Bufalin induces apoptosis and influences the expression of apoptosis-related genes in human leukemia cells

• Published in: Leukemia research Vol. 19; no. 8; pp. 549 - 556
• Main Authors: Masuda, Yutaka, Kawazoe, Nobuko, Nakajo, Shigeo, Yoshida, Takemi, Kuroiwa, Yukio, Nakaya, Kazuyasu
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.1995; Elsevier Science
• Subjects: Animals; Antineoplastic agents; Aphidicolin - pharmacology; apoptosis; Apoptosis - drug effects; bcl-2; Biological and medical sciences; Bufalin; Bufanolides - pharmacology; c-myc; Cycloheximide - pharmacology; DNA Damage; DNA fragmentation; Gene Expression - drug effects; General aspects; Genes, myc; Humans; leukemia; Medical sciences; Mice; Pharmacology. Drug treatments; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins c-bcl-2; Proto-Oncogene Proteins c-myb; RNA, Messenger - genetics; RNA, Neoplasm - genetics; Tumor Cells, Cultured - drug effects; Zinc - pharmacology; Asia; China; leukemia; apoptosis; bcl-2; c-myc; Bufalin; DNA fragmentation; Antineoplastic agent; Human; Leukemia; Malignant hemopathy; Bufadienolide; Gene expression; In vitro; HL60 cell line; Folk medicine; Cell death; C-Onc gene; Established cell line; Protooncogene; Apoptosis
• ISSN: 0145-2126; 1873-5835
• DOI: 10.1016/0145-2126(95)00031-I

A low concentration of bufalin, a component of bufadienoides in the traditional Chinese medicine chan'su, was shown previously to induce differentiation of a broad range of human leukemia cell lines. In the present study, we found that bufalin at concentrations of 10 −7 M and higher induced apoptosis in human leukemia cells, such as HL60, ML1, but not in mouse leukemia M1 cells. A mere 15 min pretreatment of HL60 cells with 10 −6 M bufalin, followed by incubation for 15 h without bufalin, caused fragmentation of DNA and a decrease in cell viability, indicating that the signal for induction of apoptosis is triggered rapidly upon treatment with bufalin. Bufalin-induced apoptosis in HL60 cells was inhibited by ZnCl 2, an inhibitor of endonuclease, but not by cycloheximide, an inhibitor of protein synthesis. Northern blot analysis revealed that the levels of expression of the c-myc and bcl-2 genes in HL60 cells decreased with time after treatment with bufalin. These results suggest that bufalin induces apoptosis specifically in human leukemia cells by altering the expression of these genes involved in apoptosis.