Effects of HuR on cell viability,migration and invasion of gastric cancer cell line MGC-803

AIM:To investigate the effects of HuR on cell function of gastric cancer cell line MGC-803. METHODS:The mRNA expression level of HuR was detected by RT-qPCR in the tumor samples of 80 gastric cancer patients diagnosed clinically. HuR gene knock-down was achieved by transfection of si-HuR into the MGC-803 cells. The invasion, migration and viability of MGC-803 cells were measured by the scratch wound hearing, Transwell and CCK-8 assays, respectively. RESULTS:High mRNA expression of HuR was observed in 67 cases (84%) of gastric cancer tissues as compared with their control samples. Furthermore, knock-down of HuR expression effectively inhibited the invasion, migration and viability of the MGC-803 cells (P<0.05), indicating that HuR play an important role in gastric cancer as an oncogene. CONCLUSION:Abnormal expression of HuR is correlated with the progression of gastric cancer. Knock-down of HuR expression inhibits the invasion, migration and viability of MGC-803 cells.     

miRNA-101-3p inhibits proliferation and migration of gastric cancer cells by targeting EZH2

AIM: To investigate the role of microRNA-101-3p (miRNA-101-3p) on the proliferation, apoptosis and invasion of gastric cancer cells and the possible regulatory mechanisms. METHODS: The expression of miRNA-101-3p in two kinds of gastric cancer cells and a gastric mucosal cell line was detected by real-time PCR. The miRNA-101-3p was overexpressed by Lipofectamine 2000 transfection with miRNA-101-3p mimics. The effects of miRNA-101-3p on cell cycle distribution and apoptosis were analyzed by flow cytometry. The effects of miRNA-101-3p on cell proliferation and migration abilities were detected by CCK-8 assay, trypan blue exclusion test and Transwell assay. The protein expression of enhancer of zeste homolog 2 (EZH2) was determined by Western blot. RESULTS: The expression of miRNA-101-3p in gastric cancer cells was lower than that in gastric mucosal cells (P<0.05). The gastric cancer cell MGC-803 had the lowest expression level of miRNA-101-3p. The result of flow cytometry showed that the population of S phase was reduced, and the population of G₀/G₁ phase and the early stage apoptotic rate were increased after the expression of miRNA-101-3p was overexpressed (P<0.05). The results of CCK-8 assay, trypan blue exclusion test and Transwell assay showed that overexpression of miRNA-101-3p significantly reduced the proliferation and migration abilities of gastric cancer cells (P<0.05). Overexpression of miRNA-101-3p decreased the protein level of EZH2 (P<0.05). CONCLUSION: miRNA-101-3p may suppresses the gastric cancer cell proliferation and migration, and promotes the gastric cancer cell apotosis by down-regulation of EZH2.     

MicroRNA-330 inhibits growth and migration of gastric cancer cells by directly targeting EGR-2

AIM:To explore the function and significance of microRNA-330 (miR-330) in the development of gastric cancer. METHODS:Forty-eight cases of gastric cancer tissues and paired adjacent tissues were collected in Department of Oncology, Affiliated Hospital of Gansu University of Chinese Medicine, and the expression levels of miR-330 were detected by RT-qPCR. The expression levels of miR-330 in the gastric cancer cells and human gastric epithelial GES-1 cells were evaluated by RT-qPCR. The viability, colony formation and migration of gastric cancer cells after transfected with miR-330 inhibitor or miR-330 mimic were analyzed by CCK-8 assay, colony formation assay and Transwell assay, respectively. Furthermore, miR-330 target gene was predicted by miRanda target gene prediction database. RESULTS:miR-330 expression was down-regulated both in gastric cancer tissues and gastric cancer cells (P<0.05). The expression levels of miR-330 were negatively associated with the tumor size, lymph metastasis, pathological grade stage and T stage (P<0.05). The viability, colony formation and migration of gastric cancer cells were significantly increased after transfected with miR-330 inhibitor (P<0.05). However, the viability, colony formation and migration of gastric cancer cells were significantly decreased after transfected with miR-330 mimic (P<0.05). Furthermore, EGR-2 was the direct target gene of miR-330. CONCLUSION:miR-330 suppresses gastric cancer cell growth and migration, and the mechanism may be related to its direct target gene EGR-2, suggesting that miR-330 may be used as a potential new target for diagnosis and targeted therapy for gastric cancer.     

