Nanoparticles-encapsulated doxorubicin alleviates drug resistance of osteosarcoma via inducing ferroptosis.

To determine the effects of polymeric nanoparticle for doxorubicin (Dox) delivery and treatment of drug-resistant Osteosarcoma (OS) cells. Methoxy-polyethylene glycol amino (mPEG-NH2) and platinum bio-mimetic polycaprolactone-cysteine (PtBMLC) were crosslinked to obtain glutathione (GSH)-responsive mPEG-NH2-PtBMLC polymer to encapsulate Dox (named as Nano-Dox). The particle size and zeta potential of the nanoparticles were measured, and internalization of Dox by OS cells was observed. After treatment with Nano-Dox, cell proliferation was determined by cell counting kit 8 (CCK-8) and colony formation assay. Cell migration and invasion were determined by Transwell assay. Cell cycle arrest was assessed by flow cytometry. The induction of ferroptosis was analyzed by abnormal accumulation of total iron, Fe2+. Nano-Dox exhibited a stronger localization in OS cells (p < 0.01). Nano-Dox induced more significant suppression of drug-resistant OS cell growth (p < 0.01), migration (p < 0.01), and invasion (p < 0.01), compared with the single Dox treatment group, along with decreased expression of N-cadherin, Snail, and Vimentin, suggesting impaired cancer migration and invasion. The treatment with Nano-Dox induced notable cell cycle arrest at G0/G1 phase (p < 0.01) and accumulation of iron, Fe2+, and MDA (p < 0.01), as well as suppressed the protein levels of glutathione peroxidase 4 (GPX4) and SLC7A11. Administration of ferroptosis inhibitor (Fer-1) reversed the anti-proliferation effects of Nano-Dox (p < 0.01). The Dox delivered by the polymeric nanoparticle system notably enhanced its effects on suppressing the growth, migration, and invasion of drug-resistant OS cells via inducing ferroptosis. The application of environment response polymer enhanced the delivery of Dox and the therapeutic effects on OS.

Inflammatory and nutritional markers predict the risk of post-operative delirium in elderly patients following total hip arthroplasty.

Objectives: This study intended to explore whether albumin-associated inflammatory and nutritional markers could predict post-operative delirium (POD) in older patients after total hip arthroplasty (THA). In addition, we established a nomogram model for POD prediction. Methods: Totally, 254 elderly cases who received THA were included. Clinical and laboratory data of these patients were retrospectively collected. Albumin-associated inflammatory and nutritional markers included neutrophil-to-albumin ratio (NAR), CRP-to-albumin ratio (CAR), prognostic nutritional index (PNI), and systemic inflammation score (SIS). The LASSO, univariate and multivariate logistic regression analyses were utilized to screen risk factors. A nomogram model was developed according to the results of multivariate regression analyses. Results: Among 254 patients, 49 cases had POD with an incidence of 19.3%. LASSO regression and multivariate logistic analyses suggested that preoperative NAR, preoperative PNI, preoperative SIS, and age >75 years were risk factors for POD. A nomogram model was developed according to the results of multivariate logistic analyses. The calibration curve suggested that the predicted probability of this nomogram model was in good line with the actual probability. The DCA showed that this nomogram model had net benefits for the prediction of POD for elderly patients following THA. Conclusion: Albumin-associated inflammatory and nutritional markers including NAR, PNI, and SIS could predict POD in elderly patients following THA.

Corrigendum: The role of NR4A1 in the pathophysiology of osteosarcoma: A comprehensive bioinformatics analysis of the single-cell RNA sequencing dataset.

[This corrects the article DOI: 10.3389/fonc.2022.879288.].

The Role of NR4A1 in the Pathophysiology of Osteosarcoma: A Comprehensive Bioinformatics Analysis of the Single-Cell RNA Sequencing Dataset.

