Identification of functional lncRNAs based on competing endogenous RNA network in osteoblast differentiation.

Adult human mesenchymal stem cells have the potential to differentiate into osteoblast, which plays crucial roles in bone regeneration and repair. Some transcriptional factors (TFs), such as BMP-2 and RUNX2, have been demonstrated to control the differentiation processes. It is important to discover more key regulators in osteoblast differentiation. Recently, some studies found long noncoding RNAs (lncRNAs) participating in osteoblast differentiation, such as MALAT1, DANCR, and ANCR. In this study, we performed a network-based computational analysis to investigate the lncRNA-messenger RNA (mRNA) crosstalks via integrating microRNA (miRNA)-RNA interactions, gene coexpression, and protein-protein interactions. First, multiple topology analyses were performed to osteoblast-differentiation-related lncRNA-mRNA network (ODLMN). Several lncRNAs with central topology structures were identified as key regulators. Results showed that these lncRNAs participated in osteoblast differentiation via phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase, and Ras signals. Previous studies have demonstrated that lncRNAs exert functions by involving in close modules. Second, after performing module searching in ODLMN, two functional modules were identified, which played crucial roles through involving in PI3K/protein kinase B, cyclic adenosine 3',5'-monophosphate, and hypoxia-inducible factor 1 pathways. Third, a subset of core lncRNA-TF crosstalks that might form feedback loops to control the biological processes in osteoblast differentiation was identified. These core lncRNA-TF feedback loops showed more TF binding affinity than other lncRNAs. All these results can help us to uncover the molecular mechanism and provide new targets for bone regeneration and repair.

Laquinimod Mitigated IL-1ß-Induced Impairment of the Cartilage Extracellular Matrix in Human ATDC5 Chondrocytes.

To date, a safe and reliable treatment of osteoarthritis (OA) has not yet been announced. Inflammatory response and degradation of the articular extracellular matrix (ECM) induced by IL-1ß are important pathological characteristics of OA. Laquinimod is a quinoline-3-carboxamide and a novel oral immunomodulatory compound in clinical use. However, whether laquinimod has a beneficial effect in OA is not known. In our research, we found that laquinimod could ameliorate IL-1ß-induced generation of ROS and improve mitochondrial function by increasing mitochondrial membrane potential (ΔΨm). Furthermore, treatment with laquinimod suppressed IL-1ß-induced production of TNF-α and IL-6. Notably, laquinimod prevented the degradation of type II collagen by inhibiting MMP-3 and MMP-13. Meanwhile, the presence of laquinimod attenuated the reduction in aggrecan by mediating ADAMTS-4 and ADAMTS-5. Mechanistically, laquinimod ameliorated IL-1ß-induced inflammation and degeneration of ECM by suppressing the activation of NF-κB. Taken together, our findings reveal that laquinimod possesses a beneficial effect against IL-1ß insults in human chondrocytes, implying an important role of laquinimod in OA.

Arthroscopic treatment for rotator cuff injury and frozen shoulder with concomitant rotator cuff injury: analysis of efficacy and factors influencing prognosis.

OBJECTIVE: To analyze the efficacy of arthroscopic treatment for patients with rotator cuff injuries and frozen shoulder combined with rotator cuff injuries and assess the factors influencing patient prognosis. METHODS: A retrospective analysis was performed on 85 patients who underwent arthroscopic surgery at Hanzhong Central Hospital between October 2016 and October 2021, including 42 patients treated for rotator cuff injuries alone (Group A), and 43 patients for frozen shoulder combined with rotator cuff injuries (Group B). Both groups underwent general anesthesia with controlled hypotension during surgery. Treatment outcomes, including shoulder joint functional scores, pain scores, shoulder joint range of motion, and muscle strength were assessed and compared between the two groups before treatment, as well as at 2 weeks and 2 months post-treatment. Quality of life was also evaluated and compared at 2 months post-treatment. Patients were categorized into good and poor prognosis groups based on their outcome, and factors influencing patient prognosis were analyzed. RESULTS: Before treatment, both groups exhibited relatively low shoulder joint function scores and external rotation angles, coupled with higher pain scores; however, these differences were not significant between groups (all P>0.05). The surgery duration for Group B was notably longer than that of Group A (P<0.05). Nevertheless, there was no significant variance in intraoperative blood loss between the two groups (P>0.05). After a 2-week treatment duration, both groups demonstrated a significant improvement in shoulder joint function score, pain score, and shoulder joint range of motion compared to baseline, but with no statistically significant intergroup differences. However, two months after the treatment, patients in Group A exhibited marked improvements in shoulder joint function score, pain score, shoulder joint range of motion, and overall quality of life compared to Group B (all P<0.05). Furthermore, the therapeutic efficacy in Group A was superior to that in Group B at the 2-month follow-up (P<0.05). Age, comorbid diabetes, metabolic disorders such as thyroid dysfunction, and the extent of shoulder cuff injury were identified as independent risk factors influencing prognosis. CONCLUSION: Arthroscopic treatment is effective for both frozen shoulder combined with rotator cuff injury and rotator cuff injury alone, with better outcomes observed in patients with rotator cuff injury only. This technique warrants further promotion.

Overexpression of lncRNA UCA1 promotes osteosarcoma progression and correlates with poor prognosis.

Long non-coding RNAs (lncRNAs) have been proved to play important roles in the tumorigenesis and development of several human malignancies. Our study aims to investigate the expression and function of lncRNA-UCA1 in osteosarcoma. lncRNA-UCA1 expression was detected in osteosarcoma tissues and cell lines by using qRT-PCR. Association between lncRNA-UCA1 levels and clinicopathological factors and patient's prognosis was analyzed. The roles of lncRNA-UCA1 in regulating osteosarcoma cell proliferation, apoptosis, migration, and invasion were evaluated in vitro. We found that lncRNA-UCA1 expression was upregulated in osteosarcoma tissues and cell lines. High lncRNA-UCA1 expression was significantly correlated with large tumor size, high tumor grade, positive distant metastasis, and advanced clinical stage. Multivariate regression analysis identified lncRNA-UCA1 overexpression as an independent unfavorable prognostic factor. lncRNA-UCA1 knockdown inhibited osteosarcoma cell proliferation, promoted cell apoptosis, and suppressed cell invasion and migration, whereas lncRNA-UCA1 overexpression showed opposite effects. These findings suggested that lncRNA-UCA1 may contribute to osteosarcoma initiation and progression, and would be not only a novel prognostic marker but also a potential therapeutic target for this disease.