Modified elastic intramedullary nail internal fixation for distal tibial metaphyseal junction fracture.

Objective: To investigate the application of modified elastic intramedullary nail and the outcomes between modified elastic stable intramedullary nailing and traditional elastic stable intramedullary nailing in children with distal tibial metaphyseal junction fracture. Methods: A retrospective study was conducted. From January 2018 to January 2021, a total of 36 children with distal tibial metaphyseal junction fracture were treated in our hospital. All of them were treated with closed reduction and elastic stable intramedullary nailing internal fixation. A total of 18 children were treated by modified elastic stable intramedullary nailing and 18 children were treated by traditional elastic stable intramedullary nailing. Postoperative imaging, clinical efficacy, and complications were analyzed. Results: The mean follow-up time was 20 (15-36) months in modified group and 22 (16-33) months in traditional group. There were no complications such as infection, loss of reduction, and unequal length of lower limbs in modified group while loss of reduction occurred in two cases in traditional group. In these two cases of loss of reduction, we preformed manual reduction and replacement of long leg casts, and there was no loss of reduction, and the patient achieved a good prognosis. In the last follow-up, American Orthopaedic Foot & Ankle Society score was used. In modified group, excellent outcome achieved in 17 cases, good outcome achieved in 1 case, and satisfactory therapeutic effect was achieved. In traditional elastic stable intramedullary nailing group, excellent outcome achieved in 14 cases, and good outcome achieved in 4 cases. There was no statistical difference in the scores between the two groups. Conclusion: It was concluded that modified elastic stable intramedullary nailing fixation is a safe and effective treatment.

Elastic Stable Intramedullary Nailing Versus Plate Internal Fixation for Pediatric Diaphyseal Femur Fractures: A Systematic Review and Meta-analysis.

Background: Elastic stable intramedullary nailing (ESIN) and plates are currently the main internal fixation for treating Pediatric Diaphyseal Femur Fractures (PDFF), and the optimal choice of internal fixation is controversial. The purpose of this meta-analysis is to compare the surgical outcomes and complications of the two fixation methods. Materials and Methods: MEDLINE, Embase, and the Cochrane Library were systematically searched for studies published up to March, 2023, that compared ESIN and plate fixation techniques for treating PDFF. Pooled analysis identified differences in surgical outcomes between ESIN and plate, mainly regarding surgical outcomes and postoperative complications, such as time at surgery, fracture healing time, blood loss and related complications. Results: We included 10 studies with 775 patients with PDFF in our review. Of these, 428 and 347 were treated with ESIN and Plate, respectively. In terms of postoperative complications, ESIN led to a shorter surgery time [MD = - 28.93, 95% CI (- 52.88 to - 4.98), P < 0.05], less blood loss [MD = - 66.94, 95% CI (- 87.79 to - 46.10), P < 0.001] and more fracture healing time [MD = 2.65, 95% CI (1.22-4.07), P < 0.001]. In terms of postoperative complications, ESIN led to fewer fections (RR = 0.77, 95% CI 0.37, 1.60, P = 0.48), fewer angulation deformities (RR = 0.80, 95% CI 0.35, 1.83, P = 0.60) and more prominent implants (RR = 3.36, 95% CI 1.88, 6.01, P < 0.001), more delayed unions (RR = 4.06, 95% CI 0.71, 23.06, P = 0.11). Conclusions: ESIN and Plate have similar rates of complications besides a prominent implant rate, while ESIN has a shorter period of operation and less intraoperative bleeding. Although both options are suitable, the results of this study support the use of ESIN rather than plates in the treatment of PDFF in terms of complication rates. In clinical applications, surgeons should choose the appropriate treatment method according to the actual situation.

Impact of wound complications in obese versus non-obese patients undergoing total hip arthroplasty: A meta-analysis.

