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
