Urokinase receptor in human malignant mesothelioma cells: role in tumor cell mitogenesis and proteolysis

1995 ◽  
Vol 268 (6) ◽  
pp. L972-L982 ◽  
Author(s):  
S. Shetty ◽  
A. Kumar ◽  
A. Johnson ◽  
S. Pueblitz ◽  
S. Idell

Urokinase (uPA) interacts with its receptor (uPAR) to promote proteolysis and tumor migration, functions of potential importance in the pathogenesis of malignant mesothelioma. Immunohistochemistry of human malignant mesothelioma tissue and mesothelioma cells (MS-1) showed that mesothelioma cells express uPAR. We isolated uPAR from MS-1 cells by metabolic labeling and showed that it could be induced by phorbol myristate acetate (PMA), lipopolysaccharide (LPS), a transforming growth factor-beta (TGF-beta) or tumor necrosis factor-alpha (TNF-alpha). Experiments with MS-1 cells showed that uPA binding was saturable, specific, and reversible with a mean dissociation constant (Kd) of 5.4 +/- 1.1 nM. Binding was inhibited by a blocking antibody to uPAR and by the uPA amino-terminal fragment (ATF), but not by low molecular weight uPA. uPAR expression was regulated transcriptionally and translationally; antisense oligonucleotides blocked expression of uPAR protein. Plasminogen activator inhibitor-1 (PAI-1) inhibited PA activity of preformed uPA/uPAR complexes and increased cycling of the receptor from the cell surface. Stimulation of subconfluent MS-1 cells by high molecular weight or recombinant uPA, but not ATF or low molecular weight fragment, caused concentration-dependent incorporation of [3H]thymidine. These data indicate a novel mechanism by which malignant mesothelioma cells localize pericellular proteolysis and concurrently regulate tumor cell proliferation.

2008 ◽  
Vol 99 (02) ◽  
pp. 352-356 ◽  
Author(s):  
Muammer Yuce ◽  
Ayse Yazici ◽  
Hasibe Verdi ◽  
F. Belgin Ataç ◽  
Sibel Kinik ◽  
...  

SummaryObesity is associated with the changes of plasminogen activator inhibitor-1 (PAI-1), tumor necrosis factor-alpha (TNFα) and transforming growth factor beta (TGFβ) levels. However, the precise effect of the 4G allele on obesity is still contradictory. Here, we aimed to elucidate the role of the 4G/5G polymorphism of the PAI-1 gene on the PAI-1 level and determine the associations between cytokines, glucose and lipid metabolism parameters in obese children. Thirty-nine obese children (mean age 11.4 ± 3.3 years) and 38 age-matched healthy control group (mean age 10.3 ± 3.5 years) were included in the study. In all cases, serum levels of glucose, lipid and insulin were measured, homeostasis model assessment of insulin resistance (HOMAIR) was calculated, and 4G/5G polymorphism of PAI-1 gene, plasma PAI-1 level and serum TNFα and TGFβ levels were studied. The mean relative body mass index (BMI) and HOMA-IR score, VLDL,TG, insulin, PAI-1,TNFα levels were higher, and HDL and TGFβ levels were lower in the obese group. The frequency of the 4G/4G genotype was considerably higher in obese children than in controls. Also, a positive correlation was found between PAI-1 and TNFα levels, and relative BMI, HOMA-IR score, insulin,TG, HDL levels. TGFβ was inversely correlated only with relative BMI. There was no correlation among three cytokines. In conclusion, childhood obesity contributes to higher PAI-1 andTNFα and lowerTGFβ levels. Especially PAI-1 andTNFα accompany insulin resistance and dyslipidemia.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1658-1658 ◽  
Author(s):  
M. Catherine Driscoll ◽  
Joseph Devaney ◽  
Heather Gordish ◽  
Caterina Minniti ◽  
Eric P. Hoffman

