2,3,7,8-Tetrachlorodibenzo- p -dioxin (TCDD) induces plasminogen activator inhibitor-1 through an aryl hydrocarbon receptor-mediated pathway in mouse hepatoma cell lines

Abstract Pancreatic cancer patients have a high risk of venous thromboembolism (VTE). Plasminogen activator inhibitor 1 (PAI-1) inhibits plasminogen activators and increases the risk of thrombosis. PAI-1 is expressed by pancreatic tumors and human pancreatic cell lines. However, to date, there are no studies analyzing the association of active PAI-1 and VTE in pancreatic cancer patients. We investigated the association of active PAI-1 in plasma and VTE in pancreatic cancer patients. In addition, we determined if the presence of human pancreatic tumors expressing PAI-1 impairs venous thrombus resolution in mice. Plasma levels of active PAI-1 in patients with pancreatic cancer and mice bearing human tumors were determined by enzyme-linked immunosorbent assay. We measured PAI-1 expression in 5 different human pancreatic cancer cell lines and found that PANC-1 cells expressed the highest level. PANC-1 tumors were grown in nude mice. Venous thrombosis was induced by complete ligation of the inferior vena cava (IVC). Levels of active PAI-1 were independently associated with increased risk of VTE in patients with pancreatic cancer (subdistribution hazard ratio per doubling of levels: 1.39 [95% confidence interval, 1.09-1.78], P = .007). Mice bearing PANC-1 tumors had increased levels of both active human and active mouse PAI-1 and decreased levels of plasmin activity. Importantly, mice bearing PANC-1 tumors exhibited impaired venous thrombus resolution 8 days after IVC stasis compared with nontumor controls. Our results suggest that PAI-1 contributes to VTE in pancreatic cancer.

Download Full-text

Immunoaffinity Purification of HTC Rat Hepatoma Cell Plasminogen Activator-Inhibitor-1

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646047 ◽

1987 ◽

Vol 58 (04) ◽

pp. 1017-1023 ◽

Cited By ~ 23

Author(s):

Ron Zeheb ◽

Usha M Rafferty ◽

Miguel A Rodriguez ◽

Peter Andreasen ◽

Thomas D Gelehrter

Keyword(s):

Plasminogen Activator ◽

Hepatoma Cell ◽

Plasminogen Activator Inhibitor ◽

Hepatoma Cells ◽

Tissue Type ◽

Plasminogen Activator Inhibitor 1 ◽

Major Band ◽

Activator Inhibitor ◽

Pai 1 ◽

Rat Hepatoma

SummaryIncubation of HTC rat hepatoma cells with the synthetic glucocorticoid dexamethasone rapidly inhibits tissue-type plasminogen activator activity by inducing a specific plasminogen activator-inhibitor (PAI-1). Using immobilized polyclonal antibodies raised against HT-1080 human fibrosarcoma PAI-1, we have purified HTC PAI-1 from serum-free medium conditioned by dexamethasone-treated HTC hepatoma cells and shown it to be antigenically related to human PAI-1. Greater than 100-fold purification with greater than 75% yield was achieved in a single step. The purified PAI-1 migrates on SDS-polyacrylamide gels as a single major band of 49 kDa with a minor band of 46 kDa. Digestion of PAI-1 with endoglycosidase F causes a shift toward faster migrating species which retain inhibitory activity. The purified PAI-1 was stable at pH 2.5, lost 50% of its activity after 15 min at 45° C, and showed marked activation after treatment with SDS or guanidine-HCl. Purified PAI-1 rapidly inhibited and formed complexes with both tissue-type and urokinase-type plasminogen activators. Polyclonal rabbit antirat PAI-1 antibodies were raised which immunoprecipitate both free and complexed PAI-1.

Download Full-text

Plasminogen Activator Inhibitor 1 Promotes Immunosuppression in Human Non-Small Cell Lung Cancers by Enhancing TGF-Β1 Expression in Macrophage

Cellular Physiology and Biochemistry ◽

10.1159/000486025 ◽

2017 ◽

Vol 44 (6) ◽

pp. 2201-2211 ◽

Cited By ~ 10

Author(s):

Chengjun Zhu ◽

Hua Shen ◽

Lingjun Zhu ◽

Feng Zhao ◽

Yongqian Shu

Keyword(s):

Plasminogen Activator ◽

Cell Lines ◽

Cell Cultures ◽

Plasminogen Activator Inhibitor ◽

Small Cell ◽

Small Cell Lung ◽

Plasminogen Activator Inhibitor 1 ◽

Macrophage Cell ◽

Activator Inhibitor ◽

Pai 1

Background: Plasminogen activator inhibitor-1 (PAI-1) has been regarded as a risk factor for thrombosis and atherosclerosis. Since it has been shown that PAI-1 can activate macrophages through Toll-like receptor-4, we sought to investigate the role of PAI-1 in the tumor microenvironment. Methods: The expression and distribution patterns of PAI-1 and transforming growth factor beta (TGF-β) were measured in 60 non-small cell lung cancer (NSCLC) tumors. A statistical correlation analysis was performed between PAI-1 and TGF-β expression and distribution in each tumor. The distribution of tumor-associated macrophages (TAMs) was also measured and its correlation to PAI-1 levels was analyzed. Levels of secreted CCL-17, CCL-22, IL-6 and TGF-β were measured in cell cultures of human macrophage cell lines THP-1 and U937 treated with PAI-1. Levels of secreted PAI-1 were monitored in cell cultures of human NSCLCs cell lines 95D and A549 treated with TGF-β. Secreted proteins were measured in cell culture supernatants using ELISA. Changes in downstream signaling pathways were investigated using western blot. Results: PAI-1 and TGF-β were found to be overexpressed in human NSCLCs. PAI-1 expression was tightly correlated to TGF-β expression as well as the percentage of TAMs. PAI-1 treatment increased the expression of TAM-associated cytokines and chemokines, including CCL-17, CCL-22, and IL-6. PAI-1 treatment was also observed to enhance TGF-β expression in macrophage cell lines through an IL-6 autocrine/paracrine manner. The effects on TGF-β expression were blocked by NF-κB and STAT3 inhibition. Interestingly, TGF-β also increased levels of secreted PAI-1 in NSCLC cells through SMAD3-dependent signaling, therefore resulting in a feed-forward loop. However, this loop could be blocked by NF-κB, STAT3 and SMAD3 signaling inhibition, as well as treatment with a high concentration of TGF-β. Conclusion: PAI-1 and TGF-β promote NSCLC tumor cells and TAMs and might be valuable targets for cancer immunosuppression.

