Isobavachalcone induces apoptosis of colorectal cancer cells mediated by interaction with survivin: Experimental and theoretical analyses

Abstract

Isobavachalcone (IBC) as a bioactive chalcone isolated from the seeds of Psoralea corylifolia Linn has shown promising anticancer activities. However, its main anticancer mechanism in colorectal cancer cells has not been well-explored. Recently, the interaction of therapeutic compounds with survivin, an antiapoptotic marker, has been indicated to be a potential approach for advancing anticancer compounds. Therefore, in this study, IBC was evaluated for its anticancer activities against metastatic colorectal adenocarcinoma, LoVo, followed by exploring its interaction with survivin. It was observed that incubation of the human LoVo colorectal cancer cells with the IBC at 24 h resulted in a significant reduction in cell viability with an IC50 of about 35 µM as well as a significant membrane damage. Also, it was deduced that IBC could result in the formation of excessive ROS, lipid peroxidation, reduction of SOD/CAT activity, as well as downregulation of Nrf2 and HO-1 mRNA levels. Further studies showed that IBC could induce MMP reduction, cytochrome c (Cyt c) release, overexpression of Bax/Bcl-2 mRNA ratio as well as caspase-9 and −3. Moreover, it was deduced that IBC mitigated the expression of survivin at mRNA and protein levels. Then, binding parameters indicated that IBC strongly binds to one molecule of survivin at physiological temperature. Also, it was revealed that IBC substantially induced the conformational changes of survivin. Ultimately, through hydrogen bonding and hydrophobic forces, IBC has a substantial binding affinity with survivin (–9.80 kcal/mol) at a region that is critical to the dimerization process, according to molecular docking studies. Overall, this study showed that IBC may be used in future research to assess its clinical and in vivo behaviors in the modulation of colorectal cancer mediated by deactivation and downregulation of antiapoptotic survivin.

Keywords

• Isobavachalcone
• Colorectal cancer
• Survivin
• Apoptosis
• Spectroscopy
• Docking