HDAC6 orchestrates NK cell maturation and antitumor immunity

Area of Science:

• Immunology
• Cell Biology
• Cancer Research

Background:

• Natural killer (NK) cells are crucial for immunosurveillance but their regulation is complex.
• Histone deacetylase (HDAC) inhibition affects NK cell function, yet the specific HDAC and mechanisms are unknown.

Purpose of the Study:

• To investigate the role of specific HDAC members in NK cell biology.
• To elucidate the mechanisms by which HDACs regulate NK cell maturation and effector functions.

Main Methods:

• Analyzed HDAC family expression in activated and tumor-infiltrating NK cells.
• Utilized genetic manipulation (knockout, knockdown, overexpression) of HDAC6.
• Examined protein acetylation, HSP90 chaperone activity, and IL-15/STAT5 signaling.
• Assessed functional impact using adoptive transfer and combination treatments in tumor models.

Main Results:

• HDAC6 expression increased upon NK cell activation but decreased in tumor-infiltrating cells, correlating with poor survival.
• HDAC6 deficiency impaired NK cell proliferation, maturation, and function; overexpression promoted these.
• HDAC6 loss caused HSP90 hyperacetylation, disrupting STAT5 phosphorylation and IL-15 signaling.
• HDAC6 overexpression enhanced NK cell-mediated tumor suppression and synergized with IL-15 therapy.

Conclusions:

• HDAC6 is a key regulator of NK cell biology, primarily by reinforcing the IL-15/STAT5 pathway.
• HDAC6 represents a potential therapeutic target for enhancing NK cell-based immunotherapy.