title: The extract of Hibiscus syriacus inducing apoptosis by activating p53 and AIF in human lung cancer cells.
abstract: Natural products including plants, microorganisms and marine life provide rich resources for anticancer drug discovery. The root bark of Hibiscus syriacus has been used as an antipyretic, anthelmintic and antifungal agent in Asia. The antiproliferative effects of H. syriacus on human lung cancer cells were evaluated with bio-assays. The apoptotic activity was detected by Hoechst 33342 DNA staining and annexin V staining. The expression of caspases, p53, apoptosis induced factor (AIF), Bcl-2 and Bax were evaluated with Western blotting. The in vivo anticancer activity was evaluated using A549-xenograft model. The acetone extract of H. syriacus (HS-AE) exhibited a better cytotoxic effect on lung cancer cells than its methanol extract (HS-ME) or water extract (HS-WE). The IC(50) values of HS-AE on A549 (adenocarcinoma), H209 (squamous cell carcinoma) or H661 (large cell carcinoma) lung cancer cells ranged from 14 to 22 microg/ml after 48 hours of treatment. After 48 hours of exposure, HS-AE (15 microg/ml) induced A549 cell apoptosis to 48 +/- 3.6% of the control. Using Western blotting, HS-AE appears to suppress the expression of p53 and AIF. The results of the in vivo study showed that HS-AE suppresses growth in A549 subcutaneous xenograft tumors. These results indicate that HS-AE exerts significant and dose-dependent antiproliferative effects on cancer cells in vitro and in vivo, which prompts us to further evaluate and elucidate the bioactive component(s) of H. syriacus.
authors.affiliation: Laboratory of Herbal Medicine and Molecular Oncology in Division of Thoracic Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan. ndmc0928@yahoo.com.tw
authors.forename: Yeung-Leung
authors.initials: YL
authors.lastname: Cheng
authors.forename: Shih-Chun
authors.initials: SC
authors.lastname: Lee
authors.forename: Horng-Jyh
authors.initials: HJ
authors.lastname: Harn
authors.forename: Hsin-Chieh
authors.initials: HC
authors.lastname: Huang
authors.forename: Wen-Liang
authors.initials: WL
authors.lastname: Chang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D051033:Apoptosis Inducing Factor / Q000187:drug effects / Q000235:genetics*; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D005260:Female; D031584:Hibiscus; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000502:physiology*
chemical_list: C494829:AIFM1 protein, human; D051033:Apoptosis Inducing Factor; D010936:Plant Extracts; D016159:Tumor Suppressor Protein p53