Genetic alterations in meningiomas of different textures.

Meningiomas are complex brain tumors and 20% of meningiomas are clinically aggressive and recur. Aside from descriptors such as "soft" or "hard", the precise molecular mechanisms underlying these two subtypes have been unclear. In our study, we applied Affymetrix GeneChip Human Transcriptome Array 2.0 against 3 "soft" texture meningioma patients and 3 "hard" textures meningiomas as well as 3 normal controls. The array data showed that 949 coding genes and 568 non-coding RNAs in soft texture meningioma groups and 796 coding genes and 479 non-coding RNAs in hard textures were differentially expressed compared with control group. We further discovered 283 overlapped up-regulated genes and 279 overlapped down-regulated genes in soft and stiff groups. Osteomodulin and Alpha-2 Type I Collagen changed most in soft and hard texture meningiomas respectively. Gene ontology analysis against the differentially changed genes revealed that extracellular matrix assembly and disassembly dysfunction might lead to the differences between soft and hard textures. Meanwhile, pathway analysis demonstrated that extracellular matrix was the nature cause of the difference between the two subtypes. Our data firstly provide the molecular difference between soft and hard textures which are propitious to dissecting the pathological mechanism of meningiomas and targeted therapy.