[Immunohistological demonstration of developmental protein GP68 in human tumor and embryonic tissues]

A developmental protein GP68 is known to appear stage-specifically in the developmental mouse brain. The expression of GP68 in tissues of 265 various human tumors and of 2 human embryos was examined immunohistologically using specific anti-GP68 rabbit antisera. Generally, endodermal, neural, and germ cell tumors were most frequently positive, while mesenchymal tumors were mostly and ectodermal tumors were intermediate. Anti-GP68 also gave positive reactions with some of non-neoplastic cells of cancer patients generally to lesser extents than neoplastic cells. Muscle and bone tissues of a 4-week-old embryo were weakly positive. Some tumors that were negative for CEA and AFP were strongly positive for GP68. The expression of GP68 in human tumor cells may represent an abnormal cellular gene-expression associated with the neoplastic change of the cell.