title: Thy-1 as a negative growth regulator in ras-transformed mouse fibroblasts.
abstract: To identify molecules on the cell surface involved in negative growth regulation, we assumed that their amounts would be reduced after malignant transformation. We analyzed several proteins by fluorescence-activated cell sorter in mouse NIH 3T3 and its transformed cell lines. Surprisingly, the amount of Thy-1, a cell surface glycoprotein anchored in the cell membrane by a glycophosphatidyl inositol linkage, was significantly decreased in the transformed NIH 3T3 lines, especially in ras-transformed NIH 3T3 lines. The malignant properties of clones of NIH 3T3 transformed by Kirsten murine sarcoma virus have a good correlation not only with the high amount of RAS proteins but also inversely with the amount of Thy-1. NIH 3T3 subpopulations lacking Thy-1 exhibit more susceptibility to the induction of colony-forming ability in soft agar by Kirsten murine sarcoma virus than the Thy-1-positive populations. Finally the transfection of Thy-1 complementary DNA to the ras-transformed NIH 3T3 significantly inhibits the colony formation in soft agar as well as the tumor formation in nude mice. Our results suggest that Thy-1 has negative effects on the anchorage-independent growth of ras-transformed NIH 3T3 cells.
authors.affiliation: Aging Process Research Laboratory (Frontier Research Program), Institute of Physical and Chemical Research (RIKEN), Ibaraki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sugimoto
authors.forename: Y
authors.initials: Y
authors.lastname: Ikawa
authors.forename: H
authors.initials: H
authors.lastname: Nakauchi
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000235:genetics / Q000502:physiology*; D015152:Blotting, Northern; D015153:Blotting, Western; D002455:Cell Division; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000378:metabolism / Q000473:pathology*; D002472:Cell Transformation, Viral; D011905:Genes, ras; D051379:Mice; D015689:Oncogene Protein p21(ras) / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D018800:Thy-1 Antigens; D014162:Transfection
chemical_list: D000954:Antigens, Surface; D012333:RNA, Messenger; D018800:Thy-1 Antigens; D015689:Oncogene Protein p21(ras)