Circulating serum levels of angiogenic factors and vascular endothelial growth factor receptors 1 and 2 in melanoma patients

Angiogenesis is essential for tumor progression and metastasis; however, the angiogenesis regulators that are biologically relevant for melanoma are still unknown. In this study, we analyzed the circulating serum levels of potent angiogenic factors, including vascular endothelial growth factor (VEGF), angiogenin, transforming growth factor-beta 1 and VEGF receptors, VEGFR1 and VEGFR2, in human melanoma patients. One hundred and fourteen patients with histopathologically verified cutaneous melanoma at different stages and 30 healthy controls were investigated. Serum levels of angiogenic factors and VEGF receptors were quantitatively analyzed by solid-phase enzyme-linked immunosorbent assay. The age of the patients (61 men and 53 women) ranged from 18 to 80 years; median age was 51 years. Serum transforming growth factor-beta 1 (P < 0.001), VEGF (P=0.006) and VEGFR1 (P=0.007) levels were significantly higher in patients with melanoma than in the control group. No significant differences, however, exist in the serum angiogenin and VEGFR2 levels between melanoma patients and the controls. The positive correlations of elevated serum levels of transforming growth factor-beta 1, VEGF and VEGFR1 with advanced stages of disease were found. Significant relationship was found only between serum levels of VEGF and VEGFR2. Elevated serum transforming growth factor-beta 1 (P < 0.001) and VEGF levels (P=0.0012) were found to be poor prognostic factors. Serum level of angiogenin and VEGF receptors, however, had no effect on survival. Our data suggest that the angiogenic serum factors, including VEGF, transforming growth factor-beta 1 and VEGFR1, but not angiogenin and VEGFR2 were increased in melanoma patients, especially associated with advanced disease stages. The mechanism of VEGF regulation of angiogenesis may in part be due to enhanced proliferation of VEGFRs, especially VEGFR1

Serum vascular endothelial growth factor (VEGF) and Bcl-2 levels in advanced stage non-small cell lung cancer

The characteristic changes in cancer process are assumed to be genetic alterations about the imbalance of cell proliferation and apoptotic cell death. This study was conducted to determine the value of the circulating vascular endothelial growth factor (VEGF) and Bcl-2 in patients with advanced stage non-small cell lung cancer (NSCLC). These serum factors were measured of 52 NSCLC patients pathologically verified on before and after chemotherapy in comparison with 16 healthy controls by using ELISA method. Both of the serum levels of VEGF (p = 0.015) and Bcl-2 (p < 0.001) were increased significantly in NSCLC patients compared with the healthy controls. No statistically significant relationships between investigated elevated serum parameters and various characteristics of patients and disease such as stage and tumor burden were determined. Likewise, we also found no correlation between serum VEGF and Bcl-2. Cytotoxic therapy of patients was accompanied by unchanged serum levels of serum factors. The median survival of all patients was 27 weeks and one-year survival rate was 22.4 percent. With the median serum levels as the cut-off value, patients were divided into high- and low-serum parameter groups. While we found that patients' performance status (p < 0.0001), serum LDH level (p = 0.0002), response to chemotherapy (p = 0.0023), and stage of the disease (p = 0.0085) were prognostic factors for survival, serum VEGF (p = 0.48) and Bcl-2 (p = 0.91) levels were determined as ineffective on survival in patients with advanced NSCLC. In conclusion, our data suggest that these serum factors, VEGF and Bcl-2, are useful diagnostic factors, not predictive and prognostic markers for overall survival in advanced NSCLC patients