TROVE2 regulated invasion and migration of hepatocellular carcinoma cells via heparanase

Background:The role of TROVE domain family member 2(TROVE2)has been well-demonstrated in autoimmune diseases;however,its involvement in liver cancer remains unclear.Therefore,this study aimed to explore the biological function and clinical significance of TROVE2 in hepatocellular carcinoma(HCC).Methods:The expression level of TROVE2 was analyzed in HCC and paired adjacent tissue samples using real-time reverse transcription-quantitative polymerase chain reaction.The impact of TROVE2 on migration and invasion in HCC cells was analyzed through Transwell assays and Western blotting.High-throughput transcriptome sequencing and bioinformatics analyses were performed to identify downstream target genes.Back-complementation experiments were employed to verify the influence of downstream proteins on TROVE2-induced invasion and migration of HCC cells.Results:TROVE2 exhibited significant overexpression in liver cancer tissue,correlating with shorter overall survival.Overexpression of TROVE2 facilitated the invasion,metastasis,and epithelial-mesenchymal transition(EMT)process of HCC cells,whereas TROVE2 knockdown restrained migration,invasion,and EMT in these cells.Transcriptome sequencing and bioinformatics analysis identified heparanase(HPSE)as a downstreamtarget protein of TROVE2.Subsequent back-complementation experiments provided evidence that HPSE overexpression promoted TROVE2-mediated prometastasis effects.Moreover,the study revealed that TROVE2 was capable of regulating the EMT pathway through GSK-3βphosphorylation.Conclusions:TROVE2 facilitated the invasion,migration,and EMT process ofHCC cells through phosphorylation of the HPSE/GSK-3βaxis,indicating its significance as an important protein in tumor progression.

Heparanase inhibition leads to improvement in patients with acute gastrointestinal injuries induced by sepsis

BACKGROUND Patients with sepsis are at high risk for acute gastrointestinal injury(AGI),but the diagnosis and treatment of AGI due to sepsis are unsatisfactory.Heparanase(HPA)plays an important role in septic AGI(S-AGI),but its specific mechanism is not completely understood,and few clinical reports are available.AIM To explore the effect and mechanism of HPA inhibition in S-AGI patients.METHODS In our prospective clinical trial,48 patients with S-AGI were randomly assigned to a control group to receive conventional treatment,whereas 47 patients were randomly assigned to an intervention group to receive conventional treatment combined with low molecular weight heparin.AGI grade,sequential organ failure assessment score,acute physiology and chronic health evaluation II score,D-dimer,activated partial thromboplastin time(APTT),anti-Xa factor,interleukin-6,tumour necrosis factor-α,HPA,syndecan-1(SDC-1),LC3B(autophagy marker),intestinal fatty acid binding protein,D-lactate,motilin,gastrin,CD4/CD8,length of intensive care unit(ICU)stay,length of hospital stay and 28-d survival on the 1^(st),3^(rd) and 7^(th) d after treatment were compared.Correlations between HPA and AGI grading as well as LC3B were compared.Receiver operator characteristic(ROC)curves were generated to evaluate the diagnostic value of HPA,intestinal fatty acid binding protein and D-lactate in S-AGI.RESULTS Serum HPA and SCD-1 levels were significantly reduced in the intervention group compared with the control group(P<0.05).In addition,intestinal fatty acid-binding protein,D-lactate,AGI grade,motilin,and gastrin levels and sequential organ failure assessment score were significantly decreased(P<0.05)in the intervention group.However,LC3B,APTT,anti-Xa factor,and CD4/CD8 were significantly increased(P<0.05)in the intervention group.No significant differences in interleukin-6,tumour necrosis factor-α,d-dimer,acute physiology and chronic health evaluation II score,length of ICU stay,length of hospital stay,or 28-d survival were noted between the two groups(P>0.05).Correlation analysis revealed a significant negative correlation between HPA and LC3B and a significant positive correlation between HPA and AGI grade.ROC curve analysis showed that HPA had higher specificity and sensitivity in diagnosis of S-AGI.CONCLUSION HPA has great potential as a diagnostic marker for S-AGI.Inhibition of HPA activity reduces SDC-1 shedding and alleviates S-AGI symptoms.The inhibitory effect of HPA in gastrointestinal protection may be achieved by enhanced autophagy.

