Midkine Binds to Anaplastic Lymphoma Kinase (ALK) and Acts as a Growth Factor for Different Cell Types

Abstract

Midkine (MK) is a developmentally regulated, secreted growth factor homologous to pleiotrophin (PTN). To investigate the potential role of MK in tumor growth, we expressed MK in human SW-13 cells and studied receptor binding, signal transduction, and activity of MK. The MK protein stimulates soft agar colony formationin vitro and tumor growth of SW-13 cells in athymic nude mice, as well as proliferation of human endothelial cells from brain microvasculature and umbilical vein (HUVEC) in the low ng/ml range. MK binds to anaplastic lymphoma kinase (ALK), the receptor for PTN, with an apparent K d of 170 pm in intact cells, and this receptor binding of MK is competed by PTN with an apparent K d of ∼20 pm. Monoclonal antibodies raised against the extracellular ligand-binding domain of ALK inhibit ALK receptor binding of MK as well as MK-stimulated colony formation of SW-13 cells. Furthermore, MK stimulates ALK phosphorylation in WI-38 human fibroblasts and activates PI3-kinase and MAP kinase signal transduction in WI-38, HUVEC, neuroblastoma (SH SY-5Y) and glioblastoma (U87MG) cells that express the ALK protein. We conclude that MK can act as a growth, survival, and angiogenic factor during tumorigenesis and signals through the ALK receptor. Midkine (MK) is a developmentally regulated, secreted growth factor homologous to pleiotrophin (PTN). To investigate the potential role of MK in tumor growth, we expressed MK in human SW-13 cells and studied receptor binding, signal transduction, and activity of MK. The MK protein stimulates soft agar colony formationin vitro and tumor growth of SW-13 cells in athymic nude mice, as well as proliferation of human endothelial cells from brain microvasculature and umbilical vein (HUVEC) in the low ng/ml range. MK binds to anaplastic lymphoma kinase (ALK), the receptor for PTN, with an apparent K d of 170 pm in intact cells, and this receptor binding of MK is competed by PTN with an apparent K d of ∼20 pm. Monoclonal antibodies raised against the extracellular ligand-binding domain of ALK inhibit ALK receptor binding of MK as well as MK-stimulated colony formation of SW-13 cells. Furthermore, MK stimulates ALK phosphorylation in WI-38 human fibroblasts and activates PI3-kinase and MAP kinase signal transduction in WI-38, HUVEC, neuroblastoma (SH SY-5Y) and glioblastoma (U87MG) cells that express the ALK protein. We conclude that MK can act as a growth, survival, and angiogenic factor during tumorigenesis and signals through the ALK receptor. midkine anaplastic lymphoma kinase 2-[bis(2-hydroxyethyl)amino]ethanesulfonic acid CMV, cytomegalovirus extracellular domain extracellular signal-regulated kinase fluorescence-activated cell sorter fibroblast growth factor human umbilical vein endothelial cell(s) ligand-binding domain mitogen-activated protein kinase phosphate-buffered saline phosphatidylinositol 3-kinase pleiotrophin ribozyme Polypeptide growth factor expression is tightly regulated during development and in the adult organism, but it appears to be deregulated during the course of malignant transformation (1Cross M. Dexter T.M. Cell. 1991; 64: 271-280Abstract Full Text PDF PubMed Scopus (612) Google Scholar). Here we report on the potential role of the growth factor midkine (MK)1 in this process. MK is a member of the pleiotrophin (PTN)/MK family and was originally described as a retinoic acid-inducible, developmentally regulated, heparin-binding, neurotrophic factor (2Kadomatsu K. Huang R.P. Suganuma T. Murata F. Muramatsu T. J. Cell Biol. 1990; 110: 607-616Crossref PubMed Scopus (254) Google Scholar, 3Matsubara S. Tomomura M. Kadomatsu K. Muramatsu T. J. Biol. Chem. 1990; 265: 9441-9443Abstract Full Text PDF PubMed Google Scholar, 4Tomomura M. Kadomatsu K. Matsubara S. Muramatsu T. J. Biol. Chem. 1990; 265: 10765-10770Abstract Full Text PDF PubMed Google Scholar). MK is 50% homologous to PTN at the amino acid level and shares with PTN the genomic organization (5Lai S. Czubayko F. Riegel A.T. Wellstein A. Biochem. Biophys. Res. Commun. 1992; 187: 1113-1122Crossref PubMed Scopus (22) Google Scholar, 6Lai S. Schulte A.M. Wellstein A. Riegel A.T. Gene. 1995; 153: 301-302Crossref PubMed Scopus (8) Google Scholar, 7Uehara K. Matsubara S. Kadomatsu K. Tsutsui J. Muramatsu T. J Biochem. (Tokyo). 