Three important components in the regeneration of the cavernous nerve： brain-derived neurotrophic factor, vascular endothelial growth factor and the JAK/STAT signaling pathway

Retroperitoneal operations, such as radical prostatectomy, often damage the cavernous nerve, resulting in a high incidence of erectile dysfunction. Although improved nerve-sparing techniques have reduced the incidence of nerve injury, and the administration of phosphodiesterase type 5 inhibitors has revolutionized the treatment of erectile dysfunction, this problem remains a considerable challenge. In recent years, scientists have focused on brain-derived neurotrophic factor and vascular endothelial growth factor in the treatment of cavernous nerve injury in rat models. Results showed that both compounds were capable of enhancing the regeneration of the cavernous nerve and that activation of the Janus kinase （JAK）/signal transducer and activator of transcription （STAT） pathway played a major role in the process.

THE RELATIONSHIP BETWEEN PERITUMORAL BRAIN EDEMA AND VASCULAR ENDOTHELIAL GROWTH FACTOR EXPRESSION IN PATIENTS WITH MENINGIOMA

Objective: To determine whether VEGF plays a role in the development of peritumoral brain edema. Methods 50 meningioma patients and their VEGF expression were studied. We took a monoclonal antibody from mouse to VEGF to stain the tumor cells, the vascular endothelial cells and the interstitial cells. The severity of brain edema was evaluated according to CT or MR scans by the following equation: edema index= V tumor +edema /Vtumor. The relationship between VEGF expression and edema index was analyzed statistically. Results VEGF was expressed in meningioma tumor cells, which is usually concentrated at the peripheral sites of the tumor. There was a positive linear correlation between the expression and the brain edema index. Conclusion VEGF may play a role in the development of peritumoral brain edema in meningioma patient.

Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy

AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P【 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma.

Serum vascular endothelial growth factor is a potential biomarker of metastatic recurrence after curative resection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. To date, surgery is still the best solution to it. However, metastatic recurrences after curative hepatic resections are very common. Tang et al have reported that recurrence rate within 5 years of curative hepatic resection is 61.5% [1]. As curative hepatic resection has a high tendency for metastatic recurrence, therapeutic interventions such as transarterial embolization and antiangiogenesis have been tried to further improve prognosis of HCC patients. Therefore, establishing a dependable, sensitive, easy, and economical method to predict metastatic recurrence following curative hepatic resection is of clinical urgency.

Correlative studies on uPA mRNA and uPAR mRNA expression with vascular endothelial growth factor, microvessel density, progression and survival time of patients with gastric cancer

