Sonogenetics-controlled synthetic designer cells for cancer therapy in tumor mouse models

Abstract

Bacteria-based therapies are powerful strategies for cancer therapy, yet their clinical application is limited by a lack of tunable genetic switches to safely regulate the local expression and release of therapeutic cargoes. Rapid advances in remote-control technologies have enabled precise control of biological processes in time and space. We developed therapeutically active engineered bacteria mediated by a sono-activatable integrated gene circuit based on the thermosensitive transcriptional repressor TlpA₃₉. Through promoter engineering and ribosome binding site screening, we achieved ultrasound (US)-induced protein expression and secretion in engineered bacteria with minimal noise and high induction efficiency. Specifically, delivered either intratumorally or intravenously, engineered bacteria colonizing tumors suppressed tumor growth through US-irradiation-induced release of the apoptotic protein azurin and an immune checkpoint inhibitor, a nanobody targeting programmed death-ligand 1, in different tumor mouse models. Beyond developing safe and high-performance designer bacteria for tumor therapy, our study illustrates a sonogenetics-controlled therapeutic platform that can be harnessed for bacteria-based precision medicine.

Keywords: PD-L1 nb; TlpA39; VNP20009; azurin; bacteria-based therapy; cancer therapy; sonogenetics; synthetic designer cells; synthetic gene circuit; ultrasound.