ObjectiveTo observe the expression of connective tissue growth factor (CTGF) in injured model of retinal pigment epithelial (RPE) cells and the promoting effect of CTGF on migration of RPE cells.MethodsCultured monolayer-confluent human RPE cells were scraped with a trephine and a cotton stick, and set up the injured model of RPE cells with round scraped area. Immunohistochemistry and in situ hybridization(ISH) were used to detect the expression of CTGF protein and mRNA in injured RPE cells at distinct time points after injury. The number of RPE cells migrated to injured area was measured and the effect of CTGF on migration of RPE cells and the effect of dexamethasone (DEX) on the promoting process of CTGF were observed.ResultsThe results of immunohstochemistry and ISH indicated the weak positive expression of CTGF in RPE cells at the edge of scrape 6 hours after injury, and the positive expression increased gradually as time goes by after the injury. Strong positive expression of CTGF in RPE cells at the edge of scrape was found 24 and 48 hours after injury. Rebuilt human CTGF stimulated migration of RPE cells in a dose-depended manner, and DEX significantly inhabited the migration.ConclusionCTGF involves in the procedure of repair of injury of RPE cells, which may play an important role in the pathogenesis of intraocular proliferative diseases such as proliferative vitreoretinaopathy.(Chin J Ocul Fundus Dis, 2005,21:306-309)
Objective To evaluate the effect of vascular endothelial growth factor (VEGF) on tumor angiogenesis, and its usage in tumor therapy.Methods The recent literatures about VEGF and angiogenesis were reviewed and analyzed. The advances of VEGF study were summarized. The effects of anti-angiogenesis in tumor biological therapy were introduced.Results Angiogenesis had been identified as an important factor for promoting tumor growth. VEGF was a basic and pivotal factor in tumor angiogenesis. The anti-angiogenesis treatments aimed at VEGF, including the applications of VEGF inhibitor and gene therapy of adenovirus medium, had got great progress. Conclusion VEGF is a leading factor of tumor angiogenesis, the anti-angiogenesis therapy aimed at VEGF has probably provided a new chance to malignant tumor treatment.
Objective To observe the expression of p53, bcl-2 genes, vascular endothelial cell growth factor（VEGF）, basic fibroblast growth factor（bFGF）, insulin-like growth factor-I （IGF-I）, and the receptors of these factors of retinal vascular endothelial cells (VECs) of 1- to 20-week diabetic rats, and the relationship between the expressions and cell cycle arrest.Methods Retinal sections of diabetic rats induced by alloxan were immunohistochemically stained and observed by light microscopy (LM) and electron microscopy (EM). Dot blotting and Western blotting were used to determine the expression of mRNA, proteins of p53 and bcl-2. Results Under LM, immunohistochemical positive expression of p53 and bcl-2 were found on the vessels of ganglion cell layer and inner nuclear layer of retinae of 8- to 20-week diabetic rats; under EM, these substances were observed depositing in VECs. The retinal VECs also expressed VEGF, bFGF, IGF-I and their receptors. There was no positive expression of other cell types in these retinae, all cell types of retinae in control group, or all cells of retinae of diabetic rats with the course of disease of 1 to 6 weeks. The result of dot blotting revealed that retinal tissue of 20-week diabetic rat expressed p53 and bcl-2 mRNA, and the result of Western blotting revealed that they also expressed p53 and bcl-2 proteins. But retinal tissues of control group did not. Positive expression of bax was not found in the retinae in control group or 1- to 20-week diabetic rats. Conclusion p53, bcl-2 may introduce cell cycle arrest of VECs of retinae in 8- to 20-week diabetic rats. High glucose might stimulate the expression of VEGF, bFGF, IGF-I and their receptors, and the growth factors may keep VECs surviving by self-secretion. (Chin J Ocul Fundus Dis，2003，19：29-33)
