Upregulation of miR-21 was associated with poor clinicopathological characteristics. It is used as a marker of poor prognosis in patients with osteosarcoma.

Background Spinal metastasis is a major challenge in patients with advanced lung cancer, but the mechanisms in the organotropism of metastasis are still unclear. Adipose-derived mesenchymal stem cells (ADSCs) exhibit cancer-promoting properties that influence the tumour microenvironment; however, there is no research on ADSCs from epidural fat thus far. Methods In this study, we isolated and identified ADSCs from epidural adipose tissue for the first time. We examined the activation of epidural ADSCs treated with lung cancer cell-conditioned medium by immunohistochemistry, western blot and qRT-PCR assays. The expression of interleukin (IL)-6 family cytokines in the supernatants of ADSCs were evaluated by enzyme-linked immunosorbent assay. The effects of epidural ADSCs on the growth and invasion of lung cancer cells were evaluated with the CCK-8 and Transwell assays. The expression of signal transducer and activator of transcription 3 (STAT3), matrix metalloprotease and epithelial-mesenchymal transition markers were measured by western blot assays. Results Our results showed that ADSCs treated with lung cancer cell-conditioned medium expressed higher levels of the myofibroblast marker α-smooth muscle actin and fibroblast activation protein than ADSCs cultured alone. Then, we found that lung cancer cells induced ADSCs to secrete high levels of IL-6 family cytokines and activate the STAT3 signalling pathway. Moreover, activated epidural ADSCs exhibited the ability to promote lung cancer cell proliferation and invasion by elevating matrix metalloprotease expression and epithelial-mesenchymal transition in cancer cells. Furthermore, blocking IL-6 can counteract the differentiation and tumour-promoting effects of ADSCs. Conclusion Our results suggest that ADSCs respond to lung cancer cells and are involved in the crosstalk between primary tumours and pre-metastatic niches in epidural fat. Electronic supplementary material The online version of this article (10.1186/s13287-019-1280-3) contains supplementary material, which is available to authorized users.

Introduction: Irreducible atlantoaxial dislocation (IAAD) has been challenging for spine surgeons. Various methods have been used to treat IAAD, but no consensus has been reached. This study aimed to retrospectively analyze the efficacy of anterior submandibular retropharyngeal release and posterior reduction and fixation for IAAD. Methods: From March 2007 to May 2015, 13 patients diagnosed with IAAD underwent anterior submandibular retropharyngeal release and sequential posterior reduction and fixation. The operation time, blood loss, postoperative complications, and Japanese Orthopaedic Association (JOA) scores were retrospectively recorded. Results: The surgeries were accomplished successfully. The mean operative time was about 3.8 h. The mean estimated blood loss was about 130 mL. The patients experienced postoperative pharyngeal pain. Only one patient had a vague voice and increased oral discharge postoperatively. At the final follow-up, JOA scores had significantly increased ( p < 0.05), and all the patients had solid bony fusion. Conclusion: The present study reinforces the efficacy and safety of anterior submandibular retropharyngeal release and posterior reduction and fixation for IAAD. It can achieve satisfactory clinical outcomes and is safe for experienced spine surgeons.

We suggest that decompression surgery should be carried out as early as possible for patients with early spinal myelopathy or paraplegia caused by a calcified protruded disc.

Background: Atlantoaxial subluxation (AAS) is a not rare abnormality between the atlas (C1) and axis (C2). For AAS patients with persistent neck pain and neurologic symptoms, surgical intervention is a good choice. Nevertheless, there were still few reports about the use of intraoperative skull traction and different fixation methods in treatment of AAS. Methods: From January 2012 to December 2018, a total of 86 cases were admitted to our hospital and diagnosed as AAS. All the patients received atlantoaxial reduction with the help of intraoperative skull traction and C1-C2 fixation. Clinical and radiological parameters were collected through chart review. Results: There were 86 cases included in this study. The mean operative time was 153.9 ± 73.9 min, and the mean amount of intraoperative blood loss was 219.1 ± 195.6 ml. 81 patients underwent posterior reduction, internal fixation and fusion. 5 patients underwent anterior release, followed by posterior internal fixation and fusion. 82 patients got satisfactory postoperative outcomes while complications occurred in 4 patients. Significant neurologic improvement was observed in these patients. Bone fusion was achieved on the midline sagittal reconstructed CT images at the latest follow-up in all these patients except 1 case. All the patients were followed up for 34.84 ± 15.86 months at average (range 12-60 months). The mean ADI value was 7.55 ± 1.67 mm at average preoperatively, and improved to 4.03 ± 1.21 mm postoperatively, and to 4.21 ± 0.99 mm at the latest follow-up. The mean A-A angle was 15.48 ± 9.82 degrees at average preoperatively, and improved to 21.61 ± 10.43 degrees postoperatively, and to 19.73 ± 8.13 degrees at the latest follow-up. The mean A-A height was 35.61 ± 7.66 mm at average preoperatively, and improved to 40.08 ± 8.5 mm postoperatively, and to 38.83 ± 6.97 mm at the latest follow-up. There were complications in 4 patients, including pedicle misplacement, pedicle screw fracture, infection and one death. Conclusion: Intraoperative skull traction can effectively facilitate the surgical procedures for ASS caused by different etiologies. Further research will be needed to investigate the safety and effectiveness of this method in the future.