Due to their high content of bioactive compounds with anticancer properties, essential oils (EO) are increasingly viewed as valuable therapeutic strategies in oncology. The aim of this study was to evaluate the chemical composition and anticancer activity of Cedrus atlantica EO (CAEO) and its PEG-400 and Tween 20 formulations. The gas-chromatography (GC) analysis revealed a sesquiterpene-rich profile, with β-himachalene (39.32%) as the major constituent, followed by α-Himachalene (16.76%) and γ-Himachalene (12.92%). The cytotoxicity studies, performed using Alamar Blue assay on normal HaCaT human keratinocytes and A375 human melanoma and HT-29 colorectal carcinoma cell lines, revealed that CAEO displayed minimal toxicity on HaCaT cells, while significantly reducing A735 and HT-29 cell viability, at any of the concentrations tested. The PEG- and Tween-based formulations of CAEO exhibited the same effect on cell viability as the simple water dispersion of CAEO. The immunofluorescence-based examination of cellular morphology suggested that CAEO induces apoptosis in both cancer cell lines: A375 and HT-29; this apoptosis-related mechanism was further supported by the caspase-3/7 assay, which revealed a significant increase in caspase-3/7 activity after CAEO treatment. To further investigate the underlying mechanism, the JC-1 staining and high-resolution respirometry assays demonstrated that CAEO induces mitochondrial membrane depolarization and reduced mitochondrial active respiration (OXPHOS). Molecular docking further indicated that isoledene and β-himachalene exhibit the highest predicted affinity for PI3Kγ, suggesting a potential involvement of PI3K-related signaling in the pro-apoptotic activity of CAEO. Together, these results suggest that CAEO induces apoptosis through a mitochondria-mediated mechanism.

Anti-apoptotic Bcl-2 family proteins (Bcl-2, Bcl-xL, and Mcl-1), are often overexpressed in cancer, which aids tumor growth and treatment resistance. As a result, these proteins are excellent candidates for novel anticancer drugs. Within this study a virtual library of betuline derivatives was built and screened for possible Bcl-2, Bcl-XL, and Mcl-1 inhibitors. For every target, molecular docking simulations were performed using two different engines (AutoDock Vina and Glide). The ligands that most frequently appeared among the top candidates were shortlisted after comparing the top-20 hits from both docking scoring functions. To assess binding stability, five of these promising compounds were chosen and run through 100 ns molecular dynamics (MD) simulations in complex with every target protein. Key persistent intermolecular contacts were identified from MD contact frequency histograms, and stability was evaluated using root-mean-square deviation (RMSD) profiles of protein–ligand complexes following equilibration. Additionally, Prime MM-GBSA binding energies (ΔG_bind) for the 15 docked complexes were computed, and ligand efficiency was reported. Two substances, BOxNaf1 and BT3, stood out among the screened derivatives as the most stable binders to all three Bcl-2 family targets according to the dual docking and MD analysis approach. When the MM-GBSA and RMSF/rGyr data are considered alongside docking and MD stability, BOxNaf1 and BOxPhCl1 emerge as the most compelling dual/multi-target candidates, whereas BT3, though MD stable, shows weaker MM-GBSA energetics and is retained as a lower-priority backup chemotype.

Cancer remains a leading cause of global mortality, entailing the exploration of novel therapeutic agents from natural sources. This study evaluated the in vitro anti-cancer potential of essential oils (EOs) extracted from the needles of Pinus sylvestris L. (Scots pine) and Picea abies (L.) H. Karst. (Norway spruce). GC–MS analysis revealed that both EOs are rich in monoterpenes; the primary constituents were α-pinene (35.27%) for Pinus sylvestris sylvestris EO (Pinus EO) and β-pinene (31.40%) for Picea abies EO (Picea EO). Cell viability assay (Alamar Blue) demonstrated that both EOs exert a dose-dependent cytotoxic effect across all tested malignant lines: melanoma (A375), colorectal adenocarcinoma (HT-29), and pancreatic adenocarcinoma (PANC-1). Notably, Pinus EO consistently displayed higher potency toward cancer cells when compared with normal keratinocytes (HaCaT), with the highest selectivity noticed in HT-29 cells. Immunofluorescence analysis revealed morphological changes consistent with apoptosis, such as nuclear condensation, DNA fragmentation, and the disruption of the β-actin cytoskeleton. High-resolution respirometry indicated that the EOs increase LEAK respiration, while also significantly reducing the oxidative phosphorylation (OXPHOS) efficiency. Furthermore, network pharmacology and molecular docking predicted EP300 as a common hub target for both EOs, with β-caryophyllene showing the most favourable predicted binding affinity among the investigated constituents. Overall, these preliminary in vitro and in silico findings support the further investigation of Pinus EO and Picea EO as potential candidates for the development of future adjuvant strategies in cancer therapy.