Objective To study the time effect of the gene expression of recombinant adeno-associated virus (rAAV) vector co-expressing human vascular endothel ial growth factor 165 (hVEGF165) and human bone morphogenetic protein 7 (hBMP-7) genes so as to lay a theoretical foundation for gene therapy of osteonecrosis. Methods The best multipl icity of infection (MOI) of BMSCs transfected with rAAV was detected by fluorescent cell counting. The 3rd generation rabbit bone mesenchymal stem cells (BMSCs) were transfected with rAAV-hVEGF165-internal ribosome entry site (IRES)-hBMP-7 (experimental group) and green fluorescent protein (GFP) labeled rAAV-IRES-GFP (control group), respectively. The expression of GFP was observed by inverted fluorescent microscope. The expressions of hVEGF165 and hBMP-7 were assessed by RT-PCR assay and Western blot assay in vitro. The transfected cells in 2 groups were prepared into suspension with 5 × 106 cells/mL, and injected into the rabbit thigh muscles of experimental group 1 (n=9) and control group 1 (n=9), respectively. The muscle injected with rAAV-IRES-GFP was sl iced by frozen section method and the expression of GFP protein was observed by inverted fluorescent microscope. The expressions of hVEGF165 and hBMP-7 were assessed by Western blot assay and ELISA assay in vivo. Results The best MOI of BMSCs transfected with rAAV was 5 × 104 v.g/cell. In vitro, the expressions of GFP, hVEGF165, and hBMP-7 genes started at 1 day after transfection, the expressions obviously increased at 14 days after transfection, and the expression maintained the b level at 28 days after transfection. In vivo, the expressions of GFP, hVEGF165, and hBMP-7 genes could be detected at 2 weeks after injection, and b expressions were shown at 6 to 8 weeks after injection. The values of hVEGF165 and hBMP-7 were (248.67 ± 75.58) pg/mL and (4.80 ± 0.61) ng/mL respectively in experimental group 1, and were (32.28 ± 8.42) pg/mL and (0.64 ± 0.42) ng/mL respectively in control group 1; showing significant differences between 2 groups (P lt; 0.05). Conclusion The rAAV-hVEGF165-IRES-hBMP-7 has efficient gene expression ability.
Objective To investigate whether human amniotic mesenchymal stem cells (hAMSCs) have the characteristics of mesenchymal stem cells (MSCs) and the differentiation capacity into ligament fibroblastsin vitro. Methods The hAMSCs were separated through trypsin and collagenase digestion from placenta, the phenotypic characteristics of hAMSCs were detected by flow cytometry, the cytokeratin-19 (CK-19) and vimentin expression of hAMSCs were tested through immunofluorescence staining. The hAMSCs at the 3rd passage were cultured with L-DMEM/F12 medium containing transforming growth factor β1 (TGF-β1) and vascular endothelial growth factor (VEGF) as the experimental group and with single L-DMEM/F12 medium as the control group. The morphology of hAMSCs was observed by inverted phase contrast microscope; the cellular activities and ability of proliferation were examined by cell counting kit-8 (CCK-8) method; the ligament fibroblasts related protein expressions including collagen type I, collagen type III, Fibronectin, and Tenascin-C were detected by immunofluorescence staining; specific mRNA expressions of ligament fibroblasts and angiogenesis including collagen type I, collagen type III, Fibronectin, α-smooth muscle actin (α-SMA), and VEGF were measured by real-time fluorescence quantitative PCR. Results The hAMSCs presented monolayer and adherent growth under inverted phase contrast microscope; the flow cytometry results demonstrated that hAMSCs expressed the MSCs phenotypes; the immunofluorescence staining results indicated the hAMSCs had high expression of the vimentin and low expression of CK-19; the hAMSCs possessed the differentiation ability into the osteoblasts, chondroblasts, and lipoblasts. The CCK-8 results displayed that cells reached the peak of growth curve at 7 days in each group, and the proliferation ability in the experimental group was significantly higher than that in the control group at 7 days (P<0.05). The immunofluorescence staining results showed that the expressions of collagen type I, collagen type III, Fibronectin, and Tenascin-C in the experimental group were significantly higher than those in the control group at 5, 10, and15 days after culture (P<0.05). The real-time fluorescence quantitative PCR results revealed that the mRNA relative expressions had an increasing tendency at varying degrees with time in the experimental group (P<0.05). The relative mRNA expressions of collagen type I, collagen type III, Fibronectin, α-SMA, and VEGF in the experimental group were significantly higher than those in the control group at the other time points (P<0.05), but no significant difference was found in the relative mRNA expressions of collagen type I, collagen type III, and VEGF between 2 groups at 5 days (P>0.05). Conclusion The hAMSCs possesses the characteristics of MSCs and good proliferation ability which could be chosen as seed cell source in tissue engineering. The expressions of ligament fibroblasts and angiogenesis related genes could be up-regulated, after inductionin vitro, and the synthesis of ligament fibroblasts related proteins could be strengthened. In addition, the application of TGF-β1 and VEGF could be used as growth factors sources in constructing tissue engineered ligament.
