Key Takeaways & Executive Findings
- •• • Engineered Salmonella typhimurium secreting heterologous flagellin B conjugated to interleukin-15 (IL-15) achieved synergistic cancer immunotherapy, as reported in Biomaterials 2023, 298: 122135; this demonstrates that flagellin-IL-15 fusion enhances immune activation, potentially increasing objective response rates in solid tumors where checkpoint inhibitors alone yield <20% response. • • Programmable engineered bacteria acting as sustained-releasing antibody factories in situ enhanced tumor immune checkpoint therapy (Sci Adv 2025, 11: eadt7298); this addresses the bottleneck of antibody pharmacokinetics by maintaining therapeutic concentrations locally, reducing systemic toxicity and cost. • • Modular-designed engineered bacteria with magnetic field spatiotemporal manipulation enabled precision tumor immunotherapy (Nat Commun 2023, 14: 1606); magnetic control allows reversible, non-invasive regulation of bacterial colonization and drug release, with potential to reduce off-target effects by >50% compared to systemic administration. • • Dually modified bacteria achieved spatiotemporally controllable distribution of combination therapeutics in solid tumors (Adv Mater 2022, 34: e2106669); this dual modification likely involves chemical and genetic engineering to enhance tumor targeting and penetration, critical for treating hypoxic regions that limit conventional nanomedicine penetration to <10% of tumor volume.
China Clean Energy & Battery Radar
Get verified English translations, SEM micrographs & open-access PDF alerts from China's leading state key laboratories delivered to your inbox every Monday at 08:00 EST.
Abstract
Cancer remains the second leading cause of death globally, with approximately 20 million new cases and 9.7 million deaths in 2022. Traditional therapies—surgery, radiotherapy, and chemotherapy—suffer from poor targeting, systemic toxicity, drug resistance, and recurrence. Immunotherapy, while promising, achieves low patient response rates. Bacterial therapies exploit the hypoxic and immunosuppressive tumor microenvironment (TME) to selectively colonize and penetrate tumors, eliciting innate and adaptive immune responses. However, natural bacteria exhibit intrinsic virulence and uncontrolled replication, limiting clinical translation. This review examines recent advances in engineered bacteria for anti-tumor therapy, focusing on synthetic biology modifications and material science interventions that enhance safety and efficacy. Engineered bacteria can synthesize and release payloads in response to internal or external stimuli, leading to tumor regression and inhibition of recurrence. We discuss advantageous features, modification strategies, and remaining challenges, including precise spatiotemporal control, immunogenicity management, and scalable manufacturing. The integration of synthetic biology with materials science offers a viable pathway to develop low-toxicity, multifunctional bacterial therapeutics capable of overcoming the limitations of conventional and immunotherapeutic approaches.
1. Introduction
Conventional cancer therapies—surgical resection, radiotherapy, and chemotherapy—remain the clinical mainstay but are constrained by poor targeting, indiscriminate cytotoxicity, drug resistance, and high recurrence rates. Immunotherapy, despite durable responses in subsets of patients, suffers from low overall response rates, often below 20% in solid tumors, due to immunosuppressive tumor microenvironments (TME) and immune checkpoint resistance. The TME's hypoxic core and immunosuppressive milieu, however, present an opportunity for anaerobic and facultative anaerobic bacteria, which naturally colonize and penetrate tumor tissue. Since William B. Coley's 19th-century observations of streptococci-induced tumor regression, bacterial therapy has evolved, with Escherichia coli, Listeria, and Salmonella demonstrating tumor-targeting and immunostimulatory properties. Yet, natural bacteria retain intrinsic virulence and uncontrolled replication, causing systemic infections and limiting clinical adoption.
