Effects of oridonin on invasion and migration of human hepatocellular carcinoma MHCC-97H cells

AIM: To investigate the effects of oridonin on the invasion and migration of hepatocelluar carcinoma cells. METHODS: Human hepatocelluar carcinoma MHCC-97H cells were cultured and treated with 5, 10 or 20 μmol/L oridonin. The migration ability was measured by wound healing assay. The invasion ability was examined by Transwell invasion assay. The adhesion capabilities were evaluated by adhesion assay. The protein levels of LIM kinase-1 (LIMK-1), cofilin and phosphorylated cofilin (p-cofilin) were determined by Western blot. RESULTS: Oridonin inhibited the migration, invasion and adhesion abilities of MHCC-97H cells in a dose-dependent manner (P<0.05). After oridonin treatment, the expression of cofilin had no obvious change, but the protein levels of LIMK-1 and p-cofilin decreased significantly. CONCLUSION: Oridonin inhibits the invasion and migration of MHCC-97H cells. The mechanism may be related with the regulatory effect of oridonin on LIMK-1/cofilin signal transduction pathway.     

Effect of luteolin on TGF-β1-induced epithelial-mesenchymal transition in lung cancer A549 cells

AIM:To investigate the effects of luteolin on the invasion and epithelial-mesenchymal transition (EMT) induced by transforming growth factor-β1 (TGF-β1) in lung cancer A549 cells. METHODS:The effect of luteolin at 5, 10, 20, 40, 80 and 160 μmol/L on the viability of A549 cells was measured by MTT assay. The invasion ability was analyzed by Transwell method. The morphological changes of the A549 cells were observed under microscope.The protein expression of E-cadherin and vimentin in the A549 cells were determined by Western blot. RESULTS:The viability of the A549 cells was significantly inhibited by luteolin in a dose-time dependent manner (P<0.05). The IC₅₀ of luteolin for the A549 cells (24 h) was 68.79 μmol/L, while that (48 h) was 47.86 μmol/L. TGF-β1 induced morphological alteration of the A549 cells from epithelial to mesenchymal forms. Luteolin significantly inhibited TGF-β1-induced invasion of the A549 cells (P<0.01). The protein expression of E-cadherin was significantly down-regulated and the protein expression of vimentin was significantly up-regulated in the presence of TGF-β1 at 5 μg/L (P<0.01). However, luteolin reversed TGF-β1-induced EMT, up-regulation of E-cadherin and down-regulation of vimentin (P<0.01). CONCLUSION:Lu-teolin reverses TGF-β1-induced EMT in the lung cancer A549 cells.     

Effect of toosendanin on invasion and migration of human ovarian cancer cells

AIM: To investigate the effect of toosendanin (TSN) on invasion and migration abilities of human ovarian cancer cells and the related mechanism. METHODS: The human ovarian cancer cell lines CAVO-3 and SKVO-3 were treated with TSN at different concentrations. The cell viabilty at 12, 24, 48, 72 and 96 h after TSN treatment was measured by CCK-8 assay. Scratch wound healing assay and Transwell assay were employed to measure the invasion and migration abilities of CAVO-3 cells. The protein expression of nuclear factor-κB (NF-κB) p65, E-cadherin, N-cadherin, vimentin and Snail was determined by Western blot. RESULTS: TSN significantly inhibited the viability of CAVO-3 and SKVO-3 cells (P<0.05). Compared with control group, the migration and invasion abilities of CAVO-3 cells in TSN group decreased significantly (P<0.05). In addition, the expression of NF-κB p65 and E-cadherin protein increased notably, followed with N-cadherin, vimentin and Snail protein decreased significantly (P<0.05). However, the inhibitor of NF-κB BAY11-7082 reversed the impact above. Compared with TSN group, the migration and invasion abilities in TSN+BAY11-7082 group increased significantly (P<0.05). The protein expression of E-cadherin also decreased notably, followed with the protein expression of N-cadherin, vimentin and Snail increased significantly (P<0.05). CONCLUSION: TSN inhibits the invasion and migration abilities of human ovarian cancer cells, which is related to the inhibition of epithelial-mesenchymal transition process mediated by NF-κB/Snail signaling pathway.     