人Heparanase基因真核和原核表达载体的构建及融合蛋白的表达

目的 :构建人Heparanase基因的真核、原核表达载体 ,大肠杆菌表达其融合蛋白 .方法 :采用反转录 聚合酶链反应从人肝癌细胞株HepG2cDNA中 ,分别扩增出Heparanase编码基因 ,用限制性内切酶BamHI消化后 ,插入真核表达载体pcDNA3.1中 ,经酶切鉴定与测序证实后 ,连接成包括完整的人Heparanase基因ORF区的真核表达载体 .以亚克隆法构建于原核表达载体pRSET的相应酶切位点 ,转化大肠杆菌BL2 1菌株 ,异丙基 β D硫代半乳糖苷 (IPTG)诱导产生融合蛋白 .结果 :构建的人Heparanase基因表达载体经序列测定证实 ,与GenBank登录结果完全一致 ;双酶切鉴定证实 ,克隆基因正确插入载体pcDNA3.1及pRSET ;SDS PAGE证实融合蛋白表达成功 .结论 :成功构建了人Heparanase基因真核、原核表达载体 ,成功正确表达了

Heparanase与bFGF在膀胱移行细胞癌中的表达研究

目的探讨类肝素酶(heparanase,Hpa)与碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)在膀胱移行细胞癌(transitional cell carcinoma of the bladder,TCCB)发生、发展中的作用及意义。方法应用免疫组织化学S-P法,检测69例BTCC和9例正常膀胱组织中Hpa和bFGF的表达。结果膀胱癌中,Hpa阳性表达率为42.03%;bFGF阳性表达率为44.93%;Hpa与bFGF共表达阳性率为31.89%;9例正常膀胱黏膜中均未见Hpa和bFGF阳性表达。Hpa与bFGF表达均随着膀胱癌病理分级和临床分期的升高而增强(P<0.05)。结论Hpa与bFGF可能作为预测膀胱移行细胞癌进展的指标及肿瘤治疗靶点,并有可能成为一个有效的预后指标。

Helicobacter pylori promotes invasion and metastasis of gastric cancer by enhancing heparanase expression

AIM To detect the mechanisms of Helicobacter pylori(H. pylori) infection in the invasion and metastasis of gastric cancer(GC).METHODS Specimens from 99 patients with GC were collected. The correlation among H. pylori infection, heparanase(HPA) and mitogen-activated protein kinase(MAPK) expression, which was determined by immunohistochemistry, and the clinical features of GC was analysed using SPSS 22.0. Overall survival(OS) and relapse-free survival(RFS) of GC patients were estimated by the KaplanMeier method. Independent and multiple factors of HPA and MAPK with prognosis were determined with COX proportional hazards models. HPA and MAPK expression in MKN-45 cells infected with H. pylori was analysed using Western blot. RESULTS H. pylori infection was observed in 70 of 99 patients with GC(70.7%), which was significantly higher than that in healthy controls. H. pylori infection was related to lymph metastasis and expression of HPA and MAPK(P < 0.05); HPA expression was relevant to MAPK expression(P = 0.024). HPA and MAPK expression in MKN-45 cells was significantly upregulated following H. pylori infection and peaked at 24 h and 60 min, before decreasing(P < 0.05). SB203580, an inhibitor of MAPK, significantly decreased HPA expression. HPA was related to lymph metastasis and invasive depth. HPA positive GC cases and H. pylori positive GC cases showed poorer prognosis than HPA negative cases(P < 0.05). COX models showed that the prognosis of GC was connected with HPA expression, lymph metastasis, tissue differentiation, and invasive depth. CONCLUSION H. pylori may promote the invasion and metastasis of GC by increasing HPA expression that may associate with MAPK activation, thus causing a poorer prognosis of GC.

Heparanase and hepatocellular carcinoma:Promoter or inhibitor?

Heparan sulphate proteoglycans (HSPGs) consist of a core protein and several heparan sulphate (HS) side chains covalently linked. HS also binds a great deal of growth factors, chemokines, cytokines and enzymes to the extracellular matrix and cell surface. Heparanase can specially cleave HS side chains from HSPGs. There are a lot of conflicting reports about the role of heparanase in hepatocellular carcinoma (HCC). Heparanase is involved in hepatitis B virus infection and hepatitis C virus infection, the activation of signal pathways, metastasis and apoptosis of HCC. Heparanase is synthesized as an inactive precursor within late endosomes and lysosomes. Then heparanase undergoes proteolytic cleavage to form an active enzyme in lysosomes. Active heparanase translocates to the nucleus, cell surface or extracellular matrix. Different locations of heparanase may exert different activities on tumor progression. Furthermore, enzymatic activities and non-enzymatic activities of heparanase may play different roles during HCC development. The expression level of heparanase may also contribute to the discrepant effects of heparanase. Growth promoting as well as growth inhibiting sequences are contained within the tumor cell surface heparan sulfate. Degrading different HSPGs by heparanase may play different roles in HCC. Systemic studies examining the processing, expression, localization and function of heparanase should shed a light on the role of heparanase in HCC.

