molecules or genes responsible for the cause of these disorders. Although studying Arab-specific genetic disorders resulted in a high value knowledge base, approximately 35% of genetic diseases in Arabs do not have a defined molecular etiology. This is a clear indication that comprehensive research is required in this area to understand the molecular pathologies causing diseases in Arab populations.

Genetic variation: effect on prostate cancer

The crucial role of androgens in the development of prostate cancer is well established. The aim of this review is to examine the role of constitutional (germline) and tumor-specific (somatic) polymorphisms within important regulatory genes of prostate cancer. These include genes encoding enzymes of the androgen biosynthetic pathway, the androgen receptor gene, genes that encode proteins of the signal transduction pathways that may have a role in disease progression and survival, and genes involved in prostate cancer angiogenesis. Characterization of deregulated pathways critical to cancer cell growth have lead to the development of new treatments, including the CYP17 inhibitor abiraterone and clinical trials using novel drugs that are ongoing or recently completed [1]. The pharmacogenetics of the drugs used to treat prostate cancer will also be addressed. This review will define how germline polymorphisms are known affect a multitude of pathways, and therefore phenotypes, in prostate cancer etiology, progression, and treatment.

Association of +405C>G and +936C>T polymorphisms of the vascular endothelial growth factor gene with sporadic breast cancer in North Indians

BACKGROUND

Vascular endothelial growth factor (VEGF), an endothelial cell specific mitogen, has been implicated as a critical factor influencing tumor related angiogenesis. The aim of present study was to evaluate the relationship between VEGF +936C>T and +405C>G polymorphisms of VEGF with risk of breast cancer in Punjab, India.

MATERIALS AND METHODS

We screened DNA samples of 192 sporadic breast cancer patients and 192 unrelated healthy, gender and age matched control individuals for VEGF +936C>T and +405C>G polymorphisms using the PCR-RFLP method.

RESULTS

For the VEGF +405C>G polymorphism, we observed significantly increased frequency of GG genotype in cases as compared to controls and strong association of +405GG genotype was observed with three fold risk for breast cancer (OR=3.07; 95%CI 1.41-6.65; p=0.003). For the +936C>T polymorphism, significant associations of CT and combined CT+TT genotypes were observed with elevated risk of breast cancer (p=0.021; 0.023). The combined genotype combinations of GG-CC and GG- CT of +405C>G and +936C>T polymorphisms were found to be significantly associated with increased risk of breast cancer (p=0.04; 0.0064).

CONCLUSIONS

The findings of the present study indicated significant associations of VEGF +936C>T and +405C>G polymorphisms with increased breast cancer risk in patients from Punjab, North India.

Association of vascular endothelial growth factor polymorphisms with clinical outcome of renal cell carcinoma patients

We investigated the association of three single nucleotide polymorphisms (SNPs) in VEGF gene with the prognosis of renal cell carcinoma (RCC) and its association with clinical characteristics of RCC, such as tumor stages, metastasis, and tumor size. Polymerase chain reaction (PCR) restriction fragment length polymorphism analysis was used to genotype specimens for three polymorphisms (-2578C/A, -1154G/A, and -634G/C) in the VEGF gene. Hazard ratios (HRs) and their confidence intervals (CIs) were used to analyze the association of three SNPs in the VEGF gene with survival time using a multivariate Cox proportional hazards model. Frequencies of VEGF-2578AA genotype and A allele were significantly higher in patients with III-IV tumor stage or larger tumor size when compared with CC genotype. Moreover, frequencies of VEGF-634CC genotype and C allele were significantly higher in patients with tumor size >4 cm when compared with -634GG genotype. By Cox proportional hazards model, patients carrying VEGF-2578AA genotype and A allele significantly increased the risk of death from RCC, with the adjusted HRs (95 % CI) of 2.23 (1.15-4.36) and 1.55 (1.11-2.17), respectively. Our study suggests that VEGF-2578C/A and VEGF-634G/C polymorphisms may have effects on the prognosis of RCC. This finding might help in clarifying the mechanisms of RCC development and progression.

