Low-Dose Eribulin Promotes NK Cell-Mediated Therapeutic Efficacy in Bladder Cancer

Area of Science:

• Immunology
• Oncology
• Pharmacology

Background:

• Bladder cancer (BCa) exhibits suboptimal responses to current immunotherapies.
• Natural killer (NK) cells are crucial for patient survival in BCa.
• Eribulin, a microtubule destabilizer, is being investigated for BCa treatment, but its mechanism is unclear.

Purpose of the Study:

• To investigate the effects of low-dose eribulin on NK cell activation in BCa.
• To elucidate the mechanism by which eribulin enhances NK cell-mediated anti-tumor activity.

Main Methods:

• In vitro studies using primary patient samples and in vivo murine models.
• Flow cytometry and RNA sequencing to analyze NK cell activation and function.
• Assessment of eribulin's impact on NK cell migration, cytotoxicity, and subset distribution.

Main Results:

• Low-dose eribulin instillation reduced bladder tumor burden and improved survival in an NK cell-dependent manner.
• Eribulin promoted a shift towards anti-tumor CD49a+ CD103+ NK cells (ILC1-like) and reduced dysfunctional NR4A2+ NK cells.
• Eribulin decreased NK cell exhaustion markers in both patient samples and murine models.

Conclusions:

• Low-dose eribulin chemotherapy demonstrates a novel immunomodulatory effect in BCa.
• Eribulin enhances anti-tumor NK cell immunity, contradicting the traditional view of chemotherapy as immunosuppressive.
• These findings support new therapeutic strategies combining eribulin with immunotherapy for improved BCa treatment.