The Success of Fabrication of Pure SmFe2 Phase Film with Outstanding Perpendicular Magnetic Anisotropy.

This study used DC magnetron sputtering technology to fabricate Sm-Fe films and systematically investigated the phase transition behavior of Sm-Fe films with different Fe ratios. It was found that at higher Fe content, the films consisted of Sm2Fe17 or SmFe7 phases; as Fe content decreased, the films were mainly composed of SmFe3 or SmFe2 phases; at higher Sm content, the films primarily consisted of Sm phase. Sm is prone to volatilization at high temperatures, so Ta was used as a capping layer to effectively suppress Sm volatilization, successfully synthesizing pure SmFe2 phase films at a nearly 1:2 ratio. The magnetic properties and magnetostrictive behavior of the SmFe2 films were investigated, revealing that pure-phase SmFe2 films exhibit good perpendicular magnetic anisotropy and magnetostriction properties. The larger stress along the perpendicular-to-film direction, resulting from the absence of substrate-induced constraints, contributes to the excellent perpendicular magnetic anisotropy of the films. This study successfully synthesized pure-phase SmFe2 films and discovered a new method for fabricating perpendicularly anisotropic films. The research findings are of great significance for the efficient synthesis of desired films with high phase formation temperatures containing volatile elements.

Single-cell and spatial transcriptomics reveal metastasis mechanism and microenvironment remodeling of lymph node in osteosarcoma.

BACKGROUND: Osteosarcoma (OS) is the most common primary malignant bone tumor and is highly prone to metastasis. OS can metastasize to the lymph node (LN) through the lymphatics, and the metastasis of tumor cells reestablishes the immune landscape of the LN, which is conducive to the growth of tumor cells. However, the mechanism of LN metastasis of osteosarcoma and remodeling of the metastatic lymph node (MLN) microenvironment is not clear. METHODS: Single-cell RNA sequencing of 18 samples from paracancerous, primary tumor, and lymph nodes was performed. Then, new signaling axes closely related to metastasis were identified using bioinformatics, in vitro experiments, and immunohistochemistry. The mechanism of remodeling of the LN microenvironment in tumor cells was investigated by integrating single-cell and spatial transcriptomics. RESULTS: From 18 single-cell sequencing samples, we obtained 117,964 cells. The pseudotime analysis revealed that osteoblast(OB) cells may follow a differentiation path from paracancerous tissue (PC) → primary tumor (PT) → MLN or from PC → PT, during the process of LN metastasis. Next, in combination of bioinformatics, in vitro and in vivo experiments, and immunohistochemistry, we determined that ETS2/IBSP, a new signal axis, might promote LN metastasis. Finally, single-cell and spatial dissection uncovered that OS cells could reshape the microenvironment of LN by interacting with various cell components, such as myeloid, cancer-associated fibroblasts (CAFs), and NK/T cells. CONCLUSIONS: Collectively, our research revealed a new molecular mechanism of LN metastasis and clarified how OS cells influenced the LN microenvironment, which might provide new insight for blocking LN metastasis.

Biochanin A inhibits endothelial dysfunction induced by IL­6­stimulated endothelial microparticles in Perthes disease via the NFκB pathway.

Endothelial dysfunction caused by the stimulation of endothelial microparticles (EMPs) by the inflammatory factor IL-6 is one of the pathogenic pathways associated with Perthes disease. The natural active product biochanin A (BCA) has an anti-inflammatory effect; however, whether it can alleviate endothelial dysfunction in Perthes disease is not known. The present in vitro experiments on human umbilical vein endothelial cells showed that 0-100 pg/ml IL-6-EMPs could induce endothelial dysfunction in a concentration-dependent manner, and the results of the Cell Counting Kit 8 assay revealed that, at concentrations of <20 µM, BCA had no cytotoxic effect. Reverse transcription-quantitative PCR demonstrated that BCA reduced the expression levels of the endothelial dysfunction indexes E-selectin and intercellular cell adhesion molecule-1 (ICAM-1) in a concentration-dependent manner. Immunofluorescence and western blotting illustrated that BCA increased the expression levels of zonula occludens-1 and decreased those of ICAM-1. Mechanistic studies showed that BCA inhibited activation of the NFκB pathway. In vivo experiments demonstrated that IL-6 was significantly increased in the rat model of ischemic necrosis of the femoral head, whereas BCA inhibited IL-6 production. Therefore, in Perthes disease, BCA may inhibit the NFκB pathway to suppress IL-6-EMP-induced endothelial dysfunction, and could thus be regarded as a potential treatment for Perthes disease.

