Discovery of a Highly Potent PROTAC Degrader of p300/CBP Proteins for the Treatment of Enzalutamide-Resistant Prostate Cancer.

Prostate cancer therapies against androgen receptor (AR) eventually develop lethal resistance; thus, exploring new therapeutic approaches is urgent for prostate cancer treatment. Acetyltransferase p300/CBP are key coactivators for AR-mediated transcription and represent promising therapeutic targets to inhibit AR activity in prostate cancer. We describe the design synthesis and evaluation of a new class of p300/CBP PROTAC degraders. We identified an excellent p300/CBP degrader MJP6412, which effectively induced degradation of p300/CBP proteins, downregulated AR target genes, and inhibited cell growth of human prostate cancer cell lines and enzalutamide-resistant cells with IC50 even at nanomolar concentrations. Furthermore, MJP6412 demonstrated significant inhibition of tumor growth in a VCaP xenograft model. Collectively, MJP6412 is a promising lead compound for the treatment of prostate cancer, especially enzalutamide-resistant prostate cancer.

Arthroscopic Transtibial Pullout Repair and Tibial Condylar Valgus Osteotomy for Medial Meniscus Posterior Root Tear With Varus Knee.

As an important structure for maintaining the hoop tension of the medial meniscus of the knee joint, the posterior root is receiving increasing attention. Medial meniscus posterior root tear is an important reason for the occurrence, development, and kinematics changes of knee osteoarthritis. It is necessary to repair the posterior root of meniscus for restoring joint kinematics and improving clinical efficacy. This Technical Note reports a medial meniscus posterior root tear repair technique using arthroscopic transtibial pullout repair (ATPR) combined with tibial condylar valgus osteotomy. The aim of this technique is to repair the posterior root of the medial meniscus while correcting the force line through osteotomy, opening the joint gap, improving the joint surface fit, providing a good mechanical environment for meniscus repair, thereby improving the healing rate of the posterior root of the meniscus and reducing the risk of retear. Although clinical evidence is currently limited, we believe that this technology may have more clinical advantages compared with ATPR alone or ATPR combined with high tibial osteotomy.

EFHD1 promotes osteosarcoma proliferation and drug resistance by inhibiting the opening of the mitochondrial membrane permeability transition pore (mPTP) by binding to ANT3.

Chemoresistance is the main obstacle in the clinical treatment of osteosarcoma (OS). In this study, we investigated the role of EF-hand domain-containing protein 1 (EFHD1) in OS chemotherapy resistance. We found that the expression of EFHD1 was highly correlated with the clinical outcome after chemotherapy. We overexpressed EFHD1 in 143B cells and found that it increased their resistance to cell death after drug treatment. Conversely, knockdown of EFHD1 in 143BR cells (a cisplatin-less-sensitive OS cell line derived from 143B cells) increased their sensitivity to treatment. Mechanistically, EFHD1 bound to adenine nucleotide translocase-3 (ANT3) and inhibited its conformational change, thereby inhibiting the opening of the mitochondrial membrane permeability transition pore (mPTP). This effect could maintain mitochondrial function, thereby favoring OS cell survival. The ANT3 conformational inhibitor carboxyatractyloside (CATR), which can promote mPTP opening, enhanced the chemosensitivity of EFHD1-overexpressing cells when combined with cisplatin. The ANT3 conformational inhibitor bongkrekic acid (BKA), which can inhibit mPTP opening, restored the resistance of EFHD1 knockdown cells. In conclusion, our results suggest that EFHD1-ANT3-mPTP might be a promising target for OS therapy in the future.

Erratum: ATF6 aggravates angiogenesis-osteogenesis coupling during ankylosing spondylitis by mediating FGF2 expression in chondrocytes.

[This corrects the article DOI: 10.1016/j.isci.2021.102791.].

Low expression of ZFP36L1 in osteosarcoma promotes lung metastasis by inhibiting the SDC4-TGF-ß signaling feedback loop.