Dickkopf-1 silencing inhibits invasion and epithelial-mesenchymal transition in gastric carcinoma cells by down-regulating β-catenin

AIM: To explore the expression of Dickkopf-1 (DKK1) in human gastric carcinoma cells, and the influences of DKK1 gene silencing on cell invasion. METHODS: The levels of DKK1 in the human gastric mucosa cell line GES-1 and gastric carcinoma cell lines MKN-45 and SGC-7901 were detected by real-time PCR and Western blot. DKK1 gene was silenced by RNA interference, which was verified by real-time PCR, Western blot and ELISA. The cell invasion ability was determined by Transwell assay, and the cell proliferation was inhibited by mitomycin C. The levels of E-cadherin, N-cadherin, vimentin and β-catenin were determined by real-time PCR and Western blot. RESULTS: The expression of DKK1 was significantly higher in MKN-45 cells and SGC-7901 cells than that in GES-1 cells, indicating that DKK1 expression was obviously increased in gastric carcinoma cells. After successful silencing of DKK1 gene in the MKN-45 cells and SGC-7901 cells, the cell invasion ability was markedly decreased in a time-dependent pattern with increased expression of E-cadherin and decreased expression of N-cadherin and vimentin, indicating that DKK1 silencing dramatically inhibited gastric carcinoma cell invasion and epithelial-mesenchymal transition (EMT). The introduction of exogenous recombinant DKK1 (rDKK1) demonstrated the promoting effect of DKK1 on gastric carcinoma cell invasion and EMT. In addition, the inhibitory effects of DKK1 silencing on gastric carcinoma cell invasion and EMT were fulfilled by down-regulating β-catenin. CONCLUSION: The expression of DKK1 is significantly increased in human gastric carcinoma cells. Silencing of DKK1 markedly inhibits gastric carcinoma cell invasion and EMT by down-regulating β-catenin.     

Reverse effect of shikonin on epithelial-mesenchymal transition induced by HGF in lung cancer cells

AIM:To investigate the effects of shikonin on the migration, invasion and epithelial-mesenchymal transition (EMT) in human non-small-cell lung cancer PC9 cells induced by hepatocyte growth factor (HGF). METHODS:The effect of shikonin on the viability of PC9 cells was measured by MTT assay. The cell migration and invasion abilities were analyzed by wound healing assay and Transwell method, respectively. The protein expression levels of E-cadherin, N-cadherin and vimentin in the PC9 cells were determined by Western blot. RESULTS:The viability of PC9 cells was significantly inhibited by shikonin in a dose-dependent manner (P<0.01), with IC₅₀ at 9.364 μmol/L. HGF significantly promoted the abilities of migration and invasion, and induced EMT in the PC9 cells. Shikonin significantly inhibited HGF-induced migration and invasion in the PC9 cells. The expression of E-cadherin was significantly down-regulated and the expression of N-cadherin and vimentin was significantly up-regulated in the presence of HGF (50 μg/L). However, shikonin reversed HGF-induced EMT, as indicated by up-regulation of E-cadherin and down-regulation of N-cadherin and vimentin (P<0.01). CONCLUSION:Shikonin reverses HGF-induced EMT in lung cancer PC9 cells.     

Effects of SphK1 and FAK on epithelial-mesenchymal transition in colon cancer HCT116 cells

AIM: To investigate the effects of sphingosine kinase l(SphK1) and focal adhesion kinase(FAK) on the epithelial-mesenchymal transition(EMT) of human colon cancer HCT116 cells. METHODS: Human colon cancer HCT116 cells were divided into 3 groups. N, N-dimethylsphingosine(DMS) was used to suppress the activity of SphK1. PF573228 was used to suppress the activation of FAK. The cells treated with equal volume of culture medium severed as control group. The cell viability was measured by MTT assay. The protein expression of SphK1, FAK and the EMT relative protein E-cadherin, N-cadherin, vimentin and matrix metalloproteinase(MMP) 2 was analyzed by Western blot. The mRNA expression of SphK1, sphingosine-1-phosphate(S1P), FAK, E-cadherin and vimentin was detected by real-time PCR. The ability of tumor cell migration was measured by wound-healing assay. RESULTS: The cell viability of HCT116 cells was suppressed by DMS and PF573228 in dose and time dependent manners. DMS significantly suppressed the expression of SphK1, FAK, N-cadherin, vimentin and MMP2, meanwhile enhanced the expression of E-cadherin. PF573228 reduced the expression of FAK, SphK1, N-cadherin, vimentin and MMP2, meanwhile increased the expression of E-cadherin(P<0.01). In addition, the migration ability of HCT116 cells was significantly decreased by treating with DMS and PF573228(P<0.01). Compared with control group, the mRNA expression of FAK, SphK1, S1P and vimentin was decreased, while the expression of E-cadherin was increased significantly in PF573228 group and DMS group(P<0.05). CONCLUSION: SphK1 and FAK signaling pathways may play an important role in the occurrence of EMT in the colon cancer HCT116 cells.     

