Serum and plasma vascular endothelial growth factor levels in testicular cancer patients

Is vascular endothelial growth factor a useful biomarker in giant cell arteritis?

Objectives

To assess the performance of circulating vascular endothelial growth factor (VEGF) levels as a tool for diagnosing giant cell arteritis (GCA) in a cohort of patients referred for assessment of suspected GCA.

Methods

We selected 298 patients recruited to the multicentre study Temporal Artery Biopsy versus Ultrasound in diagnosis of suspected GCA (TABUL). In a random subset of 26 biopsy-proven GCA cases and 26 controls, serum from weeks 0, 2 and 26 was analysed for VEGF concentration using ELISA. VEGF concentration at week 0 was used to generate a receiver-operating characteristic curve and thereby identify a cut-off for an abnormal result which was used to analyse the full patient cohort. Sections of paraffin-embedded temporal artery were stained by immunohistochemistry for VEGF.

Results

The mean (95% CI) VEGF concentration at week 0 was 873 pg/mL (631 to 1110) in 26 patients versus 476 pg/mL (328 to 625) in 26 controls (p=0.017). This difference was not observed at any other time point. The optimal cut-off of 713 pg/mL was applied to the whole patient cohort (n=298), yielding sensitivity of 32% and specificity of 85%. This was not improved by combination with any clinical parameters. When patients with biopsy-proven GCA were compared with controls, sensitivity was 58% and specificity remained 85%. Sections of biopsy from biopsy-positive GCA showed intense staining in the adventitia which was not seen in controls.

Conclusions

Serum VEGF concentration predicts biopsy positivity but is not useful for differentiating clinical cases of GCA from controls. Further studies into VEGF as a prognostic marker and therapeutic target are warranted.

Trial registration number

NCT00974883; Post-results.

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.

Vascular endothelial growth factor levels in serum and plasma from patients undergoing controlled ovarian hyperstimulation for IVF

BACKGROUND

Vascular endothelial growth factor (VEGF) has been investigated as a marker of ovarian response to controlled ovarian hyperstimulation and as a predictor of ovarian hyperstimulation syndrome (OHSS) in IVF cycles. In most studies, serum has been used for circulating VEGF concentration measurement, but it has been suggested that plasma is the preferred medium to measure VEGF levels because of the potential contribution of VEGF released from platelets during blood clotting. This study investigated VEGF concentrations in paired serum and plasma samples from patients undergoing controlled ovarian hyperstimulation for IVF.

METHODS

Serum and plasma VEGF levels, as well as the number of platelets, were measured in 30 IVF patients who comprised three study groups delineated according to the estradiol (E(2)) serum concentration reached on the day of HCG administration: 10 patients having low E(2) serum levels (<1500 pg/ml, group L), 10 patients having intermediate E(2) serum levels (1500-3000 pg/ml, group I) and 10 patients having high E(2) serum levels (>3000 pg/ml, group H).

RESULTS

There was a statistically significant correlation between plasma and serum VEGF levels (rho = 0.61; P < 0.005) for the entire population studied, although serum values were higher by a factor of approximately 6-fold. No significant correlation was found between peripheral blood VEGF concentrations and serum E(2) or follicle number on HCG day or the number of oocytes collected. Similarly, paired serum and plasma VEGF measurements did not correlate with platelet count.

CONCLUSIONS

Serum and plasma VEGF concentrations are strongly correlated in paired samples from infertile patients undergoing controlled ovarian hyperstimulation. However, neither serum nor plasma VEGF levels were correlated with parameters associated with ovarian follicular activity. Peripheral blood VEGF levels were not correlated with platelet count.