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As a complex “soil” ecosystem, the tumor microenvironment (TME) plays a crucial role in the occurrence, development and metastasis of tumors. Reprogramming TME can block the interactive network between tumors and extracellular matrix (ECM) / various surrounding cells and contribute to tumor effective damage, which is a potential therapeutic target in oncotherapy. Nanobiomaterials have received more attention due to their excellent drug loading and easy functionalization properties, which have been extensively integrated into the construction of engineered drug delivery nanosystems for TME normalization therapy. It has become a commanding point in the field of anti-tumor therapy. This review intends to present and analyze advanced nanotechnology strategies for normalizing TME from 7 different aspects including the reprogramming of extracellular matrix (ECM), cancer-associated fibroblasts (CAFs), abnormal blood vasculatures, hypoxia, tumor acidosis, tumor-associated macrophages (TAMs) and tumor immune tolerance microenvironment based on the various engineered drug delivery nanosystems. It also discusses the currently existing problems and future development trends, which are expected to be helpful for the translational application of nanomedicine in clinical cancer therapy. This work was financially supported by the National Natural Science Foundation of China (51303218, 51825302, 11472224, 11672246, 11722220, 21274169 and 81760441), the National Key Research and Development Program of China (2016YFC1100300 and 2017YFB0702603), the Fundamental Research Funds for the Central Universities (G2018KY0302 and 3102019YX01003), and the Natural Science Foundation of Shaanxi Province (2019JQ-347).

A visible-light-photoredox-catalyzed intermolecular three-component aminotrifluoromethylation of styrenes with phenylhydrazines and Togni's reagents/fluoroalkyl iodides was developed.

This study aims to investigate the brain gray matter volume (GMV) alterations of pediatric complete thoracolumbar spinal cord injury (SCI) without fracture or dislocation (SCIWOFD) using voxel-based morphometry (VBM) analysis and assess the sensitive neuroimaging biomarkers that may be surrogate targets to enhance brain plasticity. A total of 52 pediatric subjects (age range, 6-12 years), including 25 pediatric SCIWOFD patients and 27 typically developing (TD) children were recruited. An independent two-sample

As the main cells in endochondral osteogenesis, chondrocytes have limited self-repair ability due to weak proliferation activity, low density, and dedifferentiation tendency. Here, a thorough inquiry about the effect and underlying mechanisms of methyltransferase like-3 (Mettl3) on chondrocytes was made. Functionally, it was indicated that Mettl3 promoted the proliferation and hypertrophic differentiation of chondrocytes. Mechanically, Dmp1 (dentin matrix protein 1) was proved to be the downstream direct target of Mettl3 for m

Aqueous bismuth based anodes have received intensive interest in recent years. However, further advances in rate capability and cycling stability remain challenging. Herein, a porous conductive network is first constructed to accommodate the dense growth of 2D BiOI nanosheets, which served as an appropriate precursor of Bi active materials. Benefiting from the porous conductive 3D framework and in situ topotactic transformation of ultrathin BiOI nanosheets, favorable reaction kinetics and effective utilization of active materials are achieved. The resultant binder-free bismuth anode shows a prominent areal capacity (2.17 mA h cm−2 at 1 mA cm−2, 1.48 mA h cm−2 at 128 mA cm−2), long-term stability (93.1% retention after 5000 cycles) and high mass loading of 27 mg cm−2. The mechanism regarding cycling stability is revealed by DFT calculations. In addition, the assembled Ni3S2//Bi full battery exhibits a high energy density of 22.73 mW h cm−3. Considering the facile preparation process and impressive performance of the device, this work proposes a general strategy for constructing advanced aqueous batteries and shows the great potential of bismuth based anodes in large-scale applications.

Local injection of tumor necrosis factor-alpha (TNF-α) at bone fracture sites during the early stage of the inflammatory response is reported to improve fracture repair in a murine model. However, the underlying mechanism is unclear. Endochondral bone formation, a process that is highly related to fracture repair, requires a certain amount of chondrocyte hypertrophy. This study aimed to investigate the effect of TNF-α on the differentiation of murine chondrogenic ATDC5 cells and the underlying mechanism. In this study, improved chondrogenic differentiation of ATDC5 cells was achieved by brief TNF-α stimulation. Moreover, the expression of Yes-associated protein 1 (YAP1) was suppressed after brief TNF-α stimulation. The expressions of inflammatory mediators and chondrogenic and hypertrophic-associated genes in ATDC5 cells triggered by TNF-α were suppressed in the YAP1 overexpression group but enhanced in the YAP1 knockdown group. Mechanistically, TNF-α-induced activation of the 5' AMP-activated protein kinase (AMPK) signaling pathway was regulated by YAP1, as revealed by the phosphorylated-AMPK/AMPK change ratios in the YAP1 overexpression and knockdown groups, respectively. Moreover, the potential for TNF-α to enhance chondrogenic differentiation could be partially reversed with an AMPK inhibitor. Taken together, we demonstrate, for the first time, that YAP1 modulates the ability of TNF-α to enhance chondrocyte differentiation partly through AMPK signaling.

