Erythrocyte CD38 as a prognostic marker in cancer

Background: Surface antigen CD38 which is a multifunctional protein with enzymatic and receptorial properties is involved in many processes of cell proliferation and activation. It is widely expressed within the hematopoetic system, and its expression is stimulated by proinflammatory cytokines. CD38-associated enzymatic activities in erythrocytes from cancer patients were investigated in this context. Methods: Erythrocyte NAD glycohydrolase and ADP-ribosyl cyclase activities in normal individuals and cancer patients were compared and correlation of these activities to CEA values and anemia were determined. Changes in CD38-expression were followed by SDS-PAGE and Western blot analysis of erythrocyte membrane proteins. Results: Erythrocyte NAD glycohydrolase and ADP-ribosyl cyclase activities were significantly increased in cancer, in parallel to enhancement of CD38 expression and in correlation with CEA values and anemia. Conclusions: An increased expression of CD38 which may be due to action of proinflammatory cytokines produced in tumor-host reactions appears to account for the elevations in erythrocyte CD38-associated enzyme activities in cancer patients. The changes in these enzyme activities may provide a prognostic outlook in view of their apparently close correlation to tumor progressions.