Role of Tissue Factor Pathway Inhibitor-2 in Ovarian Tumor Migration and Invasion

Objective: To elucidate the relation between human tissue factor pathwayinhibitor-2 (TFPI-2) expression and ovarian tumor migration and invasion. Methods: Human TFPI-2expression vector pBos-Cite-neo/TFPI-2 was transfected into ovarian tumor cells line A2780- Afterthe transfected cells were selected by G418, transfected and nontransfected cells were screened forTFPI-2 mRNA and protein by reverse transcription-polymerase chain reaction and Western blotanalysis, respectively. The number of transfected or nontransfected cells passing through membraneof Boyden chamber was counted as the basis assessing tumor cells migratory and invasive behaviors.Results: Expression of mRNA and protein of TFPI-2 was detectable in transfected cells. In invasionassay, the number of TFPI-2-expressing cells to traverse a Matrigel-coated membrane was obviouslydecreased compared with that of nonexpressing cells (59.3±6.5 vs 109.7±5.5, P 【 0.01); While inmigration assay, no significant difference through a noncoated membrane was observed amongtransfected and nontransfected cells (114.7±8.6 vs 127.3±7.1, P 】 0.05). Conclusion: Expression ofTFPI-2 may strongly inhibit the invasive ability of ovarian tumor cells in vitro, but has no effecton the migratory ability which provides an experimental basis for genotherapy of human ovariantumor.

Clinical significance of expression of tissue factor and tissue factor pathway inhibitor in ulcerative colitis

AIM: To investigate the clinical significance of expression of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in ulcerative colitis (UC).

Expressions of Tissue Factor and Tissue Factor Pathway Inhibitor in Patients with Acute Graft-versus-host Disease after Allogeneic Hematopoietic Stem Cell Transplantation

This study examined the expressions of human serum tissue factor （TF） and tissue factor pathway inhibitor （TFPI） in patients with acute graft-versus-host disease （aGVHD） after allogeneic hematopoietic stem cell transplantation （allo-HSCT） and their clinical significance. The serum TF and TFPI levels were detected by ELISA in 28 allo-HSCT recipients before and after the transplanta-tion and the changes of TF and TFPI levels were dynamically monitored at different phases of the disease. No significant differences in the serum TF and TFPI levels were found in allo-HSCT recipi-ents in the absence of aGVHD or with gradeⅠaGVHD before and after the transplantation. The lev-els of serum TF and TFPI were substantially increased in the patients with gradeⅡ aGVHD at the peak of aGVHD （P〈0.05） and they were even higher in the patients with grade Ⅲ–Ⅳ aGVHD （P〈0.01）. When the conditions became stable after treatment with immunosuppressive agents, the serum TFPI level was decreased to the baseline level （P〉0.05） and the TF level was lowered but still higher than the baseline level （P〈0.05）. It was concluded that the levels of serum TF and TFPI were increased significantly in the patients with grade Ⅱ–Ⅳ aGVHD after allo-HSCT and decreased markedly after the treatment. Monitoring the levels of serum TF and TFPI in the patients with allo-HSCT is important to predict the occurrence, outcome and prognosis of aGVHD.

Expression of tissue factor in pancreatic adenocarcinoma is associated with activation of coagulation

AIM： To study expression of tissue factor （TF） in pancreatic cancer and its role in the development of thromboembolism.METHODS： TF expression was studied in eight human pancreatic carcinoma cell lines by Northern blot and indirect immunofluorescence. Expression of alternatively spliced TF （asTF） was assessed by RT-PCR. In addition, TF expression was determined by immunofluorescence in pancreatic tissues of 19 patients with pancreatic adenocarcinoma （PCa）, 9 patients with chronic pancreatitis （CP） and 20 normal controls. Plasma samples （30 PCa-patients, 13 CP-patients and 20 controls） were investigated for soluble TF levels and coagulation activation markers [thrombin-antithrombin Ⅲ complex （TAT）, prothrombin fragment 1 ＋ 2 （F1 ＋ 2）]. RESULTS： All pancreatic carcinoma cell lines expressed TF （8/8） and most of them expressed asTF （6/8）. TF expression at the protein level did not correlate with the differentiation of the carcinoma cell line. All but two pancreatic cancer tissue samples stained positive for TF （17/19）. In all samples of CP weak staining was restricted to pancreatic duct cells, whereas only a few subendothelial cells were positive in 9/20 of normal controls. TF and TAT levels in PCa patients were significantly elevated compared to controls whereas elevated F1 ＋ 2 levels did not reach statistical significance compared to controls. In CP patients TAT and F1 ＋ 2 levels proved to be significantly elevated compared to controls, although TAT elevation was less pronounced than in PCa patients. CONCLUSION： We conclude that in addition to the upregulated expression of TF on the cell membrane, soluble TF might contribute to activation of the coagulation system in pancreatic cancer.

