Scientists at Yonsei University, Medical Research Center target acute myeloid leukemia prognosis

03-22-2007

Scientists discuss in "Protein kinase CK2alpha as an unfavorable prognostic marker and novel therapeutic target in acute myeloid leukemia" new findings in acute myeloid leukemia. According to recent research from Seoul, Korea, "Protein kinase CK2 is implicated in cellular proliferation and transformation. However, the clinical and biological significances of CK2 have not been elucidated in acute myeloid leukemia (AML)."

"We evaluated the biological significances of catalytic subunit of CK2 (CK2alpha) expression in leukemia cell lines and primary leukemic blasts obtained from AML patients. In this study, the expression of CK2alpha was elevated in a substantial proportion of AML. In AML patients with normal karyotype, the disease-free survival and overall survival rates were significantly lower in the CK2alpha-high compared with the CK2alpha-low AML cases (p=0.0252 and p=0.0392, respectively). An induced overexpression of CK2alpha increased the levels of Ser473 phosphorylated (p)-Akt/protein kinase B (PKB), p-PDK1, pFKHR, p-BAD, Bcl-2, Bcl-xL, Mcl-1, and XIAP. Treatment of U937 cell line and primary AML blasts with selective CK2 inhibitor, tetrabromobenzotriazole or apigenin, reduced the levels of these molecules in a dose-dependent manner. CK2alpha small interfering RNA treatment also resulted in a down-regulation of p-Akt/PKB and Bcl-2 in U937 cells. Apigenin-induced cell death was preferentially observed in the CK2alpha-high leukemia cell lines, HL-60 and NB4, which was accompanied by cytoplasmic release of SMAC/DIABLO and proteolytic cleavage of procaspase-9, procaspase-3, procaspase-8, and poly(ADP)ribose polymerase. An induced overexpression of CK2alpha potentially enhanced the sensitivity of U937 cells to the apigenin-induced cell death," wrote J.S. Kim and colleagues, Yonsei University, Medical Research Center.

The researchers concluded: "Apigenin-induced cell death was significantly higher in CK2alpha-high AML compared with CK2alpha-low AML (p <0.0001) or normal bone marrow samples (p <0.0001). These findings strongly suggest protein kinase CK2alpha as an unfavorable prognostic marker and novel therapeutic target in AML."

Kim and colleagues published their study in Clinical Cancer Research (Protein kinase CK2alpha as an unfavorable prognostic marker and novel therapeutic target in acute myeloid leukemia. Clinical Cancer Research, 2007;13(3):1019-28).

For additional information, contact J.S. Kim, Brain Korea 21 Research Team of Nanobiomaterials for the Cell-Based Implants, Dept. of Internal Medicine, Medical Research Center, Yonsei University College of Medicine, Seoul, Korea.

Publisher contact information for the journal Clinical Cancer Research is: American Association Cancer Research, 615 Chestnut St., 17TH Floor, Philadelphia, PA 19106-4404, USA.

This article was prepared by Biotech Business Week editors from staff and other reports. Copyright 2007, Biotech Business Week via NewsRx.com.