Expression of vascular endothelial growth factor and its receptors VEGFR-1 and 2 in gastrointestinal stromal tumors,leiomyomas and schwannomas

AIM： To investigate the role of vascular endothelial growth factor （VEGF/and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal strornal tumors （GISTs）. METHODS： Thirty-three GISTs, 15 leiomyomas and 6 schwannomas were examined by immunohistochemistry in this study. RESULTS： VEGF protein was expressed in the cytoplasm of tumor cells, and VEGFRol and 2 were expressed both in the cytoplasm and on the membrane of all tumors. Irnrnunohistochernical staining revealed that 26 GISTs （78.8%）, 9 leiornyornas （60.0%） and 3 schwannornas （50.0%/were positive for VEGF; 24 GISTs （72.7%/, 12 leiornyornas （80.0%） and 4 schwannornas （66.7%） were positive for VEGFR-1; 30 GISTs （90.9%/, 5 leiornyornas （33.3%/and 4 schwannornas （66.7%） were positive for VEGFR-2. VEGFR-2 expression was statistically different between GISTs and leiomyomas （P 〈 0.0001）. However, there was no correlation between the expression of VEGF pathway componenets and the clinical risk categories. CONCLUSION： Our results suggest that the VEGF pathway may play an important role in the differentiation of GISTs, leiomyomas and schwannomas.

Molecular Modeling Studies of Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitors Combining Molecular Docking and 3D-QSAR Methods

The vascular endothelial growth factor （VEGF） and its receptor tyrosine kinases VEGFR-2 or kinase insertdomain receptor （KDR） have emerged as attractive targets for the design of novel anticancer agents. In the present work, molecular docking method combined with three dimensional quantitative structure-activity relationships （comparative molecular field analysis （CoMFA） and comparative molecular similarity indice analysis （CoMSIA）） to analyze the possible interactions between KDR and those derivatives which acted as selective inhibitors. The CoMFA and CoMSIA models gave a cross-validated coefficient Q2 of 0.713 and 0.549, non-cross-validated R2 values of 0.974 and 0.878, and predicted R2 values of 0.966 and 0.823, respectively. The 3D contour maps generated by the CoMFA and CoMSIA models were used to identify the key structural requirements responsible for the biological activity. The information obtained from 3D-QSAR and docking studies were very helpful to design novel selective inhibitors of KDR with desired activity and good chemical property.

Increased expressions of vascular endothelial growth factor(VEGF),VEGF-C and VEGF receptor-3 in prostate cancer tissue are associated with tumor progression

Aim： To investigate the differences in microvessel densities （MVD） and the expressions of vascular endothelial growth factor （VEGF）, VEGF-C and VEGF receptor-3 （VEGFR-3） between prostate cancer （PCa） tissues and adjacent benign tissues, and to explore the correlations among MVD, Jewett-Whitmore staging, Gleason scores and expressions of VEGF, VEGF-C and VEGFR-3 in the progression of PCa. Methods： An immunohistochemical approach was adopted to detect the expressions of CD34, VEGF, VEGF-C and VEGFR-3 in both cancer areas and peripheral benign areas of 71 primary prostatic adenocarcinoma specimens. A statistic analysis was then performed according to the experimental and clinic data. Results： Significantly upregulated expressions of VEGF, VEGF-C and VEGFR-3 were all found in malignant epithelium/cancer cells compared with adjacent benign epithelium （P 〈 0.01）. Patients in stage D had a significantly higher score than patients in stage A, B or C when comparing the expression of VEGF-C or VEGFR-3 in the tumor area （P 〈 0.01）. In addition, significant correlations were observed between Jewett-Whitmore staging and VEGF-C （rs = 0.738, P 〈 0.01）, clinical staging and VEGFR-3 （rs = 0.410, P 〈 0.01）, VEGF-C and Gleason scores （rs = 0.401, P 〈 0.01）, VEGFR-3 and Gleason scores （rs = 0.581, P 〈 0.001） and MVD and VEGF （rs = 0.492, P 〈 0.001）. Conclusion： Increased expressions of VEGF and VEGF-C were closely associ- ated with progression of PCa. The main contribution of increased VEGF expression for PCa progression was to upregulate MVD, which maintained the growth advantage of tumor tissue. However, the chief role of increased expressions of VEGF-C and VEGFR-3 was to enhance lymphangiogenesis and provide a main pathway for cancer cells to disseminate. （Asian J Androl 2006 Mar; 8： 169-175）

