Association of the VEGF 936C>T Polymorphism with FDG Uptake, Clinical, Histopathological, and Metabolic Response in Patients with Adenocarcinomas of the Esophagogastric Junction

Association of VEGFA polymorphisms with the risk of oesophageal cancer in Punjab, India: A case-control study

Background & objectives Vascular endothelial growth factor (VEGF) is one of the most important angiogenic factors which stimulates tumour progression induction of endothelial cell migration and division, inhibition of the apoptosis of endothelial cells, induction of serine protease activity and enhancement of vascular permeability. This study aimed to investigate the correlation of VEGF+405G/C,-7C/T and+936C/T polymorphisms with oesophageal cancer risk. Methods DNA samples of 464 subjects (231 sporadic oesophageal cancer affected individuals and 233 controls) were genotyped forVEGF+936C/T,+405G/C and-7C/T polymorphisms. VEGF+936C/T and +405G/C polymorphisms were genotyped by PCR-RFLP method whereas VEGF-7C/T polymorphism was genotyped using Amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Results CT genotype of VEGF-7C/T polymorphism was significantly associated with reduced risk of oesophageal cancer. VEGF-7C/T polymorphism was significantly associated with reduced risk of oesophageal cancer underdominant, co-dominant, over dominant and log-additive genetic models in total patients and in the female group. C+936G+405T-7 haplotype was significantly associated with decreased risk (P=0.01)of oesophageal cancer in total patients and also in the male group (P=0.02). Interpretation & conclusions In future, replication of the findings of the present study in a larger sample from different ethnic groups, along with functional analysis, may be insightful for the role of VEGFA polymorphisms in the pathogenesis of oesophageal cancer. Identification of the correlation of VEGF variants with specific therapy in oesophageal cancer may help in better selection of patients and monitoring treatment response in VEGF-therapy.

Esophageal cancer: Risk factors, genetic association, and treatment

The poor prognosis and rising incidence of esophageal cancer highlight the need for improved detection and prediction methods that are essential prior to treatment. Esophageal cancer is one of the most fatal malignancies worldwide, with a dramatic increase in incidence in the Western world occurring over the past few decades. Despite improvements in the management and treatment of esophageal cancer patients, the general outcome remains very poor for overall 5-year survival rates (∼10%) and 5-year postesophagectomy survival rates (∼15-40%). Esophageal cancer is often diagnosed during its advanced stages, the main reason being the lack of early clinical symptoms. In an attempt to improve the outcome of patients after surgery, such patients are often treated with neoadjuvent concurrent chemoradiotherapy (CCRT) in order to decrease tumor size. However, CCRT may enhance toxicity levels and possibly cause a delay in surgery for patients who respond poorly to CCRT. Thus, precise biomarkers that could predict or identify patients who may or may not respond well to CCRT can assist physicians in choosing the appropriate therapy for patients. Identifying susceptible gene and biomarkers can help in predicting the treatment response of patients while improving their survival rates.

Association Between microRNA-125a rs12976445 C>T Polymorphism and 18F-Fluorodeoxyglucose (18FDG) Uptake: Clinical and Metabolic Response in Patients with Non-Small Cell Lung Cancer

Background

MicroRNA-125a (miR-125a) has been involved with many diseases, such as hepatocellular carcinoma and inflammation. In this study, we aimed to investigate the molecular mechanism, including the potential regulator and signaling pathways, of vascular endothelial growth factor (VEGF).

Material/Methods

We divided the participants into 3 groups by rs12976445 genotype and performed chi-square tests to evaluate the differences between CC and CT+TT groups for sex, age, grading, pT category, metastases, and fludeoxyglucose F18 injection (¹⁸FDG) metabolism.

Results

We found all variables to be statistically significant. We searched the miRNA database online (www.mirdb.org) with the “seed sequence” located within the 3-prime untranslated region (3′ UTR) of the target gene and then validated VEGF to be the direct gene via luciferase reporter assay system. We also established the negative regulatory relationship between MiR-125a and VEGF by studying the relative luciferase activity. We conducted real-time polymerase chain reaction and Western blot analysis to study the mRNA and protein expression level of VEGF among different groups (CC=18, CT=8, TT=3) or cells treated with scramble control, miR-125a mimics, VEGF RNA, and MiR-125a inhibitors.

