Clinical implications of genetic variations in the VEGF system in relation to colorectal cancer

The Impact of ARMS2 (rs10490924), VEGFA (rs3024997), TNFRSF1B (rs1061622), TNFRSF1A (rs4149576), and IL1B1 (rs1143623) Polymorphisms and Serum Levels on Age-Related Macular Degeneration Development and Therapeutic Responses

Age-related macular degeneration (AMD) is a major global health problem as it is the leading cause of irreversible loss of central vision in the aging population. Anti-vascular endothelial growth factor (anti-VEGF) therapies are effective but do not respond optimally in all patients. This study investigates the genetic factors associated with susceptibility to AMD and response to treatment, focusing on key polymorphisms in the ARMS2 (rs10490924), IL1B1 (rs1143623), TNFRSF1B (rs1061622), TNFRSF1A (rs4149576), VEGFA (rs3024997), ARMS2, IL1B1, TNFRSF1B, TNFRSF1A, and VEGFA serum levels in AMD development and treatment efficacy. This study examined the associations of specific genetic polymorphisms and serum protein levels with exudative and early AMD and the response to anti-VEGF treatment. The AA genotype of VEGFA (rs3024997) was significantly associated with a 20-fold reduction in the odds of exudative AMD compared to the GG + GA genotypes. Conversely, the TT genotype of ARMS2 (rs10490924) was linked to a 4.2-fold increase in the odds of exudative AMD compared to GG + GT genotypes. In females, each T allele of ARMS2 increased the odds by 2.3-fold, while in males, the TT genotype was associated with a 5-fold increase. Lower serum IL1B levels were observed in the exudative AMD group compared to the controls. Early AMD patients had higher serum TNFRSF1B levels than controls, particularly those with the GG genotype of TNFRSF1B rs1061622. Exudative AMD patients with the CC genotype of TNFRSF1A rs4149576 had lower serum TNFRSF1A levels compared to the controls. Visual acuity (VA) analysis showed that non-responders had better baseline VA than responders but experienced decreased VA after treatment, whereas responders showed improvement. Central retinal thickness (CRT) reduced significantly in responders after treatment and was lower in responders compared to non-responders after treatment. The T allele of TNFRSF1B rs1061622 was associated with a better response to anti-VEGF treatment under both dominant and additive genetic models. These findings highlight significant genetic and biochemical markers associated with AMD and treatment response. This study found that the VEGFA rs3024997 AA genotype reduces the odds of exudative AMD, while the ARMS2 rs10490924 TT genotype increases it. Lower serum IL1B levels and variations in TNFRSF1B and TNFRSF1A levels were linked to AMD. The TNFRSF1B rs1061622 T allele was associated with better anti-VEGF treatment response. These markers could potentially guide risk assessment and personalized treatment for AMD.

Colon tumor CD31 expression is associated with higher disease-free survival in patients with metabolic syndrome

Metabolic syndrome (MS) is recognized as a risk factor for colon cancer (CC). However, how does the interplay between metabolic dysfunction caused by MS and its individual components affect CC microenvironment and prognosis remains unexplored. Angiogenesis and lymphangiogenesis are fundamental processes for tumor progression and dissemination, ensuring oxygen and nutrient delivery and supporting one of the most important pathways of tumor dissemination, contributing to metastasis. Thus, our aim was to evaluate whether the expression of molecular biomarkers involved in angiogenic and lymphangiogenic processes influenced CC clinicopathological features and prognosis in patients with MS. Clinical and pathological data of 300 patients submitted to CC surgical resection at a single tertiary hospital were retrospectively retrieved from hospital records. Tumor tissue microarrays of archived paraffin-embedded blocks were used to assess CD31, VEGF-A and D2-40 tissue expression by immunohistochemistry. The percentage of stained area was quantified by computerized morphometric analysis. No association between tissue expression of angiogenesis and lymphangiogenesis biomarkers and tumor clinical and pathological characteristics was found. However, in subgroup analysis of patients with MS, dysglycemia was associated with lower D2-40 expression (p = 0.007) and high waist-circumference was associated with higher D2-40 (p = 0.0029) and VEGF-A expression (p = 0.026). In an adjusted Cox proportional hazard model CD31 expression was significantly associated with greater disease-free survival (HR=0.62; 95% CI: 0.41-0.95, p = 0.028). No association was found between D2-40 and VEGF-A expression and CC prognosis. Our data reinforces previous reports that suggest the potential use of CD31 as a CC prognostic biomarker. Additionally, our data further supports the evidence for an interplay between metabolic dysfunction, tumor microenvironment, and vascularization pathways.