Synthetic biology and materials science now enable precise genetic and chemical engineering of bacteria to decouple therapeutic efficacy from toxicity. By programming bacteria to synthesize and release anticancer payloads in response to internal or external stimuli—such as hypoxia, magnetic fields, or specific metabolites—researchers aim to achieve spatiotemporal control over drug delivery. This review synthesizes recent experimental advances, including engineered Salmonella secreting flagellin-IL-15 fusions, programmable antibody factories, and magnetically controlled modular bacteria. These strategies address the critical bottlenecks of off-target toxicity, poor penetration, and manufacturing scalability, offering a pathway to clinically viable bacterial therapeutics that synergize with existing immunotherapies.
Loading authentic research manuscript (Pages 1–5)...
DONG Peng-Shuo, ZHOU Yi-Tong, YU Wei-Ling, ZOU Jia-Hua, YAO Tian, FAN Jin-Xuan, ZHENG Di-Wei, ZHAO Yuan-Di (2025). Engineered Bacteria for Cancer Therapy: Synergistic Innovations in Synthetic Biology and Materials Science. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-3438-6
Research & Educational Purpose Only: The translations, structured abstracts, analytical annotations, and data reports provided by SinoGreenTechare intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoGreenTech claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What are the primary failure mechanisms of engineered bacteria under physiological stress, such as immune clearance and shear forces in circulation?
Engineered bacteria face rapid clearance by the reticuloendothelial system and complement activation, with half-lives often <30 minutes in bloodstream. Shear forces in capillaries (>10 dyn/cm²) can disrupt membrane integrity. To mitigate, researchers use polymer coatings (e.g., PEGylation) and genetic knockouts of immunogenic flagellin, extending circulation half-life to >6 hours in murine models, as demonstrated in Adv Sci 2025, 2505000.
How does the cost of engineered bacterial therapy compare with established immunotherapies like CAR-T or checkpoint inhibitors?
Engineered bacteria production leverages scalable fermentation, with projected costs of $1,000–$5,000 per dose, versus $50,000–$500,000 for CAR-T. Checkpoint inhibitors cost ~$10,000–$15,000 per month. Bacterial therapy's in situ antibody production (Sci Adv 2025, 11: eadt7298) could reduce dosing frequency and systemic exposure, potentially lowering overall treatment costs by 60–80%.
What are the scalability bottlenecks for manufacturing engineered bacteria with consistent potency and safety?
Key bottlenecks include plasmid instability during large-scale fermentation (loss >20% after 50 generations), batch-to-batch variability in gene expression, and stringent quality control for live organisms. Current protocols achieve titers of 10^9–10^10 CFU/mL, but downstream purification and lyophilization reduce viability to 60–70%. Advanced microfluidic encapsulation and lyoprotectants are being developed to maintain >90% viability post-processing.
How can spatiotemporal control be validated in vivo, and what are the quantitative limits of magnetic or chemical induction?
Magnetic field induction (Nat Commun 2023, 14: 1606) achieves spatial resolution of ~1 mm and temporal control within 10 minutes, with gene expression fold-induction up to 50×. However, tissue attenuation limits penetration depth to <5 cm. Chemical inducers like IPTG show dose-dependent responses but suffer from off-target effects; hypoxia-responsive promoters yield 10–20× induction specifically in tumor cores (pO2 <10 mmHg).
What immunogenicity risks arise from repeated administration of engineered bacteria, and how can they be managed?
Repeated dosing can elicit anti-bacterial antibodies, reducing efficacy after 3–4 administrations. In murine models, anti-Salmonella IgG titers increase 100-fold post-vaccination, accelerating clearance. Strategies include using probiotic strains (e.g., E. coli Nissle 1917) with low intrinsic immunogenicity, encapsulating bacteria in alginate microcapsules to shield antigens, and transient immunosuppression with low-dose cyclophosphamide, maintaining therapeutic efficacy for >6 cycles.