Association of vascular endothelial growth factor-634G/C and receptor for advanced glycation end products G82S gene polymorphisms with diabetic retinopathy

AIMTo investigate the association of receptor for advanced glycation end products (RAGE) G82S and vascular endothelial growth factor (VEGF) -634 G/C gene polymorphisms with diabetic retinopathy (DR).METHODSOur cross-sectional study included 61 diabetic patients, 12 of them had proliferative diabetic retinopathy (PDR), 15 had non proliferative diabetic retinopathy (NPDR), 34 had no diabetic retinopathy (NDR) and 61 healthy controls. Participants were tested for RAGE G82S and VEGF -634 G/C polymorphisms by polymerase chain reaction-restriction fragment length polymorphism.RESULTSWe found a significant association between VEGF -634 G/C polymorphism and PDR as PDR patients had increased incidence of VEGF -634 CC genotype compared to NDR patients [odds ratio for CC vs (GC+GG)=6.5, 95% CI=1.5-27.8, P=0.021]. Also VEGF -634 CC genotype and C allele were significantly higher in the PDR than in NPDR patients, which is a novel finding in our study (P=0.024, 0.009 respectively). The mean triglycerides level was significantly higher in diabetic patients with CC genotype (P=0.01) as compared to patients with other genotypes. All cases and control subjects were of the same heterozygous RAGE 82G/S genotype.CONCLUSIONPatients carrying VEGF -634 C polymorphism have a higher risk of PDR development, so VEGF -634 G/C polymorphism could be used as a predictive marker for PDR in diabetic patients. We could not find a significant association between RAGE G82S polymorphism and DR.

Expression of Vascular Endothelial Growth Factor-C and Vascular Endothelial Growth Factor Receptor-3 in Ovarian Epithelial Tumors

Objective： To explore the role of vascular endothelial growth factor-C （VEGF-C） in the process of angiogenesis, lymphangiogenesis and lymphatic metastasis in epithelial ovarian tumors. Methods： In situ hybridization and immunohistochemical staining for VEGF-C were performed in 30 epithelial ovarian carcinomas, 9 borderline tumors and 26 benign tumors. Endothelial cells were immunostained with anti-VEGFR-3 pAb and anti-CD31 mAb, and VEGFR-3 positive vessels and microvessel density （MVD） were assessed by image analysis. Results： VEGF-C mRNA and protein expression were detected in cytoplasm of carcinoma cells. VEGF-C mRNA and protein expression in ovarian epithelial carcinomas were significantly higher than those in borderline tumors and benign tumors （P〈0.05 or P〈0.01）. In ovarian epithelial carcinomas, VEGF-C protein expression, VEGFR-3 positive vessels and MVD were significantly higher in the cases of clinical stage Ⅲ-Ⅳ and with lymph node metastasis than those of clinical stage Ⅰ-Ⅱ and without lymph node metastasis respectively （P〈0.05 or P〈0.01）. VEGFR-3 positive vessels and MVD were significantly higher in VEGF-C protein positive tumors than negative tumors （P〈0.05）. VEGFR-3 positive vessels was significantly correlated with MVD（P〈0.01）. Conclusion： VEGF-C might play a role in lymphatic metastasis via lymphangiogenesis and angiogenesis in epithelial ovarian tumors, and VBEGF-C could be used as a biologic marker of metastasis in ovarian epithelial tumors.

