Objective: To evaluate the expression of CD133 and its clinical significance in acute leukemia (AL) patients.
Methods: The expression of CD133 and CD133 mRNA in leukemic blasts from 76 AL patients were detected by three-color flow-cytometry and hemi-quantitative RT-PCR respectively.
Results: (1) CD133 mRNA expression was highly correlated with CD133 expression in both of normal donors and AL patients groups. The expression of CD133 in AL patients was significantly higher than that in control group (P < 0.01). (2) The positive rates of CD133 and CD133 mRNA in AL group were 42.1% (32/76) and 46.1% (35/76) respectively. There was no significant difference in CD133 expression between AML-M(3) and normal control, AML and ALL, as well as T-ALL and B-ALL. The expression of CD133 in AML-M(4) were significantly higher than those in other AML subtypes (81.8% vs 43.7% and 81.8% vs 46.9% at CD133 and CD133 mRNA level, respectively, P < 0.01). (3) The expression of CD133 in AML was significantly correlated with the expression of CD34 and HLA-DR (P < 0.001). (4) The expression of CD133 had no relationship with the clinical prognostic factors such as cytogenetic or molecular aberrations, WBC counts, LDH, mdr1 expression and age. (5) There was a trend toward lower CR rate in CD133(+) cases, but only CD34/CD133(+) double positive cases had significant lower CR rate than that of negative ones (44.4% vs 71.4%, P < 0.05).
Conclusions: AL had significantly higher CD133 expression compared to normal control. The detection of CD133 expression might help to identify AL type and predict therapeutic outcomes. Co-expression of CD133/CD34 might convey adverse prognosis of AL.