Targeted Silencing of Heparanase Gene by Small Interfering RNA Inhibits Invasiveness and Metastasis of Osteosarcoma Cells

The effects of targeted silencing of heparanase gene by small interfering RNA（siRNA） on invasiveness and metastasis of osteosarcoma cells（MG63 cells） were investigated in the present study.Two complementary oligonucleotide strands were synthesized and inserted into pGenesil-1 vector based on the mRNA sequence of heparanase gene.The expression vector containing short hairpin RNA（pGenesil-shRNA） was constructed successfully.MG63 cells were randomly allocated into 3 groups：blank group,empty vector（pGenesil） transfected group and expression vector（pGenesil-shRNA） transfected group.Under the induction of Lipofectamine 2000,the recombinants were transfected into MG63 cells.Heparanase gene expression level was detected by RT-PCR and Western blotting.Cell prolifera-tion was measured by MTT assay.Cell invasiveness and metastasis were examined by cell adhesion and Transwell-ECM assays.HUVECs migration assay was applied for the detection of angiogenesis.As compared with negative controls,the mRNA and protein expression levels of heparanase were down-regulated by 76.1%（P0.01） and 75.3%（P0.01） respectively in the pGenesil-shRNA transfected group.Meanwhile,the proliferation,adhesiveness,invasiveness and angiogenesis properties of MG63 cells were all significantly inhibited.It was suggested that targeted silencing of heparanase gene by siRNA could dramatically inhibit the invasiveness and metastasis of osteosarcoma cells.

Transfection of Antisense Oligodeoxynucleotide Inhibits Heparanase Gene Expression and Invasive Ability of Human Pancreatic Cancer Cell in vitro

Extracellular matrix （ECM） degradation is an essential step that allows tumor cells to penetrate a tissue barrier and become metastatic. Heparanase （HPSE） is an endoglycosidase that specifically degrades heparin sulfate proteoglycans （HSPG）, a chief component of ECM, HPSE is not expressed in normal epithelial cells but can be detected in a variety of human carcinomas including pancreatic cancer. In the present study, human pancreatic cancer cell line Panc-1 was transfected with HPSE antisense oligodeoxynucleotide （AS-ODN） in vitro, then the inhibitory effect of ASODN on HPSE gene expression and invasive ability of Panc-1 cells in vitro was examined. The HPSE mRNA and protein expression of Panc-1 cells transfected with AS-ODN was significantly inhibited. However, there were no marked inhibitory effects in Panc-1 cells treated with nonsense oligodeoxynucleotide （NS-ODN）. Moreover, a modified Boyden chamber assay demonstrated that transfection with HPSE AS-ODN significantly inhibited invasive potential of Panc-1 cells in vitro after AS-ODN transfection. This suggests that HPSE AS-ODN may contribute to the inhibition of HPSE mRNA and protein expression, and results in a decrease of the invasive ability of Panc-1 in vitro.

heparanase通过调控EMT促进人膀胱移行细胞癌细胞T24迁移及侵袭的作用研究

目的探讨乙酰肝素酶(heparanase)是否通过上皮-间充质转化(EMT)影响膀胱移行细胞癌细胞的侵袭及迁移能力。方法利用荧光定量PCR来检测人膀胱移行细胞癌细胞T24、EJ、MGH-U1以及BIU-87中heparanase的表达水平;设计并合成靶向heparanase的特异性shRNA,通过脂质体转染法转染heparanase表达最高的膀胱移行细胞癌细胞T24以构建稳定低表达heparanase细胞株,通过Western blot法检测和定量PCR来验证shRNA的干扰效率;通过transwell法检测干扰后细胞的迁移及侵袭能力,Western blot法检测EMT相关指标E-cadherin和N-cadherin以及其上游信号分子Snail和WNT-5a的变化。结果 heparanase-shRNA转染后,能够有效抑制T24细胞中heparanase的表达;Transwell法结果显示,heparanase干扰组细胞侵袭及迁移能力显著低于阴性对照组(P<0.001)。Western blot法检测结果发现,heparanase干扰组细胞的E-cadherin表达增加,N-cadherin的表达降低;此外,heparanase干扰组细胞的Snail以及WNT-5a表达较对照组显著下降。结论运用RNA干扰技术能够有效沉默T24细胞的heparanase基因,并诱导其迁移侵袭能力的下降,其可能的机制是通过调节EMT的上游信号分子Snail、WNT-5a的表达来调控EMT,从而影响膀胱移行细胞癌细胞的迁移及侵袭。提示heparanases可能在膀胱移行癌T24细胞的发生发展中起重要作用,抑制heparanase的表达可能成为一种治疗膀胱移行细胞癌的新方法。

