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Formation of functional and perfusable vascular network is critical to ensure the long‐term survival and functionality of the engineered tissue tracheae after transplantation. However, the greatest challenge in tracheal‐replacement therapy is the promotion of tissue regeneration by rapid graft vascularization. Traditional prevascularization methods for tracheal grafts typically utilize omentum or muscle flap wrapping, which requires a second operation; vascularized segment tracheal orthotopic transplantation in one step remains difficult. This study proposes a method to construct a tissue‐engineered tracheal graft, which directly forms the microvascular network after orthotopic transplantation in vivo. The focus of this study was the preparation of a hybrid tracheal graft that is non‐immunogenic, has good biomechanical properties, supports cell proliferation, and quickly vascularizes. The results showed that vacuum‐assisted decellularized trachea‐polycaprolactone hybrid scaffold could match most of the above requirements as closely as possible. Furthermore, endothelial progenitor cells (EPCs) were extracted and used as vascularized seed cells and seeded on the surfaces of hybrid grafts before and during the tracheal orthotopic transplantation. The results showed that the microvascularized tracheal grafts formed maintained the survival of the recipient, showing a satisfactory therapeutic outcome. This is the first study to utilize EPCs for microvascular construction of long‐segment trachea in one‐step; the approach represents a promising method for microvascular tracheal reconstruction. [ABSTRACT FROM AUTHOR]

The construction of ideal tissue engineering trachea has always been a difficult problem in trachea transplantation surgery. The biological characteristics of decellularized matrix prepared by detergent‐enzymatic (DEM) and 3D printing biomimetic scaffold (PTS) in vivo and in vitro were compared. In order to comprehensively evaluate its performance, we tested morphological and biomechanical characteristics of the native tracheas(Group A), DEM(Group B), and PTS(Group C). The above groups were co‐cultured with bone marrow mesenchymal stem cells (BMSCs), after which cell attachment and proliferation on the scaffolds were detected. Allogeneic implantation experiments were performed to assess the in vivo biocompatibility of the studied scaffolds. Moreover, an in‐situ experiment of the tracheal repair was conducted to compare the survival of every group. The biomechanical properties of PTS were significantly better than those of other scaffolds (P <.05). And they retained their structural integrity in the host compared with the other scaffolds (P <.05). Besides, significantly milder immune‐rejection reactions were observed in Group C than those in Group A (P <.05). In situ experiments showed that Group C significantly a good postoperative condition compared with the other scaffold groups (P <.05). Fiberoptic bronchoscopy analysis of PTS showed a better condition in the lumen. In conclusion, PTS has excellent biomechanical properties. Although the PTS group showed lower biocompatibility than the decellularized group, it exhibited better cell attachment and proliferation. In situ transplantation results showed that PTS could be an ideal source of tissue engineering material for tracheal repair. [ABSTRACT FROM AUTHOR]

Shear stress was reported to regulate the expression of AC007362, but its underlying mechanisms remain to be explored. In this study, to isolate endothelial cells of blood vessels, unruptured and ruptured intracranial aneurysm (IA) tissues were collected from IA patients. Subsequently, quantitative real‐time PCR (qRT‐PCR), Western blot and luciferase assay were performed to investigate the relationships between AC007362, miRNAs‐493 and monocyte chemoattractant protein‐1 (MCP‐1) in human umbilical vein endothelial cells (HUVECs) exposed to shear stress. Reduced representation bisulphite sequencing (RRBS) was performed to assess the level of DNA methylation in AC007362 promoter. Accordingly, AC007362 and MCP‐1 were significantly up‐regulated while miR‐493 was significantly down‐regulated in HUVECs exposed to shear stress. AC007362 could suppress the miR‐493 expression and elevate the MCP‐1 expression, and miR‐493 was shown to respectively target AC007362 and MCP‐1. Moreover, shear stress in HUVECs led to the down‐regulated DNA methyltransferase 1 (DNMT1), as well as the decreased DNA methylation level of AC007362 promoter. Similar results were also observed in ruptured IA tissues when compared with unruptured IA tissues. In conclusion, this study presented a deep insight into the operation of the regulatory network of AC007362, miR‐493 and MCP‐1 upon shear stress. Under shear stress, the expression of AC007362 was enhanced by the inhibited promoter DNA methylation, while the expression of MCP‐1 was enhanced by sponging the expression of miR‐493. [ABSTRACT FROM AUTHOR]

The influences of pore sizes and surface modifications on biomechanical properties and biocompatibility (BC) of porous tracheal scaffolds (PTSs) fabricated by polycaprolactone (PCL) using 3D printing technology. The porous grafts were surface‐modified through hydrolysis, amination, and nanocrystallization treatment. The surface properties of the modified grafts were characterized by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The materials were cocultured with bone marrow mesenchymal stem cells (BMSCs). The effect of different pore sizes and surface modifications on the cell proliferation behavior was evaluated by the cell counting kit‐8 (CCK‐8). Compared to native tracheas, the PTS has good biomechanical properties. A pore diameter of 200 μm is the optimum for cell adhesion, and the surface modifications successfully improved the cytotropism of the PTS. Allogeneic implantation confirmed that it largely retains its structural integrity in the host, and the immune rejection reaction of the PTS decreased significantly after the acute phase. Nano‐silicon dioxide (NSD)‐modified PTS is a promising material for tissue engineering tracheal reconstruction. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 360–370, 2019. [ABSTRACT FROM AUTHOR]

Background: For many years, lung cancer has been the most common and deadly cancer worldwide. Early diagnosis of non‐small cell lung cancer (NSCLC) in particular is very difficult because the symptoms are often ignored. The five‐year survival rate is very low despite great improvements to therapy. Thus, there is an urgent need to identify prognostic biomarkers and target molecules for the clinical diagnosis and individualized treatment of NSCLC. Methods: We performed quantitative real‐time PCR to determine the expression levels of the long non‐coding RNA (lncRNA) linc01433 in NSCLC and normal matched lung tissue. Subsequently, we established cell lines with overexpression or knockdown of linc01433 to evaluate the effects on proliferation and metastasis in vitro. Epithelial‐to‐mesenchymal transition was examined using Western blot. Results: Linc01433 was significantly overexpressed in NSCLC tissues compared to normal lung tissues. In addition, linc01433 levels were associated with smoking history. Linc01433 overexpression in lung cancer cells increased proliferation, migration, and invasion abilities, as well as epithelial‐to‐mesenchymal transition. Conclusions: Linc01433 is a cancer‐related lncRNA that may have an oncogene‐like effect in NSCLC. [ABSTRACT FROM AUTHOR]