1992; 111: 563-567Crossref PubMed Scopus (80) Google Scholar) and predicted protein structure (reviewed in Refs.8Muramatsu T. Int. J. Dev. Biol. 1993; 37: 183-188PubMed Google Scholar and 9Bohlen P. Kovesdi I. Prog. Growth Factor Res. 1991; 3: 143-157Abstract Full Text PDF PubMed Scopus (65) Google Scholar). Physiologically, MK is highly expressed during midgestation in the brain and numerous other organs and is down-regulated at birth. In the adult, MK shows a very restricted pattern of expression with the highest transcript levels in the intestine and low levels in the cerebellum, thyroid, kidney, bladder, lung alveoli, colon, stomach, and spleen (reviewed in Refs. 10Tsutsui J. Kadomatsu K. Matsubara S. Nakagawara A. M. S. Muramatsu T. Res. 1993; Google Scholar and T. S. Res. Google Scholar). MK during development and in the M. Muramatsu T. Muramatsu M. I. 1995; PubMed Google Scholar) as well as in K. M. T. Muramatsu T. Kadomatsu K. J Biochem. (Tokyo). 1995; PubMed Scopus Google Scholar). in vitro cell and the expression pattern of MK in the it was that MK during an of brain development and on a in restricted In from MK the of K. T. Muramatsu Muramatsu T. M. J. Google Scholar). Furthermore, MK of cells as K. T. Kadomatsu K. Muramatsu T. M. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google T. T. Muramatsu A. S. Muramatsu T. Biochem. Biophys. Res. Commun. PubMed Scopus Google and M. Kadomatsu K. Muramatsu S. S. K. S. M. T. M. Muramatsu T. J. PubMed Scopus Google Scholar). that MK a role in and of tumor cells. during in the adult brain as Muramatsu Muramatsu T. Biochem. Biophys. Res. Commun. 1993; PubMed Scopus Google Scholar) during S. M. T. Tsutsui J. S. Muramatsu T. M. Res. Dev. Res. PubMed Scopus Google the expression of midkine and it that this the of a S. M. T. Tsutsui J. S. Muramatsu T. M. Res. Dev. Res. PubMed Scopus Google Scholar). of that MK as an angiogenic In the MK is by this with angiogenic activity in this J. Cell 1995; Google Scholar). Furthermore, MK is to and activity in endothelial cells S. Muramatsu Muramatsu T. J. Biol. Chem. 1995; Full Text Full Text PDF PubMed Scopus Google Scholar, S. Google that MK a role in and The growth factor PTN is in a of we and that PTN can as a tumor growth factor Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar, S. A. 1993; PubMed Scopus Google Scholar) and can endothelial cell proliferation and Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar, J. M. Biochem. Biophys. Res. Commun. 1991; PubMed Scopus Google Scholar, K. J. F. P. M. M. J. Growth PubMed Scopus Google Scholar). We of PTN to that PTN can be the growth factor for growth, and in F. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text PDF PubMed Google F. Schulte A.M. Wellstein A. S. A. PubMed Scopus Google Scholar). PTN, MK expression is in the of human A. J. Muramatsu T. A. Res. 1995; Google PubMed Scopus Google Scholar) and lung and J. Cell Biol. 1993; PubMed Scopus Google J. Kadomatsu K. Matsubara S. Nakagawara A. M. S. Muramatsu T. Res. 1993; Google Scholar, K. Tsutsui J. S. Kadomatsu K. M. T. Muramatsu T. J. Res. 1995; PubMed Scopus Google T. S. Res. Google a of cell J. Kadomatsu K. Matsubara S. Nakagawara A. M. S. Muramatsu T. Res. 1993; Google Scholar, PubMed Scopus Google Scholar, J. Cell Biol. 1993; PubMed Scopus Google Scholar, M. T. T. Muramatsu T. J. 1993; Google Scholar). is that midkine expression is very restricted in adult To levels of midkine expression with a in and T. S. Res. Google Scholar, A. J. Muramatsu T. A. Res. 1995; Google Scholar, K. A. Kadomatsu K. K. Muramatsu T. T. PubMed Scopus Google Scholar). midkine levels in of a of midkine level S. A. K. M. K. M. S. T. Muramatsu Kadomatsu K. Muramatsu T. J. PubMed Scopus Google Scholar). Furthermore, in of and lung midkine levels at I. this expression with the very restricted expression pattern of MK in we to MK expression tumor growth and as an We the human MK a expression of the and cells that express and the MK protein. secreted MK stimulates the proliferation of human umbilical vein and human brain endothelial cells as well as the growth of SW-13 cells in soft Furthermore, cells in soft agar and in athymic nude The of of MK of the of a well MK receptor that can the growth factor signal K. T. Kadomatsu K. Muramatsu T. M. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, T. Kadomatsu K. T. K. M. Muramatsu T. PubMed Scopus Google Scholar, S. M. J. A. M. P. M. J. Cell. Biol. PubMed Scopus Google Scholar, T. T. M. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, M. J. Cell Biol. PubMed Scopus Google Scholar, K. S. S. Muramatsu T. Biochem. Biophys. Res. Commun. PubMed Scopus Google Scholar, PubMed Scopus Google Scholar, J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). on the by of anaplastic lymphoma kinase as a receptor for pleiotrophin A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google we the that ALK be a receptor for the PTN family MK. Here we that MK binds to ALK and MK and PTN for binding to Furthermore, ALK receptor binding of MK as well as colony formation of SW-13 cells by antibodies to the extracellular ligand-binding domain of ALK A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). in cell we signal transduction of MK and brain endothelial cells of P. and of as from the and in with umbilical vein endothelial cells (HUVEC) from and cells a of of The other cell from and in with the human MK as an and was a of A. M. A. P. J. Biochem. Biophys. Res. Commun. 1992; PubMed Scopus Google Scholar). The of the MK and of the of the was from low and the of the expression Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar, F. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text PDF PubMed Google Scholar). The of the MK the during the process. The for an of was for and and cells the as described Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar). cells in the of of to cell cell by cell of cells to of and in in the of the growth of an and for MK protein expression by a protein The of ALK cells was described A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). The and of cells that express described very A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). In ribozyme expression that the ALK and to cells of a of cells, we that the of ALK expression is by a in the of the cells to Furthermore, the of ALK to tumor growth and in the A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). of the cell from that with a of ALK by was in the to the role of ALK for MK signal of for by SW-13 cells was and and the with a of of and in as described for the of PTN A. J. Riegel A.T. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar). growth of SW-13 cells in soft agar as described by cells in on a of in A. J. Riegel A.T. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar, A. P. Cell Growth 1990; Google Scholar). In the of SW-13 cells to growth of SW-13 was in a of cells was to to of the this of cells was with of was to a was of a SW-13 cells as of growth from the cells. in the an with a The for colony was in The colony formation by cells was as and was in the of to on the umbilical vein endothelial cells and human brain endothelial cells in at cells, In of growth from from cells as to the ng/ml as a the cells and in a with and the was at athymic nude with cells in of and for tumor formation as described Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar, A. F. S. J. 1991; PubMed Scopus Google Scholar, F. Wellstein A. J. Biol. Chem. Full Text PDF PubMed Google Scholar). The as described by of cells by of the from A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). cells with the human ALK an as and cells, A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). antibodies to the ALK by of with the as a protein. was described and was to antibodies to the A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). protein in cells was for the of and The extracellular domain of ALK was expressed as a secreted protein in SW-13 cells by the T. J. T. S. T. PubMed Scopus Google Scholar) the expression with a the signal at the was and expressed in SW-13 cells, and the secreted protein was from the cell To cells antibodies of spleen cells from an a signal with the protein was for with cells on a of and J. PubMed Scopus Google Scholar). The ALK was to by for the of The antibodies in the from of and and for as and The at a for the in cell of cells for with the ALK expression described A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar) with from the with in in intact cells in of for at with cells in of a of for at with cell in in for at cell in to a of was to the of The of and was as described S. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (65) Google Scholar) antibodies from Cell The for was a from a from was of antibodies raised against of The and the from S. from cells in for and in for and SW-13 cells as a cell to of MK cells express ALK and to the growth factor pleiotrophin A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). We cells with a human MK with the expression and cell for from cells and with a to that during the of PTN A. J. Riegel A.T. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar). the from of cells MK and of of the cell that of cell secreted of MK MK as a we that and and of of MK was in the of SW-13 cells, with the of of the MK In the the expression for MK was during the of the expression the and the was is for a of cells for MK be expressed in but We of the SW-13 cell in in vitro to the of MK. In the of the of colony formation in soft agar of SW-13 cells was as an of growth factor cells in soft agar in athymic nude by growth as A. P. Cell Growth 1990; Google F. Wellstein A. J. Biol. Chem. Full Text PDF PubMed Google Scholar) PTN Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar, A. J. Riegel A.T. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar) that to from the cells. The cell to be as cells on the of with a soft agar that the cells from the cells on the of the described of of the cell secreted MK MK was in of the cell and we that the cell colony formation of the SW-13 cells. the we a in the of and at a for the other cells The cell that MK to soft agar colony formation of the cells. with MK from cells the and MK SW-13 colony formation that the growth PTN, can proliferation of endothelial cells in to SW-13 cells Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google and we MK in this this we from of the cell as with a MK was and the MK we this in the endothelial cell proliferation shows a of MK on The highest of MK in the was as ng/ml on a of the of MK 50% of the of that proliferation of the cells brain endothelial cells a to MK of MK was of the of cells. We conclude from that MK is a for endothelial cells in to activity on SW-13 cell colony In this MK shows an activity that is to PTN, of MK to PTN to be for a of endothelial cell proliferation K. F. J. J. Prog. Growth Factor Res. 1995; Full Text PDF PubMed Scopus Google Scholar). be a in the growth to well in the for of the family J. A. J. M. Cell. Biol. 1990; PubMed Google Scholar). of of MK during the with to We that of SW-13 cells with a PTN expression cells in athymic nude Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar). MK a activity as PTN in we expression of MK SW-13 cells in We of the as with a and SW-13 cells for We as as in the the tumor in that with SW-13 SW-13 in with with SW-13 cells Riegel A.T. Wellstein A. J. Biol. Chem. 1992; Full Text PDF PubMed Google Scholar). that MK was expressed in the from the cells and we from this that MK expression can tumor growth in MK and PTN to the we MK binds to the kinase receptor by as a receptor for PTN A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). We an that for PTN binding to We studied MK by of cells for binding to cells with the ALK an in the MK binds to ALK expressed in cells with an d of 170 is a for PTN A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). of MK to PTN is in a in To that MK binds to the receptor as PTN, we a of We and competed binding to cells by MK. in MK the binding of to Furthermore, a of PTN for ALK binding an apparent K d of ∼20 PTN in with d for PTN binding to the ALK A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). this of we conclude that MK and PTN to the with To the role of and to an that this we with a protein that the of ALK A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar) and cell from the spleen of the of the for the ALK protein was as a secreted protein in SW-13 cells to that the antibodies the In a of we the antibodies the ALK receptor expressed on the cell We cells that with an ALK expression and of cells to cell shows of the antibodies