Expression Of Bcl-2 And Bax Gene In Acute Leukemia And Its Clinical Significance

To investigate the clinical significance and the expression of bcl-2 and bax gene in acute leukemia(AL). Methods: 63 cases of initial diagnosed AL were examined and 33/63 cases were followed up by in situ hybridization with streptavidin-gold(ISH-SAG). Results:(1) The results showed that almost all subtypes of initial diagnosed AL had bcl-2 and bax expression. ANLL had a higher positive expression rate than that in ALL, but the difference was not significant (p>0.05). (2) In the 42/63 cases accepted standard chemotherapy, high expression of bcl-2 was associated with a low complete remission(CR) rate(75.0% in case with less than 20% positive cell. 33.3% in case with more than 20% positive cell, P<0.05). CR rate was 50.0% in bax positive cases and 66.7% in negative cases. The difference did not significantly differ (P>0.05). (3) In the follow-up 33 cases, the positive rate of bcl-2 and bax in relapse or refractory group (92.9%, 35.7%) were statistically different from those in CR group (57.9%, 89.5%) (P<0.05). (4) Bcl-2/Bax ratio >1.0 was related to a low CR rate. The complete remission rate between bcl-2/bax ratio >1.0 and ratio ≤1.0 (34.8%,89.5%)were significant different after standard chemotherapy in initial diagnosed AL (P<0.001). (5) the sensitivity,specificity,accuracy of bcl-2/bax ratio were 88.2%,68.0%,76.2% respectively. Conclusion: Expression of bcl-2 and especially bcl-2/bax ratio in initial diagnosed AL were significantly correlated with the clinical prognosis and drug resistant. The determination of bcl-2 and bax expression in AL could provide useful information for predicting prognosis,designing chemotherapeutic regimen and predicting the treatment effect. It would be significantly applied in clinical practice.