MICROSATELLITE INSTABILITY IS INFREQUENT IN NEUROBLASTOMA

Neuroblastoma (NB) is a childhood cancer of the autonomic nervous syst em. The molecular pathology of NB is not yet well understood. Both amp lification of the proto-oncogene N-myc and loss of heterozygosity of s everal chromosomal loci occur in NB, representing genetic instability. In this study, we examined another type of genetic instability, micro satellite instability. Five chromosomal loci known to exhibit this alt eration in colon, gastric, and pancreatic cancers were used in a PCR-b ased assay to examine 30 matched normal and tumor DNAs, which included all stages of tumor progression. Among these 30, only 2 (7%) manifest ed microsatellite instability. There was no correlation between the oc currence of microsatellite instability and the amplification of the N- myc gene. These data show that microsatellite instability is infrequen t in neuroblastoma tumors.