Vascular endothelial growth factor gene polymorphism (-634G/C) and breast cancer risk

The aim of this meta-analysis was to assess if the -634G/C polymorphism represents a predisposition factor for the risk of breast cancer. We included eight published case-control studies, in which a total of 6,175 cancer cases and 6,421 cancer-free controls were included. Pooled ORs and 95 % CIs were calculated by the fixed effects model to evaluate the association of the -634G/C polymorphism and breast cancer risk. When all studies were pooled, we did not find statistical evidence of any significant association with overall breast cancer risk (ORBB vs. bb = 1.00, 95 % CI = 0.93-1.07, P = 0.999; ORBB + Bb vs. bb = 1.00, 95 % CI = 0.95-1.05, P = 0.999; ORBB vs. Bb + bb = 1.03, 95 % CI = 0.96-1.09, P = 0.984; ORallele B vs. allele b = 1.01, 95 % CI = 0.97-1.05, P = 0.998; ORBb vs. bb = 0.99, 95 % CI = 0.92-1.06, P = 0.992). In further stratified analyses by ethnicity and control source, no significant association was revealed. This study suggests that the -634G/C polymorphism does not appear to represent a risk factor for breast cancer.

Assessment of the associations between three VEGF polymorphisms and risk of prostate cancer

Vascular endothelial growth factor (VEGF) plays a crucial role in the regulation of angiogenesis and is involved in the development and metastasis of common cancers. There were several case-controls studies published to assess the associations of VEGF polymorphisms with risk of prostate cancer, but the findings were inconsistent. We performed a meta-analysis to provide a comprehensive assessment of the associations of three VEGF polymorphisms with risk of prostate cancer. The pooled odds ratio (OR) with 95% confidence interval (95% CI) was calculated to assess the associations. Eleven individual case-control studies with a total of 5,209 cases of prostate cancer and 5,233 controls were finally included into our meta-analysis. Overall, VEGF rs833061 polymorphism was not associated with risk of prostate cancer (T versus C, OR = 1.14, 95% CI 0.91-1.44, P = 0.26; TT versus CC, OR = 1.09, 95% CI 0.67-1.76, P = 0.74; TT versus

CC/CT

OR = 1.46, 95% CI 0.67-3.18, P = 0.34; TT/CT versus CC, OR = 1.08, 95% CI 0.82-1.43, P = 0.59). VEGF rs3025039 polymorphism was also not associated with risk of prostate cancer (T versus C, OR = 1.03, 95% CI 0.91-1.16, P = 0.66; TT versus CC, OR = 1.82 95% CI 0.16-20.53, P = 0.63; TT versus CC/CT, OR = 2.00, 95% CI 0.18-22.41, P = 0.57; TT/CT versus CC, OR = 0.72, 95% CI 0.38-1.36, P = 0.31). VEGF rs2010963 polymorphism was not associated with risk of prostate cancer under three models (C versus G, OR = 1.17, 95% CI 0.92-1.48, P = 0.20; CC versus GG, OR = 2.28, 95% CI 0.90-5.75, P = 0.08; CC versus GG/GC, OR = 1.57, 95% CI 0.67-3.68, P = 0.30). In conclusison, current data suggest that those three VEGF polymorphisms are not obviously associated with risk of prostate cancer.

The RTK/ERK pathway is associated with prostate cancer risk on the SNP level: a pooled analysis of 41 sets of data from case-control studies

