Drug repurposing identifies novel Wee1 kinase inhibitors for triple negative breast cancer therapeutics

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with limited treatment options. Wee1 kinase, a critical regulator of the G2/M checkpoint and DNA replication, is a promising therapeutic target. However, dose dependent associated toxicities of current Wee1 inhibitors like adavosertib highlights the need for safer alternatives. Drug repurposing offers an efficient strategy to rapidly identify existing drugs for new applications. In the current study, we screened 8824 molecules from the Drug Bank database using machine learning, molecular docking and molecular dynamic approaches to identify potential Wee1 inhibitors. The KRR-based machine learning model effectively predicted binding energies, identifying 81 potential Wee1 kinase inhibitors, with binding energies of ≤ -9 kcal/mol. Rank-based screening using ligand efficiency indices, along with binding scores and poses, identified five lead candidates. Subsequent enzymatic and cytotoxicity assays identified two top hits, adomeglivant and dactolisib. Additionally, dose dependent suppression of pCdc2, together with CETSA, validated adomeglivant and dactolisib as Wee1 inhibitors. Moreover, both drugs promoted apoptosis and nuclear disintegration in TNBC cell lines. The study further examined the synergistic effects of combining adavosertib or dactolisib with cisplatin. These combinations demonstrated significant enhanced efficacy over monotherapy, with a 3- to 11-fold reduction in IC₅₀ values. Optimal dosing ratios of 1:1 for adavosertib-cisplatin and 1:2 for dactolisib-cisplatin were identified, underscoring effective, dose-dependent synergy in these combinations. Dactolisib and adomeglivant show promise as Wee1 kinase inhibitors in TNBC, with dactolisib exhibiting superior potency, and their synergistic potential in combination therapies, such as with cisplatin, highlighting avenues for future clinical development.