LncRNA H19 is overexpressed in glioma tissue, is negatively associated with patient survival, and promotes tumor growth through its derivative miR-675.

OBJECTIVE: Glioma is one of the most common and invasive tumors of the central nervous system. Long non-coding (lnc) RNAs are involved in many cancers, but their function and mechanism in glioma remain largely unknown. We wished to delineate the role of lncRNA H19 and its derivative miR-675 in this tumor.

PATIENTS AND METHODS: Using qPCR, we compared expression of lncRNA H19 in 35 specimens of glioma vs control tissue, and in two glioma cell lines U251 and U87 vs Normal Human Astrocyte (NHA) cells. Cell proliferation was evaluated after shRNA silencing of lncRNA H19 in glioma cell lines. The role of miR-675 was tested using antagomir and the mimic.

RESULTS: LncRNA H19 was overexpressed in glioma tissue and cell lines. In tissue, higher expression levels were observed in more advanced stages of the tumor. Furthermore, lncRNA H19 was negatively associated with patient survival time. In cell culture experiments, silencing of lncRNA H19 diminished proliferation of glioma cell lines. These effects of lncRNA H19 appeared to be intermediated by miR-675. The latter was overexpressed in glioma tissue and was negatively associated with patient survival. Supporting the involvement of miR-675, its antagomir decreased proliferation of glioma cell lines, whereas its mimic increased proliferation of NHA cells.

CONCLUSIONS: LncRNA H19 is overexpressed in glioma tissue, and is positively associated with the tumor grade and negatively associated with patient survival. In cell culture studies, lncRNA H19 promotes glioma cell proliferation. These tumor-promoting effects of lncRNA H19 appear to be mediated by miR-675.