Staining For VEGF-C Research Articles

Lymph Node Involvement in Early-Stage Cervical Cancer: Is Lymphangiogenesis a Risk Factor? Results from the MICROCOL Study.

Simple SummaryThe prognosis of cervical cancer is significantly influenced by lymph node involvement. The lymphatic system is the primary way of metastasis for cervical carcinoma, and lymph-vascular space invasion (LVSI) is considered the most important risk factor for pelvic lymph node metastasis (PLNM). Previous studies have not clarified the correlation between lymphangiogenesis and an increased risk of metastasis and tumor recurrence. The evaluation and identification of several markers of lymphangiogenesis may identify patients with high risk of PLNM. Our findings suggest that the lymphatic spread does not required the proliferation of new lymphatic endothelial cells. These results emphasize the importance of pre-existing peritumoral lymphatic vessels in the metastatic process in early cervical cancer.Background: In patients with cervical cancer, the presence of tumoral lymph-vascular space invasion (LVSI) is the main risk factor for pelvic lymph node metastasis (PLNM). The objective of this study was to evaluate the presence of several markers of lymphangiogenesis in early-stage cervical cancer and their correlation with PLNM and tumoral recurrence. Materials and Methods: Seventy-five patients with early-stage cervical carcinoma underwent sentinel lymph node (SLN) sampling in association with complete pelvic lymph node dissection. Primary tumors were stained with the following markers: Ki67, D2-40, CD31 and VEGF-C. A 3-year follow-up was performed to evaluate the disease-free survival. Results: Overall, 14 patients (18.6%) had PLNM. Positive LVSI was seen in 29 patients (38.6%). There was a significant correlation between LVSI evidenced by H/E staining and PLNM (p < 0.001). There was no correlation between high Ki67, CD31, D2-40, and VEGF-C staining with PLNM or tumor recurrence. Conclusions: Our data support that lymphatic spread does not require the proliferation of new lymphatic endothelial cells in early-stage cervical cancer. These results emphasize the importance of pre-existing peritumoral lymphatic vessels in the metastatic process in early cervical cancer. None of the markers of lymphangiogenesis and proliferation assessed in this study were predictive of PLNM or recurrence.

The immunohistochemical landscape of the VEGF family and its receptors in glioblastomas

BackgroundAngiogenesis is one of the hallmarks of cancer. This complex mechanism of tumor progression provides tumors cells with essential nutrients. There have been a limited number of investigations of markers of angiogenesis in Glioblastomas (GBMs), and most previous studies have focused on VEGF-A. Recent evidence suggests that there is a complex lymphatic system in central nervous system (CNS), which suggests VEGF-C and VEGF–D as interesting biomarker candidates. This study was designed to evaluate the expressions of VEGF-A, −C, −D and their co-receptors, VEGFR-1, VEGFR-2, and VEGFR-3 by immunohistochemistry (IHC) using a series of GBMs. In addition, we evaluate any putative correlations between IHC expression levels of VEGF and clinical data of patients.MethodsTumor samples of 70 GBM patients (64 isocitrate dehydrogenase-1 wildtype (wtIDH-1) and 6 mutant (mutIDH-1)) were assessed by IHC using tissue microarray platforms for VEGF subunits and their co-receptors. The medical records were reviewed for clinical and therapeutic data.ResultsAll VEGF subunits and receptors were highly expressed in GBMs: 57 out of 62 (91.9%), 53 out of 56 (94.6%) and 55 out of 63 cases (87.3%) showed VEGF-A, VEGF-C and -D imunoexpression, respectively. Interestingly, we had found both nuclear and cytoplasmic localization of VEGF-C staining in GBM tumor cells. The frequency of immunoexpression of VEGF receptors was the following: VEGFR-1, 65 out of 66 cases (98.5%); VEGFR-2, 63 out of 64 cases (98.4%); VEGFR-3, 49 out of 50 cases (90.0%). There were no significant differences in the patient overall survival (OS) related to the VEGF staining. A weak and monotonous correlation was observed between VEGF and its cognate receptors. The pattern of VEGF IHC was found to be similar when GBM mutIDH-1 subtypes were compared to wtIDH-1.ConclusionBoth VEGF-C and –D, together with their receptors, were found to be overexpressed in the majority GBMs, and the IHC expression levels did not correlate with OS or IDH status. To understand the significance of the interactions and increased expression of VEGF-C, VEGF-D, VEGFR-2, and VEGFR-3 axis in GBM requires more extensive studies. Also, functional assays using a larger series of GBM is also necessary to better address the biological meaning of nuclear VEGF-C expression in tumor cells.