Osteosarcoma is a kind of aggressive human malignancy, and the prognosis of the patients with osteosarcoma remains low. Studies have demonstrated that the tumor microenvironment plays a key role in regulating osteosarcoma progression. Recent studies have also shown that scRNA-seq plays an essential role in understanding the tumor heterogeneity and distinct subpopulations of tumors. In order to further understand the scRNA-seq data of osteosarcoma tissues, the present study further analyzed the scRNA-seq dataset (GSE152048) and explored the potential role of nuclear receptor-related genes in the pathophysiology of osteosarcoma. In our analysis, we identified 11 cell types in all the osteosarcoma tissues and nuclear receptors (NRs) were distributed in all types of cells. Further stratification analysis showed that NRs were mainly detected in "TIL" and "Osteoblastic" of the metastasis osteosarcoma, in "TIL", "Myoblast", "Endothelial", and "Myeloid" of the primary osteosarcoma, and in "Chondroblastic", "Osteoblast", and "Pericyte" of the recurrent osteosarcoma. The NRs were also differentially expressed in different cell types among the metastasis, primary, and recurrent osteosarcoma. Furthermore, several NRs such as NR4A2, NR4A1, and NR3C1 have been found to be differentially expressed in most types of DEGs among metastasis, primary, and recurrent osteosarcoma. A high expression of NR4A1 in the osteosarcoma tissues was significantly correlated with a shorter 5-year overall survival of patients with osteosarcoma. On the other hand, there was no significant association between NR4A2 expression and the 5-year overall survival of patients with osteosarcoma. The expression of NR4A1 was significantly higher in the metastasis osteosarcoma tissues than in the primary osteosarcoma tissues as validated from GSE32981 and GSE154540. The expression of NR4A1 was significantly higher in osteosarcoma tissues from patients with poor chemosensitivity than that from patients with good chemosensitivity as validated from GSE154540. Further analysis of the scRNA-seq data revealed that the percentage of osteoblasts with a high NR4A1 expression was higher in the recurrent osteosarcoma tissues than that with a low NR4A1 expression. In conclusion, the present study may suggest that NR4A1 may be an important prognostic biomarker for osteosarcoma progression. However, further validation studies should be performed to confirm our findings.

FGF23 protects osteoblasts from dexamethasone-induced oxidative injury.

Dexamethasone (DEX) can exert a cytotoxic effect on cultured osteoblasts. The current study explored the potential osteoblast cytoprotective effect of fibroblast growth factor 23 (FGF23). In OB-6 human osteoblastic cells and primary murine osteoblasts, FGF23 induced phosphorylation of the receptor FGFR1 and activated the downstream Akt-S6K1 signaling. FGF23-induced FGFR1-Akt-S6K phosphorylation was largely inhibited by FGFR1 shRNA, but augmented with ectopic FGFR1 expression in OB-6 cells. FGF23 attenuated DEX-induced death and apoptosis in OB-6 cells and murine osteoblasts. Its cytoprotective effects were abolished by FGFR1 shRNA, Akt inhibition or Akt1 knockout. Conversely, forced activation of Akt inhibited DEX-induced cytotoxicity in OB-6 cells. Furthermore, FGF23 activated Akt downstream nuclear-factor-E2-related factor 2 (Nrf2) signaling to alleviate DEX-induced oxidative injury. On the contrary, Nrf2 shRNA or knockout almost reversed FGF23-induced osteoblast cytoprotection against DEX. Collectively, FGF23 activates FGFR1-Akt and Nrf2 signaling cascades to protect osteoblasts from DEX-induced oxidative injury and cell death.

CDH2 gene rs11564299 polymorphism is a risk factor for knee osteoarthritis in a Chinese population: a case-control study.

BACKGROUND: Cadherin-2 (CDH2) gene polymorphisms were reported to be associated with the induction and development of knee osteoarthritis (OA). METHODS: This case-control study was designed to explore the association between CDH2 gene rs11564299 polymorphism and the risk of knee OA in Chinese subjects. The polymorphism was genotyped by polymerase chain reaction and Sanger sequencing. RESULTS: G allele or GG genotype of CDH2 gene rs11564299 polymorphism was related to increased risk for knee OA in the Chinese Han population. Additionally, subgroup analyses indicated that the female, smoker, drinker, and BMI ≥ 25 kg/m2 groups showed increased risk for knee OA. Additionally, this polymorphism was associated with CRP and Kellgren-Lawrence grade. CONCLUSION: In summary, this current study reveals that CDH2 gene rs11564299 polymorphism is a risk factor for knee OA development in this Chinese population. The genotypes distribution differed significantly among OA patients and healthy controls and may be a useful tool in the evaluation of OA susceptibility in Chinese Han population.

miR-1285-3p is a potential prognostic marker in human osteosarcoma and functions as a tumor suppressor by targeting YAP1.

