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Endothelial Growth Factor Expression (endothelial + growth_factor_expression)
Kinds of Endothelial Growth Factor Expression Selected AbstractsInduction of vascular endothelial growth factor expression in human pulp fibroblasts stimulated with black-pigmented BacteroidesINTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2004L.-C. Yang Abstract Aim, To investigate the effect of black-pigmented Bacteroides on the expression of vascular endothelial growth factor (VEGF) gene in human pulp fibroblasts. Methodology, The supernatants of Porphyromonas endodontalis, Porphyromonas gingivalis and Prevotella intermedia were used to evaluate VEGF gene expression in human pulp fibroblasts. The levels of mRNAs were measured by the quantitative reverse-transcriptase polymerase chain reaction analysis. Results, Black-pigmented Bacteroides induced significantly high levels of VEGF mRNA gene expression in human pulp fibroblasts (P < 0.05). In addition, the expression of VEGF depended on the bacteria tested. Conclusions, Black-pigmented Bacteroides may be involved in developing pulpal disease through the stimulation of VEGF production that would lead to the expansion of the vascular network coincident to progression of the inflammation. [source] Tenascin-C regulates angiogenesis in tumor through the regulation of vascular endothelial growth factor expressionINTERNATIONAL JOURNAL OF CANCER, Issue 1 2004Keiichiro Tanaka Abstract In order to verify whether tenascin-C (TN-C) is involved in angiogenesis as an extracellular signal molecule during tumorigenesis, cancerous cell transplantation experiments and coculture experiments were carried out, focusing on the regulation of vascular endothelial growth factor (VEGF). The A375 human melanoma cells introduced the GFP gene (A375-GFP), implanted subcutaneously into BALB/cA nude (WT) and TN-C knockout BALB/cA nude (TNKO) congenic mice. Furthermore, coculture experiments between A375-GFP and embryonic mesenchyme, which was prepared from both genotypes, were carried out to investigate the molecular mechanism in the cell-cell interactions. Both the content of TN-C and that of VEGF in the tumor and the conditioned medium were analyzed by the sandwich ELISA method. Seven days after transplantation of the A375-GFP, capillary nets became far more abundant in the tumors grown in WT mice than those in TNKO mice. Interestingly, VEGF and TN-C expressions showed antithetical expression patterns between the tumors in WT mice and those in TNKO mice. This peculiar phenomenon seems to be caused by a time lag prior to the onset of the mesenchymal regulation for the TN-C expression of A375-GFP. The coculture experiments revealed that WT mesenchyme had a much stronger effect than TNKO mesenchyme on both TN-C and VEGF expression. However, the defects of TNKO mesenchyme were restored in all cases by additional TN-C. These results clearly indicated that the expressions of both TN-C and VEGF depend on the surrounding mesenchyme, and that the function of mesenchyme is regulated by its own mesenchymal TN-C. In conclusion, the present data suggest that the matrix microenvironment organized by the host mesenchyme is very important for angiogenesis in tumor development. © 2003 Wiley-Liss, Inc. [source] Overexpression of c-H-ras p21 is correlated with vascular endothelial growth factor expression and neovascularization in advanced gastric carcinoma ,JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2000Young-Bae Kim Abstract Background and Aims ras Gene and its product (p21) have been reported to be associated with vascular endothelial growth factor (VEGF), which is one of the most important angiogenic factors, and tumor-associated angiogenesis. We tried to evaluate the correlation between the expression of c-H-ras gene product p21 and angiogenesis in advanced gastric carcinoma. Methods Immunohistochemical expression of c-H-ras p21 and VEGF was examined in 49 advanced gastric adenocarcinomas. In addition, double immunohistochemical staining was performed using anti-CD34 and anti-Ki-67 antibodies, and the intratumoral microvessel densities and their endothelial proliferative labeling indices were then counted to evaluate the degree of angiogenesis. Results The expression of c-H-ras p21 was demonstrated in 43 out of 49 gastric adenocarcinomas (87.8%). It did not correlate with histologic type, depth of invasion or metastasis. However, the degree of c-H-ras p21 expression was correlated with VEGF. In addition, the degree of c-H-ras p21 expression was