P1.13-009 Macroscopic and Microscopic Lymphatic Remodeling Caused by VEGF-C Play a Key Role in Lymphatic Metastasis of Non-Small Cell Lung Cancer

Computed tomography (CT) lymphography by transbronchial injection of a water-soluble extracellular CT contrast agent was developed as a new method for identifying sentinel nodes (SNs) in patient with non-small cell lung cancer (NSCLC). SNs were identified in 87.8% of patients, and the accuracy rate of SN identification was 97.5%. CT lymphography images sometimes show enlargement of lymphatic vessel (Fig), and we noticed this finding is related to lymph node metastasis. Lymphatic vessel enlargement was seen in 80% of lymph node metastasis positive cases whereas only 24.2% of lymph node metastasis negative cases showed lymphatic vessel enlargement (p=0.027). The aim of this study was to investigate the relationship between the finding of lymphatic vessel enlargement seen in CT lymphography and tumor lymphangiogenesis including lymphatic vessel density or vascular endothelial growth factor (VEGF)-C. Lymphatic vessel enlargement was defined as a finding of an enhanced lymphatic vessel ≥ 3mm on CT lymphography. We examined formalin fixed paraffin embedded tumor samples of 36 patients who received CT lymphography preoperatively. Lymphatic vessel density was determined based on the number of peritumoral vessels immunoreactive to anti-D2-40 antibody. The percentage of tumor cells exhibiting cytoplasmic staining for VEGF-C was evaluated and ≥30% was defined as VEGF-C positive. Twelve out of 36 (33.3%) cases showed finding of the lymphatic vessel enlargement on CT lymphography. Peritumoral lymphatic vessel density of VEGF-C positive patients was significantly higher than that of VEGF-C negative patients (28.4 ± 11.6 vs 17.0 ± 10.5, p=0.005). Lymphatic vessel enlargement was more frequently seen in VEGF-C positive patients than in VEGF-C negative patients (53.8% vs 21.8% ± 10.5, p=0.056). Our study suggests VEGF-C secreted by tumor cells play a key role in the lymphatic remodeling and lymphatic vessel enlargement seen in CT lymphography may be a risk factor for lymph node metastasis of NSCLC.

Abstract 337: Kidney Injury Affects Metabolism and Modification of Apolipoprotein A1 Promoting Renal Lymphangiogenesis

