Gold and Silver Nanoparticles Efficiently Modulate the Crosstalk Between Macrophages and Cancer Cells

Area of Science:

• * Immunology and Nanomedicine: Investigating the interplay between nanoparticles and the immune system within the tumor microenvironment.

Background:

• * Tumor-associated macrophages (TAMs) are crucial in innate immunity and can adopt pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes.
• * Cancer cells manipulate TAMs in the tumor microenvironment, influencing their polarization and function.

Purpose of the Study:

• * To investigate the effects of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) on TAM behavior and polarization.
• * To understand how these nanoparticles modulate the communication between cancer cells and TAMs.

Main Methods:

• * Co-culture of macrophages (J774 or primary bone marrow-derived) with 4T1 breast cancer cells treated with AgNPs or AuNPs.
• * Assessment of macrophage polarization and functional markers via RT-qPCR and Proteome Profiler Array.
• * Evaluation of macrophage migration and matrix metalloproteinase activity.

Main Results:

• * AgNPs and AuNPs shifted TAM polarization towards an M1-like phenotype, decreasing M2 markers.
• * Nanoparticle treatment reduced levels and activity of factors associated with cell migration, including matrix metalloproteinases.
• * Macrophage migration was suppressed in the presence of nanoparticles.

Conclusions:

• * Both AgNPs and AuNPs effectively modulated macrophage-cancer cell communication.
• * These nanoparticles indirectly suppressed M2-like TAM polarization and impaired TAM migration.
• * The findings suggest that AgNPs and AuNPs can debilitate TAMs' cancer-promoting capabilities and modulate their immunological functions.