Modulation of Caco-2 Colon Cancer Cell Viability and CYP2W1 Gene Expression by Hesperidin-treated Lacticaseibacillus rhamnosus GG (LGG) Cell-free Supernatants

Abstract

Background and Objective: Ensuring colon homeostasis is of significant influence on colon cancer and delicate balance is maintained by a healthy human gut microbiota. Probiotics can modulate the diversity of the gut microbiome and prevent colon cancer. Metabolites/byproducts generated by microbial metabolism significantly impact the healthy colonic environment. Hesperidin is a polyphenolic plant compound well known for its anticancer properties. However, low bioavailability of hesperidin after digestion impedes its effectiveness. CYP2W1 is a newly discovered oncofetal gene with an unknown function. CYP2W1 gene expression peaks during embryonic development and is suddenly silenced immediately after birth. Only in the case of some types of cancer, particularly colorectal and hepatocellular carcinomas, this gene is reactivated and its expression is correlated with the severity of the disease. This study aimed to investigate the effects of hesperidin-treated Lacticaseibacillus rhamnosus GG (LGG) cell-free supernatants on Caco-2 colon cancer cell viability and CYP2W1 gene expression. Methods: Alamar Blue cell viability assay was used to investigate the cytotoxic effect of cell-free supernatant of LGG grown in the presence of hesperidin on Caco-2 cells. To observe the effect of cell-free supernatants of LGG on the expression of CYP2W1 gene, qRT-PCR was performed. Results: Five times diluted hesperidin treated cell-free supernatant (CFS) concentration considerably reduced Caco-2 colon cancer cell viability. Furthermore, CYP2W1 gene expression was similarly reduced following CFS treatments and nearly silenced under probiotic bacteria CFS treatment. Conclusion: The CYP2W1 gene expression was strongly reduced by cell-free supernatants derived from LGG culture, with or without hesperidin. This suggests that the suppression may be due to bacterial byproducts rather than hesperidin. Therefore, the CYP2W1 gene in the case of deregulation of these metabolites may cause CYP2W1-related colon cancer cell proliferation.