that the ALK protein on the cell of cells, a was to and cells. The antibodies binding of to cells by the the MK binding to ALK of the SW-13 cells express ALK and protein at low levels A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). The expression of MK PTN to the expression of ALK in cells To the role of ALK for MK-stimulated colony formation of SW-13 cells in soft MK was and with the of the antibodies the MK a of colony formation by on the other was by the antibodies the of the antibodies for MK through the antibodies colony formation of SW-13 cells MK by the The in the is of the by MK expression in the cells in to the of MK in the in with the antibodies the that MK binds to ALK and this receptor to cell for ALK and we a the of cells to PTN and the of ALK A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). The in expression that in the cell cells as well as cells express of ALK protein of ALK was in of the cell and and at levels in endothelial cells In WI-38 human fibroblasts the ALK protein as a a pattern that was by in human fibroblast glioblastoma cells express ALK levels that by A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar) and by of ALK in cells by signal transduction of PTN by in cells A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar) and in a of ALK protein The signal transduction of MK in cells is described the human neuroblastoma cell the highest ALK protein expression the cell of MK on in and ALK cells. cells with an ribozyme A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). ALK and protein was by in the ALK cells. with of MK cell by and by as from that PTN activates phosphatidylinositol 3-kinase and MAP kinase and ALK as a receptor A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, S. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (65) Google Scholar, A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). we that MK binds to we the of MK on cells that express ALK Refs. A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). We the WI-38 fibroblast cell and that phosphorylation was MK the in phosphorylation was In endothelial cells in MK proliferation MK a in phosphorylation and a in a signal in cells cells to be to MK T. T. S. Muramatsu T. Biochem. Biophys. Res. Commun. PubMed Scopus Google we the of MK on the human neuroblastoma cell and a in phosphorylation and a in phosphorylation in to the MK that MK can and in a very to the other family PTN S. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (65) Google Scholar). We the WI-38 human fibroblasts to ALK phosphorylation in to we the highest in the signal transduction with cells ALK was from and from MK-stimulated cells and with of MK with an and the for of the in shows that MK ALK phosphorylation and that this is by the but by the to the that MK signals the ALK receptor. To the of ALK for MK signal transduction, we a of MK on phosphorylation in cells that with a a ribozyme against the ALK cells ALK and protein levels A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar and and and phosphorylation is to with PTN, MK is to phosphorylation of ALK is that in with the PTN and MK signals of phosphorylation in the cells a kinase the growth factor receptor was by the of ALK levels A. K. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). in the cells is and by the ALK by MK We conclude from signal transduction that MK can and ALK at a and to a in cell The expression of MK in human and tumor cell and to endothelial cell vitro and tumor growth in the that MK can an role in human J. Kadomatsu K. Matsubara S. Nakagawara A. M. S. Muramatsu T. Res. 1993; Google T. S. Res. Google Scholar, A. J. Muramatsu T. A. Res. 1995; Google Scholar, PubMed Scopus Google Scholar, K. Tsutsui J. S. Kadomatsu K. M. T. Muramatsu T. J. Res. 1995; PubMed Scopus Google Scholar, K. A. Kadomatsu K. K. Muramatsu T. T. PubMed Scopus Google Scholar, M. S. M. Muramatsu T. Kadomatsu K. PubMed Scopus Google Scholar). shows that MK growth to the SW-13 cell in a and we this to the ALK expression in cells A. A. I. A. Riegel A.T. Wellstein A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). In a in cells MK expression to an of in soft agar K. M. S. Muramatsu Muramatsu T. J. 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