Design and synthesis of new Thieno[2,3-d]pyrimidine-based derivatives as anti-breast cancer: Biological evaluation, PIM-1 kinase inhibition, and in silico studies

This study primarily aimed to develop and evaluate new thieno[2,3-d]pyrimidine derivatives with potential anticancer properties through a comprehensive process of design and synthesis. Using a variety of spectroscopic methods, the chemicals produced were thoroughly analyzed. The cytotoxic effects of the derivatives on the MCF-7 breast cancer cell line were examined. Compound 15 demonstrated the strongest anticancer activity, with IC₅₀ value of 34.49 ± 1.32 μM, compared to doxorubicin (IC₅₀ = 34.20 ± 0.28 μM). The most potent derivatives were assessed for their ability to suppress PIM-1 kinase activity. PIM-1 inhibitory activity of compounds 8, 12, 15, and 17 was evaluated compared to staurosporine. The results showed potent to moderate activity with IC₅₀ values of 0.771 ± 0.028, 1.332 ± 0.049, 0.212 ± 0.008, and 2.66 ± 0.099 μM, respectively, and IC₅₀ = 0.47 ± 0.017 μM for staurosporine. Moreover, a scratch wound healing assay revealed that compound 15 significantly impeded cell migration. Additionally, compound 15 displayed a marked increase in Bax expression by 2.35-fold and caspase-3 levels by 1.12-fold in MCF-7 breast cancer cell line. On the other hand, it caused a downregulation of Bcl-2 level by 0.31-fold. Additionally, the binding relationships produced between compound 15 and the PIM-1 kinase active site were investigated using molecular docking experiments, providing insights into their inhibitory potential. Finally, to further assess the stability of the compound 15-PIM-1 kinase complex and validate the docking results, molecular dynamics (MD) simulations were performed.