Gelatinase-responsive biodegradable targeted microneedle patch for abscess wound treatment of S. aureus infection.

Abscess wound caused by bacterial infection is usually difficult to heal, thus greatly affect people's quality of life. In this study, a biodegradable drug-loaded microneedle patch (MN) is designed for targeted eradication of S. aureus infection and repair of abscess wound. Firstly, the bacterial responsive composite nanoparticle (Ce6@GNP-Van) with a size of about 182.6 nm is constructed by loading the photosensitizer Ce6 into gelatin nanoparticle (GNP) and coupling vancomycin (Van), which can specifically target S. aureus and effectively shield the phototoxicity of photosensitizer during delivery. When Ce6@GNP-Van is targeted and enriched in the infected regions, the gelatinase secreted by the bacteria can degrade GNP in situ and release Ce6, which can kill the bacteria by generating ROS under laser irradiation. In vivo experiments show that the microneedle is basically degraded in 10 min after inserting into skin, and the abscess wound is completely healed within 13 d after applying Ce6@GNP-Van-loaded MN patch to the abscess wound of the bacterial infected mice with laser irradiation, which can simultaneously achieve the eradication of biofilm and subsequent wound healing cascade activation, showing excellent synergistic antibacterial effect. In conclusion, this work establishes a synergistic treatment strategy to facilitate the repair of chronic abscess wound.

A pH/ultrasonic dual-response step-targeting enterosoluble granule for combined sonodynamic-chemotherapy guided via gastrointestinal tract imaging in orthotopic colorectal cancer.

Colorectal cancer is one of the malignant tumors with high morbidity and lethality. Its efficient diagnosis and treatment has important significance. In this study, the orthotopic cancer model mouse, which could perfectly simulate clinical inflammatory colorectal cancer, was constructed by chemical induction. Based on this model, a new pH/ultrasonic dual-response, step-targeting and precisely controlled-release enteric-coated granule was designed for the combined sonodynamic (SDT)-chemotherapy. The enteric-coated granule was fabricated by enwrapping carboxymethyl chitosan (CMC) on folic acid-modified phospholipid (SLB-FA) encapsulating mesoporous silicon-coated gold nanoparticles loaded with chlorin (Ce6) and doxorubicin hydrochloride (DOX), titled as Au@mSiO2/Ce6/DOX/SLB-FA@CMC (GMCDS-FA@CMC). The diameter of the Au@mSiO2/Ce6/DOX/SLB-FA (GMCDS-FA) nanoprobe was 61.21 nm and that of the GMCDS-FA@CMC enteric-coated granule was 1.1 µm. MTT results showed that the cell survival rate was still as high as 76.55 ± 1.27% when the concentration of GMCDS-FA was up to 200 µg mL-1, which can indicate the low cytotoxicity of the nanoprobe. According to CT imaging, the enteric-coated granule had the highest concentration in the colorectum of the orthotopic cancer mouse after 7-9 h with oral administration, and was nearly metabolized out of the body after 24 h. The in vitro and in vivo experiments showed that the targeting enteric-coated granule had the best effect of treatment and desired prognosis after combined SDT-chemotherapy.

ROS-augmented and tumor-microenvironment responsive biodegradable nanoplatform for enhancing chemo-sonodynamic therapy.

Nanocarrier for augmenting the efficacy of reactive oxygen species (ROS) by tumor microenvironment (TME) has become an emerging strategy for cancer treatment. Herein, a smart biodegradable drug delivery nanoplatform with mitochondrial-targeted ability, pH-responsive drug release and enzyme-like catalytic function is designed. This efficient ROS-generating platform uses ultrasound with deeper penetration capability as excitation source for combined chemotherapy and sonodynamic therapy (SDT) of tumor. In vitro experiments show that the nanoplatform can co-load Ce6 and DOX and be degraded in slight acid environment, and the DOX release rate is 63.91 ± 1.67%. In vivo experiments show that the nanoplatform has extremely biosafety and can be enriched in tumor site and excluded from body after 24 h. More significantly, after combined treatment, the tumors are eliminated and the mice still survive healthily without recurrence after 60 d. This is because not only it can achieve mitochondrial targeting and use platinum particle to increase oxygen content in TME to enhance the effect of SDT, but also it can use weak acidic TME to accelerate drug release to achieve the combination of chemotherapy and SDT. The probe provides a new strategy for designing ROS-based nanoplatform for the treatment of malignant tumor.