Single-cell RNA sequencing reveals the immune microenvironment landscape of osteosarcoma before and after chemotherapy.

Chemotherapy, a primary treatment for osteosarcoma (OS), has limited knowledge regarding its impact on tumor immune microenvironment (TIME). Here, tissues from 6 chemotherapy-naive OS patients underwent single-cell RNA sequencing (scRNA-seq) and were analyzed alongside public dataset (GSE152048) containing 7 post-chemotherapy OS tissues. CD45+ (PTPRC+) cells were used for cell clustering and annotation. Changes in immune cell composition pre- and post-chemotherapy were characterized. Totally, 28,636 high-quality CD45+ (PTPRC+) cells were extracted. Following chemotherapy, the proportions of regulatory T cells (Tregs) and activated CD8 T cells decreased, while CD8 effector T cells increased. GO analysis indicated that differentially expressed genes (DEGs) in T cells were associated with cell activation, adaptive immune response, and immune response to tumor cells. Furthermore, the proportions of plasma cells increased, while naive B cells decreased. B cell surface receptors expression was upregulated, and GO analysis revealed DEGs of B cells were mainly enriched in B cell-mediated immunity and B cell activation. Moreover, M2 polarization of macrophages was suppressed post-chemotherapy. Overall, this study elucidates chemotherapy remodels the OS TIME landscape, triggering immune heterogeneity and enhancing anti-tumor properties.

Surgical treatment of an old avulsion fracture of the ischial tuberosity and ischial ramus: A case report.

BACKGROUND: Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities. According to previous literature, the most commonly involved sports are soccer, sprinting, and gymnastics, in descending order. Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare. CASE SUMMARY: A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip. She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior. Eventually, she underwent surgery and obtained satisfactory treatment results. CONCLUSION: Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery. For old fractures with nonunion and chronic buttock pain, surgery is a preferred therapeutic choice with good treatment outcomes.

Prediction of the active compounds and mechanism of Biochanin A in the treatment of Legg-Calvé-Perthes disease based on network pharmacology and molecular docking.

BACKGROUND: Legg-Calvé-Perthes disease is a special self-limited disease in pediatric orthopedics with a high disability rate and a long-term course, and there is still no clear and effective therapeutic drug in clinic. This study aimed to investigate the potential efficacy of biochanin A, a kind of oxygen-methylated isoflavone compound, in treating Perthes disease based on network pharmacology, molecular docking and in vitro experiments. METHODS: IL-6 was used to stimulate human umbilical vein endothelial cells to construct endothelial cell dysfunction model. We demonstrated whether biochanin A could alleviate endothelial dysfunction through CCK8 assay, immunofluorescence. Targets of biochanin A from pharmMappeer, SWISS, and TargetNet databases were screened. Targets of endothelial dysfunction were obtained from Genecards and OMIM databases. Protein-protein interaction, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomics analyses were used to analyze the potential target and the key pathway of the anti-endothelial dysfunction activity of biochanin A. To validate the potential target-drug interactions, molecular docking and molecular dynamics simulations were performed and the result was proved by western blot. RESULTS: It was found that biochanin A can promote the expression of ZO-1, reduce the expression of ICAM-1, which means improving endothelial dysfunction. A total of 585 targets of biochanin A from pharmMappeer, SWISS, and TargetNet databases were screened. A total of 10,832 targets of endothelial dysfunction were obtained from Genecards and OMIM databases. A total of 527 overlapping targets of endothelial dysfunction and biochanin A were obtained. AKT1, TNF-α, VCAM1, ICAM1, and NOS3 might be the key targets of the anti-endothelial dysfunction activity of biochanin A, and the key pathways might be PI3K-Akt and TNF signaling pathways. Molecular docking results indicated that the AKT1 and TNF-α had the highest affinity binding with biochanin A. CONCLUSION: This study indicates that biochanin A can target AKT1 and TNF-α to alleviate endothelial dysfunction induced by IL-6 in Perthes disease, which provides a theoretical basis for the treatment of Perthes disease by using biochanin A.

