Study of Hydroxyurea Induced Caspase Activities in Chronic Myelogenous Leukemic Cell Line, K562 cells.
- Author:
Young Jin LEE
1
;
Rae Kil PARK
;
Hong Seob SO
;
Ji Sun PARK
;
Ji Hyun CHO
;
Sam Im CHOI
Author Information
1. Department of Clinical Pathology, Wonkwang University, School of Medicine, Iksan.
- Publication Type:Original Article
- Keywords:
Hydroxyurea;
K562 cells;
Apoptosis;
Caspase;
Phosphatidylserine;
DNA fragmentation
- MeSH:
Annexin A5;
Apoptosis;
Cell Line*;
Culture Media;
DNA Fragmentation;
Electrophoresis, Agar Gel;
Humans;
Hydroxyurea*;
K562 Cells*;
L-Lactate Dehydrogenase;
Leukemia, Myelogenous, Chronic, BCR-ABL Positive;
Leukocytosis;
Myeloproliferative Disorders;
Peptide Hydrolases
- From:Korean Journal of Clinical Pathology
2000;20(5):435-441
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Chronic myelogenous leukemia is a chronic myeloproliferative disorder characterized by leukocytosis with myeloid elements at all stages of differentiation, t(9;22)(q34;q11) and bcr/abl rearrangement. We studied hydroxyurea induced apoptotic changes such as externalization of phosphatidylserine, caspase activities on human chronic myelogenous leukemic cell line, K562 cells. METHODS: K562 cells were grown in RPMI 1640 supplemented with 10% fetal bovine serum and treated hydroxyurea. Viability was examined by MTT assay. Apoptosis were examined by annexin V stain, caspase (such as caspase-, caspase-, caspase-, caspase-, and caspase-) activities, and DNA fragmentation. RESULTS: The viability of K562 cells were markedly decreased in a dose dependent manner of hydroxyurea. Phosphatidylserine externalization was detected by annexin V stain after 3 hours in hydroxyurea treated K562 cells and the value of lactate dehydrogenase was not significantly changed in their culture media. The upstream effector of caspase- was slightly increased and had influenced on caspase-. And downstream acting caspase protease of caspase- was markedly increased in a time dependent manner at hydroxyurea treated K562 cells. In addition, however the activities of caspase- and caspase- were not increased. We also found DNA fragmentation at hydroxyurea treated K562 cells between 48 hours and 72 hours on agarose gel electrophoresis. CONCLUSIONS: Hydroxyurea induces apoptotic change in K562 cells via externalization of phosphatidylserine, activations of caspase-, caspase-, caspase- proteases, and DNA fragmentation.