Download Full-text

Synthesis of plasminogen activator inhibitor 1 by bovine mammary epithelial and myoepithelial cell lines

Journal of Dairy Research ◽

10.1017/s0022029900031952 ◽

1996 ◽

Vol 63 (3) ◽

pp. 451-458 ◽

Cited By ~ 10

Author(s):

Boris Zavizion ◽

Christian W. Heegard ◽

Jeffrey White ◽

Federica Cheli ◽

Ioannis Politis

Keyword(s):

Plasminogen Activator ◽

Cell Lines ◽

Myoepithelial Cell ◽

Plasminogen Activator Inhibitor ◽

Myoepithelial Cells ◽

Mammary Epithelial ◽

Model Systems ◽

Plasminogen Activator Inhibitor 1 ◽

Activator Inhibitor ◽

Pai 1

SummaryConversion of plasminogen to plasmin provides an important source of proteolytic activity in the bovine mammary gland. Plasminogen activator inhibitor 1 (PAI-1) plays a key role in limiting plasminogen activation. The PAI-1 biosynthetic capabilities of various bovine mammary cells were determined. The immortalized epithelial cell lines MAC-T and BME-UV and the myoepithelial cell line BMM-UV were used as model systems. Northern blot analysis indicated that both epithelial and myoepithelial cells contained PAI-1 mRNA. Bovine PAI-1 was encoded by a single mRNA species ∼ 3·0 kb long. BME-UV cells contained 2·0-fold (P< 0·01) the PAI-1 mRNA of MAC-T or BMM-UV cells. Reverse zymography indicated that both epithelial and myoepithelial cells synthesized PAI-1 protein with a molecular mass of ∼ 50 kDa.

Download Full-text

Plasminogen activator inhibitor-1 synthesis in the human hepatoma cell line Hep G2. Metformin inhibits the stimulating effect of insulin.

Journal of Clinical Investigation ◽

10.1172/jci116445 ◽

1993 ◽

Vol 91 (5) ◽

pp. 2185-2193 ◽

Cited By ~ 57

Author(s):

F Anfosso ◽

N Chomiki ◽

M C Alessi ◽

P Vague ◽

I Juhan-Vague

Keyword(s):

Cell Line ◽

Plasminogen Activator ◽

Hepatoma Cell ◽

Plasminogen Activator Inhibitor ◽

Hepatoma Cell Line ◽

Human Hepatoma ◽

Hep G2 ◽

Plasminogen Activator Inhibitor 1 ◽

Human Hepatoma Cell ◽

Activator Inhibitor

Download Full-text

Identification of a tightly regulated hypoxia-response element in the promoter of human plasminogen activator inhibitor–1

Blood ◽

10.1182/blood.v99.6.2077 ◽

2002 ◽

Vol 99 (6) ◽

pp. 2077-2083 ◽

Cited By ~ 88

Author(s):

Trine Fink ◽

Arunas Kazlauskas ◽

Lorenz Poellinger ◽

Peter Ebbesen ◽

Vladimir Zachar

Keyword(s):

Plasminogen Activator ◽

Messenger Rna ◽

Hepatoma Cell ◽

Plasminogen Activator Inhibitor ◽

Hepatoma Cell Line ◽

Plasminogen Activator Inhibitor 1 ◽

Human Hepatoma Cell ◽

Hypoxia Response ◽

Activator Inhibitor ◽

Pai 1

Abstract Plasminogen activator inhibitor–1 (PAI-1) plays a key role in control of coagulation and tissue remodeling and has been shown to be regulated by a number of cell stimuli, among those hypoxia. In this study we characterize the hypoxia-mediated induction of PAI-1 in human hepatoma cell line HepG2. We found that PAI-1 is tightly regulated in a narrow oxygen gradient. After incubation at oxygen concentrations of 1% to 2%, a 60-fold increase in PAI-1 messenger RNA levels was observed, whereas mild hypoxic conditions of more than 3.5% did not appear to induce transcription. Moreover, increased levels of PAI-1 protein were observed after incubation at low oxygen tensions. Through sequence analysis, several putative hypoxia-response elements (HREs 1-5) were identified in the human PAI-I promoter. Reporter gene assays showed that the HRE-2 (−194 to −187) was necessary and sufficient for the hypoxia-mediated response. By electrophoretic mobility assay we observed hypoxia-dependent binding of a protein complex to the HRE-2 motif. Further analysis demonstrated that HRE-2 was specifically recognized by the hypoxia-inducible transcription factor 1α–arylhydrocarbon nuclear translocator complex. Taken together, our data demonstrate that hypoxia-induced transcription is mediated through HIF-1 interaction with the HRE-2 site of the human PAI-1 promoter.

Download Full-text