ABSTRACT
Objective To explore the expressions and correlation of RWD containing sumoylation enhancer (RSUME),small ubiquitin-like modifier (SUMO-1),hypoxia inducible factor-1α(HIF-1α)and vascular endothelial growth factor (VEGF)in gliomas of different pathologic grade.Methods We investigated the expression levels of RSUME mRNA,HIF-1α mRNA and VEGF mRNA with reverse transcription-polymerase chain reaction (RT-PCR),and investigated the immunohistochemical staining to determine the expressions of SUMO-1,HIF-1α and VEGF in 63 cases of human gliomas of different pathologic grade and 9 cases of normal brain tissues.We studied its correlation with the pathologic grade and the relationship between the expression of RSUME promoter sumoylation and HIF-1α/VEGF pathway in gliomas.Results There were significant differences (P <0.01)in the expressions of RSUME mRNA,HIF-1αmRNA and VEGF mRNA in glioma tissues.With the increasing degree of pathologic grade in tumor specimens,the expression levels of RSUME mRNA,HIF-1α mRNA and VEGF mRNA increased markedly (P <0.01 ).There was a positive correlation of the expression levels of RSUME mRNA with HIF-1αmRNA and VEGF mRNA.There were significant differences (P <0.01 )in the expressions of SUMO-1,HIF-1αand VEGF in glioma tissues by immunohistochemical staining.With the ascending of pathologic grade of tumor specimens,the expression levels of SUMO-1,HIF-1α and VEGF increased markedly (P < 0.01 ).There was a positive correlation between the expression level of SUMO-1 and HIF-1α(r =0.857,P <0.01).The Kaplan-Meier analysis and Log-rank test showed significant differences in progress free survival (PFS)between the RSUME high-expression and low-expression groups (χ2 =36.032,P <0.01).Conclusion RSUME may enhance HIF-1α/VEGF pathway through sumoylation in gliomas.It implicates that RSUME is related to angiogenesis in gliomas and can promote tumor invasion and progression,indicating that RSUME can be a novel target in gliomas treatment.