CAPSAICIN-RESPONSIVE NADH OXIDASE ACTIVITIES FROM URINE OF CANCER-PATIENTS

NADH oxidases of low specific activities from urine of cancer patients were found to be inhibited or stimulated by the vanilloid capsaicin ( 8-methyl-N-vanillyl-6-noneamide). Similar activities, inhibited or sti mulated by capsaicin, were reported previously for sera of cancer pati ents but not for sera of normal volunteers or for patients with disord ers other than cancer. Like those from sera, the activities from urine were resistant to heat and to digestion with proteinase K. Two differ ent fractions with capsaicin-responsive NADH oxidase activities were o btained by FPLC, One fraction in which the 33-kDa band was the major c omponent exhibited NADH oxidase activity stimulated by capsaicin. Anot her fraction in which 66-kDa and 45-kDa bands were major components ex hibited NADH oxidase activities inhibited by capsaicin. A monoclonal a ntibody generated to a ca 34-kDa form of the NADH oxidase from sera re acted with a urine protein of a ca 33-kDa band in the capsaicin-stimul ated fraction. The 33-kDa protein was of low abundance and was estimat ed to be present in amounts between 5 and 100 mu g/L, depending on the particular patient. (C) 1998 Academic Press.