Bacteria-Driven Tumor Microenvironment-Sensitive Nanoparticles Targeting Hypoxic Regions Enhances the Chemotherapy Outcome of Lung Cancer

Background: Chemotherapy still plays a dominant role in cancer treatment. However, the inability of conventional chemotherapeutic drugs to reach the hypoxic zone of solid tumors significantly weakens their efficacy. Bacteria-mediated drug delivery systems can be an effective targeting strategy for improving the therapeutic outcomes in cancer. Anaerobic bacteria have the unique ability to selectively transport drug loads to the hypoxic regions of tumors. Methods: We designed a Bifidobacterium infantis (Bif)-based biohybrid (Bif@PDA-PTX-NPs) to deliver polydopamine (PDA)coated paclitaxel nanoparticles (PTX-NPs) to tumor tissues. Results: The self-driven Bif@PDA-PTX-NPs maintained the toxicity of PTX as well as the hypoxic homing tendency of Bif. Furthermore, Bif@PDA-PTX-NPs significantly inhibited the growth of A549 xenografts in nude mice, and prolonged the survival of the tumor-bearing mice compared to the other PTX formulations without any systemic or localized toxicity. Conclusion: The Bif@PDA-PTX-NPs biohybrids provide a new therapeutic strategy for targeted chemotherapy to solid tumors.

Automated summary

A new Bifidobacterium infantis (Bif)-based biohybrid (Bif@PDA-PTX-NPs) was designed to deliver polydopamine (PDA)-coated paclitaxel nanoparticles (PTX-NPs) to tumor tissues. Bif@PDA-PTX-NPs maintained the toxicity of PTX and the hypoxic homing tendency of Bif, significantly inhibiting the growth of A549 xenografts in nude mice and prolonging the survival of tumor-bearing mice.