Activation of STAT3 signaling in human stomach adenocarcinoma drug-resistant cell line and its relationship with expression of vascular endothelial growth factor

AIM: To investigate the difference in activation of STAT3 signaling between two human stomach adenocarcinoma cell lines: 5-fluorouracil resistant cell line and its parental cell line, and to evaluate its relationship with the expression of vascular endothelial growth factor (VEGF). METHODS: Western blot and electrophoretic mobility shift assay (EMSA) were used to detect the expression of phospho-STAT3 protein and constitutive activation of STAT3 in two human stomach adenocarcinoma cell lines, 5-fluorouracil resistant cell line SGC7901/R and its parental cell line SGC7901, respectively. The mRNA expression of VEGF was analysed by semi-quantitative RT-PCR. The expressive intensity of VEGF protein was measured by immunocytochemistry. RESULTS: The expressions of phospho-STATS protein and constitutive activation of STAT3 between two human stomach adenocarcinoma cell lines were different. Compared with the parental cell line SGC7901, the STAT3DNA binding activity and the expressive intensity of phospho-STAT3 protein were lower in the drug-resistant cell line SGC7901/R. The expression levels of VEGF mRNA and its encoded protein were also decreased in drugresistant cell line. CONCLUSION: Over-expression of VEGF may be correlated with elevated STAT3 activation in parental cell line. Lower VEGF expression may be correlated with decreased STAT3 activation in resistant cell line, which may have resulted from negative feedback regulation of STAT signaling.

Expression of thymidine kinase mediated by a novel non-viral delivery system under the control of vascular endothelial growth factor receptor 2 promoter selectively kills human umbilical vein endothelial cells

AIM: To investigate the killing efficiency of a recombinant plasmid containing a thymidine kinase (TK) domain insert driven by the vascular endothelial growth factor receptor 2 (VEGFR2) promoter (KDR) on vascular endothelial cells.METHODS: The KDR-TK fragment was extracted from pBluescript Ⅱ KDR-TK plasmid by enzymatic digestion with Xho I and Sal I. The enhanced green fluorescence protein (EGFP) carrier was extracted from pEGFP by the same procedure. The KDR-TK was inserted into the pEGFP carrier to construct pEGFP-KDR-TK. Using ultrasound irradiation and microbubble, pEGFP-KDR-TK was transferred into human umbilical vein endothelial cells (HUVECs). The transient infection rate was estimated by green fluorescent protein (GFP) expression. Transfected HUVECs, non-transfected HUVECs, and HepG2 cells were cultured in the presence of different concentrations of ganciclovir (GCV), and the killing efficacy of HSV-TK/GCV was analyzed by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) assay. RESULTS: The recombinant pEGFP-KDR-TK was successfully constructed by inserting the KDR-TK fragment into the pEGFP carrier. Transfected HUVECs showed cytoplasmic green fluorescence, and the transient transfection rate was about 20.3%. Pools of G418-resistant cells exhibited a higher sensitivity to theprodrug/GCV compared to non-transfected HUVECs or non-transfected HepG2 cells, respectively. CONCLUSION: KDR promoter and the suicide gene/prodrug system mediated by diagnostic ultrasound combined with microbubble can significantly kill HUVECs. Such therapy may present a novel and attractive approach to target gene therapy on tumor vessels.

Increased serum levels of soluble CD146 and vascular endothelial growth factor receptor 2 in patients with exudative age-related macular degeneration

AIM: To investigate serum levels of soluble CD146(s CD146) and vascular endothelial growth factor receptor 2(VEGFR2) in patients with age-related macular degeneration(AMD). METHODS: Eighty-eight patients with exudative AMD and 45 sex-and age-matched healthy controls were enrolled in this study conducted in China. Serum samples was obtained from the patients with exudative AMD and from the controls. Serum sCD146 and VEGFR2 protein levels were measured using an enzyme-linked immunosorbent assay.RESULTS: We found that serum sCD146 and VEGFR2 protein levels were significantly higher in the patients with exudative AMD group than in the controls(t=3.859, P<0.001 and t=3.829, P<0.001, respectively). Serum sCD146 levels were significantly higher in patients with classic choroidal neovascularization(CNV) than in those with occult CNV(t=9.899, P<0.001). There was a significant difference in the trend for exudative AMD in the highest versus lowest quartile of circulating sCD146 levels(χ2=10.29, P=0.001). The receiver operating characteristic curve analysis showed that the area under the curve was 0.696 for s CD146(95%CI: 0.601-0.791) with an optimum diagnostic cut-off value of 157.16 ng/mL, a sensitivity of 55.7%, and a specificity of 82.2%.CONCLUSION: The serum sCD146 level increases and may be a biomarker for exudative AMD.

