Overexpression of E-cadherin on Melanoma Cells Inhibits Chemokine-promoted Invasion Involving p190RhoGAP/p120ctn-dependent Inactivation of RhoA

Melanoma cells express the chemokine receptor CXCR4 that confers high invasiveness upon binding to its ligand CXCL12. Melanoma cells at initial stages of the disease show reduction or loss of E-cadherin expression, but recovery of its expression is frequently found at advanced phases. We overexpressed E-cadherin in the highly invasive BRO lung metastatic cell melanoma cell line to investigate whether it could influence CXCL12-promoted cell invasion. Overexpression of E-cadherin led to defective invasion of melanoma cells across Matrigel and type I collagen in response to CXCL12. A decrease in individual cell migration directionality toward the chemokine and reduced adhesion accounted for the impaired invasion. A p190RhoGAP-dependent inhibition of RhoA activation was responsible for the impairment in chemokine-stimulated E-cadherin melanoma transfectant invasion. Furthermore, we show that p190RhoGAP and p120ctn associated predominantly on the plasma membrane of cells overexpressing E-cadherin, and that E-cadherin-bound p120ctn contributed to RhoA inactivation by favoring p190RhoGAP-RhoA association. These results suggest that melanoma cells at advanced stages of the disease could have reduced metastatic potency in response to chemotactic stimuli compared with cells lacking E-cadherin, and the results indicate that p190RhoGAP is a central molecule controlling melanoma cell invasion. Melanoma cells express the chemokine receptor CXCR4 that confers high invasiveness upon binding to its ligand CXCL12. Melanoma cells at initial stages of the disease show reduction or loss of E-cadherin expression, but recovery of its expression is frequently found at advanced phases. We overexpressed E-cadherin in the highly invasive BRO lung metastatic cell melanoma cell line to investigate whether it could influence CXCL12-promoted cell invasion. Overexpression of E-cadherin led to defective invasion of melanoma cells across Matrigel and type I collagen in response to CXCL12. A decrease in individual cell migration directionality toward the chemokine and reduced adhesion accounted for the impaired invasion. A p190RhoGAP-dependent inhibition of RhoA activation was responsible for the impairment in chemokine-stimulated E-cadherin melanoma transfectant invasion. Furthermore, we show that p190RhoGAP and p120ctn associated predominantly on the plasma membrane of cells overexpressing E-cadherin, and that E-cadherin-bound p120ctn contributed to RhoA inactivation by favoring p190RhoGAP-RhoA association. These results suggest that melanoma cells at advanced stages of the disease could have reduced metastatic potency in response to chemotactic stimuli compared with cells lacking E-cadherin, and the results indicate that p190RhoGAP is a central molecule controlling melanoma cell invasion. Cadherins are a family of Ca2+-dependent adhesion molecules that mediate cell-cell contacts and are expressed in most solid tissues providing a tight control of morphogenesis (1Yagi T. Takeichi M. Genes Dev. 2000; 14: 1169-1180PubMed Google Scholar, 2Gumbiner B.M. Nat. Rev. Mol. Cell Biol. 2005; 6: 622-634Crossref PubMed Scopus (1245) Google Scholar). Classical cadherins, such as epithelial (E) cadherin, are found in adherens junctions, forming core protein complexes with β-catenin, α-catenin, and p120 catenin (p120ctn). Both β-catenin and p120ctn directly interact with E-cadherin, whereas α-catenin associates with the complex through its binding to β-catenin, providing a link with the actin cytoskeleton (1Yagi T. Takeichi M. Genes Dev. 2000; 14: 1169-1180PubMed Google Scholar, 2Gumbiner B.M. Nat. Rev. Mol. Cell Biol. 2005; 6: 622-634Crossref