ANALYSIS OF THE NEUROFIBROMATOSIS TYPE-2 GENE IN DIFFERENT HUMAN TUMORS OF NEUROECTODERMAL ORIGIN

The autosomal dominant syndrome neurofibromatosis type 2 (NF2) is char acterized by the development of bilateral vestibular schwannomas, meni ngiomas, ependymomas and gliomas. The NF2 gene, recently isolated from chromosome 22, is mutated in both sporadic and NF2 tumors such as sch wannomas, meningiomas and ependymomas. Mutations of the gene have been described not only in the neoplasms usually associated with NF2, but also in 30% of the melanomas and 41% of the mesotheliomas analyzed. In particular, the finding of mutations in melanomas supports the hypoth esis that the NF2 gene is involved in the genesis of several tumor typ es that arise from the embryonic neural crest. In this study we examin ed, by single-strand conformation polymorphism (SSCP) analysis, 41 tum ors of the central nervous system (11 schwannomas and 30 gliomas), 19 melanomas and 15 Merkel cell carcinoma specimens for mutations in the coding sequence of the NF2 gene. We found three inactivating mutations of the NF2 gene in schwannomas. No alterations of the gene were detec ted by SSCP analysis of the other tumors. These results confirm the ro le of NF2 in pathogenesis of schwannomas, but do not define its signif icance in the genesis of the other neuroectodermal tumors studied.