ALLELIC LOSS ON THE SHORT ARM OF CHROMOSOME-11 IN NON-SMALL-CELL LUNG-CANCER

Forty-eight samples of primary non-small-cell lung cancer (NSCLC) and normal tissue from the same patients were analyzed for allelic deletions on chromosome 11p. Five polymorphic loci were assessed to determine the incidence of 11p sequence deletions and to define hot-spots of deletions. Information was obtained from all patients in at least one locus. Our data show that the deletions observed were not randomly scattered over the short arm of chromosome 11. Rather, 2 hot-spots of deletions were observed: one in the area of the genes for catalase and beta-FSH corresponding to band 11p13, the other close to the IGF-11 locus corresponding to band 11p15. A high incidence of loss of heterozygosity (LOH) was found with the probe for catalase (21/29), a locus flanking the centromeric region of the Wilms' tumor locus. Most of the samples exhibiting LOH of one or more of the alleles analyzed remained heterozygous for at least one other chromosome 11p allele. Furthermore, duplication of the intensity of the remaining allele was rarely observed. Our results indicate that LOH on the short arm of chromosome 11 is a common event in NSCLC and that the chromosomal region containing the Wilms' tumor locus is most commonly involved.