Conclusions

We validated the negative regulatory relationship between MiR-125a and VEGF and found that rs12976445 may function as a biomarker to predict metabolism of ¹⁸FDG.

Predictive role of host constitutive variants in neoadjuvant therapy of esophageal cancer

Chemoradiotherapy followed by surgery is at present the standard therapeutic approach for esophageal cancer (EC) in patients with resectable tumor. However, response to neoadjuvant therapy is characterized by a strong interpatient variability, and the identification of markers predictive of outcome is mandatory. In this review, taking into account the currently available literature, we report the impact that host genetic variables can have on EC neoadjuvant therapy. We mainly focused on the gene variants involved in the pharmacokinetics and pharmacodynamics of the common chemotherapeutic drugs used to treat EC patients, commented on the weakness of the present knowledge, and discussed the future strategies to achieve a more personalized and effective EC treatment.

Immediate tumor resection in patients with locally advanced gastroesophageal adenocarcinoma with nonresponse to chemotherapy after 4 weeks of treatment versus resection after completion of chemotherapy (OPTITREAT trial, DRKS00004668): study protocol for a randomized controlled pilot trial

Background

Neoadjuvant chemotherapy is a standard of care for patients with adenocarcinoma of the esophagus and stomach in Europe, but still only 20–40 % respond to therapy and the critical issue; how to treat nonresponding patients is still unclear. So far, there is no randomized trial evaluating the impact of early termination of neoadjuvant chemotherapy and immediate tumor resection in nonresponding patients with locally advanced gastroesophageal cancer on postoperative outcome. With this exploratory pilot trial, we want to get first estimates about the effect of discontinuation of chemotherapy with the aim to plan and conduct a further definitive trial.

Methods/design

OPTITREAT is designed as a single-center, randomized controlled pilot trial with two parallel study groups. Four weeks after starting neoadjuvant chemotherapy in all patients, clinical response will be assessed by endoscopy and endosonographic ultrasound. Then, nonresponding patients (n = 84) will be randomized in a 1:1 ratio to intervention group with stopping chemotherapy and immediate tumor resection or control group with completion of chemotherapy before surgery. Outcome measures are overall survival, R0 resection rate, perioperative morbidity and mortality, histopathological response, and quality of life. Statistical analysis will be based on the intention-to-treat population. Due to the study design as an explorative pilot trial, no formal sample size calculation was performed. The planned total sample size of 120 patients is considered ethical and large enough to show the feasibility and safety of the concept. First data on differences between the study groups in the defined endpoints will also be generated.

Discussion

Individualized therapy is of utmost interest in the treatment of locally advanced gastroesophageal adenocarcinoma as less than half of the patients show objective response to current chemotherapy regimens. The findings of the OPTITREAT trial will help to get first data about clinical response evaluation followed by immediate tumor resection in nonresponding patients after 4 weeks of neoadjuvant chemotherapy. Based on the results of this pilot study, a future confirmatory trial will be planned to prove efficacy and evaluate significance.

Trial registration

German Clinical Trial Register number: DRKS00004668

Genetic Variations of Kinase Inserts Domain Receptor (KDR) Gene Are Associated with the Risk of Astrocytomas

Astrocytomas is one of the most common central nervous system (CNS) tumors with high mortality rate. Kinase insert domain receptor (KDR) is involved in the regulation of tumor angiogenesis, migration, and vascular permeability. The aim of the study was to explore the relationship between KDR polymorphisms and risk of astrocytomas. Blood samples were collected from 157 astrocytomas patients and 160 healthy controls. Three tag-SNPs (rs2071559C/T, rs2305948T/C, and rs1870377A/T) were identified from the International HapMap Project Databases and genotyped using the method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). We evaluated the astrocytomas risk caused by individual SNPs and haplotype using odds ratios (ORs) and their 95 % confidence intervals (CIs). In the overall individual SNP analysis, the C allele of rs2071559 was correlated with an increased risk of astrocytomas. However, individuals with mutant allele A and genotype TA + AA of rs1870377 showed a protective effect against astrocytomas. Subgroup analysis based on WHO tumor grade revealed that the C allele of rs2071559 had more influence with the risk of astrocytomas in the grade III-IV (OR = 1.91) subgroup than the grade I-II (OR = 1.47) group. Genotype TT of rs2305948 was found to be significantly associated with susceptibility of astrocytomas only in the grade III-IV subgroup. The protective effect of rs1870377 did not reveal significant difference between the grade III-IV and grade I-II subgroups. Meanwhile, stratified analysis demonstrated that mutation of rs2071559 and rs2305948 could elevate the risk of astrocytomas more significantly in the subgroup of smokers than the nonsmokers. Interestingly, the protective effect of rs1870377 was more obvious in the nonsmokers than the smokers. Additionally, haplotype-specific analysis showed that haplotype CCT and CTT were related with an increased risk of astrocytomas. We found that individual with variants of rs2071559*C and rs2305948*T might significantly elevate the risk of astrocytomas, while mutants of rs1870377*A was associated with the decreased risk of astrocytomas. Further studies about ethnically diverse populations with larger sample size should be performed to confirm the correlation between KDR gene polymorphisms and risk of astrocytomas.

The Association Between VEGF +936C/T and -634G/C Polymorphisms and Breast Cancer Susceptibility, Tumor Growth, and Metastases: Evidence From 20,728 Subjects

The relation between the polymorphisms of vascular endothelial growth factor (VEGF) and breast cancer remains inconclusive. In our meta-analysis based on 10,340 breast cancer patients and 10,388 controls, we found breast cancer susceptibility was elevated in individuals carrying the VEGF +936C allele, especially in Asians, and the +936CC increases tumor growth. The G allele of -634G/C polymorphism reduces breast cancer susceptibility in Asians, and breast cancer patients of -634GG genotype has decreased tumor growth. These results suggest that both the VEGF +936C/T and -634G/C polymorphisms influence breast cancer susceptibility and tumor growth, instead of metastasis.

A systematic review and meta-analysis of somatic and germline DNA sequence biomarkers of esophageal cancer survival, therapy response and stage

Recent advances in next generation sequencing reinforce the potential for DNA sequence markers to guide esophageal cancer management. We report the first systematic review and meta-analysis, identifying 94 markers of outcome and 41 of stage. Overall, evidence was poor. Meta-analyses demonstrated outcome associations for 6 tumor and 9 germline variants: priorities for prospective evaluation.

Introduction

There is an urgent need for biomarkers to help predict prognosis and guide management of esophageal cancer. This review identifies, evaluates and meta-analyses the evidence for reported somatic and germline DNA sequence biomarkers of outcome and stage.

Methods

A systematic review was carried out of the PubMed, EMBASE and Cochrane databases (20 August 2014), in conjunction with the ASCO Level of Evidence scale for biomarker research. Meta-analyses were carried out for all reported markers associated with outcome measures by more than one study.

Results

Four thousand and four articles were identified, 762 retrieved and 182 studies included. There were 65 reported markers of survival or recurrence 12 (18.5%) were excluded due to multiple comparisons. Following meta-analysis, significant associations were seen for six tumor variants (mutant TP53 and PIK3CA, copy number gain of ERBB2/HER2, CCND1 and FGF3, and chromosomal instability/ploidy) and seven germline polymorphisms: ERCC1 rs3212986, ERCC2 rs1799793, TP53 rs1042522, MDM2 rs2279744, TYMS rs34743033, ABCB1 rs1045642 and MTHFR rs1801133. Twelve germline markers of treatment complications were reported; 10 were excluded. Two tumor and 15 germline markers (11 excluded) of chemo (radio)therapy response were reported. Following meta-analysis, associations were demonstrated for mutant TP53, ERCC1 rs11615 and XRCC1 rs25487. There were 41 tumor/germline reported markers of stage; 27 (65.9%) were excluded.

Conclusions

Numerous DNA markers of outcome and stage have been reported, yet few are backed by high-quality evidence. Despite this, a small number of variants appear reliable. These merit evaluation in prospective trials, within the context of high-throughput sequencing and gene expression.

