Overexpression of cancerous inhibitor ofPP2A (CIP2A) in acute myeloid leukemia.

BACKGROUND

Acute myeloid leukemia (AML) is a heterogeneous hematologic malignancy. Protein phosphatase 2A Protein phosphatase 2A (PP2A) is a major serine/threonine phosphatase and tumor suppressor that negatively regulates numerous signal transduction pathways. Cancerous inhibitor of PP2A (CIP2A) is an endogenous inhibitor of PP2A. CIP2A overexpression was shown to be a recurrent event in cytogenetic normal AML patients. The aim of the study is to evaluate the prognostic significance of CIP2A overexpression in patients with AML.

RESEARCH DESIGN AND

METHODS

The study included 174 newly diagnosed cytogenetic normal AML patients. Detection of CIP2A expression was performed using quantitative real-time PCR.

RESULTS

CIP2A was overexpressed in 125/174 (71.8%) of patients. Correlation of CIP2A overexpression with other prognostic factors showed significant association with CD34 expression (p = 0.04). CIP2A overexpression was significantly associated with a lower rate of (complete remission) CR (p = 0.019) and shorter disease free survival (DFS) and overall survival (OS) (p < 0.001 and <0.001, respectively). In multivariate analysis, CIP2A overexpression was an independent adverse prognostic factor that negatively affected DFS and OS (p < 0.001, HR:2.8,95%CI:1.7-4.7 and p = 0.002, HR:1.8; 95%CI:1.2-2.65, respectively).

CONCLUSION

CIP2A overexpression is a useful prognostic marker in AML.