Journal Article

Ancient drug curcumin impedes 26S proteasome activity by direct inhibition of dual-specificity tyrosine-regulated kinase 2

Dixon, Jack E., Banerjee, Sourav, Ji, Chenggong, Guo, Xing, Mayfield, Joshua E., Xiao, Junyu, Goel, Apollina

2018

Overview

Curcumin, the active ingredient in Curcuma longa, has been in medicinal use since ancient times. However, the therapeutic targets and signaling cascades modulated by curcumin have been enigmatic despite extensive research. Here we identify dual-specificity tyrosine-regulated kinase 2 (DYRK2), a positive regulator of the 26S proteasome, as a direct target of curcumin. Curcumin occupies the ATP-binding pocket of DYRK2 in the cocrystal structure, and it potently and specifically inhibits DYRK2 over 139 other kinases tested in vitro. As a result, curcumin diminishes DYRK2-mediated 26S proteasome phosphorylation in cells, leading to reduced proteasome activity and impaired cell proliferation. Interestingly, curcumin synergizes with the therapeutic proteasome inhibitor carfilzomib to induce apoptosis in a variety of proteasome-addicted cancer cells, while this drug combination exhibits modest to no cytotoxicity to noncancerous cells. In a breast cancer xenograft model, curcumin treatment significantly reduces tumor burden in immunocompromised mice, showing a similar antitumor effect as CRISPR/Cas9-mediated DYRK2 depletion. These results reveal an unexpected role of curcumin in DYRK2-proteasome inhibition and provide a proof-of-concept that pharmacological manipulation of proteasome regulators may offer new opportunities for anticancer treatment.

• Publisher: National Academy of Sciences
• Subject: Animals / Anticancer properties / Antineoplastic Agents - pharmacology / Antineoplastic Agents - therapeutic use / Antitumor activity / Apoptosis / Apoptosis - drug effects / Biochemistry / Biological Sciences / Breast cancer / Cancer / Cascades / Cell growth / Cell proliferation / Cell Proliferation - drug effects / CRISPR / CRISPR-Cas Systems / Crystallography, X-Ray / Curcumin / Curcumin - pharmacology / Curcumin - therapeutic use / Cytotoxicity / Drug Synergism / Dyrk Kinases / Female / Gene Editing - methods / Gene Knockout Techniques - methods / Gene therapy / HEK293 Cells / Humans / Inhibitory Concentration 50 / Kinases / Mice / Neoplasms - drug therapy / Neoplasms - pathology / Oligopeptides - pharmacology / Pharmacology / Phosphorylation / Proteasome 26S / Proteasome Endopeptidase Complex - metabolism / Proteasome inhibitors / Proteasome Inhibitors - pharmacology / Protein Serine-Threonine Kinases - antagonists & inhibitors / Protein Serine-Threonine Kinases - chemistry / Protein Serine-Threonine Kinases - genetics / Protein Serine-Threonine Kinases - metabolism / Protein-Tyrosine Kinases - antagonists & inhibitors / Protein-Tyrosine Kinases - chemistry / Protein-Tyrosine Kinases - genetics / Protein-Tyrosine Kinases - metabolism / Proteins / Regulators / Signal Transduction - drug effects / Therapeutic applications / Toxicity / Tumor Burden - drug effects / Tyrosine / Xenograft Model Antitumor Assays / Xenografts / Xenotransplantation