Minimally invasive co-injection of modular micro-muscular and micro-vascular tissues improves in situ skeletal muscle regeneration.

Various conventional treatment strategies for volumetric muscle loss (VML) are often hampered by the extreme donor site morbidity, the limited availability of quality muscle flaps, and complicated, as well as invasive surgical procedures. The conventional biomaterial-based scaffolding systems carrying myoblasts have been extensively investigated towards improving the regeneration of the injured muscle tissues, as well as their injectable forms. However, the applicability of such designed systems has been restricted due to the lack of available vascular networks. Considering these facts, here we present the development of a unique set of two minimally invasively injectable modular microtissues, consisting of mouse myoblast (C2C12)-laden poly(lactic-co-glycolic acid) porous microspheres (PLGA PMs), or the micro-muscles, and human umbilical vein endothelial cell (HUVEC)-laden poly(ethylene glycol) hollow microrods (PEG HMs), or the microvessels. Besides systematic in vitro investigations, the myogenic performance of these modular composite microtissues, when co-injected, was explored in vivo using a mouse VML model, which confirmed improved in situ muscle regeneration and remolding. Together, we believe that the construction of these injectable modular microtissues and their combination for minimally invasive therapy provides a promising method for in situ tissue healing.

Biodegradable Quantum Composites for Synergistic Photothermal Therapy and Copper-Enhanced Chemotherapy.

In recent times, the combination therapy has garnered enormous interest owing to its great potential in clinical research. It has been reported that disulfiram, a clinical antialcoholism drug, could be degraded to diethyldithiocarbamate (DDTC) in vivo and subsequently result in the copper-DDTC complex (Cu(DDTC)2) toward ablating cancer cells. In addition, the ultrasmall copper sulfide nanodots (CuS NDs) have shown great potential in cancer treatment because of their excellent photothermal and photodynamic therapeutic efficiencies. Herein, by taking advantage of the interactions between CuS and DDTC, a new multifunctional nanoplatform based on DDTC-loaded CuS (CuS-DDTC) NDs is successfully fabricated, leading to the achievement of the synergistic effect of photothermal and copper enhanced chemotherapy. All experimental results verified promising synergistic therapeutic effects. Moreover, in vivo biocompatibility and metabolism experiments displayed that the CuS-DDTC NDs could be quickly excreted from the body with no apparent toxicity signs. Together, our findings indicated the superior synergistic therapeutic effect of photothermal and copper-enhanced chemotherapy, providing a promising anticancer strategy based on the CuS-DDTC NDs drug delivery system.

Near-Infrared-Activated Lysosome Pathway Death Induced by ROS Generated from Layered Double Hydroxide-Copper Sulfide Nanocomposites.

The overdeveloped lysosomes in cancer cells are gaining increasing attention toward more precise and effective organelle-targeted cancer therapy. It is suggested that rod/plate-like nanomaterials with an appropriate size exhibited a greater quantity and longer-term lysosomal enrichment, as the shape plays a notable role in the nanomaterial transmembrane process and subcellular behaviors. Herein, a biodegradable platform based on layered double hydroxide-copper sulfide nanocomposites (LDH-CuS NCs) is successfully prepared via in situ growth of CuS nanodots on LDH nanoplates. The as-prepared LDH-CuS NCs exhibited not only high photothermal conversion and near-infrared (NIR)-induced chemodynamic and photodynamic therapeutic efficacies, but also could achieve real-time in vivo photoacoustic imaging (PAI) of the entire tumor. LDH-CuS NCs accumulated in lysosomes would then generate extensive subcellular reactive oxygen species (ROS) in situ, leading to lysosomal membrane permeabilization (LMP) pathway-associated cell death both in vitro and in vivo.

PIN1 Inhibition Sensitizes Chemotherapy in Gastric Cancer Cells by Targeting Stem Cell-like Traits and Multiple Biomarkers.

