Serum from patients with ankylosing spondylitis can increase PPARD, fra-1, MMP7, OPG and RANKL expression in MG63 cells

Anaerobic metabolism promotes breast cancer survival via Histone-3 Lysine-18 lactylation mediating PPARD axis

Histone lactylation plays a crucial role in cancer progression, but its impact on breast cancer (BC) tumorigenesis is still unclear. We utilized chromatin immunoprecipitation sequencing with H3K18la antibodies, transcriptomics of clinical BC samples, and proteomics and ATAC-seq analyses of in vivo tumors to identify the genes regulated by H3K18la and the transcription factor PPARD. qPCR and Western blot assays were used to detect expressions of molecules. We discovered that H3K18la levels were higher in BC tissues compared to adjacent non-cancerous tissues. H3K18la promoted the expression of PPARD, which in turn influenced the transcription of AKT, but not ILK. ATAC-seq analysis revealed that glycolysis in BC cells enhanced chromatin accessibility. Additionally, we confirmed that HDAC2 and HDAC3 act as "erasers" for H3 lysine lactylation. During the proteomics analysis, AKT-phosphorylation in the aerobic respiration inhibitor group exhibited an apparent disparity and activity. Our study demonstrated that changes in H3K18la in BC and its downstream transcription factor PPARD support cell survival under anaerobic glycolysis conditions. PPARD accelerated cancer proliferation by promoting the transcription and phosphorylation of AKT. This highlights the therapeutic potential of targeting the H3K18la/PPARD/AKT axis in breast cancer, providing new insights into epigenetic regulation and cancer metabolism (Trial registration: The study was approved by the Research Ethics Committee Shandong Provincial Third Hospital (KYLL-2023057; https://www.medicalresearch.org.cn/ )).

Aberrant lncRNA–mRNA expression profile and function networks during the adipogenesis of mesenchymal stem cells from patients with ankylosing spondylitis

Objective: We have already demonstrated that mesenchymal stem cells from patients with ankylosing spondylitis (ASMSCs) exhibited greater adipogenic differentiation potential than those from healthy donors (HDMSCs). Here, we further investigated the expression profile of long noncoding RNA (lncRNA) and mRNA, aiming to explore the underlying mechanism of abnormal adipogenic differentiation in ASMSCs.

Methods: HDMSCs and ASMSCs were separately isolated and induced with adipogenic differentiation medium for 10 days. Thereafter, lncRNAs and mRNAs that were differentially expressed (DE) between HDMSCs and ASMSCs were identified via high-throughput sequencing and confirmed by quantitative real-time PCR (qRT–PCR) assays. Then, the DE genes were annotated and enriched by GO analysis. In addition, protein interaction network was constructed to evaluate the interactions between DE mRNAs and to find hub nodes and study cliques. Besides, co-expression network analysis was carried out to assess the co-expressions between DE mRNA and DE lncRNAs, and competing endogenous RNA (ceRNA) network analysis were conducted to predict the relationships among lncRNAs, mRNAs and miRNAs. The signaling pathways based on the DE genes and the predicted DE genes were enriched by KEGG analysis.

Results: A total of 263 DE lncRNAs and 1376 DE mRNAs were found during adipogenesis in ASMSCs. qRT–PCR indicated that the expression of the top 20 mRNAs and the top 10 lncRNAs was consistent with the high-throughput sequencing data. Several lncRNAs (NR_125386.1, NR_046473.1 and NR_038937.1) and their target genes (SPN and OR1AIP2), together with the significantly co-expressed pairs of DE lncRNAs and DE mRNAs (SLC38A5-ENST00000429588.1, TMEM61-ENST00000400755.3 and C5orf46-ENST00000512300.1), were closely related to the enhanced adipogenesis of ASMSCs by modulating the PPAR signaling pathway.

Conclusion: Our study analyzed the expression profiles of DE lncRNAs and DE mRNAs during adipogenesis in ASMSCs and HDMSCs. Several DE lncRNAs, DE mRNAs and signaling pathways that probably participate in the aberrant adipogenesis of ASMSCs were selected for future study. These results will likely provide potential targets for our intervention on fat metaplasia and subsequent new bone formation in patients with AS in the future.

Serum RANKL levels in Chinese patients with ankylosing spondylitis: a meta-analysis

Objective

We aimed to determine the association between serum receptor activator of nuclear factor-kappa B ligand (sRANKL) levels and ankylosing spondylitis (AS) in Chinese patients.

Methods

The PubMed, Cochrane Library, Embase, Chinese Biomedical Database, Web of Science, China National Knowledge Infrastructure, VIP, and Wan Fang databases were searched for studies conducted before October 1, 2020, without language restrictions. STATA version 12.0 and Revman version 5.3 were used to analyze the data. The standard mean differences (SMDs) and corresponding 95% confidence intervals (95% CIs) were calculated.

