[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).

Conclusion: 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.