AIM： To investigate the correlations between the expression of urokinase-type plasminogen activator （uPA） mRNA, uPA receptor （uPAR） mRNA and vascular endothelial growth factor （VEGF） protein and clinicopathologic features, microvessel density （MVD） and survival time. METHODS： In situ hybridization and immuno-histochemistry techniques were used to study the expressions of uPA mRNA, uPAR mRNA, VEGF and CD34 protein in 105 gastric carcinoma specimens. RESULTS： Expressions of uPA mRNA, uPAR mRNA and VEGF protein were observed in 61 （58.1%） cases, 70 （66.7%） cases and 67 （63.8%） cases, respectively. The uPA mRNA and uPAR mRNA positive expression rates in infiltrating-type cases （73.7%, 75.4%）, stage Ⅲ- Ⅳ （72.1%, 75.4%）, vessel invasion （63.2%, 69.9%）, lymphatic metastasis （67.1%, 74.4%） and distant metastasis （88.1%, 85.7%） were significantly higher than those of the expanding-type （χ^2 = 15.57, P = 0.001; χ^2 = 6.91, P = 0.046）, stage Ⅰ-Ⅱ （χ^2 = 19.22, P = 0.001; χ^2 = 16.75, P = 0.001）, non-vessel invasion （χ^2 = 11.92, P = 0.006; χ^2 = 14.15, P = 0.002）, non- lymphatic metastasis （χ^2 = 28.41, P = 0.001; χ^2 = 22.5, P = 0.005） and non-distant metastasis （χ^2 = 12.32, P = 0.004; χ^2 = 17.42, P = 0.002; χ^2 = 11.25, P = 0.012; χ^2 = 18.12, P = 0.002）.The VEGF positive expression rates in infiltrating-type cases （75.4%）, stage Ⅲ-Ⅳ （88.5%）, vessel invasion （82.9%）, lymphatic metastasis （84.3%） and distant metastasis （95.2%） were significantly higher than those of the expanding-type （χ^2 = 9.61, P = 0.021）,stage Ⅰ-Ⅱ （χ^2 = 16.66, P = 0.001）, non-vessel invasion （χ^2 = 29.38, P = 0.001）, non-lymphatic metastasis （χ^2 = 18.68, P = 0.005）, and non-distant metastasis （χ^2 = 22.72, P = 0.007; χ^2 = 21.62, P = 0.004）. The mean MVD in the specimens positive for the uPA mRNA, uPAR mRNA and VEGF protein was markedly higher than those with negative expression groups. Moreover, a positive relation between MVD and uPA mRNA （rs = 0.199, P = 0.042）, uPAR mRNA （rs = 0.278, P = 0.035）, and VEGF （rs = 0.398, P = 0.048） expressions was observed. The mean survival time in cases with positive uPA mRNA, uPAR mRNA and VEGF protein expression or MVD value ≥54.9 was significantly shorter than those in cases with negative expression or MVD value 〈 54.9. CONCLUSION： uPA and uPAR expressions are correlated with enhanced VEGF-induced tumor angiogenesis and may play a role in invasion and nodal metastasis of gastric carcinoma, thereby serving as prognostic markers of gastric cancer.

Vascular endothelial growth factor A promotes platelet adhesion to collagen Ⅳ and causes early brain injury after subarachnoid hemorrhage

The role of vascular endothelial growth factor A in platelet adhesion in cerebral microvessels in the early stage of subarachnoid hemorrhage remains unclear.In this study,the endovascular puncture method was used to produce a rat model of subarachnoid hemorrhage.Then,30 minutes later,vascular endothelial growth factor A antagonist anti-vascular endothelial growth factor receptor 2 antibody,10μg,was injected into the right ventricle.Immunohistochemistry and western blot assay were used to assess expression of vascular endothelial growth factor A,occludin and claudin-5.Immunohistochemical double labeling was conducted to examine co-expression of GP Ⅰa-Ⅱ integrin and type Ⅳ collagen.TUNEL was used to detect apoptosis in the hippocampus.Neurological score was used to assess behavioral performance.After subarachnoid hemorrhage,the expression of vascular endothelial growth factor A increased in the hippocampus,while occludin and claudin-5 expression levels decreased.Co-expression of GP Ⅰa-Ⅱ integrin and type Ⅳ collagen and the number of apoptotic cells increased,whereas behavioral performance was markedly impaired.After treatment with anti-vascular endothelial growth factor receptor 2 antibody,occludin and claudin-5 expression recovered,while co-expression of GP Ⅰa-Ⅱ integrin and type Ⅳ collagen and the number of apoptotic cells decreased.Furthermore,behavioral performance improved notably.Our findings suggest that increased vascular endothelial growth factor A levels promote platelet adhesion and contribute to early brain injury after subarachnoid hemorrhage.This study was approved by the Biomedical Ethics Committee,Medical College of Xi’an Jiaotong University,China in December 2015.