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Yes-associated protein 1 (YAP1) transcriptional coactivator has recently been identified to regulate skeletal lineage cell differentiation and bone development. However, the role and molecular mechanisms of YAP1 in the regulation of osteoblastic differentiation remains to be elucidated. In this study, we demonstrated that YAP1 expression was increased during osteogenic differentiation of rat bone mesenchymal stem cells and MC3T3-E1. YAP1 overexpression MC3T3-E1 showed increased expression of osteogenesis markers, such as runt-related transcription factor 2, osteocalcin, and osteopontin, as well as alkaline phosphatase and alizarin red staining. Conversely, YAP1 knockdown significantly suppressed MC3T3-E1 osteoblastic differentiation. Mechanistically, we found that YAP1 overexpression upregulated the mRNA and protein expression of the inhibitor of differentiation/DNA binding 1 (ID1), which was contrary to the results of YAP1-knockdown group. Moreover, the early osteogenic differentiation of MC3T3-E1 cells was enhanced by ID1 overexpression. Furthermore, transient transfection with exogenous ID1 overexpression plasmid completely recaptured the decreased effects of YAP1 knockdown on MC3T3-E1 cell differentiation. In addition, β-catenin and AMP-activated protein kinase signaling pathways participated in YAP1 regulation processes. Taken together, our study suggests that YAP1 is a crucial modulator of osteoblast differentiation in vitro, and provides insight into the mechanism by which YAP1 regulates osteoblast differentiation.

Endoplasmic reticulum (ER) stress can initiate autophagy via unfolded protein response (UPR). As a key downstream gene of UPR, DDIT3/CHOP is expressed in chondrocytes. However, the regulation mechanism of DDIT3/CHOP on autophagy in chondrocytes remains unclear. In this study, the expression levels of autophagic markers Beclin1 and LC3B were found to decrease while p62 increase in the tibial growth plate and costal primary chondrocytes from DDIT3/CHOP KO mice. In vitro, overexpressing DDIT3/CHOP induced autophagy in ATDC5 chondrocytes, displaying an elevated immunofluorescence signal of LC3B and elevated numbers of autophagosomes and autolysosomes. Analysis of the gain- and loss-of-function indicated that the protein level of Beclin1 and the ratio of LC3BII/I increased in DDIT3/CHOP overexpression cells, whereas decreased in DDIT3/CHOP knockdown cells. The decreased level of p62 and additional accumulation of LC3BII caused by chloroquine (CQ) further indicated that DDIT3/CHOP enhanced autophagic flux. Mechanistically, we found that DDIT3/CHOP binds directly to the promoter of SIRT1 to promote its expression by CHIP, qRT-PCR, and Western blot analysis. In addition, SIRT1 enhanced autophagic activity in ATDC5 cells, and inhibition or activation of SIRT1 partially reversed the effect of overexpressing or downregulating DDIT3/CHOP on autophagy. Furthermore, AKT signaling was found to be responsible for DDIT3/CHOP-regulated autophagy in ATDC5 cells. SIRT1 knockdown reversed the effect of DDIT3/CHOP overexpression on AKT signaling. In conclusion, our data clarifies that DDIT3/CHOP promotes autophagy in ATDC5 chondrocytes through the SIRT1-AKT pathway. These results were also confirmed in the primary chondrocytes.

N6-methyladenosine (m6A) methylation is one of the most common internal modifications in eukaryotic messenger RNA occurring on N6 nitrogen of adenosine. However, the roles of m6A in temporomandibular joint osteoarthritis (TMJ OA) are still elusive. Here, we investigate the function and mechanism of methyltransferase-like 3 (Mettl3) in chondrocytes in inflammation. We found that the expression of Mettl3 decreased both in vivo TMJ OA mice and in vitro inflammatory stimulation. Functionally, loss and gain studies illustrated that Mettl3 inhibited the apoptosis and autophagy of chondrocytes induced by TNF-α stimulation in vitro. Mettl3 inhibitor, S-adenosylhomocysteine (SAH) promoted the apoptosis and autophagy of chondrocytes with inflammation in vitro and aggravated the degeneration of chondrocytes and subchondral bone in monosodium iodoacetate (MIA) induced TMJ OA mice in vivo. Mechanistically, the bioinformatics analysis, m6A-RNA immunoprecipitation (MeRIP) and RNA immunoprecipitation (RIP) were used to identify that Bcl2 mRNA was the downstream target of Mettl3 for m6A modification. Furthermore, the results revealed that Yth m6A RNA binding protein 1 (Ythdf1) mediated the stability of Bcl2 mRNA catalyzed by Mettl3. Co-immunoprecipitation (Co-IP) showed that Bcl2 protein interacted with Beclin1 protein in chondrocytes induced by TNF-α stimulation. In conclusion, our findings identify that Mettl3 inhibits the apoptosis and autophagy of chondrocytes in inflammation through m6A/Ythdf1/Bcl2 signal axis which provides promising therapeutic strategy for TMJ OA.

