OBJECTIVES: To investigate the regulatory mechanism of aurora kinase B (AURKB) for promoting malignant phenotype of osteosarcoma cells. METHODS: HA-Vector or HA-AURKB was transfected in 293T cells to identify the molecules interacting with AURKB using immunoprecipitation combined with liquid chromatography-tandem mass spectrometry followed by verification with co-immunoprecipitation and Western blotting. In cultured osteosarcoma cells with lentivirus-mediated RNA interference of AURKB or DHX9 or their overexpression, the changes in cell proliferation, migration, and invasion activities were observed with EDU and Transwell assays. Mechanistic analysis was performed using Co-IP and in vivo ubiquitination experiments to detect the interaction between AURKB and DHX9 and the phosphorylation and ubiquitination levels of DHX9. Western blotting was used to detect the effect of AURKB and DHX9 on activation of nuclear factor-κB (NF-κB) signaling. RESULTS: AURKB was highly expressed in osteosarcoma cell lines, and in osteosarcoma 143B cells, AURKB silencing significantly reduced cell proliferation, migration and invasion abilities. Interactions between AURKB and DHX9 were detected, and they were both highly expressed in osteosarcoma tissues; silencing AURKB reduced the protein expression of DHX9, and AURKB overexpression increased DHX9 phosphorylation. Silencing AURKB did not significantly affect the transcription and translation of DHX9 but accelerated its degradation and ubiquitination. Overexpression of DHX9 effectively reversed the effects of AURKB silencing on IKBα protein and phosphorylated p65, promoted nuclear translocation of p65 to activate the NF-κB signaling pathway, and enhanced the proliferation, migration, and invasion abilities of cultured osteosarcoma cells. CONCLUSIONS AURKB overexpression promotes the malignant phenotype of osteosarcoma cells by activating the NF-κB signaling pathway via regulating DHX9.
Humans ; Osteosarcoma/genetics* ; Cell Proliferation ; NF-kappa B/metabolism* ; Signal Transduction ; Cell Line, Tumor ; Cell Movement ; DEAD-box RNA Helicases/genetics* ; Aurora Kinase B/genetics* ; Phenotype ; Bone Neoplasms/genetics* ; Neoplasm Invasiveness ; Phosphorylation ; Neoplasm Proteins

After workers suffer electric shock, the ankylosis and contraction of muscle groups around the shoulder joint are more likely to lead to posterior dislocation and fracture, of which 80% are complicated with reverse Hill-Sachs injury of humeral head. This paper reports a case of bilateral posterior dislocation of shoulder joint combined with Hill-Sachs injury caused by electric shock in the Department of Orthopedics, Affiliated Huzhou Hospital, Zhejiang University School of Medicine in August 2020. The diagnosis of left posterior shoulder dislocation was clear, and the diagnosis of right posterior shoulder dislocation was missed. The patient successfully reconstructed the stability of the shoulder joint by actively performing shoulder arthroscopic surgery to repair the joint capsule. After 6 months of follow-up, there was no further dislocation and the function was good.

After workers suffer electric shock, the ankylosis and contraction of muscle groups around the shoulder joint are more likely to lead to posterior dislocation and fracture, of which 80% are complicated with reverse Hill-Sachs injury of humeral head. This paper reports a case of bilateral posterior dislocation of shoulder joint combined with Hill-Sachs injury caused by electric shock in the Department of Orthopedics, Affiliated Huzhou Hospital, Zhejiang University School of Medicine in August 2020. The diagnosis of left posterior shoulder dislocation was clear, and the diagnosis of right posterior shoulder dislocation was missed. The patient successfully reconstructed the stability of the shoulder joint by actively performing shoulder arthroscopic surgery to repair the joint capsule. After 6 months of follow-up, there was no further dislocation and the function was good.