Objective To systematically evaluate expression of vascular endothelial growth factor (VEGF) protein in triple negative breast cancer (TNBC) and analyze its correlation between positive expression of VEGF protein and clinicopathologic features of patient with TNBC. Methods The published literatures relevant VEGF protein expression in TNBC and its relation to clinicopathologic features of patient with TNBC in China were retrieved by means of CNKI, Wanfang, VIP, China Biomedical, Chaoxing Medalink, PubMed databases, and other search tools. The literatures were independently filtered, extracted, and assessed by two reviewers according to the inclusion criteria and exclusion criteria. The meta-analysis was conducted by using RevMan 5.3 software. Results A total of 11 literatures were included and involved 1 838 patients (750 patients in the TNBC group and 1 088 patients in the non-TNBC group). The results of meta-nalysis showed that the positive expression of VEGF protein in the TNBC group was significantly higher than that in the non-TNBC group 〔OR=2.64, 95%CI (2.14, 3.26), P<0.000 01〕 , which was significantly increased in the TNBC patients with positive lymph node or stage Ⅲ–Ⅳ as compared with the negative lymph node or stage Ⅰ–Ⅱ 〔OR=0.30, 95% CI (0.14, 0.46), P=0.000 2; OR=0.43, 95% CI (0.29, 0.62), P<0.000 01〕 . However, the positive expression of VEGF protein was no associated with the age of patients with TNBC or tumor size (P>0.05). Conclusions VEGF highly expresses in TNBC and it is expected to be a new therapeutic target. Positive expression of VEGF protein is related to positive lymph node and late TNM stage, and it might be associated with prognosis of patient with TNBC.
Objective To explore the influence on the expressions of vascular endothelial growth factor (VEGF) gene and matrix metalloproteinase-2 (MMP-2) gene in hepatocellular carcinoma of SMMC-7721 cells with RNA interference (RNAi) silencing the expression of hypoxia inducible factor-1α (HIF-1α) gene. Methods Firstly, constructed short hairpin RNA (shRNA) targeting for HIF-1α gene, and then transfected it to SMMC-7721 cells after combining with plasmid. The SMMC-7721 cells were divided into three groups, silencing group, negative control group, and blank control group, which were transfected with HIF-1α-shRNA-pGenesil-1 recombinant vector, shRNA-HK-pGenesil-1 recombinant vector, and pGenesil-1 vector respectively. Transfection cells were screened by the concentration of 500 μg/mL G418, and then positive and negative cell clones with transfection recombination carrier were obtained. Detected the expressions of HIF-1α mRNA, VEGF mRNA, and MMP-2 mRNA in the 3 groups with real time PCR (RT-PCR) technology, under the condition of hypoxic training 6 h, 12 h, and 24 h, as well as conventional oxygen training. Results There was no expression of HIF-1α mRNA at conventional oxygen condition in the 3 groups, and there was no significant difference in expressions of VEGF mRNA and MMP-2 mRNA among the 3 groups (P>0.05) at the condition of conventional oxygen training. The expressions of HIF-1α mRNA, VEGF mRNA, and MMP-2 mRNA in the silencing group, compared with the the negative control group and the blank control group, were obviously decreased (P<0.05) under the condition of hypoxic training (6, 12, and 24 h), while there was no significant difference between the negative control group and the blank control group at each time point (P>0.05), but the expressions of HIF-1α mRNA, VEGF mRNA, and MMP-2 mRNA in the 3 groups under every condition of hypoxic training were all higher than those of conventional oxygen condition (P<0.05). Under the condition of hypoxic training, the expressions of HIF-1α mRNA, VEGF mRNA, and MMP-2 mRNA in the 3 groups decreased over time, and there was significant difference between any 2 time points in each group (P<0.05). Conclusion RNAi technique can effectively silence the expression of HIF-1α mRNA of SMMC-7721 cells, and then silence the expressions of VEGF and MMP-2 mRNA, to inhibit the invasion and metastasis of hepatocellular carcinoma.
