Drug-metabolizing enzyme (DME)-mediated pharmacokinetic
resistance
of some clinically approved anticancer agents is one of the main reasons
for cancer treatment failure. In particular, some commonly used anticancer
medicines, including docetaxel, tamoxifen, imatinib, cisplatin, and
paclitaxel, are inactivated by CYP1B1. Currently, no approved drugs
are available to treat this CYP1B1-mediated inactivation, making the
pharmaceutical industries strive to discover new anticancer agents.
Because of the extreme complexity and high risk in drug discovery
and development, it is worthwhile to come up with a drug repurposing
strategy that may solve the resistance problem of existing chemotherapeutics.
Therefore, in the current study, a drug repurposing strategy was implemented
to find the possible CYP1B1 inhibitors using machine learning (ML)
and structure-based virtual screening (SB-VS) approaches. Initially,
three different ML models were developed such as support vector machines
(SVMs), random forest (RF), and artificial neural network (ANN); subsequently,
the best-selected ML model was employed for virtual screening of the
selleckchem database to identify potential CYP1B1 inhibitors. The
inhibition potency of the obtained hits was judged by analyzing the
crucial active site amino acid interactions against CYP1B1. After
a thorough assessment of docking scores, binding affinities, as well
as binding modes, four compounds were selected and further subjected
to
in vitro
analysis. From the
in vitro
analysis, it was observed that chlorprothixene, nadifloxacin, and
ticagrelor showed promising inhibitory activity toward CYP1B1 in the
IC
50
range of 0.07–3.00 μM. These new chemical
scaffolds can be explored as adjuvant therapies to address CYP1B1-mediated
drug-resistance problems.