Hypoxia-inducible factor 1alpha and vascular endothelial growth factor in Glioblastoma Multiforme:a systematic review going beyond pathologic implications

Glioblastoma multiforme(GBM)is an aggressive primary brain tumor characterized by extensive heterogeneity and vascular proliferation.Hypoxic conditions in the tissue microenvironment are considered a pivotal player leading tumor progression.Specifically,hypoxia is known to activate inducible factors,such as hypoxia-inducible factor 1alpha(HIF-1α),which in turn can stimulate tumor neo-angiogenesis through activation of various downward mediators,such as the vascular endothelial growth factor(VEGF).Here,we aimed to explore the role of HIF-1α/VEGF immunophenotypes alone and in combination with other prognostic markers or clinical and image analysis data,as potential biomarkers of GBM prognosis and treatment efficacy.We performed a systematic review(Medline/Embase,and Pubmed database search was completed by 16th of April 2024 by two independent teams;PRISMA 2020).We evaluated methods of immunoassays,cell viability,or animal or patient survival methods of the retrieved studies to assess unbiased data.We used inclusion criteria,such as the evaluation of GBM prognosis based on HIF-1α/VEGF expression,other biomarkers or clinical and imaging manifestations in GBM related to HIF-1α/VEGF expression,application of immunoassays for protein expression,and evaluation of the effectiveness of GBM therapeutic strategies based on HIF-1α/VEGF expression.We used exclusion criteria,such as data not reporting both HIF-1αand VEGF or prognosis.We included 50 studies investigating in total 1319 GBM human specimens,18 different cell lines or GBM-derived stem cells,and 6 different animal models,to identify the association of HIF-1α/VEGF immunophenotypes,and with other prognostic factors,clinical and macroscopic data in GBM prognosis and therapeutic approaches.We found that increased HIF-1α/VEGF expression in GBM correlates with oncogenic factors,such as miR-210-3p,Oct4,AKT,COX-2,PDGF-C,PLDO3,M2 polarization,or ALK,leading to unfavorable survival.Reduced HIF-1α/VEGF expression correlates with FIH-1,ADNP,or STAT1 upregulation,as well as with clinical manifestations,like epileptogenicity,and a favorable prognosis of GBM.Based on our data,HIF-1αor VEGF immunophenotypes may be a useful tool to clarify MRI-PET imaging data distinguishing between GBM tumor progression and pseudoprogression.Finally,HIF-1α/VEGF immunophenotypes can reflect GBM treatment efficacy,including combined first-line treatment with histone deacetylase inhibitors,thimerosal,or an active metabolite of irinotecan,as well as STAT3 inhibitors alone,and resulting in a favorable tumor prognosis and patient survival.These data were supported by a combination of variable methods used to evaluate HIF-1α/VEGF immunophenotypes.Data limitations may include the use of less sensitive detection methods in some cases.Overall,our data support HIF-1α/VEGF’s role as biomarkers of GBM prognosis and treatment efficacy.

Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis

BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have always been unsatisfactory.AIM To investigate the correlation between vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGFβ1)expression and prognosis in older adults with AML.METHODS This study enrolled 80 patients with AML(AML group),including 36 with complete response(AML-CR),23 with partial response(AML-PR),and 21 with no response(AML-NR).The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls.Kaplan-Meier analysis was performed to assess overall survival(OS)and progression-or disease-free survival(DFS).Prognostic risk factors were analyzed using a Cox proportional hazards model.RESULTS The AML group showed a VEGF level of 2.68±0.16.VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR(P<0.05).TGFβ1 expression in the AML group was 0.33±0.05.Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR(P<0.05).VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes,platelets,hemoglobin,and peripheral blood immature cells(P<0.05);Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression(P<0.05),whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels(P<0.05).VEGF,TGFβ1,and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS(P<0.05),while VEGF,TGFβ1,and white blood cell count were independent risk factors for DFS(P<0.05).CONCLUSION Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies.

Vascular endothelial growth factor pathway’s influence on bevacizumab efficacy in metastatic colorectal cancer treatment

In this article,an article published in the World Journal of Gastrointestinal Oncology,which focuses on whether the expression of programmed death-ligand 1(PD-L1)affects the effectiveness of chemotherapy regimens,including bevacizumab,in treating patients with colorectal cancer(CRC).Through neutralization of vascular endothelial growth factor(VEGF),bevacizumab inhibits tumor angiogenesis,impairing neovascularization and thereby depriving the tumor of essential nutrients and oxygen.Conversely,PD-L1 binding to VEGF receptor 2 promotes angiogenesis,supporting tumor vasculature.The interplay between these pathways complicates the assessment of bevacizumab’s efficacy in cancer therapy,notably in CRC,where VEGF and PD-L1 significantly affect treatment response.This review examines metastatic CRC treatment strategies,focusing on bevacizumab’s mechanism of action and the role of PD-L1 in this therapeutic context.

