Liver Cancer
Copyright ©The Author(s) 2004. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 15, 2004; 10(18): 2632-2636
Published online Sep 15, 2004. doi: 10.3748/wjg.v10.i18.2632
Mitotic cell death in BEL-7402 cells induced by enediyne antibiotic lidamycin is associated with centrosome overduplication
Yue-Xin Liang, Wei Zhang, Dian-Dong Li, Hui-Tu Liu, Ping Gao, Yi-Na Sun, Rong-Guang Shao
Yue-Xin Liang, Dian-Dong Li, Rong-Guang Shao, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
Wei Zhang, Hui-Tu Liu, Ping Gao, Yi-Na Sun, Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Science, Beijing Normal University, Beijing 100875, China
Author contributions: All authors contributed equally to the work.
Supported by Grants from the Major State Basic Research Development Program Foundation of China, No. G2000057010 and G1999053901 and Grants from the National Natural Science Foundation of China, No. 30271438 and 30300424 and Grant from the Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, Beijing Normal University. No. CPR2001-004
Correspondence to: Professor Dian-Dong Li, Institute of Medicinal Biotechnology, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100050, China. ddli@public3.bta.net.cn
Telephone: +86-10-63165289 Fax: +86-10-63017302
Received: February 14, 2004
Revised: February 18, 2004
Accepted: February 21, 2004
Published online: September 15, 2004
Abstract

AIM: Mitotic cell death has been focused on in tumor therapy. However, the precise mechanisms underlying it remain unclear. We have reported previously that enediyne antibiotic lidamycin induces mitotic cell death at low concentrations in human epithelial tumor cells. The aim of this study was to investigate the possible link between centrosome dynamics and lidamycin-induced mitotic cell death in human hepatoma BEL-7402 cells.

METHODS: Growth curve was established by MTT assay. Cell multinucleation was detected by staining with Hoechst 33342. Flow cytometry was used to analyze cell cycle. Aberrant centrosomes were detected by indirect immunofluorescence. Western blot and senescence-associated β-galactosidase (SA-β-gal) staining were used to analyze protein expression and senescence-like phenotype, respectively.

RESULTS: Exposure of BEL-7402 cells to a low concentration of lidamycin resulted in an increase in cells containing multiple centrosomes in association with the appearance of mitotic cell death and activation of SA-β-gal in some cells, accompanied by the changes of protein expression for the regulation of proliferation and apoptosis. The mitochondrial signaling pathway, one of the major apoptotic pathways, was not activated during mitotic cell death. The aberrant centrosomes contributed to the multipolar mitotic spindles formation, which might lead to an unbalanced division of chromosomes and mitotic cell death characterized by the manifestation of multi- or micronucleated giant cells. Cell cycle analysis revealed that the lidamycin treatment provoked the retardation at G2/M phase, which might be involved in the centrosome overduplication.

CONCLUSION: Mitotic cell death and senescence can be induced by treatment of BEL-7402 cells with a low concentration of lidamycin. Centrosome dysregulation may play a critical role in mitotic failure and ultimate cell death following exposure to intermediate dose of lidamycin.

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