STC-1 mediates proliferation and apoptosis of gastric cancer cells through Bcl-2

AIM To investigate the effect of stanniocalcin-1 （STC-1） on the proliferation and apoptosis of gastric cancer AGS cells and the role of Bcl-2 in these processes. METHODS The AGS cells were transfected with the plasmids for STC-1 knockdown or over-expression. The cell proliferation was measured by MTT assay and colony formation assay. The migration ability was detected by scratch assay. Apoptosis was analyzed by Hoechst 33342 staining and flow cytometry with annexin V-FITC/PI double staining. The protein expression of Bcl-2, survivin, caspase-3 and cleared caspase-3 was determined by Western blot. The mRNA expression levels of STC-1 and Bcl-2 in 20 cases of clinical gastric cancer tissues and adjacent tissues were detected by RT-qPCR, and the correlation between them was analyzed by Pearson method. RESULTS After over-expression of STC-1, the proliferation and migration abilities of the AGS cells were increased, the expression of Bcl-2 and survivin was increased, while the expression of caspase-3 and cleared caspase-3 was decreased （P<0.05）. After knockdown of STC-1, the proliferation and migration abilities of the AGS cells were decreased, the expression of Bcl-2 and survivin was decreased, while the expression of caspase-3 and cleared caspase-3 was increased （P<0.05）. The mRNA expression levels of STC-1 and Bcl-2 in the gastric cancer tissues were higher than those in the adjacent tissues. Pearson correlation analysis showed that there was a positive correlation between STC-1 and Bcl-2 mRNA expression in the cancer tissues （r=0.308, P=0.011）. CONCLUSION STC-1 may regulate the biological function of gastric cancer cells by altering the expression level of Bcl-2.     

Effects of RARG on viability and migration ability of gastric cancer cells

AIM:To investigate the effect of retinoic acid receptor gamma (RARG) on the viability and migration ability of gastric cancer cells. METHODS:The expression of RARG in gastric cancer and normal gastric tissues and its correlation with the overall survival rate of gastric cancer patients were analyzed by bioinformatics. The expression of RARG was promoted and inhibited by over-expression plasmid transfection and RNA interference technique in gastric can-cer cells in vitro, respectively. MTT and Transwell assays were used to detect the effect of RARG on the viability and migration ability of gastric cancer cells. The effect of RARG on regulating the Wnt/β-catenin signaling pathway was evaluated by Western blot and TOP/FOP dual-luciferase reporter assay. The protein interaction of RARG and β-catenin was determined by co-immunoprecipitation and immunofluorescence co-localization assay. RESULTS:Over-expression of RARG enhanced the viability and migration ability of gastric cancer SGC7901 cells (P<0.05). Knockdown of RARG attenuated the viability and migration ability of gastric cancer MGC-803 cells (P<0.05). At the same time, RARG over-expression increased the protein expression levels of β-catenin, c-Myc, cyclin D1, Twist and Snail (P<0.05), and the activity of TOP/FOP dual-luciferase reporter gene (P<0.05). In addition, RARG interacted with β-catenin protein in the gastric cancer cells. CONCLUSION:RARG promotes the viability and migration ability of gastric cancer cells via activating the Wnt/β-catenin signaling pathway, thus playing an important role in the development of gastric cancer.     

PGRN gene silencing on proliferation and migration abilities of human non-small-cell lung cancer A549 cells

AIM: To investigate the effect of small interfering RNA (siRNA)-mediated progranulin (PGRN) gene silencing on the proliferation and migration abilities of human non-small-cell lung cancer A549 cells and its mechanism. METHODS: The mRNA and protein expression levels of PGRN in the A549 cells and human bronchial epithelial (HBE) cells were detected by qPCR and Western blot. A549 cells were transfected with PGRN-siRNA by liposome method. The expression of PGRN at mRNA and protein levels in the A549 cells transfected with PGRN-siRNA was detected by qPCR and Western blot, respectively. The cell viability was measured by MTT assay. The cell proliferation ability was measured by living cells counting and crystal violet staining assays. The cell migration ability was measured by wound-healing and Transwell assays. The protein levels of proliferating cell nuclear antigen (PCNA), cyclin D1, Bcl-2 and Bax were determined by Western blot. The protein levels of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and phosphorylated protein kinase B (p-Akt) were also determined by Western blot. RESULTS: The expression of PGRN at mRNA and protein levels was higher in the A549 cells than that in the HBE cells (P<0.05). The expression of PGRN at mRNA and protein levels in the A549 cells transfected with PGRN-siRNA was significantly decreased, and the cell proliferation and migration abilities were significantly decreased. The protein expression levels of PCNA, cyclin D1 and Bcl-2 were significantly reduced and the protein expression level of Bax was significantly increased (P<0.05). Meanwhile, the protein levels of p-ERK1/2 and p-Akt were down-regulated (P<0.05). CONCLUSION: PGRN gene silencing obviously inhibits the proliferation and migration abilities of human non-small-cell lung cancer A549 cells. The PI3K/Akt and MAPK/ERK signaling pathways may play an important role in these processes.     