PubMed Scopus (1245) Google Scholar). E-cadherin is frequently lost or down-regulated in many human tumors, coincident with morphological epithelial to mesenchymal transition and acquisition of invasiveness (3Vleminckx K. Vakaet Jr., L. Mareel M. Fiers W. van Roy F. Cell. 1991; 66: 107-119Abstract Full Text PDF PubMed Scopus (1528) Google Scholar, 4Frixen U.H. Behrens J. Sachs M. Eberle G. Voss B. Warda A. Lochner D. Birchmeier W. J. Cell Biol. 1991; 113: 173-185Crossref PubMed Scopus (1408) Google Scholar, 5Navarro P. Gomez M. Pizarro A. Gamallo C. Quintanilla M. Cano A. J. Cell Biol. 1991; 115: 517-533Crossref PubMed Scopus (237) Google Scholar, 6Thiery J.P. Nat. Rev. Cancer. 2002; 2: 442-454Crossref PubMed Scopus (5604) Google Scholar). Although melanoma only accounts for 5% of skin cancers, when metastasis starts, it is responsible for 80% of deaths from skin cancers (7Miller A.J. Mihm Jr., M.C. N. Engl. J. Med. 2006; 355: 51-65Crossref PubMed Scopus (1219) Google Scholar). Melanocytes express E-cadherin (8Tang A. Eller M.S. Hara M. Yaar M. Hirohashi S. Gilchrest B.A. J. Cell Sci. 1994; 107: 983-992PubMed Google Scholar, 9Cowley G.P. Smith M.E. J. Pathol. 1996; 179: 183-187Crossref PubMed Scopus (42) Google Scholar, 10Hsu M. Andl T. Li G. Meinkoth J.L. Herlyn M. J. Cell Sci. 2000; 113: 1535-1542PubMed Google Scholar), but melanoma cells at early radial growth phase show a large reduction in the expression of this cadherin, and surprisingly, expression has been reported to be partially recovered by vertical growth phase and metastatic melanoma cells (9Cowley G.P. Smith M.E. J. Pathol. 1996; 179: 183-187Crossref PubMed Scopus (42) Google Scholar, 11Danen E.H. de Vries T.J. Morandini R. Ghanem G.G. Ruiter D.J. van Muijen G.N. Melanoma Res. 1996; 6: 127-131Crossref PubMed Scopus (94) Google Scholar, 12Silye R. Karayiannakis A.J. Syrigos K.N. Poole S. van Noorden S. Batchelor W. Regele H. Sega W. Boesmueller H. Krausz T. Pignatelli M. J. Pathol. 1998; 186: 350-355Crossref PubMed Scopus (105) Google Scholar). Trafficking of cancer cells from primary tumor sites to intravasation into blood circulation and later to extravasation to colonize distant organs requires tightly regulated directional cues and cell migration and invasion that are mediated by chemokines, growth factors, and adhesion molecules (13Chambers A.F. Groom A.C. MacDonald I.C. Nat. Rev. Cancer. 2002; 2: 563-572Crossref PubMed Scopus (3169) Google Scholar). Solid tumor cells express chemokine receptors that provide guidance of these cells to organs where their chemokine ligands are expressed, constituting a homing model resembling the one used by immune cells to exert their immune surveillance functions (14Balkwill F. Nat. Rev. Cancer. 2004; 4: 540-550Crossref PubMed Scopus (1968) Google Scholar). Most solid cancer cells express CXCR4, a receptor for the chemokine CXCL12 (also called SDF-1), which is expressed in lungs, bone marrow, and liver (15Muller A. Homey B. Soto H. Ge N. Catron D. Buchanan M.E. McClanahan T. Murphy E. Yuan W. Wagner S.N. Barrera J.L. Mohar A. Verastegui E. Zlotnik A. Nature. 2001; 410: 50-56Crossref PubMed Scopus (4566) Google Scholar). Expression of CXCR4 in human melanoma has been detected in the vertical growth phase and on regional lymph nodes, which correlated with poor prognosis and increased mortality (16Longo-Imedio M.I. Longo N. Trevino I. Lazaro P. Sanchez-Mateos P. Int. J. Cancer. 2005; 117: 861-865Crossref PubMed Scopus (63) Google Scholar, 17Scala S. Ottaiano A. Ascierto P.A. Cavalli M. Simeone E. Giuliano P. Napolitano M. Franco R. Botti G. Castello G. Clin. Cancer Res. 2005; 11: 1835-1841Crossref PubMed Scopus (267) Google Scholar). Previous in vivo experiments have provided evidence supporting a crucial role for CXCR4 in the metastasis of melanoma cells (18Murakami T. Maki W. Cardones A.R. Fang H. Tun Kyi A. Nestle F.O. Hwang S.T. Cancer Res. 2002; 62: 7328-7334PubMed Google Scholar). Rho GTPases control the dynamics of the actin cytoskeleton during cell migration (19Ridley A.J. Schwartz M.A. Burridge K. Firtel R.A. Ginsberg M.H. Borisy G. Parsons J.T. Horwitz A.R. Science. 