Quantitative analysis of Op18 phosphorylation in childhood acute leukemia

• Published in: Leukemia Vol. 11; no. 10; pp. 1690 - 1695
• Main Authors: MELHEM, R, HAILAT, N, KUICK, R, HANASH, S. M
• Format: Journal Article
• Language: English
• Published: London Nature Publishing 01-10-1997; Nature Publishing Group
• Subjects: Acute Disease; Biological and medical sciences; Burkitt Lymphoma - blood; Burkitt Lymphoma - metabolism; Cell cycle; Cell Cycle - physiology; Cell growth; Cell proliferation; Child; Children; Electrophoresis; Gel electrophoresis; Hematologic and hematopoietic diseases; Humans; Leukemia; Leukemia - blood; Leukemia - metabolism; Leukemia, Myeloid, Acute - blood; Leukemia, Myeloid, Acute - metabolism; Leukemia, T-Cell - blood; Leukemia, T-Cell - metabolism; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Leukocyte Count; Lymphocytes - metabolism; Medical sciences; Microtubule Proteins; Oncoprotein 18; Phosphoproteins - metabolism; Phosphorylation; Polyacrylamide; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma - blood; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma - metabolism; Precursor Cell Lymphoblastic Leukemia-Lymphoma - blood; Precursor Cell Lymphoblastic Leukemia-Lymphoma - metabolism; Quantitative analysis; S phase; S Phase - physiology; Stathmin; Human; Cell proliferation; Phosphorylation; Phosphoproteins; Acute; Leukemia; S Phase; Cell cycle; Malignant hemopathy; Molecular biology; Child
• ISSN: 0887-6924; 1476-5551
• DOI: 10.1038/sj.leu.2400792

Oncoprotein 18 (Op18) is a major cystolic phosphoprotein constituent of leukemia cells. There is cumulative evidence that suggests a role for Op18 in integrating signals from diverse pathways involved in cell growth. Op18 phosphorylation is induced with proliferation in a variety of cell types, and is essential for cell cycle progression. In this study we analyzed the level of unphosphorylated Op18 and of its major phosphorylated forms, Op18a and Op18b, in a series of 177 childhood acute leukemias by means of quantitative two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Op18 phosphorylation was significantly correlated with the white blood count at the time of diganosis, and with a high percentage of cells in the S phase. Our findings suggest that strategies to inhibit Op18 expression or phosphorylation may be effective in inhibiting leukemia cell proliferation.