ObjectiveTo explore the effect of vascular endothelial growth factor 165 (VEGF165)-loaded porous poly (ε-caprolactone) (PCL) scaffolds on the osteogenic differentiation of adipose-derived stem cells (ADSCs).MethodsThe VEGF165-loaded porous PCL scaffolds (written, Sf-g/VEGF) were fabricated through a combination of solvent casting/salt leaching and a thermal-induced phase separation technique and then observed under scanning electron microscope (SEM). The release kinetics was determined by ELISA kit. The ADSCs were isolated from inguinal fat pads of 15 Sprague Dawley rats and cultured. The passage 3-4 ADSCs were seeded into the scaffolds, and then cultured in vitro for 7 days. The passage 3-4 ADSCs were seeded into the porous PCL scaffolds (written, Sf-g) as control. The alizarin red S (ARS) staining, ARS activity assay, and real-time quantitative PCR (RT-PCR) were performed to measure the osteogenic differentiation of ADSCs in vitro. Six Sprague Dawley rats were recruited to prepare the bilateral calvarial bone defects models (n=12). The 12 calvarial bone defects were randomly divided into 3 group (n=4). The defects of negative control group were not treated; the defects of Sf-g group and Sf-g/VEGF group were repaired with ADSCs-Sf-g scaffold complex and ADSCs-Sf-g scaffold complex, respectively. At 8 weeks after transplantation, the Micro-CT and HE staining were conducted to evaluate the osteogenic effects in vivo.ResultsThe morphology of the Sf-g/VEGF scaffolds were porous and well-connected, and the cumulative release rate was approximately 80% in 120 hours. The ARS staining showed that the ARS activity of Sf-g/VEGF group were stronger than that of Sf-g group (t=10.761, P=0.000). The mRNA expressions of osteogenic specific markers [special AT-rich sequence protein 2 (Satb2), alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN)] were significantly higher in Sf-g/VEGF group than in Sf-g group (P<0.05). The results of Micro-CT and HE staining also confirmed the promotion effect of Sf-g/VEGF scaffolds. All defects of 2 groups were partially repaired by new bone tissue, especially in Sf-g/VEGF group. The volume and area of new bone tissue were significantly higher in Sf-g/VEGF group than in Sf-g group (P<0.05).ConclusionThe VEGF165-loaded scaffolds can significantly improve the osteogenic differentiation of ADSCs both in vitro and in vivo.
ObjectiveTo investigate the mechanism of G protein coupled receptor kinase interacting protein 1 (GIT1) affecting angiogenesis by comparing the differentiation of bone marrow mesenchymal stem cells (BMSCs) differentiated into endothelial cells between GIT1 wild type mice and GIT1 gene knockout mice.MethodsMale and female GIT1 heterozygous mice were paired breeding, and the genotypic identification of newborn mice were detected by PCR. The 2nd generation BMSCs isolated from GIT1 wild type mice or GIT1 gene knockout mice were divided into 4 groups, including wild type control group (group A), wild type experimental group (group A1), GIT1 knockout control group (group B), and GIT1 knockout experimental group (group B1). The cells of groups A1 and B1 were cultured with the endothelial induction medium and the cells of groups A and B with normal cluture medium. The expressions of vascular endothelial growth factor receptor 2 (VEGFR-2), VEGFR-3, and phospho-VEGFR-2 (pVEGFR-2), and pVEGFR-3 proteins were detected by Western blot. The endothelial cell markers [von Willebrand factor (vWF), platelet-endothelial cell adhesion molecule 1 (PECAM-1), and vascular endothelial cadherin (VE-Cadherin)] were detected by flow cytometry. The 2nd generation BMSCs of GIT1 wild type mice were divided into 4 groups according to the different culture media: group Ⅰ, primary cell culture medium; group Ⅱ, cell culture medium containing SAR131675 (VEGFR-3 blocker); group Ⅲ, endothelial induction medium; group Ⅳ, endothelial induction medium containing SAR131675. The endothelial cell markers (vWF, PECAM-1, and VE-Cadherin) in 4 groups were also detected by flow cytometry.ResultsWestern blot results showed that there was no obviously difference in protein expressions of VEGFR-2 and pVEGFR-2 between groups; and the expressions of VEGFR-3 and pVEGFR-3 proteins in group A1 were obviously higher than those in groups A, B, and B1. The flow cytometry results showed that the expressions of vWF, PECAM-1, and VE-Cadherin were significantly higher in group A1 than in groups A, B, and B1 (P<0.05), and in group B1 than in groups A and B (P<0.05); but no significant difference was found between groups A and B (P>0.05). In the VEGFR-3 blocked experiment, the flow cytometry results showed that the expressions of vWF, PECAM-1, and VE-Cadherin were significantly higher in group Ⅲ than in groupsⅠ, Ⅱ, and Ⅳ, and in group Ⅳ than in groups Ⅰ and Ⅱ (P<0.05); but no significant difference was found between groups Ⅰ and Ⅱ (P>0.05).ConclusionGIT1 mediates BMSCs of mice differentiation into endothelial cells via VEGFR-3, thereby affecting the angiogenesis.