2003; 302: 1704-1709Crossref PubMed Scopus (3928) Google Scholar, 20Jaffe A.B. Hall A. Annu. Rev. Cell Dev. Biol. 2005; 21: 247-269Crossref PubMed Scopus (2415) Google Scholar). The activity of Rho GTPases is tightly regulated by guanine-nucleotide exchange factors (GEFs), 4The abbreviations used are: GEF, guanine-nucleotide exchange factor; siRNA, short interfering RNA; CA, constitutively active; GFP, green fluorescent protein; GAP, GTPase-activating protein; GDI, guanine nucleotide dissociation inhibitor; EMD, Euclidean mean distance; AMD, accumulated mean distance; PBS, phosphate-buffered saline; mAb, monoclonal antibody; BLM, BRO lung metastatic cell. which stimulate exchange of bound GDP by GTP, and inhibited by GTPase-activating proteins (GAPs), which promote GTP hydrolysis (21Schmidt A. Hall A. Genes Dev. 2002; 16: 1587-1609Crossref PubMed Scopus (996) Google Scholar, 22Bos J.L. Rehmann H. Wittinghofer A. Cell. 2007; 129: 865-877Abstract Full Text Full Text PDF PubMed Scopus (1377) Google Scholar), whereas guanine nucleotide dissociation inhibitors (GDIs) appear to mediate blocking of spontaneous activation (23Olofsson B. Cell. Signal. 1999; 11: 545-554Crossref PubMed Scopus (413) Google Scholar). Therefore, cell migration is finely regulated by the balance between GEF, GAP, and GDI activities on Rho GTPases. Involvement of Rho GTPases in cancer is well documented (reviewed in Ref. 24Sahai E. Marshall C.J. Nat. Rev. Cancer. 2002; 2: 133-142Crossref PubMed Scopus (1241) Google Scholar), providing control of both cell migration and growth. RhoA and RhoC are highly expressed in colon, breast, and lung carcinoma (25Fritz G. Just I. Kaina B. Int. J. Cancer. 1999; 81: 682-687Crossref PubMed Scopus (589) Google Scholar, 26van Golen K.L. Wu Z.F. Qiao X.T. Bao L.W. Merajver S.D. Cancer Res. 2000; 60: 5832-5838PubMed Google Scholar), whereas overexpression of RhoC in melanoma leads to enhancement of cell metastasis (27Clark Nature. 2000; PubMed Scopus Google Scholar). CXCL12 both RhoA and in melanoma and both GTPases during invasion toward this chemokine R.A. Longo N. M. Longo I. van Muijen G.N. Sanchez-Mateos P. J. J. Biol. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar, R.A. Longo N. F. Muijen G.N. Sanchez-Mateos P. J. Cancer Res. 2004; PubMed Scopus Google Scholar). the of the in melanoma cell invasion and in this we have the of whether in E-cadherin expression on melanoma cells cell We show that overexpression of E-cadherin leads to impaired melanoma cell invasion to and we provide for the decrease in invasion. and human melanoma cells as R.A. Longo N. M. Longo I. van Muijen G.N. Sanchez-Mateos P. J. J. Biol. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar). provided by Cano de and from from Cell and from and from and from was from was from and was We from B. whereas control and provided by de was from was from and inhibitors and from siRNA, and E-cadherin expression and the from for of type RhoA and and and from and and from Burridge of A of for E-cadherin and and and from whereas for p120ctn was from We used a control as R.A. I. R. Sanchez-Mateos P. J. Cancer Res. 2006; 66: PubMed Scopus Google Scholar). cells with expression or or as reported R.A. I. R. Sanchez-Mateos P. J. Cancer Res. 2006; 66: PubMed Scopus Google Scholar). in the cells by to which was The E-cadherin upon or into cells by and with type E-cadherin and the E-cadherin in of B. These with and in cells as reported