Kidney disease causes ApoAI/HDL to lose their vasculoprotective effects. A likely mechanism for the protective loss is modification of ApoAI/HDL reactive carbonyls which are increased. Kidney injury increases reactive carbonyls and permits more ApoAI to escape into the glomerular ultrafiltrate. We examined how apoAI was metabolized in the injured proteinuric kidney. Nphs1-hCD25 mice (NEP25) expressing human CD25 in podocytes were injured by immunotoxin, LMB2. Six weeks after LMB2, we assessed urinary excretion and intrarenal localization of ApoAI and examined the renal lymphatic network with podoplanin. In vitro, we studied proximal tubular cells (PTC) and lymphatic endothelial cells (LEC) exposed to ApoAI or modified ApoAI (IsoLG-ApoAI). NEP25 mice developed glomerulosclerosis, increased urinary excretion of albumin and ApoAI with high molecular weight forms of ApoAI appearing in urine of injured mice assessed by western blot. Proteinuric kidneys had more ApoAI and VEGFC staining that localized to tubular epithelial cells and showed a dramatically more dense and complex lymphatic network than wild type mice. ApoAI localized to lymphatic vessels. Cultured PTC and LEC responded differently to normal and isolevuglandin (IsoLG)-modified ApoAI. In PTC, IsoLG-ApoAI promoted more ApoAI uptake and VEGFC secretion, a powerful lymphaniogenic stimulus. In LEC, IsoLG-ApoAI led to greater cell viability, migration and ROS production than normal ApoAI. Notably, supernatant of PTC exposed to ApoAI secreted a high molecular weight form of ApoAI. In conclusion, injury that disrupts the glomerular filtration barrier causing proteinuria also leads to a dramatic increase in filtered ApoAI followed by greater uptake by the proximal tubules, interstitium and lymphatic vessels. Proximal tubules can modify ApoAI and activate tubular secretion of VEGFC, which in turn promotes renal lymphangiogenesis and encourages delivery of kidney-modified ApoAI into circulation.

Immunohistochemical comparative analysis of lymphatic vessel density and VEGF-C expression in squamous cell carcinomas of the tongue between young and old patients

BackgroundSquamous cell carcinoma (SCC) of the oral cavity is a malignant epithelial tumor that most commonly involves the tongue, and mainly affects men between the fifth and seventh decades of life. This study compared the lymphatic vessel density and VEGF-C expression in SCCs of the tongue between young and old patients. MethodsThirty-four SCCs of the tongue, 17 diagnosed in young patients (≤40y) and 17 diagnosed in old patients (>50y), were evaluated by immunohistochemistry. Lymphatic microdensity was determined based on the number of vessels immunoreactive to anti-D2-40 antibody. The percentage of neoplastic cells exhibiting cytoplasmic staining for VEGF-C was established for each case. ResultsAssessment of intratumoral lymphatic microdensity (ILMD) disclosed a median number of 6.20 lymphatic vessels in young patients and of 6.60 in old patients (p=0.809). Analysis of peritumoral lymphatic microdensity (PLMD) revealed a median number of 3.60 lymphatic vessels in young patients and of 3.40 in old patients (p=0.769). In the tumor core, analysis of the percentage of immunopositive cells for VEGF-C revealed a median number of 95.95% in young patients and of 55.48% in old patients (p<0.001). In the deep invasive front, the median number of immunopositive cells for VEGF-C was 97.93% in young patients and 66.09% in old patients (p<0.001). ConclusionsThe results of this study suggest that the more aggressive biological behavior of SCC of the tongue in young patients may be related to a higher expression of VEGF-C.

1687 - VEGF and VEGF Receptors in Thymic Epithelial Tumors (Tet): Pathological Features and Clinical Implications

ABSTRACT Background Thymic Epithelial Tumors (TET) are very rare cancers. They derives from Thymic gland and are associated with different clinical syndromes, such as miastenic and Good syndrome and other immunological and paraneoplastic disorders. The principal treatment of these patients is chemotherapy with schedule containing cisplatin characterized by high response rates (60%). Unfortunately some patients do not respond at all and most patients do not achieve long-lasting remission. For these patients have not other therapeutic chances at the moment. There are few data of the efficacy of anti-angiogenetic drugs in TET but new knowledges are emerging on the potential use of this class of drugs in patients with TET on the basis of laboratory and preclinical translational findings. Materials and methods we investigated the expression of Vascular Endothelial Growth Factor (VEGF) and its receptors (VEGFR1, 2 and 3) in 200 TET arranged in Tissue Micro Array (TMA). We observed both histotype distribution and modulation of angiogenetic factors (both VEGFRs and VEGFs) in TET. Results we observed that, when compared with the low-grade counterpart, high grade TET (B2, B3 and Carcinomas) contained significantly higher numbers of VEGFA, VEGFC, VEGFD, VEGFR1 and VEGFR2 expressing tumor cells. In addition, in high grade TET, strong positive correlations between staining for VEGFA and those for all other markers were found. In the same tumors, VEGFC staining was not associated with VEGFR1, VEGFR3 and PDGFRB staining and no correlation was obtained between VEGFD and VEGFR1 or VEGFR3 staining. The co-expression in epithelial cells of growth factors and their receptors suggests the presence of autocrine mechanisms in TET. Conclusions according to our data VEGFs and VEGFRs in TET are potential targets of anti-angiogenesis drugs. Further studies are needed to investigate the potential role of anti-angiogenetic agents. Disclosure All authors have declared no conflicts of interest.