This meta-analysis examined the post-operative wound effect of both obese and non-obese in total hip arthroplasty (THA) patients. To gather as complete an overview as possible, the researchers took advantage of 4 databases-PubMed, Embase, Cochrane Library and Web of Science-to conduct a critical assessment. Following the development of inclusion and exclusion criteria, the researchers evaluated the quality of each document. A total of 9 related trials were conducted to determine the 95% CI (CI) and OR using a fixed-effect model. The final meta-analyses were conducted with RevMan 5.3. Our findings indicate that there is no statistically significant benefit in terms of post-operative wound complications among obese and non-obese patients. Obese subjects had a significantly higher risk of injury than those without obesity (OR, 1.43; 95% CI, 1.04, 1.95, p = 0.03); obesity was also associated with a significantly higher risk of operative site infection than in non-obese subjects (OR, 1.96; 95% CI, 1.76, 2.18, p < 0.0001); and after surgery, there was also a significant increase in the risk of post-operative wound infections among obese subjects than in non-obese subjects (OR, 1.57; 95% CI, 1.34, 1.84, p < 0.0001). However, due to the small size of the cohort study in this meta-study, caution is required in the analysis. More randomized, controlled studies will be needed to validate these results.

MiR-217 regulates autophagy through OPG/RANKL/RANK in giant cell tumors.

BACKGROUND: Increasing evidence suggests that microRNAs (miRNAs) play a crucial role in cancer development and progression. Our previous study showed remarkably lower levels of miR-217 in GCT cells and tissues, and miR-217 re-expression inhibited the occurrence and development of GCT in vitro; however, the associated mechanisms remain unknown. Thus, this study aimed to explore the mechanisms underlying the proliferation inhibitory effect of miR-217 in GCT cells. METHODS: The proliferative potential of the GCT cells was measured with an MTT assay and BrdU straining. Changes in GCT cell migration and invasion was assessed by a transwell assay. Finally, Western blot and RT-PCR assays were employed to evaluate OPG/RANKL/RANK signaling pathway-related protein expression. RESULTS: The excessive upregulation of miR-217 markedly suppressed GCT cell proliferation and tumorigenesis both in vitro and in vivo. miR-217 overexpression could inhibit the OPG/RANKL/RANK signaling pathway in vitro and in vivo. Furthermore, ALP activity was significantly decreased in GCT cells following miR-217 treatment. Importantly, miR-217 could inhibit autophagy-related protein expression and autophagosome/autolysosome formation in GCT cells and tissues. CONCLUSION: These results suggest that miR-217 upregulation could inhibit the occurrence and development of GCT by blocking autophagy. These findings offer an effective therapeutic target to improve the survival rates of patients with CGT in the future.

Prognostic analysis and validation of diagnostic marker genes in patients with osteoporosis.

Backgrounds: As a systemic skeletal dysfunction, osteoporosis (OP) is characterized by low bone mass and bone microarchitectural damage. The global incidences of OP are high. Methods: Data were retrieved from databases like Gene Expression Omnibus (GEO), GeneCards, Search Tool for the Retrieval of Interacting Genes/Proteins (STRING), Gene Expression Profiling Interactive Analysis (GEPIA2), and other databases. R software (version 4.1.1) was used to identify differentially expressed genes (DEGs) and perform functional analysis. The Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression and random forest algorithm were combined and used for screening diagnostic markers for OP. The diagnostic value was assessed by the receiver operating characteristic (ROC) curve. Molecular signature subtypes were identified using a consensus clustering approach, and prognostic analysis was performed. The level of immune cell infiltration was assessed by the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm. The hub gene was identified using the CytoHubba algorithm. Real-time fluorescence quantitative PCR (RT-qPCR) was performed on the plasma of osteoporosis patients and control samples. The interaction network was constructed between the hub genes and miRNAs, transcription factors, RNA binding proteins, and drugs. Results: A total of 40 DEGs, eight OP-related differential genes, six OP diagnostic marker genes, four OP key diagnostic marker genes, and ten hub genes (TNF, RARRES2, FLNA, STXBP2, EGR2, MAP4K2, NFKBIA, JUNB, SPI1, CTSD) were identified. RT-qPCR results revealed a total of eight genes had significant differential expression between osteoporosis patients and control samples. Enrichment analysis showed these genes were mainly related to MAPK signaling pathways, TNF signaling pathway, apoptosis, and Salmonella infection. RT-qPCR also revealed that the MAPK signaling pathway (p38, TRAF6) and NF-kappa B signaling pathway (c-FLIP, MIP1ß) were significantly different between osteoporosis patients and control samples. The analysis of immune cell infiltration revealed that monocytes, activated CD4 memory T cells, and memory and naïve B cells may be related to the occurrence and development of OP. Conclusions: We identified six novel OP diagnostic marker genes and ten OP-hub genes. These genes can be used to improve the prognostic of OP and to identify potential relationships between the immune microenvironment and OP. Our research will provide insights into the potential therapeutic targets and pathogenesis of osteoporosis.

