Down-Regulation of Telomerase Activity and Activation of Caspase-3 Are Responsible for Tanshinone I-Induced Apoptosis in Monocyte Leukemia Cells in Vitro

International Journal of Molecular Sciences

Xiao-Dan Liu³  Rui-Fang Fan³  Yong Zhang²  Hong-Zhi Yang¹  Zhi-Gang Fang³  Wei-Bing Guan¹  Dong-Jun Lin³  Ruo-Zhi Xiao³  Ren-Wei Huang³  He-Qing Huang⁴  Pei-Qing Liu⁴ 

[1] Department of Traditional Chinese Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510630, China; E-Mails:;Department of Nuclear Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510630, China; E-Mail:;Hematological Department & Institute, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510630, China; E-Mails:;Lab of Pharmacology and Toxicology, School of Pharmaceutical Science of Sun Yat-Sen University, Guangzhou, Guangdong 510080, China; E-Mails:

关键词: Tanshinone I (Tan-I);    telomerase;    survivin;    leukemia;   

DOI  :  10.3390/ijms11062267

来源: mdpi

【 摘 要 】

Tanshinone I (Tan-I) is a diterpene quinone extracted from the traditional herbal medicine Salvia miltiorrhiza Bunge. Recently, Tan-I has been reported to have anti-tumor effects. In this study, we investigated the growth inhibition and apoptosis inducing effects of Tan-I on three kinds of monocytic leukemia cells (U937, THP-1 and SHI 1). Cell viability was measured by MTT assay. Cell apoptosis was assessed by flow cytometry (FCM) and AnnexinV/PI staining. Reverse transcriptase polymerase chain reaction (RT-PCR) and PCR–enzyme-linked immunosorbent assay (ELISA) were used to detect human telomerase reverse transcriptase (hTERT) expression and telomerase activity before and after apoptosis. The activity of caspase-3 was determined by Caspase colorimetric assay kit and Western blot analysis. Expression of the anti-apoptotic gene Survivin was assayed by Western blot and Real-time RT-PCR using the ABI PRISM 7500 Sequence Detection System. The results revealed that Tan-I could inhibit the growth of these three kinds of leukemia cells and cause apoptosis in a time- and dose-dependent manner. After treatment by Tan-I for 48 h, Western blotting showed cleavage of the caspase-3 zymogen protein with the appearance of its 17-kD subunit, and a 89-kD cleavage product of poly (ADP-ribose) polymerase (PARP), a known substrate of caspase-3, was also found clearly. The expression of hTERT mRNA as well as activity of telomerase were decreased concurrently in a dose-dependent manner. Moreover, Real-time RT-PCR and Western blot revealed a significant down-regulation of Survivin. We therefore conclude that the induction of apoptosis by Tan-I in monocytic leukemia U937 THP-1 and SHI 1 cells is highly correlated with activation of caspase-3 and decreasing of hTERT mRNA expression and telomerase activity as well as down-regulation of Survivin expression. To our knowledge, this is the first report about the effects of Tan-I on monocytic leukemia cells.

【 授权许可】

CC BY   
© 2010 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.