Application of exosome-derived noncoding RNAs in bone regeneration: Opportunities and challenges.

With advances in the fields of regenerative medicine, cell-free therapy has received increased attention. Exosomes have a variety of endogenous properties that provide stability for molecular transport across biological barriers to cells, as a form of cell-to-cell communication that regulates function and phenotype. In addition, exosomes are an important component of paracrine signaling in stem-cell-based therapy and can be used as a stand-alone therapy or as a drug delivery system. The remarkable potential of exosomes has paved the pathway for cell-free treatment in bone regeneration. Exosomes are enriched in distinct noncoding RNAs (ncRNAs), including microRNAs, long ncRNAs and circular RNAs. Different ncRNAs have multiple functions. Altered expression of ncRNA in exosomes is associated with the regenerative potential and development of various diseases, such as femoral head osteonecrosis, myocardial infarction, and cancer. Although there is increasing evidence that exosome-derived ncRNAs (exo-ncRNAs) have the potential for bone regeneration, the detailed mechanisms are not fully understood. Here, we review the biogenesis of exo-ncRNA and the effects of ncRNAs on angiogenesis and osteoblast- and osteoclast-related pathways in different diseases. However, there are still many unsolved problems and challenges in the clinical application of ncRNA; for instance, production, storage, targeted delivery and therapeutic potency assessment. Advancements in exo-ncRNA methods and design will promote the development of therapeutics, revolutionizing the present landscape.

Identification of long non­coding RNAs expressed during the osteogenic differentiation of human bone marrow­derived mesenchymal stem cells obtained from patients with ONFH.

Long non­coding RNAs (lncRNAs) are crucial for the occurrence and development of numerous diseases. Although lncRNAs are involved in the biological activities of stem cells and play crucial roles in stem cell differentiation, the expression of specific lncRNAs during human bone marrow­derived mesenchymal stem cell (hBMSC) osteogenic differentiation in osteonecrosis of the femoral head (ONFH) and their regulatory roles have not yet been fully elucidated. To the best of our knowledge, the present study is the first to characterize lncRNA expression profiles during hBMSC osteogenic differentiation in ONFH using microarray analysis and RT­qPCR to confirm the microarray data. A total of 24 downregulated and 24 upregulated lncRNAs were identified and the results of RT­qPCR were found to be consistent with those of microarray analysis. Bioinformatics analyses, using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, were conducted to explore the possible mechanisms and identify the signaling pathways that the lncRNAs are involved in. GO analysis revealed significant changes in the intracellular organelle, Ras protein signal transduction and transferase activity. KEGG pathway analysis revealed that the lncRNAs were closely associated with fatty acid metabolism, apoptosis and the TGF­ß signaling pathway. The overexpression of MAPT antisense RNA 1 (MAPT­AS1) was found to promote osteogenesis and inhibit the adipogenesis of hBMSCs at the cellular and mRNA levels. On the whole, the findings of the present study identified the lncRNAs and their roles in hBMSCs undergoing osteogenic differentiation in ONFH and provide a new perspective for the pathogenesis of ONFH.

LINC00473 regulated apoptosis, proliferation and migration but could not reverse cell cycle arrest of human bone marrow mesenchymal stem cells induced by a high-dosage of dexamethasone.

Dysfunction of bone marrow mesenchymal stem cells (BMSCs) is involved in the pathogenesis of steroid-induced osteonecrosis of the femoral head (SONFH). Long noncoding RNAs (lncRNAs) contribute to biological effects exerted on BMSCs by regulating the expression of genes. However, most recent studies have focused on the role of lncRNAs in modulating the imbalance between osteogenic and adipogenic differentiation but not apoptosis, proliferation, cell cycle and migration of BMSCs, especially in Dex-treated BMSCs. In this study, we conducted a microarray analysis to investigate the differential expression profiles of lncRNAs between human BMSCs (hBMSCs) obtained from patients with SONFH and control patients with femoral neck fracture. The microarray analysis showed that a total of 48 differentially expressed lncRNAs were identified in hBMSCs between the two groups, including 24 upregulated lncRNAs and 24 downregulated lncRNAs. Among of them, LINC00473 was found to be significantly downregulated. In the following study, we found that 10-6 mol/L Dex significantly inhibited proliferation, arrested cell cycle at the G1 phase, increased caspase-3 activity, induced apoptosis and impeded the migration of hBMSCs, while downregulation of the expression of LINC00473 produced results that were in line with the results of the microarray analysis in a time-dependent manner. Interestingly, upregulation of LINC00473 attenuated the negative effects caused by 10-6 mol/L Dex on hBMSCs, except for cell cycle arrest. Furthermore, it should be noted that LINC00473 had no effect on the proliferation and cell cycle of hBMSCs in the absence of Dex. Collectively, our data revealed that LINC00473 attenuated apoptosis, promoted the proliferation and migration of Dex-induced hBMSCs, which are not involved in interference with the cell cycle of hBMSCs.