Methylprednisolone Inhibits Autophagy of Vascular Endothelial Cells in Rat Femoral Head Via PI3K/Akt/mTOR Pathway.

OBJECTIVE: To study the relationship between vascular endothelial cells (VEC) and autophagy, and its regulatory mechanism in steroid-induced avascular necrosis of the femoral head (SANFH). METHODS: In cell experiment, VEC were isolated and cultured from the femoral head of Sprague-Dawley rats and divided into three groups: blank control group (Ctrl), methylprednisolone group (MP), and methylprednisolone+mTOR-shRNA group (MP + shmTOR). The autophagy formation was observed by transmission electron microscope. The mRNA expression of PI3K, Akt, mTOR, Beclin1 and MAP1LC3 was detected by RT-PCR and the protein expression was detected by Western blot and immunofluorescence. Expression of the damage marker 6-keto-PGF1α was detected by the ELISA method. In vivo experiment, after establishing the model, the grouping method was the same as cell experiment. Autophagosomes were observed by same method, and the expression of related factors was detected by the same method in cell experiment. RESULTS: In the cell experiment, autophagosomes in the MP group were significantly lower than in the Ctrl group, and the autophagosomes in the MP + shmTOR group were intermediate between two groups (P < 0.05). The mRNA expression levels of PI3K, Akt and mTOR in the MP group were significantly higher than in the Ctrl group, while the MP+ shmTOR group presented intermediate levels between these groups (average gray value were 3837.90, 2996.30, 3005.60, F = 428.64, P < 0.05). MRNA expression levels of Beclin1 and MAP1LC3 in the MP group were significantly lower than that in Ctrl group (P < 0.05). The content of 6-keto-PGF1α in the MP + shmTOR group was higher than in the Ctrl group and lower than in the MP group at the evaluated time intervals (average absorbance value were 104.98, 206.83, 145.91, F = 352.83, P < 0.01). In vivo experiment, the content of 6-Keto-PGF1α in the hormone group increased as time went on; the mTOR-si group was higher than that in control group, but lower than that in the hormone group (P < 0.01). The mRNA expressions of Beclin1 and MAP1LC3 in the control group were higher than those in the hormone group, while the mRNA expressions of PI3K, Akt and mTOR were lower than those in the mTOR-si group (P < 0.05). CONCLUSION: The steroid inhibited the physiological protective effect of autophagy on SANFH by increasing the expression of PI3K/Akt/mTOR signaling pathway related factors and decreasing the expression of Beclin1 and MAP1LC3 in the femoral head VEC.

miR-30 inhibits the progression of osteosarcoma by targeting MTA1.

