Hypoxia-inducible Vascular Endothelial Growth Factor Research Articles

Multifunctional Polymeric Nanosystems for Dual-Targeted Combinatorial Chemo/Angiogenesis Therapy of Tumors.

Combination of antiangiogenesis and chemotherapy holds vast promise for effective inhibition of tumor proliferation and invasion. Herein, a multifunctional self-assembled nanosystem consisting of amphiphilic c(RGDyK)-functionalized low-molecular-weight heparin-gambogic acid conjugate (cRHG) is developed, using c(RGDyK) peptide as αv β3 integrin targeting moiety to realize a double-targeted delivery to both tumor cells and angiogenic vasculature. cRHG with a markedly decreased anticoagulant activity can self-assemble into nanosized particles (around 150 nm). cRHG nanoparticles effectively inhibit vascular endothelial growth factor (VEGF)-triggered tube-like formation of HUVEC and neovascularization of subcutaneous Matrigel plugs. More importantly, the targeting ability of cRHG nanoparticles is revealed by their efficient internalization by αv β3 integrin-positive cells (U87MG and HUVEC) in vitro and obvious accumulation of Cy7/cRHG in the tumor site with strong fluorescence signals in both cancer cells and neovasculature. Besides, cRHG maintains the in vitro cytotoxic activity of gambogic acid, while achieving the highest in vivo antitumor activity in U87MG mouse xenograft model and displaying better safety profile than free drugs solutions. Mechanistic investigations reveal the substantial inhibition of hypoxia-inducible factor-1 alpha, VEGF, and CD31 expression by cRHG nanoparticles with remarkable down-regulation of VEGFR2 phosphorylation. These results suggest that cRHG nanoparticles provide a versatile nanoplatform for efficacious combinatorial tumor therapy.

Coffee induces vascular endothelial growth factor (VEGF) expression in human neuroblastama SH-SY5Y cells

Recent evidence indicates that hypoxia-inducible vascular endothelial growth factor (VEGF) has neurotrophic and neuroprotective effects on neuronal and glial cells. On the other hand, recent epidemiological studies showed that daily coffee consumption has been associated with a lower risk of several neuronal disorders. Therefore, we investigated the effect of coffee on VEGF expression in human neuroblastoma SH-SY5Y cells. We found that even low concentration of coffee (<2%) strongly induced VEGF expression via an activation of HIF-1α. The activation of HIF-1α by coffee was attributed to the coffee-dependent inhibition of prolyl hydroxylation of HIF1α, which is essential for proteolytic degradation of HIF-1α. However, no inhibition was observed at the catalytic activity in vitro. Coffee component(s) responsible for the activation of HIF-1α was not major constituents such as caffeine, caffeic acid, chlorogenic acid, and trigonelline, but was found to emerge during roasting process. The active component(s) was extractable with ethyl acetate. Our results suggest that daily consumption of coffee may induce VEGF expression in neuronal cells. This might be related to protective effect of coffee on neural disorders such as Alzheimer's disease and Parkinson's disease.

All-Trans Retinoic Acid Attenuates Hypoxia-Induced Injury in NRK52E Cells via Inhibiting NF-κB/VEGF and TGF-β2/VEGF Pathway

Background/Aims: Hypoxia has recently been proposed as one of the most important factors in progressive renal injury. Hypoxia-induced vascular endothelial growth factor (VEGF) expression may play a critical role in maintaining peritubular capillary endothelium in renal disease. This study was designed to investigate the effect and underlying mechanism of all-trans retinoic acid (ATRA) on hypoxia-induced injury in NRK52E cells. Methods: For mimicking hypoxia, cells were treated with 100 µM of cobalt chloride (CoCl2). The cell viability, expression of VEGF, p65, transforming growth factor-β2 (TGF-β2) and serine carboxypeptidase 1 (Scpep1), and nuclear factor of kappaB (NF-κB) activities after ATRA treatment were determined by MTT, western blot and electrophoretic mobility shift assay. Co-immunoprecipitation analysis was performed to demonstrate whether Scpep1 interacted with TGF-β2. Results: It was found that CoCl2 triggered hypoxia injury and significantly reduced cell viability. ATRA pretreatment increased the cell survival rate. Under hypoxic conditions, the expression of VEGF, p65 and TGF-β2 increased. Addition of ATRA significantly attenuated the expression of VEGF, p65 and TGF-β2. There was a corresponding variation of NF-κB/DNA binding activities. In addition, ATRA stimulated Scpep1 expression under normoxic and hypoxia condition. Furthermore, TGF-β2 interacted with Scpep1. Conclusions: This study indicated that ATRA may attenuate hypoxia-induced injury in NRK52E cells via inhibiting NF-κB/VEGF and TGF-β2/VEGF pathway.