ZFP36L1, which is a negative regulator of gene transcripts, has been proven to regulate the progression of several carcinomas. However, its role in sarcoma remains unknown. Here, by using data analyses and in vivo experiments, we found that ZFP36L1 inhibited the lung metastasis of osteosarcoma (OS). Knockdown of ZFP36L1 promoted OS cell migration by activating TGF-ß signaling and increasing SDC4 expression. Intriguingly, we observed a positive feedback loop between SDC4 and TGF-ß signaling. SDC4 protected TGFBR3 from matrix metalloproteinase (MMP)-mediated cleavage and therefore relieved the inhibition of TGF-ß signaling by soluble TGFBR3, while TGF-ß signaling positively regulated SDC4 transcription. We also proved that ZFP36L1 regulated SDC4 mRNA decay through adenylate-uridylate (AU)-rich elements (AREs) in its 3'UTR. Furthermore, treatment with SB431542 (a TGF-ß receptor kinase inhibitor) and MK2 inhibitor III (a MAPKAPK2 inhibitor that increases the ability of ZFP36L1 to degrade mRNA) dramatically inhibited OS lung metastasis, suggesting a promising therapeutic approach for the treatment of OS lung metastasis.

SIRPA enhances osteosarcoma metastasis by stabilizing SP1 and promoting SLC7A3-mediated arginine uptake.

The function of signal regulatory protein alpha (SIRPA) has been well studied in macrophages and dendritic cells, but relatively less in tumors. Notably, SIRPA is upregulated in osteosarcoma tissues, particularly in metastatic tissues, and is associated with unfavorable clinical outcomes. Knockdown of SIRPA impaired OS cell migration by decreasing specificity protein 1 (SP1) stability and arginine uptake. Importantly, SIRPA phosphorylated SP1 at threonine 278 (Thr278) through extracellular signal-regulated kinase (ERK) activation to protect SP1 from proteasomal degradation. In addition, SP1 increased solute carrier family 7 member 3 (SLC7A3) expression by binding to the SLC7A3 promoter and increased the capability of arginine uptake, thereby facilitating OS cell migration. More interestingly, arginine promoted the stability of SP1 in an ERK-independent manner and thus formed the "SP1 stabilization circle". Combined treatment with the anti-SIRPA antibody and arginase, which blocked the circle, impaired tumor metastasis in mice bearing xenografts formed from SIRPA-overexpressing cells. In summary, our study demonstrates that the upregulation of SIRPA promotes OS metastasis via the "SP1 stabilization circle" and SLC7A3-mediated arginine uptake, which might serve as a target for OS treatment.

Alpinetin alleviates osteoporosis by promoting osteogenic differentiation in BMSCs by triggering autophagy via PKA/mTOR/ULK1 signaling.

Osteoporosis, a systemic bone disease that is characterized by a reduction in bone mass and destruction of bone microstructure, is becoming a serious problem worldwide. Bone marrow mesenchymal stem cells (BMSCs) can differentiate into bone-forming osteoblasts, and play an important role in maintaining homeostasis of bone metabolism, thus being a potential therapeutic target for osteoporosis. Although the phytochemical alpinetin (APT) has been reported to possess a variety of pharmacological activities, it is still unclear whether APT can influence the osteogenic differentiation of on BMSCs and if it can improve osteoporosis. In this study, we found that APT treatment was able to enhance osteogenic differentiation levels of human BMSCs in vitro and mouse ones in vivo as revealed by multiple osteogenic markers including increased alkaline phosphatase activity and osteocalcin expression. Mechanistically, the protein kinase A (PKA)/mTOR/ULK1 signaling was involved in the action of APT to enhance the osteogenic differentiation of BMSCs. In addition, oral administration of APT significantly mitigated the bone loss in a dexamethasone-induced mouse model of osteoporosis through strengthening PKA signaling and autophagy. Altogether, these data demonstrate that APT promotes osteogenic differentiation in BMSCs by augmenting the PKA/mTOR/ULK1 autophagy signaling, highlighting its potential therapeutic application for treating osteoporotic diseases.

