Background. It has been reported that the expression of SPP1, the mRNA for osteopontin （OPN）, is increased in anumber of transformed cell lines and some tumors. Increased serum and plasma OPN levels were associated with advanced-stage carcinomas of the lung, breast, colon and prostate. The extent of OPN expression may be correlated with the malignancy degree of gliomas, but the specific role of OPN in the malignancy of gliomas remains to be cla.rified, Methods： In this study, we used a lentiviral system, which could induce a long-lasting down-regulation of gene exprossion, to knock down the OPN gene in human glioma cell line U251. And then we observed the proliferation and apoptosis of glioma cells. Results： OPN mRNA and protein were successfully knocked down in U251 cells, and the expression of caspase-3 and caspase-9 were increased about by 2 folds in OPN down-regulated U251 cells. 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium （MTT） assay showed that OPN down-regulation did not affect the proliferation of U251 cells. Conclusion： Our findings indicate that OPN might play a role in apoptosis, but not in cell proliferation in U251 glioma cells.
Xu TaoChen JuxiangLu YichengZhou JinxuYan YongHu GuohanLuo ChunHuang Yan
以病例为基础的学习(Case Based Learning,CBL)模式是基于以问题为基础的学习(Problem-Based Learning,PBL)发展而来的全新教学模式,教学形式多样,其核心是以"临床病例为先导,以问题为基础"的小组讨论式教学法,适应临床医学教学的要求,正逐渐成为临床教学中的重要方法。本文结合自身实践经验,探讨CBL教学模式在神经外科临床教学中的优势、意义、难点及局限性,以期对后续临床教学提供经验借鉴。