Aromatic Hydrocarbon Receptor Suppresses Prostate Cancer Bone Metastasis Cells-Induced Vasculogenesis of Endothelial Progenitor Cells under Hypoxia

Background/Aims: Hypoxia leads to the development of neovascularization in solid tumor by regulating VEGF expression. Aromatic hydrocarbon receptor (AHR), a receptor for dioxin-like compounds, functions as a transcription factor through dimerization with hypoxia-inducible factors 1β (HIF-1β) and inhibits the secretion of vascular endothelial growth factor (VEGF). The purpose of this study was to explore whether AHR can suppress hypoxia-induced VEGF production in prostate bone metastasis cells and repress neovascularization in endothelial progenitor cells (EPCs), and, if so, through what mechanisms. Methods: PC-3 or LNCaP cells induced angiogenesis was detected by Matrigel-based tube formation assay, mRNA expression levels was measured by qRT-PCR, VEGF secretion level was determined by ELISA assay, respectively. Results: AHR activation inhibits hypoxia-induced adhesiveness and vasculogenesis of EPCs induced by PC-3 or LNCaP cells under hypoxia. Moreover, AHR activation suppressed hypoxia-induced VEGF production in PC-3 and LNCaP cells (48 ± 14% in PC-3, p = 0.000; 41 ± 14% in LNCaP, p = 0.000) by attenuating HIF-1α and HIF-1β level that in turn diminished the angiogenic ability of EPCs in vitro. Furthermore, we found the mRNA level of hypoxia-inducible factors 1α (HIF-1α) (1.54 ± 0.13 fold in PC-3, p = 0.002, 1.62 ± 0.12 fold in LNCaP, p = 0.001) and HIF-1β (1.67 ± 0.23 fold in PC-3, p = 0.007; 1.75 ± 0.26 fold in LNCaP, p=0.008) were upregulated in prostate cancer bone metastasis PC-3 and LNCaP cell lines in response to hypoxia, and revealed that the regulation of VEGF by HIF-1α and HIF-1β was possibly mediated by the activation of phosphatidylinositol 3-kinase pathway. Conclusion: By providing a mechanistic insight into the modulation of neovascularization by AHR ligand, we suggest that AHR ligand has a strong potential of being a new therapeutic agent with applications in the field of bone metastatic prostate cancer.

Sulforaphane inhibits hypoxia-induced HIF-1α and VEGF expression and migration of human colon cancer cells.

The effects of sulforaphane (a natural product commonly found in broccoli) was investigated on hypoxia inducible factor-1α (HIF-1α) expression in HCT116 human colon cancer cells and AGS human gastric cancer cells. We found that hypoxia-induced HIF-1α protein expression in HCT116 and AGS cells, while treatment with sulforaphane markedly and concentration-dependently inhibited HIF-1α expression in both cell lines. Treatment with sulforaphane inhibited hypoxia-induced vascular endothelial growth factor (VEGF) expression in HCT116 cells. Treatment with sulforaphane modulated the effect of hypoxia on HIF-1α stability. However, degradation of HIF-1α by sulforaphane was not mediated through the 26S proteasome pathway. We also found that the inhibition of HIF-1α by sulforaphane was not mediated through AKT and extracellular signal-regulated kinase phosphorylation under hypoxic conditions. Finally, hypoxia-induced HCT116 cell migration was inhibited by sulforaphane. These data suggest that sulforaphane may inhibit human colon cancer progression and cancer cell angiogenesis by inhibiting HIF-1α and VEGF expression. Taken together, these results indicate that sulforaphane is a new and potent chemopreventive drug candidate for treating patients with human colon cancer.

Natriuretic peptides, via GC-A/cGMP, moderate hypoxia-induced VEGF release from astrocytes and thereby pathological neovascularization in the retina

Background Our previous studies demonstrated that natriuretic peptides, i.e. BNP produced by activated satellite cells within ischemic skeletal muscle, stimulate the regeneration of neighboring endothelia via endothelial GC-A/ cGMP signaling [1]. This paracrine communication might be critically involved in coordinating postischemic muscle regeneration and angiogenesis. In the retina, angiogenesis occurs as a part of normal development as well as in proliferative vascular diseases, such as diabetic retinopathy (DR) or retinopathy of prematurity (ROP) [2]. Retinal vascular development is controlled by interactions between ganglion cells, astrocytes and endothelial cells. In particular, reciprocal feedback between endothelial cells and astrocytes is crucial for proper vascular patterning. Hypoxia-induced vascular endothelial growth factor (VEGF) expression in astrocytes plays a key role in (patho)physiological retinal endothelial growth. Notably, immunohistochemistry on postnatal (P7) retinal whole-mounts revealed the expression of immunoreactive BNP in glial fibrillary acidic protein (GFAP)–expressing astrocytes. Therefore we postulated that BNP participates in this astrocyte-endothelial communication during physiological vascularization and/or pathological revascularization of the retina.

Low Molecular Weight Fucoidan Inhibits Tumor Angiogenesis through Downregulation of HIF-1/VEGF Signaling under Hypoxia.

Activation of hypoxia-induced hypoxia-inducible factors-1 (HIF-1) plays a critical role in promoting tumor angiogenesis, growth and metastasis. Low molecular weight fucoidan (LMWF) is prepared from brown algae, and exhibits anticancer activity. However, whether LMWF attenuates hypoxia-induced angiogenesis in bladder cancer cells and the molecular mechanisms involved remain unclear. This is the first study to demonstrate that LMWF can inhibit hypoxia-stimulated H2O2 formation, HIF-1 accumulation and transcriptional activity vascular endothelial growth factor (VEGF) secretion, and the migration and invasion in hypoxic human bladder cancer cells (T24) cells. LMWF also downregulated hypoxia-activated phosphorylation of PI3K/AKT/mTOR/p70S6K/4EBP-1 signaling in T24 cells. Blocking PI3K/AKT or mTOR activity strongly diminished hypoxia-induced HIF-1α expression and VEGF secretion in T24 cells, supporting the involvement of PI3K/AKT/mTOR in the induction of HIF-1α and VEGF. Additionally, LMWF significantly attenuated angiogenesis in vitro and in vivo evidenced by reduction of tube formation of hypoxic human umbilical vascular endothelial cells and blood capillary generation in the tumor. Similarly, administration of LMWF also inhibited the HIF-1α and VEGF expression in vivo, accompanied by a reduction of tumor growth. In summary, under hypoxia conditions, the antiangiogenic activity of LMWF in bladder cancer may be associated with suppressing HIF-1/VEGF-regulated signaling pathway.

Regulatory mechanism of Siah1 in the pathogenesis of rat hypoxic pulmonary hypertension