ObjectiveTo observe the effect of vascular endothelial growth factor/polylactide-polyethyleneglycol-polylactic acid copolymer/basic fibroblast growth factor (VEGF/PELA/bFGF) mixed microcapsules in promoting the angiogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) in vitro. MethodsThe BMSCs were isolated by the method of whole bone marrow adherent, and sub-cultured. The passage 3 BMSCs were identified by Wright-Giemsa staining and flow cytometry, and used for subsequent experiments. VEGF/PELA/bFGF (group A), PELA/bFGF (group B), VEGF/PELA (group C), and PELA (group D) microcapsules were prepared. The biodegradable ability and cytotoxicity of PELA microcapsule were determined, and the slow-released ability of VEGF/PELA/bFGF mixed microcapsules was measured. The passage 3 BMSCs were co-cultured with the extracts of groups A, B, C, and D, separately. At 1, 3, 7, 14, and 20 days after being cultured, the morphological changes of induced BMSCs were recorded. At 21 days, the induced BMSCs were tested for DiI-labeled acetylated low density lipoprotein (Dil-ac-LDL) and FITC-labeled ulex europaeus agglutinin I (FITC-UEA-I) uptake ability. The tube-forming ability of the induced cells on Matrigel was also verified. The differences of the vascularize indexes in nodes, master junctions, master segments, and tot.master segments length in 4 groups were summarized and analyzed. ResultsThe isolated and cultured cells were identified as BMSCs. The degradation time of PELA was more than 20 days. There was no significant effect on cell viability under co-culture conditions. At 20 days, the cumulative release of VEGF in the mixed microcapsules exceeded 95%, and the quantity of bFGF exceeded 80%. The morphology of cells in groups A, B, and C were changed. The cells in groups A and B showed the typical change of cobble-stone morphology. The numbers of double fluorescent labeled cells observed by fluorescence microscope were the most in group A, and decreases from group B and group C, with the lowest in group D. The cells in groups A and B formed a grid-like structure on Matrigel. Quantitative analysis showed that the differences in the number of nodes, master junctions, master segments, and tot.master segments length between groups A, B and groups C, D were significant (P<0.05). The number of nodes and the tot.master segments length of group A were more than those of group B (P<0.05). There was no significant differences in the number of master junctions and master segments between group A and group B (P>0.05). ConclusionVEGF/PELA/bFGF mixed microcapsules have significantly ability to promote the angiogenic differentiation of rat BMSCs in vitro.
ObjectiveTo investigate the effect of all-trans retinoic acid (ATRA) and vascular endothelial growth factor (VEGF) on the osteogenic differentiation of mouse embryonic fibroblasts (MEFs).MethodsThe fetal mice in the uterus of NIH pregnant mice (pregnancy 12-15 days) were collected, and the heads and hearts etc. were removed. Then MEFs were separated from the rest tissues of the fetal mice and cultured by trypsin digestion and adherent culture. HEK-293 cells were used to obtain recombinant adenovirus-red fluorescent protein (Ad-RFP) and Ad-VEGF by repeatedly freezing and thawing. Alkaline phosphatase (ALP) staining and quantitative detection were used to detect the changes of ALP activity in MEFs applied with ATRA or VEGF alone or combined use of ATRA and VEGF on the 3rd and 5th days. The cultured 3rd to 4th generation MEFs were divided into groups A, B, C, and D, and were cultured with DMSO plus Ad-RFP, ATRA, Ad-VEGF, ATRA plus Ad-VEGF, respectively. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the mRNA expressions of osteogenic markers including ALP, collagen type Ⅰ, osteopontin (OPN), osteocalcin (OCN), and angiogenic markers including VEGF, angiopoietin 1 (ANGPT1), and endomucin (EMCN) on the 3rd and 7th days. Immunohistochemical staining was used to detect the protein expressions of OPN and VEGF on the 3rd, 5th, and 7th days in each group. Alizarin red staining was used to detect calcium salt deposition levels in each group at 14 and 21 days after osteogenic induction. Fifteen athymic female nude mice aged 4 to 6 weeks were randomly divided into 3 groups and 5 mice in each group. Then MEFs treated with ATRA, Ad-VEGF, and ATRA plus Ad-VEGF were injected subcutaneously