Angiotensin II inhibits osteogenic differentiation of isolated synoviocytes by increasing DKK-1 expression.

The renin-angiotensin system contributes to the pathogenesis of rheumatoid arthritis, but that the mechanism is unclear. This study aims to investigate the effect of angiotensin II (Ang II) on osteogenic differentiation of synoviocytes and the underlying mechanism. Ang II was showed to inhibite osteogenic differentiation of synoviocytes, which was mitigated by a Dickkopf-1 (DKK-1) inhibitor. DKK-1 was upregulated by Ang II, which was weakened by the Ang II type 1 receptor (AT1R) blocker, reactive oxygen species (ROS) scavenger, and p38 inhibitor. Ang II increased the levels of AT1R, ROS, and NADPH oxidase (NOX), and the upregulations were mitigated by the AT1R blocker or NOX inhibitor. Furthermore, Ang II activated the p38 pathway, which was blocked by the AT1R blocker, ROS scavenger, or siRNA-MKK3. In brief, these results indicate that Ang II upregulates NOX expression and ROS production via AT1R, activates the MKK3/p38 signaling, and in turn upregulates DKK-1 expression, participating in the inhibition of osteogenic differentiation of synoviocytes.

Knockdown of enhancer of rudimentary homolog inhibits proliferation and metastasis in ovarian cancer by regulating epithelial-mesenchymal transition.

Ovarian cancer (OC) is the deadliest gynecological malignancy. The pathogenesis of molecular in epithelial ovarian cancer (EOC), main histological type of OC, has not been completely defined. Enhancer of rudimentary homolog (ERH) had been reported to participate in transcriptional regulation, mRNA splicing, DNA repair and DNA synthesis by binding a variety of proteins. In this study, immunohistochemical staining revealed that the protein expression of ERH was associated with histological type, lymph node metastasis and pathological grade in EOC patients. To verify the association of ERH with the prognosis of OC, a GSE microarray dataset was downloaded from the Gene Expression Omnibus (GEO) database. Survival analysis suggested that ERH may be associated with poor prognosis of OC. In addition, shRNA was used to knockdown the protein and mRNA expression levels of ERH in the OC cell line SKOV3. Inhibition of ERH expression slowed proliferation, promoted apoptosis and inhibited metastasis and invasion by regulating epithelial-mesenchymal transition (EMT) in SKOV3 cells. These results indicate that ERH protein promotes the development of OC and provides an experimental basis for ERH as the potential target for ovarian cancer treatment.

Hip survival rate in the patients with avascular necrosis of femoral head after transtrochanteric rotational osteotomy: a systematic review and meta-analysis.

BACKGROUND: The clinical outcome of transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head (ONFH) remains controversial, and the promising clinical results of several Japanese studies could not be reproduced in American and European studies. Trying to solve controversies on TRO for ONFH rising from apparently conflicting studies, a meta-analysis was conducted to assess the 5- and 10-year hip survival rates (with conversion to artificial joint replacement and radiographic failure as endpoints) after TRO. METHODS: All eligible studies were searched in seven comprehensive databases including PubMed, Web of Science, Embase, Cochrane Library, VIP Database, China Knowledge Resource Integrated Database, and Wan Fang Database prior to June 2019. The outcomes evaluated were 5- and 10-year hip survival rates after TRO. The odds ratio and risk difference for the non-comparative binary data with the 95% confidence intervals (CIs) were calculated for each outcome. The included studies were assessed for methodologic bias and potential reasons for heterogeneity were explored. RESULTS: Nineteen studies of TRO for ONFH were eligible for this meta-analysis according to inclusion criteria. Based on the previous report, two calculation methods (Methods 1 and 2) were adopted in this meta-analysis. Furthermore, we performed a sub-group analysis of the 5- and 10-year hip survival rates (Method 1) after TRO for ONFH: Asian sub-population and non-Asian sub-population. Taking conversion to artificial joint replacement as the endpoint, 5- and 10-year hip survival rates (Method 1) after TRO for ONFH in the Asian population were 0.86 (95% CI = 0.82-0.89) and 0.72 (95% CI = 0.65-0.78), respectively, and 5- and 10-year hip survival rates after TRO for ONFH in the non-Asian population were 0.55 (95% CI = 0.43-0.67) and 0.42 (95% CI = 0.28-0.55), respectively. The 5- and 10-year hip survival rates (Method 2) after TRO for ONFH were 0.90 (95% CI = 0.79-0.95) and 0.89 (95% CI = 0.81-0.94), respectively. Taking radiographic failure as the endpoint, 5- and 10-year hip survival rates after TRO for ONFH were 0.70 (95% CI = 0.64-0.76) and 0.53 (95% CI = 0.46-0.61), respectively. CONCLUSIONS: The 5- and 10-year hip survival rates after TRO for ONFH were satisfactory in the Asian population, and were acceptable in the non-Asian population despite high early failure rates.

