In silico and in vitro validation of cinnamaldehyde as a potential cathepsin B inhibitor

Cancer is a leading cause of death worldwide, surpassed only by heart disease. Despite improved diagnosis and treatment, cancer cells still evade normal physiological processes such as apoptosis, metabolism, angiogenesis, cell cycle, and epigenetics. To mitigate the numerous side effects linked to chemotherapy, leveraging natural products emerged as a promising alternative, either alone or in tandem with traditional agents. Cinnamaldehyde, an active ingredient of Cinnamomum cassia's stem bark has emerged as a molecule of research with diverse pharmacological properties. In the present study, we report an in silico potential of cinnamaldehyde (CM) potential as an anticancer agent across thirteen anti-cancer targets in comparison with chlorambucil (CB), docetaxel (DOC), melphalan (MP). Computational tools such as DFT, CHEM3D, molinspiration, vNNADMET, SWISS ADME, admetSAR, galaxyrefine, iGEMDOCK, and DS-Visualizer were employed. Additionally, anti-cathepsin B activity was assessed for cinnamaldehyde and the commercial drugs CB, DOC, MP and the results showed 52.76, 62.41, 72.48 and 65.52 % inhibition respectively which is comparable. The results supported molecular docking using iGEMDOCK. Both in silico and experimental findings substantiate cinnamaldehyde as a promising drug for cancer treatment including metastasis and invasion where cathepsin B involvement is indicated.