Combination of Probiotics and Resveratrol to Target Drug Resistance in Breast Cancer: An In vitro and In vivo Study

Background: Probiotics exhibit significant activity in the immune system by activating multiple immune mechanisms. Resveratrol is a non-flavonoid polyphenol. It has various pharmacological effects, including anti-oxidative, anti-inflammatory, anti-proliferative, and anti-angiogenesis effects. Objectives: The present study investigates the potential immunomodulatory and antitumor activity of the combination treatment of probiotics and resveratrol in sensitive and cisplatin-resistant breast cancer. Methods: In the in vivo study, tumor-bearing mice received one of the following treatments: 2.5*10⁸CFU/ml probiotics, 50 mg/kg resveratrol, the combination of probiotics and resveratrol, vehicle, or cisplatin. Balb/C mice were inoculated with sensitive EMT6/P and cisplatin resistance EMT6/CPR cancer cell lines, and in vivo antitumor activity was evaluated. Results: The antiproliferative activity of the probiotics, resveratrol, and their combination treatments was assessed using an MTT assay to evaluate lymphocyte proliferation activity. LDH colorimetric assay was conducted to measure the effectiveness of the treatments on the activity of natural killer cells. Nitro blue tetrazolium assay and neutral red method were used to evaluate macrophage function. Conclusion: The combination treatment showed an enhanced effect in splenic lymphocyte proliferation, macrophage function, phagocytosis, and pinocytosis in both cell lines. A significant reduction in tumor size and weight in EMT6/P and EMT6/CPR-bearing mice occurred. Hence, the combination treatment of probiotics and resveratrol was found to have a valuable activity against sensitive and cisplatin-resistant breast cancer cells and might act as a stimulator of the immune system. Therefore, the combination of probiotics and resveratrol deserves further analysis to be used in cancer prevention and treatment.