Relationship between EZH2 and VEGF expression and prognosis in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a common malignant tumor of the digestive system. However, its exact pathogenesis and independent prognostic factors are still unclear. In this study, we analyzed the expression of enhancer of zeste homolog 2 (EZH2) and vascular endothelial growth factor (VEGF) genes in CRC by using bioinformatics method and their relationship with prognosis. The expression of EZHE2 and VEGF proteins and their relationship with the patients' clinical characteristics were detected by immunohistochemistry.

AIM

To investigate the expression and mutation status of EZH2 and VEGF in CRC and their relationship with clinicopathological features and prognosis.

METHODS

The expression of EZH2 and VEGF genes in CRC and tumor adjacent tissues was compared in the TCGA database, and the mutations of EZH2 and VEGF genes were analyzed. The expression network of EZH2 and VEGF genes was established with the STRING database and the key genes in the network were screened. According to the expression of EZH2 and VEGF in tumor tissues, the patients were divided into high and low expression groups. Cox regression model and log-rank test were used to compare the difference of total survival and disease-free survival between the high and low expression groups. In addition, 80 patients with CRC who underwent surgery were selected, and their cancer tissues and adjacent tissues were collected. The expression of EZH2 and VEGF proteins in the above tissues was detected by immunohistochemistry.

RESULTS

Analysis based on the TCGA database showed that the expression levels of EZH2 and VEGF genes in CRC tissues were significantly higher than those in matched normal intestinal epithelial tissues (P < 0.05), but they had no significant correlation with clinical stage of CRC (P > 0.05).The mutation rates of EZH2 and VEGF genes in human CRC were 1.5% and 1.9%, respectively, and there were significant differences in the expression levels of EZH2 and VEGF mRNA in tissues with different EZH2 and VEGF mutation statuses. There are 22 proteins in the network. The average interaction index of each protein is 10.5, the regional aggregation index is 0.8, and the protein enrichment was obvious (P < 0.01). EZH2, DNMT1, HDAC2, YY1, and SUZ12 were screened as the key genes in the network using Cytohubb software. There was no correlation between the expression of EZH2 and VEGF and the total survival time of patients (P > 0.05), but the disease-free survival time of patients with high expression of VEGF was significantly lower than that of patients with low expression of VEGF (HR = 1.8, P < 0.05). Immunohistochemistry showed that the positive rates of EZH2 and VEGF proteins in CRC tissues were significantly higher than those in adjacent tissues (P < 0.01). The positive expression of EZH2 was related to tumor diameter, differentiation, and Duke stage (P < 0.05). The positive expression of VEGF was correlated with degree of differentiation and Duke stage (P < 0.05).

CONCLUSION

EZH2 and VEGF are up-regulated and mutated in CRC tissues. The high expression of EZH2 and VEGF is related to tumor size, differentiation, and Duke stage, and can be used as potential molecular markers for the prognosis of CRC.

Salt-Inducible Kinase 3 Haplotypes Associated with Noise-Induced Hearing Loss in Chinese Workers

INTRODUCTION

Noise-induced hearing loss (NIHL) is a common occupational disease that represents an irreversible hearing damage to the auditory system. It has been identified as a complicated disease involving both environmental and genetic factors. More efforts need to be made to explore the genes associated with susceptibility to NIHL. The main aim of this research is to detect the associations between SIK3 polymorphisms and NIHL susceptibility in Han people in China.

METHODS

A case-control study was performed in 586 cases and 639 controls in a textile factory matched for sex, age, smoking, drinking, work time with noise, and intensity of noise exposure. Three single nucleotide polymorphisms (SNPs) (rs493134, rs6589574, and rs7121898) of SIK3 were genotyped in the participants. Then, the main influences of the SNPs on and their interactions with NIHL were assessed.

RESULTS

Under the allelic model, distributions of rs493134 T, rs6589574 G, and rs7121898 A in the NIHL group are statistically different from those of the normal group (p = 0.001, p < 0.001, and p = 0.019, respectively). The following haplotype analysis shows that TAA (rs493134-rs6589574-rs7121898) may have a protective effect, while TGA (rs493134-rs6589574-rs7121898) (OR = 1.49, 95% CI = 1.25-1.79) may be a risk factor for NIHL. Multifactor dimensionality reduction analysis shows that the interaction of the 3 selected SNPs is associated with NIHL susceptibility (OR = 1.88, 95% CI = 1.50-2.36).