Effects of β3Gn-T8 on proliferation of gastric cancer AGS cells

AIM: To study the effects of β1,3-N-acetylglucosaminyltransferase 8 (β3Gn-T8) on the biological behaviors of gastric cancer cells and xenograft tumors. METHODS: After pEGFP-C1-β3Gn-T8 was transfected into human gastric adenocarcinoma AGS cells, the cell proliferation was measured by MTT assay and viable cell counting with trypan blue exclusion, and the apoptotic rate was analyzed by flow cytometry. The model of AGS cell subcutaneous xenograft was established to detect the growth of the xenograft. RESULTS: The proliferation of AGS cells transfected with pEGFP-C1-β3Gn-T8 was significantly increased (P < 0.05), but the apoptotic rate was not significantly changed. The growth rate and final volume of xenograft tumor in pEGFP-C1-β3Gn-T8 group were significantly higher than those in control group (P < 0.05). CONCLUSION: β3Gn-T8 promotes the proliferation of gastric cancer AGS cells and significantly increases the growth of AGS cell xenograft tumor.     

miR-15a-5p inhibits proliferation and migration of human hepatocellular carcinoma SMMC-7721 cells

AIM: To observe the influence of high expression of miR-15a-5p on the proliferation and migration of human hepatocellular carcinoma SMMC-7721 cells.METHODS: The miR-15a-5p oligonucleotide, which was reconstructed with additional restriction sites of EcoR Ⅰ and Hind Ⅲ, was chemically synthesized and confirmed by sequencing. The miR-15a-5p eukaryotic expression system was constructed by pcDNA6.2-GW/Em-GFP-pre-miR-15a-5p plasmid. The miR-15a-5p was transfected into the SMMC-7721 cells transiently by plasmid, and quantified by quantitative real-time PCR at the mRNA level. The cell viability was measured by CCK-8 assay, and the living cell counting was performed by the method of Trypan blue exclusion. The migration ability of the SMMC-7721 cells with high expression of miR-15a-5p was detected by wound healing test.RESULTS: The sequence of miR-15a-5p oligonucleotide 100% matched the designed sequence. Compared with control group, the miR-15a-5p expression was increased significantly (P<0.05). The viability, the living cell number and the migration ability of the SMMC-7721 cells were decreased in high expression of miR-15a-5p group with statistically significant difference (P<0.05).CONCLUSION: The abilities of proliferation and migration in human hepatocellular carcinoma SMMC-7721 cells are decreased by high expression of miR-15a-5p.     

Expression of miRNA-22 in ovarian cancer and effect of miRNA-22 over-expression on SKOV-3 ovarian cancer cell proliferation,migration and invasion

AIM: To examine the expression of miRNA-22 in the ovarian tissues and the effect of miRNA-22 over-expression on the proliferation, migration and invasion in SKOV-3 cells. METHODS: The expression levels of miRNA-22 in different ovarian tissues and SKOV-3 cells were determined by qPCR. miRNA-22 was over-expressed by transfection of miRNA-22 mimic. The cell viability was examined by CCK-8 assay. The cell migration was measured by wound healing test. The cell invasion was analyzed by Transwell assay. The protein expression levels of VEGF and P53 were determined by Western blot. RESULTS: Compared with the normal ovarian tissue, the expression level of miRNA-22 was remarkably decreased in the ovarian tumor tissues. After transfection with miRNA-22 mimic, the expression level of miRNA-22 in the SKOV-3 cells was significantly increased, while the cell viability, migration and invasion were obviously decreased. Moreover, the protein expression of VEGF and P53 was dramatically inhibited after over-expression of miRNA-22. CONCLUSION: The decreased miRNA-22 expression may be correlated with the development of ovarian can-cer. Over-expression of miRNA-22 decreases the cell viability, migration and invasion by reducing the protein expression of VEGF and P53.     

