Positive feedback loop of FAM83A/PI3K/AKT/c-Jun induces migration, invasion and metastasis in hepatocellular carcinoma.

FAM83A is part of an 8-member protein family of unknown function and is reported to be a cancer-promoting and treatment-resistance factor in several cancers. However, its role in hepatocellular carcinoma (HCC) remains unclear. Analysis of the Cancer Genome Atlas (TCGA) showed that FAM83A mRNA expression is upregulated in HCC, as are the protein expression levels in both HCC cell lines and tissues. Clinical data have demonstrated that high FAM83A expression is positively correlated with poor progression-free survival time, thus suggesting its cancer-promoting potential. Functional analyses showed that FAM83A overexpression promoted HCC cell migration and invasion in vitro and suppressed sorafenib sensitivity. Inhibiting FAM83A reversed these results. A pulmonary metastasis model further confirmed that FAM83A promoted HCC cell metastasis in vivo. Mechanistic analyses indicated that FAM83A activated the PI3K/AKT signaling pathway, its downstream c-JUN protein, and epithelial-to-mesenchymal transition (EMT)-related protein levels, including downregulation of E-cadherin and upregulation of Vimentin and N-cadherin. Interestingly, c-JUN induced FAM83A expression by directly binding to its promoter region and thus forming a positive-feedback loop for FAM83A/PI3K/AKT/c-JUN. In conclusion, we demonstrated that FAM83A, as a cancer-metastasis promoter, accelerates migration, invasion and metastasis by activating the PI3K/AKT/c-JUN pathway and inducing its self-expression via feedback, thus forming a FAM83A/PI3K/AKT/c-JUN positive-feedback loop to activate EMT signaling and finally promote HCC migration, invasion and metastasis.

Liu C ，Peng X ，Li Y ，Liu S ，Hou R ，Zhang Y ，Zuo S ，Liu Z ，Luo R ，Li L ，Fang W ... -  《-》

TRAF4 Regulates Migration, Invasion, and Epithelial-Mesenchymal Transition via PI3K/AKT Signaling in Hepatocellular Carcinoma.

Liu K ，Wu X ，Zang X ，Huang Z ，Lin Z ，Tan W ，Wu X ，Hu W ，Li B ，Zhang L ... -  《-》

Activation of phosphatidylinositol 3-kinase/Akt signaling mediates sorafenib-induced invasion and metastasis in hepatocellular carcinoma.

Wang H ，Xu L ，Zhu X ，Wang P ，Chi H ，Meng Z ... -  《-》

miR-300 regulates the epithelial-mesenchymal transition and invasion of hepatocellular carcinoma by targeting the FAK/PI3K/AKT signaling pathway.

Several microRNAs (miRNAs) have been closely correlated with the development of hepatocellular carcinoma (HCC). However, the involvement of miR-300 in the development of HCC remains unknown. This study elucidated the potential molecular mechanisms of miR-300 in the modulation of the epithelial-mesenchymal transition (EMT) and invasion of HCC. The expression levels of miR-300 in HCC cells and clinical samples were detected by quantitative real-time PCR and in situ hybridization. The in vitro function of miR-300 in HCC was evaluated using a migration/invasion assay. Quantitative real-time PCR, western blotting, immunofluorescence and immunohistochemistry were used to validate the roles of miR-300 and FAK/PI3K/AKT in EMT progression. A dual-luciferase reporter assay was performed to confirm the target gene. miR-300 was down-regulated in HCC and significantly correlated with a poor prognosis in HCC patients. The down-regulation of miR-300 increased the invasiveness of the HCC cells, and promoted the EMT in both HCC tissues and HCC cells. In contrast, up-regulation of miR-300 led to the opposite results. Ectopic overexpression of miR-300 reversed TGF-β1-induced EMT in SMMC-7721 cells, and according to a dual-luciferase reporter assay and rescue assay, miR-300 inhibits the EMT-mediated migration and invasion of HCC cells via the targeted modulation of FAK and the downstream PI3K/AKT signaling pathway. miR-300 targeting modulates FAK, and the PI3K/AKT signaling pathway inhibits the EMT and suppresses the migration and invasion of HCC cells. Thus, miR-300 represents a promising therapeutic target for HCC.

Wang R ，Yu Z ，Chen F ，Xu H ，Shen S ，Chen W ，Chen L ，Su Q ，Zhang L ，Bi J ，Zeng W ，Li W ，Huang X ，Wang Q ... -  《-》

Activation of phosphatidylinositol 3-kinase/AKT/snail signaling pathway contributes to epithelial-mesenchymal transition-induced multi-drug resistance to sorafenib in hepatocellular carcinoma cells.

Dong J ，Zhai B ，Sun W ，Hu F ，Cheng H ，Xu J ... -  《PLoS One》