CONCLUSION

The results suggest that 3 SNPs (rs493134, rs6589574, and rs7121898) of SIK3 may be an important part of NIHL susceptibility and can be applied in the prevention, early diagnosis, and treatment of NIHL in noise-exposed Chinese workers.

Immunohistochemical Expression of Fatty Acid Synthase and Vascular Endothelial Growth Factor in Primary Colorectal Cancer: a Clinicopathological Study

BACKGROUND

Fatty acid synthase (FAS) is a valuable lipid enzyme involved in lipid biosynthesis and suggested to contribute in tumor carcinogenesis. Vascular endothelial growth factor (VEGF) is considered a serious angiogenic growth factor in the angiogenic pathway which is a very important in tumor growth and metastasis. Thus, inhibition of lipid biosynthesis and tumor angiogenesis can be new goals for colorectal cancer (CRC) treatment.

AIM OF THE WORK

The assessment of the expression of FAS and VEGF protein and the relationship between them in CRC with the clinicopathological parameters.

METHODS

The present retrospective study included 63 paraffin blocks previously diagnosed as primary cases of CRC. The slides were subjected to FAS and VEGF immunohistochemical staining using a streptavidin-biotin-peroxidase. The relationships among FAS and VEGF expression and clinicopathological parameters were statistically analyzed.

RESULTS

The expression rate of FAS was 81% and VEGF was 84.1% in the studied cases. FAS expression was significantly associated with histopathological type (p = 0.02) and grade (p = 0.04), and highly associated with lymph node metastasis and stage (p < 0.001).VEGF was significantly associated with histopathological type (p = 0.01) and tumor depth (p = 0.02); highly associated with grade, lymph node metastasis, and stage (p < 0.001). There was a positive association between FAS and VEGF expression in CRC (p < 0.001).

CONCLUSION

FAS and VEGF showed a highly significant expression in the studied primary CRC cases. A significant association was observed between their expressions, suggesting the involvement of FAS in tumor angiogenesis. So they constitute potential targets in cancer prevention and treatment and make FAS an attractive antiangiogenic target.

Overview of Current Immunotherapies Targeting Mutated KRAS Cancers

The occurrence of somatic substitution mutations of the KRAS proto-oncogene is highly prevalent in certain cancer types, which often leads to constant activation of proliferative pathways and subsequent neoplastic transformation. It is often seen as a gateway mutation in carcinogenesis and has been commonly deemed as a predictive biomarker for poor prognosis and relapse when conventional chemotherapeutics are employed. Additionally, its mutational status also renders EGFR targeted therapies ineffective owing to its downstream location. Efforts to discover new approaches targeting this menacing culprit have been ongoing for years without much success, and with incidences of KRAS positive cancer patients being on the rise, researchers are now turning towards immunotherapies as the way forward. In this scoping review, recent immunotherapeutic developments and advances in both preclinical and clinical studies targeting K-ras directly or indirectly via its downstream signal transduction machinery will be discussed. Additionally, some of the challenges and limitations of various K-ras targeting immunotherapeutic approaches such as vaccines, adoptive T cell therapies, and checkpoint inhibitors against KRAS positive cancers will be deliberated.

Genetic variants related to angiogenesis and apoptosis in patients with glioma

BACKGROUND

Glioma, the most common primary malignant brain tumor in adults, is highly aggressive and associated with a poor prognosis. The objectives of this study were to evaluate the association of genetic polymorphisms related to angiogenesis and apoptosis with gliomas, as well as comorbidities, lifestyle, clinical profile, survival and response to treatment (temozolomide [TMZ] and radiotherapy [RT]) in patients with the disease.

METHODS

In a total of 303 individuals, genotypes were performed by real-time PCR, and clinical data, lifestyle and comorbidities were obtained from medical records and questionnaires. The significance level was set at 5%.

RESULTS

Smoking, alcohol consumption, systemic arterial hypertension, diabetes mellitus and body mass index prevailed among patients, compared to controls (p < 0.05). The heterozygous genotype rs1468727 (T/C) and the homozygous genotype rs2010963 (G/G) (p > 0.05) were observed in both groups. Lifestyle and comorbidities showed independent risk factors for the disease (p < 0.0001, p = 0.0069, p = 0.0394, respectively). Patients with low-grade gliomas had a survival rate of 80.0 ± 1.7% in three years. For the combination of TMZ+RT, survival was 78.7 ± 7.6% in 20 months, compared to TMZ only (21.9 ± 5.1%, p = 0.8711).

