title: The effect of Lactobacillus casei extract on cervical cancer cell lines.
abstract: OBJECTIVE
  Lactobacillus casei (L. casei) has been shown to inhibit the proliferation of several types of cancer in vivo, but its effect on cervical cells has not been reported. We incubated cells of the human cervical cell lines Caski and HeLa with extracts of L. casei and investigated its effects on the growth of the cells and possible synergy with anticancer drugs.
  
  
  METHODS
  Cell-free extracts of L. casei were prepared and purified. Cultures of Caski and HeLa cells adhering to tissue culture plates were treated with L. casei extract. The effects of L. casei extract on the growth of cancer cells and its possible synergy with anti-cancer drugs in cervical cancer cell lines were investigated. The cells were treated with L. casei extract alone, anti-cancer drugs alone [doxorubicin, paclitaxel, 5-fluorouracil (5-FU), and cisplatin], or L. casei extract plus anti-cancer drugs.
  
  
  RESULTS
  L. casei extract had no significant effect on the growth rate of the two cell lines. Anti-cancer drugs alone induced growth inhibition, but there was no synergistic effect of L. casei extract on growth inhibition.
  
  
  CONCLUSIONS
  L. casei extract does not have a potent effect on the viability of cervical cancer cells in vitro. In addition, L. casei extract has no synergistic effect on the inhibition of growth of cancer cells in the presence of anti-cancer drugs.
authors.affiliation: Konkuk University Medical Center, Seoul, South Korea.
authors.forename: Soo-Nyung
authors.initials: SN
authors.lastname: Kim
authors.affiliation: Konkuk University Medical Center, Seoul, South Korea.
authors.forename: Won Moo
authors.initials: WM
authors.lastname: Lee
authors.affiliation: Hanyang University College of Medicine, Seoul, South Korea.
authors.forename: Kyoung Sik
authors.initials: KS
authors.lastname: Park
authors.affiliation: Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Jong Bin
authors.initials: JB
authors.lastname: Kim
authors.affiliation: Biomedical Research Institute, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Dae Jong
authors.initials: DJ
authors.lastname: Han
authors.affiliation: Hanyang University College of Medicine, Seoul, South Korea.
authors.forename: Jaeman
authors.initials: J
authors.lastname: Bae
keywords: Lactobacillus casei; apoptosis; cell viability; chemotherapy