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Invadopodium formation is a crucial early event of invasion and metastasis of hepatocellular carcinoma (HCC). However, the molecular mechanisms underlying regulation of invadopodia remain elusive. This study aimed to investigate the potential role of discs large homolog 5 (Dlg5) in invadopodium formation and function in HCC. We found that Dlg5 expression was significantly lower in human HCC tissues and cell lines than adjacent nontumor tissues and liver cells. Lower Dlg5 expression was associated with advanced stages of HCC, and poor overall and disease-free survival of HCC patients. Dlg5-silencing promoted epithelial-mesenchymal transition, invadopodium formation, gelatin degradation function, and invadopodium-associated invasion of HepG2 cells. In contrast, Dlg5 overexpression inhibited epithelial-mesenchymal transition, functional invadopodium formation, and invasion of SK-Hep1 cells. Both Girdin and Tks5, but not the Tks5 nonphosphorylatable mutant, were responsible for the enhanced invadopodium formation and invasion of Dlg5-silenced HepG2 cells. Furthermore, Dlg5 interacted with Girdin and interfered with the interaction of Girdin and Tks5. Dlg5 silencing promoted Girdin and Tks5 phosphorylation, which was abrogated by Girdin silencing and rescued by inducing shRNA-resistant Girdin expression. Moreover, Dlg5 overexpression significantly inhibited HCC intrahepatic and lung metastasis in vivo. Taken together, our data indicate that Dlg5 acts as a novel regulator of invadopodium-associated invasion via Girdin and by interfering with the interaction between Girdin and Tks5, which might be important for Tks5 phosphorylation in HCC cells. Conceivably, Dlg5 may act as a new biomarker for prognosis of HCC patients.

Downregulation of cell division cycle-associated 3 (CDCA3) markedly inhibited cell growth and induced apoptosis in tumors. However, the effect of CDCA3 in pancreatic cancer (PAC) was rarely investigated. Therefore, this study attempted to clarify the role of CDCA3 in PAC. The mRNA and protein expression of CDCA3 were examined in PAC cell lines and tumor tissues by using real-time quantitative PCR (RT-qPCR), western blotting (WB), and immunohistochemistry (IHC). The effects of CDCA3 downregulation on cell proliferation, apoptosis, and colony information were investigated through MTT assay, Annexin V-APC single staining cell apoptosis detection, and colony formation test. The microarray and ingenuity pathway ana lysis were employed to explore the potential regulato ry relation. The tumor xenograft model was established for determining the effect of CDCA3 downregulation on the growth of PAC in vivo. The results showed that the expression of CDCA3 in tumor tissues wa s higher than that of normal tissues (P < 0.05). In addition, the mRNA expression of CDCA3 was markedly increased in PANC-1 cells and SW 1990 cells when compared with human pancreatic duct epithelial (HPDE) cells (P < 0.05). MTT assay showed that the cell proliferation of PANC-1 cells and SW1990 cells was significantly inhibited after the lentivirus transfection of CDCA3 knockdown (P < 0.05). Annexin V-APC apoptosis assays suggested that the apoptotic cell number was markedly increased in the shCDCA3 group compared to that in the shCtrl group in SW1990 cells and PANC-1 cells (P < 0.05). Meanwhile, the activity of caspase-3/7 was obviously elevated in the shCDCA3 group compared to the shCtrl group (P < 0.05). The colony formation was notably inhibited in the shCDCA3 group relatively to the shCtrl group in SW1990 cells (P < 0.05). Moreover, the tumor growth was evidently suppressed in shCDCA3 group compared with shCtrl group in vivo (P < 0.05). These findings revealed that CDCA3 plays a crucial role in the progress of PCA by regulating cell apoptosis and proliferation, which may serve as a potential target for PAC treatment.

It was previously demonstrated that the long non-coding RNA (lncRNA) small NF90-associated RNA (snaR) served an oncogenic role in human colon cancer, although its roles in other types of cancer remain unknown. To investigate the potential involvement of lncRNA snaR in hepatocellular carcinoma (HCC), expression of snaR in liver biopsies and plasma of patients with HCC and healthy controls was detected by reverse transcription-quantitative polymerase chain reaction. ELISA was used to determine the protein expression levels of transforming growth factor-β1 (TGF-β1). A snaR expression vector was transfected into HCC cells, and the effects on cell migration and invasion were analyzed by Transwell migration and Matrigel invasion assays, respectively. The protein expression levels of TGF-β1 in HCC cells were detected by western blotting. The expression of snaR and TGF-β1 was significantly increased in the patients with HCC compared with the healthy controls. The plasma expression levels of snaR and TGF-β1 were positively correlated in patients with HCC; however, not in healthy controls. snaR overexpression significantly promoted cancer cell migration and invasion, and additionally increased TGF-β1 expression. Treatment with TGF-β1 did not significantly affect snaR expression. A TGF-β1 inhibitor attenuated the effects of snaR overexpression in cancer cell migration and invasion. snaR may promote the metastasis of liver cancer through TGF-β1.

BackgroundHepatocellular carcinoma (HCC) is the most common primary liver cancer in the world, with a high degree of malignancy and recurrence. The influence of the ceRNA network in tumor on the biological function of liver cancer is very important, It has been reported that many lncRNA play a key role in liver cancer development. In our study, integrated data analysis revealed potential eight novel lncRNA biomarkers in hepatocellular carcinoma.MethodsTranscriptome data and clinical data were downloaded from the The Cancer Genome Atlas (TCGA) data portal. Weighted gene co-expression network analysis was performed to identify the expression pattern of genes in liver cancer. Then, the ceRNA network was constructed using transcriptome data.ResultsThe integrated analysis of miRNA and RNAseq in the database show eight novel lncRNAs that may be involved in important biological pathways, including TNM and disease development in liver cancer. We performed function enrichment analysis of mRNAs affected by these lncRNAs.ConclusionsBy identifying the ceRNA network and the lncRNAs that affect liver cancer, we showed that eight novel lncRNAs play an important role in the development and progress of liver cancer.