GubenyiliuⅡ inhibits breast tumor growth and metastasis associated with decreased heparanase expression and Akt phosphorylation

OBJECTIVE GubenyiliuⅡ(GYⅡ),a traditional Chinese medicine(TCM)formula used in our hospital,has shown beneficial effects in cancer patients.In this study,we investigated the molecular mechanisms underlying the beneficial effects of GYⅡon murine breast cancer models.METHODS Inhibition of tumor growth and metastasis was evaluated by assessment of tumor weight and analysis of bioluminescent signal after a homograft inoculation.Viability of cultured breast cancer cells was determined using MTT assay andreal-time cell analysis(RTCA).Cell migratory ability was evaluated by Transwell?assay and wound healing assay.Subsequently,the potential anti-tumor and anti-metastatic mechanism was investigated by Western blotting and Immunohistochemistry.RESULTS GYⅡshowed significant inhibitory effects on tumor growth and metastasis in the murine breast cancer model.And GYⅡsuppressed theproliferation of 4T1 and MCF-7 cells in a dose-dependent manner.A better inhibitory effect on 4T1 cells proliferation and migration was found in sub-fractions(SF)of GYⅡ.Moreover,heparanase expression and degree of angiogenesis were reduced in tumor tissues.Western blotting analysis showed decreased expression of heparanase and growth factors in the cells treated with GYⅡand its sub-fractions(SF2 and SF3),there by a reduction in phosphorylation of ERK and AKT.CONCLUSION GYⅡexerts anti-tumor growth and anti-metastatic effects on murine breast cancer model.Sub-fractions 2 and 3 exhibits higher potency of the anti-tumor activity that is,at least partly,associated with decreased heparanase and growth factor sexpression,which subsequently sup-pressed activation of ERK and AKT pathways.

EXPRESSION OF HEPARANASE AND ITS CLINICAL SIGNIFICANCE IN HUMAN NON-SMALL CELL LUNG CANCER

Objective： To explore the expression and significance of heparanase in non-small cell lung cancer （NSCLC） regarding prognosis and clinicopathological parameters. Methods： The expression of heparanase was assessed using immunohistochemistry staining and Western blot in 122 paraffin-embedded specimens and 38 freshly taken tissues. The relationship between heparanase expression and the clinicopathological factors was analyzed by Chi-square test, multivariate analysis and Kaplan-Meier method. Results： In the immunoreactive cells, staining was mainly located in cytoplasma and membrane. Human heparanase was highly expressed in lung cancer tissue （78.7%, 96/122） while negative in epithelia of normal lung tissues. The level of heparanase was remarkably higher in NSCLC than that in normal tissue （P=0.043）. Expression of heparanase significantly correlated with TNM stage （P=0.025）, lymphatic metastasis （P=0.002） and vascular invasion （P=0.0003）. The patients with positive heparanase expression had a significantly shorter survival than those with negative heparanase expression （P=0.0006）. In multivariate analysis, only p-TNM stage, lymphatic metastasis and vascular invasion could be considered as prognostic factors. Conclusion： Elevated level of heparanase in human non-small cell lung cancer tissues correlates with the TNM stage, invasion, metastasis and prognosis. However, heparanase expression is not an independent prognostic factor.