R.A. N. I. J. Cancer Res. PubMed Scopus Google Scholar). used to cells that with Expression of E-cadherin was by and as R.A. Longo N. F. Muijen G.N. Sanchez-Mateos P. J. Cancer Res. 2004; PubMed Scopus Google Scholar). cells on the of to for to the with invasion with or CXCL12. cells and a adhesion cells with and in on with Matrigel collagen or to for at by with to was a with Matrigel in of cell into the and for in a cell with and CXCL12 was in the to the the on the of Cell type and cell was a of for in and from cells with of and the of CXCL12 to cell directionality was with and Cell directionality was as the of Euclidean mean accumulated mean Cell with in PBS, cells in and Cell and whereas with and in and membrane proteins for and melanoma cells as R.A. I. R. Sanchez-Mateos P. J. Cancer Res. 2006; 66: PubMed Scopus Google Scholar), and with by to protein in by and to with primary by with and with activity as reported R.A. Longo N. F. Muijen G.N. Sanchez-Mateos P. J. Cancer Res. 2004; PubMed Scopus Google Scholar). cells with and in with or and upon cell from for and the was with or proteins van S. J.P. T. van R.A. F. J. Cell Biol. 1998; PubMed Scopus Google in the of of bound to with or and cells on with in and with primary and with with and a with cells with in with primary or with at the in the cells with primary by with and in a was used as control primary by of by both the of was Overexpression of E-cadherin in Melanoma to of of CXCR4 on melanoma cells confers invasiveness toward CXCL12 R.A. Longo N. F. Muijen G.N. Sanchez-Mateos P. J. Cancer Res. 2004; PubMed Scopus Google Scholar). these cells express of E-cadherin we its overexpression could influence melanoma cell invasion. We cells with E-cadherin and and high of E-cadherin compared with or that expressed experiments that CXCR4 and expression was in the E-cadherin Overexpression of E-cadherin on cells correlated with β-catenin and as well as with of these proteins at cell-cell and and E-cadherin with α-catenin at of p120ctn of and detected in and but high of this catenin found associated with E-cadherin on cells that p120ctn was by E-cadherin in these A of p120ctn was in E-cadherin in from the of E-cadherin molecules expressed on their E-cadherin with p120ctn on whereas it a in cells These results show that E-cadherin associates with their binding on the membrane of melanoma Expression of E-cadherin on and melanoma led to a inhibition of their CXCL12-promoted invasion across Matrigel and type I as compared with transfectant invasion invasiveness was directly on E-cadherin, as invasion of cells was when expression of this protein was by and when on both in the of CXCL12 or in its that impairment in invasion of E-cadherin was the of cell of the defective invasion of E-cadherin melanoma on Matrigel in that migration directionality toward CXCL12 which a the cell directionality on the was in in EMD, AMD, EMD, AMD, when we E-cadherin in adhesion to Matrigel or to collagen or we a impairment in their which was mediated by These suggest that a in cell toward CXCL12 associated with reduced adhesion by melanoma cells overexpressing E-cadherin for their impaired invasion in response to the of E-cadherin Melanoma to in CXCL12-promoted RhoA cell migration and invasion are to of the actin which is by Rho GTPases E. Marshall C.J. Nat. Rev. Cancer. 