Micro RNA-1290 promotes esophageal squamous cell carcinoma cell proliferation and metastasis

AIM:To investigate the biological role of mi R-1290 in esophageal squamous cell carcinoma(ESCC) progression and invasion and the underlying mechanism.METHODS:Quantitative real-time polymerase chain reaction(q RT-PCR) was performed to evaluate mi R-1290 expression in ESCC tissue samples.The roles of mi R-1290 in cell proliferation,migration and invasion were identified using mi R-1290 mimic-transfected cells.In addition,the regulatory effect of mi R-1290 on suppressor of cancer cell invasion(SCAI) was evaluated using q RT-PCR,Western blot analysis and a dual luciferase reporter assay.RESULTS:mi R-1290 was significantly upregulated in ESCC tissue samples compared with normal adjacent tissues(9.213 ± 1.150 vs 1.000 ± 0.0),(P 0.01).Upregulation of mi R-1290 was associated with tumor differentiation(P = 0.021),N classification(P = 0.006) and tumor-node-metastasis stage(P = 0.021) in ESCC patients.Moreover,ectopic mi R-1290 expression potently promoted ESCC cell growth(P 0.01),migration(P 0.01) and invasion(P 0.01) in vitro.mi R-1290 overexpression in ESCC cell lines decreased SCAI expression at the translational level and reduced SCAI-driven luciferase-reporter activity(P 0.01).CONCLUSION:Our findings suggested that mi R-1290 may play an oncogenic role in cellular processes of ESCC.     

SULF1 Inhibits Proliferation and Invasion of Esophageal Squamous Cell Carcinoma Cells by Decreasing Heparin-Binding Growth Factor Signaling

Background

Heparin-binding growth factor signaling is involved in the pathogenesis and development of human cancers. It can be regulated by sulfation of cell-surface heparan sulfate proteoglycans (HSPG). SULF1 is a heparin-degrading endosulfatase which can modulate the sulfation of HSPGs.

Aim

The purpose of this study was to elucidate the role of SULF1 in modulating proliferation and invasion of esophageal squamous cell carcinoma (ESCC) by decreasing heparin-binding growth factor signaling.

Methods

We restored SULF1 expression in the ESCC cell line KYSE150, and examined the effects of SULF1 expression on the proliferation and invasion of KYSE150 cells. In addition, we investigated the expression of SULF1 in human ESCC tissues and analyzed the correlation of SULF1 expression with clinicopathologic characteristics of ESCC.

Results

Our study shows that re-expression of SULF1 in ESCC cell line results in the downregulation of hepatocyte growth factor-mediated activation of MAPK pathways with a resultant decrease in cell invasiveness. Cell proliferation was also inhibited in SULF1-transfected KYSE150 cells. Immunohistochemical assays reveal that SULF1 is expressed in nearly half of the human ESCC tissues but not in normal esophageal epithelial cells. SULF1 expression in human ESCC tissues is negatively correlated with tumor size and tumor invasion.

Conclusion

This study identified that SULF1 inhibits proliferation and invasion of ESCC by decreasing heparin-binding growth factor signaling and suggested that SULF1 plays an inhibiting role in the pathogenesis of ESCC.     

Cortactin expression confers a more malignant phenotype to gastric cancer SGC-7901 cells

AIM:To study the effects of cortactin on the tumor biology of SGC-7901 cells and identify the mechanism involved in the process.METHODS:Cell lines in which cortactin was stably overexpressed or knocked down as well as the respective control cell lines were established by standard molecular methods.The effects of cortactin on the proliferation,migration and invasion capacity of SGC-7901cells were assessed by the MTT assay,colony formation,flow cytometry,transwell migration and matrigel invasion.Nude mouse models were also used to assess the role of cortactin in the growth and metastasis of SGC-7901 cells in vivo.Western blotting analysis was performed to detect the expression of epidermal growth factor receptor(EGFR)and downstream molecules.RESULTS:Cell lines in which cortactin was stably overexpressed or knocked down as well as control cell lines were successfully established and designated as LV5-cortactin-SGC,LV5-SGC,LV3-shRNA-SGC and LV3-SGC.Cortactin overexpression promoted SGC-7901 cell migration(340.7±12.6 vs 229.1±23.2,P<0.01)and invasion(71.6±5.2 vs 48.4±3.6,P<0.01).Cortactin downregulation impaired SGC-7901 cell migration(136.2±19.8 vs 225±17)and invasion(29.2±5.2vs 49.6±3.8,P<0.01).The results from the MTT and colony formation assays results indicated increased LV5-cortactin-SGC cell proliferation and decreased LV3-shRNA-SGC cell proliferation compared to the control cells.Flow cytometry analysis demonstrated that cortactin overexpression promoted the proliferation index of SGC-7901 cells,and the results were reversed when cortactin was downregulated.Mouse tumor models confirmed that cortactin expression increased SGC-7901cell proliferation and metastasis in vivo.Western blotting analysis revealed that cortactin elevated EGFR expression and activated the downstream molecules.CONCLUSION:Cortactin expression promoted the migration,invasion and proliferation of SGC-7901 cells both in vivo and in vitro.The EGFR signaling pathway is mechanistically involved.     

