Vascular endothelial growth factor (VEGF) exerts its biological functions by its specific VEGF receptors (VEGFRs), which includes VEGFR-1, VEGFR-2, VEGFR-3, neuropilin-1 and neuropilin-2. These VEGF receptors not only distribute in endothelial cells, but also in epidermal keratinocytes. VEGFRs may play a significant role in pathogenesis of the epidermal neoplasm and the VEGF-VEGFR signaling pathway may be a novel therapy target for neoplasm derived from epidermis.
Animals ; Epidermis ; metabolism ; Humans ; Neoplasms ; metabolism ; Neuropilins ; genetics ; metabolism ; Receptors, Vascular Endothelial Growth Factor ; genetics ; metabolism ; Vascular Endothelial Growth Factor Receptor-1 ; genetics ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; genetics ; metabolism ; Vascular Endothelial Growth Factor Receptor-3 ; genetics ; metabolism

The study was to investigate the expression of VEGFA, VEGFC, angiopoietin-1, angiopoietin-2 and their receptors on yolk sac blood island, AGM region during gestation of 3th-12th weeks of human embryo. Human embryo contingently aborted at 3 - 12 weeks of gestation were collected with signed agreements of the pregnant women suffered from accidental abortions. The specimens were fixed by 4% paraformaldehyde and embedded by paraffin. 5 micro m serial sections were made. HE and immunohistochemistry method (SABC) and light-microscope were employed. The results showed that VEGFA and its receptors flt1/flk-1, VEGFC and its receptor flt-4, angiopoietin-2 and its receptor tie-2 proteins were expressed strongly and angiopoietin-1 was weakly expressed by hematopoietic cells and vascular endothelial cells of blood island at 21 and 25 days of gestation. In the 4th week of gestation, immuno-positive reaction of these factors and their receptors appeared in the aorta and mesonephros deposited in larger, rounded and nucleated cells which represented hematopoietic cells. Up to 7th week, positive hematopoietic cells in the regions were much abundant. The number of positive cells decreased at 8th week. Up to 12th week, almost all blood cells were immuno-negative. VEGFA, flt-1, flt-4, angiopoietin-1, angiopoietin-2 and Tie-2 protein were expressed mainly by gonad at 6 - 8 weeks, but it did not express VEGFC and flk-1. The immuno-reaction of the factors and their receptors could not detected in vascular endothelial cells during 3-12th weeks of gestation. It is concluded that hematopoietic cells and endothelial cells in blood island of yolk sac, mesonephros and dorsal aorta co-expressed some factors and their receptors in relation to vasculogenesis and hematopoiesis. Intraembryonic hematopoiesis began in the 4th week of gestation.
Angiopoietin-1 ; analysis ; Angiopoietin-2 ; analysis ; Embryo, Mammalian ; chemistry ; Extracellular Matrix Proteins ; analysis ; Humans ; Immunohistochemistry ; Receptor, TIE-2 ; analysis ; Receptors, Vascular Endothelial Growth Factor ; analysis ; Vascular Endothelial Growth Factor A ; analysis ; Vascular Endothelial Growth Factor C ; analysis ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-2 ; analysis ; Vascular Endothelial Growth Factor Receptor-3 ; analysis ; Yolk Sac ; chemistry