2002; 2: 133-142Crossref PubMed Scopus (1241) Google Scholar). melanoma cell invasion requires Rho activation R.A. Longo N. F. Muijen G.N. Sanchez-Mateos P. J. Cancer Res. 2004; PubMed Scopus Google Scholar), we whether E-cadherin overexpression in melanoma cells activation of these GTPases. that and defective RhoA activation in response to CXCL12 compared with E-cadherin activation of and a of and as by and when we expressed constitutively of RhoA in and melanoma invasion to CXCL12 was recovered to to by cells RhoA These results indicate that defective melanoma cell invasion to CXCL12 upon E-cadherin expression is on impaired RhoA activity on RhoA a the activation of this on E-cadherin melanoma A molecule in RhoA inactivation and is which RhoA J. R.A. Nature. PubMed Scopus Google Scholar, A.J. A.J. F. Hall A. Marshall C.J. C. J. PubMed Scopus Google Scholar). of p190RhoGAP has been to be associated with its S. J. Parsons J. Cell Biol. PubMed Scopus Google Scholar, H. M. J. Biol. 1998; Full Text Full Text PDF PubMed Scopus Google Scholar, Burridge K. Biol. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar), the N. M. Parsons Mol. Cell. Biol. 1998; PubMed Scopus Google Scholar). p190RhoGAP a of in and in and which was associated with increased RhoA cells to we detected in p190RhoGAP in it was to it in and to the that constitutively high in cells of p190RhoGAP led to recovery of RhoA activation by CXCL12 to to in p190RhoGAP in and cells activity by family as it was inhibited by the but with the control in with results the role of proteins in p190RhoGAP N. M. Parsons Mol. Cell. Biol. 1998; PubMed Scopus Google Scholar, C. M. F. T. Nature. PubMed Scopus Google Scholar, Parsons J.T. Mol. Cell. Biol. 1991; 11: PubMed Scopus Google Scholar, A. M.C. J. Cell Sci. 1999; PubMed Google Scholar). Furthermore, p190RhoGAP-RhoA was reduced in that of this protein was for its binding to investigate increased activity of p190RhoGAP on RhoA could the impairment in and we p190RhoGAP and in invasion toward CXCL12. The results that and invasion was recovered to to cells upon p190RhoGAP that increased activation of this protein in E-cadherin accounts for the reduction in invasion to inhibition of RhoA of p120ctn in RhoA and of Melanoma have that p120ctn overexpression results in inhibition of RhoA by a activity of p120ctn M.A. D.J. A.B. Nat. Cell Biol. 2000; 2: PubMed Scopus Google Scholar, Burridge K. B. J. Cell Biol. 2000; PubMed Scopus Google Scholar), and of this catenin with RhoA was reported both in and in vivo D. 2002; 129: Google Scholar, J. G. D. I. P. de A. M. Mol. Cell. Biol. 2007; PubMed Scopus Google Scholar). Furthermore, it has been that p120ctn and p190RhoGAP in E-cadherin complexes in to inhibition of RhoA activation M.A. J. A.B. Cell. 2006; Full Text Full Text PDF PubMed Scopus Google Scholar). investigate p120ctn is of p190RhoGAP-dependent impairment in RhoA activation and invasion in melanoma we whether these proteins on E-cadherin melanoma experiments with melanoma cells with control or p120ctn that p120ctn and p190RhoGAP to in and that of the of E-cadherin expression CXCL12 on melanoma p190RhoGAP in and cells was on as it in cells Furthermore, was in and cells p190RhoGAP-RhoA was on as it was in p120ctn cells and to a in p120ctn cell only on cells overexpressing E-cadherin, of p190RhoGAP was in and cells for p190RhoGAP was found as well as on cell where it with p120ctn on cells E-cadherin, p120ctn and p190RhoGAP only at cell membrane but at cell-cell Cell the membrane of p120ctn on and its with p190RhoGAP at this plasma membrane of p190RhoGAP and RhoA in which correlated with increased of these proteins on cell and used as for plasma membrane and these results indicate that p120ctn and p190RhoGAP of E-cadherin expression, and that overexpression of E-cadherin their on the cell which p190RhoGAP-RhoA to inactivation of this binding is for the of p190RhoGAP and we expressed in melanoma cells a E-cadherin that binding to p120ctn M.A. A.B. J. Cell Biol. 2000; PubMed Scopus Google Scholar). experiments that expression in cells led to a reduction in the of E-cadherin with p120ctn to to as compared with E-cadherin type that and expressed of cell E-cadherin of p120ctn and p190RhoGAP