Selaginella bryopteris-derived silver nanoparticles against ovarian cancer cells: green synthesis, in vitro anticancer activity, and exploratory in silico analysis

Introduction – Chronic hormonal imbalances and associated symptoms characterize ovarian cancer. PARP-1 inhibitors, such as olaparib and ruparib, are used to treat it, but new drugs are needed to overcome toxicity and resistance issues. PARP inhibition in BRCA1/2-mutated cancer cells leads to apoptosis. Methods – We synthesized silver nanoparticles (AgNPs) from S. bryopteris leaf extract, using it as a stabilizing and reducing agent. The extract was added to the AgNO3 solution and maintained at room temperature for 24 h. The AgNPs were characterized using various techniques, including UV-visible and FTIR spectroscopy, SEM, EDX, Transmission Electron Microscopy, and ICP-MS analysis. The stability of AgNPs was evaluated under different pH and temperature conditions, and their anticancer activity was evaluated against SKOV3 and OVCAR-3 ovarian cancer cells using MTT assay, while IOSE80 cells were used as a non-tumorigenic ovarian epithelial cell model. The binding mechanism of phytochemicals from Selaginella bryopteris to PARP-1 was investigated using computational methods. Results – Selaginella bryopteris-derived AgNPs showed stronger cytotoxicity than the plant extract against SKOV3 and OVCAR-3 ovarian cancer cells, with IC50 values of 9.56 and 10.45 μg/mL, respectively, and lower toxicity toward IOSE80 cells (IC50= 19.75 μg/mL). AgNP treatment increased intracellular Reactive Oxygen Species levels, suggesting oxidative-stress-mediated cell death, while in silico analyses highlighted rhamnetin as a promising PARP-1-interacting phytoconstituent. Discussion – The anticancer properties of AgNPs from S. bryopteris were investigated using analytical, pharmacological, and computational methods. Results showed the stability of AgNPs and their effectiveness against ovarian cancer cells. AgNPs from the S. bryopteris leaf extract showed stronger anticancer activity than the plant extract alone, whereas their possible use as targeted drug delivery or controlled-release platforms remains a future perspective requiring dedicated experimental investigation.