A fusion protein containing murine vascular endothelial growth factor and tissue factor induces thrombogenesis and suppression of tumor growth in a colon carcinoma model

Induction of tumor vasculature occlusion by targeting a thrombogen to newly formed blood vessels in tumor tissues represents an intriguing approach to the eradication of primary solid tumors. In the current study, we construct and express a fusion protein containing vascular endothelial growth factor (VEGF) and tissue factor (TF) to explore whether this fusion protein has the capability of inhibiting tumor growth in a colon carcinoma model. The murine cDNA of VEGF A and TF were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), and then cloned into prokaryotic expression plasmid pQE30 with a linker. The expression product recombinant VEGF-TF (rVEGF-TF) was purified and proved to have comparable enzyme activity to a commercial TF and the capability of specific binding to tumor vessels. Significant decrease of tumor growth was found in the mice administered with rVEGF-TF on Day 6 after initiated rVEGF-TF treatment (P<0.05), and the tumor masses in 2 of 10 mice were almost disappeared on Day 14 after the first treatment. In addition, valid thrombogenesis and tumor necrosis were observed in the tumor tissues injected with rVEGF-TF. Our results demonstrate that occlusion of tumor vasculature with rVEGF-TF is potentially an effective approach for cancer therapy.

Homocysteine-induced Enhanced Expression of Tissue Factor in Human Vascular Smooth Muscle Cells

The homocysteine （Hcy）-induced tissue factor （TF） expression in human vascular smooth muscle cells （VSMCs） and the effect of Hcy on the activity of nuclear factor-kappaB （NF-кB） and the expression of inducible nitric oxide synthase （iNOS） were investigated. Human umbilical artery VSMCs were cultured by tissue explanting method, identified by α-actin immunohistochemistry, and incubated with different concentrations of Hcy/PTDC （NF-кB inhibitor）. Semi-quantitative RT-PCR was performed to detect the expression of TF mRNA in VSMCs. Flow cytometry was used to assay the expression of TF protein on the surface of VSMCs and the expression of iNOS in VSMCs. Western blot was carried out to detect the expression of NF-кB protein in nuclei. The results showed that Hcy could induce VSMCs expressing TF mRNA significantly after the VSMCs were incubated with Hcy at concentrations of 10, 100, 500 μmol/L respectively. There was low expression level of TF protein on the surface of the resting VSMCs and Hcy could also induce VSMCs expressing TF pro- tein on the cell surface in different concentrations. Additionally, Hcy could rapidly induce the activation of NF-кB and this effect could be significantly inhibited by PDTC. Hcy alone could not induce the expression of iNOS in VSMCs. It was concluded that Hcy could significantly induce the expression of TF in VSMCs and enhance the activation of NF-ΚB, subsequently mediate TF gene expression and protein synthesis. NF-кB-mediated expression of TF in VSMCs might be the important mechanism of atherosclerosis and thrombosis induced by Hcy.

