Milk fermented by Lactobacillus casei CRL431 administered as an immune adjuvant in models of breast cancer and metastasis under chemotherapy

V. E. MÉNDEZ UTZ; D. PÉREZ VISÑUK; G. PERDIGÓN; A. DE MORENO DE LEBLANC

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

SPRINGER

Lugar: Berlin; Año: 2020 vol. 105

0175-7598

Chemotherapy is the most common treatment for breast cancer and its metastasis; however, it affects the patients? quality of life.Previously, it was demonstrated that milk fermented by Lactobacillus casei CRL431 (probiotic fermented milk (PFM)) exertedbenefits against breast cancer metastasis by modulating the immune response in a mouse model. The aim of this work was toevaluate PFM administration on the side effects of capecitabine and on its anti-tumour/anti-metastatic effects. In vitro, 4T1 breastcancer cells were treated with capecitabine in the presence of immune cells? conditioned media from mice administered withPFM. Cell viability was evaluated by MTT assay. In vivo, BALB/c mice (healthy, bearing breast cancer or with potentialmetastasis) were treated or not with capecitabine and administered with PFM. Blood cell counts, intestinal damages, lunghistology and serum cytokines were evaluated. Results showed that capecitabine?s toxicity on 4T1 cells was improved by theimmune cells from mice that received PFM when the lower dose of capecitabine was evaluated. PFM reduced capecitabine sideeffects in all the mouse models and decreased intestinal mucositis and mortality. PFM administration to mice under chemotherapy maintained the anti-cancer/anti-metastasis effect of capecitabine with similar or decreased values for serum IL-10 and TNF-αand decreased IL-6, a cytokine related to poor prognosis in advanced cancer patients. In addition, PFM by itself reducedmetastasis without side effects and improved the host?s immune response. PFM has a potential to be administered as an immuneadjuvant in patients under chemotherapy without affecting the treatment.