Preliminary exploration for effect of EphA2 on drug resistance of colorectal carcinoma cells

AIM: To investigate the effect of Eph receptor A2 (EphA2) on drug resistance of colorectal carcinoma cells and its possible mechanisms. METHODS: Real-time PCR and Western blot were used to detect the expression of EphA2 at mRNA and protein levels in LoVo and LoVo/5-FU cells. EphA2 siRNA was transfected to down-regulate the EphA2 expression in LoVo/5-FU cells, and the drug sensitivity was calculated by CCK-8 assay. Meanwhile, cell migration and invasion were measured by wound healing assay and Transwell assay, and the protein levels of E-cadherin, β-catenin, N-cadherin, vimentin, Notch and Snail were determined by Western blot. RESULTS: The expression of EphA2 at both mRNA and protein levels was significantly up-regulated in LoVo/5-FU cells (P<0.05). Knockdown of EphA2 suppressed the cell viability, and migration and invasion abilities, but promoted drug sensitivity of LoVo/5-FU cells. Up-regulation of E-cadherin and β-catenin, and down-regulation of N-cadherin and vimentin were observed, indicating that the epithelial-mesenchymal transition (EMT) process was suppressed. Knockdown of EphA2 decreased the expression levels of Notch and Snail. CONCLUSION: Down-regulation of EphA2 partly reverses drug resistance of LoVo/5-FU cells. The mechanism may be related to suppressing cell growth, migration, invasion and EMT process via Notch/Snail signaling pathway.     

Mechanism of microRNA-138-5p inhibiting proliferation,migration and invasion of lung cancer cells

AIM: To investigate the mechanism of microRNA-138-5p (miR-138-5p) inhibiting the proliferation, migration and invasion abilities of lung cancer cells.METHODS: The lung cancer A549 and H460 cells were transfected with miR-NC (control group) or miR-138-5p (experimental group). The bioinformatic analysis was performed to predict the target genes of miR-138-5p.The expression levels of miR-138-5p, forkhead box protein C1 (FOXC1) mRNA and vimentin mRNA were detected by RT-qPCR. The protein expression of FOXC1, vimentin, E-cadherin, N-cadherin and β-catenin was determined by Western blot. MTS method and colony formation assay were used to detect cell viability and proliferation ability. Wound healing assay and Transwell assay were used to detect cell migration and invasion ability.RESULTS: Over-expression of miR-138-5p significantly reduced the expression of FOXC1 and vimentin at mRNA and protein levels (P<0.05). The expression of E-cadherin and β-catenin were up-regulated and the expression of N-cadherin was down-regulated. The proliferation, migration and invasion abilities of the lung cancer cells were inhibited by the over-expression of miR-138-5p.CONCLUSION: miR-138-5p inhibits the proliferation, migration and invasion abilities of lung cancer cells by targeting FOXC1 and vimentin. It may be a potential target for lung cancer gene therapy.     

PTBP1 promotes migration and invasion of liver cancer cells through EMT pathway

AIM: To investigate the molecular mechanism of polypyrimidine tract-binding protein 1 (PTBP1) promoting the migration and invasion of hepatoma cells. METHODS: The differentially expressed splicing proteins in different cell lines were screened by qPCR and Western blot. The difference of the expression of PTBP1 between liver cancer and normal liver tissues was analyzed by bioinformatics. Wound-healing and Transwell assays were used to study the effect of PTBP1 on the migration and invasion of hepatoma cells, and Western blot was used to detect the effect of PTBP1 on epithelial-mesenchymal transition (EMT) signaling pathway. RESULTS: Compared with the HepG2 cells, the expression of splicing factor PTBP1 was significantly increased in the HCCLM3 cells with high metastatic ability (P<0.05), and the expression level of PTBP1 in hepatocellular carcinoma tissues was significantly higher than that in normal tissues (P<0.05). Over-expression of PTBP1 significantly increased the migration and invasion of HCCLM3 cells (P<0.05), increased the expression of mesenchymal marker proteins N-cadherin and vimentin (P<0.05), and promoted the EMT process of liver cancer cells. CONCLUSION: PTBP1 promotes the migration and invasion of liver cancer cells by promoting the EMT pathway of liver cancer cells.     