CONCLUSIONS

Genetic variants were not associated with gliomas. Specific lifestyle habits and comorbidities stood out as independent risk factors for the disease. Low-grade gliomas showed an increase in patient survival with TMZ+RT treatment.

Association between single nucleotide variants of vascular endothelial growth factor A and the risk of thyroid carcinoma and nodular goiter in a Han Chinese population

The aim of the present study was to investigate whether genetic variants in the vascular endothelial growth factor A gene (VEGFA) were risk factors for papillary thyroid carcinoma (PTC) or nodular goiter (NG) in Han Chinese. A total of 2,319 subjects (861 PTC patients, 562 NG patients, and 896 healthy controls) were included. Five tag single nucleotide polymorphisms (tagSNPs: rs3024997, rs3025040, rs833070, rs25648, and rs10434) in VEGFA were genotyped. SNP rs3025040 T allele was associated with a decreased risk of NG (P<0.05). SNP rs3024997 was associated with an increased risk of PTC (P<0.05) and NG (P<0.001) when an over-dominant model (AA+GG vs. AG) was considered. PTC patients carry the less frequent TT genotype (compared to the CC genotype) (P <0.05) of SNP rs3025040. Likewise, NG patients have the less frequent TC genotype compared to the CC (P <0.05). No significant association of SNPs rs833070, rs25648, and rs10434 with PTC or NG was observed. Haplotypes AT (rs3024997 and rs3025040) and GTA (rs10434, rs3025040, and rs3024997) showed a lower risk for NG (P <0.01 and P <0.05, respectively), while haplotypes GTT (rs833070, rs3025040, and rs3024997) and GGGT (rs833070, rs10434, rs3024997, and rs3025040) predicted the risk of progression to NG (both P <0.05). Haplotype AGAC (rs833070, rs10434, rs3024997, and rs3025040) conferred protection for PTC (P <0.05). In summary, this study indicated for the first time that SNPs rs3024997 and rs3025040 in VEGFA were significantly associated with PTC and/or NG. Haplotypes of the VEGFA may influence the risk of PTC and NG.

Prognostic significance of vascular endothelial growth factor polymorphisms in colorectal cancer patients

AIM

To investigate the associations of the genetic polymorphisms of vascular endothelial growth factor A (VEGF-A) -1498C>T and -634G>C, with the survival of patients with colorectal cancer (CRC).

METHODS

A prospective cohort consisting of 131 Brazilians patients consecutively operated on with a curative intention as a result of sporadic colorectal carcinoma was studied. DNA was extracted from peripheral blood and its amplification and allelic discrimination for each genetic polymorphism was performed using the technique of polymerase chain reaction (PCR) in real-time. The real-time PCR technique was used to identify the VEGF-A -1498C>T (rs833031) and -634G>C (rs2010963) polymorphisms. Genotyping was validated for VEGF-A -1498C>T polymorphism in 129 patients and for VEGF-A -634G>C polymorphism in 118 patients. The analysis of association between categorical variables was performed using logistic regression, survival by Kaplan-Meier method and multivariate analysis by the Cox regression method.

RESULTS

In the univariate analysis there was a significant association (OR = 0.32; P = 0.048) between genotype CC of the VEGF-A -1498C>T polymorphism and the presence of CRC liver metastasis. There was no association between VEGF-A -1498C>T polymorphism and VEGF-A -634G>C polymorphism with further clinical or anatomopathologic variables. The genotype CC of the VEGF-A -1498C>T polymorphism was significantly correlated with the 5-year survival (P = 0.032), but not significant difference (P = 0.27) was obtained with the VEGF-A -634G>C polymorphism with the 5-year survival in the univariate analysis. The genotype CT (HR = 2.79) and CC (HR = 4.67) of the polymorphism VEGF-A -1498C>T and the genotype CC (HR = 3.76) of the polymorphism VEGF-A -634C>G acted as an independent prognostic factor for the risk of death in CRC patients.

CONCLUSION

The CT and CC genotypes of the VEGF-A -1498C>T and the CC genotype of the VEGF-A -634C>G polymorphisms are prognostic factors of survival in Brazilians patients with sporadic colorectal carcinoma.

Significant effect of VEGFA polymorphisms on the clinical outcome of metastatic colorectal cancer patients treated with FOLFIRI-cetuximab

AIM

The efficacy of a cetuximab-based regimen used to treat metastatic colorectal cancer (mCRC) could be influenced by VEGFA polymorphisms.

MATERIALS & METHODS

We studied the effects of five polymorphisms in the VEGFA gene (-2549D/I, -1154G/A, -460T/C, +405G/C and +936C/T) on the outcome of 98 mCRC patients treated with FOLFIRI plus cetuximab.