ObjectiveTo observe the expression of Rap1, guanosine triphosphate-Rap1 (GTP-Rap1), vascular endothelial growth factor (VEGF) and β-catenin in experimental choroidal neovascularization (CNV).MethodsForty-two brown Norwegian rats were randomly divided into a blank control group (7 rats) and a model group (35 rats). Both eyes were enrolled. The CNV model was established by holmium ion laser photocoagulation in the model group. At 3, 7, 14, 21, and 28 days after photocoagulation, fluorescein fundus angiography (FFA) and choroidal vascular smear were performed to observe the degree of fluorescein leakage and CNV area in rats; Western blot and real-time quantitative polymerase chain reaction (RT-PCR) were used to detect the expression of Rap1, GTP-Rap1, VEGF, β-catenin and mRNA in CNV.ResultsThe results of FFA examination showed that a large disc-shaped fluorescein leaked in the photo-condensation spot 14 days after photocoagulation. Laser confocal microscopy showed that compared with 7 days after photocoagulation, CNV area increased at 14, 21, 28 days after photocoagulation, and the difference were statistically significant (t=3.725, 5.532, 3.605;P＜0.05). Western blot showed that there was no significant difference in the relative expression of Rap1 protein in CNV at different time points after photocoagulation between the two groups (P=0.156). Compared with the blank control group, the relative expression of GTP-Rap1 protein was significantly decreased, the relative expression of VEGF and β-catenin protein were significantly increased in the model group (P=0.000). The results of RT-PCR showed that there was no significant difference in the relative expression of Rap1 mRNA at different time points after photocoagulation between the two groups (P=0.645), but there were significant difference in the relative expression of β-catenin mRNA (P=0.000). At 7, 14, 21 and 28 days after photocoagulation, there were significant difference in the relative expression of GTP-Rap1 and VEGF mRNA between the two groups (P=0.000).ConclusionsThe expression of GTP-Rap1 in experimental CNV is significantly lower than that in normal rats.
Objective To construct green fluorescent protein (GFP)/Akt fusion gene vector for observing the expression and localization of GFP/Akt in rats bone marrow-derived mesenchymal stem cells （MSCs）. Stem cell factor （SCF） effected expression of c-kit, Akt and VEGF mRNA and protein in MSCs transfected by pEGFP-C1/Akt through PI3-Akt pathway.Methods Akt recombined GFP vector by restriction enzymes, MSCs was transfeced by GFP/Akt and GFP through cationic liposomes, and then veritied by restriction endonuclease assay and sequence analysis. Transfection and localization of GFP were evaluated by fluorescene microscopy. The expressions of c-kit, Akt and VEGF mRNA and protein were examined by RT-PCR and Western blot after MSCs transfected by pEGFP-C1 and pEGFP-C1/Akt. SCF effected the expression of c-kit, Akt and VEGF mRNA and protein after MSCs transfected by pEGFP-C1 and pEGFP-C1/Akt. Results Restriction endonuclease assay and sequence analysis verified that thesuccessfulconstructionoftherecombinantvectorpEGFP-C1/AktandefficienthighexpressionofpEGFP-C1/Akt fusion protein in the MSCs of rats. Under fluorescent microscence, green flurescence was seen homogeneously distributed in the entire cell of the cells transfected by the recombinant vector pEGFP-C1, and diffusely in the cytoplasm of the cells transfected by the recombinant vector pEGFP-C1/Akt. The expression of Akt and VEGF mRNA and protein were significantly higher in MSCs transfected by pEGFP-C1/Akt (plt;0.05). The expression of c-kit, Akt and VEGF mRNA and protein were significantly higher in experiment group (SCF+pEGFP-C1/Akt) and control group (SCF+pEGFP-C1), plt;0.05. In experiment group， SCF stimulation enhanced expression of Akt and VEGF mRNA and protein (plt;0.01). Conclusion GFP/Akt fusion gene vector is successfully construted and the fusion protein expressed in the MSCs of rats induces the expression of Akt and VEGF mRNA and protein. SCF stimulation enhanced expression of c-kit, Akt and VEGF mRNA and protein through PI3/Akt pathway.
