Comparison between expression levels and prognostic influence of minichromosome maintenance 8 gene in pediatric and adult patients with acute myeloid leukemia

Background
Minichromosome maintenance 8 (MCM8) gene is essential for DNA replication and repair as well as genome stability. However, uncontrolled expression of MCM8 may drive cancer.


Objectives
To study the expression levels of MCM8 gene mRNA and its effect on treatment outcomes in a cohort of pediatric and adult Egyptian patients who were newly diagnosed with acute myeloid leukemia (AML).


Patients and methods
The study included 70 adults with AML, 40 children with AML, and 25 age-matched and sex-matched healthy individuals, who served as controls for each group. MCM8 expression levels were measured in the peripheral blood samples by real-time reverse transcriptase PCR.


Results

MCM8 expression was significantly high in adult and pediatric AML cases compared with their corresponding control groups (
P
<0.001), with significant value in differentiating patients with AML from healthy individuals. In the pediatric group, high MCM8 expression levels were positively correlated with blast count in peripheral blood (
r
=0.460,
P
=0.003) and bone marrow (
r
=0.344,
P
=0.03) samples. MCM8 overexpression was associated with a higher complete remission rate on day 28 of induction therapy (
P
=0.04). Low MCM8 expression levels were associated with unsatisfactory overall survival (OS) in pediatric AML cases, whereas MCM8 expression levels did not affect OS in adult AML cases. Furthermore, Cox hazard regression analysis identified MCM8 as a significant predictor of OS in pediatric and not in adult AML cases.



Conclusion
MCM8 could serve as a potential diagnostic biomarker in pediatric and adult AML cases, and it is an independent prognostic marker in pediatric AML.