Genetic Alterations Between Normal Arachnoid Brain Tissue And Meningiomas And Meningiomas Of Different Grades

Objective: Meningiomas are the most common primary brain tumors.Most of them are benign and curable by operation,the texture and pathological grades of meningiomas are important prognostic factors.With the reclassifications of tumors of central nervous system,the incidence of atypical meningiomas has increased from 3%-5% to 20%-35%.However,the molecular mechanisms of underlying the textures,development and progression of meningiomas are still poorly understood.In this study,we analyzed the differential gene expression profile between normal brain arachnoid tissue and meningiomas of different textures and grades.Furthermore,we did pathway analysis about these differential genes,uncovering the molecular basis of textures,development and progression of meningiomas.Method: We detected gene expression profile with normal brain arachnoid tissue and meningiomas of different textures and grades via applying Affymetrix Genechip Human Transcriptome Array 2.0.The up-regulated or down regulated genes(>2 folds)between normal brain arachnoid tissue and benign meningiomas,normal brain arachnoid tissue and atypical meningomas were extracted from the results.Furthermore,GO analysis and pathway analysis were applied to these differentially expressed genes.Results: Compared to the normal brain arachnoid tissue,there were 949 differentially expressed genes in the soft meningiomas group and 796 differentially expressed genes in the hard meningiomas group.Besides that,there were 512 overlapped genes between the soft meningiomas and hard meningiomas.The results showed no opposite trend between soft and hard meningiomas among differentially expressed genes.However,change folds were different in meningiomas of different textures.Pathway analysis showed extracellular matrix played a key role in the different textures.Compared to the normal brain arachnoid tissue,there were 2256 differentially expressed genes in the benign meningiomas group and 2774 differentially expressed genes atypical meningiomas group.There were 2051 over-lapped genes between benign and atypical meningiomas.Pathway analysis against differentially expressed genes revealed extracellular matrix assembly and disassembly might lead to the differences between normal brain arachnoid tissue and meningiomas.Mutation of EPH and POSTN,pathways related integrin were the main cause resulting to the differences between benign and atypical meningiomas.Conclusions: In this study,we established differentially expressed gene profile of normal brain arachnoid tissue and meningiomas of different textures and grades via applying genechip.Pathway analysis showed extracellular matrix played a key role in the different textures of meningioms.Mutation of EPH and POSTN,pathways related integrin were the main cause resulting to the differences between benign and atypical meningiomas.These results provide new data for different grades,progression and targeted therapy of meningiomas.