Engineered bacteria for near-infrared light-inducible expression of cancer therapeutics

Abstract

Bacteria-based therapies hold great promise for cancer treatment due to their selective tumor colonization and proliferation. However, clinical application is hindered by the need for safe, precise control systems to regulate local therapeutic payload expression and release. Here we developed a near-infrared (NIR) light-mediated PadC-based photoswitch (NETMAP) system based on a chimeric phytochrome-activated diguanylyl cyclase (PadC) and a cyclic diguanylate monophosphate-dependent transcriptional activator (MrkH). The NETMAP-engineered bacteria exhibited antitumor performance in mouse tumor models with different levels of immunogenicity. Specifically, in immunogenic lymphoma tumors, NIR-induced PD-L1 and CTLA-4 nanobodies enhanced the activation of adaptive immunity. In low-immunogenic tumors—including mouse-derived colon cancer models, an orthotopic human breast cancer cell line-derived xenograft model and a colorectal cancer patient-derived xenograft model—NIR-induced azurin and cytolysin A predominantly led to tumor inhibition. Our study identifies an NIR light-mediated therapeutic platform for engineered bacteria-based therapies with customizable outputs and precise dosage control. Qiao et al. report the design and characterization of an optogenetic platform for the dynamic control of protein expression and secretion by engineered bacteria, with implications for cancer therapy.