This study was to evaluate the expression of vascular endothelial growth factor receptors (VEGFRs) in tumor and stromal cells of tougue squamous cell carcinoma (SCC). We also wanted to characterize the differences, from the angiogenic aspect, between cancer-associated stromal cells and non-malignant stromal cells. Paraffin-embedded tumor specimens from eleven patients with tongue SCCs were studied. Immunohistochemical staining for VEGFR-1,-2, and -3 was performed on the tumor cells, stromal fibroblasts and tumor-associated macrophages of the specimens. The expression of all 3 receptors was detected in the tumor cells themselves of the biopsy specimens. All 3 receptors were also expressed on stromal cells, except that VEGFR-2 was not expressed in stromal fibroblasts. In radical excision specimens, the staining intensity for VEGFR-1, -2 in the tumor cells and VEGFR-1,-3 in the tumor-associated macrophages was significantly lower than that in the biopsy specimens (P < 0.05). By using the general marker of fibroblast and macrophage, 5B5 and CD68, respectively, we performed double immunofluorescence staining for 5B5 and each VEGFR in the stromal fibroblasts and for CD68 and each VEGFR in the tumor-associated macrophages of the radical excision specimens. We used 4 cases of fibroma and 4 cases of chronic inflammation tissue as the controls. It was found that only each marker was expressed in the control group, however, 5B5/VEGFR-1 and 5B5/VEGFR-3 in the stromal fibroblasts, and CD68/VEGFR-1 and CD68/VEGFR-3 in the tumor-associated macrophages were double stained in the radical excision specimens. Although our study used small number of specimens, the results of our study showed that in tongue SCC, in association with the angiogenesis, the stromal cells showed the activated phenotype and this was different from the nonmalignant stromal cells.
Biopsy ; Carcinoma, Squamous Cell* ; Fibroblasts ; Fibroma ; Fluorescent Antibody Technique ; Humans ; Inflammation ; Macrophages ; Phenotype ; Receptors, Vascular Endothelial Growth Factor* ; Stromal Cells* ; Tongue* ; Vascular Endothelial Growth Factor A* ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-2

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignant neoplasms and is a leading cause of mortality worldwide. Metastasis to the liver is a frequent event in patients with CRC. An essential step in the metastatic cascade is angiogenesis. METHODS: This study included 45 patients who underwent a partial colectomy with hepatic resection for CRC with hepatic metastases. Immunohistochemistry was performed using vascular endothelial growth factor (VEGF)-A, VEGF receptor (VEGFR)-1, VEGFR-2, and CD34 antibodies to examine the relationship between CRC with liver metastases and angiogenesis. RESULTS: CRC showed significantly stronger expression of VEGF-A, VEGFR-1, and VEGFR-2 than liver metastases (p < 0.05). Microvessel density was also higher in CRC than in liver metastases (p < 0.05). CONCLUSIONS: Compared with previous studies, we found a higher expression of VEGF-A, VEGFR-1, VEGFR-2, and microvessel density in CRC than in liver metastases, which could be ascribed to a difference in vessel distribution and blood supply in each organ. Given its profuse blood supply and distinct cell populations, the liver might provide a rich milieu for tumor cell growth with less expression of angiogenesis-inducing agents.
Antibodies ; Colectomy ; Colorectal Neoplasms ; Glycosaminoglycans ; Humans ; Immunohistochemistry ; Liver ; Microvessels ; Neoplasm Metastasis ; Receptors, Vascular Endothelial Growth Factor ; Thymus Gland ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-2 ; World Health Organization

OBJECTIVE: To Investigate the expression of vascular endothelial growth factor receptor-1, -2, and -3 (VEGFR-1, -2, and -3) mRNA in the eutopic and ectopic tissues in women with endometriosis. METHODS: At the time of laparoscopy or laparotomy for endometriosis, infertility or other benign gynecologic conditions, a biopsy specimen was taken from the endometrial cavity and a peritoneal endometriotic implant simultaneously whenever appropriate. For control samples, endometrial tissues were obtained from women without visual evidence of endomtriosis. We employed real time quantitative RT-PCR to quantify VEGFR gene expression of these tissues. Comparisions between each group were made using ANOVA (analysis of variance) and Kruskal-Wallis test and statistical significance was defined as p<0.05. RESULTS: The expression of VEGFR-1, -2, and, -3 mRNA was significantly higher in both eutopic and ectopic endometrial tissues of women with endometriosis than in control endometrial tissues during both proliferative and mid-secretory phase. In ectopic endometrial tissue, VEGFR-1 mRNA expression was significantly increased during the mid-secretory phase compared to the proliferative phase. There was a marked increase especially in VEGFR-3 mRNA expression in ectopic endometriotic lesions during the proliferative phase but its expression decreased during the mid-secretory phase. CONCLUSION: mRNA for VEGFR-1, -2, and -3 in an endometriotic lesions might be differentially expressed and their expression appears to be associated with the development of endometriosis.
Biopsy ; Choristoma ; Endometriosis* ; Female ; Gene Expression ; Humans ; Infertility ; Laparoscopy ; Laparotomy ; Receptors, Vascular Endothelial Growth Factor* ; RNA, Messenger ; Vascular Endothelial Growth Factor A* ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-3