Prostate cancer (PCa) is a malignant disease influencing numerous men worldwide every year. However, the exact pathogenesis and the genes, environment, and other factors involved have not been explained clearly. Some studies have proposed that cell signaling pathways might play a key role in the development and progression of PCa. According to our previous study, the RTK/ERK pathway containing nearly 40 genes was associated with PCa risk. On the basis of these genes, we conducted a meta-analysis with our own Chinese Consortium for Prostate Cancer Genetics (ChinaPCa) study and available studies in the databases to describe the association between the pathway and PCa on the SNP level. The results suggested that rs4764695/IGF1 (recessive model: pooled OR=0.92, 95%CI=0.852-0.994, P=0.034; I(2)=0%, P=0.042; allele analysis: pooled OR=0.915, 95%CI=0.874-0.958, P=0; I(2)=0%, P=0.424; codominant model: OR=0.835, 95%CI=0.762-0.916, P=0; I(2)=0%, P=0.684) and rs1570360/VEGF (recessive model: OR=0.596, 95%CI=0.421-0.843, P=0.003; I(2)=23.9%, P=0.269; codominant model: OR=0.576, 95%CI=0.404-0.820, P=0.002; I(2)=49.1%, P=0.140) were significantly associated with PCa. In subgroup analysis, the relationship was also found in Caucasians for IGF1 (dominant model: OR=0.834, 95%CI=0.769-0.904, P=0; allele analysis: OR=0.908, 95%CI=0.863-0.955, P=0; AA vs CC: OR=0.829, 95%CI=0.750-0.916, P=0; AC vs CC: OR=0.837, 95%CI=0.768-0.912, P=0). In addition, in Asians (allele analysis: OR=0.21, 95%CI=0.168-0.262, P=0) and Caucasians (recessive model: OR=0.453, 95%CI: 0.240-0.855, P=0.015; codominant model: OR=0.464, 95%CI=0.240-0.898, P=0.023) for VEGF, the association was significant. The results indicated that rs4764695/IGF1 and rs1570360/VEGF might play a key role in the development and progression of PCa. On the SNP level, we suggest that the study gives us a new view of gene-pathway analysis and targeted therapy for PCa.

Vascular endothelial growth factor single-nucleotide polymorphism in gallbladder cancer

BACKGROUND AND AIM

Angiogenesis plays a key role in growth, progression, and metastasis of various cancers. Vascular endothelial growth factor (VEGF) polymorphism has been associated with several cancers. Role of VEGF has not been reported in gallbladder cancer (GBC). Present study was designed to investigate the role of VEGF polymorphism in GBC and in other (benign) gallbladder diseases, that is chronic cholecystitis (CC) and xanthogranulomatous cholecystitis (XGC).

METHODS

Blood samples were collected from 195 GBC, 140 CC, and 47 XGC patients and 300 normal healthy controls. VEGF polymorphisms were investigated using amplification refractory mutation system polymerase chain reaction for g.43737830A>G and g.3437A>C, polymerase chain reaction-restriction fragment length polymorphism for c.*237C>T, and g.43736418delTinsG amplified by polymerase chain reaction.

RESULTS

At g.43737830A>G, GA genotype showed susceptibility (odds ratio [OR] = 1.65 and OR = 1.68) and GG genotype showed protective association (OR = 0.58 and OR = 0.50) with GBC and CC. Allele A of VEGF g.43737830A>G was risk associated with GBC and CC (OR = 1.48 and OR = 1.70), while G allele was risk protective for GBC and CC (OR = 0.67 and OR = 0.58). At g.3437A>C, genotype CA was risk protective for GBC (OR = 0.61). TT genotype of c.*237C>T was susceptible for GBC and CC (OR = 2.59 and OR = 3.48), while CC genotype was risk protective for GBC and CC (OR = 0.61 and OR = 0.34). T allele of c.*237C>T polymorphism was risk associated with GBC and CC (OR = 1.63 and OR = 2.90), while C allele was risk protective for GBC and CC (OR = 0.38 and OR = 0.28). Haplotype I-C-A-C was risk protective for GBC (OR = 0.27).

CONCLUSION

The present study suggests that c.*237C>T and g.43737830A>G polymorphisms are useful markers of susceptibility to GBC.

VEGF-A mRNA processing, stability and translation: a paradigm for intricate regulation of gene expression at the post-transcriptional level

Vascular Endothelial Growth Factor A (VEGF-A) is a potent secreted mitogen crucial for physiological and pathological angiogenesis. Post-transcriptional regulation of VEGF-A occurs at multiple levels. Firstly, alternative splicing gives rise to different transcript variants encoding diverse isoforms that exhibit distinct biological properties with regard to receptor binding and extra-cellular localization. Secondly, VEGF-A mRNA stability is regulated by effectors such as hypoxia or growth factors through the binding of stabilizing and destabilizing proteins at AU-rich elements located in the 3′-untranslated region. Thirdly, translation of VEGF-A mRNA is a controlled process involving alternative initiation codons, internal ribosome entry sites (IRESs), an upstream open reading frame (uORF), miRNA targeting and a riboswitch in the 3′ untranslated region. These different levels of regulation cooperate for the crucial fine-tuning of the expression of VEGF-A variants. This review will be focused on our current knowledge of the complex post-transcriptional regulatory switches that modulate the cellular VEGF-A level, a paradigmatic model of post-transcriptional regulation.