Serum Vascular Endothelial Growth Factor Levels in Patients with Non-small Cell Lung Cancer and Its Relations to the Micrometastasis in Peripheral Blood

To examine the relationship between the levels of the serum vascular endothelial growth factor （VEGF） and the micrometastasis of peripheral blood in patients with non-small cell lung cancer （NSCLC）, 108 NSCLC patients, including 40 patients with benign lung diseases and 30 healthy controls, were investigated. The serum VEGF levels were detected by ELISA and CK19 mRNA in peripheral blood by reverse transcriptase-polymerase chain reaction （RT-PCR）. In NSCLC group, the serum VEGF levels and the positive rate of CK19 mRNA in peripheral blood were 479.8±268.5 pg/mL and 66.7%, which were significantly higher than those of the other two groups respectively （P〈0.01）, and both of them were increased significantly with the progression of clinical stage of the tumors （P〈0.01）. Serum VEGF levels as well as the positive rate of CK19 mRNA in different pathological types of lung cancer had no significant differences （P〉0.05）. Serum VEGF levels in the patients positive for CK19 mRNA was 561.7±325.6 pg/mL. It is significantly higher than that in the negative patients （P〈0.01）. There existed a significant correlation between serum VEGF levels and expression of CK19 mRNA in peripheral blood in NSCLC patients （P〈0.001）. The detection of serum VEGF levels and CK19 mRNA in peripheral blood is helpful in judging the condition and the prognosis of NSCLC patients, and serum VEGF levels and CK19 mRNA are independent of the pathological types of lung cancer. The micrometastasis in peripheral blood of NSCLC patients is significantly associated with serum VEGF levels.

C-reactive protein,procalcitonin,interleukin-6,vascular endothelial growth factor and oxidative metabolites in diagnosis of infection and staging in patients with gastric cancer

AIM:The current study was to determine the serum/pLasma levels of VEGF,IL-6,malondialdehyde (MDA),nitric oxide (NO),PCT and CRP in gastric carcinoma and correlation with the stages of the disease and accompanying infection. METHODS:We examined the levels of serum VEGF,IL-6, PCT,CRP and plasma MDA,NO in 42 preoperative gastric cancer patients and 23 healthy subjects.There were infection anamneses that had no definite origin in 19 cancer patients. RESULTS:The VEGF levels (mean±SD; pg/mL) were 478.05±178.29 and 473.85±131.24 in gastric cancer patients with and without infection,respectively,and these values were not significantly different (P>0.05).The levels of VEGF, CRP,PCT,It-6,MDA and NO in cancer patients were significantly higher than those in healthy controls and the levels of CRP,PCT,It-6,MDA and NO were statistically increased in infection group when compared with non- infection group (P<0.001). CONCLUSION:Although serum VEGF concentrations were increased in gastric cancer,this increase might not be related to infection.CRP,PCT,IL-6,MDA and NO have obvious drawbacks in the diagnosis of infections in cancer patients. These markers may not help to identify infections in the primary evaluation of cancer patients and hence to avoid unnecessary antibiotic treatments as well as hospitalization. According to the results of this study,IL-6,MDA,NO and especially VEGF can be used as useful parameters to diagnose and grade gastric cancer.

Neuron-specific enolase expression in a rat model of radiation-induced brain injury following vascular endothelial growth factor-modified neural stem cell transplantation

BACKGROUND： Previous studies have shown that transplantation of vascular endothelial growth factor （VEGF）-modified neural stem cells （NSC） provides better outcomes, compared with neural stem cells, in the treatment of brain damage. OBJECTIVE： To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury, and to determine neuron-specific enolase （NSE） expression in the brain. DESIGN, TIME, AND SETTING： The randomized, controlled study was performed at the Linbaixin Experimental Center, Second Affiliated Hospital, Sun Yat-sen University, China from November 2007 to October 2008. MATERIALS： VEGF-modified C17.2 NSCs were supplied by Harvard Medical School, USA. Streptavidin-biotin-peroxidase-complex kit （Boster, China） and 5, 6-carboxyfluorescein diacetate succinimidyl ester （Fluka, USA） were used in this study. METHODS： A total of 84 Sprague Dawley rats were randomly assigned to a blank control group （n = 20）, model group （n = 20）, NSC group （n = 20）, and a VEGF-modified NSC group （n = 24）. Rat models of radiation-induced brain injury were established in the model, NSC, and VEGF-modified NSC groups. At 1 week following model induction, 10 pL （5 ×10^4 cells/μL） VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups. A total of 10μL saline was injected into rats from the blank control and model groups. MAIN OUTCOME MEASURES： NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation. RESULTS： NSE expression was significantly decreased in the brains of radiation-induced brain injury rats （P 〈 0.05）. The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups, compared with the model group （P 〈 0.05）. NSE expression significantly increased in the VEGF-modified NSC group, compared with the NSC group, at 6 weeks following transplantation （P 〈 0.05）. CONCLUSION： VEGF-modified NSC transplantation increased NSE expression in rats with radiation-induced brain injury, and the outcomes were superior to NSC transplantation.

