Computational and Molecular Profiling of the Anticancer Properties of Thuja occidentalis L. From Southern Punjab

Breast cancer is the most commonly diagnosed cancer worldwide. Thuja occidentalis L., a medicinal plant native to Southern Punjab, Pakistan, is evaluated for its potential anticancer properties through a combination of computational and experimental approaches. A comprehensive screening identified 87 bioactive compounds, from which four isothujol, p-coumaric acid, cedrol, and kaempferol were selected for further analysis on the basis of their oral bioavailability and drug-likeness properties. Molecular docking studies indicated strong binding affinities between these compounds and key breast cancer-related targets, including PARP1, ESR1, MDM2, EGFR, and HIF1A. A Venn diagram and protein-protein interaction (PPI) network analysis revealed 16 common targets that are likely involved in the plant's anticancer effects. KEGG pathway and Gene Ontology (GO) analyses identified 26 cancer-related pathways, including breast cancer, estrogen signaling, and PI3K-Akt signaling pathways. Molecular docking showed binding affinity ranges between -6.2 and -9.6 kcal/mol. The cytotoxic effects of two T. occidentalis extracts, ethyl acetate and n-hexane, were assessed using the MCF-7 breast cancer cell line. The ethyl acetate extract exhibited a dose-dependent cytotoxic effect, with significant inhibition at concentrations as low as 25 µg/mL, whereas the n-hexane extract showed limited activity. Liquid Chromatography-Mass Spectrometry (LC-MS) revealed the presence of key bioactive compounds, such as thujone, cedrol, kaempferol, and quercetin, known for their anticancer properties. In silico studies also suggested that isothujol may induce cancer cell apoptosis by activating the unfolded protein response (UPR) pathway and modulating pro-apoptotic factors. Overall, this study provides valuable insights into the molecular mechanisms underlying the anticancer effects of T. occidentalis, highlighting its potential as a source of therapeutic agents for breast cancer treatment. Further experimental validation is warranted to confirm these findings.