Lactobacillus rhamnosus-derived postbiotics inhibit proliferation, invasion, and EMT-associated signalling in colorectal cancer cells.

OBJECTIVES

Probiotics and their metabolites (postbiotics) have gained increasing attention because of their potential anticancer properties. This study aimed to evaluate the effects of postbiotics derived from Lactobacillus rhamnosus (LR) on colorectal cancer (CRC) cells and to investigate their potential effects on malignant phenotypes and epithelial-mesenchymal transition (EMT)-associated signalling.

METHODS

Sterile LR culture filtrates were applied to SW480 colorectal cancer cells and highly invasive SW480-I5 cells. Cell viability, proliferation, migration, invasion, and apoptosis were assessed. The expression of EMT-associated transcription factors, mesenchymal markers, and matrix metalloproteinase 3 (MMP3) was also evaluated to explore the underlying molecular mechanisms.

RESULTS

LR culture filtrates reduced cell viability in a dose-dependent manner and significantly suppressed cell migration and invasion, with more pronounced effects observed in highly invasive SW480-I5 cells. LR treatment also inhibited cell proliferation and promoted apoptosis in both cell lines. Mechanistically, LR filtrates downregulated the EMT-associated transcription factors ZEB2, Snail, and Twist, as well as the mesenchymal markers N-cadherin and Vimentin, and reduced MMP3 expression.

CONCLUSIONS

LR-derived postbiotics exert inhibitory effects on CRC-associated malignant phenotypes by suppressing cell viability, proliferation, migration, and invasion while promoting apoptosis and modulating EMT-associated signalling. These findings suggest that LR-derived postbiotics may represent promising adjunctive candidates for CRC modulation.