Correlation of vascular endothelial growth factor to permeability of blood-brain barrier and brain edema during high-altitude exposure

BACKGROUND： Many studies have evaluated the role of vascular endothelial growth factor （VEGF） in traumatic brain edema and hemorrhagic brain edema. OBJECTIVE： To observe the effects of VEGF expression on permeability of the blood-brain barrier （BBB） during high-altitude and hypoxia exposure, and to investigate the correlation between VEGF expression and BBB permeability with regard to Evans blue staining and brain edema during high-altitude exposure. DESIGN, TIME AND SETTING： The randomized, controlled, animal study was performed at the Tanggula Etape, Central Laboratory of Chengdu Medical College, and Central Laboratory of General Hospital of Chengdu Military Area Command of Chinese PLA, China, from July 2003 to November 2004. MATERIALS： Quantitative RT-PCR kit （Sigma, USA）, VEGF ELISA kit （Biosource, USA）, and Evans blue （Jingchun, China） were acquired for this study. METHODS： A total of 180 Wistar rats were equally and randomly assigned to 15 groups： low-altitude （500 m）, middle-altitude （2 880 m）, high-altitude （4 200 m）, super-high-altitude （5 000 m）, 1,3, 5, 7, 9, 11, 13, 15, 17, 19, and 21 days of super high-altitude exposure. Wistar rats were exposed to various altitude gradients to establish a hypoxia model. MAIN OUTCOME MEASURES： Brain water content was calculated according to the wet-to-dry weight ratio. BBB permeability to Evans blue was determined by colorimetric method. VEGF mRNA and protein levels in brain tissues were detected using RT-PCR and double-antibody sandwich ELISA. RESULTS： Brain water content, BBB permeability to Evans blue, and VEGF mRNA and protein levels in brain tissues increased with increasing altitude and prolonged exposure to altitude. The greatest increase was determined on day 9 upon ascending 5 000 m. Simultaneously, VEGF expression positively correlated to BBB permeability of Evans blue and brain water content （r = 0.975, 0.917, P〈 0.01）. CONCLUSION： Increased VEGF protein and mRNA expression was responsible for increased BBB permeability, which may be an important mechanism underlying brain edema during high-altitude exposure.

Expression of vascular endothelial growth factor and its prognostic significance in gastric carcinoma

AIMS To investigate the clinical significance of vas- cular endothelial growth factor (VEGF) expression in gastric carcinoma. METHODS The expression of VEGF in 128 gastric carcinomas was investigated by immunohistochemical staining with a polyclonal antibody against VEGF. Cor- relations between the expression of VEGF and various clinicopathologic factors and prognosis were studied. RESULTS The VEGF-rich expression rate was 64.1% in gastric carcinoma. VEGF-rich expression rate of patients with stage Ⅲ and stage Ⅳ disease was greater than that of patients with stage f disease (P <0.05). Significant differences of expression rate ex- isted with respect to growth pattern,serosal invasion and lymph node metastasis. The VEGF-rich rate was much higher in tumors with expanding growth pattern (71.8%) or serosal invasion (73.5%) than in those with infiltrative growth pattern (52.0%) or non-serosal invasion (53.3%) (P<0.025,respectively),and it was also significantly higher in patients with lymph node metastases (75.0%) than in those without such metastases (50.0%) (P<0.05). In addition,postop- erative survey of 86 patients who had been followed up for at least 5 years demonstrated that the 5-year sur- vival rate of patients with VEGF-rich tumors was signifi- cantly lower than that of patients with VEGF-poor tu- mors (P<0.05). CONCLUSIONS The expression of VEGF may be as- sociated with the invasion and metastasis and may also be a useful prognostic indicator of gastric carcinoma.