OBJECTIVES: MicroRNAs (miRNAs) have been considered as a new class of novel diagnostic and predictive biomarker in many diseases. However, there are few studies on miRNA in osteosarcoma (OS). This study aimed to investigate the roles of miR-30 on OS occurrence and development. METHODS: PCR was used to detect mRNA levels of miR-30 and MTA1 in cancer tissues, adjacent non-cancerous tissues from OS patients. Western blot was used to detect MTA1 protein expression in all tissues and cell lines (hFOb1.19,Saos-2, MG63, and U2OS). The correlation between miR-30 and MTA1 was predicted through bioinformatics software, and identified by a luciferase reporting experiment. In vitro, functional test detected the specific effects of miR-30 and MTA1 on the development of OS. RESULTS: miR-30 expression was significantly reduced, while the expression of MTA1 was increased in OS tissues and cells. Luciferase reporting experiment showed that miR-30 sponged MTA1 which was negatively correlated with miR-30 expression. Furthermore, rescue tests revealed that MTA1 restrained the functions of miR-30 on cell proliferation and migration of OS. CONCLUSION: Our finding showed that miR-30 modulated the proliferation and migration by targeting MTA1 in OS.

Overexpression of S100A1 in Osteosarcoma Inhibits Tumor Proliferation and Progression.

Background: Osteosarcoma is the most common primary malignant tumor of bone. Abnormal expression of S100A1 protein is closely related to the occurrence and development of malignant tumors. However, S100A1 in osteosarcoma has not been studied. Methods: All osteosarcoma tissues were collected from patients who received surgical therapy at the Affiliated Hospital of Inner Mongolia Medical University, China in 2020. QRT-PCR and western blot assays were used to detect the expression of S100A1 in osteosarcoma tissues and cells. The negative effect of S100A1 on osteosarcoma cell growth was confirmed by vitro and vivo experiments. Results: S100A1 inhibited the growth of osteosarcoma cells in vitro. Overexpression of S100A1 may inhibit the proliferation of osteosarcoma cells by preventing the activation of AKT signaling pathway by western blot assay. Finally, animal experiments confirmed that overexpression of S100A1 could inhibit the proliferation of osteosarcoma cells. Overexpression of S100A1 obtained better survival benefit in mice. Conclusion: Our findings provided a new insight to the treatment of osteosarcoma. It also raised the possibility that S100A1 could be used in targeted therapies for osteosarcoma.

Carcinoma-associated fibroblasts promote the proliferation and metastasis of osteosarcoma by transferring exosomal LncRNA SNHG17.

Cancer-associated fibroblasts (CAFs) serve as a predominant regulator in the tumor microenvironment. However, the crosstalk between CAFs and OS cells remains mostly unclear. Recent studies explored that long non-coding RNA (LncRNAs) involved in regulating osteosarcoma (OS) formation and development, but their functions in CAFs are unknown. Here, we first investigated the SNHG17 was upregulated in OS tissues and correlated with the poor prognosis through the integrating clinical data. We then evaluated the function of SNHG17 in vitro using the stable SNHG17-depleted OS cells. HOS cells with SNHG17 knocked down were performed to generate the OS xenograft model. Through immunohistochemistry assay and TUNEL apoptosis assay, the role of SNHG17 on OS development was assessed in vivo. We then examined the SNHG17 expression in exosomes derived from CAFs, normal fibroblasts (NFs), and tumor tissues from the OS clinical samples. The interaction among SNHG17, miR-2861, and MMP2 was predicted by bioinformatics analysis and identified by RIP and luciferase assays. The cell proliferation, migration, and apoptosis of SJSA-1 and HOS cells co-cultured with CAFs-derived exosomes were assessed by CCK-8 and colony formation assays. We found that SNHG17 was upregulated in the tumor tissues and presented a pro-tumorigenic effect on OS both in vitro and in vivo. It also was an essential exosomal cargo of CAFs and could affect OS cell proliferation and migration in vitro. CAFs-released exosomal SNHG17 acted as an essential molecular sponge for miR-2861 in OS cells. Moreover, MMP2 was a direct target of miR-2861 and was regulated by SNHG17. Overall, our findings identified that SNHG17 was an essential exosomal cargo of OS-related CAFs that contributes to proliferation and metastasis of OS, supporting the therapeutic potency of targeting the crosstalk between cancer cells and CAFs.

Sacral and thoracic chordoma with pulmonary metastases: A case report and review of the literature.