正、反义Heparanase基因对肝癌细胞转移潜能的影响

目的 研究正、反义人Heparanase基因对肝癌细胞转移潜能的影响。方法 将正、反义人 Heparanase 基因稳定转染肝癌细胞系HepG2,半定量逆转录-聚合酶链反应(RT-PCR)和免疫组织化学检测转染细胞 Heparanase mRNA及蛋白表达;裸鼠尾静脉注射转染细胞 30 d后,称量肺重、计数肺表面转移结节数;肺脏常规切片、苏木素-伊红(HE)染色。结果 转染正义、反义基因促进或抑制 Heparanase mRNA和蛋白表达;反义组裸鼠肺脏重量、肺表面转移结节数较对照组显著减少(P<0.01),正义组则相反;HE染色表明正义组裸鼠肺脏有大量转移灶,反义组仅见少量小转移灶。结论 Heparanase基因对肝癌细胞转移潜能有明显的促进作用,反义基因则显著抑制肝癌细胞的转移。

heparanase基因及其蛋白表达产物在肿瘤扩散与转移中的作用

阻止肿瘤细胞扩散与转移的主要屏障是细胞外基质(extracellular matrix, ECM)和基底膜(basement menbrane ,BM) ,ECM和BM主要由结构蛋白和糖胺聚糖两种成分构成。糖胺聚糖的主要成分是硫酸乙酰肝素蛋白多糖(heparan sulfate proteoglyean,HSPG) ,heparanase基因在易发生扩散与转移的肿瘤细胞表达上调且表达的产物能降解HSPG,从而促进肿瘤细胞的扩散与转移。文中着重阐述heparanase基因及其蛋白表达产物调节与在肿瘤扩散与转移中的作用现状及相关研究进展。

Changes in Lipoprotein Lipase in the Heart Following Diabetes Onset

Due to its constant pumping and contraction, the heart requires a substantial amount of energy, with fatty acids (FAs) providing a major part of its adenosine triphosphate (ATP). However, the heart is incapable of making this substrate and attains its FAs from multiple sources, including the action of lipoprotein lipase (LPL). LPL is produced in cardiomyocytes and subsequently secreted to its heparan sulfate proteoglycan (HSPG) binding sites on the plasma membrane. To then move LPL to the endothelial cell (EC) lumen, glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) attaches to interstitial LPL and transfers it to the vascular lumen, where the LPL is ready to perform its function of breaking down circulating triglycerides (TG) into FAs. The endo-β-glucuronidase heparanase (Hpa) is unique in that it is the only known mammalian enzyme to cleave heparan sulfate (HS), thereby promoting the abovementioned release of LPL from the cardiomyocyte HSPG. In diabetes, it has been suggested that changes in how the heart generates energy are responsible for the development of diabetic cardiomyopathy (DCM). Following moderate diabetes, with the reduction in glucose utilization, the heart increases its LPL activity at the vascular lumen due to an increase in Hpa action. Although this adaptation might be beneficial to compensate for the underutilization of glucose by the heart, it is toxic over the long term, as harmful lipid metabolite accumulation, along with augmented FA oxidation and thus oxidative stress, leads to cell death. This coincides with the loss of a cardioprotective growth factor—namely, vascular endothelial growth factor B (VEGFB). This review discusses interconnections between Hpa, LPL, and VEGFB and their potential implications in DCM. Given that mechanism-based therapeutic care for DCM is unavailable, understanding the pathology of this cardiomyopathy, along with the contribution of LPL, will help us advance its clinical management.

乙酰肝素酶的mRNA表达与脑胶质瘤分级关系的研究

脑胶质瘤是颅内最常见的恶性肿瘤[1],占颅内肿瘤的35.2%～61.0%。heparanase最早由Parish[2]等发现,是一个关键的胞外基质降解酶,它降解硫酸乙酰肝素和乙酰肝素蛋白聚糖上的聚糖侧链,在肿瘤浸润和转移中起重要作用。

乙酰肝素酶蛋白表达与肝癌侵袭转移关系的研究

乙酰肝素酶（heparanase，HPSE）是一种葡糖苷酸内切酶，能特异性降解硫酸肝素多糖的硫酸肝素侧链，破坏细胞外基质和基底膜，乙酰肝素酶与肿瘤血管形成、侵袭转移密切相关。我们采用免疫组织化学法检测 HPSE 蛋白在肝细胞肝癌、癌旁肝组织及正常肝组织中的表达，探讨 HPSE 蛋白与肝癌临床病理特征的关系。

Protective Effect of Sulodexide on Podocyte Injury in Adriamycin Nephropathy Rats

