Background
Hepatitis B virus X protein (HBx) plays a crucial role in initiating and promoting HBV‐induced hepatocellular carcinoma (HCC) development. Reports indicated that HBx promotes cancer stem cell (CSC) generation, which may be associated with HBV‐related HCC. Noncoding RNA miR‐124 and long noncoding RNA (lncRNA)‐metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1) were considered to be involved deeply in the progress of HBx‐related HCC. Hence, the underlying mechanism of miR‐124 and lncRNA‐MALAT1 in regulating HBx‐promoted CSC needs to be studied.
Materials and Methods
In present study, HepG2‐X cell line was induced by transfect HBx into HepG2 cells. Overexpressing of miR‐124 or silencing of lncRNA‐MALAT1 was completed by transfecting miR‐124 mimic or shMALAT1 into HepG2‐X cells. HBx‐induced CSC properties and tumorigenic potential of HepG2 cells were determined by detecting CSC marker expression, colony formation assay, and xenograft tumorigenesis. The mechanism of HBx‐induced CSC properties was explored by PI3K/Akt inhibitor. Interaction of miR‐124 and lncRNA‐MALAT1 was detected by luciferase reporter assay.
Results
HBx promoted CSC properties through upregulating stemness markers and reprogramming proteins, and contributed to tumorigenicity of HepG2‐X cells both in vivo and in vitro. Inhibition of Akt activation blocked the HBx‐stimulated reprogramming proteins and stemness markers. HBx upregulated lncRNA‐MALAT1 expression while downregulating miR‐124 expression in HepG2‐X cells. miR‐124 interacts with lncRNA‐MALAT1 by direct targeting. Overexpression of miR‐124 or silencing of lncRNA‐MALAT1 both blocked HBx‐induced CSC generation, stemness‐related factor activation and tumorigenicity via PI3K/Akt signaling.
Conclusion
Our results demonstrated that miR‐124 interact with lncRNA‐MALAT1 and involve in regulating HBx‐induced CSC properties via PI3K/Akt signaling.