Association Between the Angiotensin-Converting Enzyme Gene Insertion/Deletion Polymorphism and Avascular Necrosis of the Femoral Head.

Objective: This study investigated the association between the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and avascular necrosis of the femoral head (ANFH). Materials and Methods: The ACE gene I/D polymorphism was determined in 279 nontraumatic, ANFH Han Chinese patients (divided into idiopathic and steroid- and alcohol-induced subgroups) and 276 age- and gender-matched healthy controls using the polymerase chain reaction. Results: The frequencies of the ACE DD genotype and D allele were significantly higher among the ANFH patients as a whole and also in the idiopathic and steroid- and alcohol-induced ANFH subgroups compared to healthy controls (p < 0.05 for all). Additionally, the DD genotype, compared with the ID+II, ID, and II genotypes, conferred a higher risk of developing ANFH across all clinical subgroups (p < 0.001, odds ratio [OR] = 2.508; p < 0.001, OR = 2.072; p < 0.001, OR = 3.684, respectively) as well in each of the subgroups examined individually, including the idiopathic subgroup (p < 0.001, OR = 2.579; p < 0.001, OR = 2.091; p < 0.001, OR = 3.994, respectively), the steroid-induced subgroup (p = 0.005, OR = 2.345; p = 0.031, OR = 2.050; p = 0.007, OR = 3.000, respectively), and the alcohol-induced subgroup (p < 0.001, OR = 2.488; p = 0.012, OR = 2.050; p = 0.011, OR = 2.659, respectively) of ANFH patients. The ID genotype, compared with the II genotype, conferred a higher risk across all subtypes analyzed together, and in the idiopathic subgroup (p = 0.013, OR = 1.778; p = 0.028, OR = 1.910) analyzed separately. Additionally, the D allele, in comparison with the I allele, conferred a relatively higher risk across all subgroups (p < 0.001, OR = 2.101) as well as in each of the three subgroups examined individually (idiopathic: p < 0.001, OR = 2.178; steroid-induced: p = 0.003, OR = 1.910; and alcohol-induced: p < 0.001, OR = 2.094). Conclusion: The ACE DD and ID genotypes and D allele may be risk factors for susceptibility to ANFH in the Chinese population.

Role of Brd4 in the production of inflammatory cytokines in mouse macrophages treated with titanium particles.

Brd4 protein is an important epigenetic regulator involved in the process of inflammatory cytokine production in many diseases. However, whether and how Brd4 participates in the process of wear-particle-induced inflammation remain unclear. This study aimed to investigate the potential role of Brd4 in titanium (Ti) particle-induced inflammatory cytokine production in mouse macrophage RAW264.7 cells. Our experiment detected Brd4 expressed in both normal synovium and periprosthetic osteolysis interface membrane, but the expression increased in the interface membrane as compared with that in normal synovium. Treatment with Ti particles significantly increased TNF-α, IL-6, and IL-1ß production in RAW264.7 cells, which was inhibited by JQ1 or Brd4-siRNA. Ti particles enhanced the expression of Brd4, which was abrogated by JQ1. Ti particles enhanced NF-κB p65 and IKK phosphorylation and attenuated IκBα protein expression, which were abrogated by JQ1. Co-immunoprecipitation analysis indicated that Ti particles promoted the binding of Brd4 to acetylated NF-κB p65 (lysine-310), which was also abrogated in JQ1-treated RAW264.7 cells. In conclusion, Brd4 expression increases in interface membrane and Brd4 participates in the production of pro-inflammatory cytokines induced by Ti particles via promoting the activation of NF-κB signaling and binding to acetylated NF-κB p65 (lysine-310) in mouse macrophages.

The reciprocal influences of prognosis between two types of surgical interventions and early breast cancer patients with diverse luminal subtypes: A meta-analysis.

