Effects Of The Metabolites Of Streptococcus Gallolyticus On The Growth Of Colon Cancer Cells And Its Mechanism

Backgrounds: Colorectal cancer is one of the most common malignant tumors in the world.Its occurrence and development are not only related to genetic factors,envriromrntal factors,diet and lifestyle,but also closely related to changes in intestinal microecology and microenvironment.Recent studies have found that streptococcus gallolyticus subsp.gallolyticus is closely related with the occurrence of colorectal cancer,but its specific mechanism and effect are still unknown.Objective: To observe the effect of the metabolites of Streptococcus gallolyticus on the proliferation and migration of human colon cancer cells,and to explore the possible role of Streptococcus gallolyticus infection in the development of colon cancer,and to explore the possible mechanism.Method:The aseptic sampling sampling activities,amplification and extraction solution of Streptococcus gallolyticus bacterial metabolites,with the blank group(A),healthy intestinal flora group(B),Bifidobacterium group(C),Streptococcus gallolyticus group(D)and Bifidobacterium + Streptococcus gallolyticus group(E)as control,using the bacterial metabolites treatment of colon cancer cell SW620.Cell count and CCK-8 test were used to detect the proliferation of tumor cells in different groups.The migration ability of tumor cells in different groups were detected by scratch test.The expression of protein level of the tumor related important molecule ?-catenin was detected by Western blot.The expression of c-mycRNA in the downstream of WNT signal pathway was detected by Real time PCR.Result: The cell count showed that the number of tumor cell proliferation was significly higher in group D and group E than that in group A? group B and group C(P<0.05).CCK-8 test showed that the celluar activities was significly higher in group D and group E than that in group A,group B and group C(all P<0.05);Cell migration experiments showed that the recovery rate of cell scratch in group D and group E was significantly faster than that in group A,group B and group C(all P<0.05).Western blotting showed that the protein level of ?-Catenin in WNT signaling pathway in group D and E was significantly higher than that of group A,B and C,and real-time quantitative PCR analysis showed that the expression of c-myc RNA,an important molecule downstream of WNT signal pathway,was significantly higher in group D and group E than in the other three groups(P<0.05).Conclusion:Streptococcus gallolyticus can enhance the proliferation and migration ability of colon cancer cell SW620 through its metabolites and improve the expression levels of ?-Catenin and c-myc,suggesting that the mechanism may be through the activation of Wnt/?-Catenin signal pathway.Moreover,the metabolic products of bifidobacterium can not inhibit the enhancement of the proliferation and migration capacity of colon cancer cells by the metabolic products of Streptococcus gallolyticus.