Yippee Like 1 Suppresses Glioma Progression and Serves as a Novel Prognostic Factor.

Glioma is the most common tumor of central nervous system in adults with poor prognosis. Yippee Like 1 (YPEL1) is a newly discovered protein that plays contradictory roles in pancreatic cancer and colon cancer. Here we initially explored the expression, clinical significance, and function of YPEL1 in glioma. The transcription level of YPEL1 in glioma patients was extracted from TCGA datasets via GEPIA website. As a result, the mRNA level of YPEL1 was significantly lower in glioma tissues than that in normal brain tissues. Immunohistochemistry staining was next conducted to test protein expression of YPEL1 in glioma tissues (n = 130). Consistently, lower protein expression of YPEL1 was observed in cases with larger tumor size and advanced WHO grades. Univariate and multivariate analyses identified YPEL1 as a novel independent prognostic factor of gliomas. Finally, overexpression of YPEL1 was performed in U87 and U373 cell lines to further validate its tumor-related functions, followed by proliferation, invasion, and subcutaneous mice xenografts assays. In vitro and in vivo data demonstrated that overexpressing YPEL1 can remarkably prevent glioma cell proliferation and invasion. Taken together, our data revealed that low YPEL1 expression was significantly correlated with poor overall survival of glioma patients and may play anti-tumor effects.