Effect of digoxin on hypoxia-induced epithelial-mesenchymal transition and invasion in human breast carcinoma MCF-7 cells

AIM: To investigate the effect of digoxin on hypoxia-induced epithelial-mesenchymal transition (EMT), migration and invasion in human breast carcinoma MCF-7 cells. METHODS: MCF-7 cells were treated in vitro with a chemical hypoxia inducer cobalt chloride (CoCl₂) to imitate hypoxia. Cell migration was observed by wound healing assay, and cell invasion was measured by Transwell invasion assay. The protein levels of hypoxia-inducible factor-1α (HIF-1α), Snail, E-cadherin and vimentin in MCF-7 cells were detected by Western blot. RESULTS: Digoxin inhibited CoCl₂-induced EMT and reversed the mesenchymal phenotype. CoCl₂ enhanced the abilities of migration and invasion (P<0.01), significantly decreased the expression of E-cadherin and increased the expression of HIF-1α, Snail and vimentin (P<0.01), but these effects were blocked by digoxin. CONCLUSION: Digoxin inhibits CoCl₂-induced EMT and invasion most likely via HIF1-α-Snail signaling pathway.     

Effect of Aurora protein kinase inhibitor VX-680 on homogeneity adhesion and migration in human hepatoma HepG2 cell

AIM:To study the effect of Aurora protein kinase inhibitor VX-680 on homogeneous adhesion and migration ability in human hepatocellular carcinoma cell line HepG2. METHODS:The HepG2 cell were divided into experimental group and control group, respectively. VX-680 was used in experimental groups at 3 concentrations (3.125 μmol/L group, 6.25 μmol/L group and 12.5 μmol/L group). DMSO was used in the control group. The effects of VX-680 at different concentrations on the adhesion ability of human hepatocellular carcinoma HepG2 cells were observed by cell slow aggregation test and separation experiment. The effects of VX-680 at different concentrations on the migration ability of HepG2 cells was detected by wound healing assay. The expression of E-cadherin in HepG2 cells was detected by Western blot. RESULTS:The results of the slow aggregation test showed that compared with the control group, the number of cell clumps formed in experimental groups was significantly decreased (P<0.01). The results of separation experiment showed that the ratio of N_TC/N_TE gradually decreased with the increased concentration of VX-680. The results of wound healing assay showed that as the concentration of VX-680 increased, the cell scratch healing ability gradually weakened compared with control group. The results of Western blot showed that the protein expression of E-cadherin in the HepG2 cells increased with the increased concentration of VX-680 (P<0.05). CONCLUSION:VX-680 increases the homogeneous adhesion and inhibits the migration of HepG2 cells.     

Down-regulation of lncRNA PCAT1 suppresses oral squamous cell carcinoma cell proliferation,growth, invasion,migration and epithelial-mesenchymal transition

AIM: To investigate the effects of the long non-coding RNA (lncRNA) PCAT1 on the oral squamous cell carcinoma (OSCC) cell proliferation, growth, invasion and migration, and to explore the underlying mechanisms. METHODS: The PCAT1 siRNA was transfected by Lipofectmine 2000, and RT-qPCR and Western blot were performed to determine the mRNA and protein expression of relevant genes, respectively. CCK-8 assay and colony formation assay were used to measure OSCC cell proliferation and growth, respectively. The cell invasion and migration assays were used to measure the invasive and migratory abilities of the OSCC cells, respectively. RESULTS: PCAT1 was significantly up-regulated in OSCC tissues and cells compared with normal adjacent tissues and normal human oral keratinocyte cells, respectively (P<0.05). PCAT1 siRNA transfection suppressed the expression of PCAT1 in Tca8113 and TSCCa cells (P<0.05). Knockdown of PCAT1 in Tca8133 cells and TSCCa cells significantly suppressed the cell proliferation, invasion and migration abilities (P<0.05). In addition, knockdown of PCAT1 in Tca8133 cells and TSCCa cells also suppressed the mRNA and protein levels of ZEB-1, N-cadherin and vimentin, and increased the mRNA and protein expression of E-cadherin (P<0.05). CONCLUSION: Knockdown of PCAT1 suppresses cell proliferation and migration abilities, and the effect of PCAT1 on OSCC cells may be associated with epithelial-mesenchymal transition.     