VEGF pathway polymorphisms as prognostic and pharmacogenetic factors in cancer: a 2013 update

With the recent advances in genomic medicine and the development of targeted antiangiogenic therapy for cancer patients, there has been an increased interest in the role of predictive and prognostic markers for antiangiogenic therapy. Here, we provide a summary of the angiogenesis pathway, the role of predictive and prognostic markers in cancer and a summary of the current literature and studies on predictive and prognostic markers for antiangiogenic therapy. Our aim is to summarize those studies that are currently in the literature with an emphasis on the future directions of the field from 2013 and beyond. We conclude by providing our perspective on the future directions of this growing field, as well as possible challenges and pitfalls along the way.

A systematic review of the predictive value of (18)FDG-PET in esophageal and esophagogastric junction cancer after neoadjuvant chemoradiation on the survival outcome stratification

PURPOSE

We studied the predictive value of [(18) F]fluorodeoxyglucose-positron emission tomography ((18)FDG-PET) for assessing disease-free (DFS) and overall survival (OS) in esophageal and esophagogastric junction cancer.

MATERIALS AND METHODS

A literature search (PUBMED/MEDLINE, EMBASE, Cochrane) was performed to identify full papers with (18)FDG-PET and survival data, using indexing terms and free text words. Studies with >10 patients with locally advanced esophageal cancer, presenting sequential or at least one post-adjuvant treatment (18)FDG-PET data and Kaplan-Meier survival curves with >6 months median follow-up period were included. We performed a meta-analysis for DFS and OS using the hazard ratio (HRs) as outcome measure. Sources of heterogeneity study were also explored.

RESULTS

We identified 26 eligible studies including a total of 1,544 patients (average age 62 years, 82% males). The TNM distribution was as follows: stage I 7%, II 24%, III 53% and IV 15%. The pooled HRs for complete metabolic response versus no response were 0.51 for OS (95% CI, 0.4-0.64; P < 0.00001) and 0.47 for DFS (95% CI, 0.38-0.57; P < 0.00001), respectively. No statistical heterogeneity was present. To explore sources of clinical heterogeneity, we also realised subgroup and regression analyses. Taken into account the moderate correlation between OS and DFS (ρ = 0.54), we used joint bivariate random regression model. These analyses did not show a statistically significant impact of study characteristics and PET modalities on the pooled outcome estimates.

CONCLUSION

Despite methodological and clinical heterogeneity, metabolic response on (18)FDG-PET is a significant predictor of long-term survival data.

Genotyping analysis and ¹⁸FDG uptake in breast cancer patients: a preliminary research

Background

Diagnostic imaging plays a relevant role in the care of patients with breast cancer (BC). Positron Emission Tomography (PET) with 18F-fluoro-2-deoxy-D-glucose (FDG) has been widely proven to be a clinical tool suitable for BC detection and staging in which the glucose analog supplies metabolic information about the tumor. A limited number of studies, sometimes controversial, describe possible associations between FDG uptake and single nucleotide polymorphisms (SNPs). For this reason this field has to be explored and clarified. We investigated the association of SNPs in GLUT1, HIF-1a, EPAS1, APEX1, VEGFA and MTHFR genes with the FDG uptake in BC.

Methods

In 26 caucasian individuals with primary BC, whole-body PET-CT scans were obtained and quantitative analysis was performed by calculating the maximum Standardized Uptake Value normalized to body-weight (SUVmax) and the mean SUV normalized to body-weight corrected for partial volume effect (SUVpvc). Human Gene Mutation Database and dbSNP Short Genetic Variations database were used to analyze gene regions containing the selected SNPs. Patient genotypes were obtained using Sanger DNA sequencing analysis performed by Capillary Electrophoresis.

Results

BC patients were genotyped for the following nine SNPs: GLUT1: rs841853 and rs710218; HIF-1a: rs11549465 and rs11549467; EPAS1: rs137853037 and rs137853036; APEX1: rs1130409; VEGFA: rs3025039 and MTHFR: rs1801133. In this work correlations between the nine potentially useful polymorphisms selected and previously suggested with tracer uptake (using both SUVmax and SUVpvc) were not found.

