Actin cytoskeleton aggregation involves the water channel protein aquaporin 1-mediated human chondrocyte degeneration.

Water metabolism and actin cytoskeleton remoulding act as essential characters in the process of osteoarthritis (OA). However, the relation between water channel protein aquaporin 1 (AQP1) and actin filament during chondrocytes (CHs) degeneration is not evident. Therefore, the present study aimed to evaluate the role of actin remoulding in the AQP1 mediated CHs degeneration. Primary CHs were collected from human hip cartilage and were degenerated from long-time monolayer culture or IL-1ß stimulation. Besides, the CHs were transfected with AQP1­specific siRNA or vectors to mediate the AQP1 gene expression. The potent inhibitor of actin polymerization Cytochalasin D was also supplemented during culture. RT-PCR was performed to determine the relative gene expression. AQP1 and F-actin fluorescence staining were performed to determine the AQP1 and F-actin organization. Moreover, the cell area and viability were also analyzed. AQP1 and F-actin organization were both increased during seven days' CHs culture or three days' IL-1ß stimulation. Silencing of AQP1 prevented the cell area spreading and degenerated phenotype of CHs with suppression of F-actin aggregation in both natural or IL-1ß-caused inflammatory-related degeneration. Besides, upregulating the AQP1 in the CHs via gene editing promoted the cell area spreading, and F-actin accumulation, and accelerated the CHs degeneration, which can be alleviated by Cytochalasin D treatment. These findings suggested that AQP1-mediated human CHs degeneration is related to F-actin aggregation.

Anterior debridement combined with autogenous iliac bone graft fusion for the treatment of lower cervical tuberculosis: a multicenter retrospective study.

BACKGROUND: This study aimed to analyze the clinical efficacy of one-stage anterior debridement of lower cervical tuberculosis using iliac crest bone graft fusion and internal fixation. MATERIALS AND METHODS: A retrospective analysis was performed on 48 patients with lower cervical tuberculosis admitted to multiple medical centers from June 2018 to June 2021. Among them, 36 patients had lesions involving two vertebrae and 12 patients had lesions involving more than three vertebrae. All patients were treated with quadruple antituberculosis drugs for more than 2 weeks before the operation, and then treated with one-stage anterior debridement and autogenous iliac bone graft fusion combined with titanium plate internal fixation. After the operation, antituberculosis drugs were continued for 12-18 months. The patients were followed-up to observe the improvement in clinical symptoms, bone graft fusion, Cobb angle, visual analog score (VAS), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), wound healing, and neurological function. RESULTS: The patients were followed-up for 13-43 months, with an average of 21.46 ± 1.52 months. The clinical symptoms significantly improved after the operation. The bone graft was completely fused in all patients, and the bone fusion time was 3-6 months, with an average of 4.16 ± 0.47 months. At the last follow-up, the Cobb angle, VAS, ESR, and CRP level were significantly lower than those before surgery (P < 0.05). None of the patients had loosening, detachment, or rupture of the internal fixation, and no recurrence occurred. All surgical incisions healed in one stage without infection or sinus formation. The preoperative Frankel neurological function classification was grade B in 7 cases, grade C in 13, grade D in 18, and grade E in 10. At the last follow-up, 8 cases recovered to grade D and 40 recovered to grade E. CONCLUSIONS: For patients with lower cervical tuberculosis, based on oral treatment with quadruple antituberculosis drugs, direct decompression through anterior debridement, followed by autologous iliac bone graft fusion combined with internal fixation can completely remove tuberculosis foci, rebuild the stability of the cervical spine, and obtain good clinical efficacy. Level of evidence Level 3.

Minimally invasive plate osteosynthesis with a locking compression plate is superior to open reduction and internal fixation in the management of the proximal humerus fractures.