[Regulation of non-coding RNA in type H vessels angiogenesis of bone].

Objective: To summarize the regulatory effect of non-coding RNA (ncRNA) on type H vessels angiogenesis of bone. Methods: Recent domestic and foreign related literature about the regulation of ncRNA in type H vessels angiogenesis was widely reviewed and summarized. Results: Type H vessels is a special subtype of bone vessels with the ability to couple bone formation. At present, the research on ncRNA regulating type H vessels angiogenesis in bone diseases mainly focuses on microRNA, long ncRNA, and small interfering RNA, which can affect the expressions of hypoxia inducible factor 1α, platelet derived growth factor BB, slit guidance ligand 3, and other factors through their own unique ways of action, thus regulating type H vessels angiogenesis and participating in the occurrence and development of bone diseases. Conclusion: At present, the mechanism of ncRNA regulating bone type H vessels angiogenesis has been preliminarily explored. With the deepening of research, ncRNA is expected to be a new target for the diagnosis and treatment of vascular related bone diseases.

Association of survivin positive circulating tumor cell levels with immune escape and prognosis of osteosarcoma.

PURPOSE: Function of survivin protein (encoded by BIRC5) in circulating tumor cells (CTCs) of osteosarcoma (OS) has not been investigated. The goal of this study is to determine whether the expression of survivin protein of CTCs is associated with circulating immune cell infiltration and disease prognosis of OS. METHODS: Blood samples of 20 patients with OS were collected. CanPatrol™ CTC enrichment technology combined with in situ hybridization (ISH) was applied to enrich and test CTCs and survivin protein. Bioinformation analysis combined with data of routine blood test was used to verify the association between survivin and immune cell infiltration in circulatory system. To screen independent prognostic factors, Kaplan-Meier survival curve, univariate and multivariable Cox regression analyses were performed. RESULTS: Bioinformatics analysis showed that BIRC5 was strongly negatively related to lymphocyte, including T cell, NK cell and B cell, which released that BIRC5 played a key role in immune escape via reducing immune cell infiltration in circulatory system. Meanwhile, the number of survivin+ CTCs was significantly negatively connection with lymphocyte count (R = -0.56, p = 0.011), which was consistent with bioinformatics analysis. Kaplan-Meier curve showed that the overall survival rate in high survivin+ CTCs group was significantly lower than low group (88.9% vs 36.4%, p = 0.04). Multivariable Cox regression analyses showed that survivin+ CTCs were an independent prognostic factor (p = 0.019). CONCLUSION: These findings suggested that survivin protein played a key role in immune escape of CTCs and the presence of survivin+ CTCs might be a promising prognostic factor in OS patients.

A new insight of immunosuppressive microenvironment in osteosarcoma lung metastasis.

The lung is the primary organ for the metastasis of osteosarcoma. Although the application of neoadjuvant chemotherapy and surgery has remarkably improved the survival rate of patients with osteosarcoma, prognosis is still poor for those patients with metastasis. In this study, we performed further bioinformatics analysis on single-cell RNA sequencing (scRNA-seq) data published before, containing 75,317 cells from two osteosarcoma lung metastasis and five normal lung tissues. First, we classified 17 clusters, including macrophages, T cells, endothelial cells, and so on, indicating highly intratumoral heterogeneity in osteosarcoma lung metastasis. Next, we found macrophages in osteosarcoma lung metastasis did not have significant M1 or M2 polarizations. Then, we identified that T cells occupied the most abundant among all cell clusters, and found CD8+ T cells exhibited a low expression level of immune checkpoints in osteosarcoma lung metastasis. What is more, we identified C2_Malignant cells, and found CD63 might play vital roles in determining the infiltration of T cells and malignant cells in conventional-type osteosarcoma lung metastasis. Finally, we unveiled C1_Therapeutic cluster, a subcluster of malignant cells, was sensitive to oxfendazole and mevastatin, and the potential hydrogen-bond position and binding energy of oxfendazole-KIAA0907 and mevastatin-KIAA0907 were unveiled, respectively. Our results highlighted the power of scRNA-seq technique in identifying the complex tumor microenvironment of osteosarcoma lung metastasis, making it possible to devise precision therapeutic approaches.

