Abstract: ACKGROUND ＆ AIM:Assessed the expression of ZAP_70 in T_NHL, and analyzed the correlation between ZAP_70 and P53,Ki67,to explore the significance of ZAP_70 protein expression in T_NHL. MATERIALS AND METHODS:Evaluated the expression of ZAP_70, P53 and Ki67 in 48 T_NHL by SP immunohistochemistry techniques. The results were analyzed by χ2，t test and Spearman's rank correlation. RESULTS: Expression of ZAP_70 was detected in 58.3％T_cell lymphomas, and the expression of this protein was correlated negatively with tumor grade. Expression of ZAP_70 in high_grade T_NHL was significantly lower than that in low_grade T_NHL(P=0.001).Of 48 T_NHL,expression of P53 was not only correlated positively with tumor grade, but also had a positive relationship with infection of EBV (P<0.05).The expression of ki67 was also increased in high_grade T_NHL. Statistical analysis demonstrated that there was a positive correlation between P53 and Ki67 (P<0.01). CONCLUSION:Absence of ZAP_70 may be diagnostically useful in paraffin sections suggesting T_NHL. Simultaneous measurement of P53 and Ki67 may have great importance in evaluating prognosis and directing therapy after operation in T_NHL.

Key words: T_cell non_Hodgkin lymphoma, ZAP_70, P53, Ki67