Caryophyllene Oxide, a Bicyclic Terpenoid Isolated from Annona macroprophyllata with Antitumor Activity: In Vivo, In Vitro, and In Silico Studies

The Annona genus contains some species used in Mexican traditional medicine for the treatment cancer, including Annona macroprophyllata (A. macroprophyllata). The present study aimed to investigate the anticancer activity of caryophyllene oxide (CO) isolated from A. macroprophyllata using in vivo, in vitro, and in silico approaches. The identification of CO was performed using gas chromatography-mass spectroscopy and NMR methods. Antilymphoma activity was evaluated in male and female Balb/c mice inoculated with U-937 cells. Cytotoxic activity was evaluated using the WST method and flow cytometry was used to determine the type of cell death. Acute oral toxicity was determined, and a molecular docking study was performed using target proteins associated with cancer, including, HMG-CoA, Bcl-2, Mcl-1, and VEGFR-2. Results showed that CO exhibited significant antilymphoma and cytotoxic activities, and its effects were comparable to MTX. In addition, flow cytometry showed that the anticancer activity of CO could be mediated by the induction of late apoptosis and necrosis. The result for the acute oral toxicity of CO was classified in category 4, suggesting it is low risk. Finally, molecular coupling studies showed that CO had more affinity for the enzymes HMG-CoA reductase and Bcl-2. Our study provides evidences that CO is a potential anticancer agent for the treatment of histiocytic lymphoma.