Expression of p-STAT3 and vascular endothelial growth factor in MNNG-induced precancerous lesions and gastric tumors in rats

AIM: To investigate the dynamic expression of p-signal transducer and activator of transcription 3 (STAT3) and vascular endothelial growth factor (VEGF) in the formation of gastric tumors induced by drinking water containing N-methyl-N’-nitro-N-nitrosoguanidine (MNNG) in Wistar rats. METHODS: One hundred and twenty Wistar rats were randomly divided into two groups (60 in each group): Control group and Model group. The rats in each group were then randomly divided into three groups (20 in each group): C/M15, C/M25 and C/M40 (15, 25 and 40 represent the number of feeding weeks from termination). Rats in the control group received normal drinking water and rats in the model group received drinking water containing 100 μg/mL MNNG. Stomach tissues were collected at the end of the 15th, 25th and 40th week, respectively, for microscopic measurement using hematoxylin and eosin staining. The expression of p-STAT3 and VEGF in different pathological types of gastric tissue, including normal, inflammation, atrophy, hyperplasia and gastric stromal tumor, was observed by immunohistochemistry and Western blot, and the corelation between p-STAT3 and VEGF was analyzed. RESULTS: (1) The expression of p-STAT3 in tissue with gastritis, atrophy, dysplasia and gastric stromal tumor were significantly increased in the model group compared with the control group (2.5 ± 1.0, 2.75 ± 0.36, 6.2 ± 0.45, 5.67 ± 0.55 vs 0.75 ± 0.36, P = 0.026, 0.035, 0.001, 0.002, respectively); the expression of p-STAT3 in tissue with dysplasia was higher than that in samples with gastritis or atrophy (6.2 ± 0.45 vs 2.5 ± 1.0, P = 0.006; 6.2 ± 0.45 vs 2.75 ± 0.36, P = 0.005, respectively); however, the expression of p-STAT3 in gastritis and atrophy was not significantly different (P > 0.05); (2) the expression of VEGF in tissue with gastritis, atrophy, dysplasia and gastric stromal tumor was significantly increased in the model group compared with normal gastric mucosa; and the expression of VEGF in tissue with dysplasia was higher than that in tissue with inflammation and atrophy (10.8 ± 1.96 vs 7.62 ± 0.25, P = 0.029; 10.8 ± 1.96 vs 6.26 ± 0.76, P = 0.033, respectively); similarly, the expression of VEGF in tissue with gastritis and atrophy was not significantly different (P > 0.05); and (3) the expression of VEGF was positively correlated with p-STAT3. CONCLUSION: p-STAT3 plays an important role in gastric cancer formation by regulating the expression of VEGF to promote the progression of gastric tumor from gastritis.

Prognostic value of vascular endothelial growth factor receptor 1 and classⅢβ-tubulin in survival for nonmetastatic rectal cancer

AIM To assess the long-term prognostic value of vascular endothelial growth factor receptor 1(VEGFR1)and classⅢβ-tubulin(TUBB3)mRNA expression in nonmetastatic rectal cancer.METHODS A total of 75 consecutive patients with non-metastatic rectal cancer from March 2004 to November 2008 were analyzed retrospectively at our institute.The mRNA expressions of VEGFR1 and TUBB3 were detected by multiplex branched DNA liquid-chip technology.The Cutoff Finder application was applied to determine cutoff point of mRNA expression.SPSS software version 22.0was used for analysis.RESULTS The median follow-up was 102.7 mo(range,6-153.6).Theχ~2 and Fisher’s exact tests showed that VEGFR1expression was related to lymph node metastasis(P=0.013),while no relationships between TUBB3 and clinicopathological features were observed.Univariate analysis showed that T stage,lymph node metastasis,tumor differentiation,VEGFR1 and TUBB3 mRNA expression were correlated to overall survival(OS)(P=0.048,P=0.003,P=0.052,P=0.003 and P=0.015,respectively).Also,lymph node metastasis and VEGFR1expression independently influenced OS by multivariate analysis(P=0.027 and P=0.033).VEGFR1 expression was positively correlated with TUBB3(P=0.024).The patients with low expression of both TUBB3 and VEGFR1 presented a better OS(P=0.003).In addition,the receiver operating characteristic analysis suggested that the combination of lymph node metastasis and VEGFR1 had a more favorable prognostic value(P<0.001).CONCLUSION VEGFR1 expression and lymph node metastasis independently and jointly affect survival.Moreover,low expression of VEGFR1 and TUBB3 presented a better OS in patients with non-metastatic rectal cancer,which might serve as a potential prognostic factor.

