Analysis of Antioxidant Enzymes Combined with the Detection of MCL-1 and Bax Expressions in Acute Childhood Leukemias

To investigate the involvement of apoptosis regulating proteins in acute leukemias, immunocytochemical examination of Mcl-1 and Bax proteins expression was investigated in two groups of patients, one with acute lymphoblastic leukemia (ALL) and the other with acute myeloid leukemia (AML). Therefore, the free radicals utilizing enzymes including superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and catalase (CAT), in addition to malonaldhyde (MDH), nitric oxide (NO), and glutathione content (GSH) were investigated. The obtained results showed a significant difference of SOD, GSH-PX, CAT, MDH, NO, and GSH levels in the leukemia patients (AML, ALL) compared to control group (p<0.001). On the other hand, there was a significant difference of SOD, GSH-PX, MDH, NO, and GSH levels in the AML group compared to ALL patients (p<0.001). In AML patients, a significant positive correlation was existed between SOD and GSH-PX (p<0.001) and a negative correlation was existed between catalase and MDH (p<0.019). Mcl-1 expression was found positive 32.3% of ALL patients versus 55% of AML patients. Concerning Bax reactivity, only 23% were positive in ALL patients versus 35.5% of AML patients. In ALL patients, a positive correlation was found between Mcl-1 and Bax expressions (p=0.011). In conclusion, these results collectively reflect remarkable differences between AML and ALL suggesting different mechanisms underlying their formation and their progression. Mcl-1 and Bax expressions relating to the programmed cell death (PCD) or apoptosis in addition to the anti-oxidant status are deregulated mechanisms that contribute in the pathobiology of ALL differently from AML.