Background: Acute lymphoblastic leukemia (ALL) is the most common type of leukemia in children.Several environmental and genetic factors are known to be involved in its development and progression. The angiopoietin-Tie system is one of the most critical factors in angiogenesis, and its possible role in solid tumors and leukemia has been previously investigated. In this study, we examined the expression of these genes in ALL patients (early pre-B-ALL and pre-B-ALL) and compared them with normal samples. Methods: Bone marrow samples were collected from 40 patients (aged 0‒19 yr) newly diagnosed with early pre-B-ALL or pre-B-ALL using molecular and flow cytometric tests and from 15 control individuals. For molecular tests, RNA extraction and cDNA synthesis were performed, and Ang1, Ang2, Ang4, Tie1, and Tie2 gene expression was examined by real-time polymerase chain reaction. Results: Ang2, Tie1, and Tie2 gene expression were significantly increased in patients with ALL, whereas Ang1 gene expression was decreased. The Ang4 gene did not show significant expression changes between the two groups. Conclusion Changes in the expression of the Ang-Tie system indicate a possible role of angiogenesis in ALL prognosis. Moreover, such changes can be considered as potential diagnostic biomarkers or therapeutic targets.

Background: Acute lymphoblastic leukemia (ALL) is the most common type of leukemia in children.Several environmental and genetic factors are known to be involved in its development and progression. The angiopoietin-Tie system is one of the most critical factors in angiogenesis, and its possible role in solid tumors and leukemia has been previously investigated. In this study, we examined the expression of these genes in ALL patients (early pre-B-ALL and pre-B-ALL) and compared them with normal samples. Methods: Bone marrow samples were collected from 40 patients (aged 0‒19 yr) newly diagnosed with early pre-B-ALL or pre-B-ALL using molecular and flow cytometric tests and from 15 control individuals. For molecular tests, RNA extraction and cDNA synthesis were performed, and Ang1, Ang2, Ang4, Tie1, and Tie2 gene expression was examined by real-time polymerase chain reaction. Results: Ang2, Tie1, and Tie2 gene expression were significantly increased in patients with ALL, whereas Ang1 gene expression was decreased. The Ang4 gene did not show significant expression changes between the two groups. Conclusion Changes in the expression of the Ang-Tie system indicate a possible role of angiogenesis in ALL prognosis. Moreover, such changes can be considered as potential diagnostic biomarkers or therapeutic targets.