Age-Related Co-Expression of BCOR and BCORL1 mRNA in Acute Myeloid Leukemia.

Background: Acute myeloid leukemia (AML) is an aggressive hematological malignancy caused by a variety of genetic abnormalities and epigenetic dysregulation. The incidence of AML is strongly related to age, with the highest incidence rates being in older adults. The loss of function mutations in BCOR and BCORL1 genes have been identified in AML. BCL6 corepressor (BCOR) and BCL6 corepressor like 1 (BCORL1) are important epigenetic regu-lators as a member of Polycomb repressive complex 1 (PRC1.1), involved in histone modification processes.
Methods: We analyzed the BCOR and BCORL1 mRNA expression in 74 adult and 22 pediatric patients with AML by Real-Time quantitative PCR in this study.
Results: Our results indicated that both BCOR and BCORL1 mRNA expressions decrease with age (p = 0.009 and p = 0.008, respectively) and there is a positive correlation between BCOR and BCORL1 mRNA expression (p < 0.001). BCOR and BCORL1 mRNA expressions were not significantly different in both adult and pediatric patients with AML compared to control (p > 0.05).
Conclusions: Our findings indicate that expression of BCOR and BCORL1 mRNA are down-regulated with age. The increase in AML incidence with age suggests that age-associated BCOR and BCORL1 down-regulation might potentially contribute to age-related epigenetic alterations and form a predisposing condition for the development of elderly AML.