The effect of the expression of vascular endothelial growth factor (VEGF)-C and VEGF receptor-3 on the clinical outcome in patients with gastric carcinoma

Aims We aimed to investigate the relationship among VEGF-C/VEGFR-3 expression, lymphatic metastasis and patient prognosis in gastric carcinoma. Material and methods VEGF-C and VEGFR-3 expression in gastric carcinoma tissues obtained from 204 patients who underwent curative gastrectomy (105 cases presented with lymph node metastasis and 99 cases without metastasis) was examined immunohistochemically. There was no significant difference in the other clinicopathologic variables except for postoperative pathological tumor stage (pT) and TNM stage between the two groups. The results were statistically processed. Results The results showed that VEGF-C was located mainly in the cytoplasm of tumor cells and VEGFR-3 was found predominantly in the endothelium of lymphatic vessels. VEGF-C and VEGFR-3 expression was more frequent in gastric carcinoma tissues than that in normal gastric tissues, 54.90% and 35.29% respectively, which revealed that the expression of VEGF-C and VEGFR-3 was significantly stronger in patients with lymph node metastasis than in those without metastasis. Patients who had positive staining for VEGF-C showed significantly less favorable survival rates compared with patients who had negative staining for VEGF-C. The survival rates of patients who had positive staining for VEGFR-3 also were significantly lower compared with patients who had negative staining for VEGFR-3. Patients who had positive staining for both VEGF-C and VEGFR-3 exhibited the most unfavorable prognosis. Multivariate analysis demonstrated that the expression of VEGF-C and VEGFR-3 was an independent prognostic determinant. In addition, faint to moderate VEGF-C expression was detected in normal gastric epithelial cells (18/204, 8.9%). Conclusions VEGF-C and VEGFR-3 expression could serve as a prognostic biomarker in patients with gastric carcinoma.

An expression signature of syndecan-1 (CD138), E-cadherin and c-met is associated with factors of angiogenesis and lymphangiogenesis in ductal breast carcinoma in situ

IntroductionHeparan sulphate proteoglycan syndecan-1 modulates cell proliferation, adhesion, migration and angiogenesis. It is a coreceptor for the hepatocyte growth factor receptor c-met, and its coexpression with E-cadherin is synchronously regulated during epithelial-mesenchymal transition. In breast cancer, changes in the expression of syndecan-1, E-cadherin and c-met correlate with poor prognosis. In this study we evaluated whether coexpression of these functionally linked prognostic markers constitutes an expression signature in ductal carcinoma in situ (DCIS) of the breast that may promote cell proliferation and (lymph)angiogenesis.MethodsExpression of syndecan-1, E-cadherin and c-met was detected immunohistochemically using a tissue microarray in tumour specimens from 200 DCIS patients. Results were correlated with the expression patterns of angiogenic and lymphangiogenic markers. Coexpression of the three prognostic markers was evaluated in human breast cancer cells by confocal immunofluorescence microscopy and RT-PCR.ResultsCoexpression and membrane colocalization of the three markers was confirmed in MCF-7 cells. E-cadherin expression decreased, and c-met expression increased progressively in more aggressive cell lines. Tissue microarray analysis revealed strong positive staining of tumour cells for syndecan-1 in 72%, E-cadherin in 67.8% and c-met in 48.6% of DCIS. E-cadherin expression was significantly associated with c-met and syndecan-1. Expression of c-met and syndecan-1 was significantly more frequent in the subgroup of patients with pure DCIS than in those with DCIS and a coexisting invasive carcinoma. Levels of c-met and syndecan-1 expression were associated with HER2 expression. Expression of c-met significantly correlated with expression of endothelin A and B receptors, vascular endothelial growth factor (VEGF)-A and fibroblast growth factor receptor-1, whereas E-cadherin expression correlated significantly with endothelin A receptor, VEGF-A and VEGF-C staining.ConclusionSyndecan-1, E-cadherin and c-met constitute a marker signature associated with angiogenic and lymphangiogenic factors in DCIS. This coexpression may reflect a state of parallel activation of different signal transduction pathways, promoting tumour cell proliferation and angiogenesis. Our findings have implications for future therapeutic approaches in terms of a multiple target approach, which may be useful early in breast cancer progression.

