Korean J Hematol 2002; 37(3):
Published online September 30, 2002
© The Korean Society of Hematology
김진석, 맹호영, 정준원, 이승태, 한지숙, 고윤웅, 민유홍
국민건강보험공단 일산병원 내과,
연세대학교 의과대학 내과학교실
Background : AC133 antigen is a cell surface antigen which is selectively expressed on hematopoietc stem and progenitor cells. It has been reported that AC133 antigen is expressed on the subsets of CD34+ acute leukemia, and occasionally on CD34-acute leukemia. We investigated the clinical and biological characteristics of AC133 antigen-positive acute leukemia.
Method: Thirty-six adult acute leukemia patients were analyzed using a cut-off criterion of 20% or more gated leukemic blasts expressing the AC133 antigen for AC133+ leukemia. The biological characteristics focused on apoptosis were examined using multicolor flow cytometry and Western blot analysis.
Results: AC133 antigen was expressed in 12 cases (33.3%). Eleven of 21 (52.4%) acute myelogenous leukemia (AML) patients and 1 of 15 (6.7%) acute lymphoblastic leukemia patients were positive for AC133 antigen, and the difference was significant. None of the clinical prognostic markers were singificantly different between AC133+ and AC133- AML. Median disease free and overall survival time were not significantly different between AC133+ and AC133-
AML. The expression rate of CD34 was significantly higher in AC133+ AML patients compared to those of AC133- AML (P=0.045). Among the apoptosis-related proteins, the Fas expression on the leukemic blasts was higher in the AC133+ AML(P=0.048), but Fas ligand, Bcl-2, caspase-3 expression rates were not significantly different between AC133+ and AC133 -AML. The apoptosis rate was signigicantly lower in the Ara-C treated AC133 + AML (P=0.049), but the apoptosis rates to other apoptosis-inducing agents (dox-orubicin, TNF-α) were not different between AC133+ and AC133-AML cells. We thought that there were some associations between a trend toward higher caspase-3 expression rates and lower Ara-C induced apoptosis rates in the AC133+ AML.
Conclusion : There was no significant correlation between AC133 antigen expression and various clinical characteristics of acute leukemia, but the AC133 antigen might provide different biological characteristics including apoptosis from other immature cell surface markers. However, to verify the prognostic usefulness of AC133 antigen and the basis of the biological characteristics of AC133 antigen-positive acute leukemia, further study is needed.
Keywords AC133 antigen; Acute leukemia; Apoptosis;
Korean J Hematol 2002; 37(3): 177-190
Published online September 30, 2002
Copyright © The Korean Society of Hematology.
김진석, 맹호영, 정준원, 이승태, 한지숙, 고윤웅, 민유홍
국민건강보험공단 일산병원 내과,
연세대학교 의과대학 내과학교실
Jin Seok Kim, Ho Young Maeng, June Won Cheong, Seung Tae Lee, Jee Sook Hahn, Yun Woong Ko, Yoo Hong Min
Department of Internal Medicine, National Health Insurance Corporation Ilsan Hospital, Goyang
Yonsei University College of Medicine, Seoul, Korea
Background : AC133 antigen is a cell surface antigen which is selectively expressed on hematopoietc stem and progenitor cells. It has been reported that AC133 antigen is expressed on the subsets of CD34+ acute leukemia, and occasionally on CD34-acute leukemia. We investigated the clinical and biological characteristics of AC133 antigen-positive acute leukemia.
Method: Thirty-six adult acute leukemia patients were analyzed using a cut-off criterion of 20% or more gated leukemic blasts expressing the AC133 antigen for AC133+ leukemia. The biological characteristics focused on apoptosis were examined using multicolor flow cytometry and Western blot analysis.
Results: AC133 antigen was expressed in 12 cases (33.3%). Eleven of 21 (52.4%) acute myelogenous leukemia (AML) patients and 1 of 15 (6.7%) acute lymphoblastic leukemia patients were positive for AC133 antigen, and the difference was significant. None of the clinical prognostic markers were singificantly different between AC133+ and AC133- AML. Median disease free and overall survival time were not significantly different between AC133+ and AC133-
AML. The expression rate of CD34 was significantly higher in AC133+ AML patients compared to those of AC133- AML (P=0.045). Among the apoptosis-related proteins, the Fas expression on the leukemic blasts was higher in the AC133+ AML(P=0.048), but Fas ligand, Bcl-2, caspase-3 expression rates were not significantly different between AC133+ and AC133 -AML. The apoptosis rate was signigicantly lower in the Ara-C treated AC133 + AML (P=0.049), but the apoptosis rates to other apoptosis-inducing agents (dox-orubicin, TNF-α) were not different between AC133+ and AC133-AML cells. We thought that there were some associations between a trend toward higher caspase-3 expression rates and lower Ara-C induced apoptosis rates in the AC133+ AML.
Conclusion : There was no significant correlation between AC133 antigen expression and various clinical characteristics of acute leukemia, but the AC133 antigen might provide different biological characteristics including apoptosis from other immature cell surface markers. However, to verify the prognostic usefulness of AC133 antigen and the basis of the biological characteristics of AC133 antigen-positive acute leukemia, further study is needed.
Keywords: AC133 antigen, Acute leukemia, Apoptosis,