Expression of vascular endothelial growth factor and its role in oncogenesis of human gastric carcinoma

AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.

Early expressions of hypoxia-inducible factor 1alpha and vascular endothelial growth factor increase the neuronal plasticity of activated endogenous neural stem cells after focal cerebral ischemia

Endogenous neural stem cells become ＂activated＂ after neuronal injury, but the activation sequence and fate of endogenous neural stem cells in focal cerebral ischemia model are little known. We evaluated the relationships between neural stem cells and hypoxia-inducible factor-1α and vascular endothelial growth factor expression in a photothromobotic rat stroke model using immunohistochemistry and western blot analysis. We also evaluated the chronological changes of neural stem cells by 5-bromo-2′-deoxyuridine（BrdU） incorporation. Hypoxia-inducible factor-1α expression was initially increased from 1 hour after ischemic injury, followed by vascular endothelial growth factor expression. Hypoxia-inducible factor-1α immunoreactivity was detected in the ipsilateral cortical neurons of the infarct core and peri-infarct area. Vascular endothelial growth factor immunoreactivity was detected in bilateral cortex, but ipsilateral cortex staining intensity and numbers were greater than the contralateral cortex. Vascular endothelial growth factor immunoreactive cells were easily found along the peri-infarct area 12 hours after focal cerebral ischemia. The expression of nestin increased throughout the microvasculature in the ischemic core and the peri-infarct area in all experimental rats after 24 hours of ischemic injury. Nestin immunoreactivity increased in the subventricular zone during 12 hours to 3 days, and prominently increased in the ipsilateral cortex between 3–7 days. Nestin-labeled cells showed dual differentiation with microvessels near the infarct core and reactive astrocytes in the peri-infarct area. BrdU-labeled cells were increased gradually from day 1 in the ipsilateral subventricular zone and cortex, and numerous BrdU-labeled cells were observed in the peri-infarct area and non-lesioned cortex at 3 days. BrdU-labeled cells rather than neurons, were mainly co-labeled with nestin and GFAP. Early expressions of hypoxia-inducible factor-1α and vascular endothelial growth factor after ischemia made up the microenvironment to increase the neuronal plasticity of activated endogenous neural stem cells. Moreover, neural precursor cells after large-scale cortical injury could be recruited from the cortex nearby infarct core and subventricular zone.

Cyclooxygenase-2 promotes angiogenesis by increasing vascular endothelial growth factor and predicts prognosis in gallbladder carcinoma

AIM: To investigate the relationships between the expression of cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF) and the degree of vascularization, clinicopathologic feature, survival time of patients with gallbladder carcinomas. METHODS: Sixty-four gallbladder carcinoma specimens were evaluated for COX-2, VEGF expression by immunohi stochemical methods. Microvessel counts (MVC) were determined using CD34. The relationships between COX-2, VEGF expression, CD34-stained MVC, clinicopathologic features and survival time were analyzed. The correlations between COX-2 and VEGF expression, CD34-stained MVC were also investigated. RESULTS: COX-2, VEGF immunoreactivity were observed in 71.9% (46/64) and 54.7% (35/64) specimens, respectively. The average MVC in 64 cases of gallbladder carcinoma was 57±14 per high power vision field. The status of MVC was closely correlated with Nevin staging, tumor differentiation and lymph node metastasis (P<0.01, 0.002, and 0.003, 0.000, respectively). Increased VEGF expression was significantly correlated with tumor differentiation (poorly and moderately>well differentiated, P<0.05, P = 0.016). Clinical stages had no relation with the expression of VEGF (P>0.05, P = 0.612). There was a positive correlation between COX-2 expression and clinical stages. The positive rate of COX-2 was higher in cases of Nevin stages S4-S5 (81.8%) than in those of Nevin stages S1-S3 (50.0%) with a statistical significance (P0.01, P = 0.009). The expression of COX-2 did not vary with differentiation (P>0.05, P= 0.067). Statistically significant differences were also observed according to lymph node metastasis, COX-2 expression and VEGF expression (P<0.01,0.000, and 0.001, respectively). There was no relation between VEGF, COX-2 expression, MVC and the age and sex of patients. MVC and VEGF positive rate in the COX-2 positive gallbladder carcinoma tissue was higher than that in the COX-2 negative tissue (P<0.05, 0.000, and 0.032, respectively). Patients with VEGF, COX-2 positive tumors had a significantly shorter survival time than those with negative tumors (P<0.05,0.004, 0.01, respectively). CONCLUSION: Augmented tumor neovascularization induced by VEGF may be one of the several effects of COX-2 responsible for poor prognosis of human gallbladder carcinoma. COX-2 inhibitor, either in combination therapy with other agents, or for chemoprevention, may be effective via suppression of angiogenesis in this fatal disease.