Chordoma is a sporadic type of cancer that affects the spine and is particularly challenging to treat due to the paucity of reported cases and scientific literature. In particular, primary chordomas affecting both the sacral and thoracic vertebrae are extremely rare. We herein report a rare case of chordoma in the sacral and thoracic vertebrae with pulmonary metastasis, along with a literature review. The objective of the present study was to explore treatment options and long-term outcomes in patients with metastatic chordoma. Posterior decompression was performed for the thoracic tumor, followed by extended resection of the sacral tumor. The symptoms of the patient were relieved after surgery, and the postoperative Nurick score decreased from grade 3 to grade 2, while the postoperative McCormick score was I. Therefore, complete chordoma excision and internal spinal fixation may effectively reduce tumor recurrence and metastasis.

MicroRNA­22 regulates autophagy and apoptosis in cisplatin resistance of osteosarcoma.

Osteosarcoma (OS) is a primary malignant tumor of bone tissue. Effective chemotherapy may improve the survival of patients with OS. MicroRNAs (miRs) serve significant roles in the regulatory function of tumorigenesis and chemosensitivity of different types of cancer. miR­22 has been revealed to inhibit the proliferation and migration of OS cells, as well as increasing their sensitivity to cisplatin (CDDP). The mechanisms of action behind the functions of miR­22 in OS drug resistance require investigation. Therefore, in the present study, the human OS cell lines (MG­63, U2OS, Saos2 and OS9901) and a drug­resistant cell line (MG­63/CDDP) were cultured. Cell proliferation, apoptosis and autophagy assays were performed to investigate the proliferation, apoptosis and autophagy of cell lines transfected with miR­22 mimic. Reverse transcription­quantitative polymerase chain reaction and western blot analysis were performed to investigate the expression levels of associated genes. The results revealed that miR­22 inhibited the proliferation of MG­63 cells and MG­63/CDDP cells, and enhanced the anti­proliferative ability of CDDP. miR­22 induced apoptosis and inhibited autophagy of MG­63 cells and MG­63/CDDP cells. Apoptosis­related genes, including caspase­3 and Bcl­2­associated X protein were upregulated, while B­cell lymphoma­2 was downregulated in both cell lines transfected with the miR­22 mimic. Autophagy protein 5, beclin1 and microtubules­associated protein 1 light chain 3 were downregulated in both cell lines transfected with miR­22 mimic. Furthermore, the in vitro and in vivo expression levels of metadherin (MTDH) in the OS/OS­CDDP­resistant models were downregulated following transfection with the miR­22 mimic. Therefore, the results of the present study suggested that miR­22 promoted CDDP sensitivity by inhibiting autophagy and inducing apoptosis in OS cells, while MTDH may serve a positive role in inducing CDDP resistance of OS cells.

The use of a transolecranon pin joystick technique in the treatment of multidirectionally unstable supracondylar humeral fractures in children.

Multidirectionally unstable supracondylar humeral fractures cause severe instability in both flexion and extension movements. The traditional closed reduction often fails to overcome this lack of stability. The aim of this study is to use a closed reduction technique with a transolecranon pin to achieve temporary stability. From 35 pediatric multidirectionally unstable supracondylar humeral fractures hospitalized between March 2012 and March 2018 at our hospital, 23 fractures (65.7%) were treated with closed reduction and percutaneous pinning (CRPP) (group 1) and the remaining twelve fractures (34.3%) were treated utilizing a transolecranon pin joystick technique of CRPP (group 2). Both groups were followed over 16 weeks. The outcomes of our analysis included surgical time, times of fluoroscopy, Baumann angle, postoperative range of motion and complications. The surgical time and times of fluoroscopy were significantly shorter for patients in group 2 when compared with group 1 (P < 0.05). All cases showed restoration of the normal anterior humeral line-capitellar relationship. However, the quality of reduction on the anteroposterior radiographic view was significantly better for patients in group 2 than that of group 1 (P < 0.05). No immediate postoperative complications were observed. The range of motion was similar in both groups during the last follow-up appointment. A transolecranon pin is a safe and effective method for closed reduction of multidirectionally unstable supracondylar humeral fractures in children. The joystick technique can shorten surgical time and improve quality of reduction with no increasing risk of complications. Level of evidence: level III.

