Apoptosis induction of ZBB-006, a novel synthetic diterpenoid, in the human hepatocellular carcinoma cell line HepG2 in vitro and in vivo.
Diterpenes, present in many medicinal plants, have been the focus of continuous studies for the development of new anticancer agents. ZBB-006 is a new synthetic diterpenoid derivative which exhibited significant anti-proliferation activity against various cancer cell lines in our previous study. Here, we investigated the antitumor effect of ZBB-006 and its potential mechanisms in the human hepatocellular carcinoma cell line HepG2, both in vitro and in vivo. We found that oral administration of ZBB-006 effectively suppressed the growth of HepG2 xenograft tumor in nude mice without body weight decline as compared with the control group. Meanwhile, the growth inhibitory effect of ZBB-006 on HepG2 cells was observed with MTT assay. Apoptosis induced by ZBB-006 in HepG2 cells was evidenced by DAPI staining and Annexin V/PI double staining assay. ZBB-006 also dissipated the mitochondrial membrane potential (ΔΨm) apparently as revealed by JC-1 staining. Furthermore, the cleavage of PARP, activation of caspase-3 and caspase-9 but not caspase-8 was demonstrated by western blot assay both in vitro and in vivo. Additionally, the proapoptotic protein Bax was markedly elevated, while the antiapoptotic protein Bcl-2 was downregulated. Collectively, our data indicated that ZBB-006 exerted a strong antitumor effect on HepG2 cells by initiating the mitochondrial-dependent apoptosis, and it has potential to be explored as a new promising therapeutic agent against human hepatoma.
Fan
Qian-Qian
QQ
College of Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China.
Wang
Qiu-Juan
QJ
Zeng
Bu-Bing
BB
Ji
Wen-Hao
WH
Ji
Hui
H
Wu
Yu-Lin
YL
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001562:Benzimidazoles; D002232:Carbocyanines; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D048708:Cell Growth Processes / Q000187:drug effects; D004224:Diterpenes / Q000494:pharmacology*; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D023041:Xenograft Model Antitumor Assays
D001562:Benzimidazoles; D002232:Carbocyanines; D004224:Diterpenes; C557212:ZBB-006; C068624:5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine