This study is aimed to clarify the potential role of lncRNA LINC00899 in invasion and migration of spinal ependymoma cells through the FoxO pathway via RBL2. Spinal ependymoma related chip data (GSE50161 and GSE66354) was initially downloaded and differentially expressed lncRNAs were screened out. Fifty-eight cases of spinal ependymoma and normal ependymal tissues were collected. The effects of LINC00899 and RBL2 on the spinal ependymoma cell migration and invasion were determined using the third generation spinal ependymoma cells and transfection with LINC00899 vector, siRNA-LINC00899 and siRNA-RBL2. The expression of LINC00899, pathway and cell proliferation-and apoptosis-related factors was determined. Finally, we also detected cell proliferation, migration, invasion, cycle and apoptosis after transfection. Our results showed that LINC00899 was up-regulated in spinal ependymoma and RBL2 was confirmed as a target gene of LINC00899 and found to be involved in regulation of FoxO pathway. LINC00899 expression increased in spinal ependymoma tissues whereas RBL2 expression decreased. Moreover, we found that siRNA-LINC00899 could elevate RBL2, p21, p27 and Bax levels, decrease FoxO, Bcl-2, Vimentin, Annexin levels, reduced cell proliferation, migration and invasion and enhanced apoptosis. Taken together, our study suggests that down-regulated LINC00899 exerts anti-oncogenic effects on spinal ependymoma via RBL2-dependent FoxO, which provides a novel therapeutic target for the treatment of spinal ependymomas.

Introduction: Colorectal neoplasia differentially expressed (CRNDE) was reported to promote carcinogenesis in several cancers. However, the role of CRNDE in glioblastoma multiforme (GBM) needs to be further explored. Methods: CRNDE expression levels in GBM tissues and cells were explored using realtime quantitative PCR at first. Effects of CRNDE on GBM cell behaviors were detected by conducting in vitro experiments. Interactions of CRNDE, microRNA-337-3p (miR-337-3p), and ELMO domain containing 2 (ELMOD2) were verified by bioinformatics analysis tools and dual-luciferase reporter assay. Expression correlations of CRNDE and ELMOD2 in GBM tissues were analyzed at GEPIA website. Results: CRNDE expression was upregulated in GBM tissues and cells compared with normal counterparts. CRDNE knockdown inhibits proliferation and migration, but promotes apoptosis in GBM cell, while CRNDE overexpression caused opposite effects. Mechanisms exploration indicated CRNDE serves as sponge of miR-337-3p to upregulate ELMOD2 expression. Furthermore, we showed CRNDE and ELMOD2 were positively correlated in GBM tissues. Discussion: In conclusion, our study highlighted the importance of CRNDE/miR-337-3p/ ELMOD2 axis in GBM progression and offered novel strategies for GBM treatment.