Novel regions of allelic deletion on chromosome 18p in tumors of the lung,brain and breast

Lung cancer is now the number one cause of cancer death for both men and wo men. An age-adjusted analysis over the past 25 gears shows that in women sp ecifically, lung cancer incidence is on the rise. It is estimated that 10-2 0 genetic events including the alteration of oncogenes and tumor suppressor genes will have occurred by the time a lung tumor becomes clinically evide nt. In an effort to identify regions containing novel cancer genes, chromos ome 18p11, a band not previously implicated in disease, was examined for lo ss of heterozygosity (LOH). In this study, 50 matched normal and NSCLC tumo r samples were examined using sis 18p11 and one 18q12.3 PCR-based polymorph ic markers. In addition, LOH was examined in 29 glioblastoma pairs and 14 p aired breast carcinomas. This analysis has revealed potentially two regions of LOH in 18p11 in up to 38% of the tumor samples examined, The regions of LOH identified included a 2 cm area between markers D18S59 and D18S476, an d a more proximal, 25 cm region of intermediate frequency between D18S452 a nd D18S453, These results provide evidence for the presence of one or more potential tumor suppressor genes on the short arm of chromosome 18 which ma y be involved in NSCLC, brain tumors and possibly breast carcinomas as well .