Gastric cancer is the third leading cause of cancer-related death worldwide. Diffuse type gastric cancer has the worst prognosis due to notorious resistance to chemotherapy and enrichment of cancer stem-like cells (CSC) associated with the epithelial-to-mesenchymal transition (EMT). The unique proline isomerase PIN1 is a common regulator of oncogenic signaling networks and is important for gastric cancer development. However, little is known about its roles in CSCs and drug resistance in gastric cancer. In this article, we demonstrate that PIN1 overexpression is closely correlated with advanced tumor stages, poor chemo-response and shorter recurrence-free survival in diffuse type gastric cancer in human patients. Furthermore, shRNA-mediated genetic or all-trans retinoic acid-mediated pharmaceutical inhibition of PIN1 in multiple human gastric cancer cells potently suppresses the EMT, cell migration and invasion, and lung metastasis. Moreover, PIN1 genetic or pharmaceutical inhibition potently eliminates gastric CSCs and suppresses their self-renewal and tumorigenicity in vitro and in vivo Consistent with these phenotypes, are that PIN1 biochemically targets multiple signaling molecules and biomarkers in EMT and CSCs and that genetic and pharmaceutical PIN1 inhibition functionally and drastically enhances the sensitivity of gastric cancer to multiple chemotherapy drugs in vitro and in vivo These results demonstrate that PIN1 inhibition sensitizes chemotherapy in gastric cancer cells by targeting CSCs, and suggest that PIN1 inhibitors may be used to overcome drug resistance in gastric cancer.

Endothelialized microrods for minimally invasive in situ neovascularization.

Despite the significant advancements in fabricating various scaffolding systems over the past decades, generation of functional tissues towards vascularization remains challenging for the currently available biofabrication approaches. On the other hand, the applicability of traditional surgical transplantation of vascularized tissue constructs is sometimes limited due to the sophisticated surgical procedures, which are invasive, leading to increased risks of scar formation and infection. Considering these facts, we present an innovative platform, the angiogenic microrods composed of sodium alginate/gelatin harboring proliferating endothelial cells using a specially designed double T-junction microfluidic device with an expansion chamber, for achieving minimally invasive neovascularization in situ. Such vessel-like microarchitectures could be derived through controlled penetration of the crosslinker genepin for the gelatin phase, ensuing differential degrees in crosslinking of peripheral and central portions of the microstructures, thus resulting in the formation of vascular lumen-like hollow cavities via endothelial cell migration and proliferation during culture in vitro. Furthermore, in vivo performance of the microrods was explored. We believe that the development of these modular microrods for minimally invasive delivery is of great interest and offers a convenient approach for vascularization in situ.

Highly Porous Microcarriers for Minimally Invasive In Situ Skeletal Muscle Cell Delivery.

Microscale cell carriers have recently garnered enormous interest in repairing tissue defects by avoiding substantial open surgeries using implants for tissue regeneration. In this study, the highly open porous microspheres (HOPMs) are fabricated using a microfluidic technique for harboring proliferating skeletal myoblasts and evaluating their feasibility toward cell delivery application in situ. These biocompatible HOPMs with particle sizes of 280-370 µm possess open pores of 10-80 µm and interconnected paths. Such structure of the HOPMs conveniently provide a favorable microenvironment, where the cells are closely arranged in elongated shapes with the deposited extracellular matrix, facilitating cell adhesion and proliferation, as well as augmented myogenic differentiation. Furthermore, in vivo results in mice confirm improved cell retention and vascularization, as well as partial myoblast differentiation. These modular cell-laden microcarriers potentially allow for in situ tissue construction after minimally invasive delivery providing a convenient means for regeneration medicine.

Supercritical Fluid-Assisted Porous Microspheres for Efficient Delivery of Insulin and Inhalation Therapy of Diabetes.