Expression of VEGF-C, VEGF-D and their receptor VEGFR-3 in diffuse large B-cell lymphomas

Lymphangiogenesis—the new growth of lymphatic vessels is an important route for the metastatic spread of human cancer. The receptor tyrosine kinase VEGFR-3 is expressed predominantly on lymphatic endothelium, and activation by its ligands VEGF-C and VEGF-D induces lymhpangiogenesis. VEGF-C, VEGF-D and VEGFR-3 have been found to play an important role in the lymphangiogenesis of several cancers. The present study investigated the expression of these factors by immunohistochemical staining of diagnosis specimens from 38 patients with diffuse large B-cell lymphoma (DLBCL). VEGF-C, VEGF-D and VEGFR-3 were expressed in both lymphoma cells and endothelial cells of blood and lymphatic tissue in all but one patient (who was negative for VEGF-D in lymphoma). There was a significant correlation in the intensity of staining between VEGF-C and -D in lymphoma and blood vessels (P < 0.001), and between the intensity of staining of VEGF-D and the patient International Prognostic Index score (P = 0.049) and borderline significance with overall survival (P = 0.051). Mean microvessel count was 58 (range 23 – 120), and it increased in association with high-intensity VEGF-C staining in lymphoma cells. Our findings indicate the importance of lymphangiogenic factors in the pathogenesis of DLBCL and suggest a potential therapeutic role for antilymphangiogenesis agents.

The role of VEGF-C staining in predicting regional metastasis in melanoma

Boone, B.1; De Bacquer, D.2; Pauwels, C.1; Naeyaert, J.1; Brochez, L.1 Author Information

Expression of VEGF-C and Its Receptor VEGFR-3 in Diffuse Large B-Cell Lymphomas.

Vascular endothelial growth factor (VEGF)-C and its receptor tyrosine kinase VEGFR-3 are critical regulators of lymphangiogenesis. Their expression has been observed in a variety of solid tumors and was associated with lymph node metastasis in patients. The aim of this study was to evaluate whether aggressive lymphatic malignant cells express VEGF-C and its receptor VEGFR-3 and whether the expression correlates with intratumoral microvessel density, and patient outcome. Pathological specimens were taken at diagnosis from 29 diffuse large B-cell lymphoma (DLBCL) patients (11 men, 18 females, mean age 70 years) who were diagnosed between the years 1997–2001. The specimens were evaluated by immunohistochemical staining to determine the expression of VEGF-C and VEGFR-3 and the microvessel count (by factor-VIII-related antigen). All lymphoma specimens demonstrated positive staining for VEGF-C and VEGFR-3 with high intensity staining in 50% and 68% of the specimens respectively. The mean microvessel count was 58 (range 23–120) and blood vessels in all specimens demonstrating positive staining for both VEGF-C and VEGFR-3 (strong in 25% and 58% respectively). We found a significant correlation between high serum levels of β2 microglobulin and high VEGFR-3 staining. High intensity staining was found in 77% of the patients with high β2 microglobulin compared to 44% of the patients with normal β2 microglobulin level (p=0.03).The patients who expressed high intensity VEGFR-3 staining had worse survival. In the 13 patients who lived more than 5 years, only 46% of them demonstrated high intensity staining while 85% of patients that lived less than 5 years demonstrated such staining (p=0.01). The median event free survival (EFS) was 21 months. A significantly higher proportion of the patients with low EFS (lower than 21 months) demonstrated high intensity staining for VEGFR-3, (p=0.01)These results suggest that DLBCL tumors express both VEGF-C and its receptor (VEGFR-3) and that this signaling pathway may be associated with patient's prognosis. [Display omitted]