This study examined the effect of sulodexide on podocyte injury in rats with adriamycin nephropathy （AN）. A total of 36 healthy male SD rats were randomly assigned to three groups： control group, AN group and sulodexide treatment group. Rat models of AN were established by a single tail intravenous injection of adriamycin （6.5 mg/kg） in both AN group and sulodexide treatment group. Sulodexide （10 mg/kg） was administered the rats in the treatment group once daily by garage from the first day of model establishment until the 14th day or the 28th day. Samples of 24-h urine and renal cortex tissues were harvested at day 14, 28 after the model establishment. Excretion of 24-h urinary protein was measured by Coomassie brilliant blue method. The pathological changes in renal tissues were observed by light microscopy and electron microscopy respectively. Heparanase mRNA was detected by RT-PCR. Expressions of desmin, CD2AP and heparanase were determined by immunohistological staining. The results showed that the expressions of heparanase mRNA and protein were increased in the glomeruli of AN rats at day 14 and 28 after the model establishment, which was accompanied by the increased expression of desmin and CD2AP. The mRNA and protein expression of heparanase was decreased in the sulodexide-treated rats as compared with AN rats at day 14 and 28. And, the protein expression of desmin and CD2AP was reduced as with heparanase in the sulodexide-treated rats. Proteinuria and podocyte foot process effacement were alleviated in the AN rats after sulodexide treatment. There was a positive correlation between the expression of heparanase and the expression of desmin and CD2AP （as well as 24-h urinary protein excretion）. It was concluded that increased heparanase is involved in podocyte injury. Sulodexide can maintain and restore podocyte morphology by inhibiting the expression of heparanase in AN.

肝素酶促进肿瘤侵袭及CAR-T细胞抗肿瘤活性

嵌合抗原受体修饰T淋巴细胞（chimeric antigen receptor-redirected T lymphocytes,CAR-T cells）技术是近几年肿瘤免疫治疗突破性方法之一,在一系列临床试验中取得显著疗效,成为新的研究热点。然而目前CAR-T技术主要应用于血液性肿瘤治疗,对于实质性肿瘤则疗效欠佳。美国休斯顿贝勒大学的研究团队发现,肝素酶（heparanase,HPSE）在T淋巴细胞向肿瘤实质的浸润过程中发挥了重要作用,

低氧诱导人视网膜微血管内皮细胞核中乙酰肝素酶对血管内皮生长因子基因转录调控研究

目的通过观察低氧诱导人视网膜血管内皮细胞（HRECs）胞核中乙酰肝素酶（HPA）和RNA聚合酶II（Pol Ⅱ）的表达分布、两者相互结合及其与血管内皮生长因子（VEGF）基因启动子的作用，探讨在低氧诱导视网膜新生血管形成中HPA对VEGF基因转录调控的作用。方法用低氧模型模拟剂Cocl2建立低氧模型（含Cocl2100μmol／L的培养液培养48h）。免疫荧光染色法观察HPA与PolⅡ的表达；免疫沉淀法半定量分析HPA及PolⅡ的相互结合作用；染色质免疫沉淀（ChIP）联合实时定量PCR分析两组细胞中HPA与VEGF基因启动子之间的相互作用。结果（1）免疫荧光染色结果显示低氧诱导组HRECs胞核内HPA荧光和PolII荧光均较正常对照组增强，且低氧诱导组胞核内HPA分布与PolⅡ相吻合。（2）免疫沉淀结果表明在低氧诱导HRECs中HPA及PolⅡ相互结合共同作用，而对照组中HPA及PolⅡ则无结合。（3）ChIP联合实时定量PCR实验结果显示HPA及PolⅡ与VEGF启动子结合的高发生区段主要位于VEGF启动子序列-1165与-984之间，低氧诱导HRECs细胞核内HPA及PolII结合VEGF基因启动子水平均较正常组升高（t=-13．591，P=0．001；t=-3．188，P=0．049）。结论在低氧诱导的HRECs中，核内HPA与VEGF基因启动子直接结合，并参与了VEGF基因转录活性的调控。

Inhibition of Sanggenon G Isolated from Morus alba on the Metastasis of Cancer Cell

Objective An organic layer prepared from the cortex of Morus alba(Moraceae)was studied in order to identify the active compounds for heparinase.Methods Bioassay-guided fractionation resulted in the isolation of sanggenon G.Results The compound showed inhibitory activity with IC50 of 3.7μmol/L on heparinase in vitro as well as 24μmol/L in invasion assay using MDA-MB231 cells.Sanggenon G also had the moderate cytotoxicity at SW 620(colon)and ACHN(kidney)cancer cell lines with IC50 of 10.96 and 13.44μmol/L,respectively.Conclusion This is the first time that prenylated flavonoid sanggenon G is described as heparinase inhibitor.Besides,this flavonoid would be expected to be a metastasis inhibitor of cancer cells and also a valuable reagent to explore the mechanism of heparinase/heparanase-mediated metastasis.