Vascular endothelial growth factor/platelet-derived growth factor receptor pathway is involved in bone marrow mesenchymal stem cell differentiation and directional migration toward gliomas

BACKGROUND： Vascular endothelial growth factor （VEGF） induces bone marrow-derived mesenchymal stem cell （BMSC） differentiation into vascular endothelial-like cells and promotes BMSC migration toward gliomas. However, the molecular mechanisms by which VEGF induces BMSC differentiation and migration remain poorly understood. OBJECTIVE; To investigate the role of platelet-derived growth factor （PDGF） receptor （PDGFR） in BMSC differentiation and migration induced by VEGE DESIGN, TIME AND SETTING： A parallel, controlled, in vitro experiment was performed at the Molecular Neurobiology ＆ Neural Regeneration and Repairing Laboratory, Anhui Provincial Hospital of Anhui Medical University, China from June 2008 to March 2009. MATERIALS： U87 glioma cells were purchased from Shanghai Institutes for Biological Sciences; mouse anti-human PDGFR and VEGF receptor （VEGFR） monoclonal antibodies were purchased from Peprotech, USA. METHODS： Isolated BMSCs were precultured with neutralizing antibody for VEGFR-1, VEGFR-2, PDGFR-α, and PDGFR-β to block biological activity of related receptors, followed by induced differentiation with 50μg/L VEGF. BMSCs induced with 50μg/L VEGF alone served as the VEGF-induced group. The control group remained untreated. MAIN OUTCOME MEASURES： Cell surface markers were identified by flow cytometry; BMSC surface cytokine receptor expression was detected by reverse transcription-polymerase chain reaction; the Transwell model was used to observe cell migration. RESULTS： After blocking the PDGFR, VEGF did not induce BMSC cell surface marker CD-31 or von Willebrand factor （vWF） expression. However, inhibition with VEGF receptor blocking agents, VEGF induced BMSCs to express CD-31 and vWE Following inhibition of the PDGFR, the number of cells migrating through the polycarbonate membrane Transwell chamber was decreased, as well as the number of BMSCs migrating to glioma cells. However, through the use of VEGF receptor blocking agents, the number of migrating cells remained unchanged. VEGF preculture increased the number of BMSCs migrating to gliomas. CONCLUSION： VEGF interacts with PDGFRs on the BMSC surface to attract BMSC directional migration and induce BMSC differentiation. The VEGF/PDGFR pathway participates in BMSC directional migration to glioma. VEGF pretreatment increased efficiency of BMSC migration to glioma.

Integrin binding peptides facilitate growth and interconnected vascular-like network formation of rat primary cortical vascular endothelial cells in vitro