correlated with increased intratumoral microvascular density and endothelial proliferative activity. Conclusions We suggest that c-H-ras oncogene product p21 contributes to the upregulation of tumor-associated angiogenesis by the increased production of VEGF in advanced gastric carcinomas. Therefore, treatment involving the targeting of ras oncogene could inhibit solid tumor growth by suppressing tumor-associated angiogenesis. [source] Cyclic GMP phosphodiesterase inhibition alters the glial inflammatory response, reduces oxidative stress and cell death and increases angiogenesis following focal brain injuryJOURNAL OF NEUROCHEMISTRY, Issue 3 2010Paula Pifarré J. Neurochem. (2010) 112, 807,817. Abstract Recent evidence obtained in cultured glial cells indicates that cGMP-mediated pathways regulate cytoskeleton dynamics, glial fibrillary acidic protein expression and motility in astrocytes, as well as inflammatory gene expression in microglia, suggesting a role in the regulation of the glial reactive phenotype. The aim of this work was to examine if cGMP regulates the glial inflammatory response in vivo following CNS damage caused by a focal cryolesion onto the cortex in rats. Results show that treatment with the cGMP phosphodiesterase inhibitor zaprinast (10 mg/kg i.p.) 2 h before and 24 and 48 h after the lesion results 3 days post-lesion in notably enhanced astrogliosis manifested by increased glial fibrillary acidic protein immunoreactivity and protein levels around the lesion. In contrast, zaprinast decreased the number of round/ameboid lectin-positive cells and the expression of the activated microglia/macrophage markers Iba-1 and CD11b indicating decreased recruitment and activation of these cells. This altered inflammatory response is accompanied by a decrease in protein oxidative stress, apoptotic cell death and neuronal degeneration. In addition, zaprinast enhanced angiogenesis in the lesioned cortex probably as a result of vascular endothelial growth factor expression in reactive astrocytes. These results suggest that regulation of the glial inflammatory response may contribute to the reported neuroprotective effects of cGMP-phosphodiesterase inhibitors in brain injury. [source] Effect of ketoprofen in topical formulation on vascular endothelial growth factor expression and tumor growth in nude mice with osteosarcomaJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2004Kenshi Sakayama Abstract OST cells, a low metastatic cell line established from human osteosarcoma, were inoculated under the periosteum of the ossa cranii of nude mice. Four weeks later, tumors were percutaneously treated for an additional 4 weeks with a patch containing either placebo or ketoprofen (KP). In the placebo group, OST cells formed osteoid and invaded the cranial bone. Tumor mass weighed 3.54 g. Approximately 85% of cells within the tumor expressed proliferating cell nuclear antigen (PCNA), indicating that they were proliferating with a high mitotic activity. Many feeder vessels were located within the tumor. The majority of tumor cells expressed intensely vascular endothelial growth factor (VEGF). In the KP group, invasion of OST cells into the cranial bone was suppressed and the tumor mass was 47% of that of the placebo group. Approximately 65% of cells within the tumor were PCNA-negative, indicating that their growth was arrested. There were considerably fewer feeder vessels within the tumor in the KP group than in the placebo group. Only a small number of cells expressed VEGF. Based on these findings, we concluded that topical administration of KP to nude mice with osteosarcoma inhibited VEGF expression, reduced the development of feeder vessels for supply of nutrients and oxygen, and suppressed tumor growth. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Expression of cyclooxygenase-2 in primary and remnant gastric carcinoma: Comparing it with p53 accumulation, Helicobacter pylori infection, and vascular endothelial growth factor expressionJOURNAL OF SURGICAL ONCOLOGY, Issue 2 2002Atsushi Kawabe MD Abstract Background and Objectives Cyclooxygenase-2 (COX-2) expression may contribute to the synthesis of prostanoids, which have been related to carcinogenesis and tumor progression. It is well known that the gastric remnant is at greater risk of the development of gastric cancer than is the whole stomach; incidence rates for gastric cardia adenocarcinoma are rising in the United States and Europe. Our objective was to determine the involvement of COX-2 in primary and remnant gastric cancer tissues as well