Individual Surgical Treatment of Stage IV Müller-Weiss Disease According to CT/MRI Examination: A Retrospective Study of 12 Cases.

Background: This study reported the individual surgical treatment of 12 cases with stage IV Müller-Weiss disease (MWD) according to CT/MRI examination. Methods: In total, 12 cases diagnosed with stage IV MWD in our hospital from 2015 to 2019 were included in the retrospective study. Relevant clinical outcomes were evaluated preoperatively and postoperatively. Results: The follow-up results showed satisfactory outcomes in all cases. All the cases were presented with tenderness and chronic pain on the midfoot dorsum, and three cases were also presented with tenderness and pain on the lateral side of the midfoot, in which calcaneal cuboid arthritis was revealed by CT/MRI. The American Orthopedic Foot and Ankle Society (AOFAS) scores elevated from 62.5 ± 6.8 (range: 53-74) preoperatively to 95.3 ± 7.2 (range: 73-100) postoperatively (P < 0.005). The Visual Analog Scale (VAS) scores declined from 4.2 ± 0.9 (range: 3-5.5) preoperatively to 0.5 ± 0.3 (range: 0-2) postoperatively (P < 0.001). On the weight-bearing lateral view of the foot, the Tomeno-Méary angle (TM lat) changed from -11.2 ± 4.2 (range: -17.2 to -2.8) degrees preoperatively to -2.4 ± 3.9 (range: -10.2 to 5.2) degrees postoperatively (P < 0.001). Conclusions: The fusion of the talus-navicular joint and the adjacent affected joint provide good clinical outcomes. The CT/MRI scans are helpful to identify the adjacent joint arthritis and provide indications for individual treatment for Stage IV MWD.

DAPK1 Interacts with the p38 Isoform MAPK14, Preventing Its Nuclear Translocation and Stimulation of Bone Marrow Adipogenesis.

Bone marrow (BM) adipose tissue (BMAT), a unique adipose depot, plays an important role in diseases such as osteoporosis and bone metastasis. Precise control of mesenchymal stem cell (MSC) differentiation is critical for BMAT formation and regeneration. Here, we show that death associated protein kinase 1 (DAPK1) negatively regulates BM adipogenesis in vitro and in vivo. Prx1creDapk1loxp/loxp mice showed more adipocytes in the femur than Dapk1loxp/loxp mice. Further mechanistic analyses revealed that DAPK1 inhibits p38 mitogen-activated protein kinase (MAPK) signaling in the nucleus by binding the p38 isoform MAPK14, decreasing p38 nuclear activity, which subsequently inhibits BM adipogenesis. The inhibitory effect of DAPK1 against MAPK14 was independent of its kinase activity. In addition, the decreased DAPK1 was observed in the BM-MSCs of ageing mice. Our results reveal a previously undescribed function for DAPK1 in the regulation of adipogenesis and may also reveal the underlying mechanism of BMAT formation in ageing.

ZIP10 drives osteosarcoma proliferation and chemoresistance through ITGA10-mediated activation of the PI3K/AKT pathway.