RESULTS

Patients homozygous for the -2549D, -1154G and -460T alleles did exhibit higher response rates to treatment and longer progression-free survival compared with others. In addition, the DGTGC and IGCGC haplotypes were significantly associated with a lower risk of disease progression.

CONCLUSION

These findings suggest that VEGFA genetic variations might influence response/resistance of FOLFIRI plus cetuximab treatment in mCRC patients.

Genetic Variants of VEGF (rs201963 and rs3025039) and KDR (rs7667298, rs2305948, and rs1870377) Are Associated with Glioma Risk in a Han Chinese Population: a Case-Control Study

A glioma is the most common type of brain tumor that accounts for nearly 80 % of brain cancers. Vascular endothelial growth factor (VEGF) and its receptor, the kinase insert domain receptor (KDR), are involved in the angiogenesis of cancers. In this study, we investigate whether the polymorphisms of VEGF and KDR are associated with a glioma risk. Blood samples were collected from 477 glioma patients and 477 healthy controls. Five tag-single nucleotide polymorphisms (SNPs) of KDR were obtained from the HapMap database, and eight tag-SNPs of VEGF were selected based on previous studies. After extraction of genomic DNAs by a Qiagen DNA blood kit, the SNPs of VEGF and KDR were genotyped with a Sequenom MassArray iPLEX platform and further analyzed with matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. The odds ratios and their 95% confidence interval (95% CI) were used to assess the association between VEGF, KDR polymorphisms, and glioma risks with the aid of SPSS 13.0 software. The haplotype analysis demonstrated that two SNPs of VEGF [rs3025039 (C>T), rs2010963 (G>C)] could elevate the susceptibility to a glioma in the homozygous model [odds ratio (OR) = 3.13 (95% confidence interval (CI) 1.30-7.49, P = 0.007) and OR = 1.58 (95% CI 1.07-2.34, P = 0.022), respectively], dominant model [OR = 1.38 (95% CI 1.04-1.84, P = 0.025) and OR = 1.32 (95% CI 1.01-1.72, P = 0.043), respectively], and allelic model [OR = 1.43 (95% CI 1.11-1.84, P = 0.005) and OR = 1.24 (95% CI 1.04-1.50, P = 0.019), respectively]. Furthermore, three SNPs of KDR [rs7667298 (A>G), rs2305948 (C>T), rs1870377 (T>A)] were also assumed to be associated with an increased risk of a glioma in the homozygous [OR = 1.93 (95% CI 1.30-2.86, P = 0.001), OR = 2.56 (95% CI 1.28-5.11, P = 0.006), and OR = 1.52 (95% CI 1.00-2.31, P = 0.049), respectively], dominant [OR = 1.52 (95% CI 1.16-1.98, P = 0.002), OR = 1.41 (95% CI 1.05-1.87, P = 0.020), and OR = 1.48 (95% CI 1.13-1.93, P = 0.004), respectively], and allele models [OR = 1.39 (95% CI 1.15-1.67, P = 0.001), OR = 1.47 (95% CI 1.14-1.89, P = 0.002), and OR = 1.27 (95% CI 1.05-1.52, P = 0.013), respectively]. The genetic polymorphisms of VEGF [rs3025039 (C>T), rs2010963 (G>C)] and KDR [rs7667298 (A>G), rs2305948 (C>T), rs1870377 (T>A)] increased glioma susceptibility in a Chinese population, suggesting the possibility of VEGF and KDR as genetic markers for glioma. Additional functional and association studies with different ethnic groups included are needed to further confirm our results.

Association between Polymorphisms in Vascular Endothelial Growth Factor Gene and Response to Chemotherapies in Colorectal Cancer: A Meta-Analysis

Background

Some studies have investigated the effects of polymorphisms in the vascular endothelial growth factor (VEGF) gene on responsiveness to chemotherapy for colorectal cancer (CRC) and have shown inconclusive results.

Methods

Eligible studies that assessed the associations between polymorphisms in the VEGF gene and response to chemotherapy in CRC were searched in the PubMed, Embase and Medline databases until November 2014. Odds ratios (OR) and 95% confidence intervals (CIs) were used to evaluate the associations, using Review Manager software, version 5.3. Stratified analysis was also conducted.