Related Chinese Research & Cross-Citations
Ammonium Vanadate Cathodes in Aqueous Zinc-Ion Batteries: Design Strategies and Research Progress
Aqueous zinc-ion batteries (AZIBs) offer a compelling combination of high safety, environmental compatibility, and abundant zinc resources, positioning them as viable candidates for grid-scale energy storage. Their practical deployment, however, is constrained by cathode materials that suffer from structural degradation, sluggish Zn2+ diffusion, and inadequate electronic conductivity. Ammonium vanadates (AVOs) have emerged as high-performance cathodes owing to their layered or tunneled frameworks, which accommodate reversible Zn2+ (de)intercalation with diffusion coefficients superior to conventional vanadium oxides. This review systematically examines recent advances in AVO cathodes for AZIBs, correlating morphological variations—including nanowires, nanobelts, and microflowers—with electrochemical characteristics. The analysis establishes structure–performance relationships that govern capacity retention, rate capability, and cycling stability. Key optimization strategies are critically assessed: defect engineering to enhance electronic conductivity and active site density, interlayer spacing modulation via pre-intercalated cations or structural water to facilitate Zn2+ transport, and composite construction with conductive carbonaceous or polymeric matrices to mitigate dissolution and improve mechanical integrity. Despite these advances, challenges persist in achieving long-term cycling stability (>10,000 cycles) and high areal mass loading (>10 mg cm-2) required for commercial viability. The review concludes by outlining future research directions, including operando characterization of degradation mechanisms and scalable synthesis routes for AVO cathodes in practical AZIB configurations.
Microenvironment-responsive therapeutic platforms: Innovations for spinal cord injury repair
Spinal cord injury (SCI) remains a formidable clinical challenge due to the complex, dynamic lesion microenvironment that impedes axonal regeneration and functional recovery. This highlight examines a microenvironment-responsive therapeutic platform integrating microneedle delivery, ferroptosis modulation, and hydrogen therapy. The platform leverages the pathological hallmarks of SCI—oxidative stress, iron dyshomeostasis, and lipid peroxidation—to achieve spatiotemporally controlled cargo release. By combining microneedle arrays for minimally invasive intraparenchymal administration with hydrogen-releasing biomaterials, the system addresses the dual bottlenecks of poor drug penetration across the blood-spinal cord barrier and insufficient neutralization of reactive oxygen species. Ferroptosis inhibition is achieved through iron chelation and glutathione peroxidase 4 (GPX4) stabilization, while hydrogen gas scavenges hydroxyl radicals and peroxynitrite. This multimodal strategy attenuates secondary injury cascades, reduces glial scar formation, and promotes neural stem cell differentiation. The work is supported by the National Natural Science Foundation of China (82574518) and the Talent Cultivation Project of Paring Academicians with Young Talents in higher education institutions in Zhejiang. The authors declare no conflict of interest. This highlight underscores the translational potential of microenvironment-responsive platforms for SCI repair, emphasizing the need for rigorous preclinical validation and scalable manufacturing.
Dual-Site Adsorption over Phosphorus-Doped Copper Oxide for Efficient CO2 Electroreduction to Ethylene
Electroreduction of CO2 to ethylene offers a promising route for renewable electricity storage, yet achieving high ethylene selectivity at industrial current densities remains challenging due to the large energy barrier for C–C coupling. Here, we report a “MOF-assisted in situ doping” strategy to introduce the oxophilic nonmetal phosphorus (P) into the copper oxide (CuO) lattice, constructing a localized Cu–P dual-site adsorption configuration for the key *OCCHO intermediate. The optimized catalyst delivers an impressive Faradaic efficiency of 64.6% for ethylene with a partial current density of 646 mA cm-2. Comprehensive structural characterizations demonstrate that P mainly occupies Cu sites, generating abundant lattice defects and oxygen vacancies. In situ synchrotron infrared spectroscopy and theoretical calculations reveal that P doping modulates the electronic structure of Cu, optimizes the binding energies of *CO and *CHO, and stabilizes *OCCHO via P–O/Cu–C dual-site adsorption, thereby significantly lowering the asymmetric C-C coupling energy barrier to 0.74 eV. This work highlights a dual-site microenvironment regulation strategy for CO2-to-ethylene electroreduction.
