Laminin 5 Regulates Polycystic Kidney Cell Proliferation and Cyst Formation

Abstract

Renal cyst formation is the hallmark of autosomal dominant polycystic kidney disease (ADPKD). ADPKD cyst-lining cells have an increased proliferation rate and are surrounded by an abnormal extracellular matrix (ECM). We have previously shown that Laminin 5 (Ln-5, a α3β3γ2 trimer) is aberrantly expressed in the pericystic ECM of ADPKD kidneys. We report that ADPKD cells in primary cultures produce and secrete Ln-5 that is incorporated to the pericystic ECM in an in vitro model of cystogenesis. In monolayers, purified Ln-5 induces ERK activation and proliferation of ADPKD cells, whereas upon epidermal growth factor stimulation blocking endogenously produced Ln-5 with anti-γ2 chain antibody reduces the sustained ERK activation and inhibits proliferation. In three-dimensional gel culture, addition of purified Ln-5 stimulates cell proliferation and cyst formation, whereas blocking endogenous Ln-5 strongly inhibits cyst formation. Ligation of α6β4 integrin, a major Ln-5 receptor aberrantly expressed by ADPKD cells, induces β4 integrin phosphorylation, ERK activation, cell proliferation, and cyst formation. These findings indicate that Ln-5 is an important regulator of ADPKD cell proliferation and cystogenesis and suggest that Ln-5 γ2 chain and Ln-5-α6β4 integrin interaction both contribute to these phenotypic changes. Renal cyst formation is the hallmark of autosomal dominant polycystic kidney disease (ADPKD). ADPKD cyst-lining cells have an increased proliferation rate and are surrounded by an abnormal extracellular matrix (ECM). We have previously shown that Laminin 5 (Ln-5, a α3β3γ2 trimer) is aberrantly expressed in the pericystic ECM of ADPKD kidneys. We report that ADPKD cells in primary cultures produce and secrete Ln-5 that is incorporated to the pericystic ECM in an in vitro model of cystogenesis. In monolayers, purified Ln-5 induces ERK activation and proliferation of ADPKD cells, whereas upon epidermal growth factor stimulation blocking endogenously produced Ln-5 with anti-γ2 chain antibody reduces the sustained ERK activation and inhibits proliferation. In three-dimensional gel culture, addition of purified Ln-5 stimulates cell proliferation and cyst formation, whereas blocking endogenous Ln-5 strongly inhibits cyst formation. Ligation of α6β4 integrin, a major Ln-5 receptor aberrantly expressed by ADPKD cells, induces β4 integrin phosphorylation, ERK activation, cell proliferation, and cyst formation. These findings indicate that Ln-5 is an important regulator of ADPKD cell proliferation and cystogenesis and suggest that Ln-5 γ2 chain and Ln-5-α6β4 integrin interaction both contribute to these phenotypic changes. Autosomal dominant polycystic kidney disease (ADPKD) 3The abbreviations used are: ADPKD, autosomal dominant polycystic kidney disease; ERK, extracellular signal-regulated kinase; ECM, extracellular matrix; Ln-5, Laminin 5; PBS, phosphate-buffered saline; EGF, epidermal growth factor; Ab, antibody; mAb, monoclonal Ab; pAb, polyclonal Ab; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; DAPI, 4′,6-diamidino-2-phenylindole; PCNA, proliferating cell nuclear antigen. is one of the most common inherited monogenic disorders, occurring in ∼1-1000 live births. ADPKD is a systemic disorder characterized by the development of multiple renal cysts and variably associated with liver, cardiovascular, gastrointestinal, and genital abnormalities. In Western countries, ADPKD accounts for 5-10% of end stage renal disease (1Wilson P.D. N. Engl. J. Med. 2004; 350: 151-164Crossref PubMed Scopus (622) Google Scholar). ∼85% of families with ADPKD are linked to the PKD1 locus on chromosome 16 (2Hughes J. Ward C.J. Peral B. Aspinwall R. Clark K. San Millan J.L. Gamble V. Harris P.C. Nat. Genet. 