Lactobacillus casei extract induces apoptosis in gastric cancer by inhibiting NF-κB and mTOR-mediated signaling

Integr Cancer Ther. 2013 Mar;12(2):165-73. doi: 10.1177/1534735412442380. Epub 2012 Apr 13.

Abstract

Lactobacillus casei extract (LBX) has been reported to prevent gastric cancer, but the underlying mechanism remains unclear. The proliferation and cell death of gastric cancer KATO3 cells were examined after treatment with LBX for various times and at various doses. LBX inhibited the growth of gastric cancer cells and induced apoptosis by inactivating NF-κB promoter activity. Apoptosis induced by LBX, however, is not directly associated with the intrinsic mitochondrial pathway. Immunoblot analysis revealed that LBX decreased the expressions of NF-κB and IκB. The reduced NF-κB levels led to the decreased phosphorylation of mTOR signaling components, such as PI3K, Akt, and (p70)S6 kinase. These results showed for the first time that LBX induced apoptosis in gastric cancer cells by inhibiting NF-κB and mTOR-mediated signaling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / drug effects*
  • Biological Products / pharmacology*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Humans
  • I-kappa B Proteins / metabolism
  • Lactobacillus casei / chemistry*
  • MAP Kinase Signaling System / drug effects
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • NF-kappa B / metabolism*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation / drug effects
  • Promoter Regions, Genetic / drug effects
  • Proto-Oncogene Proteins c-akt / metabolism
  • Ribosomal Protein S6 Kinases, 70-kDa / metabolism
  • Signal Transduction / drug effects*
  • Stomach Neoplasms / drug therapy*
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / pathology
  • TOR Serine-Threonine Kinases / metabolism*

Substances

  • Biological Products
  • I-kappa B Proteins
  • NF-kappa B
  • Phosphatidylinositol 3-Kinases
  • MTOR protein, human
  • TOR Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • Ribosomal Protein S6 Kinases, 70-kDa