Differential lncRNA expression profiles in recurrent gliomas compared with primary gliomas identified by microarray analysis.

Glioma, especially high-grade glioma, is highly malignant with high rate of recurrence and poor prognosis. The mechanisms of glioma progression and recurrence have not been elucidated. Previous studies showed that long non-coding RNAs (lncRNAs) involved in the development and progression of glioma. However, the roles of lncRNAs in the recurrence of glioma remain unknown. We use high throughput microarray to screen the differentially expressed lncRNAs and mRNAs in recurrence gliomas compared with primary gliomas. We found a total of 1,111 lncRNAs were differentially expressed in recurrent group. Among these, 639 lncRNAs were up-regulated, while 472 lncRNAs were down-regulated (fold Change ≥2.0). GO (Gene ontology) and pathway analysis revealed that the potential functions of differentially expressed lncRNAs were closely connected with the processes of cancer progression and pathogenesis. LncRNA classification and subgroup analysis further identified three important clusters of differentially expressed lncRNA-mRNA pairs which have potential gene regulatory functions. This study for the first time showed abundant differentially expressed lncRNAs in recurrent gliomas. Some lncRNAs may play important roles in glioma recurrence, such as previously reported H19, CRNDE, HOTAIRM1 or unreported AC016745.3, XLOC_001711, RP11-128A17.1. Moreover, this study set a basis for future researches on specific lncRNA which may contribute to the recurrence of glioma. Further studies on these lncRNAs will help to elucidate the mechanism of glioma recurrence at genetic level and find therapeutic targets for glioma patients.