Neovascularization and angiogenesis in the brain are important physiological processes for normal brain development and repair/regeneration following insults. Integrins are cell surface adhesion receptors mediating important function of cells such as survival, growth and development during tissue organization, differentiation and organogenesis. In this study, we used an integrin-binding array platform to identify the important types of integrins and their binding peptides that facilitate adhesion, growth, development, and vascular-like network formation of rat primary brain microvascular endothelial cells. Brain microvascular endothelial cells were isolated from rat brain on post-natal day 7. Cells were cultured in a custom-designed integrin array system containing short synthetic peptides binding to 16 types of integrins commonly expressed on cells in vertebrates. After 7 days of culture, the brain microvascular endothelial cells were processed for immunostaining with markers for endothelial cells including von Willibrand factor and platelet endothelial cell adhesion molecule. 5-Bromo-2′-dexoyuridine was added to the culture at 48 hours prior to fixation to assess cell proliferation. Among 16 integrins tested, we found that α5β1, αvβ5 and αvβ8 greatly promoted proliferation of endothelial cells in culture. To investigate the effect of integrin-binding peptides in promoting neovascularization and angiogenesis, the binding peptides to the above three types of integrins were immobilized to our custom-designed hydrogel in three-dimensional(3 D) culture of brain microvascular endothelial cells with the addition of vascular endothelial growth factor. Following a 7-day 3 D culture, the culture was fixed and processed for double labeling of phalloidin with von Willibrand factor or platelet endothelial cell adhesion molecule and assessed under confocal microscopy. In the 3 D culture in hydrogels conjugated with the integrin-binding peptide, brain microvascular endothelial cells formed interconnected vascular-like network with clearly discernable lumens, which is reminiscent of brain microvascular network in vivo. With the novel integrin-binding array system, we identified the specific types of integrins on brain microvascular endothelial cells that mediate cell adhesion and growth followed by functionalizing a 3 D hydrogel culture system using the binding peptides that specifically bind to the identified integrins, leading to robust growth and lumenized microvascular-like network formation of brain microvascular endothelial cells in 3 D culture. This technology can be used for in vitro and in vivo vascularization of transplants or brain lesions to promote brain tissue regeneration following neurological insults.

Serum vascular endothelial growth factor receptor-2 and adropin levels in age-related macular degeneration

AIM： To investigate the serum levels of vascular endothelial growth factor receptor-2（VEGFR-2） and adropin in age-related macular degeneration（AMD）patients.·METHODS： Ninety-eight AMD patients were included in the study. Seventy-eight age- and sex-matched healthy volunteers were recruited as the control group.Fundus florescein angiography and optical coherence tomography were performed to assess the posterior segment details. Serum VEGFR-2 and adropin levels were measured using enzyme-linked immunosorbent assays and compared between the study groups.· RESULTS： AMD group had significantly increased foveal retinal thickness, serum LDL and HDL levels and significantly decreased subfoveal choroidal thickness（P =0.01, 0.047, 0.025 and 〈0.001, respectively）. Serum VEGFR-2level revealed a significant decrease in AMD patients compared to controls（26.48 ±6.44 vs 30.42 ±7.92 ng/m L,P 〈0.001）. There was an insignificant increase in serum adropin level in AMD patients（6.17±3.19 vs 5.79±2.71 ng/m L,P =0.4）. Serum level of VEGFR-2 in AMD patients had a significant negative correlation with foveal retinal thickness（r =-0.226, P =0.025） and a significant positive correlation with subfoveal choroidal thickness（r=0.2, P=0.048）.·CONCLUSION： The current study demonstrated that the decreased serum VEGFR-2 level may be considered in the development of AMD. Adropin does not seem to play a role in the pathogenesis of AMD.

Expression of vascular endothelial growth factor and its two receptors in normal human endometrium

Objectives: We try to demonstrate the expression of vascular endothelial growthfactor (VEGF) and its receptors, flt-1 and KDR, in normal human emdometrium duringthe menstrual cycle.Methods: Immunohistochemical method was used to observe the expression ofVEGF and its two receptors in emdometrium throughout the normal menstrual cyclemeanwhile the isoforms of VEGF were also detected by Western blot analysis. The en-dothelial cells of micro-vessels were marked with Ⅷ factor antibody.Results: VEGF and its receptors existed in endometrial glandular, stromal and vas-cular endothelial cells of human endometrium. Their expressions were higher in the mid-secretory phase of menstrual cycle and highest at menstruation. VEGF121 and VEGF165were the predominant isoforms in normal human endometrium.Conclusion: The expression of VEGF and its two receptors showed cycle-dependentin human endometrium, probably involved in embryonic implantation and endometrialproliferation and differentiation.