1995; 10: 151-160Crossref PubMed Scopus (782) Google Scholar). In the remaining families, the genetic defect is linked to the PKD2 locus on chromosome 4 (3Mochizuki T. Wu G. Hayashi T. Xenophontos S.L. Veldhuisen B. Saris J.J. Reynolds D.M. Cai Y. Gabow P.A. Pierides A. Kimberling W.J. Breuning M.H. Deltas C.C. Peters D.J. Somlo S. Science. 1996; 272: 1339-1342Crossref PubMed Scopus (1191) Google Scholar). The proteins encoded by PKD1 and PKD2, polycystins 1 (Pc-1) and 2 (Pc-2), are transmembrane proteins that are able to interact, function together as a non-selective cation channel (4Hanaoka K. Qian F. Boletta A. Bhunia A.K. Piontek K. Tsiokas L. Sukhatme V.P. Guggino W.B. Germino G.G. Nature. 2000; 408: 990-994Crossref PubMed Scopus (671) Google Scholar), and also induce several distinct transduction pathways. The “polycystin complex” may have three different subcellular localizations and associated putative functions (5Boletta A. Germino G.G. Trends Cell Biol. 2003; 13: 484-492Abstract Full Text Full Text PDF PubMed Scopus (88) Google Scholar): at lateral membranes of the cells (with a role in cell-cell interaction) (6Streets A.J. Newby L.J. O'Hare M.J. Bukanov N.O. Ibraghimov-Beskrovnaya O. Ong A.C. J. Am. Soc. Nephrol. 2003; 14: 1804-1815Crossref PubMed Scopus (66) Google Scholar); at the basal pole of the cell (with a role in cell-extracellular matrix interaction) (7Wilson P.D. Geng L. Li X. Burrow C.R. Lab. Investig. 1999; 79: 1311-1323PubMed Google Scholar); and at the apical primary cilia of the cells (with a putative role in the mechanotransduction of the urinary flux) (8Yoder B.K. Hou X. Guay-Woodford L.M. J. Am. Soc. Nephrol. 2002; 13: 2508-2516Crossref PubMed Scopus (737) Google Scholar, 9Nauli S.M. Alenghat F.J. Luo Y. Williams E. Vassilev P. Li X. Elia A.E. Lu W. Brown E.M. Quinn S.J. Ingber D.E. Zhou J. Nat. Genet. 2003; PubMed Google Scholar). In ADPKD renal cysts, somatic mutations of the wild-type allele of PKD1 and PKD2 and subsequent loss of the functional polycystin complex presumably trigger a cascade of signaling and gene expression events, ultimately leading to cyst formation. ADPKD renal cysts originate from the epithelia of the nephrons and collecting ducts. Cyst-lining cells are distinguished by increased proliferation, poor differentiation, and abnormalities in cell polarity, fluid secretion, and extracellular matrix production (1Wilson P.D. N. Engl. J. Med. 2004; 350: 151-164Crossref PubMed Scopus (622) Google Scholar). Expanding cysts must remodel their environment as they enlarge. Morphological anomalies of the cyst-surrounding ECM have been described in human and animal models of polycystic kidney disease. Pericystic ECM appears thickened and multilaminated in the earliest detectable cysts (10Cuppage F.E. Huseman R.A. Chapman A. Grantham J.J. Kidney Int. 1980; 17: 372-381Abstract Full Text PDF PubMed Scopus (97) Google Scholar, 11Cowley Jr., B.D. Gudapaty S. Kraybill A.L. Barash B.D. Harding M.A. Calvet J.P. Gattone II, V.H. Kidney Int. 1993; 43: 522-534Abstract Full Text PDF PubMed Scopus (203) Google Scholar). Cystic epithelial cells produce an abnormal basement membrane and have an abnormal proliferative response to ECM proteins (12Taub M. Laurie G.W. Martin G.R. Kleinman H.K. Kidney Int. 1990; 37: 1090-1097Abstract Full Text PDF PubMed Scopus (38) Google Scholar, 13Beavan L.A. Carone F.A. Nakamura S. Jones J.K. Reindel J.F. Price R.G. Arch. Biochem. Biophys. 1991; 284: 392-399Crossref PubMed Scopus (15) Google Scholar, 14Wilson P.D. Hreniuk D. Gabow P.A. J. Cell. Physiol. 