Discrepancies between VEGF -1154 G>A polymorphism analysis performed in peripheral blood samples and FFPE tissue

Nonmalignant Formalin-Fixed Paraffin-Embedded Tissues as a Source to Study Germline Variants and Cancer Predisposition: A Systematic Review

Background: Archived formalin-fixed paraffin-embedded (FFPE) specimens from nonmalignant tissues derived from cancer patients are a vast and potentially valuable resource for high-quality genotyping analyses and could have a role in establishing inherited cancer risk. Methods: We systematically searched PubMed, Ovid MEDLINE, and Scopus databases for all articles that compared genotyping performance of DNA from nonmalignant FFPE tissue with blood DNA derived from cancer patients irrespective of tumor type. Two independent researchers screened the retrieved studies, removed duplicates, excluded irrelevant studies, and extracted genotyping data from the eligible studies. These studies included, but were not limited to, genotyping technique, reported call rate, and concordance. Results: Thirteen studies were reviewed, in which DNA from nonmalignant FFPE tissues derived from cancer patients was successfully purified and genotyped. All these studies used different approaches for genotyping of DNA from nonmalignant FFPE tissues to amplify single nucleotide polymorphisms (SNPs) and to estimate of loss of heterozygosity. The concordance between genotypes from nonmalignant FFPE tissues and blood derived from cancer patients was observed to be high, whereas the call rate of the tested SNPs was not reported in all included studies. Conclusion: This review illustrates that DNA from nonmalignant FFPE tissues derived from cancer patients can serve as an alternative and reliable source for assessment of germline DNA for various purposes, including assessment of cancer predisposition.

Multicenter prospective study of angiogenesis polymorphism validation in HCC patients treated with sorafenib. An INNOVATE study protocol

INTRODUCTION

Although sorafenib is the upfront standard of care for advanced hepatocellular carcinoma (HCC), molecular predictors of efficacy have not been identified yet. In the ALICE-1 study, rs2010963 of VEGF-A and VEGF-C proved to be independent predictive factors for progression-free survival (PFS) and overall survival (OS) in multivariate analysis. The ALICE-1 study results were confirmed in the ALICE-2 study, in which VEGF and VEGFR SNPs were analyzed. In the ePHAS study we analyzed the SNPs of eNOS. In univariate analysis, patients homozygous for an eNOS haplotype (HT1: T-4b at eNOS-786/eNOS VNTR) had significantly shorter median PFS and OS than those with other haplotypes. These data were confirmed in the validation set.

METHODS

This nonpharmacological, interventional, prospective multicenter study aims to determine whether eNOS, HIF-1, VEGF, Ang2 and VEGFR polymorphisms play a role in predicting the objective response rate, PFS, and OS of advanced HCC patients treated with sorafenib. The study will involve 160 advanced HCC patients with Child-Pugh class A disease. The primary aim is to validate the prognostic or predictive roles of eNOS, Ang2, HIF-1, VEGF and VEGFR polymorphisms in relation to the clinical outcome (PFS) of HCC patients treated with sorafenib.

CONCLUSIONS

Overall, our data may suggest that polymorphism analysis of the VEGF, VEGFR-2, HIF and eNOS genes can identify HCC patients who are more likely to benefit from sorafenib.

Angiogenesis genotyping in the selection of first-line treatment with either sunitinib or pazopanib for advanced renal cell carcinoma

Introduction

Recent data from the COMPARZ study seem to suggest a non-inferiority of pazopanib confronted with sunitinib in PFS and OS. We previously reported how VEGF and VEGFR polymorphisms might have a predictive role in patients treated with first-line sunitinib. Aim of our study was to investigate whether tumour angiogenesis genotyping could influence clinical outcome in RCC patients treated with either sunitinib or pazopanib, in order to help clinicians select the appropriate treatment for each patient.