MicroRNA­22 mediates the cisplatin resistance of osteosarcoma cells by inhibiting autophagy via the PI3K/Akt/mTOR pathway.

Osteosarcoma (OS) is the most common primary malignant tumor of the bone affecting children and adolescents. Chemotherapy is now considered as a standard component of OS treatment, not only for children, but also for adults. However, chemoresistance continues to pose a challenge to therapy. Inhibition of autophagy has been demonstrated to decrease chemoresistance in OS. Moreover, microRNA­22 (miR­22) inhibits autophagy, leading to an improvement in the sensitivity of cisplatin (CDDP) in OS. The aim of the present study was therefore to investigate whether miR­22 could mediate the CDDP resistance of OS cells by inhibiting autophagy via the phosphoinositide 3­kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway. Cell proliferation assay, LC3 flow cytometry assay and monodansylcadaverine staining in MG63 cells and CDDP resistance cells (MG63/CDDP) were performed to explore to role of miR­22 and CDDP in OS chemoresistance. Inoculation of tumor cells in an in vivo model, reverse transcription­quantitative PCR (RT­qPCR) assay, western blot analysis, and immunohistochemistry analysis were performed to investigate the role of miR­22 and CDDP in the PI3K/Akt/mTOR pathway as it is affected by autophagy. The results revealed that miR­22 inhibited the proliferation of MG63 and MG63/CDDP cells, and enhanced the anti­proliferative ability of CDDP in vivo and in vitro. miR­22 mediated the CDDP resistance of OS cells by inhibiting autophagy and decreasing CDDP­induced autophagy via downregulation of the expression of PI3K, Akt, and mTOR at the mRNA level, and the expression of PI3K, phosphorylated (p)­Akt, and p­mTOR at the protein level. It was also convincingly demonstrated that miR­22 mediates the CDDP resistance of OS by inhibiting autophagy via the PI3K/Akt/mTOR pathway. Furthermore, in the MG63 cells that were affected by CDDP, the role of miR­22 was shown to be similar to that of the investigated inhibitor of PI3K (wortmannin) in terms of regulating the PI3K/Akt/mTOR pathway, and wortmannin could also promote the effect of miR­22. Interestingly, CDDP was demonstrated to induce autophagy by inhibiting the PI3K/Akt/mTOR pathway, whereas the pathway was upregulated in the state of chemoresistance. In conclusion, downregulation of the PI3K/Akt/mTOR pathway was shown to assist in the process of preventing chemoresistance.

Mechanism of Methylprednisolone-Induced Primary Cilia Formation Disorder and Autophagy in Osteoblasts.

OBJECTIVE: To study the role of primary cilia formation disorder and osteoblasts autophagy in the pathogenesis of steroid-induced avascular necrosis of the femoral head (SANFH). METHODS: Osteoblasts were isolated from rabbit bones and treated with 1 µM Methylprednisolone for 0, 12, 24, 48, and 72 h. The Beclin1, MAP1LC3, Atg-5, Atg-12, IFT20 and OFD1 mRNAs and proteins were detected by PCR and Western blotting, and their correlation was statistically analyzed. The lengths of osteoblast cilia were measured under a laser confocal microscope, and the autophagy flux was tracked by transfecting the osteoblasts with GFP-RFP-LC3 lentivirus. RESULTS: Methylprednisolone significantly upregulated Beclin1, MAP1LC3, Atg-5, Atg-12 and OFD1 mRNAs and proteins in a time-dependent manner, and decreased that of IFT20 (P < 0.05). In addition, the autophagy flux in the osteoblasts also increased and the ciliary length decreased in a time-dependent manner after Methylprednisolone treatment. The length of the cilia were 5.46 ± 0.11 um at 0 h, 4.08 ± 0.09 um at 12 h, 3.07 ± 0.07 um at 24 h, 2.31 ± 0.10 um at 48 h, and finally 1.15 ± 0.04 um at 72 h. Methylprednisolone treatment also affects primary cilium numbers in cultures, for 0 to 72 h. The autophagy regulatory genes, Beclin1, MAP1LC3, Atg-5 and Atg-12, were found to be negatively correlated with IFT20, with an average correlation coefficient of -0.81. A negative correlation was also found between OFD1 and IFT20, with an average correlation coefficient of -0.53. CONCLUSION: Methylprednisolone inhibits primary cilia formation and promotes autophagy, which could be the pathological basis of SANFH. The exact regulatory mechanism needs to be further studied in vivo.

