title: Natural static magnetic field-induced apoptosis in liver cancer cell.
abstract: OBJECTIVE
  To observe the apoptotic effects of NSMF on human hepatoma cells and to investigate the mechanisms.
  
  
  METHODS
  Human hepatoma cell line Bel-7402 and Hep G-2 were treated by 0.2 T rotary NSMF (30 min/d) with 250 Hz, 400 Hz and 500 Hz for 3 d and 6 d, respectively. Apoptosis was analyzed with flow cytometry. Cell proliferation was measured with XTT assay. Expression of Bcl-2, caspase3/8/9 was analyzed with ELISA.
  
  
  RESULTS
  After 6 d treatment, significant apoptosis was induced by 400 Hz in Bel-7402 cells. Slight cell apoptosis was observed at 250 Hz, while Hep G-2 cells exhibited slight apoptosis at 250 Hz and 400 Hz. After 3 d treatment, no apoptosis exhibited in both cell types. Compared with control group, expression of Bcl-2 and Caspase 8 in treated Bel-7402 cells were significantly reduced (p < 0.01), while Caspase 3 and Caspase 9 were significantly upregulated (p < 0.01).
  
  
  CONCLUSIONS
  NSMF upregulates caspase 9 and downregulates Bel-2 expression, which results in higher level of active caspase 3 to trigger apoptosis in cells. Different cell types require different NSMF factors like rotary frequency and treatment time to induce apoptosis.
authors.affiliation: Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University , Hangzhou , China .
authors.forename: Jianhua
authors.initials: J
authors.lastname: Li
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Ma
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.forename: Yanping
authors.initials: Y
authors.lastname: Cao
authors.forename: Yifan
authors.initials: Y
authors.lastname: Zhu
mesh_terms: D017209:Apoptosis; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D045744:Cell Line, Tumor; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D060526:Magnetic Fields