Exosomes mediate intercellular transfer of non-autonomous tolerance to proteasome inhibitors in mixed-lineage...

Area of Science:

• Oncology
• Cell Biology
• Molecular Medicine

Background:

• Proteasome inhibitors are crucial in cancer therapy but often lead to drug resistance and disease relapse.
• Existing knowledge on proteasome inhibitor resistance primarily focuses on cell-intrinsic factors, leaving non-autonomous mechanisms unexplored.

Purpose of the Study:

• To investigate the role of non-autonomous mechanisms in the development of proteasome inhibitor resistance.
• To explore exosome-mediated intercellular communication as a driver of proteasome inhibitor tolerance.

Main Methods:

• Utilized mixed-lineage leukemia cells under proteasome inhibitor stress.
• Employed exosome isolation and co-culture experiments to assess intercellular transmission of resistance.
• Performed integrated multi-omics analysis with the Tied Diffusion through Interacting Events algorithm.

Main Results:

• Demonstrated that proteasome inhibitor tolerance can be transmitted non-autonomously via exosomes.
• Exosomes induced cell cycle arrest and enhanced stemness in sensitive cells, conferring reversible resistance.
• Identified candidate exosomal proteins as potential biomarkers and therapeutic targets for refractory mixed-lineage leukemia.

Conclusions:

• Exosome-mediated intercellular transfer plays a significant role in acquired proteasome inhibitor resistance.
• Inhibiting exosome secretion is a viable strategy to reverse drug resistance in vivo.
• This study provides a novel therapeutic approach for refractory and relapsed cancers.