DNA damage-inducible transcript 3 (DDIT3), a member of the CCAAT/enhancer-binding protein (C/EBP) family, is involved in cellular apoptosis and differentiation. DDIT3 participates in the regulation of adipogenesis and osteogenesis in vitro and in vivo. However, the role of DDIT3 in osteoclastogenesis is not yet known. In this study, the involvement of DDIT3 in osteoclast differentiation and function was reported for the first time. CRISPR/Cas9-mediated DDIT3 knockout (KO) mice were generated for functional assessment. Tartrate-resistant acid phosphatase (TRAP) staining of distal femurs showed increased positive cells in DDIT3 KO mice. DDIT3 expression was downregulated during the receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation of bone marrow-derived macrophages (BMMs). The loss of DDIT3 increased the expression of osteoclast-specific markers, including nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), TRAP, cathepsin K (CTSK), and dendritic cell-specific transmembrane protein (DC-STAMP) and promoted the formation of TRAP-positive multinucleated osteoclasts. The actin ring number and resorption area of bone slices were also increased in DDIT3 KO BMMs. Lentivirus-mediated DDIT3 overexpression significantly inhibited the osteoclast differentiation of RAW264.7 cells. In the tumor necrosis factor-α-induced osteolysis model, DDIT3 deficiency enhanced osteoclast formation and aggravated bone resorption. DDIT3 inhibited osteoclast differentiation by regulating the C/EBPα-CTSK axis. Furthermore, DDIT3 KO intensified the RANKL-triggered activation of the MAPKs and Akt signaling pathways. Taken together, the results revealed the essential role of DDIT3 in osteoclastogenesis in vitro and in vivo and its close relationship with osteoclast-associated transcription factors and pathways.

Yes-associated protein 1 (YAP1) transcriptional coactivator is a mediator of mechanosensitive signaling. Cementum, which covers the tooth root surface, continuously senses external mechanical stimulation. Cementoblasts are responsible for the mineralization and maturation of the cementum. However, the effect of YAP1 on cementoblast differentiation remains largely unknown. In this study, we initially demonstrated that YAP1 overexpression enhanced the mineralization ability of cementoblasts. YAP1 upregulated the mRNA and protein expression of several cementogenesis markers, such as alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), and dentin matrix acidic phosphoprotein 1 (DMP1). The YAP1 overexpression group showed higher intensities of ALP and Alizarin red stain than the YAP1-knockdown group. Unexpectedly, a sharp increase in the expression of dentin sialophosphoprotein (DSPP) was induced by the overexpression of YAP1. Knockdown of YAP1 suppressed DSPP transcriptional activity. YAP1 overexpression activated Smad-dependent BMP signaling and slightly inhibited Erk1/2 signaling pathway activity. Treatment with specific BMP antagonist (LDN193189) prevented the upregulation of the mRNA levels of ALP, RUNX2, and OCN, as well as intensity of ALP-stained and mineralized nodules in cementoblasts. The Erk1/2 signaling pathway inhibitor (PD 98,059) upregulated these cementogenesis markers. Thus, our study suggested that YAP1 enhanced cementoblast mineralization in vitro. YAP1 exerted its effect on the cementoblast partly by regulating the Smad-dependent BMP and Erk1/2 signaling pathways.

Yes-associated protein 1 (YAP1), the core downstream effector of the Hippo signaling cascade, was involved in the regulation of osteoblast and osteoclast differentiation and in bone metabolism. However, the regulatory effects and mechanisms of YAP1 on bone-remodeling molecules in osteoblasts under inflammation remain unknown. In this study, YAP1 expression level was downregulated after treatment with inflammatory cytokine tumor necrosis factor-α (TNF-α) in MC3T3-E1 cells. The key osteoclastogenic molecules induced by TNF-α, namely, interleukin-6 and receptor activator of nuclear factor-κB (NF-κB) ligand, were suppressed after lentivirus-induced YAP1 overexpression, which dramatically increased the expression level of osteoprotegerin. Conversely, the expression levels of the above factors showed opposite trends in the YAP1 small interfering RNA and YAP1 inhibitor (verteporfin) group. Mechanistically, YAP1 attenuated the TNF-α-induced activation of the NF-κB signaling pathway as revealed by the reduced expression of phosphorylated-p65 and NF-κB reporter activity and the nuclear translocation of p65. Moreover, the expression level of YAP1 suppressed by TNF-α was reversed by berberine in concentration-dependent manner. Taken together, our study suggests that YAP1 plays a critical role in the regulation of bone metabolism and is a potential therapeutic target for treating inflammatory bone resorption.