Results

Twelve clinical case–control studies, including 585 patients with AS and 423 healthy controls, were included. The combined SMD for sRANKL suggested that the sRANKL level was significantly higher in Chinese patients with AS than in healthy controls (SMD: 3.27, 95% CI 2.11–4.43, P < 0.00001). Serum RANKL-related factor osteoprotegerin (OPG) levels (SMD: 0.86, 95% CI 0.09–1.64, P < 0.03) were lower in the Chinese patients with AS than in healthy controls, and the RANKL/OPG ratio (SMD = 1.05, 95% CI 0.64–1.46, P < 0.00001) in Chinese patients with AS was approximately the same as that of healthy controls. Subgroup analysis indicated that patients from North and South China had higher sRANKL levels than controls; the sRANKL levels of patients from South China were higher in the subgroup with a Bath Ankylosing Spondylitis Functional Index (BASFI) of > 4 than those of patients in other subgroups. In terms of duration, patients with AS for > 8 years had higher sRANKL levels than health controls. Other subgroup analyses were conducted by region, language, source of control, age, and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). In these subgroups, the sRANKL levels were significantly higher in the patients with AS than in healthy controls. The BASFI and BASDAI were sources of heterogeneity.

Conclusions

The sRANKL levels are higher in Chinese patients with AS, especially among those from South China. sRANKL levels may be positively correlated with the pathogenesis of AS among Chinese patients.

MicroRNA let-7i-3p affects osteoblast differentiation in ankylosing spondylitis via targeting PDK1

Ankylosing spondylitis (AS) is a chronic autoimmune disease in which let-7i has been studied to involved. But, whether let-7i-3p could regulate osteoblast differentiation in AS remains unclear. This research targeted to decipher the impact of let-7i-3p on AS progression by modulating pyruvate dehydrogenase kinase 1 (PDK1). The bone mineral density of femur and lumbar vertebra and the maximum loading and bending elastic modulus of tibia, tumor necrosis factor-α (TNF-α), matrix metalloproteinase (MMP)-3, osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) in serum of AS mice, the pathological condition of synovial tissue were determined via let-7i-3p inhibitor and OE-PDK1 in animal experiment. Also, the cell viability and ALP activity were measured by let-7i-3p inhibitor and OE-PDK1 in cell experiments. let-7i-3p and PDK1 expression were detected. Let-7i-3p raised and PDK1 declined in AS mice. Depleted let-7i-3p and restored PDK1 increased bone mineral density and maximum loading and bending elastic modulus of tibia, reduced TNF-α, MMP-3 and RANKL contents, attenuated the pathological condition of synovial tissue and raised OPG content in AS mice. In cell experiments, up-regulating PDK1 and down-regulating let-7i-3p enhanced cell viability and ALP activity in AS mice. Low expression of let-7i-3p could enhance osteoblast differentiation in AS by up-regulating PDK1.Abbreviations: AS: Ankylosing spondylitis; PDK1: pyruvate dehydrogenase kinase 1; TNF-α: tumor necrosis factor-α MMP: matrix metalloproteinase; OPG: osteoprotegerin; RANKL: receptor activator of nuclear factor-κB ligand; miRNAs: MicroRNAs; BMD: bone mineral density; PFA: paraformaldehyde; NC: negative control; OE: overexpression; HE: Hematoxylin-eosin; PBS: phosphate-buffered saline; EDTA: ethylene diamine tetraacetic acid; DMEM: Dulbecco's Modified Eagle Medium; RT-qPCR: Reverse transcription quantitative polymerase chain reaction; GAPDH: glyceraldehyde phosphate dehydrogenase; UTR: untranslated region; WT: wild type; MUT: mutant type.

Cancer-associated fibroblast-derived SDF-1 induces epithelial-mesenchymal transition of lung adenocarcinoma via CXCR4/β-catenin/PPARδ signalling

Cancer-associated fibroblasts (CAFs) contribute to tumour epithelial-mesenchymal transition (EMT) via interaction with cancer cells. However, the molecular mechanisms underlying tumour-promoting EMT of CAFs in lung adenocarcinoma (ADC) remain unclear. Here, we observed that CAFs isolated from lung ADC promoted EMT via production of stromal cell-derived factor-1 (SDF-1) in conditioned medium (CM). CAF-derived SDF-1 enhanced invasiveness and EMT by upregulating CXCR4, β-catenin, and PPARδ, while downregulating these proteins reversed the effect. Furthermore, RNAi-mediated CXCR4 knockdown suppressed β-catenin and PPARδ expression, while β-catenin inhibition effectively downregulated PPARδ without affecting CXCR4; however, treatment with a PPARδ inhibitor did not inhibit CXCR4 or β-catenin expression. Additionally, pairwise analysis revealed that high expression of CXCR4, β-catenin, and PPARδ correlated positively with 75 human lung adenocarcinoma tissues, which was predictive of poor prognosis. Thus, targeting the CAF-derived, SDF-1-mediated CXCR4 β-catenin/ PPARδ cascade may serve as an effective targeted approach for lung cancer treatment.

