No abstract

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), one of the first found cancer-associated long noncoding RNAs (lncRNAs), involves in the development and progression of many types of tumors. An aberrant expression of MALAT1 was observed in hepatocellular carcinoma, cervical cancer, breast cancer, ovarian cancer, and colorectal cancer. However, the exact effects and molecular mechanisms of MALAT1 in osteosarcoma progression are still unknown up to now. Here, we investigated the role of MALAT1 in human osteosarcoma cell lines and clinical tumor samples in order to determine the function of this molecule. In our research, the MALAT1 messenger RNA (mRNA) was highly expressed in human osteosarcoma tissues, and its expression level was closely correlated with pulmonary metastasis. Then, we employed lentivirus-mediated knockdown of MALAT1 in U-2 OS and SaO2 to determine the role of MALAT1 in osteosarcoma cell lines. Lentivirus-mediated MALAT1 small interfering RNA (siRNA) could efficiently downregulated the expression level of MALAT1 in osteosarcoma cell lines. Knockdown of MALAT1 inhibited the proliferation and invasion of human osteosarcoma cell and suppressed its metastasis in vitro and vivo. At the same time, the proliferating cell nuclear antigen (PCNA), matrix metallopeptidase 9 (MMP-9), phosphorylated PI3Kp85α, and Akt expressions were significantly inhibited in MALAT1-deleted cells. These findings indicated that MALAT1 might suppress the tumor growth and metastasis via PI3K/AKT signaling pathway. Taken together, our data indicated that MALAT1 might be an oncogenic lncRNA that promoted proliferation and metastasis of osteosarcoma and could be regarded as a therapeutic target in human osteosarcoma.

The HDF can be considered an effective and safe alternative procedure compared with ACDF in the treatment of the multilevel CSM, and ACCF should be the last option.

The purpose of this study was to compare modified plate-only laminoplasty and laminectomy and fusion to confirm which of the 2 surgical modalities could achieve a better decompression outcome and whether a significant difference was found in postoperative complications. Clinical data were retrospectively reviewed for 141 patients with cervical stenotic myelopathy who underwent plate-only laminoplasty and laminectomy and fusion between November 2007 and June 2010. The extent of decompression was assessed by measuring the cross-sectional area of the dural sac and the distance of spinal cord drift at the 3 most narrowed levels on T2-weighted magnetic resonance imaging. Clinical outcomes and complications were also recorded and compared. Significant enlargement of the dural sac area and spinal cord drift was achieved and well maintained in both groups, but the extent of decompression was greater in patients who underwent laminectomy and fusion; however, a greater decompression did not seem to produce a better clinical outcome. No significant difference was observed in Japanese Orthopaedic Association and Nurick scores between the 2 groups. Patients who underwent plate-only laminoplasty showed a better improvement in Neck Dysfunction Index and visual analog scale scores. In addition, limited decompression, rigid reconstruction of the spinal canal, and preservation of cervical mobility combined with preservation of the posterior structure resulted in a lower rate of postoperative C5 palsy and axial pain in the modified laminoplasty group. For this reason, modified laminoplasty may be a more viable option for patients with cervical stenotic myelopathy.