Achievement of High Perpendicular Anisotropy and Modification of Heat Treatment Peeling in Micron-Thickness Nd-Fe-B Films Used for Magnetic MEMS.

Thick Nd-Fe-B permanent magnetic films with good perpendicular anisotropy have important applications in magnetic microelectromechanical systems (MEMSs). However, when the thickness of the Nd-Fe-B film reaches the micron level, the magnetic anisotropy and texture of NdFeB film will become worse, and it is also prone to peeling during heat treatment, which seriously limits their applications. In this paper, Si(100)/Ta(100 nm)/NdxFe91-xB9(x = 14.5, 16.4, 18.2)/Ta (100 nm) films with thicknesses of 2-10 µm are prepared by magnetron sputtering. It is found that gradient annealing (GN) could help improve the magnetic anisotropy and texture of the micron-thickness film. When the Nd-Fe-B film thickness increases from 2 µm to 9 µm, its magnetic anisotropy and texture do not deteriorate. For the 9 µm Nd-Fe-B film, a high coercivity of 20.26 kOe and high magnetic anisotropy (remanence ratio Mr/Ms = 0.91) are achieved. An in-depth analysis of the elemental composition of the film along the thickness direction is conducted, and the presence of Nd aggregation layers at the interface between the Nd-Fe-B and the Ta layers is confirmed. The influence of thicknesses of the Ta buffer layer on the peeling of Nd-Fe-B micron-thickness films after high-temperature annealing is investigated, and it is found that increasing the thickness of the Ta buffer layer could effectively inhibit the peeling of Nd-Fe-B films. Our finding provides an effective way to modify the heat treatment peeling of Nd-Fe-B films. Our results are important for the development of Nd-Fe-B micron-scale films with high perpendicular anisotropy for applications in magnetic MEMS.

Long non-coding RNA and circular RNA and coding RNA profiling of plasma exosomes of osteosarcoma by RNA seq.

Osteosarcoma (OS) is a primary bone tumor with high malignancy and the mechanism of hematogenous metastasis in OS is still not clear. The plasma exosomes derived from osteosarcoma play a key role in the process of tumor metastasis. Here, we established RNA-seq dataset for lncRNAs, circRNAs and mRNAs in plasma exosomes from 10 OS patients and 5 healthy donors. A total of 329.52 Gb of clean data was obtained. Besides, 1754 lincRNAs, 7096 known and 1935 new circRNA was identified. Finally, gene expression profiles and differentially expressed genes (DEGs) were analyzed among these 15 samples. There were 331 DEGs of mRNA, 132 of lincRNA and 489 of circRNA was obtained, respectively. This data set provides a significant resource for relevant researchers to excavate potential dysregulated lncRNAs, circRNAs and mRNAs of plasma exosomes in OS versus normal conditions.

Interaction gene set between osteoclasts and regulatory CD4+ T cells can accurately predict the prognosis of patients with osteosarcoma.

Osteoclasts (OCs) and regulatory CD4+ T cells (CD4+ Tregs) are important components in the tumor microenvironment (TME) of osteosarcoma. In this study, we collected six osteosarcoma samples from our previous study (GSE162454). We also integrated a public database (GSE152048), which included single cell sequencing data of 11 osteosarcoma patients. We obtained 138,192 cells and then successfully identified OCs and CD4+ Tregs. Based on the interaction gene set between OCs and CD4+ Tregs, patients from GSE21257 were distinguished into two clusters by consensus clustering analysis. Both the tumor immune microenvironment and survival prognosis between the two clusters were significantly different. Subsequently, five model genes were identified by protein-protein interaction network based on differentially upregulated genes of cluster 2. Quantitative RT-PCR was used to detect their expression in human osteoblast and osteosarcoma cells. A prognostic model was successfully established using these five genes. Kaplan-Meier survival analysis found that patients in the high-risk group had worse survival (p = 0.029). Therefore, our study first found that cell-cell communication between OCs and CD4+ Tregs significantly alters TME and is connected to poor prognosis of OS. The model we constructed can accurately predict prognosis for osteosarcoma patients.