as in adjacent noncancerous mucosa. Methods We investigated the expression of COX-2 in 91 human gastric cancer tissue and adjacent noncancerous mucosa samples (40 remnant gastric cancer, 37 gastric cardia cancer, and 14 gastric corpus and antrum cancer), using immunohistochemistry. In addition, p53 expression, Helicobacter pylori infection, and vascular endothelial growth factor in the tissues were evaluated by immunohistochemical staining and compared with COX-2 expression. Results There were no significant differences in clinicopathological data in the gastric cancer tissues. There was a significant relation between the expression of COX-2 and p53 in gastric cancer tissues (P,=,0.0048). However, vascular endothelial growth factor expression and Helicobacter pylori infection showed no correlation with the expression of COX-2. In the case of adjacent noncancerous mucosa, the positive rate of COX-2 expression was significantly higher in the remnant gastric cancers (75.0%) than in the primary gastric cancers (25.5%) (P,<,0.0001). Conclusions This information may help in the analysis of the carcinogenesis of gastric cancer; there is also a possibility that the COX-2 selective inhibitor to the remnant gastric cancer has a chemopreventive effect. J. Surg. Oncol. 2002;80:79,88. © 2002 Wiley-Liss, Inc. [source] Age-dependent vascular endothelial growth factor expression and angiogenic capability of bladder smooth muscle cells: implications for cell-seeded technology in bladder tissue engineeringJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 8 2009Joseph Azzarello Abstract Cell seeding technology is commonly used in the field of tissue engineering to enhance the performance of bioscaffolds and promote tissue regeneration. The age of cells used for ex vivo seeding to achieve maximal tissue regeneration has not been defined. Since rapid angiogenesis is the most critical step for tissue graft survival and success, we evaluated passage-dependent vascular endothelial growth factor (VEGF) expression in cultured smooth muscle cells (SMCs) obtained from urinary bladder and endothelial cell response to bladder SMCs. Levels of various VEGF isoforms mRNA expression and total VEGF secretion were determined by a semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay (ELISA) analysis, respectively. In vitro endothelial cell migration in Transwell® and capillary-like tube formation in MatrigelÔ were used to predict the ability of bladder SMCs to promote angiogenesis. VEGF produced by cultured bladder SMCs increased from passages 4 to 7, and decreased from passages 7 to 12 at both mRNA and protein levels. Endothelial cell migration as well as capillary-like tube formation correlated with levels of VEGF expression by bladder SMCs. Pre-incubation of endothelial cells with a VEGF receptor 1/2 inhibitor, SU5416, significantly reduced the number of capillary-like tubes in SMC-endothelial cell MatrigelÔ co-culture, and confirmed the involvement of VEGF in endothelial cell tube formation. Our results demonstrate that cell passage number is related to levels of VEGF production, which may translate to angiogenesis in engineered tissues. Copyright © 2009 John Wiley & Sons, Ltd. [source] Hypoxia-inducible factor-1 alpha and vascular endothelial growth factor expression in ischaemic colitis and ulcerative colitisALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 2006T. OKUDA Summary Background Hypoxia-inducible factor-1 alpha (HIF-1 alpha) is a transcriptional factor induced by ischaemic crisis in many tissues. Vascular endothelial growth factor (VEGF) is an important growth factor that plays a major role in angiogenesis. Aim We examined the aetiology and pathophysiology of human ischaemic colitis and ulcerative colitis from the viewpoint of the expression of these two ischaemic factors. Methods Thirty-two patients with ischaemic colitis, 16 with ulcerative colitis and 25 normal controls underwent colonoscopy. Biopsy samples were taken from a colitis lesion and a normal region in the same patient. In the normal controls, four biopsy samples were obtained from each subject. Biopsy samples were subjected to real-time polymerase chain reaction. Results Hypoxia-inducible factor and VEGF were overexpressed in ischaemic colitis lesions and quickly decreased to normal levels in the healing phase. In contrast, HIF but not VEGF was overexpressed in active ulcerative colitis lesions. In the remission phase of ulcerative colitis, VEGF decreased to low levels, although HIF was continuously overexpressed. Conclusions Overexpression