Inhibition of Proliferation and Invasion of Human Colon Carcinoma Cell Line (Caco-۲ cells) by Cell-Free Supernatants from Lactobacillus Rhamnosus and Lactobacillus Acidophilus

Background & Objective:  Colorectal cancer (CRC) is one of the most common types of cancer in the world and is considered a leading cause of cancer-related death. The present study aimed to investigate the inhibitory effect of lactobacillus acidophilus (PTCC ۱۶۴۳) supernatant (LAS) and lactobacillus rhamnosus (PTCC ۱۶۵۷) supernatant (LRS) on the growth and invasiveness of the human colon carcinoma cell line (Caco۲) in-vitro.  Materials & Methods:  In this study, the antiproliferative activity and anti-invasion potential of LAS and LRS were determined by MTT and transwell chamber assays, respectively. Furthermore, the expression of mitochondrial membrane potential-۹ (MMP-۹) and matrix metalloproteinase-۱۲ (MMP۱۲) genes were analyzed by real-time PCR. Results:  The results of the MTT assay indicated that LAS and LRS had cytotoxic effects on Caco-۲ cell proliferation at a concentration of ۲۵% and higher after ۷۲ hours (p<۰.۰۰۰۱). Thus, the minimum concentrations (۲۵%) of supernatants were chosen for further experiments. LRS and LAS could significantly suppress the invasiveness of cells, p= ۰.۰۲۸ and p=۰.۰۰۲, respectively. Also, the expression of MMP۱۲ was significantly increased in cells when treated with LAS (p<۰.۰۰۱), whereas LRS had no significant effect on MMP-۱۲ expression. Furthermore, the expression of MMP-۹ was statistically decreased in cells treated with both supernatants (p<۰.۰۰۰۰۱). Conclusion:  In general, it was shown that LAS and LRS exert anti-cancer activity against the growth, invasion, and metastasis of Caco۲ cells.

Keywords:

Lactobacillus , Colon cancer , Probiotic , Invasion assay , Metastasis