Effects of endostatin on expression of vascular endothelial growth factor and its receptors and neovascularization in colonic carcinoma implanted in nude mice

AIM:To investigate the antiangiogenic effects of endostatin on colonic carcinoma cell line implanted in nude mice and its mechanism. METHODS:Nude mice underwent subcutaneous injection with LS-174t colonic carcinoma cell line to generate carcinoma and were randomly separated into two groups.Mice received injection of vehicle or endostatin every day for two weeks. After the tumor was harvested,the tumor volumes were determined,and the expressions of CD34,VEGF and FIk-1 were examined by immunohistochemical method. RESULTS:Tumor volume was significantly inhibited in the endostatin group(84.17%)and tumor weight was significantly inhibited in the endostatin group(0.197±0.049) compared to the control group(1.198±0.105)(F=22.56, P=0.001),microvessel density(MVD)was significantly decreased in the treated group(31.857±3.515)compared to the control group(100.143±4.290)(F=151.62,P<0.001). Furthermore,the expression of FIk-1 was significantly inhibited in the treated group(34.29%) ompared to the control group(8.57%)(X^2=13.745,P=0.001).However no significant decrease was observed in the expression of vascular endothelial growth factor(VEGF)between these two groups(X^2=0.119,P=0.730). CONCLUSION:Endostatin can inhibit tumor growth and angiogenesis by blocking Vegf/FIk-1 pathway.This experiment provides the theory basis for developing a new anti-carcinoma drug through studying the properties of anti-angiogenesis inhibitors.

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）

The predictive value of vascular endothelial growth factor and Ki-67 expression on neoadjuvant therapy in rectal cancer

Objective： To investigate the expressions of vascular endothelial growth factor （VEGF） and proliferating cell nuclear antigen （Ki-67） in patients with rectal adenocarcinoma and their associations with neoadjuvant therapy. Methods： The expressions of Ki-67 and VEGF in 32 cases of rectal adenocarcinoma, including both pretreatment tumor biopsies and postoperative specimen, were detected by immunohistochemistry using specific antibodies, and were correlated with clinicopathological factors. Results： The intensity of VEGF staining was significantly correlated with lymph nodal metastasis （P =0.033）, depth of tumor invasion （P =0.007） and tumor stage （P= 0.016）, but not with histological types, tumor sizes, patients＇ ages and genders （P 〉 0.05）. Low level of VEGF expression had significant correlation with the high sensitivity of response to neoadjuvant therapy （P = 0.016）. The transient increase of VEGF expression could be seen after neoadjuvant therapy （P = 0.035）. Ki-67 labeling index （Ki-67-LI） was significantly correlated with lymph node metastasis （P = 0.028）, but not correlated to tumor sizes, patients＇ ages and genders （P 〉 0.05）. Tumors with lower Ki-67-LI were more sensitive to neoadjuvant therapy （P = 0.032）. The Ki-67 level decreased after neoadjuvant therapy, but no statistical significance was found （P 〉 0.05）. Conclusion： Our results demonstrate that the expression of VEGF and Ki-67 in pretreatment rectal adenocarcinoma biopsies may be predictive of tumor response to neoadjuvant therapy.