Objective To evaluate the effect of vascular endothelial cell growth factor (VEGF) antisense oligodeoxynucleotides (ASODNs) on the expression of VEGF in rats with oxygen-induced retinopathy. Methods Thirty newborn Sprague-Dawley (SD) rats were randomly divided into 3 groups:normal control group, disposal group and non-disposed group, The animal models with oxygen-induced proliferative retinopathy were established by raising the rats in hyperoxic environment. Retrobulbar injection was performed with VEGF ASODNs or normal saline on the rats in 3 groups respectively. The intraocular tissues (all the tissues except the cornea, sclera, and lens) and serum were collected, and the expressions of VEGF were determined by using competitive enzyme immunoassay.Results The expressions of VEGF in intraocular tissues of rats in disposal group were significantly lower than those in non-disposed group (P＜0.05), and there was no statistical difference between the disposal and normal control group (P＞0.05). There was no significant difference of the expressions of VEGF in serum of rats between the disposal and non-disposed group (P＞0.05), which were both lower than those in the normal control group (P＜0.05). Conclusion VEGF ASODNs could significantly inhibit the expression of VEGF in intraocular tissues. (Chin J Ocul Fundus Dis，2003，19：172-174)
Objective To analyze the diagnostic value of shear wave elastography (SWE) combined with vascular endothelial growth factor B (VEGF-B) and hemoglobin A1c (HbA1c) in early diabetic peripheral neuropathy (DPN). Methods A total of 100 patients with type 2 diabetes mellitus (T2DM) admitted to Mianyang Central Hospital between October 2020 and October 2023 were selected and divided into a T2DM with DPN group (n=31) and a T2DM without DPN group (n=69) based on the presence or absence of DPN. Additionally, 50 healthy individuals from the same hospital’s health examination center were included as a healthy control group. The basic clinical characteristics, mean elasticity (Emean) values of the left and right median and tibial nerves, serum VEGF-B, and HbA1c levels were compared among the three groups. The diagnostic efficacy of SWE, VEGF-B, and HbA1c for DPN was evaluated using receiver operating characteristic (ROC) curves, and Pearson correlation analysis was performed to assess the relationships between median/tibial nerve Emean and VEGF-B/HbA1c. Results The Emean values of the left and right median nerves, Emean values of the left and right tibial nerves, serum VEGF-B, and HbA1c levels in the T2DM with DPN group were significantly higher than those in the T2DM without DPN group and the healthy control group (P<0.05). The Emean values of the left and right median and tibial nerves, Emean values of the left and right tibial nerves, and HbA1c level in the T2DM without DPN group were significantly higher than those in the healthy control group (P<0.05), while no significant difference was observed in serum VEGF-B level between the T2DM without DPN group and the healthy control group (P>0.05). The area under the ROC curve for the combined diagnosis of DPN using SWE, VEGF-B, and HbA1c was 0.859 [95% confidence interval (0.828, 0.955)]. The sensitivity of the combined diagnosis (93.72%) was significantly higher than that of individual diagnoses (78.82%, 75.39%, and 71.05%, respectively; P<0.05), while the specificity (88.64%) showed no significant difference compared to individual diagnoses (80.18%, 78.96%, and 82.88%, respectively; P>0.05). Positive correlations were observed between median/tibial nerve Emean and VEGF-B/HbA1c levels (r=0.428, 0.395, 0.416, and 0.416, respectively; P<0.05). Conclusions Elevated median/tibial nerve Emean, serum VEGF-B, and HbA1c levels are closely associated with DPN. The combination of SWE, VEGF-B, and HbA1c improves diagnostic sensitivity for DPN, demonstrating significant clinical value.
