| Objectives: To determine the expression level of immunoproteasome in glioma tissues and its relationship with the clinical characteristics and prognosis of glioma patients preliminarily.Furthermore,we studied the function and molecular mechanism of proteasome inhibitor ONX0912 on glioma cells.Methods: The expression of immunoproteasome in glioma and normal control brain tissue samples was detected by Western blot.55 cases of glioma tissues and 6 cases of normal control brain tissues were collected and the tissue microarray slice was produced routinely.Immunohistochemical technique was used to detect the expression of LMP7 in tissue samples.Chi square was used to analyze the relationship between the expression level of LMP7 and clinical characteristics.Cox regression analysis and Kaplan-Meier method was applied to analyze the correlation between the expression level of LMP7 with prognosis of patients.MTS proliferation assay and flow cytometry were introduced to detect the impact of ONX0912 on the proliferation of glioma cells.Western blot was used to detect the apoptosis and autophagy related protein expression in U87,U251 and A172 glioma cell lines treated with ONX0912.Results: The expression level of LMP7 in glioma tissues was significantly higher than that of the normal control brain tissues,and the difference was significant(p<0.01).The expression level of LMP7 in high grade glioma was significantly higher than that of low grade glioma,and the difference was significant(p<0.01).The prognosis analysis showed that the mean survival time of patients with high expression of LMP7 was 37.5 ±2.7 months,while that of patients with low expression of LMP7 was 51.0 ±2.2 months,and the difference was significant(p<0.05).The analysis of prognostic factors showed that the expression of LMP7 could be used as an independent prognostic factor in glioma patients,and the difference was significant(p<0.05).The results of MTS assay and flow cytometry showed that ONX0912 could inhibit the proliferation of glioma cells in different degrees.Western blot detects the expression of apoptosis-related proteins and revealed that ONX0912 could increase the expression of pro-apoptotic protein Bax and decrease the expression of anti-apoptotic protein Mcl-1 in glioma cells,besides,apoptosis-related proteins such as caspase-3 and cPARP also increased.Western blot detects the expression of autophagy related proteins and revealed that ONX0912 could increase the expression of p62 and LC3.Conclusions: 1.The expression of immunoproteasome LMP7 was up-regulated in glioma tissues,and its expression increased with the increase of pathological grade,which was negatively correlated with the prognosis of glioma patients and could be used as an independent prognostic factor.2.Proteasome inhibitor ONX0912 can inhibit the proliferation of glioma cells by promoting glioma cell apoptosis and autophagy. |
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