title: Cytotoxic genes from traditional Chinese medicine inhibit tumor growth both in vitro and in vivo.
abstract: OBJECTIVE
  Little effort has been made to study the protein-encoding genes isolated from traditional Chinese medicine (TCM) drugs, and the delivery of these genes into malignant cells through recombinant adeno-associated virus (rAAV) vectors has not been attempted.
  
  
  METHODS
  We synthesized the cDNAs of five known cytotoxic proteins isolated from TCM drugs and the FLAG epitope-tagged cDNAs were subcloned into a rAAV plasmid vector. The protein expression was confirmed by Western blot assay. Various cancer cell lines were transfected with the above plasmids and cell growth was monitored both in vitro and in vivo. The best cytotoxic gene was further packaged into rAAV vectors, under the control of a liver cancer-specific promoter. The liver tumor growth was then monitored following intratumor administration of the rAAV vectors.
  
  
  RESULTS
  The expression plasmids, encoding individual potential cytotoxic genes tagged with FLAG epitope, were successfully generated and sequenced. Among these genes, trichosanthin (TCS) gene yielded the most promising results for the inhibition of cancer cell growth in vitro. The over-expressed TCS functioned as a type I ribosome-inactivating protein, followed by inducing apoptosis that is associated with the Bcl-PARP signaling pathway. Furthermore, intratumor injection of rAAV vectors containing the TCS gene significantly inhibited the growth of human hepatocellular carcinoma tumors in a murine xenograft model.
  
  
  CONCLUSIONS
  Our studies suggest that the use of TCM cytotoxic genes is a useful therapeutic strategy for treating human cancers in general, and liver tumors in particular.
authors.affiliation: Changhai Hospital of Traditional Chinese Medicine, Second Military Medical University, Shanghai 200433, China.
authors.forename: Yuan-hui
authors.initials: YH
authors.lastname: Zhang
authors.affiliation: Changhai Hospital of Traditional Chinese Medicine, Second Military Medical University, Shanghai 200433, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32611, USA.
authors.forename: Ali Hussein
authors.initials: AH
authors.lastname: Yusufali
authors.affiliation: Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32611, USA.
authors.forename: Frederick
authors.initials: F
authors.lastname: Ashby
authors.affiliation: Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32611, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Changhai Hospital of Traditional Chinese Medicine, Second Military Medical University, Shanghai 200433, China.
authors.forename: Zi-fei
authors.initials: ZF
authors.lastname: Yin
authors.affiliation: Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32611, USA.
authors.forename: George V
authors.initials: GV
authors.lastname: Aslanidi
authors.affiliation: Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32611, USA.
authors.forename: Arun
authors.initials: A
authors.lastname: Srivastava
authors.affiliation: Changhai Hospital of Traditional Chinese Medicine, Second Military Medical University, Shanghai 200433, China; E-mail: lingchangquan@hotmail.com.
authors.forename: Chang-quan
authors.initials: CQ
authors.lastname: Ling
authors.affiliation: Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32611, USA; E-mail: lingchen@peds.ufl.edu.
authors.forename: Chen
authors.initials: C
authors.lastname: Ling
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000502:physiology; D045744:Cell Line, Tumor; D018076:DNA, Complementary; D000229:Dependovirus; D005822:Genetic Vectors; D006801:Humans; D008113:Liver Neoplasms / Q000503:physiopathology; D008516:Medicine, Chinese Traditional / Q000379:methods*; D051379:Mice; D009369:Neoplasms / Q000503:physiopathology*; D015978:Trichosanthin / Q000235:genetics* / Q000494:pharmacology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D018076:DNA, Complementary; D015978:Trichosanthin