【Abstract】Objective To introduce the current studies of the role of vascular endothelial growth factorC (VEGFC) and VEGFD in lymphangiogenesis and lymph node metastasis of gastrointestinal neoplasma. Methods The related literatures in recent 5 years were reviewed. Results The growth factors VEGFC and VEGFD enhance lymphangiogenic metastasis of gastrointestinal neoplasma with the property of angiogenesis and lymphangiogenesis. In gastric adenocarcinoma, VEGFC mRNA and tissue protein expression correlate with lymphatic invasion, lymph node metastasis, venous invasion and reduced 5year survival rates. The role of VEGFC in esophageal squamous cancer and colorectal cancer and VEGFD in colorectal cancer is not certain, with conflicting reports in the published literatures.Conclusion The VEGFC, VEGFD/VEGFR3 signal pathway may become the ideal target for inhibition of tumor proliferation and metastases, antilymphangiogenesis therapy may be a novel potential strategy in tumor biological therapy.
Objective To observe the effects of immunologic cytokines or anti-angiogenesis gene transfer mediated by electroporation for choroidal melanoma cells.Methods The human embryo kidney cells and malignant choroidal melanoma cells were transfected with plasmids pNGVL-mIL2, pNGVL-mIL12, pCI-sFLK-1, pCR3.1-antiVEGF121,pCI-ExTek. Then the expression of mIL2, mIL12, sFLK-1, VEGF and ExTek were detected by enzymelinked immunosorbentassay (ELISA) and Western blot. Nude mice models of malignant choroidal melanoma were established and they were divided into four groups randomly. Each group was treated with 30 mu;l of 0.9% NaCl, 30 mu;g pNGVL, 30 mu;g antiVEGF121+sFLK-1+ExTek and 30 mu;g mIL2+mIL12 respectively by electroporation. Seven，14, 21, 28, 35 and 42 days after treatment, the tumor volumes were measured to calculate the tumor inhibition rate. Results ELISA and Western blot showed that mIL2，mIL12，sFLK-1 and ExTek were expressed after electroporation，VEGF expression was decreased remarkably. After treatment，the tumors of mIL2+mIL12 group were greatly inhibited with a tumor inhibition rate of 97.33%，while the tumors of antiVEGF121+sFLK-1+ExTek and pNGVL group were partially inhibited with tumor inhibition rates of 53.33% and 36.33% respectively.Conclusions Immunologic cytokines transfer mediated by electroporation can inhibit the growth of melanoma，but anti-angiogenesis only have a mild effects.
Objective To observe the levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in aqueous humor of patients with macular edema secondary to central retinal vein occlusion (CRVO). Methods Forty eyes of 40 consecutive patients with macular edema secondary to CRVO (CRVO group) were enrolled in this study. The patients included 25 males and 15 females. The patient age ranged from 38 to 76 years. The control group was 20 patients with senile cataract who underwent phacoemulsification, including 10 males and 10 females. The levels of VEGF165, VEGF165b, IL-6 and MCP-1 in aqueous humor were determined by enzymelinked immunosorbent assay. The correlation of VEGF, and IL-6, and MCP-1 were analyzed. Results The median aqueous level of VEGF165, IL-6 and MCP-1 were 1089.0, 165.6, 1253.0 pg/ml respectively in CRVO group, which were higher than the control group's results (168.2, 4.7, 216.4 pg/ml respectively), the differences were statistically significant (Z=-4.549, -6.008, -5.343;P＜0.001). The VEGF165b in CRVO group and control group were 834.0, 915.9 pg/ml respectively, the difference was not statistically significant (Z=-0.207，P＞0.05). The ratio of VEGF165b to VEGF165 in CRVO group and control group were 2.71, 7.28 respectively, the difference was statistically significant (t=-3.007，P＜0.05). There was a highly positive correlation between IL-6 and VEGF in CRVO group (r=0.526,P=0.001) and also mild positive correlation in control group (r=0.425，P=0.070). No correlation between MCP-1 and VEGF was observed in both groups (CRVO group: r=0.211,P＞0.05. Control group: r=-0.019,P＞0.05). Conclusions VEGF165, IL-6 and MCP-1 levels were increased in CRVO patients while the VEGF165b was normal. The ratio between VEGF165b and VEGF165 in aqueous humor of patients with macular edema secondary to CRVO was decreased.