1992; 150: 360-369Crossref PubMed Scopus (83) Google Scholar). Thus, altered extracellular matrix has been postulated to play a role in the pathogenesis of ADPKD. However, the contribution of specific ECM proteins to the development of renal cysts is ill defined. We have previously shown that Laminin 5 is strongly expressed by ADPKD cells and by the pericystic ECM of ADPKD kidneys, whereas no Laminin 5 expression could be detected in adult control kidneys (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar). Laminins are a family of at least 15 multifunctional αβγ heterotrimeric proteins commonly found in basement membranes of epithelia (16Colognato H. Yurchenco P.D. Dev. Dyn. 2000; 218: 213-234Crossref PubMed Scopus (1051) Google Scholar). The various isoforms have a cell- and tissue-specific expression and are differentially recognized by integrins. Laminins undergo a sequential series of extracellular proteolytic cleavages that might successively turn on and off one or several of their biological and mechanical functions through interaction with integrins and other cell surface receptors (17Ghosh S. Stack M.S. Microsc. Res. Tech. 2000; 51: 238-246Crossref PubMed Scopus (38) Google Scholar). Laminin-5 (Ln-5) is a heterotrimer of α3, β3, and γ2 chains. Its cell surface receptors are integrins α6β4, α2β1, α3β1, and α6β1. Mature Ln-5 plays a fundamental role in keratinocyte adherence by promoting through its interaction with α6β4 integrin the assembly of strong and stable adhesion structures called hemidesmosomes (18Nievers M.G. Schaapveld R.Q. Sonnenberg A. Matrix Biol. 1999; 18: 5-17Crossref PubMed Scopus (164) Google Scholar). In peritumoral ECM, Ln-5 is frequently overexpressed, and the proteolytic-driven modulation of its biological activity could trigger tumor progression (19Giannelli G. Falk-Marzillier J. Schiraldi O. Stetler-Stevenson W.G. Quaranta V. Science. 1997; 277: 225-228Crossref PubMed Scopus (1043) Google Scholar) and migration properties with subsequent invasion and metastasis (20Dajee M. Lazarov M. Zhang J.Y. Cai T. Green C.L. Russell A.J. Marinkovich M.P. Tao S. Lin Q. Kubo Y. Khavari P.A. Nature. 2003; 421: 639-643Crossref PubMed Scopus (486) Google Scholar). on of Ln-5 expression in the pericystic ECM in ADPKD, that could cystogenesis. In the the Ln-5 γ2 chain isoforms produced and by ADPKD cyst-lining cells and for a role for Ln-5 in proliferation, and in vitro cystogenesis. Matrix and as β4 and 5 γ2 chain from from from 5 purified Laminin a from Rousselle from from and from and from from human ECM used in Laminin 5 purified from a from Rousselle P. M. J. Cell Biol. PubMed Scopus Google Scholar), and and from for at with Laminin or in with in at for 2 and cell from from other from Cell cell cultures of and as previously described (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar), and used 2 and in 5 5 epidermal growth factor and to as functional proliferation, cells for in to as to with cell and in basal to as and with and various In of a of growth and cells incorporated to of gel and at gel with of at with and a and a at in for functional purified Ln-5 to the gel to the of 5 integrin and integrin 2 to the other Cell culture, ADPKD or control cells the by basal to induce cells with cell and in a at the of in basal to cell the The been previously or with ECM described of the basal by basal the of or The Cell used to of cells and the rate of cell proliferation of the of a an by the of cells, and the at of is to the of cells by a In of proliferation and by of the and by the of cells to addition of In three-dimensional gel culture, at and gel to Cell to the rate of cell proliferation as the gel cells used as for at cells with and in 2 and for at 4 from cells for and membranes from ADPKD In three-dimensional gel the and the gel in to of in the and at on to membranes and detected with the an and in cells and and as β4 of α6β4 in the of cells with cell at and at in with the monoclonal antibody with for the cell at 4 in three with and with 1 at for 5 The proteins to and described with and with polyclonal with in phosphate-buffered for at by at for and for with in PBS, with in with 5 at 4 or 5 at and at or at and a antibody and for at with the to or with Laminin 5 and integrin gel with an and on with and a in at least structures and expressed as a of by and at least three with primary cultures from different ADPKD kidneys. with are as or and by of with the as or Ln-5 and by ADPKD Cystic a that Ln-5 is strongly expressed by the pericystic ECM of ADPKD kidneys, whereas no Ln-5 expression