Loss of heterozygosity on the long arm of chromosome 11 in nasopharyngeal carcinoma.

Loss of heterozygosity (LOH) on the long arm of chromosome 11 had been reported in many types of solid tumors. In this study, we investigated the LOH patterns of chromosome 11 on 52 primary nasopharyngeal carcinomas using 10 microsatellite polymorphic markers. The results revealed that 28 of the 52 cases (53.8%) demonstrated LOH on at least one of the nine 11q microsatellite loci studied. The highest frequencies of LOH were found at the two loci D11S2000 (36.1%) and D11S934 (34.5 %), both located at 11q22-24. Two distinct regions of deletion were found at 11q, with the first one defined by INT-2 and D11S900 at 11q13.3-22, and the second region located between D11S2000 and D11S934 at 11q22-24. The two deletion regions overlap with the common areas of deletion reported in other tumor types. This suggests the presence of multiple putative tumor suppressor genes on chromosome 11q that may play a role in the development of nasopharyngeal carcinomas.