ISOLATION OF A NOVEL GPI-ANCHORED GENE SPECIFICALLY REGULATED BY P53 - CORRELATION BETWEEN ITS EXPRESSION AND ANTICANCER DRUG-SENSITIVITY

We have identified a novel gene inducible by wild-type p53. A signific ant correlation between expression of this gene and p53 status in cell s derived from esophageal cancers indicated that this gene is likely t o be specifically regulated in a p53-dependent manner. As the predicte d amino acid sequence showed a high degree of homology to the family o f glycosyl-phosphatidylinositol (GPI)-anchored membrane proteins, we t ermed this gene GML (GPI-anchored molecule-like protein). Introduction of GML cDNA suppressed the growth of esophageal cancer cells in cultu re. A correlation between the presence of GML expression and the sensi tivity of esophageal cancer cells to anti-cancer drugs implied that th e gene product plays a significant role in the apoptotic pathway or ce ll-cycle regulation induced by p53 after DNA damage.