of HIF and VEGF contribute to the tolerance of ischaemia in patients with active ischaemic colitis. The inconsistency in their expression might be associated with the chronic intestinal damage characteristic of ulcerative colitis. [source] Tumor cell-associated neuropilin-1 and vascular endothelial growth factor expression as determinants of tumor growth in neuroblastomaNEUROPATHOLOGY, Issue 3 2005Karen Marcus We sought to characterize the expression of vascular endothelial growth factor (VEGF) and its receptors in neuroblastoma (NBL) and to correlate the results with N-myc (MYCN) expression and in vivo growth of these tumors. Two representative human-derived NBL cell lines, SK-N-AS (AS) with low and SK-N-DZ (DZ) with a high MYCN copy number, were used for the study. We examined their proliferation, VEGF and VEGF receptor expression in vitro and xenograft tumor growth in vivo. In parallel, human NBL specimens were analyzed for expression of VEGF and neuropilin-1 (NRP-1). DZ cells exhibited a 4-fold higher proliferation rate than AS. In contrast, VEGF protein expression was significantly higher in AS cells. NRP-1 was the only VEGF receptor produced in AS and DZ cells in vitro and in vivo. Both AS and DZ cells formed tumors in athymic mice but AS tumors grew 3.5 times larger than DZ tumors and had larger diameter tumor vessels. VEGF and NRP-1 expression was also demonstrated in human NBL specimens. Our studies indicate that VEGF and VEGF receptor expression in NBL tumor cells are associated with tumor growth and that angiogenic factors may serve as a biological marker together with already established MYCN amplification. [source] Vascular endothelial growth factor expression in oligodendrogliomas: a correlative study withSainte-Anne malignancy grade, growth fractionand patient survivalNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2000P. Varlet Microangiogenesis is a delayed but crucial event in the malignant progression of oligodendrogliomas. Accord-ingly, in the new Sainte-Anne grading system of oligodendrogliomas, endothelial hyperplasia and contrast enhancement, both being indicators of microangiogenesis, are key criteria for the distinction of grade A from grade B tumours. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor: a strong correlation between VEGF expression, Sainte-Anne malignancy grade and patient outcome might thus be expected. In order to assess this hypothesis, VEGF immunostaining was performed in a series of 34 oligodendrogliomas that included 11 grade B and 23 grade A, of which nine became grade B during the study period (mean clinical and imaging follow-up: 41 months). VEGF expression correlated strongly with Sainte-Anne tumour grade (P < 0.001), and inversely with patient survival (P < 0.001) and recurrence-free survival (P = 0.002). One hundred per cent of grade B but only 17% of grade A were VEGF-positive. By contrast, the MIB-1 labelling index did not correlate with VEGF expression, total survival or recurrence-free survival. In accordance with the grading system, this study showed that, in oligodendrogliomas, VEGF expression and microangiogenesis are progression-related phenomena that confer on these tumours a growth advantage by presumably reducing hypoxia-induced apoptotic cell death. These findings might have important implications in the future for the indication and timing of anti-angiogenic therapies. [source] Epithelial,mesenchymal interactions in keloid pathogenesis modulate vascular endothelial growth factor expression and secretion,THE JOURNAL OF PATHOLOGY, Issue 1 2007CT Ong Abstract Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis during the wound healing process. As epithelial,mesenchymal interactions have been shown to regulate a plethora of genes in wound healing, we hypothesized that these interactions might have a role in modulating VEGF expression and angiogenesis. A two chamber co-culture model was used, wherein normal and keloid keratinocytes and fibroblasts were physically separated by membrane inserts while allowing cytokine diffusion. Cell lysates obtained from keratinocytes co-cultured with fibroblasts demonstrated increased expression of VEGF. An enzyme-linked immunosorbent assay (ELISA) showed significant increase in VEGF expression in co-culture conditioned media compared with controls. Additionally, the conditioned medium from keloid keratinocyte and fibroblast co-cultures increased proliferation and formation of complex three-dimensional capillary-like structures in human umbilical vein endothelial cells, emphasising the