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

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

Clinicopathological and prognostic significance of galectin-1 and vascular endothelial growth factor expression in gastric cancer

AIM: To evaluate the expression of galectin-1 and vascular endothelial growth factor (VEGF) in gastric cancer and investigate their relationships with clinicopathologic factors and prognostic significance. METHODS: Galectin-1 and VEGF were immunohistochemically investigated in tumor samples obtained from 214 gastric cancer patients with all tumor stages. Immunohistochemical analyses for galectin-1 and VEGF expression were performed on formalin-fixed, paraffin-embedded sections of surgical specimens. The relationship between the expression and staining intensity of galectin-1 and VEGF, clinicopathologic variables, and patient survival were analyzed. All patients underwent follow-up until cancer-related death or more than five years after tumor resection. P values < 0.05 were considered statistically significant.RESULTS: Immunohistochemical staining demonstrated that 138 of 214 gastric cancer samples (64.5%) were positive for galectin-1, and 116 out of 214 gastric cancer samples (54.2%) were positive for VEGF. There was a significant association between galectin-1 and VEGF expression; VEGF was detected in 60.1% of galectin-1-positive samples and 43.4% of galectin-1-negative samples (P < 0.05). Galectin-1 expression was associated with tumor size, tumor location, stage, lymph node metastases, and VEGF expression (all P < 0.05). VEGF expression was related to tumor size, stage, and lymph node metastases (all P < 0.05). The 5-year survival rate was 56.6% for galectin-1-positive patients and 69.2% for galectin-1-negative patients, and the prognosis for galectin-1-positive patients was significantly poorer compared with galectin-1-negative patients (χ 2 = 13.880, P = 0.000). The 5-year survival rates for VEGF-positive and VEGF-negative patients were 53.4% and 70.5%, respectively (χ2 = 4.619, P = 0.032). The overall survival rate of patients with both galectin-1 and VEGF overexpression in gastric cancer tissue samples was significantly poorer than other groups (both P < 0.05).CONCLUSION: Galectin-1 expression was positively associated with VEGF expression. Both galectin-1 and VEGF can serve as independent prognostic indicators of poor survival for gastric cancer after gastrectomy.

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.

Vascular endothelial growth factor A, secreted in response to transforming growth factor-β1 under hypoxic conditions, induces autocrine effects on migration of prostate cancer cells

Hypoxia and transforming growth factor-β1 （TGF-β1） increase vascular endothelial growth factor A （VEGFA） expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-β1 was shown to induce VEGFA165 secretion from both normal cell lines （HPV7 and RWPE1） and prostate cancer cell lines （DU 145 and PC3）. Conversely, hypoxia-stimulated VEGFA165 secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-β1 expression in PC3 prostate cancer cells, and the TGF-β1 type I receptor （ALK5） kinase inhibitor partially blocked hypoxia-mediated VEGFA16s secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor （VEGFR） 1 （Fit-l） and 2 （FIk-I/KDR）. Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA165 treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERKI/2） in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA165 was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-β1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-β1 and hypoxia on metastatic prostate cancers.

STI571 (Glivec) suppresses the expression of vascular endothelial growth factor in the gastrointestinal stromal tumor cell line,GIST-T1

AIM： To estimate whether S-TI571 inhibits the expression of vascular endothelial growth factor （VEGF） in the gastrointestinal stromal tumor （GIST） cells. METHODS： We used GIST cell line, GIST-T1. It has a heterogenic 57-bp deletion in exon 11 to produce a mutated c-KIT, which results in constitutive activation of c-KIT. Cells were treated with/without STI571 or stem cell factor （SCF）. Transcription and expression of VEGF were determined by RT-PCR and flow cytometry or Western blotting, respectively. Activated c-KIT was estimated by immunoprecipitation analysis. Cell viability was determined by PITT assay. RESULTS： Activation of c-KIT was inhibited by STI571 treatment. VEGF was suppressed at both the transcriptional and translational levels in a temporal and dose-dependent manner by STI571. SCF upregulated the expression of VEGF and it was inhibited by S-13571. STI571 also reduced the cell viability of the GIST-T1 cells, as determined by PTT assay. CONCLUSION： Activation of c-KIT in the GIST-T1 regulated the expression of VEGF and it was inhibited by ST571. STI571 has antitumor effects on the GIST cells with respect to not only the inhibition of cell growth, but also the suppression of VEGF expression.

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 Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket

Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 （TGF-β1）, bone morphogenetic protein-2 （BMP-2） and vascular endothelial growth factor （VEGF） in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups （n=24）. Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket.

