ObjectiveTo investigate regulation mechanism of glypican-3 (GPC3) on Hippo signaling pathway and its effects on biological behavior of hepatocellular carcinoma Huh7 cells. MethodsShort hairpin RNAs (shRNA) targeting GPC3 and Yes-associated protein 1 (YAP1) genes were constructed. All of the shRNAs were transfected into Huh7 cells by liposome transfection in order to screen out the stable expression cell lines. The expressions of GPC3 and YAP1 in Huh7 cells were detected by PCR and Western blot in order to screen out the effective shRNAs. The proliferation, invasion, and apoptosis of Huh7 cells were detected by Edu cell proliferation assay, transwell, and flow cytometry. GPC3 shRNA transfection experiments were divided into 6 groups:non-transfection group, empty vector group, GPC3-714-shRNA group, GPC3-647-shRNA group, GPC3-1718-shRNA group, and GPC3-2134-shRNA group. YAP1 shRNA transfection experiments were divided into 6 groups:non-transfection group, empty vector group, YAP1-906-shRNA group, YAP1-1363-shRNA group, YAP1-1666-shRNA group, and YAP1-2895-shRNA group. GPC3 regulation experiments were divided into 5 groups:non-transfection group, empty vector group, GPC3-1718-shRNA group, GPC3-1718-shRNA+ rhYAP1 group, and YAP1-1666-shRNA group. Results① GPC3-1718-shRNA and YAP1-1666-shRNA plasmids were successfully constructed to silence the expressions of GPC3 and YAP1. ② The expressions of GPC3 mRNA and protein in each transfection group were significantly lower than those in the non-transfection group (P<0.05) and the empty vector group (P<0.05), while which in the GPC3-1718-shRNA group was significantly lower than those in all the other transfection groups (P<0.05). The expressions of YAP1 mRNA and protein in each transfection group were significantly lower than those in the non-transfection group and empty vector group (P<0.05), while which in the YAP1-1666-shRNA group was significantly lower than those in all the other transfection groups (P<0.05). ③ The expressions of YAP1 mRNA and protein in the GPC3-1718-shRNA group and the YAP1-1666-shRNA group were significantly lower than those in the non-transfection group (P<0.05) and the empty vector group (P<0.05), while which in the GPC3-1718-shRNA+rhYAP1 group were significantly higher than those in the GPC3-1718-shRNA group (P<0.05) and the YAP1-1666-shRNA group (P<0.05). ④ Compared with the non-transfection group and the empty vector group, the abilities of cell proliferation and invasion in the GPC3-1718-shRNA group and the YAP1-1666-shRNA group were significantly decreased, and the cell apoptosis was significantly increased (P<0.05); The cell proliferation, invasion, and apoptosis in the GPC3-1718-shRNA+rhYAP1 group were significantly improved (P<0.05). ConclusionGPC3 is likely to affect biological behavior of hepatocellular carcinoma Huh7 cells through regulation of YAP1 in Hippo signaling pathway.
The classical Hippo pathway leads to the phosphorylation of downstream effector molecules Hippo-Yes-associated protein (Yap) and transcriptional coactivator PDZ-binding motif (Taz) serine sites through a kinase response, thereby promoting cell proliferation, controlling cell polarity, changing cytoskeleton, it plays an important regulatory role in various pathophysiological processes such as epithelial-mesenchymal transition and inhibition of cell contact. Studies have shown that Yap/Taz can affect the progression of vitreoretinal diseases, opening up new prospects for the pathogenesis and clinical treatment of diabetic retinopathy, proliferative vitreoretinopathy, and retinal ischemia-reperfusion injury. Exploring the molecular mechanism of Yap/Taz provides a possible therapeutic target for future research in the treatment of retinal fibrosis diseases such as diabetic retinopathy and proliferative vitreoretinopathy. At the same time, regulating the activity of local Yap/Taz in the retina will also become an effective therapeutic target for damage-repair in retinal ischemia-reperfusion injury. However, Yap inhibitors have potential retinal toxicity and are still in the preclinical development stage. Further research on the mechanism of action and clinical safety of Yap inhibitors will provide new methods for the treatment of retinal diseases.
Objective To investigate the expression of SAPCD2 in the lung adenocarcinoma cells, and to study the effect of SAPCD2 regulating Hippo signaling pathway on the proliferation, invasion, migration and apoptosis of the lung adenocarcinoma cells and its mechanism. Methods Quantitative real-time PCR (qRT-PCR) and Western blot were used to detect the expression levels of SAPCD2 mRNA and protein in four types of lung cancer cells (HCC827, H1650, SK-MES-1, A549) and human normal lung epithelial cells (BESA-2B), respectively. Then, lung cancer cells with relatively high levels of SAPCD2 expression were selected for subsequent experiments. The experiment cells were divided into a normal control group (NC group), a si-SAPCD2 group, and a pathway inhibitor group (si-SAPCD2+XMU-MP-1 group). Firstly, SAPCD2 mRNA was silenced using small interfering RNA (siRNA) technology, and then qRT-PCR was used to detect the expression of SAPCD2 in transfected lung cancer cells; using clone plate assay to detect the proliferation of lung cancer cells after silencing; using flow cytometry to detect the apoptosis of lung cancer cells after silencing; observe the number of lung cancer cells at different stages through cell cycle experiments; then Transwell experiment was used to analyze the effect of silencing SAPCD2 on the migration and invasion of lung cancer cell migration. Finally, Western blot was used to detect the expression of ki-67, Bcl-2, Caspase-3, NF2, P-MST1, P-LATS1, P-YAP, YAP, and TAZ proteins.Results SAPCD2 had the highest expression level in lung adenocarcinoma A549 cells (P<0.01). Silencing SAPCD2 significantly decreased the proliferation ability of A549 cells (P<0.01), inhibited their migration (P<0.05) and invasion (P<0.01), and promoted A549 cell apoptosis (P<0.01); more than half of the cells remained in the G0/G1 phase. Compared with the NC group, A549 cells showed a significant increase in G0/G1 phase cells (P<0.01), a significant decrease in G2/M and S phase cells (P<0.01), and a significant increase in the proportion of early apoptotic cells (P<0.01). Western blot results showed that silencing SAPCD2 down-regulated the expression of ki-67, Bcl-2, YAP, and TAZ proteins compared to the NC group (P<0.01), and up-regulated the expression of Caspase-3, NF2, P-MST1, P-LATS1, and P-YAP proteins (P<0.01). Conclusions The expression of SAPCD2 in lung adenocarcinoma A549 cells is significantly higher than that in normal lung epithelial cells (BESA-2B), which promotes the proliferation, migration and invasion of A549 cells and inhibits apoptosis. The mechanism may be related to the inhibition of Hippo signaling pathway.