BACKGROUND: The use of minimally invasive plate osteosynthesis (MIPO) via anterolateral deltoid splitting has good outcomes in the management of proximal humerus fractures. While using this approach has several advantages, including minimal soft tissue disruption, preservation of natural biology and minimal blood loss, there is an increased risk for axillary nerve damage. This study compared the advantages and clinical and radiological outcomes of MIPO or open reduction and internal fixation (ORIF) in patients with proximal humerus fractures. METHODS: A matched-pair analysis was performed, and patient groups were matched according to age (±3 years), sex and fracture type. Forty-three pairs of patients (average age: MIPO, 63 and ORIF, 61) with a minimum follow-up of 12 months were enrolled in the study group. The patients were investigated radiographically and clinically using the Constant score. RESULTS: The MIPO technique required less surgery time and caused less blood loss compared to ORIF (p < 0.01). In addition, MIPO required a smaller incision, resulted in less scarring, and was cosmetically more appealing and acceptable to female patients than ORIF. Following MIPO, patients had better functional results at 3 and 6 months, with better outcomes, less pain, higher satisfaction in activities of daily living, and a higher range of motion when compared to ORIF (p < 0.05). Fracture configuration, according to the AO/ASIF(Association for the Study of Internal Fixation) fracture classification, did not significantly influence the functional results. The complication rate was comparable between both groups. CONCLUSION: The use of MIPO with a locking compression plate in the management of proximal humerus fractures is a safe and superior option compared to ORIF.

Effect of microRNA-101 on proliferation and apoptosis of human osteosarcoma cells by targeting mTOR.

Studies have proved that microRNA-101 (miR-101) functions as a tumor suppressor and is associated with growth and apoptosis of various human cancers. However, the role of miR-101 in osteosarcoma and the possible mechanism by which miR-101 affects the tumor growth and apoptosis have not been fully elucidated. In this study, we found that the expression of miR-101 was down-regulated in osteosarcoma tissues and Saos-2 cell line as compared with that in adjacent non-neoplastic bone tissues and the osteoblastic cell line. To better characterize the role of miR-101 in osteosarcoma, we used a gain-of-function analysis by transfecting human osteosarcoma cell line Saos-2 with chemically synthesized miR-101 mimics. The results showed that overexpression of miR-101 inhibited the proliferation and promoted the apoptosis of Saos-2 cells. Meanwhile, bioinformatic analysis demonstrated that mTOR gene was a direct target of miR-101. Overexpression of miR-101 significantly decreased the expression of mTOR at both mRNA and protein levels in Saos-2 cells, consequently inhibiting Saos-2 cells proliferation and promoting cells apoptosis in an mTOR-dependent manner. Taken together, these data suggest that miR-101 may act as a tumor suppressor, which is commonly downregulated in both osteosarcoma tissues and cells. mTOR plays an important role in mediating miR-101 dependent biological functions in osteosarcoma. Reintroduction of miR-101 may be a novel therapeutic strategy by down-regulating mTOR expression.

Cinobufagin inhibits tumor progression and reduces doxorubicin resistance by enhancing FOXO1-mediated transcription of FCGBP in osteosarcoma.

