Molecular docking studies of Brucein D as a potential inhibitor of the Bcl-2 anti-apoptotic protein

Background: Brucein D (BrD), a quassinoid isolated from Brucea javanica fruit, reportedly demonstrates anti-tumor activity. Bcl-2 is an anti-apoptotic protein that inhibits apoptosis and leads to cancer progression. This study aims to evaluate the inhibitory effect of BrD against the anti-apoptotic protein Bcl-2 by molecular docking study. Methods: We investigated the activity of BrD against Bcl-2 through molecular docking in silico compared to the chemotherapeutic drugs doxorubicin and docetaxel. Molecular docking analysis was conducted using the Lipinski rule of five drug-likeness analyses, PASS Online prediction, PyRx v0.8, Discovery Studio DS BIOVIA 2016 v16, and PyMol v2.4.Results: Current results show that BrD is qualified as a drug and can pass cell membranes without toxicity. The PASS prediction also shows that BrD can be activated as an anti-neoplastic inside the human body with Pa higher than Pi. BrD can make a constant and stable bond to Bcl-2 with a binding energy of -8.3 kcal/mol, almost equal to doxorubicin and docetaxel. BrD can form six types of hydrogen bonds that show stability to temperature and pressure.Conclusion: BrD has shown to be a promising alternative for an anti-cancer drug by inhibiting the Bcl-2 anti-apoptotic protein with low toxicity in normal cells.