Genetically Engineered Probiotic Nanoplatform for Ultrasound-Enhanced Colorectal Cancer Therapy via Targeted Delivery, Immune Modulation, and Anti-Angiogenesis.

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality worldwide, largely due to limitations in early diagnosis and effective treatment. To address these challenges, we developed a multifunctional probiotic nanoplatform, EcNA@Cur-Lip-FA, that integrates real-time diagnosis, targeted therapy, and immune modulation for enhanced CRC treatment. Specifically, this system leverages genetically engineered Escherichia coli Nissle 1917 (EcN) encoding acoustic reporter genes (ARGs) to produce ultrasound (US)-responsive gas vesicles (GVs), enabling real-time, noninvasive tumor imaging. Simultaneously, folic acid (FA)-modified curcumin-loaded liposomes (Cur-Lip-FA) are co-delivered with EcN, enhancing tumor-specific accumulation and therapeutic precision.

After being taken up by tumor cells, curcumin is released locally upon exposure to US irradiation, generating reactive oxygen species (ROS), inducing immunogenic cell death (ICD), and activating the cGAS-STING pathway to promote dendritic cells (DCs) maturation and robust CD4+/CD8+ T-cell responses.

Additionally, EcNA@Cur-Lip-FA downregulates angiogenesis-related factors (VEGF, VEGFR1, and ANGPT1), thereby inhibiting tumor neovascularization. In vitro and in vivo studies demonstrated that EcNA@Cur-Lip-FA enables precise tumor localization, dynamic imaging, and effective suppression of both primary CRC and metastatic liver lesions with favorable biocompatibility. This multifunctional platform offers a promising strategy for integrating diagnosis and treatment, paving the way for next-generation CRC theranostics.