Abstract Cerebrovascular disease is a common complication in sickle cell anemia (SCA) with overt stroke occuring in 10% of patients and silent stroke in 24% of patients by age 20 years. Etiologies of overt stroke in SCA are heterogenous and include stenosis of large arteries, hemorrhage, hypertensive and hypoxic encephalopathy. Candidate genes identified as possible modifiers of overt stroke in SCA include adenylate cyclase 9 (ADCY9, rs731471 intron C/T), endothelin-converting enzyme (ECE-1, rs212527, intron A/G), Klotho (KL, rs480780, intron C/A), plasminogen activator inhibitor-1 (PAI-1, rs1799768, − 675 4/5,), transforming growth factor beta receptor 3 (TGFBR3, rs284157, intron G/A), tumor necrosis factor alpha (TNF, rs1800629,-308 G/A), and interlukin 4 receptor (IL4R, rs1805015, 503S/P). We examined the association of these candidate genes in a cohort of patients with SCA and stenosis of large cerebral vessels who are followed at a single institution. Patients with stenosis (n = 42, male = 22) were identified as having overt stroke (n = 29) or positive transcranial Doppler (TCD) (n = 13). The mean age at time of stroke or (+) TCD was 7.8 years. All had large vessel stenosis on magnetic resonance angiogram imaging (MRA). A control group of patients with SCA and normal TCD were identified (n = 71, males = 46, mean age = 14.8 years).This control group has passed through the peak years of stroke risk, ages 2–10 years. Single nucleotide polymorphisms (SNPs) were genotypic using novel Taqman assays. Genotypic associations were determined using logistic regression analysis with odds ratios (OR), 95% confidence intervals, and p-values reported. Among the candidate genes only ADYC9 (OR = 2.75, CI 1.2–6.3, p = 0.017) and TGFBR3 (OR = 2.33, CI 1.0–5.3, p = 0.043) had significant association with stenosis of large vessels in SCA. ADYC9 is a membrane-associated enzyme that catalyzes cAMP formation, which is critical for neuronal signaling and survival. TGFBR3 has a role in cardiac endothelial cell transformation to mesenchyme. Genotypic studies of a complex trait such as stroke in SCA will eventually lead to early diagnosis and new or early interventions. However, such genetic studies require clear definitions of phenotypic subtypes based on neuroimaging studies, including MRA.


Author(s):  
Jayarami Reddy Medapati ◽  
Deepthi Rapaka ◽  
Veera Raghavulu Bitra ◽  
Santhosh Kumar Ranajit ◽  
Girija Sankar Guntuku ◽  
...  

Abstract Background The endocannabinoid CB1 receptor is known to have protective effects in kidney disease. The aim of the present study is to evaluate the potential agonistic and antagonistic actions and to determine the renoprotective potential of CB1 receptors in diabetic nephropathy. The present work investigates the possible role of CB1 receptors in the pathogenesis of diabetes-induced nephropathy. Streptozotocin (STZ) (55 mg/kg, i.p., once) is administered to uninephrectomised rats for induction of experimental diabetes mellitus. The CB1 agonist (oleamide) and CB1 antagonist (AM6545) treatment were initiated in diabetic rats after 1 week of STZ administration and were given for 24 weeks. Results The progress in diabetic nephropathy is estimated biochemically by measuring serum creatinine (1.28±0.03) (p < 0.005), blood urea nitrogen (67.6± 2.10) (p < 0.001), urinary microprotein (74.62± 3.47) (p < 0.005) and urinary albuminuria (28.31±1.17) (p < 0.0001). Renal inflammation was assessed by estimating serum levels of tumor necrosis factor alpha (75.69±1.51) (p < 0.001) and transforming growth factor beta (8.73±0.31) (p < 0.001). Renal morphological changes were assessed by estimating renal hypertrophy (7.38± 0.26) (p < 0.005) and renal collagen content (10.42± 0.48) (p < 0.001). Conclusions From the above findings, it can be said that diabetes-induced nephropathy may be associated with overexpression of CB1 receptors and blockade of CB1 receptors might be beneficial in ameliorating the diabetes-induced nephropathy. Graphical abstract


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