Am. J. Respir. Crit. Care Med., Vol 152, No. 4, 10 1995, 1374-1378.
Analysis of K-ras gene mutations in malignant and nonmalignant endobronchial tissue obtained by fiberoptic bronchoscopy
NC Clements Jr, MA Nelson, JA Wymer, C Savage, M Aguirre and H Garewal
Department of Internal Medicine, University of Arizona, Tucson, USA.
Using polymerase chain reaction DNA amplification, we identified K-ras
oncogene mutations in bronchial biopsies obtained from patients undergoing
bronchoscopy for clinical indications. We hypothesized that these mutations
would be found in a field encompassing malignant and nonmalignant tissues
in patients with pulmonary carcinomas, and also possibly in tissue from
some patients who smoked but did not have pulmonary malignancy. We found
K-ras mutations in endobronchial biopsies from nine of 22 patients (41%)
with carcinoma of the lung. In five of these patients, mutations were found
in both malignant and nonmalignant specimens. In two instances, mutations
were found only in the neoplastic tissue, and in two cases mutations were
present only in the nonmalignant tissue. Furthermore, we identified two
patients with K- ras mutations among seven patients in whom no clinical
malignancy was apparent. Our data suggest that some oncogene activations
may occur over a broad area in smokers with and without malignancy, and
they imply that K-ras mutations may serve as surrogate markers for
malignant potential.
