Human monocyte glucose metabolism in lymphoma.

Glycolysis (GU), hexose monophosphate shunt (HMPS) activity, and Krebs cycle activity were determined in monocytes from 32 normal subjects and 22 untreated patients with lymphoma. All of these parameters of glucose metabolism were significantly elevated in the lymphoma patients as a group when compared to normal subjects, suggesting monocyte activation by lymphoma. When the results were evaluated on the basis of sex and age, significant enhancement of glucose metabolism by lymphoma was evident in the 13 male patients compared to 18 normal men but not in monocytes from nine women with lymphoma compared to 14 normal subjects. Male patients over and under 40 years of age had significantly enhanced HMPS activity compared to normal subjects (p less than 0.05 and p less than 0.01, respectively), and GU was significantly increased in patients over 40 years (p less than 0.01). In contrast, no significant differences were noted in any of the values of women with lymphoma compared to normal subjects matched according to menstrual status. This discrepancy is apparently due to the high values for HMPS noted in healthy women, especially menstruating women. Although lymphoma may activate monocyte glucose metabolism, this effect can be masked by the normally high values seen in healthy women. The sex of the subject must be considered in evaluating human monocyte function and metabolism.