A novel molecular signature for predicting prognosis and immunotherapy response in osteosarcoma based on tumor-infiltrating cell marker genes.

Background: Tumor infiltrating lymphocytes (TILs), the main component in the tumor microenvironment, play a critical role in the antitumor immune response. Few studies have developed a prognostic model based on TILs in osteosarcoma. Methods: ScRNA-seq data was obtained from our previous research and bulk RNA transcriptome data was from TARGET database. WGCNA was used to obtain the immune-related gene modules. Subsequently, we applied LASSO regression analysis and SVM algorithm to construct a prognostic model based on TILs marker genes. What's more, the prognostic model was verified by external datasets and experiment in vitro. Results: Eleven cell clusters and 2044 TILs marker genes were identified. WGCNA results showed that 545 TILs marker genes were the most strongly related with immune. Subsequently, a risk model including 5 genes was developed. We found that the survival rate was higher in the low-risk group and the risk model could be used as an independent prognostic factor. Meanwhile, high-risk patients had a lower abundance of immune cell infiltration and many immune checkpoint genes were highly expressed in the low-risk group. The prognostic model was also demonstrated to be a good predictive capacity in external datasets. The result of RT-qPCR indicated that these 5 genes have differential expression which accorded with the predicting outcomes. Conclusions: This study developed a new molecular signature based on TILs marker genes, which is very effective in predicting OS prognosis and immunotherapy response.

Platelet to lymphocyte ratio was a risk factor in Perthes disease.

The study was aimed to determine the relationship between PLR (platelet to lymphocyte ratio) and the lateral pillar classification of Perthes disease, and to provide an alternative index for clinical diagnosis. In addition, the association of the PLR with the necrosis stage of Perthes disease was also explored. This was a retrospective study. 74 children with Perthes disease and 60 children in the healthy control group without femoral head necrosis in our hospital from 2012 to 2021 were collected. The general data and clinical parameters were collected from the hospital information system. The modified herring lateral pillar classification was collected for the fragmentation stage case group and the PLR, NLR (neutrophil to lymphocyte ratio), LMR (lymphocyte to monocyte ratio) and PNR (platelet to neutrophil ratio) were calculated. The cases were divided into four groups, herring A and B were group I, herring B/C and C were group II, the healthy control group was group III, and the necrosis stage was group IV. The hematological indexes (NLR, PLR, LMR, PNR) of children at different stages were statistically analyzed. Group I consisted of 36 patients, with an average age of 7.4 ± 2.0 years (3-11 years). Group II consisted of 23 patients, with an average age of 7.4 ± 1.9 years (4-12 years). Group III consisted of 60 patients, with a mean age of 7.4 ± 2.7 years (4-13 years). Group IV consisted of 15 patients, with an average age of 6.4 ± 1.7 years (3-10 years). The average values of PLR in groups I, II, III and IV were 131.98 ± 47.44, 122.19 ± 37.88, 102.46 ± 30.68 and 128.90 ± 28.11, respectively. It's worth noting that there was statistically significant difference among groups I, II and III (P = 0.003). The optimal threshold of PLR was 130.25, the sensitivity was 45.8% and the specificity was 85%. PLR was also significantly different between groups III and group IV. PLR was higher in Herring A and B classifications than in Herring B/C and C classifications. PLR had certain diagnostic value in both the necrosis stage and fragmentation stage as a risk factor.

Isosinensetin alleviates estrogen deficiency-induced osteoporosis via suppressing ROS-mediated NF-κB/MAPK signaling pathways.