Esophageal cancer is one of the common malignant tumors with high incidence and poor prognosis. Angiogenesis-related pathways play an important role in the occurrence and development of esophageal cancer. Vascular endothelial growth factor (VEGF) is the main mediator of angiogenesis. In addition to promoting angiogenesis and maintaining the survival of neovascularization, VEGF can also directly act on esophageal cancer cells and promote the occurrence and development of tumors. This article reviews the biology of VEGF and its effect on blood vessels, the expression of VEGF in esophageal cancer cells and its influencing factors, the role of VEGF in esophageal cancer cells, the immunomodulatory activity of VEGF and the clinical study of VEGF inhibitors. The purpose of this study is to provide a basis for more rational use of VEGF inhibitors in the treatment of esophageal cancer.
Objective To determine the association between the geneti c polymorp hisms of vascular endothelial growth factor (VEGF) gene and the prognosis for retinopathy of prematurity (ROP) in Chinese. Methods Twenty infants with threshold ROP who had undergone retinal photocoagulation were in the treated group and 20 infants with self-regressed ROP without any treatment were in the control grou p . In the two groups, all the infants had oxygen-breathing history and the sex a n d gestational age were all suitable to be compared, except birth weight. Polymer ase chains reaction-restriction fragment length polymorphism was used to determine the frequencies of VEGF genes in the two groups. Results The frequencies of +405C allele were higher in the treated group than those in the control group (P＜0.05). The frequencies of the VEGF-460T/C and +936C/T ploymorphisms were similar in both groups (P＞0.05). Conclusions The +4 05C/G ge netic polymorphisms of VEGF may correlate to the prognosis of ROP. The carriers of +405CC allele are more susceptible to ROP.
ObjectiveTo investigate the effects of transforming growth factor-β (TGF-β) in choroidal neovascularization (CNV) induced by laser in mice. Methods Eighty male C57BL/6J mice at the age of 6-8 weeks old were randomly divided into the normal control, photocoagulation model, photocoagulation with phosphate buffered saline (PBS control group) and photocoagulation with TGF-β receptor inhibitor groups (TGF-β receptor inhibitor group), twenty mice of each group. Fundus argon laser photocoagulation was performed in the photocoagulation model group, PBS control group and TGF-β receptor inhibitor group to induce CNV. One week, two, three and four weeks after the laser procedure, fundus fluorescein angiography (FFA) was carried out in the normal control or photocoagulation model groups to observe CNV formation dynamically. Western blot was used to analyze the expressions of TGF-β in the retina from the mice of normal control or photocoagulation model groups, and VEGF or TNF-α in the retina of normal control, PBS control or TGF-β receptor inhibitor groups. The CNV areas of each group were evaluated by using fluorescein stain on retinal pigment epithelium (RPE)/choroid flat mounts after two weeks of photocoagulation. ResultsThe FFA results showed the retinal vessels centered on the optic disc and arranged radially, while the choroidal vascular present network distribution in the normal control mice. Significant leakage of fluorescein showed discoid strong fluorophore in photocoagulation sites of retina at one week after photocoagulation. The quantitative analysis results of Western blot demonstrated that the TGF-β protein expression levels in retina of photocoagulation model mice gradually increased with time passing. The protein expression levels of TGF-β were significant differences in the photocoagulation model group comparing with the normal control group (F=13.042, P < 0.05). The protein expression levels of TNF-α (F=14.721, 17.509) and VEGF (F=18.890, 11.251) increased significantly in retina of PBS control or TGF-β receptor inhibitor groups when compared with that of normal control group at one week, two, three and four weeks after photocoagulation, and the differences were both statistically significant (P < 0.05). Compared with PBS control group, the protein levels of TNF-α and VEGF in retina from TGF-β receptor inhibitor group were significantly reduced, the differences was statistically significant (F=21.321, 16.160, P < 0.05). Two weeks after laser photocoagulation, a distinct reduction in CNV lesion size in the TGF-β receptor inhibitor group mice when compared to PBS or normal control groups, the differences was statically significant (F=4.482, P < 0.05). ConclusionTGF-β may promote CNV formation by up-regulating both TNF-α and VEGF protein expressions, the application of its specific inhibitor is able to reduce CNV progression.