Interleukin-1α, 6 regulate the secretion of vascular endothelial growth factor A, C in pancreatic cancer

Vascular endothelial growth factor (VEGF, namely VEGF-A) is an angiogenic polypeptide and VEGF-C is a lymphangiogenic polypeptide that has been implicated in cancer growth, invasion and metastasis. Several cytokines and growth factors play an important part in cancer progression. These cytokines and growth factors are the principal mediators of cancer cells-stromal cell interaction , which is critical for invasion of cancer cells to the surrounding tissues and metastatic dissemination to distant organs. In this study, we studied VEGF-A, C expression in cultured human pancreatic cancer cell lines and whether the presence of VEGF-A, C in the cell lines is regulated by cytokines interleukin-lct (EL-1α), and interleukin-6 (IL-6). METHODS: We used Northern blot and Western blot methods to analyze expression of the gene and protein of VEGF-A, C in all 6 tested cell lines (ASPC-1, CAPAN-1, MIA-PaCa-2, PANC-1, COLO-357 and T3M4) respectively. To analyze what is the regulator for this VEGF-A, C expression in pancreatic cancer,we used the reverse transcription -polymerase chain reaction (RT-PCR) method to analyze VEGF-A, C expression in cultured human pancreatic cancer cell lines (CAPAN-1 and COLO-357) under the stimulation with IL-1α (10μg/L) or IL-6 (100 μg/L). RESULTS:Northern blot analysis revealed the presence of the 4.1-kb VEGF-A mRNA transcript and 2.4-kb VEGF-C mRNA transcript in all 6 tested cell lines. Immunoblotting with highly specific anti-VEGF-A, anti-VEGF-C antibody revealed the presence of a molecular weight of 43-kDa VEGF-A protein and 55-kDa VEGF-C protein in all the cell lines. RT-PCR analysis revealed the levels of the VEGF-A and VEGF-C gene were 1-2 fold and a 1-fold increase in the COLO-357 cell line by stimulation with IL-la, however, no effect was found in the CAPAN-1 cell line. The levels of the VEGF-A and VEGF-C gene were 2-5 fold and a 1-fold increase in the CAPAN-1 cell line by stimulation with IL-6, but, no effect was found in the COLO-357 cell line. CONCLUSION:These findings suggested that the expression of VEGF-A, C and their regulation by IL-1α, IL-6 in pancreatic cancer contributes to the lymphatic and distant metastasis and the disease progression.

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

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

Elevated levels of interleukin-1β, interleukin-6, tumor necrosis factor-α and vascular endothelial growth factor in patients with knee articular cartilage injury

BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of keen articular cartilage injury remains poorly understood. AIM To measure the levels of inflammatory factors [IL-1β, IL-6, TNF-α and VEGF] in patients with knee articular cartilage injury. METHODS Fifty-five patients with knee articular cartilage injury were selected as patient groups, who were divided into three grades [mild (n = 20), moderate (n = 19) and severe (n = 16)] according to disease severity and X-ray examinations. Meanwhile, 30 healthy individuals who underwent physical examination were selected as the control group. The levels of IL-1β, IL-6, TNF-α and VEGF were measured by ELISA and immunohistochemical staining. RESULTS Compared with the control group, patient groups displayed significantly higher levels of IL-1β, IL-6, TNF-α and VEGF, and the extent of increase was directly proportional to the severity of injury (P < 0.05). In addition, the number of cells with positive staining of IL-1β, IL-6, TNF-α and VEGF in the synovial membrane were significantly increased, along with increased disease severity (P < 0.05). After treatment, the scores of visual analogue scale and the Western Ontario and McMaster University of Orthopaedic Index in patient groups were 2.26 ± 1.13 and 15.56 ± 7.12 points, respectively, which were significantly lower than those before treatment (6.98 ± 1.32 and 49.48 ± 8.96). Correlation analysis suggested that IL-1β and TNF-α were positively correlated with VEGF. CONCLUSION IL-1β, IL-6, TNF-α and VEGF levels are increased in patients with knee articular cartilage injury, and are associated with the disease severity, indicating they might play an important role in the occurrence and development of knee articular cartilage injury. Furthermore, therapeutically targeting them might be a novel approach for the treatment of keen articular cartilage injury.