Positive correlation between plasma PCSK9 and tissue factors levels in patients with angiographically diagnosed coronary artery disease and diabetes mellitus

Background Pro-protein convertase subtilisin/kexin type 9 （PCSK9） is a secreted protein that influences plasma levels of low-density lipoprotein cholesterol （LDL-C）. Both oxidized LDL and tissue factor （TF） contributed to the development of prothrombofic state. The pre- sent study aims to explore the relationship between plasma level of PCSK9 and that of TF in patient with coronary artery disease （CAD）. Methods From July 2013 to March 2014, we enrolled 197 consecutive patients who underwent coronary angiography because of suspected CAD at Beijing Anzhen Hospital in this study. All patients had no history of using lipid-lowering medication. Of these 197 patients （1B 1 male and 66 female, mean age 56.9 ± 11.8 years）, 81 had angiographically diagnosed CAD. Clinical data were collected. Plasma PCSK9 and TF were measured using enzyme-linked immunosorbent assay （ELISA）. Levels of plasma PCSK9 and TF were compared and their correlation analyzed among different patient groups. Results Both plasma levels of PCSK9 （279.8 ± 60.4μg/L vs. 216.5 ± 45.3μg/L, P 〈 0.01） and TF （156.4 ± 26.6 μg/mL vs. 112.1 ± 38.3 μg/L, P 〈 0.01） were significantly higher in patients with CAD, as compared with those with- out CAD. Correlation analysis showed plasma level of PCSK9 was significantly correlated with that of TF in both patients with and without CAD. However, multivariate regression analysis after adjustment for age, gender, smoking, alcohol, hypertension and hyperlipidemia showed that only in CAD patients with type 2 diabetes mellitus, there was significant positive correlation between plasma levels of PCSK9 and TF （β = 0.353, P 〈 0.01）. Coneluslons The plasma level of PCSK9 is independently and positively associated with that of TF in CAD patients with diabetes mellitus, but not in those without diabetes mellitus. Further study is needed to investigate the underlying mechanism.

cytoplasmic domain of tissue factor promotes liver fibrosis in mice

To evaluate the role of tissue factor (TF) and protease activated receptor (PAR)-2 in liver fibrosis. METHODSUsing CCl4 administration for eight weeks, we induced hepatic fibrosis in wild-type C57BL/6 mice and in mice with deletion of the cytoplasmic signalling domain of TF (TF§CT/§CT), deletion of PAR-2 (PAR-2-/-) and combined deletion of TF signalling domain and PAR-2 (TF§CT/§CT/PAR-2-/-). Hepatic fibrosis area was assessed by quantitative imaging of picrosirius red staining. Hepatic collagen content was assessed by hydroxyproline levels. Hepatic stellate cells (αSMA positive) and hepatic macrophages (CD68 positive) were identified by immunohistochemistry. Hepatic gene expression was determined by PCR and liver TGFβ1 content by ELISA. RESULTSCCl4 treated mice with deletion of the PAR-2 gene (PAR-2-/-) and the cytoplasmic domain of TF (TF§CT/§CT) developed significantly less hepatic fibrosis, characterised by reduced liver fibrosis area and hydroxyproline content, compared to control wildtype mice treated with CCl4. The observed reduction in histological fibrosis was accompanied by a significant decrease in the hepatic content of TGFβ, the prototypic fibrogenic cytokine, as well as fewer activated hepatic stellate cells and hepatic macrophages. Deletion of the TF cytoplasmic signalling domain reduced hepatic fibrosis to levels similar to those observed in mice lacking PAR-2 signalling but combined deletion provided no added protection against fibrosis indicating a lack of mutual modulating effects that have been observed in other contexts such as angiogenic responses. CONCLUSIONTissue factor cytoplasmic domain is involved in TF-PAR-2 signalling initiating hepatic fibrosis and is a potential therapeutic target, as its deletion would not impact coagulation.

Binding of EGF1 Domain Peptide in Coagulation Factor Ⅶ with Tissue Factor and Its Implications for the Triggering of Coagulation

The binding function of EGF1 domain peptide with tissue factor(TF)and its ability of triggering coagulation were explored.The TF expression model in vitro was established by lipopolysaccha-ride induction.The affinity of EGFP-EGF1 and TF expressing cells was analyzed by fluorescence microscopy and flow cytometry(FCM).The affinity of EGFP-EGF1 and rat soluble TF was quantitated by surface plasmon resonance(SPR).The ability of EGFP-EGF1 in triggering coagulation was tested by prothrombin time assay.The FCM res...

