Silencing of lncRNA PVT1 by miR-214 inhibits the oncogenic GDF15 signaling and suppresses hepatocarcinogenesis.

ABSTRACT

The prognosis for hepatocellular carcinoma (HCC) is dismal. Long noncoding RNA PVT1 has been linked to malignancies and might be a deleterious therapy target. However, the key events controlling its expression in HCC remain undetermined. Here, we address how PVT1 is fine-regulated and its downstream signaling in hepatoma cells. Interestingly, we found that c-Myc and P53 could divergently regulate PVT1 transcription. Oncoprotein c-Myc enhances PVT1 expression, whereas P53 suppresses its expression. We also identified miR-214 as a crucial, negative regulator of PVT1. Consistently, high miR-214 levels were significantly correlated with diminished PVT1 expression in HCC specimens. Silencing of PVT1 by ectopic miR-214 or siRNAs markedly inhibited viability and invasion of HCC cells. In opposition, inhibition of endogenous miR-214 promoted PVT1 expression and enhanced cell proliferation. Notably, oncogenic GDF15 is a potential downstream target of the miR-214-PVT1 signaling. Collectively, our results show that the c-Myc/P53/miR-214-PVT1-GDF15 axis is implicated in HCC development, shedding light on the mechanistic actions of PVT1 and representing potential targets for HCC clinical intervention.