importance of epithelial,mesenchymal interactions in the angiogenic process. Immunostaining of keloid tissue localized VEGF in the basal layer of the epidermis and also demonstrated higher blood vessel density than normal skin. Keloid tissue extract also demonstrated increased expression of VEGF compared with normal skin. It is likely that epidermal VEGF exerts significant paracrine control over the dynamics and expression profile of underlying dermal fibroblasts. Addition of the inhibitors WP631, mitoxantrone, and Rapamycin to keloid keratinocyte and fibroblast co-cultures, downregulated secreted VEGF expression in a dose-dependent manner, suggesting therapeutic potential for these compounds in the treatment of keloid scars. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Rhinovirus upregulates matrix metalloproteinase-2, matrix metalloproteinase-9, and vascular endothelial growth factor expression in nasal polyp fibroblastsTHE LARYNGOSCOPE, Issue 9 2009Jong Hwan Wang MD Abstract Objectives/Hypothesis: Upregulation of matrix metalloproteinase (MMP) and vascular endothelial growth factor (VEGF) has been suggested to have an important role in the pathogenesis of nasal polyps (NPs). The aim of this study was to investigate the effect of rhinovirus (RV) infection on the expression of MMPs, tissue inhibitor of metalloproteinase (TIMP)-1, and VEGF in NP fibroblasts. Methods: NP fibroblasts (5 × 105 cells/mL) obtained from patients with chronic rhinosinusitis with nasal polyps (CRSwNP) were infected with RV serotype 16 (RV-16) for 4 hours. The RV-16 infection was confirmed by seminested reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization. After 48 hours, MMP-2, MMP-9, TIMP-1, and VEGF protein levels were measured from culture supernatants by enzyme-linked immunosorbent assay. The changes in the expression of MMP-2, MMP-9, TIMP-1, and VEGF mRNA were assayed by RT-PCR. Results: RV-16 infection significantly enhanced the gene and protein expressions of MMP-2, MMP-9, and VEGF in NP fibroblasts, whereas TIMP-1 expression was not significantly affected by RV-16. MMP-2, MMP-9, and VEGF protein expression increased by 2.39-, 2.99-, and 3.02-fold, respectively, in RV-infected NP fibroblasts compared to noninfected controls. RV-16 infection also significantly upregulated the expression of MMP-2, MMP-9, and VEGF mRNA by 1.27-, 1.70-, and 1.53-fold, respectively, compared to control levels. Conclusions: These in vitro findings suggest that RV infection may contribute to the pathogenesis of NP formation in patients with CRSwNP. Laryngoscope, 2009 [source] Experimental ischaemia-reperfusion injury induces vascular endothelial growth factor expression in the rat testisANDROLOGIA, Issue 4 2009H. Hashimoto Summary Testicular torsion causes ischaemia-reperfusion (I-R) injury of testis and might lead to male infertility. Its injury initiates a pathophysiological cascade, including an activation of inflammatory cytokines and generation of nitric oxide and other reactive oxygen species. Vascular endothelial growth factor (VEGF) mediates angiogenesis and promotes endothelial cell survival. The aim of our study was to investigate the time course expression of VEGF, VEGF-receptor (R)1, VEGF-R2, nitric oxide synthases (NOS) in experimental I-R injury of rat testis. In torsion side testis, the expression of VEGF protein and mRNA significantly increased in a time-dependent manner (P < 0.001 and P < 0.001, respectively). Although the expression of VEGF-R1 mRNA was increased in a similar way (P < 0.001), VEGF-R2 mRNA expression was not detected. In immunohistochemistry, the increase in VEGF protein staining was observed in testicular vascular endothelial cells and germ cells at 24 h after reperfusion. Significant activation of inducible NOS and endothelial NOS was investigated at 12 and 24 h after reperfusion (P < 0.01 and P < 0.001, respectively). This is the first report to show the time course expression of VEGF in experimental I-R rat testis. [source] Hypoxia-inducible factor-1, expression in experimental cirrhosis: correlation with vascular endothelial growth factor expression and angiogenesis,APMIS, Issue 7 2007SEVGI BOZOVA Angiogenesis progresses together with fibrogenesis during chronic liver injury. Hypoxia-inducible factor-1, (HIF-1,), a master regulator of homeostasis, plays a pivotal role in hypoxia-induced angiogenesis through its regulation of vascular endothelial growth factor (VEGF). The association between hypoxia, angiogenesis and VEGF expression has been demonstrated in experimental cirrhosis. However, expression