could be detected in adult control kidneys. Ln-5 expression in primary cultures of epithelial cells from ADPKD cysts with control renal epithelial cells (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar). Ln-5 production in vitro cyst formation, ADPKD cells incorporated in three-dimensional and at for structures at and to with and integrin basal cysts, that Ln-5 is incorporated in the ECM a and with the γ2 chain mAb, that Ln-5 are together in the pericystic ECM Ln-5 production by ADPKD cells, with the γ2 chain in various and three-dimensional cell proteolytic of the γ2 chain are in Ln-5 γ2 chain detected in cell of and ADPKD cells 1 and both in its and in its Ln-5 γ2 also found in the of ADPKD cells for a and γ2 and in addition to the a that stimulation These suggest an increased production and of Ln-5 In three-dimensional gel Ln-5 ADPKD cells growth produced of Ln-5 with major at and and a at to γ2 chain the Ln-5 γ2 chain ADPKD cells in and in three-dimensional and the to three-dimensional that a specific proteolytic of the γ2 chain in In cyst fluid from ADPKD and Ln-5 γ2 chain detected that Ln-5 and also in cystogenesis. Ln-5 ADPKD Cell associated with cyst formation in ADPKD is cell proliferation. ADPKD cells a proliferation rate with control cells in or in basal with or in basal ADPKD cells proliferation control cells the of Ln-5 on proliferation in the of cells on or with purified ECM Ln-5, and in basal for Ln-5, or cell proliferation in a with a on ADPKD cells with control cells a with of ADPKD cells both produce Ln-5 and endogenously produced Ln-5 could in ADPKD cell proliferation, ADPKD cells by and with the antibody for shown in cell at a major on cell the of or detected in ADPKD proliferation with a at these suggest that expression of Ln-5 a proliferative to ADPKD cells, with a specific role for the γ2 chain of ERK in ADPKD to their ECM and subsequent activation, integrins induce signaling and and activity Q. M.S. Lin K. J. Biol. Full Text PDF PubMed Google Scholar). of the in turn to control of important for cell proliferation R. Cell. 1995; Full Text PDF PubMed Scopus Google Scholar). We Ln-5 could ERK in ADPKD of detectable on a on and and on In a of ERK activation and that the of ERK activation at of adhesion and We the of the antibody to ERK that ADPKD cells on and by a sustained to 16 with control cells and shown on Ln-5 blocking by antibody ERK activation, whereas no on and these suggest that endogenously produced Ln-5 may contribute to a sustained ERK activation and proliferation of ADPKD cyst-lining Ln-5 in the role of Ln-5 in cyst formation and cyst used the in vitro described in ADPKD cells incorporated in three-dimensional of various of purified Ln-5 to the gel formation, as by the of cysts at Ln-5 to the gel also associated with an increased of cells, as by addition of other to the gel the of cysts at by In three-dimensional gel ADPKD cells with and ultimately structures In the of cells by by with cells with with no of or the role of Ln-5 in proliferation of three-dimensional cells, of in or shown in the of in gel by these suggest that Ln-5 its in three also is a ECM to of ADPKD Ln-5 α6β4 an of ADPKD Cell and have previously shown that integrin α3, and are strongly expressed by both ADPKD and control β4 integrin is detectable in adult epithelial cells, strongly expressed by ADPKD cyst-lining cells with an β4 also that α6β4 integrin expression in vitro in both and primary cultures of ADPKD cells (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar). We to on the role of Ln-5-α6β4 integrin is to be a of ADPKD cyst-lining cells with epithelial Ln-5-α6β4 used the antibody N. N. J. Rousselle P. L. Int. J. 2000; PubMed Scopus Google Scholar). of with ADPKD cells in and β4 at the cell β4 integrin that α6β4 integrin receptor in ERK activation, ADPKD cells on with shown in β4 integrin by strongly these suggest that Ln-5 receptors integrin α6β4 is able to ERK signaling of antibody in basal proliferation of ADPKD