The formation of osteoclasts and their hyperactive bone resorption are related to the aggregation of intracellular reactive oxygen species (ROS). Flavonoids, derived from plant active ingredients, can alleviate the symptoms of osteoporosis (OP). Isosinensetin (Iss) is a flavonoid with antioxidant effects obtained mainly from citrus fruits, and its effect on osteoclastogenesis has not been reported. In this study, we investigated the antioxidant activity of Iss on osteoclast differentiation and function, as well as the therapeutic impact of Iss on OP. We found that Iss inhibited osteoclastogenesis and suppressed the bone resorption function of osteoclasts. Additionally, Iss reduced receptor activator of nuclear factor-κB ligand (RANKL)-induced intracellular ROS. Using quantitative real-time polymerase chain reaction and western blot, we further found that Iss inhibited osteoclast-specific genes and related proteins, while promoting the expression of antioxidant enzyme-related genes and proteins. Mechanistically, Iss reduces intracellular ROS by activating nuclear factor-erythroid 2-related factor 2 (Nrf2) and its related antioxidant enzymes and inhibits the downstream nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways of ROS, which in turn inhibits nuclear factor of activated T cells 1 (NFATc1), and ultimately inhibits osteoclastogenesis. In vivo, by micro-computed tomography (Micro-CT) assay and histological analyses, we found that Iss could reduce bone loss in ovariectomized (OVX) mice. Therefore, Iss has the potential as an OP preventative and therapeutic drug option.

Trends of denosumab-related publications in web of science.

Denosumab is a human monoclonal antibody that targets nuclear factor-kappa B ligand and is highly effective in blocking bone resorption. Bibliometrics can intuitively show the research development process, research status, research hotspots and development trend of a certain topic for researchers. This study assessed the course of research and development for denosumab in terms of publications over the past 2 decades. Web of Science databases were searched to identify publications related to research on denosumab from January 1, 2005 to December 31, 2022. The VOS Viewer software (version 1.6.17) and Bibliometrix package in R (version 4.1.3) were used in this study. There were 5119 denosumab-related publications during this period. The total number of citations of denosumab-related publications reached 94917. The most articles were published in the field of Endocrinology Metabolism. As an international language, English remains the most popular language for writing papers. Five of the top ten institutions originated in the USA. Through the VOS Viewer analysis, we found that the relationships between Amgen Inc. with its collaborations were grouped into 4 clusters, the USA was the mainland for research and development on denosumab, closely collaborating with many other countries, such as Canada, Japan, England, and China. Wagman RB from USA was the most prolific author with 119 publications. The journal with the most publications was Osteoporosis International (481 publications). The most cited article was "Denosumab for Prevention of Fractures in Postmenopausal Women with Osteoporosis" with 2053 citations. The clinical trial comprised 6 of the 10 most frequently cited publications, and the rest consisted of reviews. The most frequent keywords for publications since January 1, 2014 were "prevention" and "management," indicating that a number of prevention and management measures have been developed to regulate the use of denosumab in treating osteoporosis. Our research provided a comprehensive review of denosumab-related publications, suggesting that the development of denosumab is a long process and numerous clinical trials have been conducted before applications in clinical settings.

Analysis of scRNA-seq and bulk RNA-seq demonstrates the effects of EVI2B or CD361 on CD8+ T cells in osteosarcoma.

Osteosarcoma (OS) is a common primary malignant tumor of the bone in children and adolescents. The five-year survival rate is estimated to be ~70% based on the currently available treatment modalities. It is well known that tumor-infiltrating immune cells (TIICs) that are the most important components in the tumor microenvironment can exert a killing effect on tumor cells. Therefore, in the present study, 85 RNA-sequencing OS samples were categorized into high- and low-immune score groups with ESTIAMATE. Based on the immune score groups, 474 differentially expressed genes (DEGs) were acquired using the LIMMA package of R language. Subsequently, 86 DEGs were taken through univariate COX regression analysis, of which 14 were screened out by least absolute shrinkage and selection operator regression analysis. Furthermore, multivariate COX regression analysis was performed to obtain 4 DEGs. Finally, ecotropic virus integration site 2B (EVI2B) or CD361 gene was screened out via Kaplan-Meier analysis. In addition, CIBERSORT algorithm was used to evaluate the proportion of 22 kinds of TIICs in OS. Correlation analysis revealed that the high expression level of EVI2B can elevate the infiltrated proportion of CD8+ T cells. Moreover, analysis of single cell RNA-sequencing transcriptome datasets and immunohistochemical staining uncovered that EVI2B was mainly expressed on CD8+ T cells and that EVI2B could promote the expression of granzyme A and K of CD8+ T cells to exhibit a potent killing effect on tumor cells. Therefore, EVI2B was identified as a protective immune-related gene and contributed to good prognosis in OS patients.

