Effect of extracellular vesicles of Lactobacillus rhamnosus GG on the expression of CEA gene and protein released by colorectal cancer cells

Almost all living cells secret nano-sized structures enclosed by the lipid bilayer called extracellular vesicles (EVs) into their extracellular milieu. These EVs play important roles in several physiological processes as a cargo delivery system. In probiotics, EVs are the main communication tool with the host. The present study aimed to assess the effect of EVs originated from Lactobacillus rhamnosus GG on the Carcinoembryonic antigen (cea) gene expression and protein (CEA) synthesis in the SW480 and HT-29 cell lines.

Different concentrations of Lactobacillus rhamnosus GG EVs were applied on the SW480 and HT-29 cell lines. The MTT assay, Real-Time PCR, and ELISA analysis methods were exploited to explore the cell viability and the expression level of the cea gene in comparison with the β-actin gene as the control.

The two concentrations of 80 and 100 μg/ml of Lactobacillus rhamnosus GG EVs considerably affected the anti-proliferation and increased the amount of both CEA mRNA and protein (p < 0.05).

Our findings showed that EVs of Lactobacillus rhamnosus GG could induce the gene expression and protein synthesis of CEA. Also, they reduced the cell proliferation of HT29 and SW480. Thus, probiotics such as EVs of Lactobacillus rhamnosus GG could be useful for preventing colorectal cancer.