Effect of insulin resistance on biological function of HepG2 cells and sensitivity to cisplatin

AIM: To investigate the effect of insulin resistance (IR) on the biological function of hepatocellular carcinoma (HCC) and sensitivity to cisplatin. METHODS: IR was induced in HepG2 cells via incubation with a high concentration of insulin. Afterwards, the effects of IR on adhesion, migration, invasion and sensitivity to cisplatin of the cells were detected.RESULTS: The results indicated that glucose consumption was reduced in the IR cells. The expression of the insulin receptor and glucose transporter 2 was down-regulated. Furthermore, HepG2/IR cells displayed markedly enhanced adhesion, migration, and invasion. These cells exhibited a lower sensitivity to cisplatin. On the contrary, HepG2/IR cells exhibited decreased adhesion and invasion after treatment with the insulin sensitizer pioglitazone hydrochloride.CONCLUSION: IR is closely related to drug resistance, adhesion, migration and invasion in HepG2 cells. These findings may help explain the clinical observation of the limited efficacy of chemotherapy on a background of IR.     

Role of up-regulated microRNA145 in viability,apoptosis, invasion and metastasis of hepatoma cells

AIM: To investigate the effects of microRNA145 (miRNA145) on the viability, apoptosis, invasion and metastasis of hepatoma HepG2 cells. METHODS: HepG2 cells were randomly allocated into 3 groups: blank control group, empty mimic transfected group and miRNA145 mimic transfected group. Under the induction of Lipofectamine^TM 2000, the recombinant was transfected into HepG2 cells. After transfection, the expression level of miRNA145 was detected by real-time PCR. The protein level of N-cadherin and the mRNA expression levels of miRNA145 and N-cadherin were detected by Western blot and real-time PCR. The cell viability was detected by MTS assay. The cell cycle and apoptosis were analyzed by flow cytometry. Invasion and metastasis were detected by Transwell assay. RESULTS: Compared with negative control, miRNA145 expression was up-regulated significantly, while the expression of N-cadherin was down-regulated significantly. Meanwhile, the cell viability, cell cycle, apoptosis, invasion and metastasis of hepatoma HepG2 cells were all significantly inhibited (P<0.05). CONCLUSION: miRNA145 dramatically inhibits viability, apoptosis, invasion and metastasis of hepatoma cells.     

Chronic hypoxia enhances aggressiveness of MCF-7 breast cancer cells through EMT

AIM: To investigate the effects of chronic hypoxia on the aggressiveness of MCF-7, a human breast cancer cell line, and the underlying mechanisms.METHODS: MCF-7 cells were cultured under hypoxia (1% O₂, 5% CO₂ and 94% N₂) or control (95% O₂ and 5% CO₂) condition. The viability, proliferation, and invasion and migration abilities of the MCF-7 cells were determined by MTT assay, CCK-8 assay, cell counting, and cell invasion and migration assays. Anchorage-independent growth and the alteration of cellular polarization of the MCF-7 cells were tested by soft agar colony formation assay and Matrigel-3D culture assay, respectively. The effects of chronic hypoxia on the growth and metastasis of MCF-7 cells in vivo were investigated by xenograft in nude mice. The morphological changes of the MCF-7 cells were observed under an inverted microscope. Hypoxia-induced alterations in the levels of hypoxia inducible factor-1 (HIF-1) and phosphorylated glycogen synthase kinase-3β (p-GSK-3β) as well as epithelial-mesenchymal transition (EMT) molecules, such as E-cadherin, N-cadherin, vimentin, matrix metalloproteinase (MMP)-3 and MMP-9, were determined by Western blot.RESULTS: Chronic hypoxia significantly increased the viability, proliferation, and invasion and migration abilities of MCF-7 cells in vitro, enhanced the anchorage-independent growth, facilitated cellular polarization alteration in Matrigel-3D culture, and promoted cancer metastasis in vivo. Hypoxia up-regulated HIF-1, activated GSK-3β, down-regulated E-cadherin and increased the protein levels of N-cadherin, vimentin, MMP-3 and MMP-9. CONCLUSION: Chronic hypoxia enhances the aggressiveness of breast cancer cells probably through EMT.     

