Synthetic Benzylic Diselenides and Disulfides: Potential Anticancer Activities via Modulation of the ROS-Dependent Akt/β-Catenin Signaling Pathway.

The natural and synthetic organodiselenides have garnered much research attention due to their chemotherapeutic and chemopreventive activities. Herein, we describe the synthesis of a series of benzylic diselenides, which were synthesized by coupling the in situ generated disodium diselenide with the corresponding benzylic halides. The diselenides were evaluated for their anticancer activities in the highly aggressive triple-negative breast cancer cells. Preliminary anti-proliferative activities indicated 4-cyano-substituted diselenide 7 to be most potent with an IC value of 1.9±0.3 μM. Detailed mechanistic investigations showed that diselenide 7 induces apoptosis and causes G1 phase arrest of the cell cycle. It exhibits anticancer activity by suppressing the Akt/β-catenin signaling pathway. Further control experiments with LiCl (inhibitor of GSK-3β) revealed that down-regulation of β-catenin was promoted by GSK-3β-induced phosphorylation of β-catenin and its subsequent proteasomal degradation. Moreover, the intracellular ROS was found to act as an upstream mediator for the inactivation of the Akt/β-catenin signaling pathway. The present study describing the efficient anticancer activity of a synthetic benzylic diselenide towards triple-negative breast cancer cells through the modulation of ROS-dependent Akt/β-catenin signaling pathway would certainly be helpful in the future towards the development of small-molecule organoselenium compounds for the treatment of cancer.