Objective To investigate the feasibility of intramuscular gene therapy for acute arterial ischemic diseases by use of plasmid pcDNA3-VEGF121 and to evaluate therapeutic efficiency of vascular endothelial growth factor(VEGF) by different routes of administration. Methods Fifty New Zealand White rabbits were randomly assigned to either gelation sponge carryingpcDNA3-VEGF121 (n=18), intramuscular injectionpcDNA3-VEGF121 (n=18), or pcDNA3 (as control group,n=14). After ligation of the external iliac artery and complete excision of the femoral artery, 500 μg of the plasmid pcDNA 3-VEGF121 were transfected into the muscles of the ischemic limb by gelation sponge carrying or direct intramuscular-injection. Immediately after gene transfection, blood flow of the internal iliac artery were measured. VEGF121gene expression was detected by RT-PCR after 2 days, 1 week, 2 weeks, 3 weeks and 4 weeks of transfection. After 30 days, blood flow of the internal iliac artery, angiographic score and histologicalvessels of ischemic hindlimbs were measured respectively. Results In the two VEGF-treated groups, VEGF121 mRNA expressed in the transfected ischemic muscles after 2 days and lasted 2 weeks. Immediately after gene transfection, blood flow of the internal iliac artery had no significant difference between three groups. After 30 days, blood flow of the internal iliac artery, angiographicscore and capillary density were significantly greater in both VEGF-treated groups than in control group. Complexity of vascular branching and vessel density of gelation sponge-VEGF treated limbs were significantly greater when comparedwith the intramuscular-injection limbs. Conclusion These findings suggest the feasibility of employing gene therapy of pcDNA3-VEGF121could augmentcollatal development and tissue perfusion in an animal model of hindlimb ischemia, andgelation sponge carrying VEGF gene may respect a potential therapy methods.
Objective To investigate the effect of Adenovirus-mediated averse vascular endothelial growth factor165（Ad-aVEGF165）on the growth of human melanoma cells(A375) in vivo and in vitro.Methods In vitro,the 100 multiplicity of infection of Aadenovirus-mediated green fluorescent protein（Ad-GFP）and Ad-aVEGF165 were transfected into human endothelium cell of vessel 304（ECV 304） and A 375. ECV 304 cells were divided into 3 groups: A 375 group, AdGFP group and AdaVEGF 165group. A375cells were also divided into 3 groups:1640 group, Ad-GFP group and AdaVEGF165 group. Their effects were analyzed by proliferation assay, cell cycle, and VEGF expression. In vivo,A375cells were injected into the axilla of the nude mouse. When the tumor formed, they were transplanted into another 15 mice. After treatment, the tumor was excised for naked eye observation, HE observation and microvascular density(MVD) counting. Results The cell supernatant fluid of A 375 group and AdGFP group could stimulate ECV304 cell growth，butthat of AdaVEGF165 group could inhibit the growth of ECV304 cell.All the A375cells in 3 groups had the proliferation trend, showing no statistically significant difference（Pgt;0.05）. ECV 304 cell proliferation index(PI) in Ad-aVEGF165group reduced（Plt;0.05）. There was no statistically significant difference（Pgt;0.05） in the PI of A 375 cell. The A 375cell integral optical densities were 234.41±13.8 in 1640 group， 222.73±3.67 in AdGFP group and 180.84±6.34 in Ad-aVEGF165group. The tumor volume in Ad-aVEGF165 group was smaller than that in Ad-GFP group and PBS group at 2 weeks after operation, the trend became much obvious with the time delay. AdaVEGF165 brought to much tissue necrosis under HE stain. The MVD of PBS group, Ad-GFP group and Ad-aVEGF165group were 65 10/view,52±11/view and 30±6/view, respectively. Conclusion In Vitro, Ad-VEGF 165gene could inhibited ECV304 cells’ growth by weakening VEGF expression of A 375cells. In vivo, Ad-aVEGF 165could inhibit the growth of human melanoma from blockinmicrovascular.
Objective To investigate the expression of vascular endothelial growth factor-A （VEGF-A） and the phenotypic transition after the activation of fibroblasts by the supernatant of cultured tumor cells．Methods The growth tendency of fibroblasts was tested by the MTT assay．The expressions of alpha-smooth muscle actin （α-SMA） and VEGF-A mRNA were tested by RT-PCR．The expressions of α-SMA and VEGF-A protein were tested by immunohistochemistry and Western blot．Results The MTT assay indicated that the conditional medium which contained tumor cells supernatant could obviously promote the growth of the fibroblasts． RT-PCR and Western blot manifested that α-SMA expressed by the fibroblasts which cultured by normal medium reached its peak on day 5，then decreased to a low level on day 7．When the medium contained 2 ng/ml transforming growth factor-β1 （TGF-β1），the fibroblasts could steadily express more α-SMA．But the above two mediums could not make the fibroblasts express the VEGF-A. When using the conditional medium，the α-SMA peak advanced on the third day and maintained at a high level，so as the expression of the VEGF-A．Conclusions The results suggested that fibroblasts can be activated to be myofibroblasts when using the conditional medium．The best activation time of the fibroblasts is consistent with the time of the VEGF-A expression at the highest level by the activated fibroblasts．The fibroblasts which activated at the best time are expected to become a kind of cells which can be used for promoting revascularization．
