Identification of genes involved in human urothelial cell-matrix interactions: implications for the progression pathways of malignant urothelium.
Interactions between epithelial cells and the extracellular matrix are central to tissue homeostasis and have a dynamic role in tissue remodeling and repair. Regulation of these pathways is balanced by positive and negative feedback elements, many of which have been implicated in the pathways of malignant progression. We have used differential display to identify genes that are up-regulated in normal human urothelial cells in response to exposure to extracellular matrix proteins (Matrigel) in vitro. This approach has identified genes that have key roles in cell-cell and cell-matrix interactions and that have been implicated in the progression of carcinomas of urothelial or other epithelial cell origins. One confirmed but unknown differentially expressed sequence was used to isolate a full-length gene, MIG-C4, from a human urothelial cDNA library. This gene was found to encode a novel urokinase plasminogen-activator receptor-like member of the Ly-6 family of glycosyl-phosphatidylinositol-anchored glycoproteins, and was identified as the human homologue of the rat metastasis-associated C4.4A gene. By in situ hybridization, MIG-C4 was expressed variably in normal urothelium and intensely in the tumor component of some noninvasive superficial lesions and in invasive and metastatic urothelial cancers. Thus, our approach has identified previously nonimplicated gene products involved in normal urothelium-matrix interactions that could be tumor-invasion or suppressor-gene targets in the development of invasive and metastatic tumor phenotypes.
Jack Birch Unit of Molecular Carcinogenesis, Department of Biology, University of York, United Kingdom.
B A
BA
Smith
W J
WJ
Kennedy
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Harnden
P J
PJ
Selby
L K
LK
Trejdosiewicz
J
J
Southgate
D000595:Amino Acid Sequence; D000818:Animals; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000378:metabolism; D002450:Cell Communication / Q000235:genetics / Q000502:physiology; D003094:Collagen; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D004338:Drug Combinations; D005109:Extracellular Matrix / Q000378:metabolism / Q000502:physiology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017403:In Situ Hybridization; D007682:Kidney Pelvis / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D007797:Laminin; D008969:Molecular Sequence Data; D011509:Proteoglycans; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D014407:Tumor Cells, Cultured; D014513:Ureter / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D014571:Urologic Neoplasms / Q000235:genetics* / Q000378:metabolism
D018076:DNA, Complementary; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen