Aims: Lactobacillus sp. has capability of producing an array of bioactive metabolites that exhibit probiotic effects. Therefore, the objective of this study was to determine the cytotoxicity effect of proteinaceous postbiotic metabolites (PPM) produced by Lactobacillus plantarum I-UL4 cultivated in different media composition on MCF-7 breast cancer cell. Methodology and results: L. plantarum I-UL4 was cultivated in yeast extract and modified de Man, Rogosa and Sharpe broth containing Tween 80 (CRMRS+T80) or without Tween-80 (CRMRS-T80). Human breast adenocarcinoma cell (MCF-7) was employed as cancer cell in this study. Cytotoxicity and antiproliferative effects of PPM were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl Tetrazolium Bromide assay and Trypan Blue Dye Exclusion assay, whereas Acridine Orange/Propidium Iodide staining was employed to determine the cytotoxicity mechanism. PPM produced in CRMRS+T80 exerted cytotoxicity in a time and dose dependent manner that was selective towards MCF-7 cancer cell. Profound cytotoxicity with the lowest IC50 concentration of 10.83 µg was detected at 72 h of incubation, whereas the most potent antiproliferative effect revealed by the lowest viable cell population was observed at 24 h of incubation. PPM cultivated in CRMRS+T80 induced 80.87% of apoptotic MCF-7 cells at 48 h of incubation. Conclusion, significance and impact of study: PPM of L. plantarum I-UL4 cultivated in different media composition induced different levels of MCF-7 cancer cell death. The percentage of apoptotic MCF-7 cells treated with PPM cultivated in CRMRS+T80 increased significantly (p < 0.05) from 24 to 48 h of incubation. The results obtained in this study have revealed the potential of PPM produced by L. plantarum I-UL4 as human health supplement and as anticancer preventive agent. Keywords: Lactobacillus plantarum I-UL4; cytotoxic effect; proteinaceous postbiotic metabolites; media composition; breast cancer
Lactobacillus ; Probiotics

Introduction: Cytokine immunotherapy such as Interleukin-27 (IL-27) has been foreseen as a promising alternative anti-cancer treatment. Thus, this study aimed to investigate whether IL-27 gene therapy regulates crosstalk between breast cancer cells and macrophages in the sense of pro-apoptotic activities. Methods: This study has led to the development of recombinant pcDNA3.4-IL27. The recombinant pcDNA3.4-IL27 was transfected into 4T1 murine mammary carcinoma cells alone and co-culture of 4T1 with M2 macrophages. The successful expression of IL-27 in the cells were determine through the immunofluorescence staining and detection of CD206, M2 macrophages marker. Apoptotic effects of pcDNA3.4-IL27 were assessed through MTT assay, Annexin V flow cytometer analysis, and AO/PI dual staining. Results: Our findings shows that pcDNA3.4-IL27 has the ability to induce apoptosis in both of the cell group and performs better in the co-culture of 4T1 with M2 macrophages compared to 4T1 cells alone. PcDNA3.4-IL27 induced apoptosis through the altered cell morphology and reduction in the number of viable cells. Conclusion: These data demonstrate that pcDNA3.4-IL27 has the ability to induce apoptosis in both 4T1 cell alone and co-cultured 4T1 with M2 macrophages. Thus, could serve as a potential anti cancer candidate against breast cancer.