cells with a response and 2 We the role of α6β4 integrin and other Ln-5 integrin receptors in cyst formation. In three-dimensional of to the gel increased the of cysts whereas cyst formation by and and by and these indicate that Ln-5 and α6β4 a functional that to proliferation and cystogenesis of ADPKD cells and that other receptors integrin also in cyst formation. that Ln-5 is aberrantly expressed in the pericystic ECM of ADPKD kidneys (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar), the and described in the indicate that ADPKD cyst-lining cells are able to produce and secrete γ2 chains. In in vitro cyst formation ADPKD cells to produce Ln-5 and in the ECM at their basal as by the of integrin with Ln-5 We the proteolytic of the γ2 chain extracellular is to Ln-5 and are to induce γ2 chain M. G. L. Rousselle P. P. J. Cell PubMed Google Scholar, N. T. A. Quaranta V. M. J. Biol. Full Text Full Text PDF PubMed Scopus Google Scholar). of γ2 chain with and 1 and S. E. M. N. R. Quaranta V. J. Cell Biol. 2003; PubMed Scopus Google Scholar). In Ln-5 with mAb, is the of γ2 In the and the of to in are of ADPKD cells in by secrete a of the Ln-5 γ2 chain The described by as an of the γ2 chain of Ln-5 that and has no biological activity S. E. M. N. R. Quaranta V. J. Cell Biol. 2003; PubMed Scopus Google Scholar). ADPKD cells in three-dimensional growth associated with a specific proteolytic of the γ2 and The of the cystogenesis is described by Quaranta S. E. M. N. R. Quaranta V. J. Cell Biol. 2003; PubMed Scopus Google Scholar) as the and found to be of Quaranta have shown that able to with receptor and in vitro phosphorylation, gene and cell in by epithelial cells associated with its In with in vitro also detected the and in the cyst fluid of ADPKD The of in the fluid has been M.J. Jones J.K. Price R.G. Biophys. PubMed Scopus Google Scholar). could that at the apical pole of ADPKD cyst-lining cells could with and cell Ln-5 strong expression at the leading of tumor cell that ECM may on of its on cell migration and a role in cell proliferation. report that ADPKD and control renal epithelial cells on with purified Ln-5 stimulates their with a on ADPKD The promoting role of purified Ln-5 on cell proliferation has been in several epithelial cell and in cells K. J.L. K. M. Biochem. Biophys. Res. 2002; PubMed Scopus Google Scholar, M. K. M. S. Jones Biol. Cell. 1999; 10: PubMed Scopus Google Scholar). stimulation induces the of both ECM proteins and integrin signaling S.J. M.J. J. 2002; Google Scholar). We that in ADPKD cells, stimulation of Ln-5 γ2 chain and stimulates proliferation. that antibody ADPKD cell proliferation that endogenously produced Ln-5 also proliferation in these The γ2 chain of with integrin F. Rousselle P. J. Cell PubMed Google Scholar). The γ2 is the is distinct from the Thus, the blocking of on ADPKD cell proliferation may from integrin from the blocking of the that keratinocyte integrin to Laminin 5 and subsequent adhesion strongly inhibits migration of these cells that the γ2 chain of Ln-5 or of may biological of integrin F. Rousselle P. J. Cell PubMed Google Scholar). the of on ADPKD cell proliferation and cyst formation. Ln-5 may also cell proliferation upon of its chain to its receptor integrins and In response to Ln-5, both integrins shown to epithelial cell proliferation M. K. M. S. Jones Biol. Cell. 1999; 10: PubMed Scopus Google Scholar, F. A. M. J.K. C.J. J. 1997; PubMed Scopus Google Scholar). ADPKD cells and α6β4 whereas control epithelial cells α6β4 integrin (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar). a in integrin receptor could at least ADPKD cells control cells on Ln-5 that β4 integrin to the to induce ADPKD cell proliferation These suggest that Ln-5-α6β4 integrin interaction is to be a of ADPKD cells that is able to proliferation. suggest that is a of the that from Ln-5 in ADPKD adhesion and to purified Ln-5, ADPKD cells β4 integrin by also β4 integrin and ERK activation and the of a