of E-cadherin expression in with results with cells of p190RhoGAP was in that is for of the reduced of RhoA bound to p190RhoGAP found in compared with which was associated with a of RhoA activation in the E-cadherin in with cells and to the of p120ctn in the impaired invasion toward CXCL12 by E-cadherin melanoma we and cells with control or p120ctn in Matrigel invasion p120ctn in their invasion to CXCL12 their RhoA activation by the chemokine A and cells a of RhoA activation and a recovery of invasion. with these we a decrease in E-cadherin cell expression These suggest that p120ctn invasion in E-cadherin melanoma by controlling p190RhoGAP-dependent RhoA or reduction of E-cadherin expression is frequently associated with acquisition of invasive in Expression of E-cadherin in is reduced at initial of melanoma (8Tang A. Eller M.S. Hara M. Yaar M. Hirohashi S. Gilchrest B.A. J. Cell Sci. 1994; 107: 983-992PubMed Google Scholar, 9Cowley G.P. Smith M.E. J. Pathol. 1996; 179: 183-187Crossref PubMed Scopus (42) Google Scholar, 10Hsu M. Andl T. Li G. Meinkoth J.L. Herlyn M. J. Cell Sci. 2000; 113: 1535-1542PubMed Google Scholar). of E-cadherin are found at advanced stages of the disease (9Cowley G.P. Smith M.E. J. Pathol. 1996; 179: 183-187Crossref PubMed Scopus (42) Google Scholar, 11Danen E.H. de Vries T.J. Morandini R. Ghanem G.G. Ruiter D.J. van Muijen G.N. Melanoma Res. 1996; 6: 127-131Crossref PubMed Scopus (94) Google Scholar, 12Silye R. Karayiannakis A.J. Syrigos K.N. Poole S. van Noorden S. Batchelor W. Regele H. Sega W. Boesmueller H. Krausz T. Pignatelli M. J. Pathol. 1998; 186: 350-355Crossref PubMed Scopus (105) Google Scholar), the that recovery of E-cadherin expression could influence the invasive of melanoma Both in and in vivo indicate that the chemokine receptor CXCR4 crucial in the invasion and metastasis of melanoma cells (18Murakami T. Maki W. Cardones A.R. Fang H. Tun Kyi A. Nestle F.O. Hwang S.T. Cancer Res. 2002; 62: 7328-7334PubMed Google Scholar, R.A. Longo N. F. Muijen G.N. Sanchez-Mateos P. J. Cancer Res. 2004; PubMed Scopus Google Scholar). this we have used the highly invasive melanoma cell which of E-cadherin, to investigate whether chemokine-stimulated melanoma cell invasion is upon overexpression of we show that E-cadherin melanoma have defective invasion toward CXCL12 chemotactic as a of impairment in cell migration directionality and in migration and adhesion was of increased cell-cell contacts as a of E-cadherin experiments that defective migration directionality in E-cadherin was of individual Furthermore, was a in cell response to as these of their activation in response to the Therefore, cell toward chemotactic stimuli led to migration and reduced invasion of E-cadherin melanoma of the impaired invasion that a defective of E-cadherin melanoma to RhoA in response to of increased activity of p190RhoGAP on this as well as a reduction in accounted for the inhibition in invasion. expression of a constitutively of RhoA or p190RhoGAP expression led to of E-cadherin melanoma transfectant invasion. These suggest that chemokine-stimulated RhoA activation to the cell response toward CXCL12 that results in migration and and the indicate that p190RhoGAP a role in controlling melanoma cell invasion. of p190RhoGAP has been with in its activation S. J. Parsons J. Cell Biol. PubMed Scopus Google Scholar, H. M. J. Biol. 1998; Full Text Full Text PDF PubMed Scopus Google Scholar, Burridge K. Biol. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar, A. M.C. J. Cell Sci. 1999; PubMed Google Scholar). Melanoma cells overexpressing E-cadherin of p190RhoGAP which was on the activity of in with their reported in the of the protein N. M. Parsons Mol. Cell. Biol. 1998; PubMed Scopus Google Scholar, C. M. F. T. Nature. PubMed Scopus Google Scholar, Parsons J.T. Mol. Cell. Biol. 1991; 11: PubMed Scopus Google Scholar, A. M.C. J. Cell Sci. 1999; PubMed Google Scholar). The for the increased most from E-cadherin in cell-cell contacts that activity at adherens junctions, as Burridge K. J. Biol. 2003; Full Text Full Text PDF PubMed Scopus Google Scholar). of p190RhoGAP was for its with as it was in melanoma a constitutively of RhoA Burridge K. J. Biol. 2003; Full Text Full Text PDF PubMed Scopus Google reported that with p190RhoGAP in E-cadherin Furthermore, of p190RhoGAP at is for actin L. Parsons J. Cell Sci. 2001; PubMed Google Scholar), a associated with RhoA with these the of p190RhoGAP for its binding to and inactivation of p120ctn is a E-cadherin binding that is in inhibition of RhoA activation by with this A.B. A. 2004; PubMed Scopus Google Scholar). Overexpression of E-cadherin in melanoma cells led to a on the cell whereas p120ctn a in we found that p120ctn was associated with p190RhoGAP both in and melanoma but cell membrane and of these proteins was in overexpressing Furthermore, we found of as well as in plasma membrane from E-cadherin from of p190RhoGAP at cell in both E-cadherin, and p190RhoGAP at cell membrane that E-cadherin on the cell p120ctn expression cell that a inhibition of RhoA activation by p120ctn influence this when p120ctn was in melanoma cells overexpressing E-cadherin, a recovery of RhoA activation to a large decrease in p190RhoGAP-RhoA and a of invasion was p120ctn or p190RhoGAP expression leads to recovery of RhoA activation in melanoma cells overexpressing E-cadherin, but only p190RhoGAP cells the invasion. results suggest that RhoA inactivation in these cells is to but p120ctn is for between the protein and the of p190RhoGAP in E-cadherin melanoma p120ctn or p120ctn binding to E-cadherin, as it in cells a E-cadherin of p190RhoGAP requires the of P. M. T. T. Mol. Cell. Biol. PubMed Scopus Google Scholar), a protein that directly with the of p190RhoGAP N. M. Parsons Mol. Cell. Biol. 1998; PubMed Scopus Google Scholar, J. J. 16: PubMed Scopus Google it is that of p190RhoGAP in melanoma cells is contributed by these results suggest a model for chemokine-stimulated invasion of melanoma cells on the of E-cadherin this protein is or expressed at activation in response to activity to Rho activation that invasion R.A. I. R. Sanchez-Mateos P. J. Cancer Res. 2006; 66: PubMed Scopus Google Scholar). is that this in the of a E-cadherin is expressed at high of p190RhoGAP is its with RhoA on the cell leads to RhoA chemokine-stimulated activity and in defective invasion toward the which is on impaired cell migration results indicate that is to stimulate or to p190RhoGAP-RhoA as it was reduced in in a of RhoA has been that when p120ctn is bound to E-cadherin on the cell it directly mediate inhibition of RhoA activation M.A. D.J. A.B. Nat. Cell Biol. 2000; 2: PubMed Scopus Google Scholar), and that p190RhoGAP this role in a and in M.A. J. A.B. Cell. 2006; Full Text Full Text PDF PubMed Scopus Google Scholar). the of p190RhoGAP in RhoA inactivation a cancer cell that this cell invasion toward results the that of melanoma cells at advanced stages of the disease could have reduced metastatic potency in response to chemotactic stimuli compared with cells lacking E-cadherin, that of its expression to melanoma in a skin E-cadherin expression led to of melanoma cell invasion into M. P. Herlyn M. J. Pathol. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar). of p190RhoGAP a to inhibition of RhoA activation and invasion. this a tumor role has been associated with p190RhoGAP A. S. C. S. K. H. 2000; PubMed Scopus Google Scholar, N. C. L. C. B. Genes Dev. 2003; PubMed Scopus Google Scholar). are to its in melanoma cell We de and A. for and We for with