title: Lupeol enhances radiosensitivity of human hepatocellular carcinoma cell line SMMC-7721 in vitro and in vivo.
abstract: OBJECTIVE
  To investigate the effect of lupeol, a pentacyclictriterpene, on the radiosensitivity of a human hepatocellular carcinoma (HCC) in vitro and in vivo xenografts.
  
  
  METHODS
  SMMC-7721 cells were exposed to γ-radiation with or without lupeol and assayed for proliferation, clonogenic survival, apoptosis and cell cycle distribution. The cells were also analyzed by Western blotting for the expression levels of the proteins involved in apoptosis. Finally radiosensitization by lupeol was assessed in HCC xenograft model.
  
  
  RESULTS
  Lupeol further suppressed the proliferation and colonogenic survival of the SMMC-7721 cells exposed to γ-radiation. It could also induce the accumulation of cells in G2/M phase together with γ-radiation. The data also indicated that lupeol sensitized SMMC-7721 cells exposed to γ-radiation to apoptosis and activated the apoptotic proteins including caspase-9 and PARP. Administration of lupeol with radiation in HCC xenograft model produced a significant tumor growth delay compared with radiation or lupeol alone and was well tolerated.
  
  
  CONCLUSIONS
  Lupeol significantly enhanced the radiosensitivity of SMMC-7721 cells in vitro and in vivo. The mechanisms involved could be cell cycle arrest and induction of apoptosis. Our studies suggest that lupeol has the potential to be developed as an adjuvant for radiotherapy in HCC.
authors.affiliation: Clinical Laboratory, Huai'an Hospital Affiliated of Xuzhou Medical College , Huaian.
authors.forename: Yue
authors.initials: Y
authors.lastname: Jin
authors.forename: Yanguan
authors.initials: Y
authors.lastname: Lyu
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Tang
authors.forename: Yanming
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jianping
authors.initials: J
authors.lastname: Chen
authors.forename: Donghui
authors.initials: D
authors.lastname: Zheng
authors.forename: Yong
authors.initials: Y
authors.lastname: Liang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D059447:Cell Cycle Checkpoints / Q000187:drug effects / Q000528:radiation effects; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D051379:Mice; D053978:Pentacyclic Triterpenes / Q000494:pharmacology*; D011836:Radiation Tolerance / Q000187:drug effects*; D023041:Xenograft Model Antitumor Assays; D000094042:Lupanes
chemical_list: D053978:Pentacyclic Triterpenes; C010480:lupeol; D000094042:Lupanes
keywords: Lupeol; hepatocellular carcinoma cell; radiation; sensitivity