INCREASED REACTIVE OXYGEN SPECIES PRODUCTION BY ALVEOLAR MACROPHAGES FROM MALIGNANT LOBE OF LUNG-CANCER PATIENTS

Alveolar macrophages (AMs) may contribute to inflammation in multiple ways, including the release of reactive oxygen species (ROS) such as s uperoxide anion (O-2(-)) and hydrogen peroxide (H2O2). This provides a basis for a plausible and testable hypothesis by which inflammation a nd the disease might be related; that is, the levels of ROS generated by inflammatory phagocytes might be dependent upon the type of disease . Alveolar macrophages were prepared from 25 lung cancer patients, 58. 7+/-7.51 years of age (mean+/-SD). Alveolar macrophages from 12 patien ts, 45.3+/-14.6 years of age, with nonmalignant lung diseases were als o studied. Production of oxygen radical species was higher in AMs from the malignant lobe of lung cancer patients than in those from the dis ease-free lobe. However, the levels in AMs from the disease-free lobe were comparable to the levels in AMs from patients with nonmalignant l ung diseases. There was an increase in hydrogen peroxide formation in the cells from malignant lobe of lung cancer patients compared with th at in those from the disease-free lobe (38.4+/-4.16 vs, 26.9+/-2.94 nm ol/mg). The formation in the cells from patients with nonmalignant lun g diseases was found to be 18.0+/-1.19 nmol/mg protein, In the presenc e of phorbol-12-myristate-13-acetate, the formation in the cells from malignant lobe of lung cancer patients increased compared with that fr om the disease-free lobe (63.9+/-7.65 vs. 34.3+/-4.95 nmol/mg protein) , and the formation in the cells from patients with nonmalignant lung diseases was 42.5 +/- 5.03 nmol/mg protein. The enormous increase in O -2(-) and H2O2 production in malignancy needs further investigation fo r its diagnostic and prognostic values.