BACKGROUND: The zinc transporters Zrt- and Irt-related protein (ZIP/SLC39) are overexpressed in human tumors and correlate with poor prognosis; however, their contributions to carcinogenesis and chemoresistance in osteosarcoma (OS) remain unclear. METHODS: We collected 64 OS patient tissues with (n = 12) or without (n = 52) chemotherapy. The expression levels of ZIP10 were measured by immunohistochemistry and applied to prognostic analysis. ZIP10 was knocked down or overexpressed in OS cell lines to explore its effect on proliferation and chemoresistance. RNA sequencing, quantitative real-time PCR, and western blotting analysis were performed to explore ZIP10-regulated downstream target genes. A xenograft mouse model was established to evaluate the mechanisms by which ZIP10 modulates chemoresistance in OS cells. RESULTS: The expression of ZIP10 was significantly induced by chemotherapy and highly associated with the clinical outcomes of OS. Knockdown of ZIP10 suppressed OS cell proliferation and chemoresistance. In addition, ZIP10 promoted Zn content-induced cAMP-response element binding protein (CREB) phosphorylation and activation, which are required for integrin α10 (ITGA10) transcription and ITGA10-mediated PI3K/AKT pathway activation. Importantly, ITGA10 stimulated PI3K/AKT signaling but not the classical FAK or SRC pathway. Moreover, overexpression of ZIP10 promoted ITGA10 expression and conferred chemoresistance. Treatment with the CREB inhibitor 666-15 or the PI3K/AKT inhibitor GSK690693 impaired tumor chemoresistance in ZIP10-overexpressing cells. Finally, a xenograft mouse model established by subcutaneous injection of 143B cells confirmed that ZIP10 mediates chemotherapy resistance in OS cells via the ZIP10-ITGA10-PI3K/AKT axis. CONCLUSIONS: We demonstrate that ZIP10 drives OS proliferation and chemoresistance through ITGA10-mediated activation of the PI3K/AKT pathway, which might serve as a target for OS treatment.

Effects of long-term culture on the biological characteristics and RNA profiles of human bone-marrow-derived mesenchymal stem cells.

Expansion in vitro prior to mesenchymal stem cells (MSCs) application is a necessary process. Functional and genomic stability has a crucial role in stem-cell-based therapies. However, the exact expression and co-expressed profiles of coding and non-coding RNAs in human bone marrow (BM)-MSCs in vitro aging are still lacking. In the present studies, the change of morphology, immunophenotype, and capacity of proliferation, differentiation, and immunoregulation of MSCs at passage (P) 4, P6, P8, P10, and P12 were investigated. RNA sequencing identified that 439 mRNAs, 65 long noncoding RNAs (lncRNAs), 59 microRNAs (miRNAs), and 229 circular RNAs (circRNAs) were differentially expressed (DE) in P12 compared with P4, with a similar trend in P6. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene set enrichment analysis (GSEA) identified several significant biological processes and pathways, including binding, ossification, and Wnt and PPAR signaling pathways. Interaction and co-expression/localization analyses were performed for DE mRNAs and lncRNAs, and several key lncRNAs, circRNAs, and important pathways like autophagy and mitophagy were identified in the competing endogenous RNA (ceRNA) network. Some key RNAs found in the bioinformatics analysis were validated. Our studies indicate that replicative senescence of MSCs is a continuous process, including widespread alterations in biological characteristics and global gene expression patterns that need to be considered before therapeutic applications of MSCs.

LncRNA and mRNA Expression Profiles in Methylprednisolone Stimulated Neural Stem Cells.

Spinal cord injury (SCI) is a devastating neurological disorder that affects thousands of individuals each year. Previously, our study in non-human primates with SCI demonstrated that methylprednisolone (MP) resulted in the dysfunction of neural stem cells (NSCs), which may help to explain the controversial roles of MP in SCI. However, the detailed mechanism is still unclear. In this manuscript, we investigated the LncRNA and mRNA expression profiles of NSCs treated with MP. A total of 63 differentially expressed LncRNAs and 174 differentially expressed mRNAs were identified. Gene ontology (GO) analysis showed that differentially expressed mRNAs were highly associated with terms related to regulation of external stimulation, secretion, and migration. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis results indicated that the PI3K-Akt signaling pathway contributed to the functions of MP treated NSCs. Besides, 3899 co-expression pairs were constructed among the differentially expressed LncRNA and mRNA, among which five predicted target mRNAs with the differentially expressed LncRNAs were identified. These results provide greater insight into the precise mechanisms of MP mediating NSC dysfunction in SCI.

ATF6 aggravates angiogenesis-osteogenesis coupling during ankylosing spondylitis by mediating FGF2 expression in chondrocytes.