of HIF-1, has yet to be reported. The aim of this study was to investigate the significance of HIF-1, expression during experimental liver fibrosis and the relationships between HIF-1, expression, VEGF expression and angiogenesis. Cirrhosis was induced in male Wistar rats by intraperitoneal administration of diethyl nitrosamine (DEN) (100 mg/kg, once a week). The serial sections from liver tissues were stained with anti-HIF-1,, anti-VEGF and anti-CD34 antibodies before being measured by light microscopy. Our results showed that HIF-1, expression gradually increases according to the severity of fibrosis (p<0.01). Moreover, its expression was found to be correlated with angiogenesis (r=0.916) and VEGF expression (r=0.969). The present study demonstrates that HIF-1, might have a role in the development of angiogenesis via regulation of VEGF during experimental liver fibrogenesis and suggests that this factor could be a potential target in the manipulation of angiogenesis in chronic inflammatory diseases of the liver. [source] Increased vascular endothelial growth factor expression, CD3-positive cell infiltration, and oxidative stress in premalignant lesions of the cervixCANCER, Issue 16 2009Yenddy Carrero MSc Abstract BACKGROUND: Vascular endothelial growth factor (VEGF) plays an important role in cervical intraepithelial neoplasia (CIN) progression. The occurrence of leukocytes has been documented in CIN; however, their role in VEGF production remains unknown. Oxidative stress has been involved in the progression of malignant neoplasias, but to the authors' knowledge tissue oxidative stress in CIN has not been documented. The objective of the current study was to investigate the expression of VEGF, leukocyte infiltration, leukocyte VEGF expression, and nitrogen/oxygen metabolism in cervical tissues from patients with CIN. METHODS: Indirect immunofluorescence was used to study the expression of VEGF and leukocyte infiltration in cervical samples from 55 patients with CIN and 7 normal controls. Superoxide anion (O2,) expression was determined by a cytochemical method, and tissue and serum nitric oxide by the Griess reaction. Human papillomavirus (HPV) DNA and HPV types were identified by the hybrid capture 2 HPV DNA test. RESULTS: Increased expression of VEGF was observed related to the progression of CIN. A significant increment of CD3 lymphocytes was found in CIN type 3 (CIN 3) and coexpression of CD3/VEGF and monocyte-macrophage/VEGF in CIN 2 and 3. Increased O2, -positive cells were found in CIN 2 and 3; however, tissue nitrate-nitrite content remained similar to controls. The incidence of HPV infection was 16% in patients with CIN. No significant differences were observed in the values of HPV-positive or HPV-negative patients. CONCLUSIONS: Different factors leading to cervical neoplasia progression may be involved in the evolution of CIN, and the presence of these factors is most likely not related to the HPV infection status. Cancer 2009. © 2009 American Cancer Society. [source] RhoC is essential for angiogenesis induced by hepatocellular carcinoma cells via regulation of endothelial cell organizationCANCER SCIENCE, Issue 10 2008Wei Wang The angiogenesis induced by tumor cells is essential for metastasis of hepatocellular carcinoma. Available information suggests that RhoC participates in angiogenesis through regulation of vascular endothelial growth factor expression in tumor cells. For its broad functions in cell migration and cytoskeletal organization, we hypothesized that RhoC regulating angiogenesis does not exclusively depend on regulation of vascular endothelial growth factor expression. To address this question, in the present study, we used a retroviral small interfering RNA approach to selectively knockdown the expression of RhoC in a neovascularization model in vivo and in vitro. Our present results indicate that RhoC is the downstream regulator of vascular endothelial growth factor in endothelial cells and is essential for angiogenesis induced by vascular endothelial growth factor, notwithstanding that RhoC regulates the expression of vascular endothelial growth factor in tumor cells. Furthermore, we show that knockdown of RhoC is associated with the inhibition of invasion and migration but not apoptosis of endothelial cells. Knockdown of RhoC results in inhibition of endothelial cell organization through restraining the reorganization of F-actin filaments, which represses endothelial cell network and sprout formation. In conclusion, our results demonstrate that knockdown of