The extracellular matrix (ECM) plays an important regulatory role in cell shape determination, adhesivity, growth control and differentiation. Excessive ECM accumulation occurs in several clinically important fibroproliferative diseases leading to loss of normal tissue architecture, defects in cellular growth control and impaired organ function. To clarify how these events are related, with reference to the biology of fibrotic disorders, our studies have focused on a specific ECM-associated 32-kDa glycoprotein (p52) the expression of which is greatly elevated in fibroproliferative diseases involving the orbit, lungs, liver, and kidneys. We have recently identified p52 as plasminogen activator inhibitor type-1 (PAI-1), a potential determinant of the pericellular proteolytic environment and of ECM organization/stability. Our long-term goals are to determine the function of p52(PAI-1) in kidney cell growth control, to ascertain its role in the etiology of renal fibrosis and to identify specific molecular mechanisms underlying growth factor/ECM- mediated regulation of p32(PAI-1) gene expression in renal cells. These studies will lead to the development of new clinical strategies focusing on use of the p52(PAI-1) gene and its regulatory network as therapeutic """"""""targets"""""""" in the treatment of fibroproliferative disorders. We hypothesize that (a) structural elements of the ECM, either directly or through changes in cell shape, transduce specific signals which regulate p52(PAI- 1) gene expression, (b)ECM-associated p52(PAI-1) is a key determinant in renal cell substrate adhesion and growth control and (c) modulation of p52(PAI-1) expression results in disease-related changes in renal cell growth traits. To evaluate these hypotheses, the following specific aims will be addressed: 1. We will define specific molecular mechanisms whereby p52(PAI-1) gene expression in renal cells is positively regulated by components of the ECM focusing, in particular, on structural elements of the ECM implicated in renal fibroproliferative disease. 2. We will identify specific genetic elements in renal cells which function to regulate p32(PAI-1) gene expression in the ECM-dependent inductive pathway and determine whether they are the same or different from sequences involved in growth factor- and cell shape-dependent gene control. 3. We will utilize our recently prepared panel of genetically engineered renal cells, designed to over- and under-express p52(PAI-1) specifically, to define the consequences of p32(PAI-1) expression perturbation on renal cell growth traits and their phenotypic response to factors implicated in renal fibroproliferative disorders. 4. We will evaluate the usefulness of directed molecular and chemotherapeutic agents to target the p52(PAI-1) gene and down regulate p52(PAI-1) expression using both in vitro and in vivo models of renal fibrotic disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK046272-04
Application #
2016645
Study Section
Pathology A Study Section (PTHA)
Project Start
1994-01-01
Project End
1999-12-31
Budget Start
1997-01-01
Budget End
1999-12-31
Support Year
4
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Albany Medical College
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
City
Albany
State
NY
Country
United States
Zip Code
12208
Kutz, S M; Providence, K M; Higgins, P J (2001) Antisense targeting of c-fos transcripts inhibits serum- and TGF-beta 1-stimulated PAI-1 gene expression and directed motility in renal epithelial cells. Cell Motil Cytoskeleton 48:163-74
White, L A; Bruzdzinski, C; Kutz, S M et al. (2000) Growth state-dependent binding of USF-1 to a proximal promoter E box element in the rat plasminogen activator inhibitor type 1 gene. Exp Cell Res 260:127-35
Providence, K M; Kutz, S M; Staiano-Coico, L et al. (2000) PAI-1 gene expression is regionally induced in wounded epithelial cell monolayers and required for injury repair. J Cell Physiol 182:269-80
Suzuki, T; Higgins, P J; Crawford, D R (2000) Control selection for RNA quantitation. Biotechniques 29:332-7
Boehm, J R; Kutz, S M; Sage, E H et al. (1999) Growth state-dependent regulation of plasminogen activator inhibitor type-1 gene expression during epithelial cell stimulation by serum and transforming growth factor-beta1. J Cell Physiol 181:96-106
Slack, J K; Higgins, P J (1999) Attenuation of plasminogen activator inhibitor type-1 promoter activity in serum-stimulated renal epithelial cells by a distal 5' flanking region. Cell Motil Cytoskeleton 44:168-76
Higgins, P J; Slack, J K; Diegelmann, R F et al. (1999) Differential regulation of PAI-1 gene expression in human fibroblasts predisposed to a fibrotic phenotype. Exp Cell Res 248:634-42
Providence, K M; Kutz, S M; Higgins, P J (1999) Perturbation of the actin cytoskeleton induces PAI-1 gene expression in cultured epithelial cells independent of substrate anchorage. Cell Motil Cytoskeleton 42:218-29
Mu, X C; Staiano-Coico, L; Higgins, P J (1998) Increased transcription and modified growth state-dependent expression of the plasminogen activator inhibitor type-1 gene characterize the senescent phenotype in human diploid fibroblasts. J Cell Physiol 174:90-8
Hawks, K; Higgins, P J (1998) Cell shape-dependent pathway of plasminogen activator inhibitor type-1 gene expression requires cytoskeletal reorganization. J Cell Physiol 176:293-302

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