Influence of MicroRNA-141 on Inhibition of the Proliferation of Bone Marrow Mesenchymal Stem Cells in Steroid-Induced Osteonecrosis via SOX11.

OBJECTIVE: To investigate whether miR-141 and the sex determination region of Y chromosome box 11 (SOX11) play roles in steroid-induced avascular necrosis of the femoral head (SANFH), and to explore whether miR-141 could target SOX11 to influence the proliferation of bone marrow mesenchymal stem cells (BMSC). METHODS: Bone marrow mesenchymal stem cells (BMSC) were isolated and cultured from 4-week-old Sprague Dawley rats. A flow cytometry assay was performed to identify BMSC. BMSC were divided into two groups: a control group and a dexamethasone (DEX) group. BMSC were transfected by miR-141 mimic, miR-141 inhibitor, and SOX11. Real-time polymerase chain reaction (PCR) assay was performed to investigate the mRNA expression of miR-141 and SOX11. The results were used to determine the effect of transfection and to verify the expression in each group and the association between miR-141 and SOX11. Luciferase reporter assay revealed the targeted binding site between miR-141 and the 3'-untranslated region of SOX11 mRNA. MTT assays were performed to investigate the proliferation of BMSC in the miR-141 mimic, miR-141 inhibitor, and SOX11 groups. RESULT: The results of the flow cytometry assay suggested that cells were positive for CD29 and CD90 while negative for CD45. This meant that the isolated and cultured cells were not hematopoietic stem cells. In addition, cell transfection was successful based on the expression of miR-141 and SOX11. According to the results of real-time PCR assay, the mRNA expression of miR-141 in SANFH was upregulated (4.117 ± 0.042 vs 1 ± 0.027, P < 0.001), while SOX11 was downregulated (0.611 ± 0.055 vs 1 ± 0.027, P < 0.001) compared with the control group. Based on the results of the luciferase experiment, MiR-141 could directly target the expression of SOX11. Inhibition of miR-141 could upregulate the expression of SOX11 (2.623 ± 0.220 vs 1 ± 0.095, P < 0.001) according to the results of a real-time PCR assay. MiR-141 inhibited the proliferation of BMSC (0.618 ± 0.092 vs 1.004 ± 0.082, P < 0.001), while suppression of miR-141 increased the proliferation of BMSC (0.960 ± 0.095 vs 0.742 ± 0.091, P < 0.001). Furthermore, according to the results of the MTT assay, SOX11 promoted the proliferation of BMSC (1.064 ± 0.093 vs 0.747 ± 0.090, P < 0.001). CONCLUSION: MiR-141 inhibited the proliferation of BMSC in SANFH by targeting SOX11. Inhibition of miR-141 upregulated the expression of SOX11 and promoted the proliferation of BMSC. MiR-141 and SOX11 could be new targets for investigating the mechanism of SANFH.

Roles of microRNA-22 in Suppressing Proliferation and Promoting Sensitivity of Osteosarcoma Cells via Metadherin-mediated Autophagy.