UPLC/Q-TOF-MS-based Metabolomics Study of the Antiosteoporosis Effects of Vaccarin in Ovariectomized Mice.

Osteoporosis is a systemic and metabolic bone disease that usually occurs in postmenopausal women, which mainly manifests as bone loss and increased bone fragility that both facilitate fracture. However, few drugs for osteoporosis have shown good efficacy and limited side effects. Vaccarin has demonstrated its antiosteoporosis effects by inhibiting the formation and osteolytic activities of osteoclasts in our previous investigation. In this study, multivariate statistical analysis and ultrahigh-performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry were used to analyze the serum metabolites of ovariectomized mice treated with or without vaccarin. As a result, 9 serum metabolites were identified as biomarkers. The metabolic levels of 3 crucial biomarkers, namely, lysophosphatidylcholine [22 : 6, (4Z, 7Z, 10Z, 13Z, 16Z, 19Z)], 1-linoleoylglycerophosphocholine and 1-palmitoyl-Sn-glycero-3-phosphocholine, that were correlated with glycerophospholipid metabolism increased and then decreased significantly after vaccarin treatment. Molecular docking analysis and osteoclasts differentiation experiment further revealed that vaccarin may bind with phospholipase A2 and downregulated its activity to reduce the osteoclastogenesis. Therefore, the occurrence of osteoporosis is closely related with glycerophospholipid metabolism disorders, and vaccarin exerts antiosteoporosis effects by reducing the levels of glycerophospholipid metabolites.

Corrigendum: Single-cell transcriptomics reveals the complexity of the tumor microenvironment of treatment-naive osteosarcoma.

[This corrects the article DOI: 10.3389/fonc.2021.709210.].

Construction of a transcription factor-miRNA-mRNA interactive network elucidates underlying pathogenesis for osteosarcoma and validation by qRT-PCR.

PURPOSE: Osteosarcoma is characterized by features of rapid growth and early metastasis with a poor prognosis. The aim of our research is to investigate the potential transcription factor (TF)-miRNA-mRNA regulatory mechanism in osteosarcoma utilizing bioinformatics methods and validate by qRT-PCR. METHODS: The microRNA (miRNA) expression profiling datasets (GSE28423 and GSE65071) and mRNA expression profiling dataset GSE33382 were collected from the Gene Expression Omnibus (GEO) database. Differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs) were screened using the limma package. Then, the TransmiR v2.0, miRDB, and Targetscan 7.2 database were applied for the acquisition of TF-miRNA and miRNA-mRNA interaction relationships, respectively. Finally, we built a TF-miRNA-mRNA interactive network. Furthermore, survival analysis was performed to identify sub-network with prognostic value and validate through qRT-PCR. RESULTS: Eight overlapping DEMs and 682 DEGs were identified. Based on bioinformatics methods, 30 TF-miRNA interaction pairs and 25 miRNA-mRNA interaction pairs were screened. Finally, we constructed a TF-miRNA-mRNA regulatory network. Furthermore, laminin subunit gamma 1 (LAMC1) and thrombospondin-1 (THBS1), which involved in the network, were determined to have prognostic value and the corresponding subnetwork was identified. qRT-PCR results showed that LAMC1 mRNA expression was higher in osteosarcoma cells. CONCLUSION: Based on the survival analysis, a TF-miRNA-mRNA sub-network, that is TFs (SPI1, HEY1, and CEBPB)-hsa-miR-338-3p-target genes (LAMC1 and THBS1) was established. In conclusion, the construction of a potential TF-related regulatory network will help elucidate the underlying pathological mechanisms of osteosarcoma, and may provide novel insights for the diagnosis and treatment of osteosarcoma.