Streptozotocin induced diabetic retinopathy in rat and the expression of vascular endothelial growth factor and its receptor

·AIM: To establishtherat model of streptozotocin (STZ)- induced diabetic retinopathy (DR), which is the most common cause of visual loss and blindness in patients with diabetes, and observe the gene expression of vascular endothelial growth factor (VEGF) and its receptors during the development of DR. ·METHODS: A rat model of diabetes was established by intraperitoneal injection of STZ. The diabetic rats were housed for 2, 3 and 4 months after the development of diabetes. Retinal histopathological observation was performed. The retinal vessels were observed by immunofluorescence staining by CD31. The mRNA expression of VEGF, VEGF receptor 1 and 2 (VEGFR1/2) in rat retina was detected by reverse transcription - polymerase chain reaction (RT-PCR) analysis. · RESULTS: Retinal histopathological observation showed the morphological changes of inner nuclear layer (INL) and outer nuclear layer (ONL) at any time -point, and also demonstrated the increased new vessels at both 3, 4 months after the development of diabetes. The CD31 staining results showed that the number of vessels was increased in the retinas of diabetic rats at both 3 and 4 months after the development of diabetes. As compared to the normal rats, the mRNA expression of VEGF was increased in retinas of diabetic rats at 3 months after the development of diabetes, while VEGFR1 and VEGFR2 mRNA expression was increased at 2, 3 and 4 months after the development of diabetes.·CONCLUSION:Takentogether,ourresultsdemonstrated that DR was occurred at 3 months after the development of diabetes, and the mRNA expression of VEGF, VEGFR1 and VEGFR2 were increased in the process of DR. The present study further evidenced the involvement of VEGF and its receptors in the process of DR. ·

Inhibitory effect of interferon-α-2b on expression of cyclooxygenase-2 and vascular endothelial growth factor in human hepatocellular carcinoma inoculated in nude mice

AIM： To evaluate the effects of interferon-α-2b （IFN- α-2b） on expression of cyclooxygenase-2 （COX-2） and vascular endothelial growth factor （VEGF） in human hepatocellular carcinoma （HCC） inoculated in nude mice and to study the underlying mechanism of IFN-α- 2b against HCC growth. METHODS： Thirb/-two nude mice bearing human HCC were randomly divided into four groups （n = 8）. On the 10th day after implantation of HCC cells, the mice in test groups （groups A, B and C） received IFN-α- 2b at a serial dose （10000 IU for group A, 20000 IU for group B, 40000 IU for group C sc daily） for 35 d. The mice in control group received normal saline （NS）. The growth conditions of transplanted tumors were observed. Both genes and proteins of COX-2 and VEGF were detected by RT-PCR and Western blot. Apoptosis of tumor cells in nude mice was detected by TUNEL assay after treatment with IFN-α-2b. RESULTS： Tumors were significantly smaller and had a lower weight in the IFN-α-2b treatment groups than those in the control group （P 〈 0.01）, and the tumor growth inhibition rate in groups A, B and C was 27.78%, 65.22% and 49.64%, respectively. The expression levels of both genes and proteins of COX-2 and VEGF were much lower in the IFN-α-2b treatment groups than in the control group （P 〈 0.01）. The apoptosis index （AI） of tumor cells in the IFN-α-2b treatment groups was markedly higher than that in the control group （P 〈 0.01）. Group B had a higher inhibition rate of tumor growth, a lower expression level of COX-2 and VEGF and a higher AI than groups A and C （P 〈 0.05）, but there was no significant difference between groups A and C. CONCLUSION： The inhibitory effects of IFN-α-2b on implanted tumor growth and apoptosis may be associated with the down-regulation of COX-2 and VEGF expression. There is a dose-effect relationship. The medium dose of IFN-α-2b for inhibiting tumor growth is 20 000 IU/d.

Three-dimensional-arterial spin labeling perfusion correlation with diabetes-associated cognitive dysfunction and vascular endothelial growth factor in type 2 diabetes mellitus rat