OBJECTIVE: To analyze the effect of microRNA-22 on autophagy and proliferation and to investigate the underlying molecular mechanism of osteosarcoma cell chemotherapy sensitivity. METHODS: MG-63 cells were divided into four groups, including a control group, a negative control (NC) group, a cisplatin group, and a cisplatin + miR-22 group. Proliferation of MG-63 cells that had been treated with cisplatin and transfected with miR-22 mimics was determined using MTT assay and colony formation assay. We assessed the degree of autophagy using flow cytometry through cellular staining of the autophagy lysosomal marker monodansylcadaverine (MDC). The effect of microRNA-22 on autophagy was observed along with the expression levels of Beclin1, LC3, metadherin (MTDH) and ATG5 by western blot and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Luciferase reporter assay revealed the targeted binding site between miR-22 and the 3'-untranslated region (3'-UTR) of MTDH mRNA. Western blot and qRT-PCR were used to explore the level of MTDH in the control group, the NC group, the cisplatin group, and the miR-22 group for 6, 12, and 24 h. RESULTS: In the in vitro study, the MTT results indicated that the MG-63 cells with overexpression of miR-22 exhibited a significant decline in the proliferation capacity compared with the control group (0.513 ± 0.001, P < 0.0005). Similar to the MTT results, MG-63 cells that were transfected with miR-22 mimic (101.0 ± 10.58) formed fewer colonies compared with the cisplatin group (129.7 ± 4.163). MDC staining revealed that miR-22-overexpressing osteosarcoma (OS) cells treated with cisplatin showed a significant decrease in the expression of autophagy (7.747 ± 0.117, P < 0.0001). Our data revealed that miR-22 could regulate not only autophagy but also proliferation in the chemosensitivity of osteosarcoma cells. We found that miR-22 sensitized osteosarcoma cells to cisplatin treatment by regulating autophagy-related genes. In addition, Luciferase Reporter Assay revealed that miR-22 negatively regulated autophagy through direct targeting of MTDH. We performed western blot analysis to detect the MTDH expression level. The results revealed that the overexpression of miR-22 obviously decreased the expression of MTDH (1.081 ± 0.023, P < 0.001). CONCLUSION: Inhibition of miR-22 ameliorated the anticancer drug-induced cell proliferation decrease in osteosarcoma cells. MTDH was identified as the miR-22 target in OS cells and MTDH-triggered autophagy played a key function in the miR-22-associated chemotherapy sensitivity.

MMP-8 single-nucleotide polymorphisms are related to ankylosing spondylitis in Chinese Han population.

Ankylosing spondylitis (AS) is an extreme form of inflammatory arthritis which always leads to bony fusion of vertebral and chronic pain of back. A lot of genes including interleukin, matrix metalloproteinases (MMPs), and endoplasmic reticulum aminopeptidase were found associated with AS. MMP family members were involved in the autoimmune disease and orthopedic diseases such as rheumatoid arthritis and osteoarthritis, while few studies concentrated on the correlation between single-nucleotide polymorphisms (SNPs) in MMP and AS. In addition, there is no report on the relationship between MMP-8 and AS. To investigate the association between SNPs in MMP-8 and AS, we recruited 268 patients with AS and 654 healthy people to conduct a case-control study. Five SNPs including rs3740938, rs2012390, rs1940475, rs11225394, and rs11225395 of MMP-8 gene were genotyped. It was found rs3740938 of MMP-8 was associated with an increased risk of AS under the dominant model and additive model after adjustment for gender and age by performing logistic regression analysis (odds ratio [OR] = 1.49, 95% confidence interval [CI] = 1.02-2.18, P = .038; OR = 1.37, 95% CI = 1.01-1.87, P = .042, respectively). Moreover, haplotype "GGTCA" was associated with an increased risk of AS without adjustment for age and gender (OR = 1.75, 95% CI = 1.05-2.92, P = .032), while no positive result was found after adjustment for age and gender. Based on our results, our study indicates significant association between SNPs of MMP-8 and AS risk in a Chinese Han population and these results provide the first evidence that MMP-8 is correlated with AS.