EFFECT OF MILK FERMENTED BY Lactobacillus casei CRL431 ADMINISTERED AS IMMUNE ADJUVANT AGAINST BREAST CANCER METASTASIS UNDER CHEMOTHERAPY TREATMENT IN A MURINE MODEL

DE MORENO DE LEBLANC, ALEJANDRA; MENDEZ UTZ, VIRGINIA EMILCE; PERDIGÓN, GABRIELA

San Miguel de Tucumán

Encuentro; LXVII REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INMUNOLOGÍA; 2019

Chemotherapy is useful to treat breast cancer (BC) metastasis; however,it affects the patients? quality of life. Previously, it was demonstrated thatmilk fermented by Lactobacillus caseiCRL431 (probiotic fermented milk, PFM) exerted benefits against BC metastasisby modulating the immune response in a mouse model. Aim: To evaluate PFMadministration on the side effects of capecitabine (CAP) and on BC metastasis treatmentin mice. Methods: In vitro, 4T1 BCcells were treated with CAP in presence of immune cells from mice administeredPFM or milk. Cell viability was evaluated by MTT assay. In vivo, BALB/c mice (healthy or with BC metastasis) were treatedor not with CAP and administered PFM or milk. Blood cell counts, smallintestine and lung histology and serum cytokines were evaluated. Results: Thetoxicity of CAP on 4T1 cells (30% of viability loss) was not affected by theimmune cells from mice received PFM. PFM administration to mice reduced CAPside effects in both healthy and metastatic animals; improved the count ofblood cells, and decreased intestinal mucositis. CAP treatment decreased thelung metastasis and it was associated to decreases of IL-10, TNF-alpha, IFN-gammaand IL-17. PFM administration to mice under chemotherapy maintained the CAP?seffect with similar or decreased values for these cytokines. In addition, PFMby itself reduced metastasis without side effects and improved the host?simmune response. Conclusions: PFM has potential to be administered as immuneadjuvant; can decrease side effects in patients under chemotherapy withoutaffect the treatment