EFFECT OF ARGINASE ON SPLENIC KILLER-CELL ACTIVITY IN PATIENTS WITH GASTRIC-CANCER

Arginase has been detected in high levels in gastric cancer tissues. T he effect of arginase on the activities of splenic natural killer (NK) cell, phytohemagglutinin activated killer (PAK) cell, and interleukin -2 activated killer (LAK) cell in patients with gastric cancer (N = 12 ) was evaluated in vitro. These activities inpatients (N = 10) with tr auma and benign lesions were used as control. The splenic NK and PAK c ell activities in patients with gastric cancer were significantly lowe r than in the controls (P < 0.05), whereas LAK cell activity did not h ave significant difference. Arginase inhibited all splenic killer cell activities to a similar degree between patients with gastric cancer a nd the controls. The inhibition was dose-related. These data suggest t hat arginase may play a positive role in the spread of gastric cancer cells. However, LAK may be a potential approach of immunodepleted ther apy in the future.