Results

19 patients were treated with pazopanib while 78 received sunitinib. VEGF A rs833061 resulted significant in PFS in sunitinib vs pazopanib patients (CC+CT>TT in sunitinib, TT>CC+CT in pazopanib; p<0,0001); VEGF A rs2010963 resulted significant in PFS in sunitinib vs pazopanib patients (GG+CG>CC in sunitinib, CC>GG+CG in pazopanib; p<0,0001); VEGF A rs699947 resulted significant in PFS in sunitinib vs pazopanib patients (AA+AC>CC in sunitinib, CC>AA+AC in pazopanib; p<0,0001). OS showed no statistically significant difference.

Conclusions

in our analysis patients with opposite polymorphisms of rs833061, rs2010963, rs699947 of VEGF A seems to have a better PFS if treated with either sunitinib or pazopanib. Our data seem to suggest that biology could have a role choosing first line treatment for mRCC patients.

Methods

a retrospective analysis on 97 histologic samples of mRCC patients was conducted for VEGF-A, VEGF-C and VEGFR-1,2,3 single nucleotide polymorphisms (SNPs).

eNOS polymorphisms and clinical outcome in advanced HCC patients receiving sorafenib: final results of the ePHAS study

Sorafenib may reduce endothelial nitric oxide synthase (eNOS) activity by inhibiting vascular endothelial growth factor receptors (VEGF-R), leading to a decrease in nitric oxide production. In the Italian multicenter ePHAS (eNOS polymorphisms in HCC and sorafenib) study, we analyzed the role of eNOS polymorphisms in relation to clinical outcome in patients with hepatocellular carcinoma (HCC) receiving sorafenib. Our retrospective study included a training cohort of 41 HCC patients and a validation cohort of 87 HCC patients, all undergoing sorafenib treatment. Three eNOS polymorphisms (eNOS -786T>C, eNOS VNTR 27bp 4a/b and eNOS+894G>T) were analyzed by direct sequencing or Real Time PCR in relation to progression-free survival (PFS) and overall survival (OS) (log-rank test). In univariate analysis, training cohort patients homozygous for eNOS haplotype (HT1:T-4b at eNOS-786/eNOS VNTR) had a lower median PFS (2.6 vs. 5.8 months, P < 0.0001) and OS (3.2 vs.14.6 months, P = 0.024) than those with other haplotypes. In the validation set, patients homozygous for HT1 had a lower median PFS (2.0 vs. 6.7 months, P < 0.0001) and OS (6.4 vs.18.0 months, P < 0.0001) than those with other haplotypes. Multivariate analysis confirmed this haplotype as the only independent prognostic factor. Our results suggest that haplotype HT1 in the eNOS gene may be capable of identifying a subset of HCC patients who are resistant to sorafenib.

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.

CD44 single nucleotide polymorphism and isoform switching may predict gastric cancer recurrence

BACKGROUND AND OBJECTIVES

The clinical implications of single nucleotide polymorphisms (SNPs) in CD44 remain unclear. This study examined the relationships of CD44 SNPs with clinicopathological parameters and prognosis in Japanese gastric cancer patients.

METHODS

The CD44 SNPs were analyzed in 11 gastric cancer cell lines and 517 clinical specimens. The expression of CD44 standard (CD44s) and CD44 variant 9 isoform (CD44v9) transcripts were measured by quantitative real-time polymerase chain reaction.

RESULTS

The CD44 rs187116 A/A, A/G, and G/G genotypes were present in 10.3%, 45.1%, and 44.7% of patients, respectively. The presence of CD44 rs187116 A/G or G/G genotypes was significantly associated with positive peritoneal washing cytology (P = 0.012). Disease-free survival of patients with these genotypes was significantly worse than in those with the A/A genotype (P = 0.039). Multivariate analysis showed that the CD44 rs187116 was independently prognostic of disease-free survival (P = 0.047). The CD44s/CD44v9 ratio was significantly lower in patients with the CD44 rs187116 A/A genotype than in those with the A/G (P = 0.046) and G/G (P = 0.047) genotypes.