Down-regulation of Tissue Factor by siRNA Increased Doxorubi-cin-induced Apoptosis in Human Neuroblastoma

The effects of tissue factor （TF） on doxorubicin-induced apoptosis in human neuroblastoma were investigated. The expression of TF was examined by Western blotting. TFsiRNA-pSUPER plasmid was constructed by inserting specific 19-nt silencing sequence targeting TF gene into pSUPER vector. Transfection of TFsiRNA-pSUPER was performed using lipofectamine^2000. The cytotoxicity of doxorubicin was determined by WST assay. The activation of Caspase-3 and PARP induced by doxorubicin was tested by Western blotting. The apoptotic cells were stained by Hochest33342 and counted under fluorescence inverted microscope. It was found that human neuroblastoma cell line SK-N-MC expressed high level of TE Knockdown of the TF expression was achieved by transfection of TFsiRNA-pSUPER on SK-N-MC cells in a dose-dependent manner. Inhibition of TF significantly decreased the viability of transfected SK-N-MC cells treated with different concentrations of doxorubicin. Cleavage of Caspase-3 and PARP was enhanced in transfected SK-N-MC cells with down-regulation of TF. TFsiRNA treatment significantly increased the number of apoptotic cells in transfected SK-N-MC cells as compared with those control cells （P〈0.05） when these cells were exposed to 1 μg/mL doxorubicin for 8 h. These results suggested that knockdown of the TF expression by specific siRNA vector could increase the cytotoxicity of doxorubicin and enhance doxorubicin-induced apoptosis in human neuroblastoma cells. Over-expression of TF might contribute to chemotherapy resistance in human neuroblastoma and its progression, at lest in part, by regulating doxorubicin-induced apoptosis.

Testosterone alleviates tumor necrosis factor-alpha-mediated tissue factor pathway inhibitor downregulation via suppression of nuclear factor-kappa B in endothelial cells

We have observed earlier that testosterone at physiological concentrations can stimulate tissue factor pathway inhibitor(TFPI)gene expression through the androgen receptor in endothelial cells.This study further investigated the impact of testosterone on TFPI levels in response to inflammatory cytokine tumor necrosis factor-alpha(TNF-α).Cultured human umbilical vein endothelial cells were incubated in the presence or absence of testosterone or TNF-α.TFPI protein and mRNA levels were assessed by enzyme-linked immunosorbent assay and quantitative real-time reverse transcription polymerase chain reaction.To study the cellular mechanism of testosterone’s action,nuclear factor-kappa B(NF-κB)translocation was confirmed by electrophoretic mobility shift assays.We found that after NF-κB was activated by TNF-α,TFPI protein levels declined significantly by 37.3%compared with controls(P<0.001),and the mRNA levels of TFPI also decreased greatly(P<0.001).A concentration of 30 nmol L-1 testosterone increased the secretion of TFPI compared with the TNF-α-treated group.NF-κB DNA-binding activity was significantly suppressed by testosterone(P<0.05).This suggests that physiological testosterone concentrations may exert their antithrombotic effects on TFPI expression during inflammation by downregulating NF-κB activity.

Tissue factor with age-related macular degeneration

Wet age-related macular degeneration which incidence increases year by year is a blinding eye disease, but current clinical methods of treatment on this disease are limited and the outcome is not ideal. Recent studies have found abnormally high expression of tissue factors which are targets for the treatment of wet age-related macular degeneration to achieve a certain effect in the choroidal neovascularization. Related literatures are reviewed as following.

Beneficial effect of refined red palm oil on lipid peroxidation and monocyte tissue factor in HCV-related liver disease： a randomized controlled study

