SEARCH FOR MUTATIONS AND EXAMINATION OF ALLELIC EXPRESSION IMBALANCE OF THE P73 GENE AT 1P36.33 IN HUMAN LUNG CANCERS

We examined 61 lung cancer cases to determine whether alterations of p 73, a novel monoallelically expressed p53-like molecule, may be involv ed in the pathogenesis of lung cancer, Allelic loss at the p73 locus a t 1p36.33 mas observed in 42% (11 of 26 informative eases), and squamo us cell carcinoma tended to carry this lesion most frequently, Somatic mutations in the p73 gene itself, however were not detected, despite our extensive search, We found interindividual difference in the allel ic expression of p73 in normal lung, as well as intertissue variance, even within the same individual, hut preferential loss or the expresse d allele appeared to be an unlikely mechanism for p73 inactivation, Th is study, consequently, suggests the presence of an as yet unidentifie d tumor suppressor gene or genes within the subtelomeric region of 1p, warranting further studies aimed at its isolation.