Characterization of a malignant phenotype-associated cell surface glycoprotein common to various human tumor cells and preferentially expressed on adenocarcinoma of the lung.
Since both the liver and lung are derived from the endoderm, common antigens may appear on both tissues during malignant transformation. In an attempt to delineate cell surface alterations associated with the neoplastic transformation of these tissues, we have produced a library of monoclonal antibodies against a human hepatoma cell line termed FOCUS. One of these monoclonal antibodies, designated AF-10, recognized an antigen preferentially expressed on human lung adenocarcinoma cells, both in vitro and in vivo. This antigen has been characterized using Western immunoblot analysis and immunoprecipitation from surface-iodinated or metabolically labeled cells. The mature antigen is a cell surface glycoprotein with a core polypeptide with a molecular weight of 75,000 bearing N-glycosylation units. This protein migrates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis with an apparent molecular weight of 100,000-115,000 in reducing conditions and Mr 115,000-130,000 in nonreducing conditions. The epitope recognized by monoclonal antibody AF-10 is borne by the core protein. This antigen is shed from the cell surface and was identified in the culture supernatant from lung adenocarcinoma cell lines. Studies of the biodistribution of the AF-10 antigen showed that it was also expressed at low levels in normal human small intestine and kidney. The AF-10 monoclonal antibody may be useful for the study of the antigen expression between normal lung and the transformed phenotype.
Motté
P
P
Molecular Hepatology Laboratory, Massachusetts General Hospital, Charlestown 02129.
Takahashi
H
H
Ozturk
M
M
Wilson
B E
BE
Wands
J R
JR
D000230:Adenocarcinoma / Q000276:immunology*; D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000032:analysis*; D000954:Antigens, Surface / Q000032:analysis*; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D008175:Lung Neoplasms / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D010641:Phenotype; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D006023:Glycoproteins