To explore the regulatory mechanism of Siahl in the pathogenesis of hypoxic pulmonary hypertension (HPH) in rats. According to the random number table, 40 adult male Wistar rats were randomly divided into 5 groups (n = 8 each). And the animals were exposed to normoxia or hypoxia for 3, 7, 14 or 21 days respectively. The HPH model was established by normobaric intermittent hypoxia. Mean pulmonary arterial pressure (mPAP), ratio of vascular wall area to total vascular area (WA%), ratio of vascular lumen area to total vascular area (LA%) and right ventricle hypertrophy index (RVHI) were measured. The mRNA and protein relative levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were detected by in situ hybridization and immunohistochemistry respectively. Reverse transcriptase-polymerase chain reaction ( RT-PCR) and in situ hybridization were used to determine the relative expressions of mRNA of hypoxia-inducible factor-1 (FIH) and Siahl. Immunohistochemistry and Western blot were employed to determine the relative expressions of proteins of FIH and Siahl. The levels of mPAP, WA% and LA% were significantly higher after 7-day hypoxia than those in normoxic control (21. 3 1. 6) vs (15. 9 ± 1. 3) mmHg (1 mmHg = 0. 133 kPa), (41.4 ± 2.8)% vs (35.0 ± 2.2)%, (58.6 ± 2.8)% vs (65.0 ± 2.2)%, all P <0.05). The level of RVHI was significantly higher after 14-day hypoxia than that in normoxic control ((27. 0 ± 1. 8) % vs (3. 2 ± 2. 1) %, P <0. 05). The relative expression of HIF-1α mRNA was significantly higher after 14-day hypoxia than that in normoxic control (0. 188 ± 0. 014 vs 0. 150 ± 0. 014, P < 0. 05). The relative expression of HIF-1α protein was significantly higher after 3-day hypoxia than that in normoxic control (0. 186 ± 0.014 vs 0. 067 ± 0.008, P <0.05). The relative levels of VEGF mRNA and protein were significantly higher after 7-day hypoxia than those in normoxic control (0. 152 ± 0. 019 vs 0. 057 ± 0. 007, 0. 176 ± 0. 017 vs 0. 083 ± 0. 010, both P <0. 05). The relative expression of FIH mRNA had little changes after exposure to hypoxia compared with normoxia. However the related expression of FIH protein was markedly lower after 7-day hypoxia than that in normoxic control (0. 166 ± 0. 015 vs 0. 200 ± 0. 017, P < 0. 05). The relative levels of Siahl mRNA and protein were markedly higher after 7-day hypoxia than those in normoxic control (0. 144 ± 0. 014 vs 0. 067 ± 0. 010, 0. 136 ± 0. 017 vs 0. 084 ± 0. 019, both P <0. 05). Linear correlation analysis showed that HIF-1α protein was positively correlated with the relative levels of VEGF mRNA and VEGF protein (r = 0. 545, 0. 523, both P <0. 01) while FIH protein was negatively correlated with the relative levels of VEGF mRNA and VEGF protein (r = -0. 785, -0. 788, both P < 0. 01). There was a positive correlation between the relative levels of Siahi mRNA and Siahl protein (r = 0. 823, P <0. 01) while a negative correlation existed between the relative levels of Siahl protein and FIH protein (r = -0. 671, P <0. 01). Under chronic hypoxia, Siahl is transcriptionally induced in pulmonary arterioles and it facilitates the degradation and decline of FIR in rats. And deceased FIH protein in pulmonary arterioles under hypoxia may attenuate its inhibitory effect on the transactivational activity of HIF-l a and promote the transactivation of such HIF-1α target gene as VEGF. Thus it is probably implicated in the pathogenesis of HPH.

The research on the formation mechanism of extraordinary oxidative capacity of skeletal muscle in hibernating ground squirrels (Spermophilus dauricus).

Previous studies indicate that hibernating animals, under conditions of torpor for long periods, show an increased oxidative muscle fibers (type I) ratio and a decreased glycolytic muscle fibers (type II) ratio in skeletal muscle and accompanied by extraordinary oxidative ability. This observation is completely contrasted with non-hibernators, which show a shift of oxidative muscle fibers (type I) to glycolytic muscle fibers (type II). Presently, the mechanisms by which these changes occur remain unclear. To investigate the mechanism of high oxidative capacity of the skeletal muscles in hibernating ground squirrels, capillary density (CD), and capillary/fiber (C/F) were measured by immunohistochemistry. mRNA expression levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were determined using real-time quantitative PCR assay. Spectrophotometry was applied to determine the activities of hexokinase (PK), pyruvate kinase (HK), and cytochrome c oxidase (CcO). Inthe soleus muscle (SOL), mRNA expression levels of HIF-1αandVEGF in torpor became slightly lower but were not statistically significant; they were, however, significantly higher in the arousal group. In hibernating animals, no significant change occurred in CD but C/F increased by 15 %. CcO showed the highest activity in torpor. There were no significant differences in the activities of HK and PK between the torpid animals and summer active animals in SOL. However, PK activity increased by 34 % after hibernation. Oxidative capacitymay be ensured by an increase of capillary supply of skeletal muscle in hibernating animals.

