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The deregulation of HGF/c-Met signaling is implicated in epithelial-mesenchymal transition (EMT) and progress of hepatocellular carcinoma (HCC). However, the epigenetic mechanisms that HGF/c-Met regulates EMT and metastasis of HCC cells are less explored. In this study, we demonstrated that HCC cells express a high level of SUMO/sentrin-specific protease 1 (Senp1) which is induced by HGF/c-Met signals. Lentivirus-mediated small hairpin RNA (shRNA) transduction results in Senp1 silence in HCC cells. Senp1 silence reduces the HGF-induced proliferation and migration of HCC cells. Senp1 inhibition also induces HCC cell apoptosis and growth arrest. Furthermore, Senp1 knockdown inhibits epithelial-to-mesenchymal transition, with increase of E-cadherin and ZO-1 expression, decrease of fibronectin and N-cadherin expression. The EMT-related transcription factor Zeb1 was SUMO-modified and decreased in Senp1-silenced HCC cells. These results delineate that senp1 might play an important role in the regulation of HGF-induced invasion and migration of HCC cells. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of HIF-2α silencing by transfection of siRNA into MG-63 cells under hypoxia. Methods HIF-2α expression level in MG-63 cells under hypoxia was determined by Western Blot. Small interfering RNA (siRNA) was used to construct MG-63/siHIF-2a (siHIF-2α) cells and control MG-63/scramble (NC) cells. The expression levels of HIF-2α, Vascular endothelial growth factor (VEGF), p-Erk/ErK and Mcl-1 in MG-63, NC and siHIF-2α cells was determined by Western Blot. NC and siHIF-2α cells were cultured under hypoxia. Cell viability was assessed by MTT assay. Migration was identified by scratch migration assay. Tumor formation was identified by clone formation assay. Nude mouse subcutaneous xenograft model was used to investigate tumor development in vivo. Results Hypoxia improved HIF-2α expression in MG-63 cells in a time-dependent manner (F=2 037.412, P<0.001). HIF-2α expression under hypoxia in siHIF-2acells was lower than that in NC cells (P<0.01). Cell viability of siHIF-2α cells under hypoxia for 12 h and 24 h were lower than that in NC cells (P<0.05 or P<0.01). The relative width of scratch in siHIF-2α group under hypoxia for 12 h and 24 h were larger than that in NC group (P<0.01 or P<0.01). When cell counts reach 1 000-5 000, the clone formation rates of siHIF-2α cells were lower than that in NC cells (P<0.05 or P<0.01). The expression of VEGF, p-Erk/Erk and Mcl-1 protein under hypoxia in siHIF-2α cells was lower than that in NC cells(P<0.01). Tumor sizes, weights and density of siHIF-2α group in nude mice were suppressed compared with those in NC group (P<0.01). Conclusion Blocking HIF-2α signal pathway warrants its investigation as a potential strategy in osteosarcoma treatment. [ABSTRACT FROM AUTHOR]

The deregulation of HGF/c-Met signaling is implicated in epithelial-mesenchymal transition (EMT) and progress of hepatocellular carcinoma (HCC). However, the epigenetic mechanisms that HGF/c-Met regulates EMT and metastasis of HCC cells are less explored. In this study, we demonstrated that HCC cells express a high level of SUMO/sentrin-specific protease 1 (Senp1) which is induced by HGF/c-Met signals. Lentivirus-mediated small hairpin RNA (shRNA) transduction results in Senp1 silence in HCC cells. Senp1 silence reduces the HGF-induced proliferation and migration of HCC cells. Senp1 inhibition also induces HCC cell apoptosis and growth arrest. Furthermore, Senp1 knockdown inhibits epithelial-to-mesenchymal transition, with increase of E-cadherin and ZO-1 expression, decrease of fibronectin and N-cadherin expression. The EMT-related transcription factor Zeb1 was SUMO-modified and decreased in Senp1-silenced HCC cells. These results delineate that senp1 might play an important role in the regulation of HGF-induced invasion and migration of HCC cells.

The stable isotope labeling by amino acids in culture (SILAC) based quantitative proteomics serves as a gold standard because of the high accuracy and throughput for protein identifications and quantification. In this study, we discussed the application of SILAC technology in mammal model, and developed quantitative internal standard for comparative proteomics of disease model. The C57BL/6J mice fed by special diet containing the 13C6-Lysine and bred F2 generation. We identified and analyzed total proteins of 9 mice tissues of F2 generation, including brain, lung, heart, stomach, intestine, liver, spleen, kidney, and muscle. Quantitative analysis information could evaluate the mice and different tissues' labeling efficiency. Liver was the most efficient, brain the least, and the labeling efficiency were 96.34%±0.90% and 92.62%±1.98% respectively. The average of the labeling efficiency of F2 generation was 95.80%±0.64%, which met the international standard (≥ 95%) for SILAC quantitative proteomics effective study. SILAC technology was successfully extended to mammalian model system, which will provide powerful tools for the mechanism study of the pathophysiology process with mouse model.