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

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

~1H-magnetic resonance spectroscopy of vascular endothelial growth factor-induced neuroprotection following acute cerebral ischemia and reperfusion

BACKGROUND： It has become generally accepted that measuring N-acetyl-L-aspartic acid through the use of 1H-magnetic resonance spectroscopy （1H-MRS） could be used to evaluate neuronal injury. OBJECTIVE： To study metabolic changes of N-acetyl-L-aspartic acid surrounding the acute cerebral ischemia area following vascular endothelial growth factor （VEGF） treatment using 1H-MRS imaging, and to evaluate the neuroprotective effects of VEGE DESIGN, TIME AND SETTING： Randomly controlled animal study, according to one-factor analysis of variance, was performed at the Shenzhen Hospital of Peking University and State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences from August 2003 to December 2005. MATERIALS： Twelve healthy, adult, Sprague Dawley rats were used to establish an ischemia/reperfusion model through the use of middle cerebral artery occlusion. The 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company. VEGF164 was purchased from Shenzhen Jingmei Bioengineering Co., Ltd. Titus anesthesia machine was purchased from Draeger Medical AG ＆ Co. KG METHODS： The rats were randomly divided into model control （n = 6） and VEGF-injected （n = 6） groups. All animals received 60-minute middle cerebral artery occlusion and 24-hour reperfusion. Lateral cerebral ventricle injection was performed by stereotaxic technique at respective time points. The VEGF group received 0.1 μg/μL L VEGF （5 μ L）, and the model group received the same amount of normal saline, once daily for 3 days. MAIN OUTCOME MEASURES： Metabolic changes of N-acetyl-L-aspartic acid and lactic acid following cerebral ischemia and reperfusion were detected using 1H-MRS, and the ischemic volume was measured. RESULTS： Twelve rats were included in the final analysis.1H-MRS results revealed that the ischemic volume increased in the control group compared with prior to injection （P 〈 0.01）. In the control group, the level of N-acetyl-L-aspartic acid decreased significantly at 7 days after injection （P 〈 0.01）, while lactic acid concentrations increased （P 〈 0.05）. In the VEGF group, the level of N-acetyl-L-aspartic acid decreased slightly, as well as lactic acid concentrations （P 〈 0.05）. CONCLUSION： By means of 1H-MRS, results demonstrated that lactic acid and N-acetyl-L-aspartic acid concentrations decreased following treatment with VEGE These results suggest that VEGF can provide prompt and safe neuroprotection following ischemic stroke.

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

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

Phosphatase and tensin homology deleted in chromosome 10,hypoxia-inducible factor-1 alpha gene expression in colorectal adenoma and adenocarcinoma and their relation to vascular endothelial growth factor protein expression

To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.

Expression of hypoxia-inducible factor la and vascular endothelial growth factor in hepatocellular carcinoma: Impact on neovascularization and survival

AIM: To study the expression of hypoxia-inducible factor 1α(HIF-1α) and vascular endothelial growth factor (VEGF) in hepatocellular carcinoma (HCC) and the impact on neovascularization and survival. METHODS: Expressions of HIF-1α, VEGF and microvessel density (MVD) are studied through immunohistochemistry in 36 cases of HCC and the corresponding paraneoplastic tissue and 6 cases of normal liver tissue. The relationship of the expressions of HIF-1α and VEGF with the clinicopathological data and survival are analyzed. RESULTS: The positive rate of VEGF in HCC was 32/36, which is significantly higher than that in paraneoplastic tissue and normal liver tissue (P<0.05). The expression of HIF-1aaaaaa in HCC tissue is 24/36, also higher than that in paraneoplastic tissue and normal liver tissue (P<0.05). The expression of VEGF and HIF-1α in HCC with microscopic venous invasion is significantly higher than that in HCC without microscopic venous invasion (P<0.05). Spearman correlation analysis does not only show the expression of HIF-1α as correlated with the expression of VEGF (rs = 0.459, P<0.01), but it also shows the expression of HIF-1α and VEGF as correlated with MVD (rs=0.412 and 0.336, respectively, P<0.05). The differences of the survival rates among VEGF positive group and VEGF negative group are significant (P<0.05), whereas the differences of the survival rates among the HIF-1α negative group and positive group are not significant (P>0.05). CONCLUSION: HIF-1α plays important roles in neovascularization in HCC possibly through regulation of VEGF transcription.

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.

Apelin and vascular endothelial growth factor are associated with mobilization of endothelial progenitor cells after acute myocardial infarction

This study was designed to determine the levels of early endothelial progenitor cells （EPCs）, apelin, vascu- lar endothelial growth factor （VEGF） and stromal cell-derived growth factor-1 （SDF-1） after acute myocardial infarction （AMI）, and to investigate the relationships between these cytokines and early EPCs. Early EPCs, de- fined as CD133＋, KDR＋, and CD34~ cells, were quantified by flow cytometry. The levels of early EPCs and those cytokines in AMI patients were significantly different from those with coronary artery disease or controls （P 〈 0.05）. Plasma apelin levels were inversely correlated with Gensini score and early EPCs （both P 〈 0.01）. Early EPCs, VEGF and SDF-1 showed different patterns of changes in AMI patients during the first 24 h. The trend in the change of early EPCs was proportionally correlated with that of VEGF （P 〈 0.05）. AMI patients exhibited in- creased early EPCs with remarkably decreased apelin levels and enhanced VEGF levels.