OBJECTIVETo study the expression of vascular endothelial growth factor (VEGF) and its receptors, the fms-like tyrosine-1 (flt-1) and kinase insert domain-containing receptor (KDR) in endometrial carcinoma and investigate the functions of VEGF and its receptors for endometrial carcinoma angiogenesis and its relation to the grade of tumor.

METHODSImmunocytochemistry and in situ hybridization technique were used to measure the level of VEGF, flt-1, KDR protein and mRNA in endometrial carcinoma tissue from 23 patients and endometrial samples from 6 normal menopausal women. A few endometrial carcinoma samples were homogenized for Western blot analysis. The blood vessel density was estimated by counting blood vessels stained with endothelial marker VIII factor.

RESULTSThe VEGF and its receptors were widely expressed in the cytoplasm of endothelial cells and tumor cells of endometrial carcinoma. The level of VEGF protein in endothelial cells and endometrial cancer cells of grade II and III tumor tissues was higher than that in grade I and normal menopausal endometrium (P < 0.05). VEGF mRNA did not show higher expression with the increase of tumor grade but its expression in normal tissue was lower than that in cancer (P < 0.05). The expression of flt-1 protein and mRNA in endothelial cells got higher in III than in grade II and I (P < 0.05), but invariable in cancer cells (P > 0.05), flt-1 expression in cancer was higher than that in normal menopausal endometrium either in endothelial cells or in cancer cells (P < 0.05). The expression of KDR protein in endothelial and cancer cell was high but did not alter with the increase of tumor grade (P > 0.05), the level of its mRNA was higher in cancer than that in normal tissue (P < 0.05). The microvascular density in grade III (48 +/- 12) was higher than that in grade II (26 +/- 16), grade I (27 +/- 14) and normal menopausal tissue (26 +/- 11, P < 0.05).

CONCLUSIONSThe expression pattern of VEGF, flt-1 and KDR protein and mRNA increased with the increase of tumor grade in endometrial carcinoma indicates that VEGF and its receptors contribute to the neovascularization of tumors and is one of the factors that relate to rapid tumor growth of endometrial carcinoma.

Endometrial Neoplasms ; metabolism ; physiopathology ; Endothelial Growth Factors ; genetics ; metabolism ; Extracellular Matrix Proteins ; metabolism ; Female ; Gene Expression ; Humans ; Intercellular Signaling Peptides and Proteins ; genetics ; metabolism ; Lymphokines ; genetics ; metabolism ; Neovascularization, Pathologic ; RNA, Messenger ; metabolism ; Receptors, Vascular Endothelial Growth Factor ; genetics ; metabolism ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism ; Vascular Endothelial Growth Factors

OBJECTIVETo examine the expression of vascular endothelial growth factor (VEGF) and its receptors (VEGFR1, VEGFR2) in transdifferentiated human proximal tubular epithelial (HK-2) cell induced by transforming growth factor beta1 (TGFbeta1).

METHODSThe transdifferentiation of HK-2 cells was detected by evaluation of expression of alpha-SMA by cytoimmunochemistry and RT-PCR. The VEGF mRNA was evaluated with RT-PCR. The secreted VEGF in the culture media was measured with ELISA. The cellular VEGF, VEGFR1, and VEGFR2 were measured with Western blot.

