Background: Despite the advances in the cure rate for acute leukemia, approximately
25% of affected patients suffer from relapses. Expression of genes for the multiple drug
resistance (MDR-1) and breast cancer related protein (BCRP) may confer the
phenotype of resistance to the treatment of acute leukemia. Objective: To analyze the
expression of the MDR-1 and BCRP genes in new cases of acute leukemia via the
real time polymerase chain reaction (RT-PCR) and to determine the correlation
between their expression and overall survival. Patients and methods: Total number of
patients diagnosed as AML (n = 15), ALL (n = 35) and 20 blood donors as a control
group included in this study. The expression of messenger RNA for the MDR-1and
BCRP genes by RT-PCR were assessed. Myeloid surface markers as (CD34, CD33,
CD13 and CD14) and lymphoid surface markers as (CD3,CD5, CD2, CD4 ,CD8 and
CD19)were analyzed by flow cytometry (FACS can, Becton Dickinson, Mountain View,
CA, USA). Results: The studied groups with MDR gene, BCRP gene show highly
significant difference compared to the control (P<0.000). The relation between MDR &
BCRP in both AML and ALL groups shows no significant difference. There was a
significant difference between BCRP expression in AML, ALL groups (P<0.01). No
significant difference as regards overall survival between MDR +ve cases and MDR
negative cases in AML and ALL. In contrast Overall survival in BCRP +ve cases and
BCRP negative cases shows a significant difference between AML and ALL groups
(P<0.01). No significant difference was detected between O.S in AML (MDR +ve ,
CD34 +ve) and AML (MDR +ve, CD34 negative). In contrast, O.S between AML
(BCRP +ve ,CD34 +ve)and AML (BCRP +ve ,CD34 negative) shows a significant
difference (P<0.01). The difference between O.S in ALL (MDR +ve, CD34 +ve) and
ALL (MDR +ve, CD34 negative) was not significant. In contrast a significant difference
was detected between O.S in ALL (BCRP +ve, CD34 +ve) and ALL (BCRR +ve, CD34
negative) (P<0.01). Overall survinal in AML group with BCRP +ve (CD13 +ve) shows a
significant difference (P<0.01). In ALL group the association between (MDR +ve and
CD19 +ve) or (BCRP +ve and CD19 +ve) cannot significantly affect the survival.
Conclusion: We concluded that the evaluation of the expression of genes for
resistance to antineoplastic drugs in acute leukemia upon diagnosis, and particularly
the expression of the BCRP gene, may be of clinical relevance.