MicroRNA expression profile analysis reveals diagnostic biomarker for human prostate cancer

Prostate cancer is a highly prevalent disease in older men of the western world. MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression via posttranscriptional inhibition of protein synthesis. To identify the diagnostic potential of miRNAs in prostate cancer, we downloaded the miRNA expression profile of prostate cancer from the GEO database and analysed the differentially expressed miRNAs (DE-miRNAs) in prostate cancerous tissue compared to non-cancerous tissue. Then, the targets of these DE-miRNAs were extracted from the database and mapped to the STRING and KEGG databases for network construction and pathway enrichment analysis. We identified a total of 16 miRNAs that showed a significant differential expression in cancer samples. A total of 9 target genes corresponding to 3 DE-miRNAs were obtained. After network and pathway enrichment analysis, we finally demonstrated that miR-20 appears to play an important role in the regulation of prostate cancer onset. MiR-20 as single biomarker or in combination could be useful in the diagnosis of prostate cancer. We anticipate our study could provide the groundwork for further experiments.

SNP-SNP interaction network in angiogenesis genes associated with prostate cancer aggressiveness

Angiogenesis has been shown to be associated with prostate cancer development. The majority of prostate cancer studies focused on individual single nucleotide polymorphisms (SNPs) while SNP-SNP interactions are suggested having a great impact on unveiling the underlying mechanism of complex disease. Using 1,151 prostate cancer patients in the Cancer Genetic Markers of Susceptibility (CGEMS) dataset, 2,651 SNPs in the angiogenesis genes associated with prostate cancer aggressiveness were evaluated. SNP-SNP interactions were primarily assessed using the two-stage Random Forests plus Multivariate Adaptive Regression Splines (TRM) approach in the CGEMS group, and were then re-evaluated in the Moffitt group with 1,040 patients. For the identified gene pairs, cross-evaluation was applied to evaluate SNP interactions in both study groups. Five SNP-SNP interactions in three gene pairs (MMP16+ ROBO1, MMP16+ CSF1, and MMP16+ EGFR) were identified to be associated with aggressive prostate cancer in both groups. Three pairs of SNPs (rs1477908+ rs1387665, rs1467251+ rs7625555, and rs1824717+ rs7625555) were in MMP16 and ROBO1, one pair (rs2176771+ rs333970) in MMP16 and CSF1, and one pair (rs1401862+ rs6964705) in MMP16 and EGFR. The results suggest that MMP16 may play an important role in prostate cancer aggressiveness. By integrating our novel findings and available biomedical literature, a hypothetical gene interaction network was proposed. This network demonstrates that our identified SNP-SNP interactions are biologically relevant and shows that EGFR may be the hub for the interactions. The findings provide valuable information to identify genotype combinations at risk of developing aggressive prostate cancer and improve understanding on the genetic etiology of angiogenesis associated with prostate cancer aggressiveness.

WITHDRAWN: Single nucleotide polymorphisms, haplotype association and tumour expression of the vascular endothelial growth factor (VEGF) gene with lung carcinoma

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Polymorphism of VEGF-460C/T associated with the risk and clinical characteristics of lung cancer in Chinese population

Vascular endothelial growth factor (VEGF) is a major regulator of angiogenesis in the process of tumor growth and metastasis. Different VEGF gene polymorphisms have been shown to result in different VEGF protein expression in cancer cells and tumor angiogenic activity. We conducted a case-control study to evaluate the genetic effects of VEGF-460C/T polymorphism on the development of lung cancer. One hundred and twenty-six lung cancer patients and 160 sex-, age-, and ethnic-matched healthy controls were recruited for this study. The genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Odds ratios (ORs) and 95 % confidence intervals (CI) were calculated by logistic regression analysis. Our study showed that the TT genotype was associated with increased lung cancer risk than those with the CC (OR = 1.99, 95 % CI 1.05-3.77) or CT/CC (OR = 1.89, 95 % CI 1.17-3.06) genotype. Moreover, it was observed that the TT genotype associated with the advanced stage among lung cancer patients (TT vs. CC: OR = 3.09, 95 % CI 1.10-8.66). More studies are needed to detect VEGF-460C/T polymorphism and its association with lung cancer in different ethnic populations incorporated with environmental exposures.