Overexpression of hypoxia-inducible factor prolyl hydoxylase-2 attenuates hypoxia-induced vascular endothelial growth factor expression in luteal cells.

Vascular endothelial growth factor (VEGF)-dependent angiogenesis has a crucial role in the corpus luteum formation and their functional maintenances in mammalian ovaries. A previous study by our group reported that activation of hypoxia‑inducible factor (HIF)‑1α signaling contributes to the regulation of VEGF expression in the luteal cells (LCs) in response to hypoxia and human chorionic gonadotropin. The present study was designed to test the hypothesis that HIF prolyl‑hydroxylases (PHDs) are expressed in LCs and overexpression of PHD2 attenuates the expression of VEGF induced by hypoxia in LCs. PHD2-overexpressing plasmid was transfected into LC2 cells, and successful plasmid transfection and expression was confirmed by reverse transcription quantitative polymerase chain reaction and western blot analysis. In addition, the present study investigated changes of HIF‑1α and VEGF expression after incubation under hypoxic conditions and PHD2 transfection. PHD2 expression was significantly higher expressed than the other two PHD isoforms, indicating its major role in LCs. Moreover, a significant increase of VEGF mRNA expression was identified after incubation under hypoxic conditions, which was, however, attenuated by PHD2 overexpression in LCs. Further analysis also indicated that this hypoxia‑induced increase in the mRNA expression of VEGF was consistent with increases in the protein levels of HIF‑1α, which is regulated by PHD-mediated degradation. In conclusion, the results of the present study indicated that PHD2 is the main PHD expressed in LCs and hypoxia‑induced VEGF expression can be attenuated by PHD2 overexpression through HIF‑1α‑mediated mechanisms in LCs. This PHD2-mediated transcriptional activation may be one of the mechanisms regulating VEGF expression in LCs during mammalian corpus luteum development.

Abstract 639: Carnosine Supplementation Promotes Revascularization in Mouse model of Hindlimb Ischemia

Revascularization surgeries are important for treatment of critical limb ischemia (CLI) however, advanced CLI patients are poor candidates for these surgeries. Here, we proposed that carnosine, a dipeptide of β-alanine and histidine which is highly abundant in the skeletal muscle (2-20mM) and has the abilities to quench reactive aldehydes and chelate divalent metals, can promote revascularization. WTC57Bl/6 mice were pre-treated with carnosine (1g/L) in drinking water for 7 days, subjected to hindlimb ischemia surgery (HLI) by femoral artery ligation and allowed to recover for 14 days with carnosine supplementation. Doppler analysis showed that carnosine supplementation increased blood perfusion to 63±6% compared to 19±3% in controls. Post-surgery carnosine treatment also increased blood flow to 49.4± 6% compared to 28.2± 4% in controls following 21 days of recovery. Histological analysis of the ischemic limb showed that tissue injury was attenuated by carnosine supplementation. Mobilization of angiogenic endothelial progenitor cells (EPCs) (Flk+/Sca+) and the expression of vascular endothelial growth factor (VEGF) in the ischemic muscle was enhanced by carnosine treatment. These results were associated with an increase in ischemic muscle carnosine levels in the carnosine treated HLI mice. Furthermore, expression of the carnosine transporter PHT1 was increased in carnosine treated HLI mice compared to HLI mice. Concomitant with the increased VEGF expression in carnosine treated HLI mice, we observed that pre-treatment of murine myoblast C2C12 cells with octyl-D-carnosine followed by hypoxia increased hypoxia inducible factor 1-alpha nuclear translocation and VEGF expression and secretion. Our results demonstrate that carnosine treatment increases blood flow in the ischemic limb by increasing EPC mobilization and therefore can be a potential therapeutic intervention for CLI patients.

Regulation of Hypoxia-inducible Factor-1α and Vascular Endothelial Growth Factor Signaling by Plant Flavonoids.