BACKGROUND： A large amount of endotoxin can be detected in the peripheral venous blood of patients with liver cirrhosis, contributing to the pathogenesis of hepatotoxicity because of its role in oxidative stress. The present study aimed to test the effect of the supplementation with red palm oil（RPO）, which is a natural oil obtained from oil palm fruit（Elaeis guineensis） rich in natural fat-soluble tocopherols, tocotrienols and carotenoids, on lipid peroxidation and endotoxemia with plasma endotoxin-inactivating capacity, proinflammatory cytokines profile, and monocyte tissue factor in patients with chronic liver disease. METHODS： The study group consisted of sixty patients（34 males and 26 females; mean age 62 years, range 54-75） with Child A/B, genotype 1 HCV-related cirrhosis without a history of ethanol consumption, randomly enrolled into an 8-week oral daily treatment with either vitamin E or RPO. All patients had undergone an upper gastrointestinal endoscopy 8 months before, and 13 out of them showed esophageal varices.RESULTS： Both treatments significantly decreased erythrocyte malondialdehyde and urinary isoprostane output, only RPO significantly affected macrophage-colony stimulating factor and monocyte tissue factor. Liver ultrasound imaging did not show any change. CONCLUSIONS： RPO beneficially modulates oxidative stress and, not least, downregulates macrophage/monocyte inflammatory parameters. RPO can be safely advised as a valuable nutritional implementation tool in the management of chronic liver diseases.

Anisodamine Inhibits Endotoxin-induced Tissue Factor Expression in Human Endothelial Cells

By study on the effect of anisodamine on lipopolysaccharide- induced expression of tissue factor(TF) in vascular endothelial cells(EC) ,the mechanism of anisodam ine antithrom bosis,as well as in the treatm ent of bacteraemic shock was investigated.Human umbilical vein endothelial cells (HUVECs) were cultured by trypsin digestion m ethod.TF activity was measured in the lysates of HUVEC by using a single step clotting assay.Specific m RNA expression was detected by Northern blotting.In order to evaluate a possible contribution of the nuclear factor (NF) -κB pathway on the effects observed,electrophoretic mobility shift assays(EMSA) were performed using nuclear extracts from HU VECs and NF- κB- binding oligonucleotides.The results showed that treatment of HUVEC with L PS resulted in a significant increase in TF activity.Anisodamine dose- dependently inhibited L PS- induced upregulation of TF.These effects was also confirm ed on the level of specific TF m RNA expression by Northern blotting.Furtherm ore,EMSA showed that anisodamine com pletely abolished L PS- induced NF-κB DNA binding activity in nuclear ex- tracts from HUVECs treated with L PS together with anisodamine.The results suggest thataniso- damine counteracts endothelial cell activation by inhibiting L PS- induced TF expression in these cells.Its interference with the NF- κB pathway might- at least in part- contribute to this effect. The ability of anisodamine to counteract L PS effect on endothelial cells m ight be one underlying m echanism explaining its antithrombosis and efficacy in the treatment of bacteraemic shock.

Phosphorothioate oligonucleotide inhibits tissue factor expression in endothelial cells induced by blood flow shear stress in rats

Objective： To determine the effect of antiparallel phosphorothioate triplex-forming oligonucleotide （apsTFO）, which was designed according to shear stress response element （SSRE） in tissue factor （TF） gene promoter region, on the expression of endothelial TF in carotid artery stenosis rats. Methods： Rat model of severe carotid artery stenosis were inflicted by silica gel tube ligation. Half an hour before the model infliction, GT20-apsTFO, GT20-psTFO and GT21-apsTFO labeled with green fluorescence （FITC） were injected into the vena caudalis of rat at a dose of 0.5 mg/kg. Half an hour, 4 or 9 h after the ligation, the distribution of TFO in the common carotid artery, the liver and the kidney was detected with aid of fluorescence microscopy. And the mRNA and protein expressions of TF, Egr-1 and Spl in the above-mentioned organs were determined with in situ hybridization and immunohistochemical assay respectively in 6 h after the model establishment, and the results were analyzed with an image analysis system. Results： Only in 1 h after TFO injection, fluorescent granules appeared in the liver, the kidney and the vascular wall and lumen of carotid artery, and then in 4.5 h, they still deposited in above sites except the vascular lumen. GT20-apsTFO and GT21-apsTFO significant down-regulated the mRNA and protein expressions of TF compared to the rats without treatment （P〈0.05）, and the former apsTFO had a more stronger effect than the later （P〈0.05）. GT20-psTFO had no such effect （P〉0.05）. The 3 TFOs had no inhibition on the mRNA and protein expressions of Egr-1 and Spl. Conclusion： Pretreated apsTFO can partly come into the vascular endothelial cells, and inhibit TF expression induced by shear stress, but had no effect on Egr-1 and Spl gene expressions.

