Macrophages directly kill bladder cancer cells through TNF signaling as an early response to BCG therapy.

ABSTRACT: The Bacillus Calmette-Guérin (BCG) vaccine is the oldest cancer immunotherapeutic agent in use. Despite its effectiveness, its initial mechanisms of action remain largely unknown. Here, we elucidate the earliest cellular mechanisms involved in BCG-induced tumor clearance. We developed a fast preclinical in vivo assay to visualize in real time and at single-cell resolution the initial interactions among bladder cancer cells, BCG and innate immunity using the zebrafish xenograft model. We show that BCG induced the recruitment and polarization of macrophages towards a pro-inflammatory phenotype, accompanied by induction of the inflammatory cytokines tnfa, il1b and il6 in the tumor microenvironment. Macrophages directly induced apoptosis of human cancer cells through zebrafish TNF signaling. M

SUBMITTER: Martinez-Lopez MF 

PROVIDER: S-EPMC11554267 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature