RESUMO
BACKGROUND: The aim of this study was to define the alterations in the activity of alcohol dehydrogenase (ADH) isoenzymes and aldehyde dehydrogenase (ALDH) in normal and cancerous lung cells. MATERIALS AND METHODS: Lung tissues were taken from 36 patients during surgical resection of cancer. The activities of tested enzymes were measured by spectrofluorometric method (ADH I, ADH II, total ALDH) and photometric method (ADH III, ADH IV, total ADH). RESULTS: The activities of class II and III ADH were significantly lower in lung cancer cells compared to histologically normal lung tissue. CONCLUSION: Reduced activity of isoenzyme class II ADH may affect disorders in retinoic acid biosynthesis, leading to its deficit. Lower ADH III activity may result in depletion of glutathione, and in initiation of oxidative stress, leading to cancer progression. These data suggest that alterations in ADH isoenzyme activities can contribute to carcinogenesis in human lungs.
