IRE-1-Targeting Caged Prodrug with Endoplasmic Reticulum Stress-Inducing and XBP-1S-Inhibiting Activities for Cancer...

Area of Science:

• Biochemistry
• Molecular Biology
• Cancer Research

Background:

• The IRE-1/XBP-1s pathway is crucial for tumor progression.
• Targeting this pathway offers a potential strategy for cancer therapy.

Purpose of the Study:

• To develop and characterize a novel prodrug, TC-D-F07, for targeted inhibition of the IRE-1/XBP-1s pathway.
• To investigate the stimulus-mediated release and efficacy of TC-D-F07 in cancer cells.

Main Methods:

• Synthesis of TC-D-F07, a prodrug of the IRE-1 inhibitor D-F07, featuring a thiol-reactive dinitrobenzenesulfonyl (Dns) cage.
• Evaluation of TC-D-F07 sensitivity to intracellular thiols (glutathione, cysteine).
• Assessment of D-F07 release kinetics and endoplasmic reticulum (ER) stress induction in tumor versus normal cells.
• Comparison of apoptosis induction by TC-D-F07 and its uncaged analogue.

Main Results:

• TC-D-F07 demonstrates stimulus-mediated control of inhibitory activity, releasing D-F07 upon exposure to intracellular thiols.
• Higher concentrations of thiols in tumor cells lead to more sustained D-F07 levels compared to normal cells.
• Cleavage of the Dns group induces ER stress and increases XBP-1s expression, followed by sustained D-F07 inhibition, leading to enhanced apoptosis in tumor cells.

Conclusions:

• TC-D-F07 provides a targeted approach to inhibit the IRE-1/XBP-1s pathway in cancer.
• The prodrug design enables selective drug release and enhanced therapeutic efficacy in tumor cells.
• TC-D-F07 demonstrates potential as a novel therapeutic agent for cancers dependent on the IRE-1/XBP-1s pathway.