The effect of two BRM promoter variants on the risk of stage I/II upper aerodigestive tract cancers.

10522 Background: BRM is a key subunit of the chromatin remodeling complex SWI/SNF and a putative tumor suppressor gene that is silenced in 15-20% of many solid tumors (PMID 15722796). Evidence suggests that it is epigenetically regulated, as two BRM promoter insertion variants (BRM-741 and BRM-1321) may lead to gene silencing by recruiting histone deacetylases. The presence of both homozygous BRM-741 and BRM-1321 highly correlate with loss of BRM expression and function in lung tumors, while increasing smoking-related lung cancer by two-fold (PMID 21478907). Also, the pharmacologic reversal of epigenetic changes of BRM offers a potential novel therapeutic approach (PMID 21478905). We assessed whether these BRM variants are associated with the risk of upper aerodigestive tract cancers, focusing on Stage I/II tumors that would most benefit from new screening and prevention strategies. Methods: BRM was genotyped by qPCR using TaqMan probes. 1,008 controls were matched to 595 cases by frequency distribution ...