RhoC inhibits angiogenesis induced by tumor cells not only through effecting the release of vascular endothelial growth factor, but also through inhibiting endothelial cell migration and organization, which implies that it blocks tumor metastasis by specifically inhibiting RhoC in endothelial cells. (Cancer Sci 2008; 99: 2012,2018) [source] Clinical and histological findings after intravitreal injection of bevacizumab (Avastin®) in a porcine model of choroidal neovascularizationACTA OPHTHALMOLOGICA, Issue 3 2010Nathan Lassota Abstract. Purpose:, To examine the effect of intravitreally injected bevacizumab (Avastin®) on the histological and angiographic morphology of choroidal neovascularization (CNV) in a masked and placebo-controlled animal study. Methods:, Choroidal neovascularization was induced surgically in 11 porcine eyes by perforating Bruch's membrane with a retinal perforator. After closure of the ports used for the vitrectomy, which was performed to facilitate the Bruch's membrane rupture, 0.05 ml of either bevacizumab or Ringer-Lactat (placebo) was injected into the vitreous cavity. Eyes were enucleated after 14 days. Fundus photographs and fluorescein angiograms (FAs) were obtained immediately prior to enucleation. Sections of formalin- and paraffin-embedded eyes were examined by light microscopy and by immunohistochemical staining. Results:, Placebo-injected eyes exhibited the highest propensity to leak, with five of six eyes leaking on FA, whereas only one of five bevacizumab-injected eyes exhibited leakage. On histological examination, all 11 eyes contained CNV membranes of similar size, regardless of treatment. The number of vascular endothelial cells was significantly reduced (p = 0.03) in CNV membranes from eyes that had been injected with bevacizumab when compared with CNV membranes from placebo-injected eyes. There was a trend towards more retinal pigment epithelium cells (p = 0.16) and fewer glial fibres (p = 0.08) in membranes from bevacizumab-treated eyes compared with placebo-treated eyes. Bevacizumab was identified immunohistochemically in the inner limiting membrane (ILM) and to a lesser degree in the remaining retina. Strong staining was also detected in both retinal blood vessels and entire CNV membranes with no cellular predisposition. Vascular endothelial growth factor expression was found in the CNV membranes, in the ILM, in the ganglion cell layer, in Müller cells throughout the neuroretina and in retinal blood vessels. Conclusions:, Bevacizumab significantly reduced the proliferation of vascular endothelial cells in CNV membranes and showed a strong trend towards a reduction of leakage from these membranes. After a single injection, bevacizumab did not exhibit a size reducing effect on CNV, but it was still present in the membranes 14 days after intravitreal injection. [source] Alveolar Ridge Regeneration with Equine Spongy Bone: A Clinical, Histological, and Immunohistochemical Case SeriesCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2009Danilo Alessio Di Stefano DDS ABSTRACT Background: In the case of localized ridge atrophy, a ridge augmentation procedure, with the use of bone substitutes and barrier membranes, may then be necessary. Purpose: The aim of the present study was a clinical, histological, and immunohistochemical evaluation of an equine spongy bone in alveolar ridge augmentation procedures. Materials and Methods: Five patients showing horizontal mandibular ridge defects participated in this study. A ridge augmentation was performed through an onlay apposition of equine bone covered by a titanium-reinforced membrane. After 6 months of healing, five bone cores from nonaugmented sites (control) and five from augmented sites (test) were retrieved. Results: In test sites, no postoperative complications occurred. Horizontal bone width increased from ,4 to ,7 mm. In control sites, the newly formed bone represented 33%, and in test sites, 35% of the total area. The mean value of the microvessel density was 25.6 +/, 3.425 per mm2 in controls, while 33.3 +/, 2.5 vessels per mm2 in the test sites were found (p < .05). Both groups showed a high intensity (++) of vascular endothelial growth factor expression in the newly formed bone, while a low intensity (+) was found in the mature bone. Conclusion: Equine bone appeared to be biocompatible and to be associated with new vessel ingrowth. Within the limits of the small sample size, the present study indicated that equine bone could be used in mandibular ridge augmentations. [source] | ||||||||||||||||||||||||||||