Pulmonary delivery of drugs has attracted increasing attention in healthcare, as the lungs are an easily accessible site for noninvasive systemic delivery of drugs. Although pulmonary inhalation of porous microparticles has been shown to sustain drug delivery, there are limited reports on efficient delivery of insulin and inhalation therapy of diabetes based on supercritical carbon dioxide (SC-CO2 ) technology. Herein, this study reports the fabrication of insulin-loaded poly-l-lactide porous microspheres (INS-PLLA PMs) by using the SC-CO2 technology, and their use as an inhalation delivery system potentially for diabetes therapy. Biocompatibility and delivery efficiency of the PLLA PMs in the lungs are investigated. The PLLA PMs show negligible toxicity to lung-derived cells, resulting in no significant reduction in cell viability, as well as levels of various inflammatory mediators such as interleukin (IL)-6, IL-8, and tumor necrosis factor-α, compared with the negative control group. INS-PLLA PMs are further efficiently deposited in the trachea and the bronchi of superior lobes of the lungs, which exhibit pronounced hypoglycemic activity in induced diabetic rats. Together, the results demonstrate that the INS-PLLA PMs have a strong potential as an effective strategy for inhalation treatment of diabetes.

Supercritical Fluid-Assisted Decoration of Nanoparticles on Porous Microcontainers for Codelivery of Therapeutics and Inhalation Therapy of Diabetes.

The impact of nanotechnology and its advancements have allowed us to explore new therapeutic modalities. To this end, we designed nanoparticles-inlaid porous microparticles (NIPMs) coloaded with small interfering RNA (siRNA) and glucagon-like peptide-1 (GLP-1) using the supercritical carbon dioxide (SC-CO2) technology as an inhalation delivery system for diabetes therapy. siRNA-encapsulating chitosan (CS) nanoparticles were first synthesized by an ionic gelation method, which resulted in particles with small sizes (100-150 nm), high encapsulation efficiency (∼94.8%), and sustained release performance (∼60% in 32 h). These CS nanoparticles were then loaded with GLP-1-dispersed poly-l-lactide (PLLA) porous microparticles (PMs) by SC-CO2-assisted precipitation with the compressed antisolvent (PCA) process. The hypoglycemic efficacy of NIPMs administered via pulmonary route in mice persisted longer due to sustained release of siRNA from CS nanoparticles and the synergistic effects of GLP-1 in PMs, which significantly inhibited the expression of dipeptidyl peptidase-4 mRNA (DPP-4-mRNA). This ecofriendly technology provides a convenient way to fabricate nanoparticle-microparticle composites for codelivery of a gene and a therapeutic peptide, which will potentially find widespread applications in the field of pharmaceutics.

Supercritical Fluid-Assisted Fabrication of Indocyanine Green-Encapsulated Silk Fibroin Nanoparticles for Dual-Triggered Cancer Therapy.

Despite the success and advantages over traditional chemotherapeutic strategies, photothermal therapy (PTT) suffers from certain limitations, such as poor stability, low therapeutic efficacy of PTT agents in vivo, and their affinity loss during the multistep synthesis process of delivery carriers, among others. To address these limitations, we designed a stable, biocompatible, and dual-triggered formulation of indocyanine green (ICG)-encapsulated silk fibroin (SF) (ICG-SF) nanoparticles using supercritical fluid (SCF) technology. We demonstrated that ICG encapsulation in SF through this environmental-friendly approach has offered excellent photothermal stability, the pH-responsive release of ICG from SF specifically in the tumor acidic environment, and its substantial activation with near-infrared (NIR) light at 808 nm significantly enhanced the PTT efficiency. In vitro and in vivo photothermal experiments have shown that these ICG-SF nanoparticles were capable of devastating tumor cells merely under light-induced hyperthermia. Together, these results have suggested that the biocompatible ICG-SF nanoparticles prepared by the SCF process resulted in high PTT efficiency and may have a great potential as a delivery system for sustained cancer therapy.

Increased micro-RNA 17, 21, and 192 gene expressions improve early diagnosis in non-small cell lung cancer.

