PBK/TOPK Is a Novel Mitotic Kinase Which Is Upregulated in Burkitt's Lymphoma and Other Highly Proliferative Malignant Cells

Greenebaum Cancer Center, University of Maryland, 22 South Greene Street, Baltimore, Maryland 21201, USA.
Blood Cells Molecules and Diseases (Impact Factor: 2.33). 09/2001; 27(5):825-9. DOI: 10.1006/bcmd.2001.0452
Source: PubMed

ABSTRACT PBK/TOPK is a recently cloned serine/threonine kinase which is phosphorylated during mitosis. Earlier work indicated that this kinase is upregulated in a Burkitt's lymphoma cell line (GA-10). To determine whether PBK/TOPK is upregulated in other mitotically active neoplastic cell lines and tissues, Northern analysis was performed on a panel of malignant cell lines and on clinical samples from patients with leukemia or lymphoma. While PBK/TOPK mRNA was not detectable in normal peripheral blood cells and was weakly expressed in hyperplastic tonsillar B-cells, significantly higher levels of mRNA were detected in 8 Burkitt's lymphoma cell lines, 10 other neoplastic cell lines, and 2 clinical samples-one derived from a patient with ALL and a second derived from a patient with relapsed myeloma. In addition, Northern analysis of fetal tissues showed upregulated expression of PBK/TOPK in fetal kidney, lung, spleen, brain, and testis. These data suggest that PBK/TOPK expression is increased in highly proliferative malignant cells and during normal fetal development.

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