Iranian Journal of Medical Microbiology

Breast cancer is one of the leading causes of cancer-related deaths among women worldwide. The resistance of advanced tumors to conventional treatments highlights the need for alternative therapies. Apoptosis, regulated by key genes like BAX (pro-apoptotic) and BCL2 (anti-apoptotic), plays a crucial role in controlling cancer cell proliferation. This study investigates the effects of Bacillus licheniformis extract, isolated from Hoz Sultan Lake in Qom Province, on the expression of BAX and BCL2 genes in the MCF-7 breast cancer cell line. MCF-7 cells were treated with the bacterial extract at various concentrations, and cell viability was assessed using MTT assay. RNA extraction, cDNA synthesis, and Real-Time PCR were performed to evaluate gene expression levels. Statistical analysis was conducted using an independent t-test, with p-values < 0.05 considered significant. The extract significantly increased BAX expression (p < 0.05) over 24, 48, and 72 hours, while BCL2 expression decreased initially but showed a slight increase after 48 hours. IC50 values decreased over time, indicating time-dependent cytotoxicity. The Bacillus licheniformis extract demonstrates potential as a novel anti-cancer agent by promoting apoptosis in MCF-7 cells. Future studies on in vivo models and protein-level validation are recommended to explore its therapeutic potential.