[Effect of lipoteichoic acid of Bifidobacterium on survivin and its regulatory genes].
OBJECTIVE
The aim of this study is designed to explore the anti-tumor effect of lipoteichoic acid (LTA) of Bifidobacterium on the expression of survivin in colon cancer LoVo cells and its possible regulatory mechanism.


METHODS
The changes of survivin mRNA and protein in LoVo cells treated with LTA of Bifidobacterium were detected by RT-PCR and Western blot. Meanwhile, the expressions of pAKT (the key protein kinase in P13K/AKT signal transduction pathway), p53 and PTEN were measured by Western blot.


RESULTS
There were overexpressions of survivin mRNA and protein in LoVo cells. After treated with different dose of LTA of Bifidobacterium, the expressions of survivin mRNA and protein were markedly decreased in a dose-dependent manner (P < 0.01). Besides, the activity of pAKT was decreased significantly (P < 0.01) and the expression of p53 and PTEN was increased (P < 0.01).


CONCLUSIONS
LTA of Bifidobacterium can down-regulate the expression of survivin in LoVo cells through inhibiting the activity of PI3K/AKT signal transduction pathway and up-regulate the expression of p53. Accordingly, the activity of caspases is increased, and apoptosis of LoVo cells occurs ultimately.
Wang
Yue
Y
Department of Pathobiology, Chongqing University of Medical Sciences, Chongqing 400016, China. wangyue_26@hotmail.com
Mai
Tao
T
Liu
Ming-fang
MF
Chen
Shu-hui
SH
D017209:Apoptosis / Q000187:drug effects; D001644:Bifidobacterium / Q000737:chemistry*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008070:Lipopolysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D008869:Microtubule-Associated Proteins / Q000235:genetics* / Q000378:metabolism; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects; D000077022:Survivin; D013682:Teichoic Acids / Q000302:isolation & purification / Q000494:pharmacology*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008070:Lipopolysaccharides; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D000077022:Survivin; D013682:Teichoic Acids; D016159:Tumor Suppressor Protein p53; C009900:lipoteichoic acid; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human