Current Evidence on VEGF+405G/C Polymorphism and Malignancy Susceptibility: A Meta-Analysis Involving 30 Studies

The association of VEGF+405G/C (where VEGF is vascular endothelial growth factor) polymorphism and malignancy susceptibility attracts considerable attention because VEGF is one of the most potent angiogenic factors and plays a critical role in the onset and development of malignancy. However, the published findings remain inconclusive. In order to derive a more precise assessment of the association, we performed a meta-analysis including 30 published case-control studies from PubMed, Embase, and Ovid databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. In the pooled analyses, no significant association was found between VEGF+405G/C polymorphism and malignancy susceptibility in different genetic models (G-allele vs. C-allele: OR = 1.00, 95% CI: 0.93–1.07; CC vs. GG: OR = 1.01, 95% CI: 0.88–1.15; GC+CC vs. GG: OR = 1.00, 95% CI: 0.91–1.10; CC vs. GC+GG: OR = 1.01, 95% CI: 0.90–1.13). When stratified by ethnicity, a weak association between this polymorphism and malignancy susceptibility was found in African under allelic frequency comparison (OR = 0.65, 95% CI: 0.43–0.98) and dominant genetic model comparison (OR = 1.95, 95% CI: 1.09–3.50). In summary, although our meta-analysis indicated a weak association of VEGF+405G/C polymorphism with malignancy susceptibility in African, no persuasive evidence of association between the polymorphism and malignancy susceptibility was detected in the pooled analyses. Therefore, more studies with larger scale of participants, especially Africans, are required to further evaluate gene-environment interaction on this polymorphism and malignancy susceptibility.

Gene variants in the angiogenesis pathway and prostate cancer

Although the causes of prostate cancer are still unknown, numerous studies support the role of genetic factors in the development and progression of this disease. Single nucleotide polymorphisms (SNPs) in key angiogenesis genes have been studied in prostate cancer. In this review, we provide an overview of the current knowledge of the role of genetic variants in the angiogenesis pathway in prostate cancer risk and progression. Of the 17 prostate cancer genome-wide association studies (GWAS) conducted to date, only one identified disease-associated SNPs in a region of an angiogenesis pathway gene. An association was observed between aggressive disease and three intergenic SNPs (rs11199874, rs10749408 and rs10788165) in a region on chromosome 10q26 that encompasses FGFR2. The majority (27/32, 84.4%) of primary candidate gene studies reviewed had a small (n < 800, 20/32, 62.5%) to medium sample size (n = 800-2000, 7/32, 21.9%), whereas only five (15.6%) had a large sample size (n ≥ 2000). Results from the large studies revealed associations with risk and aggressive disease for SNPs in NOS2A, NOS3 and MMP-2 and risk for HIF1-α. Meta-analyses have so far been conducted on FGFR2, TGF-β, TNF-α, HIF1-α and IL10 and the results reveal an association with risk for SNPs in FGFR2 and TGF-β and aggressive disease for SNPs in IL-10. Thus, existing evidence from GWAS and large candidate gene studies indicates that SNPs from a limited number of angiogenesis pathway genes are associated with prostate cancer risk and progression.

Polymorphisms of VEGFA gene and susceptibility to hemorrhage risk of brain arteriovenous malformations in a Chinese population

AIM

To evaluate the influence of the vascular endothelial growth factor A (VEGFA) polymorphisms on risk of presentation with intracerebral hemorrhage (ICH).

METHODS

Nine selected VEGFA single-nucleotide polymorphisms (SNPs) were genotyped in 311 patients with brain arteriovenous malformations (BAVM) in a Chinese population. Associations between individual SNPs/haplotypes and the hemorrhage risk of BAVMs were evaluated using logistic regression analysis.

RESULTS

In the single-locus analysis, rs1547651 was associated with increased risk of ICH (adjusted OR=2.11, 95% CI=1.01-4.42 compared with the AA genotype). In particular, an increased risk for ICH was associated with this variant in female patients (adjusted OR=3.21, and 95% CI=0.99-10.36). Haplotype-based analyses revealed that haplotype 'GC' in block 1 and haplotype 'ACC' in block 2 were associated with a 30%-38% reduction in the risk of ICH in patients with BAVMs compared to the most common haplotype (P(sim)=0.033 and P(sim)=0.005, respectively). The protective effect of haplotype 'ACC' in block 2 was more evident in male patients and subjects with BAVMs of a size ≥3 cm (adjusted OR=0.57, 95% CI=0.34-0.97 and adjusted OR=0.57, 95% CI=0.31-0.86, respectively).

CONCLUSION

The results suggest that VEGFA gene variants may contribute to ICH risk of BAVM.

Vascular Endothelial Growth Factor Gene Polymorphisms and Risk of Cervical Intraepithelial Neoplasia

Objective:

To evaluate the association between 3 vascular endothelial growth factor (VEGF) gene polymorphisms and susceptibility of cervical intraepithelial neoplasia (CIN).

Materials and Methods:

This prospectively collected case-control study investigates three common VEGF gene polymorphisms (ie, VEGF −460 [rs833061], VEGF +405 [rs2010963], and VEGF +936 [rs3025039]) in 203 women with CIN and 209 healthy women by DNA pyrosequencing. Associations between polymorphisms and CIN risk are evaluated with univariate and multivariable models and haplotype analysis.

Results:

In a multivariable regression model, the variant VEGF +405C allele was associated (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.2-5.1], P = 0.02) with increased susceptibility of CIN independent of number of sexual partners (OR, 2.2; 95% CI, 1.1-4.6; P = 0.03) and smoking (OR, 3.3; 95% CI, 1.6-6.6; P = 0.001). The haplotype VEGF −460C - +405C - +936C was associated with an OR of 5.2 (95% CI, 1.2-52.7) for the susceptibility of CIN.

Conclusions:

The presence of the variant VEGF +405C allele and the haplotype VEGF −460C - +405C - +936C are independently associated with higher susceptibility of CIN.

Single nucleotide polymorphisms of the vascular endothelial growth factor gene associated with incidence of oral squamous cell carcinoma

BACKGROUND

  Vascular endothelial growth factor (VEGF) plays an important role in promoting angiogenesis and is overexpressed in several malignancies. Polymorphisms of the VEGF gene can alter VEGF protein expression, which may be biologically significant and account for heterogeneity in disease risk and outcome. The aim of this case-control study was to evaluate potential associations between single nucleotide polymorphisms (SNP) of the VEGF gene with susceptibility of oral squamous cell carcinoma (OSCC).

PATIENTS AND METHODS

Five VEGF SNP (-1154 G/A, +405 G/C, +936 C/T, -2578 C/A and -460 C/T) were determined in peripheral blood isolated from 80 patients with OSCC and from 40 age- and gender-matched healthy volunteers (RT-PCR).

RESULTS

The +936 T allele and the -2578 C/A SNP were expressed significantly more often in the OSCC-group (P=0.002; P<0.0001) where three associations between two SNPs (+936 and +405, -2578 and -1154, -460 and -2578) were found.

CONCLUSION

Our findings provide support that +936 T allele and -2578 C/A SNP of the VEGF gene alone or in combination with other SNP are associated with OSCC. The SNPs may be used as biomarker for the development of specialized anti-VEGF drugs. Further studies must confirm the value of preoperative genetic analysis for prognosis.

