IDENTIFICATION OF MICROSATELLITE INSTABILITY PHENOTYPE IN MENINGIOMAS

To better understand the molecular mechanisms responsible for meningio ma tumorigenesis we previously utilized subtractive hybridization prot ocols to identify genes the expression or structure of which is altere d in these common brain tumors. Here we show that a CA dinucleotide re peat element present in one complementary DNA isolated by this approac h has undergone a contraction in size in a meningioma cell line. Exten sion of this initial observation has revealed widespread genetic alter ations affecting simple repeat sequences in this and other meningiomas . These data indicate that genetic instability may play a previously u nrecognized role in the etiology of meningiomas.