Discovery of novel drugs that are able to prevent angiogenesis is a fast growing branch of cancer research. Current approaches to cancer chemotherapy include the use of alkylating agents, antimetabolites, antitumor antibiotics, platinum analogs and drugs derived from natural compounds. However, most of the currently used chemotherapeutic drugs have adverse side effects on normal healthy cells. In addition to the classical targets of cancer chemotherapy, prevention of angiogenesis through the regulation of indigenous angiogenic factors is a leading approach of developing selective novel anticancer drugs. Because of their low toxicity, there is increasing interest in exploring specific dietary phytochemicals as possible antiangiogenic agents. In this mini-review, selected flavonoids (e.g., apigenin, luteolin, quercetin and epigallocatechin-3-gallate, which are a group of plant polyphenols) that are able to regulate angiogenesis in in vitro and in vivo systems are discussed in the light of their potential to be exploited as novel anticancer drugs.

Retinal hypoxia induces vascular endothelial growth factor through induction of estrogen-related receptor γ

Ischemic retinopathies causing overexpression of pro-angiogenic factors, including vascular endothelial growth factor (VEGF), are the most common cause of blindness. Thus, understanding the pathophysiology of targetable pathways that regulate retinal VEGF is of great interest. A conserved binding site for estrogen-related receptor γ (ERRγ) has been identified in the promoter of the Vegfa gene. ERRγ is a constitutively active orphan nuclear receptor and its expression is increased by hypoxic stimuli in metabolically active tissues. This study evaluated the role of ERRγ in the ischemic retina and the anti-VEGF potential of GSK5182, a selective inverse agonist of ERRγ. In an oxygen-induced retinopathy (OIR) mouse model, immunohistochemistry showed significantly increased ERRγ expression in the ganglion cell layer at postnatal day (P) 17. In a ganglion cell line (RGC-5), mRNA and protein levels of ERRγ were increased by desferrioxamine treatment and hypoxic conditions (1% O2). Transient transfection of RGC-5 cells revealed that ERRγ regulated Vegfa expression and this was inhibited by GSK5182. Intravitreal injection of GSK5182 into the OIR model at P14 inhibited retinal Vegfa mRNA expression at P17. GSK5182 suppresses hypoxia-induced VEGF expression via ERRγ; therefore, ERRγ could be a treatment target for ischemic retinopathies.

Resveratrol Inhibits Hypoxia-Induced Vascular Endothelial Growth Factor Expression and Pathological Neovascularization.

PurposeTo investigate the effects of resveratrol on the expression of hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) in human adult retinal pigment epithelial (ARPE-19) cells, and on experimental choroidal neovascularization (CNV) in mice.Materials and MethodsARPE-19 cells were treated with different concentrations of resveratrol and then incubated under hypoxic conditions with subsequent evaluation of cell viability, expression of HIF-1α, and expression of VEGF. The effects of resveratrol on the synthesis and degradation of hypoxia-induced HIF-1α were evaluated using inhibitors of the PI3K/Akt/mTOR and the ubiquitin proteasome pathways. In animal studies, CNV lesions were induced in C57BL/6 mice by laser photocoagulation. After 7 days of oral administration of resveratrol or vehicle, which began one day after CNV induction, image analysis was used to measure CNV areas on choroidal flat mounts stained with isolectin IB4.ResultsIn ARPE-19 cells, resveratrol significantly inhibited HIF-1α and VEGF in a dose-dependent manner, by blocking the PI3K/Akt/mTOR signaling pathway and by promoting proteasomal HIF-1α degradation. In mice experiments, orally administered resveratrol significantly inhibited CNV growth in a dose-dependent manner.ConclusionResveratrol may have therapeutic value in the management of diseases involving pathological neovascularization.

