The High Anti-cytotoxic Effects of Novel Lactobacillus Plantarum HBM-IAUF-1 and Lactococcus Lactis HBM-IAUF-8 against SK-BR-3 Breast Cancer Cell Line

Introduction: Recently, breast cancer therapy is challenging worldwide. The probiotics could be used as an alternative for breast cancer prohibition and treatment among which Lactic Acid Bacteria, LAB, have beneficial effects on host health. Materials and methods: Lactic acid bacteria were isolated from yogurt and cheese samples using bacterial culture on MRS broth and MRS agar. Identification of LAB was carried out by macroscopic, microscopic, and molecular analysis. Using MTT assay, the cytotoxicity of LAB on SKBR3 cancer cells was investigated with bacterial concentrations of 100, 250, 500, and 1000 μg/ml. Results: The molecular analysis showed that the two isolates obtained in this study were related to the Lactococcus lactis sp. They were named Lactobacillus plantarum HBMIAUF1 and Lactococcus lactis HBMIAUF8 and their 16srDNA genome sequences were deposited in GenBank, NCBI under the accession numbers of MG757680 and MG757734, respectively. The Lactobacillus plantarum HBMIAUF1 showed the highest cytotoxicity on SKBR3 cancer cells at the maximum time of 72 hours at the concentration of 1000 μl/ml. Also, Lactococcus lactis HBMIAUF8 showed the highest cytotoxicity at the maximum time of 72 hours at the concentration of 500 μl/ml. Discussion and conclusion: This is the first report of identifying the novel lactococcus lactis strains from traditional Iranian dairy products that had cytotoxic effects on breast cancer SKBR3 cells. The use of organic dairy products and the increasing of probiotics applications in the food industry could be an asset in cancer prohibition as well as advantageous in food and medical biotechnology.