BACKGROUND Type 2 diabetes mellitus(T2DM) has been strongly associated with an increased risk of developing cognitive dysfunction and dementia.The mechanisms of diabetes-associated cognitive dysfunction(DACD) have not been fully elucidated to date.Some studies proved lower cerebral blood flow(CBF) in the hippocampus was associated with poor executive function and memory in T2DM.Increasing evidence showed that diabetes leads to abnormal vascular endothelial growth factor(VEGF) expression and CBF changes in humans and animal models.In this study,we hypothesized that DACD was correlated with CBF alteration as measured by three-dimensional(3D) arterial spin labeling(3D-ASL) and VEGF expression in the hippocampus.AIM To assess the correlation between CBF(measured by 3D-ASL and VEGF expression) and DACD in a rat model of T2DM.METHODS Forty Sprague-Dawley male rats were divided into control and T2DM groups.The T2DM group was established by feeding rats a high-fat diet and glucose to induce impaired glucose tolerance and then injecting them with streptozotocin to induce T2DM.Cognitive function was assessed using the Morris water maze experiment.The CBF changes were measured by 3D-ASL magnetic resonance imaging.VEGF expression was determined using immunofluorescence.RESULTS The escape latency time significantly reduced 15 wk after streptozotocin injection in the T2DM group.The total distance traveled was longer in the T2DM group;also,the platform was crossed fewer times.The percentage of distance in the target zone significantly decreased.CBF decreased in the bilateral hippocampus in the T2DM group.No difference was found between the right CBF value and the left CBF value in the T2DM group.The VEGF expression level in the hippocampus was lower in the T2DM group and correlated with the CBF value.The escape latency negatively correlated with the CBF value.The number of rats crossing the platform positively correlated with the CBF value.CONCLUSION Low CBF in the hippocampus and decreased VEGF expression might be crucial in DACD.CBF measured by 3D-ASL might serve as a noninvasive imaging biomarker for cognitive impairment associated with T2DM.

The effect of Chinese herbal medicine“heche assisted pregnancy recipe”on endometrial estrogen and progesterone receptor,proliferating cell nuclear antigen and vascular endothelial growth factor in the patients with infertility

Objectives:To investigate the effect of Chinese herbal medicine"heche assisted preg-nancy recipe (HCAPR)" on estrogen receptor(ER), progesterone receptor (PR), pro-lifierating cell nuclear antigen(PCNA) and vascular endothelial growth factor (VEGF)in endometrium of infertile women.Methods: The S-P immunohistochemical assay was used to observe expression ofER, PR , PCNA and VEGF in late proliferative phase before and after the HCAPR treat-ment.Results: After the treatment, the expression of ER,PR,PCNA and VEGF in nucleiof glandular epithelium and stromal cells was significantly stronger (all P＜0. 001) re-spectively than that before treatment , especially the expression of PCNA and VEGF.Conclusions: These results suggest that traditional Chinese medicine HCAPR oftonifying kidney and regulating menstruation increased the synthesis of ER,PR, PCNAand VEGF, which may promote normal growth and development of the endometrium ,improve the micro-environment of the endometrium, and enhance uterine receptivity.The evidence may provide theoretical basis for therapy infertility with Chinese herbalmedicine.

Induction of vascular endothelial growth factor receptor expression in human umbilical vein endothelial cells after repeated bevacizumab treatment in vitro

AIM： To investigate the mechanism underlying the loss of responsiveness to anti-vascular endothelial growth factor（VEGF） treatment after repeated injections for choroidal neovascularization, VEGF and VEGF receptor（VEGFR） expressions were evaluated following repeated bevacizumab treatments in hypoxic human umbilical vein endothelial cells（HUVECs） in vitro.METHODS： HUVECs were incubated under hypoxic conditions in two media of different bevacizumab concentrations（1.0 or 2.5 mg/m L） for 17 h, and then in a new medium without bevacizumab for 7h. This procedure was repeated twice more. A culture with an identical volume of excipients served as the control. Cytotoxicity and cell proliferation were assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide and Ki-67 assays, respectively. Levels of VEGF and VEGFR were assessed using enzyme-linked immunosorbent assay and Western blot respectively.RESULTS： Cytotoxic effects were not reported for either bevacizumab concentration. Cell proliferation was not reduced after anti-VEGF treatments. VEGF level after single treatment was significantly higher than that of the control and after repeated treatments. Phosphorylated VEGFR-2 expression increased significantly after singleand repeated bevacizumab treatments compared with the control. The 1.0 mg/m L bevacizumab induced significantly higher expressions of VEGFR-2 than the 2.5 mg/m L in single and repeated treatment groups.CONCLUSION： Bevacizumab treatment of HUVECs elevated VEGFR expression in both single and repeated treatments, indicating a mechanism for the reduced efficacy of anti-VEGF therapy in ocular neovascular disorders.