Human prostate cancer bone metastases have an actionable immunosuppressive microenvironment

Menée à l'aide d'échantillons de moelle osseuse d'origine humaine, d'échantillons tumoraux et d'un modèle murin, cette étude démontre que les métastases osseuses des cancers humains de la prostate ont un micro-environnement immunosuppresseur qui peut être modifié en ciblant l'axe "ligand CCL20 - récepteur CCR6"

Résumé en anglais

Bone metastases are devastating complications of cancer. They are particularly common in prostate cancer (PCa), represent incurable disease, and are refractory to immunotherapy. We seek to define distinct features of the bone marrow (BM) microenvironment by analyzing single cells from bone metastatic prostate tumors, involved BM, uninvolved BM, and BM from cancer-free, orthopedic patients, and healthy individuals. Metastatic PCa is associated with multifaceted immune distortion, specifically exhaustion of distinct T cell subsets, appearance of macrophages with states specific to PCa bone metastases. The chemokine CCL20 is notably overexpressed by myeloid cells, as is its cognate CCR6 receptor on T cells. Disruption of the CCL20-CCR6 axis in mice with syngeneic PCa bone metastases restores T cell reactivity and significantly prolongs animal survival. Comparative high-resolution analysis of PCa bone metastases shows a targeted approach for relieving local immunosuppression for therapeutic effect.