Probiotic-enhanced chemotherapy: Lactobacillus fermentum synergizes with vincristine to induce apoptosis via dual pathway activation in human cancer cells
Abbas Asoudeh-Fard, Mohadeseh Asoudeh-Fard, Asghar Parsaei
Abstract
BACKGROUND: Probiotics, particularly Lactobacillus species, show promise as adjuvants in cancer therapy due to their pro-apoptotic effects. This study investigated the synergistic impact of Lactobacillus fermentum (Ab.RS23) and vincristine sulfate on colorectal (HT-29) and breast (MCF-7) cancer cells. METHODS: Cells were treated with vincristine, L. fermentum, or both. Cell viability was measured by MTT assay. Apoptosis was analyzed via Annexin V-FITC/PI flow cytometry. Gene expression changes were evaluated by RT-qPCR. RESULTS: Co-treatment reduced the IC₅₀ of vincristine by 8-fold in HT-29 and 13-fold in MCF-7 cells. Apoptotic signaling was enhanced, with pro-apoptotic pathways upregulated and survival pathways downregulated. CONCLUSION: L. fermentum enhanced vincristine-induced apoptosis and reduced the required drug dose, which may contribute to lowering vincristine-associated toxicity. These findings require confirmation through in vivo studies.