Although angiogenesis-osteogenesis coupling is important in ankylosing spondylitis (AS), therapeutic agents targeting the vasculature remain elusive. Here, we identified activating transcription factor 6 (ATF6) as an important regulator of angiogenesis in the pathogenesis of AS. First, we found that ATF6 and fibroblast growth factor 2 (FGF2) levels were higher in SKG mice and in cartilage of pateints with AS1. The proangiogenic activity of human chondrocytes was enhanced by the activation of the ATF6-FGF2 axis following 7 days of stimulation with inflammatory factors, e.g., tumor necrosis factor alpha (TNF-α), interferon-γ (IFN-γ) or interleukin-17 (IL-17). Mechanistically, ATF6 interacted with the FGF2 promotor and promoted its transcription. Treatment with the ATF6 inhibitor Ceapin-A7 inhibited angiogenesis in vitro and angiogenesis-osteogenesis coupling in vivo. ATF6 may aggravate angiogenesis-osteogenesis coupling during AS by mediating FGF2 transcription in chondrocytes, implying that ATF6 represents a promising therapeutic target for AS.

The N6-methyladenosine demethylase ALKBH5 negatively regulates the osteogenic differentiation of mesenchymal stem cells through PRMT6.

N6-methyladenosine (m6A) modification is widespread in messenger RNAs and increasing evidence suggests the crucial roles of m6A in cell differentiation and tissue development. However, whether m6A modulates the osteogenic differentiation of mesenchymal stem cells (MSCs) has not been fully elucidated. Here we show that conditional knockout of the demethylase Alkbh5 in bone marrow MSCs strengthened bone mass in mice. Loss- and gain-of-function studies demonstrated that ALKBH5 negatively regulates the osteogenic differentiation of MSCs in vitro. At a mechanistic level, meRIP-seq and RNA-seq in MSCs following knockdown of ALKBH5 revealed changes in transcripts of PRMT6 containing consensus m6A motifs required for demethylation by ALKBH5. Furthermore, we found that ALKBH5 accelerates the degradation rate of PRMT6 mRNA in an m6A-dependent manner, and that the ALKBH5-PRMT6 axis regulates the osteogenesis of MSCs, mainly through activation of the PI3K/AKT pathway. Thus, our work reveals a different facet of the novel ALKBH5-PRMT6 axis that modulates the osteogenic differentiation of MSCs, which can serve as a target to improve the clinical use of MSCs.

KDM6B-mediated histone demethylation of LDHA promotes lung metastasis of osteosarcoma.

Rationale: Osteosarcoma (OS), the most common type of bone tumor, which seriously affects the patients' limb function and life quality. OS has a strong tendency of lung metastasis, and the five-year survival rate of patients with metastatic osteosarcoma is less than 20%. Thus, new treatment targets and strategies are urgently needed. Methods: The expression of the histone demethylase KDM6B and H3K27me3 levels in OS specimens were analyzed using quantitative PCR and immunohistochemical assays. The biological functions of KDM6B were determined using in vitro transwell, wound healing assays, and an in vivo orthotopic injection-induced lung metastasis model. Subsequently, chromatin immunoprecipitation sequencing (ChIP-seq) combined with transcriptomic RNA sequencing (RNA-seq), and subsequent ChIP-qPCR, western blot, and aerobic glycolysis assays were used to explore the mechanism of KDM6B function and validate the candidate target gene of KDM6B. Results: KDM6B expression was significantly upregulated in OS patients, and high KDM6B expression was associated with poorer prognosis in OS patients. Targeting KDM6B significantly inhibited OS cell migration in vitro and lung metastasis in vivo. RNA-seq and ChIP-seq analysis revealed that KDM6B increases lactate dehydrogenase LDHA expression in OS cells by directly mediating H3K27me3 demethylation. The phenotypes of inhibited cell metastasis in KDM6B-knockdown OS cells was reversed upon overexpression of LDHA. Finally, a small molecule inhibitor targeting KDM6B significantly inhibited OS cell migration in vitro and lung metastasis in vivo. Conclusions: Collectively, we elucidated that upregulated KDM6B facilitates tumor metastasis in OS via modulating LDHA expression. Our findings deepen the recognition of OS metastasis mechanism and suggest that KDM6B might be a new potential therapeutic target for the treatment of OS (especially highly metastatic OS).

