Patients with renal cancer have a larger proportion of high-density blood monocytes with increased lucigenin-enhanced chemiluminescence

The production of oxygen metabolites is probably important in cancer cell killing. The production of the superoxide anion, O2-, can be measured by lucigenin-enhanced chemiluminescence (Cl). Previous studies have shown that whole-blood lucigenin-enhanced Cl is increased in cancer patients and that this increase is related to blood monocyte activity. The present investigation confirmed these findings and showed that whole-blood lucigenin-enhanced Cl was elevated in 17 patients with renal cell adenocarcinoma (P < 0.001). The activity of the monocytes was studied more in detail, whereby monocytes were separated into different populations based upon differences in densities, i.e., high-density and low-density monocytes. The cancer patients had a significantly larger proportion of high-density monocytes (P < 0.05) than controls. The lucigenin-enhanced Cl of purified high-density monocytes in controls was significantly higher than that of low-density monocytes (P < 0.01). The authors conclude that the increase in the lucigenin-enhanced Cl of whole blood observed in cancer patients may partly reflect the increased activity of a larger proportion of high-density monocytes in these patients.