into the dorsal and ventral sides, respectively. X-ray observation, gross observation, and histological staining (Masson, HE, and Safranin O-fast green stainings) were performed at 5 weeks after implantation to observe the ectopic bone formation in nude mice in each group.ResultsMEFs were successfully isolated and cultured. The acquired Ad-RFP and Ad-VEGF were successfully transfected into MEFs with approximately 50% and 20% transfection rates. ALP activity tests showed that ATRA or Ad-VEGF could enhance ALP activity in MEFs (P<0.05), and ATRA had a stronger effect than Ad-VEGF; and the combined use of ATRA and Ad-VEGF significantly enhanced the ALP activity in MEFs (P<0.05). qRT-PCR test showed that the combined use of ATRA and Ad-VEGF also increased the relative mRNA expressions of early-stage osteogenesis-related markers ALP, OPN, and collagen type I (P<0.05); the relative mRNA expressions of angiogenesis-related markers VEGF, EMCN, and ANGPT1 increased at 7 days (P<0.05). Immunohistochemical staining showed that ATRA combined with Ad-VEGF not only enhanced OPN protein expression, but also increased VEGF protein expression on 7th day. Alizarin red staining showed that the application of ATRA or Ad-VEGF induced weak calcium salt deposition, and the combined use of ATRA and Ad-VEGF significantly enhanced the effect of calcium salt deposition in MEFs. The results of implantation experiments in nude mice showed that X-ray films observation revealed obvious bone mass in the ATRA plus Ad-VEGF group, and the bone was larger than that in other groups. Histological staining showed a large amount of collagen and mature bone trabeculae, bone matrix formation, and gray-green collagen bone tissue, indicating that the combined use of ATRA and Ad-VEGF significantly enhanced the osteogenic effect of MEFs in vivo.ConclusionThe combined use of ATRA and VEGF can induce the osteogenic differentiation of MEFs.
ObjectiveTo detect expressions of E-cadherin (E-cad) and vascular endothelial growth factor (VEGF) in gastrointestinal stromal tumor (GIST) tissues and analyze their relationships with clinicopathologic features of patients with GIST.MethodsForty paraffin-embeded specimens of surgical resected GIST from January 2015 to March 2018 in the Pathology Department of Yuhuangding Hospital Affilicated to Qingdao University were retrieved. The expressions of E-cad and VEGF proteins were detected by the immunohistochemical method.ResultsThe positive expression rates of E-cad and VEGF proteins in the GIST tissues were 10.0% (4/40) and 50.0% (20/40), respectively. The positive expression rates of E-cad and VEGF proteins were associated with the tumor diameter, mitotic counts, and risk classification (P<0.05). The positive expression rate of the E-cad was negatively related to that of the VEGF in the GIST tissues (rs=–0.55, P=0.001).ConclusionFrom results of this study, VEGF and E-cad might be related with malignancy of GIST, which might be potential facators in predicting prognosis of GIST.
ObjectiveTo investigate the significance of the expression of vascular endothelial growth factor (VEGF) in portal vein thrombosis after operation in patients with portal hypertension.MethodsThe serum of 146 patients with portal hypertension treated in Dongfeng Hospital Affiliated to Hubei Medicial College from January 2014 to December 2018 and the surgically removed splenic vein and spleen specimens were collected. The serum VEGF level was determined by enzyme-linked immunosorbent assay, and the expressions of VEGF in splenic vein and spleen tissues were detected by immunohistochemistry. According to whether portal vein thrombosis was formed after operation, the patients were divided into thrombosis group and non-thrombosis group, and the differences between the groups were compared.ResultsThe serum VEGF level in the thrombosis group was significantly higher than that in the non-thrombosis group (P<0.05). In splenic vein wall and spleen tissues, VEGF staining indexes in the thrombosis group were significantly higher than those in the non-thrombosis group (P<0.05).ConclusionsPostoperative portal vein thrombosis in patients with portal hypertension may be related to the serum VEGF level. The high expressions of VEGF in splenic vein wall and spleen suggest that VEGF may participate in the formation process of portal vein thrombosis.