Lack of neurofibromatosis type 2 gene promoter methylation in sporadic vestibular schwannomas.

<i>Background:</i> Vestibular schwannomas (VS) are benign tumors of the nervous system that are usually sporadic but also occur in the inherited disorder neurofibromatosis type 2 (NF2). In VS, losses of chromosomal material and mutations of the NF2 gene have been established to be causative. For a subset of VS without detectable gene alterations, promoter inactivation by hypermethylation has been suggested. However, published data are very limited and contradictory. <i>Methods:</i> We analyzed NF2 gene promoter methylation in 35 sporadic VS by methylation-specific PCR. <i>Results:</i> Twenty-three of the tumors were informative, showing no promoter methyl…