SMAD-specific E3 ubiquitin ligase 2 promotes angiogenesis by facilitating PTX3 degradation in MSCs from patients with ankylosing spondylitis.

Dysregulated angiogenesis of mesenchymal stem cells (MSCs) is closely related to inflammation and disrupted bone metabolism in patients with various autoimmune diseases. However, the role of MSCs in the development of abnormal angiogenesis in patients with ankylosing spondylitis (AS) remains unclear. In this study, we cultured human umbilical vein endothelial cells (HUVECs) with bone marrow-derived MSCs from patients with AS (ASMSCs) or healthy donors (HDMSCs) in vitro. Then, the cocultured HUVECs were assayed using a cell counting kit-8 (CCK-8) to evaluate the cell proliferation. A wound healing assay was performed to investigate cell migration, and a tube formation assay was conducted to determine the angiogenesis efficiency. ASMSCs exhibited increased angiogenesis, and increased expression of SMAD-specific E3 ubiquitin ligase 2 (Smurf2) in MSCs was the main cause of abnormal angiogenesis in patients with AS. Downregulation of Smurf2 in ASMSCs blocked angiogenesis, whereas overexpression of Smurf2 in HDMSCs promoted angiogenesis. The pro-angiogenic effect of Smurf2 was confirmed by the results of a Matrigel plug assay in vivo. By functioning as an E3 ubiquitin ligase in MSCs, Smurf2 regulated the levels of pentraxin 3 (PTX3), which has been shown to suppress angiogenesis through the PTX3-fibroblast growth factor 2 pathway. Moreover, Smurf2 transcription was regulated by activating transcription factor 4-induced endoplasmic reticulum stress. In conclusion, these results identify novel roles of Smurf2 in negatively regulating PTX3 stability and promoting angiogenesis in ASMSCs.

Single-Cell Profiles of Age-Related Osteoarthritis Uncover Underlying Heterogeneity Associated With Disease Progression.

Objective: Osteoarthritis (OA) is the most common chronic degenerative joint disease, which represents the leading cause of age-related disability. Here, this study aimed to depict the intercellular heterogeneity of OA synovial tissues. Methods: Single-cell RNA sequencing (scRNA-seq) data were preprocessed and quality controlled by the Seurat package. Cell cluster was presented and cell types were annotated based on the mRNA expression of corresponding marker genes by the SingleR package. Cell-cell communication was assessed among different cell types. After integrating the GSE55235 and GSE55457 datasets, differentially expressed genes were identified between OA and normal synovial tissues. Then, differentially expressed marker genes were overlapped and their biological functions were analyzed. Results: Totally, five immune cell subpopulations were annotated in OA synovial tissues including macrophages, dendritic cells, T cells, monocytes and B cells. Pseudo-time analysis revealed the underlying evolution process in the inflammatory microenvironment of OA synovial tissue. There was close crosstalk between five cell types according to the ligand-receptor network. The genetic heterogeneity was investigated between OA and normal synovial tissues. Furthermore, functional annotation analysis showed the intercellular heterogeneity across immune cells in OA synovial tissues. Conclusion: This study offered insights into the heterogeneity of OA, which provided in-depth understanding of the transcriptomic diversities within synovial tissue. This transcriptional heterogeneity may improve our understanding on OA pathogenesis and provide potential molecular therapeutic targets for OA.

SNP-adjacent super enhancer network mediates enhanced osteogenic differentiation of MSCs in ankylosing spondylitis.