Red blood cell membrane-enveloped O2 self-supplementing biomimetic nanoparticles for tumor imaging-guided enhanced sonodynamic therapy.

Non-invasive sonodynamic therapy (SDT) was developed because of its advantages of high penetration depth and low side effects; however, tumor hypoxia greatly restricts its therapeutic effect. In this study, we aimed to develop ideal O2 self-supplementing nanoparticles for imaging-guided enhanced sonodynamic therapy of tumors with the adept coalescence of biology with nanotechnology. Methods: Based on the natural enzyme system of red blood cells (RBC), biomimetic nanoparticles (QD@P)Rs were fabricated by encapsulating Ag2S quantum dots (QD) in RBC vesicle membranes. The anti-tumor drug PEITC was employed to increase the intracellular H2O2 concentration in tumor cells. Results:In vitro and in vivo experiments demonstrated excellent biocompatibility and prolonged blood circulation of (QD@P)Rs. Following oral administration of PEITC in mice to improve the H2O2 concentration, the enzyme in the nanoprobe catalyzed endogenous H2O2 to increase O2 content and effectively alleviate tumor hypoxia. Triggered by ultrasound under the guidance of fluorescence imaging, (QD@P)Rs generated reactive oxygen species (ROS) to induce tumor cell death, and the increased content of O2 significantly enhanced the effect of SDT. Conclusion: Ag2S QDs were used, for the first time, as a sonosensitizer in the SDT field. In this study, we integrated the advantages of the natural enzyme system and SDT to develop a novel approach for effective non-invasive treatment of cancer.

A pH/Ultrasound dual-response biomimetic nanoplatform for nitric oxide gas-sonodynamic combined therapy and repeated ultrasound for relieving hypoxia.

Sonodynamic therapy (SDT) has rapidly developed as a powerful alternative to traditional photodynamic therapy due to its intrinsically deeper tissue-penetration. However, single SDT dose is incapable of radical cure because the long-term hypoxia of tumor limits its therapeutic effect. Herein, we developed a biomimetic nanoplatform with dual pH/ultrasound response, homologous targeting and low phototoxicity for combined nitric oxide (NO) gas therapy with SDT to solve the problem. This nanoplatform is composed of zeolite imidazole framework-8 material embedded with nitrosoglutathione (GSNO) and chlorin e6 (Ce6) by one-step encapsulation, and then wrapped by homologous tumor cell membrane. In vitro and in vivo experiments indicate that the biomimetic nanoplatform has excellent biocompatibility and shows higher retention in tumor by homologous targeting. Importantly, it can sustainably release the encapsulated drug in acidic tumor microenvironment and accelerate degradation by ultrasound (US). Furthermore, NO released from GSNO and reactive oxygen species generated by Ce6, which are both triggered by US, react with each other to produce highly reactive peroxynitrite to inhibit the growth of tumor. Moreover, by repeated US irradiation, the tumor hypoxia can be relieved for a much-longer term, resulting in an effective gas-sonodynamic combined treatment. This study fully utilizes the advantages of US, providing a new strategy for high-performance cancer therapy.

MFAP2 promotes epithelial-mesenchymal transition in gastric cancer cells by activating TGF-ß/SMAD2/3 signaling pathway.

INTRODUCTION: Microfibril-associated protein 2 (MFAP2) is an extracellular matrix protein that interacts with fibrillin to modulate the function of microfibrils. MFAP2 has been reported to play a significant role in obesity, diabetes, and osteopenia, and has been shown to be upregulated in head and neck squamous cell carcinoma. However, the molecular function and prognostic value of MFAP2 have never been reported in gastric cancer (GC) or any other tumors. METHODS: The current study investigated the expression patterns, prognostic significance, functional role, and possible mechanisms of MFAP2 in GC. RESULTS: We demonstrated that MFAP2 was overexpressed in GC tissues, and its overexpression was significantly correlated with poor overall and disease-free survival in patients with GC. Moreover, we found that MFAP2 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) phenotype in GC cells. MFAP2 might modulate EMT of GC cells by activating the TGF-ß/SMAD2/3 signaling pathway. CONCLUSION: These findings provide novel evidence that MFAP2 plays a crucial role in the progression of GC. Therefore, MFAP2 may be a promising prognostic marker and a potent anticancer agent.