Anticancer Activity of the Endophytic Fungus <i>Phomopsis</i> sp. Against MCF-7 Breast Cancer Cells: <i>In vitro</i> and <i>In silico</i> Studies

Breast cancer is a major global health concern, increasing the demand for alternative therapeutic sources. Therefore, this study aims to evaluate the anticancer potential of the endophytic fungus Phomopsis sp. from soursop leaves against MCF-7 breast cancer cells. The metabolite profile of Phomopsis sp. was analyzed, and the anticancer as well as apoptotic activity were assessed in both MCF-7 and normal Vero cell lines. The samples were cultivated in yeast malt broth, extracted with ethyl acetate, and separated using column chromatography. The result showed that Brine shrimp lethality test yielded ten fractions (F1–F10), with F1 demonstrating the strongest cytotoxicity (LC50 = 2.33 µg/mL). Antiproliferative assays produced IC50 values of 5.65 µg/mL for MCF-7 and 5.21 µg/mL for Vero cells, with apoptosis confirmed by acridine orange-ethidium bromide staining. Furthermore, Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) identified 38 active compounds in the F1 sample, including known anticancer agents such as cytosporone C, kynurenic acid, maraniol, (-)-caryophyllene oxide, and chalcone. Computational in silico analyses using PASS online, molecular docking, ADMET/pharmacokinetic studies, density functional theory (DFT) analysis, and molecular dynamics (MD) simulations further validated chalcone as a promising anticancer candidate. Chalcone showed favorable ADMET/pharmacokinetic properties and achieved the highest docking score of-8.392 kcal/mol among the compounds tested. MD simulations over 300 ns indicated that chalcone outperformed tamoxifen, with binding energy calculations showing a value of -227.069 kJ/mol compared to -45.598 kJ/mol for tamoxifen. In conclusion, these results underscore the therapeutic potential of endophytic fungi as sources of novel agents for breast cancer treatment. Keywords: Apoptosis, Breast cancer, Phomopsis sp., Molecular dynamics, Quantum chemistry, Density Functional Theory