Conclusions

The possible functional influence of specific SNPs on FDG uptake needs further studies in human cancer. In summary, this is the first pilot study, to our knowledge, which investigates the association between a large panel of SNPs and FDG uptake specifically in BC patients. This work represents a multidisciplinary and translational medicine approach to study BC where, the possible correlation between SNPs and tracer uptake, may be considered to improve personalized cancer treatment and care.

Vascular endothelial growth factor pathway polymorphisms as prognostic and pharmacogenetic factors in cancer: a systematic review and meta-analysis

Angiogenesis is an important host process that interacts with cancer cells to promote growth, invasion, and metastasis. Numerous therapeutic agents targeting the VEGF pathway have been developed. Host variability in VEGF pathway can influence angiogenesis-dependent signaling, altering sensitivity to antiangiogenic drugs and prognosis. A systematic review and meta-analysis was conducted (May 1990-July 2011). Eligible studies involved cancer patients and compared polymorphisms in the VEGF pathway [VEGF and molecules directly interacting with VEGF: KDR, FLT1, FGF, FGF2, FGFR, NRP1, endostatin (encoded by COL18A1)], and reported one of the following outcomes: overall survival, progression-free survival, time to recurrence, disease-free survival, response rate, or drug toxicity. We identified 48 cancer studies assessing prognosis and 12 cancer studies exploring pharmacogenetics of anti-VEGF therapy across various VEGF pathway polymorphisms. There was marked inter- and intradisease site heterogeneity in the effect of polymorphisms on both outcome and response to therapy. Meta-analyses of 5 VEGF polymorphisms (+936C>T, -460T>C, +405G>C, -1154G>A, and -2578C>A) identified a significant prognostic relationship: VEGF +405G>C variants showed a highly statistically significant improvement in overall survival [HR, 0.74; 95% confidence interval, 0.60-0.91; P = 0.004]. Variants (heterozygotes and/or homozygotes) of VEGF +405G>C were significantly associated with improved survival in a meta-analysis of multiple cancer sites.

Gastric cancer: surgery in 2011

BACKGROUND

Treatment of gastric cancer is more and more becoming an individualized decision. The choice of the optimal approach is based on prognostic factors, on the anatomic site of the tumor, and on expectations about the response to neoadjuvant treatment. Early gastric cancer that is limited to the mucosal layer is the domain of endoscopic resections. As soon as the submucosal layer is invaded, surgical strategies with adequate lymphadenectomy become necessary.

DISCUSSION

In many East Asian Centers and some other centers in the world, these tumors are resected by a laparoscopic approach. With a high experience, this can be done with excellent quality and outcome. In locally advanced gastric cancer, multimodal treatment can improve survival in comparison to surgery alone. However, the strategies differ significantly around the world. While adjuvant chemoradiotherapy is standard in the USA, in Europe, perioperative chemotherapy is the first choice, and in Japan, adjuvant chemotherapy is recommended. In Europe, three randomized phase III studies on the value of preoperative chemotherapy have been performed. Two of them have shown that perioperative chemotherapy does significantly improve the survival of patients with adenocarcinoma of the stomach and of the esophagogastric junction. The one including only preoperative chemotherapy failed to show a survival benefit for the combined treatment arm but showed excellent outcomes in both the surgery alone and the preoperative chemotherapy arms. Based on these studies, patients with stage II or stage III disease are now treated with perioperative chemotherapy. Additionally, it is generally accepted for more than 10 years now that responding patients have a significantly improved prognosis compared to nonresponding patients. The percentage of responding patients varies depending on the applied regimen between 20% and 45%. Therefore, early response evaluation or response prediction is an utmost important field of research. Proximal tumors are treated with a transhiatal extended gastrectomy, tumors in the middle third with a total gastrectomy, and distal tumors with a subtotal gastrectomy, if possible. Modified D2 lymphadenectomy avoiding splenectomy is now accepted as the standard procedure, providing improved prognosis for certain subgroups of patients. Individualized resection and lymphadenectomy techniques for early tumor stages and response-based neoadjuvant concepts for locally advanced tumors are the challenge for the future.