Effect of HC-1119 on biological behaviors of triple-negative breast cancer BT549 cells

AIM: To explore the effect of new artificially synthesized androgen receptor (AR) antagonist HC-1119 on the biological function of triple-negative breast cancer (TNBC) BT549 cells and the molecular mechanism. METHODS: The AR expression was assessed in different human breast cancer cell lines MDA-MB-231, T47D, MCF-7, SKBR3 and BT549 by Western blot. The TNBC BT549 cells with AR positive expression were treated with HC-1119. The cell viability was measured by CCK-8 assay. The apoptosis rate and cell cycle distribution were analyzed by flow cytometry. The migration and invasion abilities were detected by Transwell assay in vitro. The protein expression of E-cadherin, vimentin and P21 was determined by Western blot. RESULTS: AR was positively expressed in BT549 cells. HC-1119 inhibited the cell viability in a time-and dose-dependent manner (P<0.05), increased the percentage of apoptotic cells and the percentage of S-phase cells significantly, repressed the migration and invasion abilities (P<0.05), and decreased P21 expression at protein level (P<0.01). No influence on the expression of E-cadherin and vimentin in the BT549 cells was observed. CONCLUSION: AR antagonist HC-1119 decreases the viability, migration ability and invasion ability, enhances the apoptosis, and arrests the cell cycle distribution of TNBC BT549 cells. HC-1119 represses the viability of BT549 cells by down-regulating P21 expression, while the process of epithelial-mesenchymal transition is not involved in the inhibition of cell migration.     

Effect of HMGB1 expression knockdown on invasion ability of breast cancer cells induced by TNF-α

AIM:To investigate the effect of high-mobility group box-1 (HMGB1) expression knockdown on the invasion ability of breast cancer cells induced by tumor necrosis factor-α (TNF-α). METHODS:HMGB1 siRNA was used to transfect into the breast cancer MDA-MB-231 cells. The expression of HMGB1 at mRNA and protein levels was determined by RT-qPCR and Western blot. After the MDA-MB-231 cells with HMGB1 expression knockdown were treated with TNF-α, the apoptosis rate was analyzed by flow cytometry, the cell invasion ability was measured by Transwell assay, and the cell migration ability was detected by cell scratch test. The protein expression of E-cadherin, MMP-2, N-cadherin, MMP-9 and Bax was determined by Western blot. RESULTS:The expression of HMGB1 at mRNA and protein levels in the MDA-MB-231 cells transfected with HMGB1 siRNA was significantly lower than that in the non-transfected cells (P<0.05). The apoptosis rate in the cells was increased after TNF-α treatment, and the cell invasion and migration abilities were also increased. The protein level of E-cadherin in the cells was decreased, the protein level of N-cadherin was increased, and the protein levels of MMP-2, MMP-9 and Bax were also increased (P<0.05). After the MDA-MB-231 cells with HMGB1 expression knockdown were induced by TNF-α, the apoptotic rate was increased, the invasion and migration abilities were decreased, the protein levels of E-cadherin and Bax were increased, and the protein levels of N-cadherin, MMP-2 and MMP-9 were decreased, as compared with the cells only induced by TNF-α without knockdown of HMGB1 expression (P<0.05). CONCLUSION:Knockdown of HMGB1 expression enhances the apoptosis of breast cancer cells induced by TNF-α, and inhibited the cell invasion, migration and epithelial-mesenchymal transition induced by TNF-α. The mechanism may be related with the changes of protein expression of MMP-2, MMP-9 and Bax.     