RESULTSThe immunostain of alpha-SMA were positive in HK-2 cell induced by TGFbeta1 at the concentration of 5 and 8 ng/ml for 72 h. The expression of alpha-SMA mRNA was induced by TGFbeta1 in concentration- and time-dependent manners. The expressions of mRNA and protein of VEGF were upregulated by TGFbeta1 at the concentration of 0.1 and 1 ng/ml for 72 h and at the concentration of 8 ng/ml for 12 h and 24 h when compared with the control. But expressions of mRNA and protein of VEGF were downregulated by TGFbeta1 at the concentration of 3, 5, and 8 ng/ml for 72 h and at the concentration of 8 ng/ml for 36, 48, and 72 h, respectively. Meanwhile, Protein levels of VEGFR1 and VEGFR2 were upregulated by TGFbeta1 in concentration- and time- dependent manners.

CONCLUSIONSIncreased expression of VEGFR1 and VEGFR2 and two-phase change in VEGF expression occurred in the process of tubular epithelial transdifferentiation induced by TGFbeta1. Reduced expression of VEGF may contribute to tubular epithelial transdifferentiation in a vicious circle.

Cell Differentiation ; Epithelial Cells ; cytology ; Humans ; Kidney Tubules, Proximal ; cytology ; RNA, Messenger ; metabolism ; Receptors, Vascular Endothelial Growth Factor ; metabolism ; Transforming Growth Factor beta ; pharmacology ; Transforming Growth Factor beta1 ; Vascular Endothelial Growth Factor A ; metabolism ; Vascular Endothelial Growth Factor Receptor-1 ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

PURPOSE: To investigate the effects of anti-vascular endothelial growth factor (VEGF) antibody on the survival of retinal ganglion cell (RGC)-5 cells differentiated with staurosporine under oxidative stress. METHODS: We used real-time polymerase chain reaction and Western blot to confirm the expression of VEGF, VEGF receptor (VEGFR)-1 and VEGFR-2 in RGC-5 cells differentiated with staurosporine for 6 hours. The differentiated RGC-5 cells were treated with 800 µM hydrogen peroxide (H₂O₂) for 24 hours to induce oxidative stress. Then, the survival rate of RGC-5 was confirmed by lactate dehydrogenase assay at each concentration (0, 0.01, 0.1, and 1 mg) using bevacizumab as the anti-VEGF antibody. The expression of VEGF, VEGFR-1, and VEGFR-2 was confirmed using real-time polymerase chain reaction. RESULTS: VEGF, VEGFR-1, and VEGFR-2 were all expressed in differentiated RGC-5 cells. When RGC-5 cells were simultaneously treated with bevacizumab and 800 µM H₂O₂, survival of RGC-5 decreased with bevacizumab concentration. VEGF expression in RGC-5 cells increased with increasing concentration of bevacizumab. Similar patterns were observed for VEGFR-1 and VEGFR-2, but the degree of increase was smaller than that for VEGF. CONCLUSIONS: When bevacizumab was administered to differentiated RGC-5 cells, the cell damage caused by oxidative stress increased. Therefore, given these in vitro study results, caution should be exercised with bevacizumab treatment.
Bevacizumab ; Blotting, Western ; Endothelial Growth Factors* ; Hydrogen Peroxide ; In Vitro Techniques ; L-Lactate Dehydrogenase ; Oxidative Stress ; Real-Time Polymerase Chain Reaction ; Receptors, Vascular Endothelial Growth Factor ; Retinal Ganglion Cells* ; Retinaldehyde* ; Staurosporine ; Survival Rate ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-2

Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) have been thought to be primarily involved in promoting angiogenesis. It is well known that VEGF and its receptors have been reported to play an important role in the regulation of the interaction between angiogenesis and osteogenesis during bone repair processes. Dexamethasone, a potent synthetic glucocorticoid, promotes phenotype markers of osteoblast differentiation, such as ALP and osteocalcin. It stimulates in vitro osteogenesis of human bone marrow osteogenic stromal cells. Dexamethasone has been reported to suppress VEGF gene expression in some cells. However, our previous study demonstrated VEGF quantification increased in a time-dependent manner in periosteal-derived osteogenesis under dexamethasone. So, the purpose of this study was to examine the angiogenic phenotypes in cultured human periostealderived cells under high-dose dexamethasone. Periosteal-derived cells were cultured using a technique previously described. After passage 3, the periosteal-derived cells were further cultured for 28 days in an osteogenic inductive culture medium containing ascorbic acid, beta-glycerophosphate and high-dose dexamethasone, We evaluated the expression of VEGF isoforms, VEGFR-1, VEGFR-2, and neuropilin-1. ALL VEGF isoforms (VEGF(121), VEGF(165), VEGF(189), and VEGF(206)) expression was observed by RT-PCR analysis. VEGFR-1, VEGFR-2 and neuropilin-1 expression increased up to day 14, particularly during the early stage of mineralization. Our results suggest the involvement of direct VEGFs/VEGFRs system on periosteal-derived cells during early mineralization phase under high-dose of dexamethasone. These also suggest that VEGF might act as an autocrine growth molecule during osteoblastic differentiation of cultured human periosteal-derived cells.]]>
Ascorbic Acid ; Bone Development ; Bone Marrow ; Dexamethasone ; Durapatite ; Fractures, Bone ; Gene Expression ; Glycerophosphates ; Humans ; Neuropilin-1 ; Osteoblasts ; Osteocalcin ; Osteogenesis ; Phenotype ; Protein Isoforms ; Receptors, Vascular Endothelial Growth Factor ; Stromal Cells ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factor Receptor-1 ; Vascular Endothelial Growth Factor Receptor-2

vascular origin, which are main causes of treatment failure. The reasons for the affinity for vascular metastatic potential are unclear. Therefore, molecular characteristics that influence the dissemination of metastatic tumor cells are important for the design of more effective treatment of salivary ACC. Tumor angiogenesis has been known to be essential for the distant metastasis of malignant cells. So, we determined expressions of vascular metastasis related factors in orthotopic (parotid) murine models of parotid ACC and compared with those in ectopic (subcutis) tumors of athymic mice.EXPERIMENTAL DESIGN: Using specimens from murine parotid (orthotopic, experimental group) and subcutaneous (ectopic, control group) tumors, which have developed via transplantation of tumor cells, originated from human parotid ACC, we performed immunohistochemical assays with anti-vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF, FGF2), matrix metalloproteinase (MMP)-9, and interleukin (IL)-8 antibodies. We also performed immunohistochemical assays with VEGF receptor (VEGFR)-1, VEGFR-2, VEGFR-3, and phosphorylated VEGFR-2.RESULTS: Transplantation of human ACC tumor cell (5x10(5)) into the parotid and subcutis successfully resulted in orthotopic (parotid) and ectopic (subcutaneous) tumors in athymic mice. Immunohistochemical staining demonstrated higher expression of major angiogenic factors (VEGF, bFGF, MMP-9) in the orthotopic tumors than in ectopic tumors (P < 0.05). But the expression level of angiogenic receptors were same in orthotopic and ectopic tumors of parotid ACC.CONCLUSION: VEGF, bFGF, and MMP-9 could be a good candidates for antiangiogenic therapy for the contol of vascular metastatic lesions of salivary ACC.]]>
Angiogenesis Inducing Agents ; Animals ; Antibodies ; Carcinoma, Adenoid Cystic ; Endothelial Growth Factors ; Fibroblast Growth Factor 2 ; Humans ; Interleukins ; Mice ; Mice, Nude ; Neoplasm Metastasis ; Receptors, Vascular Endothelial Growth Factor ; Research Design ; Salivary Glands ; Treatment Failure ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factor Receptor-2 ; Vascular Endothelial Growth Factor Receptor-3