Expression of vascular endothelial growth factor receptor-3 by lymphatic endothelial cells is associated with lymph node metastasis in prostate cancer.

The molecular mechanisms underlying lymph node metastasis are poorly understood, despite the well-established clinical importance of lymph node status in many human cancers. Recently, vascular endothelial growth factor (VEGF)-C and VEGF-D have been implicated in the regulation of tumor lymphangiogenesis and enhancement of lymphatic invasion via activation of VEGF receptor-3. The purpose of this study was to determine the expression pattern of the VEGF-C/VEGF-D/VEGF receptor-3 axis in prostate cancer and its relationship with lymph node metastasis. The expression pattern of VEGF-C, VEGF-D, and VEGF receptor-3 in localized prostate cancer specimens (n = 37) was determined using immunohistochemistry. Widespread, heterogeneous staining for VEGF-C and VEGF-D was observed in all cancer specimens. Intensity of VEGF-C staining was lower in benign prostate epithelium than in adjacent carcinoma, whereas no difference between benign epithelium and carcinoma was observed for VEGF-D staining. VEGF receptor-3 immunostaining was detected in endothelial cells of lymphatic vessels in 18 of 37 tissue samples. The presence of VEGF receptor-3-positive vessels was associated with lymph node metastasis (P = 0.0002), Gleason grade (P < 0.0001), extracapsular extension (P = 0.0382), and surgical margin status (P = 0.0069). In addition, VEGF receptor-3 staining highlighted lymphatic invasion by VEGF-C-positive/VEGF-D-positive carcinoma cells. Together, these results suggest that paracrine activation of lymphatic endothelial cell VEGF receptor-3 by VEGF-C and/or VEGF-D may be involved in lymphatic metastasis. Thus the VEGF-C/VEGF-D/VEGF receptor-3 signaling pathway may provide a target for antilymphangiogenic therapy in prostate cancer.

Expression of vascular endothelial growth factor (VEGF)-C and VEGF-D, and their receptor VEGFR-3, during different stages of cervical carcinogenesis.

Cervical carcinogenesis has well-defined stages of disease progression including three grades of pre-invasive lesions--cervical intraepithelial neoplasia grades 1-3 (CIN 1-3)--and invasive cervical cancer. However, the biological properties of CIN lesions prone to develop invasive disease are not well defined. Recent observations suggest that early invasive disease spreads to regional lymph nodes in several tumour types and that growth factors (VEGF-C and VEGF-D) involved in new lymphatic vessel formation may play a crucial role in this process. The present study has assessed the expression of VEGF-C and VEGF-D, and their receptor VEGFR-3, in 152 cervical lesions (33 CIN 1, 33 CIN 2, 37 CIN 3, and 49 squamous cell carcinomas) to determine whether expression of lymphangiogenic factors occurs prior to invasion. The presence of lymphatic vessels was determined using LYVE-1 and podoplanin staining, as well as double immunostaining for LYVE-1/CD34 and podoplanin/CD34. In situ hybridization was performed to determine VEGFR-3 mRNA expression. A significant positive correlation was found between VEGF-C, VEGF-D, and VEGFR-3 expression through the different stages of cervical carcinogenesis. Significant differences in protein expression for VEGF-C, VEGF-D, and VEGFR-3 were found between CIN 1-2 and CIN 3 (p<0.001 for all), but not between CIN 3 and cervical cancer. More than 50% of the CIN 3 lesions showed moderate to strong staining for VEGF-C and VEGF-D, whereas most of the early pre-cancerous lesions (CIN 1 and 2) were negative. In cervical cancer, similar observations to those in CIN 3 were found. VEGFR-3 mRNA expression was found in the cytoplasm of epithelial neoplastic cells and VEGFR3 protein expression was found in more than 50% of CIN 3 lesions and cervical cancers, compared with 15% in CIN 1 and 2. These findings suggest an autocrine growth stimulation pattern via VEGFR-3. Adjacent CIN 3 was present in nine cervical cancers and displayed strong expression for VEGF-C, VEGF-D, and VEGFR-3. These results suggest that in cervical carcinogenesis a switch to the lymphangiogenic phenotype may occur at the stage of CIN 3.