Effects of TRPC1 on TGF-β1-induced migration of human bronchial epithelial cells

AIM: To investigate the role of canonical transient receptor potential channel 1 (TRPC1) in the migration of human bronchial epithelial cells (16HBE) induced by transforming growth factor-β1 (TGF-β1). METHODS: Silencing of TRPC1 gene expression was performed by siRNA. The cell activity and apoptosis were measured by CCK-8 assay and flow cytometry, respectively. The migration and invasion abilities of the 16HBE cells were detected by wound- healing assay and Transwell assay. The protein expression of E-cadherin and vimentin was determined by Western blot. RESULTS: TGF-β1 treatment significantly enhanced the cell migration distance compared with control groups (P < 0.01). The results of CCK-8 assay and flow cytometry indicated that there were no significant difference in proliferation and apoptosis among TRPC1 siRNA group, TGF-β1 group and control group (P > 0.05). The results of wound-healing and Transwell assays showed that migration and invasion abilities in TRPC1 siRNA + TGF-β1 group were markedly suppressed compared with TGF-β1 group (P < 0.01). The protein expression of E-cadherin and vimentin induced by TGF-β1 was inhibited by TRPC1 silencing compared with TGF-β1 group (P < 0.05). CONCLUSION: TRPC1 is involved in the migration of human bronchial epithelial cells induced by TGF-β1 through regulating the protein expression of E-cadherin and vimentin.     

X-ray ionizing radiation induces epithelial-mesenchymal transition in human nasopharyngeal carcinoma CNE-2 cells

AIM:To investigate the effect of X-ray ionizing radiation on epithelial-mesenchymal transition (EMT) in human nasopharyngeal carcinoma CNE-2 cells and its involved potential signaling pathway. METHODS:The nasopharyngeal carcinoma CNE-2 cells were irradiated with different doses (0 Gy, 2 Gy, 4 Gy and 8 Gy) of X-ray. The morphological changes of the cells were observed under inverted microscope after 24 h. The migration and invasion abilities were detected by wound healing and Transwell assays. The mRNA and protein levels of E-cadherin, N-cadherin and vimentin in nasopharyngeal carcinoma CNE-2 cells were determined by real-time PCR and Western blot, respectively. The protein levels of Akt and p-Akt were detected by Western blot. RESULTS:After X-ray irradiation, the CNE-2 cells exhibited typical ‘cobblestone’ or spindle-like shape, with extended pseudopodia and dilated intercellular space. The invasiveness and metastatic abilities of the CNE-2 cells were enhanced (P<0.01). The mRNA and protein expression levels of E-cadherin were significantly decreased (P<0.01), while the mRNA and protein expression levels of N-cadherin and vimentin were markedly increased after irradiation as compared with the control group (no irradiation) (P<0.05). The protein level of p-Akt was significantly enhanced (P<0.01), while the protein level of Akt showed little change after irradiation. CONCLUSION:X-ray ionizing radiation induces EMT in nasopharyngeal carcinoma CNE-2 cells, which may be related to the activation of PI3K/Akt signaling pathway.     

Calreticulin promotes migration and invasion of nasopharyngeal carcinoma cells by inducing cell EMT

AIM:To observe the expression of calreticulin (CRT) in nasopharyngeal carcinoma tissues, analyze the significance of clinical pathology and the influence on epithelial-mesencymal transition (EMT) of CNE2 cells. METHODS:The expression of calreticulin was detected by immunohistochemistry in 52 nasopharyngeal carcinoma and 57 nasopharyngeal benign tissues, and the significance of clinical pathology was evaluated. The calreticulin gene-specific small interfering RNA was constructed, and then was transfected into the NPC cell line CNE2 using the cationic liposome method. The effect of CRT on the morphological changes of the CNE2 cells was observed under light microscope. The effect of CRT on the cell migration and invasion abilities of the CNE2 cells was detected by Transwell migration and invasion assays. The expression of EMT-related proteins E-cadherin, vimentin, transforming growth factor (TGF)-β and matrix metalloproteinase (MMP)-9 in the CNE2 cells was determined by Western blot. RESULTS:The positive expression rate of CRT in the benign lesion tissues was 19.29% (11/57), which was significantly increased in the nasopharyngeal carcinoma tissues as 82.69% (43/52). The expression rate of CRT was positively correlated with the stage of nasopharyngeal carcinoma and lymph node metastasis (P<0.05). Knockdown of CRT expression made the CNE2 cells showing a spindle shape to a flat, cobblestone-like epithelial state change, arranged more compact, and the migration and invasion abilities were significantly decreased (P<0.05). Knockdown of CRT expression resulted in significant increase in the protein expression of E-cadhe-rin, and the decreases in the protein expression of vimentin, TGF-β and MMP-9 in the CNE2 cells (P<0.05). CONCLUSION:Calreticulin expression in nasopharyngeal carcinoma is significantly higher and positively correlated with nasopharyngeal carcinoma stage and lymph node metastasis. Calreticulin promotes cell migration and invasion of nasopharyngeal carcinoma CNE2 cells by inducing EMT.