DDIT3 is of great importance in endoplasmic reticulum stress and is involved in many inflammatory diseases and mineralization processes. The cementum protects teeth from periodontitis and provides attachment for Sharpey's fibers of the periodontal ligament. However, the effect of DDIT3 on cementoblast differentiation remains largely unknown. In this study, we found that DDIT3 was suppressed during cementoblast differentiation. Knockdown of DDIT3 increased the messenger RNA (mRNA) and protein levels of several key osteogenic markers in vitro, including alkaline phosphatase, runt-related transcription factor 2, and osteocalcin (OCN). In addition, isocitrate dehydrogenase 1 (IDH1) was increased during cementoblast differentiation, and knockdown of DDIT3 increased the protein and mRNA levels of IDH1. Furthermore, inhibition of IDH1 could partially reduce the effect of DDIT3 on cementoblast differentiation. The DDIT3 knockdown activated nuclear factor-κB (NF-κB) transcriptional activity and upregulated the expression of p-p65 and p-IκBα. The increased osteogenic differentiation ability and IDH1 expression, as induced by the DDIT3 knockdown, could be partially turned over by the addition of NF-κB inhibitor BAY 11-7082. Overall, our data clarified that DDIT3 suppresses cementoblast differentiation through IDH1, via the NF-κB pathway.

YAP1 (Yes-associated protein 1) transcriptional coactivator is a downstream gene of the Hippo signaling pathway, which controls cell proliferation and differentiation. YAP1 plays a significant role in the regulation of cartilage and bone development. However, the molecular mechanism by which YAP1 regulates chondrocyte differentiation remains to be elucidated. Immunofluorescent staining was used to visualize the localization of YAP1 expression in the mouse chondroprogenitor ATDC5 cell line. ATDC5 cells with lentivirus-vector-mediated YAP1 overexpression and knockdown were established. The differentiation abilities were examined by real-time quantitative PCR and two staining methods The expression levels of sex-determining region Y-type high mobility group box protein (SOX9) and key proteins in the Wnt/β-catenin pathway were analyzed by Western blot. The Dickkopf-1 (Dkk1) and small interfering RNA (siRNA) of β-catenin were used for further study. The YAP1 protein was mainly expressed in the nucleus of ATDC5 cells. YAP1 overexpression enhanced chondrocyte proliferation but inhibited chondrocyte differentiation, which were contrary to the findings of the YAP1-knockdown group. Moreover, YAP1 overexpression activated Wnt/β-catenin signaling pathway. Treatment with exogenous DKK1 and β-catenin siRNA partially recaptured the effects of YAP1 overexpression on ATDC5 cell differentiation. Taken together, our study suggested that YAP1 attenuated ATDC5 cell chondrogenic and hypertrophic differentiation. We also demonstrated that YAP1 exerted its effect on the chondrocyte differentiation by activating the Wnt/β-catenin signaling pathway.

Polyamines (PAs) induce nitric oxide (NO) generation in plant tissues; however, their mechanism is still unclear. In the present study, suspension cells of soybean cotyledon-node callus were employed. Using a NO-specific fluorescent dye, DAF-FM-DA (3-amino, 4-aminomethyl-2', 7'-difluorescein, diacetate), and laser confocal scanning microscopy, changes in NO generation induced by exogenous PAs were examined. The results of this study showed that NO fluorescence was significantly induced above endogenous levels when callus cells were treated with 0.05 mM PAs. However, putrescine (Put) was the most active PA. The observed NO release by PAs was rapid and without an apparent lag phase. The response was quenched when the suspension cells were treated with the NO-specific scavenger cPTIO (2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-1-oxy-3-oxide). When 0.01 mM l-aminoguanidine (L-AG) was applied prior to the PA treatments, the NO fluorescence was diminished, and the inhibition of NO fluorescence was correlated with a decrease in diamine oxidase (DAO) activity. When callus cells were incubated with 0.1 mM catalase (CAT) and 1.0 mM N'N-dimethylthiourea (DMTU) prior to PA application, NO release was significantly reduced. In sum, our data provided evidence for PA-induced NO generation in suspension cells of soybean cotyledon node callus and demonstrated that peroxide, potentially derived from PA oxidative degradation, was involved in NO release induced by PAs.