Suppression of colorectal cancer metastasis by nigericin through inhibition of epithelial-mesenchymal transition

AIM: To evaluate the effect of nigericin on colorectal cancer and to explore its possible mechanism.METHODS: The human colorectal cancer (CRC) cell lines HT29 and SW480 were treated with nigericin or oxaliplatin under the conditions specified. Cell viability assay and invasion and metastasis assay were performed to evaluate the effect of nigericin on CRC cells. Sphere-forming assay and soft agar colony-forming assay were implemented to assess the action of nigericin on the cancer stem cell properties of CRC cells undergone epithelial-mesenchymal transition (EMT).RESULTS: Compared with oxaliplatin, nigericin showed more toxicity for the HT29 cell line (IC50, 12.92 ± 0.25 μmol vs 37.68 ± 0.34 μmol). A similar result was also obtained with the SW116 cell line (IC50, 15.86 ± 0.18 μmol vs 41.02 ± 0.23 μmol). A Boyden chamber assay indicated that a significant decrease in the number of HT29 cells migrating through polyvinylidene fluoride membrane was observed in the nigericin-treated group, relative to the vehicle-treated group [11 ± 2 cells per high-power field (HPF) vs 19.33 ± 1.52 cells per HPF, P < 0.05]. Compared to the control group, the numbers of HT29 cells invading through the Matrigel-coated membrane also decreased in the nigericin-treated group (6.66 ± 1.52 cells per HPF vs 14.66 ± 1.52 cells per HPF, P < 0.05). Nigericin also reduced the proportion of CD133⁺ cells from 83.57% to 63.93%, relative to the control group (P < 0.05). Nigericin decreased the number of spheres relative to the control group (0.14 ± 0.01 vs 0.35 ± 0.01, P < 0.05), while oxaliplatin increased the number of spheres relative to the control group (0.75 ± 0.02 vs 0.35 ± 0.01; P < 0.05). Nigericin also showed a decreased ability to form colonies under anchorage-independent conditions in a standard soft agar assay after 14 d in culture, relative to the control group (1.66 ± 0.57 vs 7 ± 1.15, P < 0.05), whereas the colony numbers were higher in the oxaliplatin group relative to the vehicle-treated controls (14.33 ± 0.57 vs 7 ± 1.15, P < 0.05). We further detected the expression of E-cadherin and vimentin in cells treated with nigericin and oxaliplatin. The results showed that HT29 cells treated with nigericin induced an increase in E-cadherin expression and a decrease in the vimentin expression relative to vehicle controls. In contrast, oxaliplatin downregulated the expression of E-cadherin and upregulated the expression of vimentin in HT29 cells relative to vehicle controls.CONCLUSION: This study demonstrated that nigericin could partly reverse the EMT process during cell invasion and metastasis.     