Bone Protective Effect of Extra-Virgin Olive Oil Phenolic Compounds by Modulating Osteoblast Gene Expression

The phenolic compounds of extra-virgin olive oil can act at various levels to protect individuals against cardiovascular and neurodegenerative diseases, cancer, and osteoporosis, among others. Polyphenols in extra-virgin olive oil can stimulate the proliferation of osteoblasts, modify their antigen profile, and promote alkaline phosphatase synthesis. The objective of this work was to determine the effect of different extra-virgin olive oil phenolic compounds on the gene expression of osteoblast-related markers. The cells of the MG63 osteoblast line were cultured for 24 h with 10⁻⁶ M of the phenolic compounds ferulic acid, caffeic acid, coumaric acid, apigenin, or luteolin. The expression of studied markers was quantified using quantitative real-time polymerase chain reaction (q-RT-PCR). The expression by MG63 osteoblasts of growth and differentiation/maturation markers was modified after 24 h of treatment with 10⁻⁶ M of the phenolic compounds under study, most of which increased the gene expression of the transforming growth factor β1 (TGF-β1), TGF-β receptor 1,2 and 3 (TGF-βR1, TGF-βR2, TGF-βR3), bone morphogenetic protein 2 and 7 (BMP2, BMP7), run-related transcription factor 2 (RUNX-2), Alkaline phosphatase (ALP), Osteocalcin (OSC), Osterix (OSX), Collagen type I (Col-I) and osteoprotegerin (OPN). The extra-virgin olive oil phenolic compounds may have a beneficial effect on bone by modulating osteoblast physiology, which would support their protective effect against bone pathologies.

I-BET151 inhibits expression of RANKL, OPG, MMP3 and MMP9 in ankylosing spondylitis in vivo and in vitro

Ankylosing spondylitis (AS) is characterized by osteoclastogenesis and inflammatory bone resorption. The present study aimed to investigate the effect of bromodomain and extra-terminal domain (BET) protein inhibitor I-BET151 on AS process. A total of 38 AS Chinese patients were recruited and a further 38 sex- and age-matched healthy participants were selected as control. The Bath AS Function Index and Bath AS Disease Activity Index were assessed in AS patients and levels of erythrocyte sedimentation rate and C-reactive protein were measured in AS and healthy groups. Serum from AS patients was used to induce MG63 osteoblasts and BET inhibitor I-BET151 at concentrations of 50, 100 and 200 ng/ml used for treatment of the cells. A HLA-B27/β2m transgenic AS Lewis rat model was established and treated with 30 mg/kg I-BET151 for 5 weeks. Levels of receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), matrix metalloproteinase (MMP)3, and MMP9 were measured using ELISA in vivo and additionally detected with western blotting and polymerase chain reaction in vitro. The levels of RANKL, OPG, MMP3 and MMP9 were upregulated in AS serum, AS serum treated MG63 cells and HLA-B27/β2m transgenic AS rats. Conversely, levels of RANKL, OPG, MMP3 and MMP9 were significantly inhibited in cells or animals treated with I-BET151. Overall, the results of the present study demonstrated that BET inhibitor I-BET151 suppresses levels of RANKL, OPG, MMP3 and MMP9 in AS in vivo and in vitro. I-BET151 may exhibit the potential to be used as a therapeutic in the treatment of AS patients.

Single nucleotide polymorphisms of ABCB1 gene and response to etanercept treatment in patients with ankylosing spondylitis in a Chinese Han population

BACKGROUND

Etanercept was highly recommended for patients with ankylosing spondylitis (AS), as its efficacy has been confirmed in AS, while genetic polymorphisms, by affecting drug metabolism or drug receptor, lead to interindividual variability in drug disposition and efficacy. Therefore, this study aims to investigate whether ABCB1 gene polymorphisms can predict therapeutic response to etanercept in patients with AS.

METHODS

A total of 185 patients with AS in our hospital were recruited into our study from December 2012 to May 2015. The frequency distributions of genotype and allele of rs2032582, rs1128503, and rs1045642 were detected by polymerase chain reaction (PCR) and electrophoresis verification enzyme products method. AS patients received etanercept treatment for 12 weeks, followed by this would be evaluated by the bath AS disease activity index (BASDAI) score improvement and the assessment of spondyloArthritis international society 20/50/70 (ASAS20/50/70) score improvements to explore the relationship between genotype of ABCB1 gene polymorphisms and therapeutic response to etanercept in patients with AS.

RESULTS

After 12 weeks, the BASDAI score mean improvement value of rs2032582 A/A genotype was 2.87 ± 0.52. The ratios of patients with rs2032582 A/A genotype reaching the BASDAI50 and ASAS20 evaluation criteria were 64.29% and 92.86%, respectively. The results indicated that efficacy of etanercept was promoted in rs2032582 A/A genotype. The BASDAI score mean improvement value of rs1128503 C/C genotype was 2.79 ± 0.54 after 12 weeks. The ratios of patients with rs1128503 C/C genotype reaching the BASDAI50 and ASAS20 evaluation criteria were 66.67% and 93.94%, respectively. The results indicated that efficacy of etanercept was promoted in rs1128503 C/C genotype. However, no significant associations were observed between rs1045642 and therapeutic response to etanercept in AS patients.

CONCLUSION

ABCB1 gene rs2032582 and rs1128503 polymorphisms may be associated with the efficacy of etanercept in AS patients. ABCB1 gene polymorphisms can act as biological indicators of etanercept efficacy.