GAC1, A NEW MEMBER OF THE LEUCINE-RICH REPEAT SUPERFAMILY ON CHROMOSOME BAND 1Q32.1, IS AMPLIFIED AND OVEREXPRESSED IN MALIGNANT GLIOMAS

We have used two-dimensional electrophoresis of enzyme-digested genomi c DNA to identify a novel gene GAC1, which maps at 1q32.1 and which is overexpressed in malignant gliomas in which it is amplified. GAC1 enc odes a protein which belongs to the leucine-rich repeat superfamily. A mplification and overexpression of GAC1 was demonstrated in two of eig ht tumors where amplifications were previously evidenced by comparativ e genomic hybridization (one glioblastoma multiforme and one anaplasti c astrocytoma), and in one of eight unselected glioblastomas multiform e. GAC1 exhibits sequence homology with other proteins which function as cell-adhesion molecules or as signal transduction receptor and is a likely candidate for the target gene in the 1q32.1 amplicon in malign ant gliomas.