Thymosin Beta-4, Actin-Sequestering Protein Regulates Vascular Endothelial Growth Factor Expression via Hypoxia-Inducible Nitric Oxide Production in HeLa Cervical Cancer Cells

Vascular endothelial growth factor (VEGF) is an important regulator of neovascularization. Hypoxia inducible nitric oxide (NO) enhanced the expression of VEGF and thymosin beta-4 (Tβ4), actin sequestering protein. Here, we investigated whether NO-mediated VEGF expression could be regulated by Tβ4 expression in HeLa cervical cancer cells. Hypoxia inducible NO production and VEGF expression were reduced by small interference (si) RNA of Tβ4. Hypoxia response element (HRE)-luciferase activity and VEGF expression were increased by the treatment with N-(β-D-Glucopyranosyl)-N2-acetyl-S-nitroso-D, L-penicillaminamide (SNAP-1), to generate NO, which was inhibited by the inhibition of Tβ4 expression with Tβ4-siRNA. In hypoxic condition, HRE-luciferase activity and VEGF expression were inhibited by the treatment with NG-monomethyl-L-arginine (L-NMMA), an inhibitor to nitric oxide synthase (NOS), which is accompanied with a decrease in Tβ4 expression. VEGF expression inhibited by L-NMMA treatment was restored by the transfection with pCMV-Tβ4 plasmids for Tβ4 overexpression. Taken together, these results suggest that Tβ4 could be a regulator for the expression of VEGF via the maintenance of NOS activity.

Influence of paclitaxel on the correlation factors in serum and tissue of patients with metrocarcinoma

Objective To explore the level of hypoxia-inducible factor-1α（ HIF-1α） and vascular endotheli-al growth factor（ VEGF） in serum and tissue of patients with metrocarcinoma.Methods 48 patients diagnosed with cervical cancer were analyzed retrospectively.Patients were treated with paclitaxel combination chemotherapy,HIF-1αand VEGF levels in serum of patients were detected by ELISA method before and after the treatment.HIF-1αand VEGF levels in cervical tissue of patients were observed by immunehistochemical staining methods.Western blot method was used to detect the change of HIF-1αand VEGF expression levels in cervical tissues of patients.And the levels of HIF-1αand VEGF in patients with lymphatic metastasis and lymph node metastases were compared. Results Lymph node metastasis did not occur in patients with uterine cancer serum HIF-1αand VEGF were （16.71 ±34.75）ng/L,（255.77 ±87.99）ng/L,respectively,and those after treatment were （98.33 ±32.17）ng/L, （153.67 ±65.45）ng/L,the differences were statistically significant（t=9.416,5.001,P=0.003,0.007） before and after treatment;The serum of patients with lymph node metastasis of uterine cancer in HIF-1αand VEGF increased, and cervical cancer patients after treatment,cervical tissue HIF-1αand VEGF;The metastasis were statistically signif-icant differences occurred（t=3.055,16.196,P=0.038,0.000）;HIF-1αand VEGF decreased after treatment,the expression levels were significantly decreased compared with before treatment （ t=5.899,P=0.004;t=9.649,P=0.001）;patients with lymph node metastasis after treatment,the expression levels of HIF-1αdecreased compared with before treatmen （ t =5.233, P =0.004）, but there was no significant changes in the expression of VEGF. Conclusion The mechanism of taxol anti-uterine cancer may be related with inhibition the expression of HIF-1αand VEGF protein,and thereby inhibiting tumor angiogenesis and cancer metastasis. Key words: Paclitaxel Uterine Neoplasms Hypoxia-Inducible Factor 1; alpha Subunit Vascular Endothelial Growth Factors

S222: Investigation of prostatic hypoxia-inducible factor-1 alfa and vascular endothelial growth factor expression in patients recieving dutasteride

S222: Investigation of prostatic hypoxia-inducible factor-1 alfa and vascular endothelial growth factor expression in patients recieving dutasteride

Ginsenoside Rg3 attenuates hepatoma VEGF overexpression after hepatic artery embolization in an orthotopic transplantation hepatocellular carcinoma rat model.

BackgroundHypoxia-induced vascular endothelial growth factor (VEGF) upregulation and angiogenesis following treatment of hepatocellular carcinoma (HCC) with transarterial embolization (TAE) or transarterial chemoembolization (TACE) may be mediated by ginsenoside Rg3, an anti-angiogenic saponin extracted from ginseng.ObjectiveTo access the synergistic action of Rg3 and TAE treatment on HCC by VEGF and it’s receptor expressions decreasing in a rat model of HCC.MethodsAn orthotopic transplantation HCC model was established in Buffalo rats. HCC rats were treated with hepatic artery infusions of normal saline or iodized oil (0.1 mL) with or without Rg3 (1 mg/kg) (each n=15 in control, Rg3, TAE, and TAE + Rg3 groups). At 1, 2, 4, and 8 weeks, performance status (body weight), tumor progression (longest tumor diameter), metastasis rate, microvessel density (MVD), and overall survival rate were assessed. Additionally, cluster of differentiation 31 (CD31), VEGF, VEGF receptor 2 (VEGF-R2) and VEGF-R2 phosphorylation levels were assessed by immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), and Western blot.ResultsCombined Rg3 and TAE treatment reduced tumor progression, body weight loss, angiogenesis, and metastasis rate, and led to better overall survival in the HCC rat model. ELISA results showing VEGF expression in the control, Rg3, TAE, and TAE + Rg3 groups at 4 weeks following treatment were 132.6±2.38, 37.9±0.8, 87.4±0.7, and 45.3±0.4 pg/mL, respectively. Combined Rg3 and TAE reduced the protein expression of CD31 and VEGF-R2 phosphorylation, compared with those in the TAE group at 4 weeks of treatment.ConclusionCombined Rg3 and TAE treatment limited metastasis and promoted survival by downregulating VEGF overexpression in HCC tumors. Thus, this treatment may have potential clinical implications for HCC patients undergoing TAE or TACE.

Effect of PGN stimulation on hypoxia-induced VEGF expression in RASF

Objective To investigate the effect of peptidoglycan (PGN) on the expression of hypoxia-inducible factor-1 α (HIF-1 α) and vascular endothelial growth factor (VEGF) in rheumatoid arthritis synovial fibroblast (RASF) induced by hypoxia.Methods RASF were isolated from 6 cases of rheumatoid arthritis (RA) and cultured in vitro,then divided into control group,CoCl2 group,PGN group and CoCl2 + PGN group.The mRNA level of HIF-1 α was detected by qRT-PCR and then the protein level of VEGF was tested by ELISA before and after silencing HIF-1 α.Results The expression of HIF-1 α and VEGF was upregulated in RASF induced by CoCl2 compared to control (P ＜ 0.05).PGN potentiated the levels of HIF-1 α and VEGF in RASF treated by CoCl2 (P ＜ 0.05).Silencing HIF-1 α decreased PGN and hypoxia-augmented VEGF production (P ＜ 0.05).Conclusion Activation of TLR2 signaling can enhance the levels of HIF-1 α and VEGF in RASF under hypoxia environment,and interfereing of HIF-1 α may be an effective therapeutic strategy for RA. Key words: Hypoxia; Hypoxia-inducible factor 1α ; Synovial fibroblasts; Vascular endothelial growth factor; Rheumatoid arthritis

Molecular imaging of expression of vascular endothelial growth factor a (VEGF a) in femoral bone grafts transplanted into living mice.

The biology of cells transplanted with bone grafts is incompletely understood. Focusing on the early angiogenic response postgrafting, we report a mouse femur graft model in which grafts were derived from mice transgenic for a firefly luciferase (FLuc) bioluminescence reporter gene driven by a promoter for the angiogenic signaling molecule vascular endothelial growth factor (VEGF). Upon transplantation into wild-type (wt) mice, in vivo bioluminescence imaging (BLI) permitted longitudinal visualization and measurements of VEGF promoter activity in the transplanted graft cells and demonstrated a lag period of 7 days posttransplantation prior to robust induction of the promoter. To determine cellular mediators of VEGF induction in graft bone, primary graft-derived osteoblastic cells (GDOsts) were characterized. In vitro BLI on GDOsts showed hypoxia-induced VEGF expression and that this induction depended on PI3K signaling and, to a lesser degree, on the MEK pathway. This transcriptional regulation correlated with VEGF protein production and was validated in GDOsts seeded on demineralized bone matrix (DBM), a bone graft substitute material. Together, combined imaging of VEGF expression in living animals and in live cells provided clues about the regulation of VEGF in cells post-bone grafting. These data are particularly significant toward the development of future smart bone graft substitutes.