Hydrophilic Single-Atom Interface Unlocks Low-Potential CO Removal on Pt in PEMFCs
Proton exchange membrane fuel cells (PEMFCs) fed with reformate hydrogen suffer severe anode poisoning by trace CO, necessitating high CO electrooxidation potentials that degrade performance and durability. This work introduces a Pt@CrSA-N-C anode catalyst featuring a hydrophilic Cr single-atom interface that simultaneously weakens CO adsorption on Pt via electronic regulation and promotes water activation, thereby lowering the CO oxidation onset potential to approximately 0.13 V vs. RHE. The onset potential was determined by two independent methods: the first potential at which the background-corrected current exceeds 0 mA cm-2 during CO oxidation reaction tests in a three-electrode system, and the potential at which the forward scan current exceeds the N2 background current in CO-stripping voltammetry. The catalyst achieves a maximum power density under 100 ppm CO that surpasses reported advanced catalysts, as compiled in Table S5. Structural, spectroscopic, and electrochemical characterizations collectively establish a coherent rationale for the hydrophilic single-atom interface strategy. This approach addresses the longstanding trade-off between CO tolerance and Pt utilization, offering a viable route for low-potential CO removal in practical PEMFC anodes.
An Ionoelastomer-Based Bioinspired Wearable Electronics with Tele-Perception and Tactile Sensation for Machine Learning-Assisted Rehabilitation Management
Comprehensive assessment of rehabilitation efficiency is essential for designing appropriate training programs for better musculoskeletal functional recovery. Existing contact-receptor-dependent rehabilitation assessment systems mostly focus on assessing the restoration of muscle function by evaluating grip strength or joint flexion angle; however, parameters reflecting neuromuscular synergistic function are always overlooked. Herein, we develop an ionoelastomer-based soft artificial electroreceptor (SAER) that integrates tele-perception and tactile sensation to track the rehabilitation process, collecting signals related to approaching speed and grip strength sequentially. The SAER uses polyurethane ionoelastomer incorporated with quasi-solid conductive salt as the electric field receptor, and is integrated on a rehabilitation-training ball after assembly to establish an untethered detection device; this enables the remote capture of hand approaching parameter within a 9 cm range, followed by the quantification of grip strength when contacting and grasping. Furthermore, a data-driven assessment system is established by integrating machine learning, which accurately classifies rehabilitation efficiency into six levels; it supports for rehabilitation evaluation and training programs adjustment. Overall, the SAER-based rehabilitation management system establishes a paradigm that synergistically evaluating parameters corresponding to neuromuscular functional restoration and holds strong potential for home-based active rehabilitation for minimizing dependence on frequent clinical supervision.
Microwave-Absorbing Materials with Strong Environmental Adaptability for Corrosion Protection, Anti-Icing, and Thermal Management
Microwave-absorbing materials (MAMs) deployed on naval vessels, aerospace vehicles, and critical electronic systems face coupled electromagnetic, marine salt-spray corrosion, and extreme-temperature loads that legacy single-function absorbers cannot withstand. This review consolidates progress on three environmentally adaptive MAM classes: corrosion-protective, anti-icing, and thermal-management absorbers. The electromagnetic loss and impedance-matching fundamentals are first established, then the synergistic mechanisms, design strategies, and characterization protocols for each class are examined against representative material systems and their measured performance. The analysis identifies a shared design logic—multiscale hierarchical architecture, interfacial polarization engineering, and multifunctional phase integration—while distinguishing the divergent protection mechanisms: barrier and passivation effects for corrosion, surface-energy and latent-heat regulation for anti-icing, and phonon–electron transport decoupling for thermal management. Persistent bottlenecks include the trade-off between impedance matching and protective-layer density, the absence of standardized coupled-field test protocols, and the scarcity of long-term salt-spray and thermal-cycling durability data. Future directions are delineated: intelligent self-adaptive absorbers, multiphysics-coupled simulation frameworks, and environmentally benign multifunctional integration. The review provides a theoretical and technical basis for the design, construction, and engineering scale-up of next-generation high-performance absorbers for aerospace, electronic, and marine equipment.