Genetic and epigenetic changes in human prostate cancer

Acquired or inherited genetic alterations either alone or in combination with epigenetic alterations are associated with prostate carcinogenesis and its progression toward advance metastatic or castration-resistant disease. A major objective of translational cancer research in post-genome era is to discover the repertoire of genetic and epigenetic variations associated with prostate cancer. Genome-wide association studies have been at least partially successful in identifying potential germline polymorphisms and allelic imbalances such as microsatellite instability and loss of heterozygosity associated with prostate cancer susceptibility. Epigenetic mechanisms such as DNA hyper- or hypomethylation and histone modifications are reversible genetic alterations which allow stable inheritance of cellular phenotypes without any changes in the DNA sequence or quantity. Epigenetic modifications can potentially be used for the molecular classification, detection, and risk assessment in prostate cancer. Chemical inhibitors of DNA methyltransferases and histone deacetylases have been used in different clinical trials and hold promise as novel chemotherapeutics to be effective alone or in combination with other therapeutic interventions in prostate cancer.

Hypoxia-Inducible Factor 1α Polymorphisms and Early-Stage Cervical Cancer

Background:

Human papillomavirus can stabilize and induce hypoxia-inducible factor 1α (HIF-1α) protein, which is associated with diminished response to treatment and poor prognosis for cervical cancer. Hypoxia-inducible factor 1α polymorphisms (1772C>T and 1790G>A) in the N-terminal transactivation domain generate significantly increased transcriptional activity and have been linked to poor outcome in various malignancies.

Objective:

The aim of this study was to analyze the possible influence of HIF-1α genetic polymorphisms on cancer susceptibility, tumor aggressiveness, and survival of patients with early-stage cervical cancer.

Methods:

One hundred ninety-nine patients with early-stage cervical cancer who were treated with surgical resection were retrospectively investigated. Hypoxia-inducible factor 1α 1772C>T and 1790G>A genetic polymorphisms were compared with 205 healthy subjects and correlated with the clinical outcome of patients with early-stage cervical cancer.

Results:

The risk of cervical cancer was not affected by HIF-1α 1772C>T and 1790G>A polymorphisms. However, lymph node metastasis was significantly increased in patients who had the 1790 variant (adjusted odds ratio, 5.01; 95% confidence interval, 1.05-23.88;P= 0.043). In survival analysis, HIF-1α 1772C>T and 1790G>A polymorphisms were not related to disease-free survival and overall survival.

Conclusions:

Although HIF-1α genetic polymorphisms had little association with cervical cancer risk and prognosis, individual variance of HIF-1α gene may be associated with cervical cancer invasiveness.

Meta-analysis of the association between VEGF-634 G>C and risk of malignancy based on 23 case-control studies

PURPOSE

The association between polymorphism of vascular endothelial growth factor (VEGF)-634 G>C and malignancy risk has been widely studied, and no conclusive result was available up to now.

METHODS

Twenty-three case-control studies with 21,917 individuals were included in this meta-analysis through searching the databases of Medline, Embase, and CNKI (up to October 1st, 2010). The odds ratio (OR) and 95% confidence interval (95%CI) were used to investigate the strength of the association.

RESULTS

Overall, the pooled analysis showed that there was no association between VEGF-634 G>C and risk of malignancy, and the ORs (95%CIs) were 0.98 (0.85-1.12) for GG versus CC, 1.03 (0.90-1.17) for GC versus CC, 1.00 (0.89-1.13) for G carrier versus CC, and 1.08 (0.94-1.23) for C carrier versus GG. Subgroup analyses according to ethnicity, source of control, type of cancer, and sample size were also performed, and results indicated that VEGF-634 G>C was not associated with risk of malignancy for neither Asians [1.06 (0.81-1.38) for GG vs. CC and 1.08 (0.84-1.39) for GC vs. CC] nor Caucasians [0.93 (0.83-1.05) for GG vs. CC and 0.98 (0.87-1.10) for GC vs. CC]. It was also not associated with risk of breast cancer [0.95 (0.81-1.12) for GG vs. CC], gastric cancer [0.93 (0.47-1.84) for GG vs. CC], and colorectal cancer [1.17 (0.93-1.47) for GG vs. CC].

CONCLUSIONS

This meta-analysis suggests that VEGF-634 G>C may be not associated with risk of malignancy. More studies with larger sample size were needed to provide more precise evidence.