ETHNOPHARMACOLOGICAL RELEVANCE: Cinobufagin (Huachansu), an aqueous extract from the dried skin of the toad Bufo bufo gargarizans Cantor (frog skin), is a biologically active ingredient of a traditional Chinese medicine cinobufacini that can treat multiple bone pathological conditions such as bone pain, bone tumors, and osteosarcoma. AIM OF THE STUDY: The study aimed to explore the roles and molecular mechanisms of cinobufagin underlying osteosarcoma development and doxorubicin (ADR) resistance. MATERIALS AND METHODS: Cell viability, migration, and invasion were examined by CCK-8, wound healing, and Transwell invasion assays, respectively. RNA sequencing analysis was performed in MNNG/HOS cells treated with or without cinobufagin. The relationships of cinobufagin, forkhead box O1 (FOXO1), and Fc fragment of IgG binding protein (FCGBP) were examined by luciferase reporter, immunofluorescence (IF), RT-qPCR, and chromatin immunoprecipitation (ChIP) assays together with weighted gene co-expression network analysis (WGCNA) analysis. Epithelial-mesenchymal transition (EMT) marker levels were examined through the Western blot assay. The function and molecular basis of cinobufagin in osteosarcoma were further investigated by mouse xenograft experiments. RESULTS: Cinobufagin reduced cell viability, weakened ADR resistance, and inhibited cell migration/invasion/EMT in osteosarcoma cells. Cinobufagin enhanced FOXO1-mediated transcription of downstream genes including FCGBP. FCGBP knockdown partly abrogated the effect of cinobufagin on osteosarcoma cell development. Cinobufagin inhibited the growth of mouse osteosarcoma xenografts in vivo. Cinobufagin reduced the expression of Ki-67 and MMP9 and facilitated caspase-3 expression in osteosarcoma xenografts. CONCLUSION: Cinobufagin suppressed tumor progression and reduced ADR resistance by potentiating FOXO1-mediated transcription of FCGBP in osteosarcoma.

Posttranscriptional inhibition of γ-adducin promotes the proliferation and migration of osteosarcoma cells.

OBJECTIVE: The expression of cytoskeleton-related protein γ-adducin (ADD3) was abnormally reduced in some tumors. Functional experiments demonstrated that it could inhibit the malignant progression of lung cancer and glioma, whereas the involvement of ADD3 in osteosarcoma was not clear. This study aimed to investigate the role of ADD3 in osteosarcoma and its upstream regulatory mechanisms. METHODS: ADD3 was knocked down by siRNA transfection and the expression level of ADD3 was determined using quantitative real-time PCR assay and Western blot. CCK-8 assay and colony formation were performed to detect the capacity of cell proliferation. Transwell assay and PI and Annexin V-FITC staining were used to determine cell migration and apoptosis, respectively. Luciferase reporter experiment was performed to investigate the interaction between ADD3 and miR-23b-3p. RESULTS: Based on gene silencing assays, we showed that knockdown of ADD3 suppressed apoptosis and promoted the proliferation and migration of osteosarcoma cells, revealing inhibitory effects of ADD3 in osteosarcoma. Luciferase reporter gene assays confirmed that miR-23b-3p could bind to the 3'-UTR of ADD3. Upregulation of miR-23b-3p not only inhibited the expression of ADD3, but also released the tumor suppressive role of ADD3 on the proliferation and migration of osteosarcoma cells. CONCLUSIONS: Our study found that ADD3 functioned as a tumor suppressor gene during osteosarcoma development. The abnormal upregulation of miR-23b-3p targeted the expression of ADD3 and resulted in accelerated osteosarcoma cell proliferation and migration. Thus, the miR-23b-3p/ADD3 axis contributes to the development of osteosarcoma and ADD3 is a key driver of malignancy.

Association between functional variants in BIRC5/survivin gene 3' untranslated region and mRNA expression in lymphoblastoid cell lines.

Baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5)/survivin genetic microRNA (miRNA) binding site variants in the 3' untranslated region (3'UTR) are known to be significantly associated with cancer risk. However, the roles of genetic variants in BIRC5/survivin gene 3'UTRs and post-transcriptional regulation have not been elucidated. In the present study, we revealed that rs1042489, rs1042542, rs17882360, rs2239680, rs2661694 and rs4789560 in the BIRC5/survivin 3'UTR have potential miRNA binding sites using bioinformatics analysis. However, only rs1042489 was significantly associated with BIRC5/survivin mRNA expression in lymphoblastoid cell lines (P=0.030); rs1042489 may be a putative variant mediating the post-transcriptional regulation of the target BIRC5/survivin gene. An in-depth understanding of how 3'UTR variants regulate BIRC5/survivin activity is expected to pave the way to targeting the BIRC5/survivin pathway in cancer therapy.