BACKGROUND: Despite the major advances in the treatment, the overall survival of osteosarcoma remains poor. MicroRNAs (miRNAs) are involved in tumorigenesis and progression though modulating their target genes. In the present study, the roles of miR-1285-3p in osteosarcoma was investigated. METHODS: Microarray profiling was applied to distinguish the up and down regulated microRNAs in osteosarcoma. Quantitative real-time PCR (qRT-PCR) assay was performed to detect the expression of miR-1285-3p and YAP1 expression. MTT and transwell assays were carried out to determine the cells proliferation and invasion respectively. Moreover, dual luciferase reporter assay was performed to evaluate the binding efficiency between miR-1285-3p and the 3'UTR of YAP1. RESULTS: MiR-1285-3p was down regulated in osteosarcoma tissues and cell lines and the reduction of miR-1285-3p expression predicted a poor overall survival of osteosarcoma patients. Ectopic expression of miR-1285-3p inhibited osteosarcoma cell proliferation, colony formation and invasion. In addition, YAP1 was further demonstrated as a direct target of miR-1285-3p. Moreover, overexpression of YAP1 reversed the inhibitory effects of miR-1285-3p on osteosarcoma cells proliferation and invasion. CONCLUSIONS: MiR-1285-3p which was low expressed in osteosarcoma inhibited the proliferation and invasion of osteosarcoma cells via direct targeting YAP1. These results suggested that miR-1285-3p might be a potential therapeutic targets and biomarker in osteosarcoma.

SP1-mediated upregulation of lncRNA ILF3-AS1 functions a ceRNA for miR-212 to contribute to osteosarcoma progression via modulation of SOX5.

Long noncoding RNA ILF3-AS1 (ILF3-AS1) has been reported to be abnormally expressed in several tumors. However, its expression pattern and function in osteosarcoma have not been investigated. In this study, we showed that ILF3-AS1 expression was significantly up-regulated in both osteosarcoma tissues and cell lines. We first reported that ILF3-AS1 upregulation was induced by nuclear transcription factor SP1. Clinical assays revealed that higher expression of ILF3-AS1 was associated with advanced clinical stage, distant metastasis and shorter overall survival. in multivariate analysis, ILF3-AS1 expression level was found to be an independent prognostic factor for osteosarcoma patients. Functional investigations showed that knockdown of ILF3-AS1 suppressed the proliferation, migration and invasion of osteosarcoma cells, and promoted apoptosis. Bioinformatic software predicted that miR-212 both targeted the 3'-UTR of ILF3-AS1 and SOX5, which was confirmed using luciferase reporter assay, RT-PCR and Western blot. Taken together, ILF3-AS1 displayed its tumor-promotive roles in the progression of osteosarcoma through miR-212/SOX5 axis. Our findings help to elucidate the tumorigenesis of osteosarcoma, and future study will provide a novel therapeutic target for osteosarcoma.

Association between ADIPOQ gene variants and knee osteoarthritis in a Chinese population.

A study from Thailand showed no significant association between the adiponectin (ADIPOQ) gene rs1501299 polymorphism and knee osteoarthritis (OA) risk. To investigate this association in a Chinese population, we conducted this case-control study involving 372 knee OA patients and 453 controls. Genotyping via standard PCR and restriction fragment length polymorphism (PCR-RFLP) showed that TT genotype (TT vs. GG: adjusted odds ratio (OR) (95% confidence interval (CI)) = 1.70 (1.01-2.86)) or T allele (T vs. G: adjusted OR (95% CI) = 1.26 (1.02-1.56)) of ADIPOQ gene rs1501299 polymorphism significantly increased the risk of knee OA. Significant associations were also observed in subgroups ≥55 years (TT vs. GG: adjusted OR (95% CI) = 2.21 (1.00-4.86)) and body mass index (BMI) < 25 kg/m2 (TT+GT vs. GG: adjusted OR (95% CI) = 1.53 (1.03-2.29)), but not in the subgroup analysis of sex. In conclusion, the ADIPOQ gene rs1501299 polymorphism intensifies the risk of knee OA in this Chinese Han population. Nevertheless, further studies with larger sample sizes in other populations are warranted to verify this finding.

OPN gene locus is associated with the risk of knee osteoarthritis: a case-control study.