Results

In the overall analysis, a significant association with responsiveness to chemotherapy in CRC was identified in CC vs. CA of the VEGF -2578 C/A polymorphism (OR = 1.40, 95% CI 1.00-1.97, P = 0.05) and in CC+CT vs. TT of the VEGF -460 C/T polymorphism (OR = 0.71, 95% CI 0.53-0.96, P = 0.02). In subgroup analysis, a significant association was found in excluding anti-angiogenic agent subgroup in three comparison models of the VEGF -2578 C/A polymorphism and another three genetic models of the VEGF -460 C/T C/A polymorphism.

Conclusions

CC vs. CA of the VEGF -2578 C/A polymorphism and CC+CT vs. TT of the VEGF -460 C/T polymorphism might be predictive factors of responsiveness to chemotherapy in CRC. However, single-nucleotide polymorphisms in the VEGF gene lacked sufficient predictive ability to determine whether patients with CRC should add anti-angiogenic agents to their chemotherapy regimens.

Association of vascular endothelial growth factor--a gene polymorphisms and haplotypes with breast cancer metastases

BACKGROUND

Vascular endothelial growth factor (VEGF-A) is a key regulator of tumor-induced angiogenesis and essential for tumor growth and distant tumor spread. The aim of the present study was to evaluate the role of VEGF-A polymorphisms and haplotypes for metastatic progression in breast cancer patients.

MATERIAL AND METHODS

We performed a prospective study including 801 breast cancer patients. Occurrence of metastases was examined in regular follow-up investigations. Seven VEGF-A polymorphisms were selected and determined by 5'-nuclease assays (TaqMan). The selection of VEGF-A variants was based upon their location (promoter or UTR) as well as a minor allele frequency of at least 0.10. Haplotypes and linkage disequilibrium were determined using the Haploview program.

RESULTS

Within a median follow-up time of 84 months, 165 (21%) patients developed distant metastases. In univariate analysis, carriers of the CCCCC haplotype formed by five polymorphisms upstream the coding region were at decreased risk of distant metastases [hazard ratio (HR)=0.743; 95% CI 0.579-0.953; p=0.019]. Univariate analysis also revealed a decreased risk of distant metastases for postmenopausal patients carrying the -634G>C polymorphism (HR 0.704; 95% CI 0.514-0.965; p=0.029) and the CCCCC haplotype (HR=0.645; 95% CI 0.464-0.898; p=0.009). After adjustment for other co-variates, the HR for distant metastases was 0.651 (95% CI 0.447-0.948) for postmenopausal carriers of the -634G>C polymorphism (p=0.025; corrected p-value=0.262), and 0.586 (95% CI 0.393-0.873) for postmenopausal patients with the CCCCC haplotype (p=0.009, corrected p-value=0.189).

CONCLUSION

The results from univariate and multivariate analyses suggest an influence of VEGF-A gene variants on the development of distant metastases in breast cancer patients. However, none of the observed associations reached statistical significance after correction for the effects of multiple testing. Additional prospective and sufficiently powered studies are essential before firm conclusions about the role of VEGF-A gene variants for distant progression in breast cancer can be drawn.

Interplay between 3'-UTR polymorphisms in the vascular endothelial growth factor (VEGF) gene and metabolic syndrome in determining the risk of colorectal cancer in Koreans

Background

Polymorphisms in angiogenesis-related genes and metabolic syndrome (MetS) risk factors play important roles in cancer development. Moreover, recent studies have reported associations between a number of 3′-UTR polymorphisms and a variety of cancers. The aim of this study was to investigate the associations of three VEGF 3′-UTR polymorphisms (1451C > T [rs3025040], 1612G > A [rs10434], and 1725G > A [rs3025053]) and MetS with colorectal cancer (CRC) susceptibility in Koreans.

Methods

A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of VEGF polymorphisms was performed by TaqMan allelic discrimination assays. Cancer risks of genetic variations and gene-environment interactions were assessed by adjusted odds ratios (AORs) and 95% confidence intervals (CIs) of multivariate logistic regression analyses.

Results

VEGF 1451C > T was significantly associated with rectal cancer risk (Dominant model; AOR =1.58; 95% CI = 1.09 - 2.28; p = 0.015) whereas VEGF 1725G > A correlated with MetS risk (Dominant model; AOR =1.61; 95% CI =1.06 - 2.46; p = 0.026). Of the gene-environment combined effects, the interaction of VEGF 1451C > T and MetS contributed to increased rectal cancer risk (AOR = 3.15; 95% CI = 1.74 - 5.70; p < .001) whereas the combination of VEGF 1725G > A and MetS was involved with elevated colon cancer risk (AOR = 2.68; 95% CI = 1.30 - 1.55; p =0.008).

