Structural tuning of organoruthenium compounds allows oxidative switch to control ER stress pathways and bypass...

Area of Science:

• Medicinal Chemistry
• Cancer Biology
• Cellular Stress Responses

Background:

• Multidrug resistance (MDR) significantly limits chemotherapy efficacy in cancer treatment.
• A key MDR mechanism involves cancer cells adapting survival pathways to resist apoptosis (programmed cell death).
• Targeting alternative cell death pathways is a promising strategy to overcome MDR.

Purpose of the Study:

• To investigate the potential of two organoruthenium complexes, RAS-1H and RAS-1T, in inducing non-apoptotic cell death.
• To elucidate the distinct mechanisms of action of RAS-1H and RAS-1T in triggering programmed cell death (PCD).
• To evaluate the efficacy of these complexes against apoptosis-resistant cancer cells.

Main Methods:

• Synthesis and characterization of organoruthenium complexes RAS-1H and RAS-1T.
• Assessment of cell death pathways induced by the complexes, focusing on ER stress and reactive oxygen species (ROS).
• Comparative efficacy studies against apoptosis-resistant cancer cells versus clinical drugs like oxaliplatin.

Main Results:

• Both RAS-1H and RAS-1T induced non-apoptotic PCD through endoplasmic reticulum (ER) stress.
• RAS-1T's mechanism involved ROS-mediated ER stress, while RAS-1H acted independently of ROS.
• The organoruthenium complexes demonstrated superior efficacy against apoptosis-resistant cells compared to oxaliplatin.

Conclusions:

• Organoruthenium complexes can effectively induce non-apoptotic PCD via ER stress modulation.
• Distinct structural variations in metal complexes lead to different ROS-dependent or independent ER stress pathways.
• These findings support the development of ER stress-modulating metal complexes as a novel approach to circumvent MDR in cancer therapy.