Tucatinib promotes immune activation and synergizes with programmed cell death-1 and programmed cell death-ligand 1 inhibition in HER2-positive breast cancer
Details
Publication Year 2023-07-06,Volume 115,Issue #7,Page 805-814
Journal Title
Journal of the National Cancer Institute
Publication Type
Research article
Abstract
BACKGROUND: Programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) inhibitors have poor efficacy in patients with trastuzumab-resistant advanced HER2-positive breast cancer. Tucatinib is a potent, selective anti-HER2 tyrosine kinase inhibitor with proven clinical benefit in the advanced setting in patients with trastuzumab resistance. We investigated if tucatinib can alter the tumor microenvironment and if this could be harnessed for therapeutic efficacy. METHODS: We investigated the antitumor efficacy and contribution of the immune response of tucatinib using 2 immunocompetent, HER2-positive murine breast cancer models (trastuzumab-sensitive H2N113; trastuzumab-resistant Fo5) and the efficacy of tucatinib with trastuzumab and PD-1 or PD-L1 checkpoint inhibitors. RESULTS: In both models, tucatinib statistically significantly inhibited tumor growth and demonstrated dose-dependent efficacy. Ex vivo analysis by flow cytometry of tumor-infiltrating lymphocytes in mice treated with tucatinib showed increased frequency, higher proliferation, and enhanced effector function of CD8+ effector memory T cells. Tucatinib treatment also increased frequency of CD8+PD-1+ and CD8+TIM3+ T cells, CD49+ natural killer cells, monocytes, and major histocompatibility complex II expression on dendritic cells and macrophages and a decrease in myeloid-derived suppressor cells. Gene expression analysis revealed statistically significant enrichment in pathways associated with immune activation, type I and II interferon response, adaptive immune response, and antigen receptor signaling. In vivo, tucatinib and alpha-PD-L1 or alpha-PD-1 demonstrated statistically significantly increased efficacy and improved survival of mice compared with tucatinib alone. CONCLUSION: Tucatinib modulates the immune microenvironment favorably, and combination treatment with alpha-PD-L1 or alpha-PD-1 demonstrated increased efficacy in preclinical HER2-positive tumor models. These findings provide a rationale for investigation of tucatinib and immune checkpoint inhibition in the clinic.
Publisher
Oxford University Press
Keywords
Mice; Humans; Animals; Female; *B7-H1 Antigen; Receptor, ErbB-2/metabolism; Programmed Cell Death 1 Receptor; Ligands; *Breast Neoplasms/pathology; Trastuzumab/therapeutic use; CD8-Positive T-Lymphocytes; Apoptosis; Tumor Microenvironment
Department(s)
Laboratory Research; Medical Oncology; Surgical Oncology
PubMed ID
37166471
Terms of Use/Rights Notice
Refer to copyright notice on published article.


Creation Date: 2023-10-24 12:16:58
Last Modified: 2024-07-09 06:25:32

© 2024 The Walter and Eliza Hall Institute of Medical Research. Access to this website is subject to our Privacy Policy and Terms of Use

An error has occurred. This application may no longer respond until reloaded. Reload 🗙