functional signaling in ADPKD cells, in with in several epithelial cell M. K. M. S. Jones Biol. Cell. 1999; 10: PubMed Scopus Google Scholar, F. A. M. J.K. C.J. J. 1997; PubMed Scopus Google Scholar). the role of integrin in have found that integrin ERK activation in epithelial cell on Ln-5, the of a signaling M. K. M. S. Jones Biol. Cell. 1999; 10: PubMed Scopus Google Scholar). In ADPKD cells, Ln-5 blocking by antibody the of ERK activation and that the endogenously produced γ2 chain of Ln-5 to the sustained ERK activation of ADPKD The of ERK signaling is for specific biological to ERK activation its sustained nuclear of gene and cell progression C.J. Cell. 1995; Full Text PDF PubMed Scopus Google Scholar, S. J. Nat. Cell Biol. 2002; PubMed Scopus Google Scholar, T. S. M. J. Cell. Physiol. 2002; PubMed Scopus Google Scholar). is that cell interaction with growth and ECM ultimately to activation, and several suggest that both may in a and sequential with growth for ERK activation and subsequent integrin signaling for and sustained ERK activation R. S. J. Cell Biol. PubMed Scopus Google Scholar, R. W.B. M.A. J. Cell Biol. 2003; PubMed Scopus Google Scholar). In the by antibody ERK activity may cell interaction with of the γ2 chain produced and upon that integrin signaling by the functional role of Ln-5 the ECM environment of ADPKD cells in three-dimensional purified Ln-5 to the gel increased the of both cells and cysts and of blocking cystogenesis and able to cell proliferation by and endogenously produced Ln-5 to epithelial tumor cell from in three-dimensional gel N. Russell A. W. Marinkovich M.P. J. Cell Biol. 2003; 163: PubMed Scopus Google Scholar), found that of cyst formation could with no of cell and no major in the of cells These suggest that cell proliferation to cystogenesis. as of cell apical by and assembly of at their basal may also in cyst formation A.L. Zhang Q. Yurchenco P. Nat. Cell Biol. PubMed Scopus Google Scholar, S. M.A. Jones F. M.J. Cell. 2002; Full Text Full Text PDF PubMed Scopus Google Scholar) in several may for the promoting role of Ln-5 γ2 chain on cystogenesis. receptor to be and to the apical pole of the cells in and several animal models of polycystic kidney Jr., Am. J. Physiol. Google Scholar). the W.G. B.K. J. Investig. PubMed Scopus Google Scholar). Thus, Ln-5 γ2 produced and by ADPKD cells, as could receptor and cyst formation. Ln-5 stimulation of integrin receptor signaling may also cystogenesis. has been that loss of integrin, the Ln-5 γ2 in cyst formation by kidney cells in J. Cell 1995; PubMed Google Scholar), blocking integrin cystogenesis in model that the γ2 chain of Ln-5 or its stimulates growth of integrin with and antibody suggest that α6β4, and to a integrin receptors of Ln-5, in ADPKD cell growth We the role of α6β4 signaling in as integrin is in ADPKD (15Joly D. Morel V. Hummel A. Ruello A. Nusbaum P. Patey N. Noel L.H. Rousselle P. Knebelmann B. Am. J. Pathol. 2003; 163: 1791-1800Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar). We that is to the of cysts by ADPKD Ln-5-α6β4 signaling shown to be for epithelial tumor both in three-dimensional gel cultures and in (20Dajee M. Lazarov M. Zhang J.Y. Cai T. Green C.L. Russell A.J. Marinkovich M.P. Tao S. Lin Q. Kubo Y. Khavari P.A. Nature. 2003; 421: 639-643Crossref PubMed Scopus (486) Google Scholar, N. Russell A. W. Marinkovich M.P. J. Cell Biol. 2003; 163: PubMed Scopus Google Scholar, S. M.A. Jones F. M.J. Cell. 2002; Full Text Full Text PDF PubMed Scopus Google Scholar). in primary culture, control renal epithelial cells that α6β4 in three-dimensional and cysts in Thus, Ln-5-α6β4 interaction and subsequent signaling may be one of the in ADPKD cell indicate that Ln-5 is in the pericystic ECM of ADPKD kidneys, and by ADPKD Ln-5 in ADPKD cell ERK activation, and in vitro cystogenesis suggest that ECM may contribute to the development of renal Thus, with cyst-lining interaction may a in ADPKD. We Rousselle for purified Laminin 5 and