Probiotic Lactobacilli Decrease Invasion of Metastatic Human Colon Cancer Cells In Vitro

Abstract

Colon cancer metastasis involves loss of intercellular junctions and cell invasion through the colonic epithelial basement membrane, a process mediated by matrixmetalloproteinases (MMP). Probiotic bacteria have been shown to improve colonic epithelial barrier function and decrease MMP activity suggesting anti‐metastatic potential. The objective of this study was to explore anti‐metastatic activity of probiotics Lactobacillus casei (L. casei) and Lactobacillus rhamnosus (L. rhamnosus) in terms of decrease in cell invasion. This was assessed by an in vitro assay, measuring the invasion of metastatic human colon cancer cell line HCT‐116 through Matrigel‐coated membranes in Boyden chambers. HCT‐116 cells were plated on top of the membrane with probiotic CFS from either L. casei or L. rhamnosus at 25% (v/v) in DMEM. Bacterial growth medium (MRS) at 25% (v/v) in DMEM was used as the control. Cell invasion was measured after 24 h of treatment; by fixing, staining and counting the cells present on the bottom side of the membrane. Treatment of HCT‐116 cells with CFS from L. casei and L. rhamnosus resulted in a significant decrease in cell invasion by 72% +/− 4.25 and 50% +/− 17.65 respectively, of control. These data indicate that probiotic CFS contain anti‐metastatic bioactive compounds that may be contributing to the decrease in cell invasion in vitro. Funding source: Texas State University Research Enhancement Program.Grant Funding Source: Texas State University Research Enhancement Program