Anti-tumor effects of Bacteroides fragilis and Bifidobacterium bifidum culture supernatants on mouse breast cancer

BACKGROUND AND OBJECTIVESBreast cancer is one of the most important causes of cancer related morbidity and mortality in the world. Along with genetic, environmental factors also play a multifaceted role in the development of disease. Bacteroides and Bifidobacterium, as microbial flour, play pivotal role against breast cancer development in vivo and in vitro.MATERIALS AND METHODSIn this study we evaluated the anti-proliferative and anti-tumor effects of Bacteroides fragilis (F.S),Bifidobacterium bifidum (B.S) and Bifidobacterium bifidum + Bacteroides fragilis supernatants (B.F.S) in in vivo and in vitro model of ۴T۱ cell line breast cancer. Different doses of bacterial supernatants assessed in both model. The effects of culture supernatants were determined by MTT [۳-(۴,۵-dimethylthiazol-۲-y-۲,۵-diphenyltetrazolium bromide] assay. Tumor size/volume, cell growth inhibition and cytokine secretion were assessed.RESULTS AND DISCUSSIONOur results indicated that the relative tumor volume significantly increased in the mice receiving intratumoral (I.T) PBS (p<۰.۰۵). Surprisingly, ۳ out of the ۴ mice were cleared from the tumor thoroughly in ۱۰–۲۵ days after intratumoral administration of B.F.S. Quantification of cytokines clearly showed that the mice receiving intratumoral B.F.S significantly secreted higher interferon γ (IFN-γ) and) level and the other side, secreted lowest IL-۱۰ level compared with the other groups (p<۰.۰۵). Overall, our findings indicated that intratumoral administration of B.F.S effectively inhibited the growth of breast tumors through induction of necrosis and suppressing proliferation and angiogenesis.CONCLUSIONCollectively, our study showed that bacterial supernatants (F.S, B.S, F.B.S) can act as potent Anticancer agents, they can inhibit the growth of breast cancer cells in vitro, on the other side, they reduce the tumor volume and the recovery process increases in mice bearing breast tumor.

کلیدواژه ها:

Breast cancer ، Flour microbiota ، Bacteroides fragilis ، Bifidobacterium bifidum ، culture supernatant