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.

Vascular endothelial growth factor polymorphisms and risk of lung cancer

Objective:We investigated the potential association between vascular endothelial growth factor(VEGF) polymorphisms and the risk of lung cancer.Methods:In the case-control study, we used PCR-RFLP technique to determine two VEGF genotypes-2578C/A and 936C/T in 171 lung cancer patients and 172 healthy controls for conformation, and constructed haplotypes of the two gene sites by PHASE1.0 software.Unconditional logistic regression model was used to analyze the statistical association of genontypes or haplotypes in the two groups adjusted by gender and age.Results:Compared with at least one-2578A allele, individuals with-2578CC genotype found associated with a significantly decreased risk of lung cancer P=0.001;adjusted odds ratio(OR), 0.391;95% confidence interval(95% CI), 0.226-0.686.Analyses stratified by gender showed that the combined-2578 CA and AA genotype were also associated with a significantly decreased risk of lung cancer.(P = 0.016;OR = 0.303;95% CI = 0.153-0.601 and P = 0.018;OR = 0.547;95% CI = 0.331-0.903, respectively).The distribution of the two haplotypes(936C/-2578C and 936C/-2578A) were significantly different between case-and-control groups(P = 0.016, OR = 0.317, 95% CI = 0.124-0.809 and P = 0.018, OR = 0.547, 95% CI = 0.331-0.903).Analyses categorized by tumor histology showed that Haplotype C-C was associated with a significantly decreased risk of adenocarcinoma compared with the reference haplotypes.(P = 0.004;OR = 0.237;95% CI = 0.090-0.627).Conclusion:These results suggest that the VEGF polymorphisms may be a critical factor for the risk of lung cancer.

Vascular endothelial growth factor promotes angiogenesis in gastric carcinoma

Objective: To explore the role of vascular endothelial growth factor (VEGF) in the angiogenesis and development of human gastric carcinoma. Methods: The expressions of VEGF and its receptor KDR (ki-nase-domain insert containing receptor) in human gastric cancer tissue and SGC-7901 cells were detected with immunohistochemical staining. Microvessel density (MVD) was obtained after immunostaining for Factor-VIII. VEGF in SGC-7901 cell line was detected with Western blot. VEGF levels were manipulated in human gastric cancer cell by using eukaryotic expression vector containing the complete VEGF165 complimentary DNA in either the sense or antisense orientation. Finally the biological characteristics of the transfectants were identified. Results: VEGF-positive rate in TNM grade I and IV gastric carcinomas (19. 0%) were significantly higher than that in grade I and I (72. 4%) (P<0. 05). Increased MVD was found in VEGF-positive tumors (16. 4±6. 7). which is significantly larger than in VEGF-negative tumors (6. 5±2. 1) (P< 0. 05). Human gastric cancer cells (SGC-7901) produced 3 kinds of VEGF in molecule. In 2 cases of 50 specimens, a few gastric cancer cells expressed KDR in cytoplasm and cell membranes. SGC-7901 cells with anti-sense VEGF165 showed a significant reduction in cell surface VEGF protein with the immunofluorescence intensity from 8. 9% to 31. 6% (P<0. 05). However, those with stable integration of VEGF165 in the sense orientation resulted in an increase in cellular and cell surface VEGF with the immunofluorescence intensity from 75. 4% to 31. 6% (P<0. 05). The decrease of VEGF levels was associated with a marked decrease in the growth of nude mouse xenografted tumor (33 d post-implantation, 345. 4±136. 3 mm3 in size) (P<0. 05 vs control SGC-7901 group) , whereas VEGF overexpression resulted in an increase of xenografted tumor size (33 d post-implantation, 2 350. 5±637. 7 mm3 in size) (P<0. 05 vs control SGC-7901 group). Conclusion: VEGF plays an important role in the development of human gastric cancer, and might have an autocrine effect upon the gastric cancer cells. The inhibition of VEGF by antisense RNA expression might prevent solid tumor from growing and metastasizing.