BACKGROUND: To investigate and compare the effects of breast-conserving therapy (BCT) and mastectomy on the disease recurrence and long-term survival in early-stage luminal breast cancer and the difference in prognosis across diverse luminal subtypes receiving single surgical modality. METHODS: The databases of PubMed and Embase were retrieved to select eligible trials that were published from inception to 13 November 2018. The clinical trials that offered the details about recurrent disease and/or survival in luminal tumors underwent BCT or mastectomy met the inclusion criteria (n=24). With the random- or fixed-effect model basing on heterogeneity Chi test with its significant level of P < .1, pooled odds ratio (OR) with its 95% CI, and P value were identified for endpoints. RESULTS: The analyzed data were constituted of 25 qualified trials with 13,032 unique women suffered from luminal cancers. The fixed-effect models were utilized. On the LRR regarding BCT versus mastectomy, the pooled data indicated no significant difference in luminal carcinomas (OR, 0.84; 95%CI, 0.43-1.64; P = .61; n = 867). In BCT cohort, the pooled data showed that there were some significant benefits favoring luminal A over luminal B in LR (OR, 0.61; 95%CI, 0.46-0.81; P = .0007; n = 5406), DM (OR, 0.53; 95%CI, 0.41-0.69; P < .00001; n = 4662), DFS (OR, 0.59; 95%CI, 0.36-0.96; P = .03; n = 776) and OS (OR, 0.65; 95%CI, 0.42-0.99; P = .05; n = 1149), but not in LRR (OR, 0.74; 95%CI, 0.48-1.13; P = .16; n = 3732), coupled with luminal A/B over luminal-HER2 in LRR (OR, 0.43; 95%CI, 0.25-0.76; P = .004; n = 890), DM (OR, 0.56; 95%CI, 0.35-0.90; P = .02; n = 1396), DFS (OR, 0.47; 95%CI, 0.27-0.83; P = .009; n = 532); in mastectomy cohort, there were apparent advantages of LRR (OR, 0.58; 95%CI, 0.36-0.92; P = .02; n = 1768), LR (OR,0.56; 95%CI, 0.38-0.83; P = .004; n = 1209), DM (OR, 0.58; 95%CI, 0.40-0.84; P = .004; n = 652) and OS (OR, 0.62; 95%CI, 0.43-0.89; P = .009; n = 652) in luminal A vs luminal B. CONCLUSION: For early luminal breast cancer, the equality of LRR was achieved in BCT and mastectomy. In comparison, luminal A cancers benefit the most improved tumor re-appearence and survival in luminal diseases regardless of the option of surgical modality, whereas luminal-HER2 is affected by the worst clinical outcomes in them who follows BCT.

[Correlation of human papillomavirus (HPV) and HPV vaccines with male reproductive health].

HPV is a very common virus worldwide spread by direct contact and involved in male reproductive health-related diseases such as infertility, condyloma acuminatum, and penile cancer. The development of HPV vaccines has contributed to the effective prevention of various subtypes of HPV and protection of males from HPV infection, especially the partners of HPV-positive females, the men who have sex with men, and those with a psychological fear of HPV infection. Therefore, HPV vaccines play an important role in the protection of males.

The renin-angiotensin system in the synovium promotes periarticular osteopenia in a rat model of collagen-induced arthritis.

Periarticular osteopenia is the most specific hallmark of rheumatoid arthritis (RA). The renin-angiotensin system (RAS) in the synovium has been found to participate in the pathogenic process of RA. This study examined whether and how RAS regulates periarticular osteopenia in RA. The synovial tissues from patients with RA and osteoarthritis (OA) were prepared. Female Sprague-Dawley rats were treated with either saline, bovine type II collagen (CII) to induce arthritis (CIA), or CII combined with perindopril, an inhibitor of angiotensin-converting enzyme (ACE). Expressions of RAS components, including AT1R, AT2R and ACE, in human and rat synovial tissues were detected. Bone mass of rat joints was examined. Levels of RANKL, OPG and DKK-1 in rat synovium and expressions of TRAF6 and ß-catenin in rat bone were examined. The results showed that AT1R, AT2R and ACE in human and rat synovium were up-regulated, but the increased ACE in rat synovial tissues was abrogated by perindopril. While CIA rats displayed increased bone resorption and decreased bone formation, perindopril treatment almost completely abrogated the RAS-mediated osteopenia, indicating that inhibition of ACE reduced the joint damages in rats. The expressions of RANKL and DKK-1 increased in CIA rats as compared with those in the control; TRAF6 was up-regulated and ß-catenin was down-regulated in the bone tissues of CIA rats. The changes were then reversed by the use of perindopril. Our findings demonstrate that RAS in the synovium promotes periarticular osteopenia by increasing bone resorption and decreasing bone formation through modulating the RANKL/RANK/TRAF6 and Wnt/ß-catenin pathways.