Conclusions

Our results implicate that VEGF 1451C > T and 1725G > A may predispose to CRC susceptibility and the genetic contributions may be varied with the presence of MetS.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-881) contains supplementary material, which is available to authorized users.

What could Nintedanib (BIBF 1120), a triple inhibitor of VEGFR, PDGFR, and FGFR, add to the current treatment options for patients with metastatic colorectal cancer?

Increasing knowledge of the pro-angiogenic processes involved in the progression of metastatic colorectal cancer (mCRC) has resulted in the clinical development of several anti-angiogenic agents, with bevacizumab currently being the only approved agent for mCRC. Nintedanib (BIBF 1120) has been shown to block the vascular endothelial growth factor receptor (VEGFR), the platelet-derived growth factor receptor (PDGFR), and the fibroblast growth factor receptor (FGFR). By targeting FGFR signaling, nintedanib may overcome resistance to previous anti-VEGF treatments, and may represent a better approach in patients with high basal levels of circulating FGFs. In this article, the angiogenic mechanisms implicated in mCRC are reviewed (focusing on the signaling pathways activated by VEGFR, PDGFR, and FGFR), along with the clinical data for nintedanib in the context of other anti-angiogenic tyrosine kinase inhibitors under clinical development for mCRC. Biomarkers that could predict response to nintedanib are also discussed.

FOLFIRI® and bevacizumab in first-line treatment for colorectal cancer patients: safety, efficacy and genetic polymorphisms

BACKGROUND

Over 50% of colorectal cancer (CRC) patients develop metastases. The aim of this study was to evaluate efficacy and tolerance of first-line FOLFIRI® + bevacizumab (B) treatment for metastatic CRC, and to assess genetic polymorphisms as potential markers.

METHODS

Adult patients with histologically-proven, non-resectable metastatic CRC and ECOG ≤ 2 were included. 14-day cycles consisted of bevacizumab (5 mg/kg), irinotecan (180 mg/m2), bolus FU (400 mg/m2) and leucovorin (400 mg/m2), followed by 46-hour FU infusions (2400 mg/m2). Primary endpoint was response rate according to RECIST criteria. Secondary endpoints were overall (OS) and progression-free (PFS) survivals, response duration, and toxicity. Associations between clinical data, UGT1A1, thymidylate synthase, VEGFA polymorphisms and PFS, OS and toxicity were analyzed.

RESULTS

Sixty-two patients were enrolled (median age 68y). 59/62 patients were eligible and evaluable for response at 6 months: 28 showed partial response (47.5%; 95% CI; 34.3-60.9), 20 stable disease (33.9%) and 11 progression (18.6%). Grade 3/4 toxicities were as follows: neutropenia 16.1%; diarrhea 11.3%; nausea-vomiting 1.6%. Median response duration was 9.5 months (range 2.7-20); median PFS 10.3 months (range 8.8-11.7); and median OS 25.7 months (range 20.2-29.7). 11/59 initially unresectable patients were resectable after treatment. VEGFA polymorphism (rs25648) was associated with better OS (HR: 3.61; 95% CI: 1.57-8.30).

CONCLUSIONS

FOLFIRI® + bevacizumab is active with good response rate, long median OS, and a good safety profile. A VEGFA polymorphism might have a prognostic value in this malignancy.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT00467142 (registration date: April 25, 2007).

Subcutaneous preconditioning increases invasion and metastatic dissemination in mouse colorectal cancer models

Mouse colorectal cancer (CRC) models generated by orthotopic microinjection of human CRC cell lines reproduce the pattern of lymphatic, haematological and transcoelomic spread but generate low metastatic efficiency. Our aim was to develop a new strategy that could increase the metastatic efficiency of these models. We used subcutaneous implantation of the human CRC cell lines HCT116 or SW48 prior to their orthotopic microinjection in the cecum of nude mice (SC+ORT). This subcutaneous preconditioning significantly enhanced metastatic dissemination. In the HCT116 model it increased the number and size of metastatic foci in lymph nodes, lung, liver and peritoneum, whereas, in the SW48 model, it induced a shift from non-metastatic to metastatic. In both models the number of apoptotic bodies in the primary tumour in the SC+ORT group was significantly reduced compared with that in the direct orthotopic injection (ORT) group. Moreover, in HCT116 tumours the number of keratin-positive tumour buddings and single epithelial cells increased at the invasion front in SC+ORT mice. In the SW48 tumour model, we observed a trend towards a higher number of tumour buds and single cells in the SC+ORT group but this did not reach statistical significance. At a molecular level, the enhanced metastatic efficiency observed in the HCT116 SC+ORT model was associated with an increase in AKT activation, VEGF-A overexpression and downregulation of β1 integrin in primary tumour tissue, whereas, in SW48 SC+ORT mice, the level of expression of these proteins remained unchanged. In summary, subcutaneous preconditioning increased the metastatic dissemination of both orthotopic CRC models by increasing tumour cell survival and invasion at the tumour invasion front. This approach could be useful to simultaneously study the mechanisms of metastases and to evaluate anti-metastatic drugs against CRC.