Objective To compare the transfection effects on soluble fms-like tyrosine kinase receptor-1 (sFlt-1) gene (2-4 transcellular region) mediated by carboxymethylated dextran coated nanoparticle and lipofectamineTM2000.Methods The plasmid pcDNA3.1-EGFP/sFlt-1(2-4) was constructed and assessed by enzyme cut, electrophoresis, and genetic sequencing. Three groups were divided: nanoparticle group, lipofectamine group, and non-transfected group. Twenty-four and 48 hours after the transfection, the distribution of cellular green fluorescence was oberved under the inverted phase contrast fluorescence microscope; the expression rate of green fluorescence was measured by flow cytometry; the expression of sFlt-1(2-4)mRNA and the protein was detected by reverse transcriptionpolymerase chain reaction (RT-PCR) and Western blot; the growth of the cells was observed by methyl thiazolyl tetrazolium (MTT) colorimetry and the relative growth rate (RGR) of the cells in each group was calculated; the cellular apoptosis in each group was detected by Hoechst staining.Results The sequence of sFlt-1(2-4) gene was equal to 915 base pair (bp).The transfection rate was 45% in nanoparticle group and 21% in lipofectamine group; the difference between the two groups was significant (t=2.541，Plt;0.05). Forty-eight hours after the transfection, the expression of sFlt-1（2-4）mRNA and protein was obviously higher in nanoparticle group than that in lipofectamine group (t=2.454，2.398；Plt;0.05) . Twenty-four and 48 hours after the transfection,the difference of RGR of the cells between nanoparticle and non-transfected group was not significant（t=1.436，Pgt;0.05）; the RGR in lipofectamine group differed much from that in non-transfected and nanoparticle group (t=2.412，2.545; Plt;0.05) ; the difference of cellular apoptosis was not significant between nanoparticle and nontransfected group (t=1.436，Pgt;0.05), but significant between nanoparticle and lipofectamine group (t=2.236，Plt;0.05). Conclusion The transfection rate of sFlt-1(2-4) mediated by carboxymethylated dextran coated nanoparticle was higher than that mediated by lipofectamineTM2000.
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 explore a new method of treating early avascular necrosis of femoral head (AVNFH). Methods Sixty-nine New Zealand adult rabbitswith a mean weight of 2.8 kg after AVNFH presenting were randomly divided into three groups. In group A, deproteinized bone(DPB) combined with the recombinant plasmid pcDNA3.1/vascular endothelial growth factor 165(VEGF165) was implanted in the drilled channel of the necrotic femoral head. In group B, only DPB was implanted. In group C, channel was drilled without DPB or plasmid implanted. Femoral head specimens were obtained 3 days, 1, 2, 4, 8 and 16 weeks after operation. The expression of VEGF165 was examined by RT-PCR, Western blot and immunohistochemical techniques. X-ray testedbone formation generally. Angiogenesis and repair of the femoral head were observed by histological and histomorphometric analysis. Results In group A, the expressions of VEGF165 mRNA and protein were detected 3 days postoperatively, reached apex 1 week and lasted more than 3 weeks after implantation. The ratios of IOD of collagen type Ⅰ were 0.29±0.11, 0.55±0.13 and 0.67±0.10 IOD/μm2 respectively at 2, 4 and 8 weeks postoperatively and the ratios of IOD of new capillary vessels were 0.33±0.10and 0.57±0.16 IOD/μm2 respectively at 2, 4 weeks postoperatively in group A, showing statistically significant difference (Plt;0.01) when compared with groups B and D. X-ray test indicated much bone callus formed early. Conclusion Transfection of the VEGF165 gene can enhance local angiogenesis at early stage andDPBVEGF165 compound can improve bone formation. Deproteinized bone combined with VEGF165 gene provides a potential method for therapy of osteonecrosis.
Objective To explore the effect of toremifene on estrogen receptor （ER） expression and tumor micro-angiogenesis in rat Lewis lung carcinoma. Methods Cell suspension of rat Lewis lung carcinoma was implanted into 40 female Wistar rats subcutaneously. The rats were randomly divided into a control group，a estradiol group （0.006 mg/mL），a low dose toremifene group （0.25 mg/mL） and a high dose toremifene group （5 mg/mL）. Tumor size was measured every 3 days and the tumor growth curve was charted. On 15th day，the tumor weight and the growth inhibition rate were measured. Immunohistochemical method was used to detect the expressions of estrogen receptor α （ERα），estrogen receptor β （ERβ），vascular endothelial growth factor （VEGF），and platelet endothelial cell adhesion molecule-1 （PECAM-1）. Integral optical density （IOD） of ERα，ERβ and VEGF was calculated by image analysis software. Quantitative method of Weidner with PECAM-1 was employed for microvessel density （MVD） count. Results Tumor size of the four groups all presented a quadratic function growth trend with time （Plt;0.05）. Tumor growth speed was slower in toremifene groups of low and high doses than that in the control group and the estradiol group. The growth inhibition rate of the estradiol group，the low dose toremifene group and the high dose toremifene group was －15.1%，22.6%，and 45.1%，respectively. The expressions of ERα，VEGF，and MVD in the estradiol group were significantly higher than those in the control group，the low dose toremifene group and the high dose toremifene group （all Plt;0.05）. The expressions of ERα，VEGF，and MVD in the low dose toremifene group were significantly lower than those in control group，but higher than those in high dose toremifene group （all Plt;0.05）.The expression of ERα was positively related to VEGF （r=0.664，Plt;0.05） and MVD（r=0.593，Plt;0.05）. Conclusion Toremifene can inhibit tumor growth，which maybe involved in inhibiting ERα mediated VEGF expression.