Correlation between vascular endothelial growth factor-C expression and invasion phenotype in cervical carcinomas.

The correlation between vascular endothelial growth factor (VEGF)-C gene expression and in vitro invasive activity and matrix metalloproteinase (MMP)-2 or 9 gene expression and proteolytic activity in 11 cervical carcinoma cell lines, was investigated. Immunohistochemical expression of VEGF-C in 52 cervical carcinoma tissues was also correlated with tumor aggressiveness with respect to clinicopathologic features, tumor vascularity, MMP-2 expression and patient outcome. Expression of VEGF-C mRNA differed remarkably among the cell lines and there was a statistical correlation between VEGF-C gene expression and the number of invaded tumor cells (p = 0.0009) and MMP-2 gene expression and activity (p < 0.05). Anti-VEGF-C antibody inhibited the invasive and proteolytic activity of tumor cells in a concentration-dependent manner. VEGF-C or MMP-2 expression in clinical tissue samples was well correlated with depth of myometrial invasion, endometrial invasion, pelvic lymphnode metastasis and tumor vascularity (p < 0.05) and there was a close relation between VEGF-C and MMP-2 expression (p < 0.0001) in cervical carcinomas. Overall survival rates for 14 patients with strong VEGF-C staining tumors were lower than those for 38 patients with weak VEGF-C staining tumors (p = 0.0132) and VEGF-C tissue status emerged as an independent prognostic parameter (p = 0.0232). These results suggest that VEGF-C expression is closely related to invasion phenotype and affects the patient's survival in cervical carcinomas.

VEGF-C and VEGF-D expression in neuroendocrine cells and their receptor, VEGFR-3, in fenestrated blood vessels in human tissues.

Recently, vascular endothelial growth factor receptor 3 (VEGFR-3) has been shown to provide a specific marker for lymphatic endothelia in certain human tissues. In this study, we have investigated the expression of VEGFR-3 and its ligands VEGF-C and VEGF-D in fetal and adult tissues. VEGFR-3 was consistently detected in the endothelium of lymphatic vessels such as the thoracic duct, but fenestrated capillaries of several organs including the bone marrow, splenic and hepatic sinusoids, kidney glomeruli and endocrine glands also expressed this receptor. VEGF-C and VEGF-D, which bind both VEGFR-2 and VEGFR-3 were expressed in vascular smooth muscle cells. In addition, intense cytoplasmic staining for VEGF-C was observed in neuroendocrine cells such as the alpha cells of the islets of Langerhans, prolactin secreting cells of the anterior pituitary, adrenal medullary cells, and dispersed neuroendocrine cells of the gastrointestinal tract. VEGF-D was observed in the innermost zone of the adrenal cortex and in certain dispersed neuroendocrine cells. These results suggest that VEGF-C and VEGF-D have a paracrine function and perhaps a role in peptide release from secretory granules of certain neuroendocrine cells to surrounding capillaries.