PDGFRα/β and VEGFR2 polymorphisms in colorectal cancer: incidence and implications in clinical outcome

Background

Angiogenesis plays an essential role in tumor growth and metastasis, and is a major target in cancer therapy. VEGFR and PDGFR are key players involved in this process. The purpose of this study was to assess the incidence of genetic variants in these receptors and its potential clinical implications in colorectal cancer (CRC).

Methods

VEGFR2, PDGFRα and PDGFRβ mutations were evaluated by sequencing their tyrosine kinase domains in 8 CRC cell lines and in 92 samples of patients with CRC. Correlations with clinicopathological features and survival were analyzed.

Results

Four SNPs were identified, three in PDGFRα [exon 12 (A12): c.1701A>G; exon 13 (A13): c.1809G>A; and exon 17 (A17): c.2439+58C>A] and one in PDGFRβ [exon 19 (B19): c.2601A>G]. SNP B19, identified in 58% of tumor samples and in 4 cell lines (LS174T, LS180, SW48, COLO205), was associated with higher PDGFR and pPDGFR protein levels. Consistent with this observation, 5-year survival was greater for patients with PDGFR B19 wild type tumors (AA) than for those harboring the G-allele genotype (GA or GG) (51% vs 17%; p=0.073). Multivariate analysis confirmed SNP B19 (p=0.029) was a significant prognostic factor for survival, independent of age (p=0.060) or TNM stage (p<0.001).

Conclusions

PDGFRβ exon 19 c.2601A>G SNP is commonly encountered in CRC patients and is associated with increased pathway activation and poorer survival. Implications regarding its potential influence in response to PDGFR-targeted agents remain to be elucidated.

VEGF -634C/G genotype is predictive of long-term survival after treatment with a definitive 5-fluorouracil/cisplatin-based chemoradiotherapy in Japanese patients with esophageal squamous cell carcinoma

BACKGROUND

Reports have been accumulating that genetic properties are predictive of clinical response after and/or toxicity during cancer chemotherapy, but little information is available concerning effects on long-term survival. In this study, 49 Japanese patients with esophageal squamous cell carcinoma (ESCC) were followed up for 5 years after treatment with a definitive 5-fluorouracil (5-FU)/cisplatin (CDDP)-based chemoradiotherapy (CRT), and the effects of genotypes of vascular endothelial growth factor (VEGF) were retrospectively revaluated in terms of prediction of long-term survival.

METHODS

A course consisted of the continuous infusion of 5-FU at 400 mg/m(2)/day for days 1-5 and 8-12, the infusion of CDDP at 40 mg/m(2)/day on days 1 and 8, and radiation at 2 Gy/day on days 1 to 5, 8 to 12, and 15 to 19, with a second course repeated after a 2-week interval. The VEGF genotypes -1498T/C, -1154G/A, -634C/G, -7C/T, 936C/T, and 1612G/A were evaluated.

RESULTS

The complete response (CR) rate was 46.9% (23/49). The 5-year survival rate was 42.9 % (21/49). There were 7 patients with a CR, but survival of less than 5 years. They died from myocardial infarction (N=1), sudden cardiac death after suffering from heart failure (N=1), acute myeloid leukemia that developed from myelodysplastic syndromes (N=1), factors not specified (N=2), oropharynx cancer (N=1), and tongue cancer (N=1). VEGF -634C/G had no effect on clinical response, but long-term survival depended on the genotype (p=0.033, Fisher's; p=0.038, Cochran-Armitage; p=0.079, Log-rank). The genotype frequency of 7 patients with a CR, but survival of less than 5 years was different from that for the other 42 patients (p=0.032, Fisher's). None of the other 5 genotypes evaluated affected either clinical response or survival.

CONCLUSIONS

VEGF -634C/G is possibly predictive of long-term survival after treatment with a definitive 5-FU/CDDP-based CRT. Further clinical studies with a larger number of cases are needed to clarify the effects of this genotype.