CD38-Driven Mitochondrial Trafficking Promotes Bioenergetic Plasticity in Multiple Myeloma

Area of Science:

• Cancer Biology
• Cellular Metabolism
• Mitochondrial Dynamics

Background:

• Cancer cells require metabolic adaptations for growth and spread.
• Mitochondria can transfer between cells, but their impact on cancer metabolism is not fully understood.
• Multiple myeloma cells reside in the bone marrow microenvironment.

Purpose of the Study:

• To investigate the metabolic consequences of mitochondrial transfer to multiple myeloma cells.
• To elucidate the mechanism of mitochondrial transfer in the bone marrow microenvironment.
• To explore therapeutic strategies targeting mitochondrial transfer.

Main Methods:

• Investigated metabolic activity (glycolysis and oxidative phosphorylation) in multiple myeloma cells.
• Examined intercellular mitochondrial transfer using tumor-derived tunneling nanotubes (TNTs).
• Utilized shRNA-mediated knockdown of CD38 to inhibit mitochondrial transfer and TNT formation.
• Assessed the effects of CD38 inhibition on tumor progression and survival in vivo.

Main Results:

• Multiple myeloma cells exhibit both glycolysis and mitochondrial oxidative phosphorylation within the bone marrow.
• Intercellular mitochondrial transfer from bone marrow stromal cells to multiple myeloma cells fuels oxidative phosphorylation.
• Mitochondrial transfer occurs via tumor-derived tunneling nanotubes (TNTs).
• CD38 knockdown inhibits mitochondrial transfer and TNT formation in vitro and in vivo, improving animal survival.

Conclusions:

• Multiple myeloma cells adapt their metabolism by acquiring mitochondria from the bone marrow microenvironment.
• Tunneling nanotubes (TNTs) mediate the transfer of mitochondria, enhancing cancer cell metabolism.
• Targeting CD38 to inhibit mitochondrial transfer presents a promising therapeutic avenue for multiple myeloma.