Ankylosing spondylitis (AS) is a rheumatic disease with pathological osteogenesis that causes bony ankylosis and even deformity over time. Mesenchymal stem cells (MSCs) are multipotent stem cells that are the main source of osteoblasts. We previously demonstrated that enhanced osteogenic differentiation of MSCs from AS patients (ASMSCs) is related to pathological osteogenesis in AS. However, the more concrete mechanism needs further exploration. Super enhancers (SEs) are dense clusters of stitched enhancers that control cell identity determination and disease development. Single-nucleotide polymorphisms (SNPs) regulate the formation and interaction of SEs and denote genes accounting for AS susceptibility. Via integrative analysis of multiomic data, including histone 3 lysine 27 acetylation (H3K27ac), chromatin immunoprecipitation sequencing (ChIP-seq), SNPs and RNA sequencing (RNA-seq) data, we discovered a transcription network mediated by AS SNP-adjacent SEs (SASEs) in ASMSCs and identified key genes, such as Toll-like receptor 4 (TLR4), interleukin 18 receptor 1 (IL18R1), insulin-like growth factor binding protein 4 (IGFBP4), transportin 1 (TNPO1) and proprotein convertase subtilisin/kexin type 5 (PCSK5), which are pivotal in osteogenesis and AS pathogenesis. The SASE-regulated network modulates the enhanced osteogenic differentiation of ASMSCs by synergistically activating the PI3K-Akt, NF-kappaB and Hippo signaling pathways. Our results emphasize the crucial role of the SASE-regulated network in pathological osteogenesis in AS, and the preferential inhibition of ASMSC osteogenic differentiation by JQ1 indicates that SEs may be attractive targets in future treatment for new bone formation in AS.

Aberrantly Expressed lncRNAs and mRNAs of Osteogenically Differentiated Mesenchymal Stem Cells in Ossification of the Posterior Longitudinal Ligament.

Ectopic bone formation is the chief characteristic of ossification of the posterior longitudinal ligament (OPLL). Emerging evidence has revealed that long non-coding RNAs (lncRNAs) can regulate the osteogenic differentiation of mesenchymal stem cells (MSCs), which are the main cells responsible for bone formation. However, the role of lncRNAs in the pathogenesis of OPLL remains unclear. In this study, 725 aberrantly expressed lncRNAs and 664 mRNAs in osteogenically differentiated MSCs from OPLL patients (OPLL MSCs) were identified by microarrays and confirmed by qRT-PCR assays. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the most enriched pathways included the p53, JAK-STAT, and PI3K-Akt signaling pathways. The co-expression network showed the interactions between the aberrantly expressed lncRNAs and mRNAs in OPLL MSCs, and the potential targets and transcription factors of the lncRNAs were predicted. Our research demonstrated the aberrantly expressed lncRNA and mRNA and the potential regulatory networks involved in the ectopic bone formation of OPLL. These findings imply that lncRNAs may play a vital role in OPLL, which provides a new perspective on the pathogenesis of OPLL.

Influence of tea polyphenol and bovine serum albumin on tea cream formation by multiple spectroscopy methods and molecular docking.

The sensory qualities and shelf life of tea beverage strongly affected by tea cream that forms by the interaction of polyphenols and protein. The study aimed to investigate the effects of the interactions between tea polyphenols (TPs) and bovine serum albumin (BSA) on tea cream formation at different concentrations. The tea cream formation increased with TPs and BSA concentration increased. The optimal concentration (TPs: 800 mg/L, BSA: 40 mg/L), for high clarities and contents of phytochemicals, was selected by the technique for order preference by similarity to ideal solution (C = 0.7572). The interaction mechanism of TPs-BSA was investigated by fluorescence spectroscopy, UV-visible absorption spectroscopy, synchronous fluorescence spectroscopy, and molecular docking. TPs interacted with BSA via static quenching process, affecting tryptophan and tyrosine residue microenvironment of BSA. Ester catechins had more binding affinity than non-ester catechins. Hydrogen bonds were the main interaction forces of TPs-BSA.