Abstract:
Statistics on breast cancer highlights the need to develop new therapeutics that are
natural, safe, and effective. Recent studies have presented the cytotoxic activity of various lactic
acid bacteria against cancer cells. This study determined the cytotoxic effects of the combined
cell-free supernatants (CFS) of Lactiplantibacillus plantarum BS25 and Pediococcus acidilactici
3G3 against the MCF-7 human breast cancer cell line. Seven ratios of the combined CFS from L.
plantarum BS25 and P. acidilactici 3G3 were prepared and subjected to an MTT assay to
determine which ratio exerted the highest cytotoxic effect on the cancer cells. The AA8 Chinese
hamster ovarian cell line, composed of non-malignant cells, was employed as reference. The
manner of cell death was determined using the Annexin Propidium Iodide (Annexin-PI) assay.
The effect of the combined CFS on angiogenesis was also examined through chorioallantoic
membrane (CAM) assay. It was revealed that all seven combined CFS ratios displayed similar
cytotoxic activity against the MCF-7 breast cancer cells. The combined CFS exhibited
significantly higher cytotoxic effects towards the non-cancerous AA8 cell line rather than the
malignant MCF-7 cell line. Most cells undergoing cell death were identified to be in the late
apoptotic stage. Moreover, all combined CFS ratios exhibited anti-angiogenic effects. Hence, the
cytotoxic properties of the combined CFS supports its great potential in the development of
localized treatment of cancer cells.