Background/aims: Studies have demonstrated that osteopontin (OPN) was associated with the severity and development of knee osteoarthritis (OA). Methods: The purpose of this case-control study was to investigate the association between OPN gene rs11730582 polymorphism and knee OA risk in a Chinese population. Genotyping was analyzed using standard PCR and restriction fragment length polymorphism (PCR-RFLP). Results: The present study found that C allele or CC genotype of OPN gene rs11730582 polymorphism was related to decreased risk for knee OA. Furthermore, positive associations were obtained amongst the females, and body mass index (BMI) < 25 kg/m2 groups. Conclusions: To sum up, the present study reveals that OPN gene rs11730582 polymorphism decreases the risk of knee OA in Chinese Han population.

Logistic regression analysis for the identification of the metastasis-associated signaling pathways of osteosarcoma.

Osteosarcoma (OS) is the most common histological type of primary bone cancer. The present study was designed to identify the key genes and signaling pathways involved in the metastasis of OS. Microarray data of GSE39055 were downloaded from the Gene Expression Omnibus database, which included 19 OS biopsy specimens before metastasis (control group) and 18 OS biopsy specimens after metastasis (case group). After the differentially expressed genes (DEGs) were identified using the Linear Models for Microarray Analysis package, hierarchical clustering analysis and unsupervised clustering analysis were performed separately, using orange software and the self-organization map method. Based upon the Database for Annotation, Visualization and Integrated Discovery tool and Cytoscape software, enrichment analysis and protein-protein interaction (PPI) network analysis were conducted, respectively. After function deviation scores were calculated for the significantly enriched terms, hierarchical clustering analysis was performed using Cluster 3.0 software. Furthermore, logistic regression analysis was used to identify the terms that were significantly different. Those terms that were significantly different were validated using other independent datasets. There were 840 DEGs in the case group. There were various interactions in the PPI network [including intercellular adhesion molecule-1 (ICAM1), transforming growth factor ß1 (TGFB1), TGFB1-platelet-derived growth factor subunit B (PDGFB) and PDGFB-platelet­derived growth factor receptor-ß (PDGFRB)]. Regulation of cell migration, nucleotide excision repair, the Wnt signaling pathway and cell migration were identified as the terms that were significantly different. ICAM1, PDGFB, PDGFRB and TGFB1 were identified to be enriched in cell migration and regulation of cell migration. Nucleotide excision repair and the Wnt signaling pathway were the metastasis-associated pathways of OS. In addition, ICAM1, PDGFB, PDGFRB and TGFB1, which were involved in cell migration and regulation of cell migration may affect the metastasis of OS.

Targeted activation of AMPK by GSK621 ameliorates H2O2-induced damages in osteoblasts.

GSK621 is a novel AMP-activated protein kinase (AMPK) activator. This study tested its potential cytoprotective effect in hydrogen peroxide (H2O2)-treated osteoblasts. In cultured MC3T3-E1 osteoblastic cells and primary murine osteoblasts, GSK621 significantly attenuated H2O2-induced cell death and apoptosis. AMPK activation was required for GSK621-induced osteoblast cytoprotection. Inhibition of AMPK, by AMPKα1 T172A mutation or shRNA silence, almost completely blocked GSK621-induced osteoblast cytoprotection. Reversely, introduction of a constitutively-active AMPKα1 (T172D) alleviated H2O2 injuries in MC3T3-E1 cells. Further, GSK621 increased nicotinamide adenine dinucleotide phosphate (NADPH) content in osteoblasts to inhibit H2O2-induced reactive oxygen species (ROS) production. Meanwhile, GSK621 activated cytoprotective autophagy in the osteoblasts. On the other hand, pharmacological inhibition of autophagy alleviated GSK621-mediated osteoblast cytoprotection against H2O2. These results suggest that targeted activation of AMPK by GSK621 ameliorates H2O2-induced osteoblast cell injuries.

TWEAK/Fn14 signaling: a promising target in intervertebral disc degeneration.

Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a potent chemoattractant cytokine with various biological functions, such as stimulation of angiogenesis, induction of proinflammatory cytokines, regulation of cellular proliferation and apoptosis. Therefore, it has also been implicated in several pathological processes, from cancer to inflammatory diseases. Remarkably, TWEAK and its receptors, fibroblast growth factor inducible 14 (Fn14), are also present in intervertebral disc (IVD) tissue, where they play a role in the pathogenesis of IVD degeneration. The interaction of TWEAK with Fn14 is involved in physiological and pathological activities of IVD degeneration patients, which includes apoptosis of endplate chondrocytes, extracellular matrix degradation, reduction in proteoglycan synthesis and so on. The blockade of this interaction results in suppressing over-production of proinflammatory factors and cell death in in vivo or in vitro experiments, suggesting that TWEAK/Fn14 signaling may be therapeutically relevant in IVD degeneration, and the targeting of TWEAK or Fn14 has been proposed as a potential therapeutic approach for autoimmune diseases such as Rheumatoid arthritis (RA). In this article, we discuss the biological features of TWEAK/Fn14 signaling and summarize recent advances in our understanding of the role of TWEAK/Fn14 signaling in the pathogenesis and treatment of IVD degeneration. We think that the blockade of TWEAK/Fn14 signaling may be a promising therapeutic strategy for IVD degeneration in the near future.

Tibial Tuberosity Avulsion Fracture and Open Proximal Tibial Fracture in an Adult: A Case Report and Literature Review.

A displaced tibial tuberosity avulsion fracture associated with an open extra-articular proximal tibial diaphyseal fracture is an uncommon fracture pattern. This case report describes the successful management of such a fracture pattern in a 45-year old male using an open reduction and lag screw fixation of the tuberosity with a minimally invasive reduction and plate fixation of the proximal tibial diaphyseal fracture. A literature search was done to determine the expected clinical outcome of this fracture pattern. This is the first reported adult case of an avulsion fractures of the tibial tuberosity associated with an open proximal tibial diaphyseal fracture successfully treated by an anatomical reduction and fixation of the avulsion fracture of the tibial tuberosity combined with minimally invasive percutaneous plate osteosynthesis of the proximal tibial diaphyseal fractures.

Restoration of femoral offset, rotation centers, limbs length equality of Chinese total hip arthroplasty patients.

OBJECTIVE: To explore the restoration of femoral offset, rotation centers, limbs length equality of Chinese total hip arthroplasty patients with careful preoperative surgical planning, the appropriate prosthesis and skillful manipulation combined with a variety of verification tests during the operation. METHODS: There were 92 hips (from 92 patients) surgery was performed by the same surgeon using the posterlateral approach by careful preoperative surgical planning. Appropriate prosthesis was chosen determining the reasonable femur osteotomy location, skillful manipulation and paying attention to every detail combined with a variety of verification tests and preoperative measurements during the operation. We evaluated the offset and rotation centers of the healthy (not performed) side and the operated side, the preoperative and postoperative limbs length discrepancy and analyzed the change of femoral offset, rotation centers and limbs length discrepancy of THA patients by self-control. RESULTS: We found that the preoperative and postoperative femoral offset was basically not changed, the postoperative rotation centers had a tendency to the medial and inferior of the original rotation centers, the limbs length discrepancy and Harris Hip Score (HHS) were improved much more than before. CONCLUSIONS: Careful preoperative surgical planning, the appropriate prosthesis and skillful manipulation combined with a variety of verification tests during the operation is significantly correlated to the remarkable radiological and clinical results of THA patients.

Repair of meniscal defect using an induced myoblast-loaded polyglycolic acid mesh in a canine model.

Defects of the meniscus greatly alter knee function and predispose the joint to degenerative changes. The purpose of this study was to test a recently developed cell-scaffold combination for the repair of a critical-size defect in the canine medial meniscus. A bilateral, complete resection of the anterior horn of the medial meniscus was performed in 18 Beagle canines. A PLGA scaffold was implanted into the defect of one knee of 6 canines and the contralateral defect was left untreated. Scaffolds loaded with autologous myoblasts and cultured in a chondrogenic medium for 14 days were implanted in a second series of 12 canines. Empty scaffolds were implanted in the contralateral knees. Menisci were harvested at 12 weeks. Untreated defects had a muted fibrous healing response. Defects treated with cell-free implants also showed predominantly fibrous tissue, whereas fibrocartilage was present in several scaffolds. The thickness of the repair tissue after treatment with cell-free scaffolds was significantly greater compared to the controls (p<0.05). Pre-cultured implants integrated with the host tissue, and 9 of 12 contained meniscus-like fibrocartilage when compared to 2 of the 12 controls (p<0.05). The thickness of the pre-cultured implant repair tissue was greater compared to the controls (p<0.05). This study demonstrates the repair of a critical size meniscal defect using a stem cell and scaffold-based tissue engineering approach.