Expression and Location of Intracellular Tissue Factor in Atherosclerosis Stable Plaque of ApoE^(-/-) Mice

In the ApoE^-/- mouse model of atherosclerosis （AS） stable plaque, the expression and location of intracellular tissue factor （TF） in the cellular components of AS stable plaque were investigated in order to explore the cellular mechanism of AS thrombosis. Pathological changes of the stable plaque were observed under a microscope. The expression of TF protein was examined in aortic stable plaque of mice by using immunohistochemistry. Color image planimetric system was used to analyze the histological components of the stable plaque and the TF distribution. Under the confocal microscope, the intracellular TF location in the stable plaque of mice was observed. The results showed the cellular area was the major part of stable plaque （67.36%±6.52%, P〈0.01）. The percentage of total area occupied by cellular area was significantly larger than atheromatous gruel and acellular area （P〈0.01）. Macrophages and smooth muscle cells （SMC） were major cells in the cellular area. The percentage of total area occupied by SMC was significantly larger than by macrophages （P〈0.01）. Multiple linear regression analysis showed there was a positive correlation between TF area and SMC area （r=0.616, P=-0.008）, and no correlation was found between TF area and macrophage area （r=0.437, P=0.08）. Pictures of color image planimetric analysis of TF and SMC were merged to highlight areas with co-localization （yellow）, it was concluded that the process could be a cell-mediated TF expression in the stable plaque. SMC may be the major source of TF in AS without plaque rupture.

Protection of tight junction between RPE cells with tissue factor targeting peptide

AIM：To investigate the effect of tissue factor targeting peptide（TF-TP）on retinal pigment epithelium（RPE）cells tight junctions.METHODS：Cell counting kit-8（CCK-8）was used to measure the proliferation of ARPE-19 cells.Expression of tight junction,ZO-1 in ARPE-19 cells was measured by Western blot and immunofluorescent staining.Western blot was also used to detect the expression of tissue factor（TF）.CEC Transmigration Assay was used to measure the migration of ARPE-19 cells.The transport of fluorescent markers [fluorescein isothiocyanate dextrans of 4,10,20（FD4,FD10,FD20） ]and the transepithelial electrical resistance（TEER）were used to measure in ARPE-19 cell RESULTS：CCK-8 assay showed that 5μmol/L TF-TP can inhibit ARPE-19 cells abnormally proliferation stimulated by lipopolysaccharide（LPS;P〈0.05）.LPS increased the transport of fluorescent markers（FD4,FD10,FD20）and decreased TEER levels in ARPE-19 cells,respectively,which were prevented by 5μmol/L TF-TP pretreatment（P〈0.05）. Furthermore,LPS significantly up-regulated the expression of TF and downregulated the expression of ZO-1（P〈0.05）in ARPE-19 cell which was inhibited by the TF-TP（P〈0.05）.In addition,TF-TP inhibited the abnormal migration induced by LPS in ARPE-19 cell（P〈0.05）.CONCLUSION：Our findings suggest that TF-TP suppressed proliferation and migration of ARPE-19 cells induced by LPS,and maintained the RPE tight junctions through inhibition of TF expression and increased expression of ZO-1.

Ligand Induced Conformational Transitions of Tissue Factor ? Loop

Tissue factor（TF）, the cell surface receptor and requisite cofactor for the inactive serine protease factor VⅡa（VⅡa）, binds VⅡa and its zymogen factor VⅡ with picomolar affinity on the cell surface. The TF：VⅡa complex proteolytically converts downstream zymogen factors X and IX to their active protease states in the cascade responsible for thrombogenesis and hemostasis. The TF pathway also produces cellular signaling through protease activated receptors. Here we present a crystal structure of the completely intact surface domain of TF in complex with VⅡa that reveals a significant conformational difference as compared to free TF. A long loop of residue 78~91 of the tissue factor（named Ω loop here） was found to have well-ordered conformation, whereas this loop in free TF has an expanded conformation and is largely disordered. This loop adopts a tight conformation consisting of five β turns in the TF：VⅡa complex. The Ω loop is located at the interface of the proteins of the complex, has a few interactions with VⅡa, and is possible to accommodate the sequence variations of TF in different mammalian species.

