Bacillus mojavensis postbiotics: transcriptomic and anticancer effects in colon cancer cells

Probiotics have been shown to exert antiproliferative effects on colon cancer cells. While these effects are often attributed to microbiome regulation, they may also result from bioactive metabolites produced by probiotic bacteria. In the present study, we investigated the impact of a cell-free extract, hereafter referred to as a postbiotic, derived from Bacillus mojavensis , a strain isolated from aguamiel (a traditional Mexican beverage). The antiproliferative activity was evaluated in SW480 human colon cancer cells using MTT and crystal violet assays, while antimigratory effects were assessed through a wound-healing assay. In addition, the ability of the postbiotic to counteract inflammatory proliferation was evaluated in SW480 cells treated with lipopolysaccharide (LPS). Biosafety was tested using peripheral blood mononuclear cells (PBMCs) from healthy donors. The results demonstrated that treatment with 25 or 50 µg/mL of B. mojavensis postbiotic reduced the viability of more than 75% of SW480 cells and significantly inhibited cell migration after 24 h. Moreover, the postbiotic decreased LPS-induced proliferation without exerting any cytotoxic effect on PBMCs, underscoring its selectivity toward malignant cells. To elucidate the underlying mechanisms, transcriptomic profiling was performed, revealing extensive modulation of oncogenes and tumor suppressors, with enrichment of PI3K–Akt, MAPK, apoptosis, and cytokine receptor pathways. In conclusion, postbiotics from B. mojavensis isolated from aguamiel exhibit selective anticancer activity by inhibiting proliferation, migration, and inflammation-induced growth in colorectal cancer cells. Transcriptomic findings further support these effects.