Lung cancer is the most commonly diagnosed type of cancer worldwide. About 90 % lung cancer patients died within 5 years after diagnosis. It is reasonable to assume that early detection of lung cancer could reduce mortality. MicroRNAs (miRNAs) are a class of small noncoding, single-stranded RNAs that regulate gene expression by affecting the stability or the translation efficiency of target messenger RNAs. Altered expressions of miRNAs were associated with the development, invasion, metastasis and prognosis of cancer. Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Here, we describe a blood test based on detection of serum miRNAs that distinguish early NSCLC patients from healthy volunteers. Three miRNAs, miR-17, 21 and 192 expression levels were significantly higher in the stage I NSCLC patients than the healthy volunteer groups. This suggests that miR-17, 21 and 192 could be considered as biomarkers for diagnosis of early-stage NSCLC.

[Establishment of obliterative bronchiolitis in allo-trachea transplant model of rat and detection of its pathogenesis preliminarily].

OBJECTIVE: To establish an animal model of obliterative bronchiolitis (OB) after lung transplantation and investigate the pathogenesis preliminarily. METHODS: Tracheal segments (5 cartilaginous rings each) were transplanted from SD rats to SD rats (Group I) or to Wistar rats (Group II and III). Grafts were implanted into an abdominal cavity and wrapped in the omentum. Animals in Group I and II did not receive CsA, animals in Group III received CsA daily by gastro-tube at 10 mg.kg(-1).d(-1) from beginning to end. Grafts were harvested on day 3, 14, 28 after transplantation as representative time points for 3 phases of injury in the evolution of allograft airway obliteration, then examined histological changes and gene expression of T-helper 1-and T-helper 2-type cytokines [Th1: interleukin-2 (IL-2), interferon-gamma (IFN-gamma); Th2: interleukin-4 (IL-4), interleukin-10 (IL-10)] in grafts. At the same time, effects of CsA were observed on the above-mentioned indices. RESULTS: There was no significant difference in histological changes on day 3 after transplantation among 3 groups (P > 0.05). Tracheas in Group I approached to normal morphology on day 14 after transplantation. Airway epithelium of Group II and III almost lost completely on day 14 after transplantation. There was no significant difference between Group II and Group III (P > 0.05), but there were significant differences between Group I and Group II or Group III. The cross-sectional area of the tracheal lumen was narrowed by approximately (5.0 +/- 1.2)%, (28.5 +/- 5.0)% and (19.4 +/- 2.9)% respectively on day 14 after transplantation in Group I, II and III, there were significant differences among 3 groups. On day 14 after transplantation, tracheas in Group I revealed few lymphocytic infiltration, but it showed dense lymphocytic infiltration in Group II. Tracheas in Group III have much more lymphocyte infiltration than that in Group I, but much less than that in Group II. There were significant differences among 3 groups, too (P < 0.01). The tracheal lumen revealed almost total luminal obstruction (94.8 +/- 3.6)% on day 28 after transplantation in Group II. The cross-sectional area of the tracheal lumen was narrowed by approximately (3.7 +/- 0.8)% and (36.6 +/- 7.6)% respectively in Group I and III on day 28. There were significant differences among 3 groups (P < 0.01). Compared with that on day 14, lymphocytic infiltration had decreased gradually on day 28 in Group II and III. There were significant differences among 3 groups all the same (P < 0.01). In Group II, expression of IL-2, IFN-gamma, IL-4, and IL-10 were much higher than that in Group I. Expression of Th1 cytokines was increased to a greater extent than that of Th2 cytokines in Group II compared with Group I. Allografts in Group III expressed significantly less IL-2 gene transcripts than that in Group II over all the points. There was no significant difference between Group II and III in IFN-gamma, IL-4, and IL-10 gene expression. CONCLUSIONS: Compared with isografts, allografts have more obvious changes, such as epithelial damage, fibroproliferation and lymphocytic infiltration. Th1 and Th2 lymphocyte subtypes contribute to the development of obliterative bronchiolitis in heterotopic trachea transplant model of rat, and changes of their cytokines gene expression may be involved in the pathogenesis. CsA could reduce the development of fibroproliferation and lymphocyte infiltration markedly, but it could not protect airway epithelium. CsA inhibits IL-2 gene transcripts, so it can reduce development of the pathologic lesion of obliterative bronchiolitis to a certain degree.