CONCLUSIONS

The CD44 rs187116 genotype could predict disease recurrence in Japanese gastric cancer patients, and the SNP was associated with CD44 isoform switching.

eNOS polymorphisms as predictors of efficacy of bevacizumab-based chemotherapy in metastatic colorectal cancer: data from a randomized clinical trial

BACKGROUND

Bevacizumab plus chemotherapy is a widely used therapeutic option for first-line treatment of metastatic colorectal cancer (mCRC). However, molecular predictors of bevacizumab efficacy have not yet been identified. We analyzed vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) polymorphisms in relation to response to bevacizumab.

METHODS

Two hundred and thirty-seven patients with mCRC enrolled onto the phase III prospective multicentre randomized "Italian Trial in Advanced Colorectal Cancer (ITACa)" trial were evaluated. One hundred fourteen patients received chemotherapy plus bevacizumab (CT + B) and 123 received chemotherapy (CT) alone. Five single nucleotide polymorphisms (SNPs) (-2578, -1498, -1154, -634 and +936) for VEGF and 2 SNPs (-786, +894) and one variable number tandem repeat in intron 4 for eNOS were analyzed for each patient. The polymorphisms were assessed in relation to progression-free survival (PFS), objective response rate (ORR) and overall survival (OS).

RESULTS

VEGF 936C/T, eNOS +894 G/T and VNTR were significantly correlated with outcome in CT + B patients, but not in CT-only patients. In particular, patients with a specific haplotype combination of the 2 eNOS polymorphisms (defined eNOS Haplo1/Haplo1 and eNOS Haplo 2/Haplo2) showed significantly longer PFS (15.0 vs 9.1 months, P = 0.001) and OS (34.5 vs 20.5 months P = 0.002), and a higher ORR (71 vs 45.9%, P = 0.013) than those with the other genotypes, respectively.

CONCLUSIONS

Specific eNOS polymorphisms may be capable of identifying a subset of mCRC patients who are more responsive to bevacizumab-based chemotherapy. If confirmed, these results would permit individually tailored treatment with bevacizumab.

Genotyping concordance in DNA extracted from formalin-fixed paraffin embedded (FFPE) breast tumor and whole blood for pharmacogenetic analyses

BACKGROUND

Cancer pharmacogenetic studies use archival tumor samples as a DNA source when germline DNA is unavailable. Genotyping DNA from formalin-fixed paraffin embedded tumors (FFPE-T) may be inaccurate due to FFPE storage, genetic aberrations, and/or insufficient DNA extraction. Our objective was to assess the extent and source of genotyping inaccuracy from FFPE-T DNA and demonstrate analytical validity of FFPE-T genotyping of candidate single nucleotide polymorphisms (SNPs) for pharmacogenetic analyses.

METHODS

Cancer pharmacogenetics SNPs were genotyped by Sequenom MassARRAYs in DNA harvested from matched FFPE-T, FFPE lymph node (FFPE-LN), and whole blood leukocyte samples obtained from breast cancer patients. No- and discordant-call rates were calculated for each tissue type and SNP. Analytical validity was defined as any SNP with <5% discordance between FFPE-T and blood and <10% discordance plus no-calls.

RESULTS

Matched samples from 114 patients were genotyped for 247 SNPs. No-call rate in FFPE-T was greater than FFPE-LN and blood (4.3% vs. 3.0% vs. 0.5%, p < 0.001). Discordant-call rate between FFPE-T and blood was very low, but greater than that between FFPE-LN and blood (1.1% vs. 0.3%, p < 0.001). Samples with heterozygous genotypes were more likely to be no- or discordantly-called in either tissue (p < 0.001). Analytical validity of FFPE-T genotyping was demonstrated for 218 (88%) SNPs.

CONCLUSIONS

No- and discordant-call rates were below concerning thresholds, confirming that most SNPs can be accurately genotyped from FFPE-T on our Sequenom platform. FFPE-T is a viable DNA source for prospective-retrospective pharmacogenetic analyses of clinical trial cohorts.