Effect of arsenic sulfide on tissue factor expression in acute promyelocytic leukemia cell lines

Objective: To investigate the effect of arsenic sulfide (tetra-arsenic tetra-sulfide As4S4; diarsenic trisulfide As2S3) on tissue factor (TF) expression and procoagulant activity (PCA) of acute promyelocytic leukemia( APL) cell lines ( NB4 and MR2) and the basic mechanism of their role. Methods: NB4 and MR2 cells were respectively treated with As4S4 , As2S3, As4S4 and Cyclohexamide( CHX). PCA of the cells was detected using one-stage clotting assay. TF antigen was detected by ELISA. TF and PML/RARa fusion gene mRNA by semi-quantitive RT-PCR. The PCA and TF antigen of HL-60 and K562 cells were also examined. Results: The PCA and TF antigen level in NB4 and MR2 cells were significantly higher than that in HL-60 and K562 cells. Both As4S4 and As2S3 can down-regulate the TF antigen , TF mRNA transcription and membrane PCA of NB4 and MR2 cells in vitro in a time-dependent manner. The role of As4S4 was stronger than that of As2S3. Both As4S4 and As2S3 had no effect on PML/RARa fusion gene transcription. CHX treatment completely suppressed the down-regulate effect of As4S4 on the TF mRNA expression. Conclusion: As4S4 and As2S3 may down regulate tissue factor expression and PCA of NB4 and MR2 cells. By down-regulating TF expression, As4S4 and As2S3 might be used to improve the DIC-related hemorrhage in APL patients. Elevated TF antigen level of NB4 and MR2 cells may be related to the fusion gene PML/RARa. The modulation of the TF mRNA expression in NB4 and MR2 cells by As4S4 and As2S3 might be indirect and might not involve PML/RARa fusion gene.

Role of tissue factor in hepatocellular carcinoma genesis, invasion and metastasis

Background Numerous studies indicate that tissue factor （TF）, namely tissue thromboplastin, has a close relationship with malignant tumor genesis and progress. It contributes to blood coagulation as well as the regulation of cellular differentiation, the formation of blood vessels, and also tumor recurrence and metastasis. The present study aimed to detect TF expression in hepatocellular carcinoma （HCC） patients and to elucidate its association with prognosis and clinical features of the disease. Methods The plasma TF levels of 50 HCC patients and 30 controls were assayed by ELISA. The expressions of TF mRNA and protein in HCC tissues, adjacent tissues and normal tissues were detected by reverse transcription- polymerase chain reaction （RT-PCR） and Western blotting. The acquired data were analyzed with related clinic-pathological documents. The patients were followed up for five years, and the relationship between TF and prognosis was analyzed. Results The plasma TF levels were significantly increased in HCC compared to the controls （P 〈0.05）, presenting a close relationship with differentiation level, tumor size and hepatocirrhosis occurrence （P 〈0.05）. There were remarkably higher values in cases of lymphatic metastasis, extrahepatic metastasis and portal tumor thrombus （PTT） （P 〈0.05） compared to non-metastasis or non-tumor thrombus, but no significant difference with different focus number or envelope （P 〉0.05）. The positive rates and the relative expression of TF mRNA in HCC tissue were 63.0% （17/27） and 0.567±0.268, respectively, significantly higher than that in adjacent tissues or normal tissues （P 〈0.05）. In the patients with positive results, the relative expression intensity varied significantly with different tumor size and index of local invasion and metastasis （P 〈0.05）. The positive rates and the relative expression intensities of TF protein in HCC tissue were 74.1% （20/27） and 4.093±1.256, respectively, significantly higher than those in adjacent tissue or normal tissue （P 〈0.05）. In the patients with positive results, the relative expression intensity showed significant difference in different tumor size, differentiation level, and index of local invasion and metastasis （P 〈0.05）. Conclusions The TF levels were significantly higher in plasma and tissues of HCC patients, presenting a close relationship with the index of invasion and metastasis. It indicated that TF might be related to differentiation and metastasis of HCC.