Language

English

Publication Date

3-6-2025

Journal

Blood

DOI

10.1182/blood.2024026781

PMID

39576960

Abstract

Myeloid differentiation primary response protein 88 (MYD88) is a key adaptor molecule in the signaling pathways of toll-like receptor and interleukin-1 receptor. A somatic mutation resulting in a leucine-to-proline change at position 265 of the MYD88 protein (MYD88 L265P) is one of the most prevalent oncogenic mutations found in patients with hematological malignancies. In this study, we used high-throughput screening to identify lasalocid A as a potent small molecule that selectively inhibited the viability of lymphoma cells expressing MYD88 L265P and the associated activation of NF-κB. Further investigations using CRISPR-CRISPR-associated protein 9 genetic screening, proteomics, and biochemical assays revealed that lasalocid A directly binds to the MYD88 L265P protein, enhancing its interaction with the ubiquitin ligase RNF5. This interaction promotes MYD88 degradation through the ubiquitin-dependent proteasomal pathway, specifically in lymphomas with the MYD88 L265P mutation. Lasalocid A exhibited strong antitumor efficacy in xenograft mouse models, induced disease remission in ibrutinib-resistant lymphomas, and showed synergistic activity with the B-cell lymphoma 2 inhibitor venetoclax. This study highlights the potential of inducing MYD88 L265P degradation using small molecules, offering promising strategies for treating lymphomas that harbor the MYD88 L265P mutation.

Keywords

Myeloid Differentiation Factor 88, Humans, Animals, Mice, Lymphoma, Proteolysis, Xenograft Model Antitumor Assays, Mutation, Cell Line, Tumor, Antineoplastic Agents, Sulfonamides, Mutation, Missense

Published Open-Access

yes

m_blood_bld-2024-026781-ga1.jpeg (63 kB)
Visual Abstract

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.