Dr. Jesse Zaretsky joined the Department of Medicine in the Division of Oncology as an Instructor in August of 2025. His clinical and research interests focus on understanding mechanisms of resistance to immunotherapy to guide better treatments for head and neck squamous cell carcinoma and other cancers. Therapies that activate the immune system to fight cancer are now part of standard treatment for multiple cancer types and can shrink tumors to provide years of disease-free survival. However not all tumors respond to treatment, and some that do eventually recur.
In the laboratory, they use tumor biopsy samples from patients treated with immunotherapy and cutting-edge tools (such as single-cell RNA sequencing and highly multiplexed immunofluorescent staining) to deeply examine the tumor-immune microenvironment and features associated with tumor response and patient outcome. They seek to understand the how tumor cell-intrinsic states, local immune cell populations and activity, and the signaling between them leads to ineffective immune responses despite often abundant T-cell infiltration after continuous checkpoint blockade. They then model these interactions in the lab to understand their regulation and ways to modulate them that might lead to more effective therapies or combinations of therapies for patients. In the clinic, Dr. Zaretsky sees patients with head and neck cancers and prioritizes enrollment in early phase clinical trials with an emphasis on new immunotherapy and combination treatments.