Tumor suppressor function of ezrin-radixin-moesin-binding phosphoprotein-50 through β-catenin/E-cadher in pathway in human hepatocellular cancer

AIM:To determine the effect and molecular mechanism of ezrin-radixin-moesin-binding phosphoprotein-50(EBP50) in hepatocellular carcinoma(HCC).METHODS:Three human HCC cell lines,i.e.,SMMC7721,HepG2 and Hep3B,were used.We transfected the Pbk-CMV-HA-EBP50 plasmid into SMMC7721 cells with Lipofectamine 2000 to overexpress EBP50.Western blotting were performed to determine the effects of the plasmid on EBP50 expression and to detect the expression of β-catenin and E-cadherin before and after the transfection of the plasmid into SMMC7721 cells.In vitro cell proliferation was assessed with a Cell Counting Kit-8(CCK-8) assay.Cell cycle distribution was assessed with flow cytometry.Invasion and migration ability of before and after the transfection were determined with a transwell assay.Cell apoptosis was demonstrated with Annexin V-FITC.The effect of EBP50 overexpressing on tumor growth in vivo was performed with a xenograft tumor model in nude mice.RESULTS:The transfection efficiency was confirmed with Western blotting(1.36 ± 0.07 vs 0.81 ± 0.09,P < 0.01).The CCK8 assay demonstrated that the growth of cells overexpressing EBP50 was significantly lower than control cells(P < 0.01).Cell cycle distribution showed there was a G0/G1 cell cycle arrest in cells overexpressing EBP50(61.3% ± 3.1% vs 54.0% ± 2.4%,P < 0.05).The transwell assay showed that cell invasion and migration were significantly inhibited in cells overexpressing EBP50 compared with control cells(5.8 ± 0.8 vs 21.6 ± 1.3,P < 0.01).Annexin V-FITC revealed that apoptosis was significantly increased in cells overexpressing EBP50 compared with control cells(14.8% ± 2.7% vs 3.4% ± 1.3%,P < 0.05).The expression of β-catenin was downregulated and E-cadherin was upregulated in cells overexpressing EBP50 compared with control cells(0.28 ± 0.07 vs 0.56 ± 0.12,P < 0.05;0.55 ± 0.08 vs 0.39 ± 0.07,P < 0.05).In vivo tumor growth assay confirmed that up-regulation of EBP50 could obviously slow the growth of HCC derived from SMMC7721 cells(     

Roles of BN52021 in platelet-activating factor pathway in inflammatory MS1 cells

AIM: To determine the effects of BN52021 on platelet-activating factor receptor (PAFR) signaling molecules under lipopolysaccharide (LPS)-induced inflammatory conditions in MS1 cells. METHODS: MS1 cells (a mouse pancreatic islet endothelial cell line) were grown in Dulbecco’s modified Eagle’s medium supplemented with 10% fetal bovine serum, 2 mmol/L glutamine and 100 μg/mL penicillin/streptomycin in 5% CO 2 at 37 ℃. After growth to confluency in media, the cells were processed for subsequent studies. The MS1 cells received 0, 0.1, 1 and 10 μg/mL LPS in this experiment. The viability/prolifera-tion of the cells induced by LPS was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Apoptosis and necrosis of the cells under the inflammatory condition described previously were observed using Hoechst 33342-propidium iodide staining. Adenylate cyclase (AC), phospholipase A 2 (PLA 2 ), phospholipase Cβ (PLCβ), protein tyrosine kinase (PTK), G protein-coupled receptor kinases (GRK) and p38-mitogen-activated protein kinase (p38 MAPK) mRNA in the PAFR signaling pathway were measured by real-time polymerase chain reaction. The protein expression level of phosphorylated AC (p-AC), phosphorylated PLA 2 (p-PLA 2 ), phosphorylated PTK (p-PTK), phosphorylated p38 MAPK (p-p38 MAPK), PLCβ and GRK was measured using Western blotting analysis. RESULTS: The activity of MS1 cells incubated with dif- ferent concentrations of LPS for 6 h decreased significantly in the 1 μg/mL LPS group (0.49 ± 0.10 vs 0.67 ± 0.13, P < 0.05) and 10 μg/mL LPS group (0.44 ± 0.10 vs 0.67 ± 0.13, P < 0.001), but not in 0.1 μg/mL group. When the incubation time was extended to 12 h (0.33 ± 0.05, 0.32 ± 0.03 and 0.25 ± 0.03 vs 0.69 ± 0.01) and 24 h (0.31 ± 0.01, 0.29 ± 0.03 and 0.25 ± 0.01 vs 0.63 ± 0.01), MS1 cell activity decreased in all LPS concentration groups compared with the blank control (P < 0.001). BN52021 significantly improved the cell activity when its concentration