Expression of vascular endothelial growth factor (VEGF) and its two receptors (VEGF-R1-Flt1 and VEGF-R2-Flk1/KDR) in non-small cell lung carcinomas (NSCLCs): correlation with angiogenesis and survival.

The formation of new vessels (angiogenesis) is essential for primary tumour growth and metastasis and is induced by several angiogenic factors, including vascular endothelial growth factor (VEGF). The microvascular density (MVD) in tumours was assessed and the expression of VEGF and its receptors VEGF-R1-Flt1 and VEGF-R2-KDR/Flk1 was investigated in the different cellular compartments in vivo, in order to establish their interrelationship and their prognostic influence. Immunohistochemical study of 69 stage I-II non-small cell lung carcinomas (NSCLCs) was performed on paraffin sections with CD34 antibody to estimate MVD, using a Chalkley eye-piece graticule and VEGF, VEGF-R1, and VEGF-R2 antibodies. There was strong expression of VEGF and its receptors in tumour cells, endothelial cells, and stromal fibroblasts. In tumour cells, the level of VEGF was correlated with that of VEGF-R1 ( p = 0. 018) but not that of VEGF-R2. In fibroblasts, high expression of VEGF was correlated with that of VEGF-R1 ( p = 0.0001) and VEGF-R2 ( p = 0.0001). In endothelial cells, expression of VEGF was correlated with that of VEGF-R1 ( p < 0.0001) and VEGF-R2 ( p = 0.04). The level of VEGF in fibroblasts was correlated with that of VEGF-R1 ( p = 0.0028) and VEGF-R2 ( p = 0.01) in endothelial cells. There was no correlation between the level of MVD and that of VEGF or VEGF-R1 or VEGF-R2. Neither the level of MVD, nor the level of expression of VEGF and VEGF receptors in any compartment influenced the patient's survival. In conclusion, although angiogenesis is essential for tumour growth, this study failed to demonstrate that MVD, VEGF, VEGF-R1, and VEGF-R2 are prognostic markers for stage I-II NSCLC. VEGF, however, might act as a direct autocrine growth factor for tumour cells via VEGF-R1 and angiogenesis could be promoted in a paracrine loop, where VEGF is produced by fibroblasts and tumour cells and then binds to endothelial cells via induced VEGF receptors. VEGF and its receptors thus appear as relevant therapeutic targets in NSCLC.

Decaussin M ，Sartelet H ，Robert C ，Moro D ，Claraz C ，Brambilla C ，Brambilla E ... -  《JOURNAL OF PATHOLOGY》

[Correlation of angiogenesis with expression of vascular endothelial growth factor and its receptors in lung carcinoma].

Zhang G ，Zhao M ，Xu M ，Yang Y ，Wang M ，Yang C ... -  《-》

Vascular endothelial growth factor/KDR activated microvessel density versus CD31 standard microvessel density in non-small cell lung cancer.

Koukourakis MI ，Giatromanolaki A ，Thorpe PE ，Brekken RA ，Sivridis E ，Kakolyris S ，Georgoulias V ，Gatter KC ，Harris AL ... -  《CANCER RESEARCH》

Relation of hypoxia inducible factor 1 alpha and 2 alpha in operable non-small cell lung cancer to angiogenic/molecular profile of tumours and survival.

Hypoxia inducible factors HIF1alpha and HIF2alpha are important proteins involved in the regulation of the transcription of a variety of genes related to erythropoiesis, glycolysis and angiogenesis. Hypoxic stimulation results in rapid increase of the HIF1alpha and 2alpha protein levels, as a consequence of a redox-sensitive stabilization. The HIFalphas enter the nucleus, heterodimerize with the HIF1beta protein, and bind to DNA at the hypoxia response elements (HREs) of target genes. In this study we evaluated the immunohistochemical expression of these proteins in 108 tissue samples from non-small-cell lung cancer (NSCLC) and in normal lung tissues. Both proteins showed a mixed cytoplasmic/nuclear pattern of expression in cancer cells, tumoural vessels and tumour-infiltrating macrophages, as well as in areas of metaplasia, while normal lung components showed negative or very weak cytoplasmic staining. Positive HIF1alpha and HIF2alpha expression was noted in 68/108 (62%) and in 54/108 (50%) of cases respectively. Correlation analysis of HIF2alpha expression with HIF1alpha expression showed a significant association (P< 0.0001, r = 0.44). A strong association of the expression of both proteins with the angiogenic factors VEGF (P< 0.004), PD-ECGF (P< 0.003) and bFGF (P< 0.04) was noted. HIF1alpha correlated with the expression of bek-bFGF receptor expression (P = 0.01), while HIF2alpha was associated with intense VEGF/KDR-activated vascularization (P = 0.002). HIF2alpha protein was less frequently expressed in cases with a medium microvessel density (MVD); a high rate of expression was noted in cases with both low and high MVD (P = 0.006). Analysis of overall survival showed that HIF2alpha expression was related to poor outcome (P = 0.008), even in the group of patients with low MVD (P = 0.009). HIF1alpha expression was marginally associated with poor prognosis (P = 0.08). In multivariate analysis HIF2alpha expression was an independent prognostic indicator (P = 0.006, t-ratio 2.7). We conclude that HIF1alpha and HIF2alpha overexpression is a common event in NSCLC, which is related to the up-regulation of various angiogenic factors and with poor prognosis. Targeting the HIF pathway may prove of importance in the treatment of NSCLC.

Giatromanolaki A ，Koukourakis MI ，Sivridis E ，Turley H ，Talks K ，Pezzella F ，Gatter KC ，Harris AL ... -  《-》

Vascular endothelial growth factor, platelet-derived endothelial cell growth factor and angiogenesis in non-small-cell lung cancer.

High microvessel density, an indirect measure of angiogenesis, has been shown to correlate with increased tumour size, lymph node involvement and poor prognosis in non-small-cell lung cancer (NSCLC). Tumour cell vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) expression correlate with angiogenesis and a poor outcome in this disease. In a retrospective study VEGF and PD-ECGF expression and microvessel density were evaluated immunohistochemically in surgically resected specimens (T1-3, N0-2) from 223 patients with operable NSCLC using the VG1, P-GF.44C and JC70 monoclonal antibodies respectively. High VEGF immunoreactivity was seen in 104 (46.6%) and PD-ECGF in 72 (32.3%) cases and both were associated with high vascular grade tumours (P= 0.009 and P= 0.05 respectively). Linear regression analysis revealed a weak positive correlation between VEGF and PD-ECGF expression in cancer cells (r= 0.21; P = 0.002). Co-expression of VEGF and PD-ECGF was not associated with a higher microvessel density than VEGF or PD-ECGF only expressing tumours. Furthermore a proportion of high vascular grade tumours expressed neither growth factor. Univariate analysis revealed tumour size, nodal status, microvessel density and VEGF and PD-ECGF expression as significant prognostic factors. Tumour size (P < 0.02) and microvessel density (P < 0.04) remained significant on multivariate analysis. In conclusion, VEGF and PD-ECGF are important angiogenic growth factors and have prognostic significance in NSCLC. Furthermore the study underlines the prognostic significance of microvessel density in operable NSCLC.

O'Byrne KJ ，Koukourakis MI ，Giatromanolaki A ，Cox G ，Turley H ，Steward WP ，Gatter K ，Harris AL ... -  《-》