Sinomenine inhibits viability,migration and invasion of human ovarian cancer SKOV3 cells

AIM:To investigate the effect of sinomenine on the viability, migration and invasion of human ovarian cancer SKOV3 cells and its possible mechanism. METHODS:The SKOV3 cells were treated with sinomenine at different concentrations for 12 h, 24 h and 48 h. CCK-8 assay was employed to detect the effects of sinomenine on the viability of the SKOV3 cells. Flow cytometry was used to analyze the cell cycle distribution. The cell migration and invasion abilities were measured by Transwell assay. Western blot was used to determine the protein levels of cyclin A, cyclin D1, E-cadherin and matrix metalloproteinase-9 (MMP-9). RESULTS:Sinomenine remarkably inhibited the viability of SKOV3 cells and IOSE80 cells in a time-dependent and dose-dependent manner (P<0.05), and the IC₅₀ values of 48 h were 2.12 mmol/L and 17.35 mmol/L, respectively. In a dose-dependent manner, sinomenine induced G₀/G₁ and S phase arrest in SKOV3 cells (P<0.05), suppressed the migration and invasion abilities of SKOV3 cells (P<0.05), down-regulated the protein levels of cyclin A, cyclin D1 and MMP-9 (P<0.05), and up-regulated the protein level of E-cadherin (P<0.05). CONCLUSION:Sinomenine inhibits the viability, migration and invasion of human ovarian cancer SKOV3 cells most likely via down-regulation of the protein levels of cyclin A, cyclin D1 and MMP-9, and up-regulation of the protein level of E-cadherin.     

Baicalein induces autophagy in breast cancer cells

AIM:To investigate the autophagy of breast cancer cells induced by baicalein and to explore its mechanism.METHODS:The effects of baicalein on the viability of MCF-7 cells and 4T1 cells were investigated by MTT assay,and the dosage of the drug was determined.The expression levels of microtubule-associated protein 1 light chain 3-Ⅱ(LC3-Ⅱ) and LC3-I in the MCF-7 cells and 4T1 cells treated with baicalein at doses of 25,50 and 100 μmol/L,or combined with autophagy inhibitor 3-methyladenine (3-MA) were determined by Western blot.In order to confirm the role of baicalein in autophagy,the effect of 3-MA on the apoptosis of both MCF-7 cells and 4T1 cells induced by baicalein was analyzed by flow cytometry.The protein levels of p-mTOR,mTOR,p-AKT and AKT were examined by Western blot and the role of AKT-mTOR pathway in the induction of autophagy in breast cancer induced by baicalein was determined by the combination of activators.RESULTS:Baicalein at 50 μmol/L and above doses significantly inhibited the viability of breast cancer cells in a dose-and time-dependent manner.The expression of LC3-Ⅱ/LC3-I in both MCF-7 cells and 4T1 cells was significantly enhanced after the action of baicalein,and the ratio of LC3-Ⅱ/LC3-I was significantly decreased after 3-MA addition.The results of flow cytometry showed that,compared with baicalein group,the combination of baicalein and 3-MA promoted the levels of necrosis and apoptosis.Moreover,the protein levels of p-mTOR and p-AKT were significantly decreased and were rescued by EGF,while their total protein levels were not changed.CONCLUSION:Baicalein induces autophagy through AKT-mTOR pathway both in MCF-7 cells and 4T1 cells.     

Effect of annexin A2 on proliferation,migration and apoptosis of human cervical cancer HeLa cells

AIM：To explore the effect of annexin A2 (ANXA2) on the proliferation, migration and apoptosis abilities of human cervical cancer HeLa cells. METHODS：Overexpression vectors and siRNA of ANXA2 were constructed, and then transfected into HeLa cells. The HeLa cells were divided into 4 groups:control group, scramble group, ANXA2 overexpression group and ANXA2-siRNA group. The expression of ANXA2 at mRNA and protein levels was examined by real-time PCR and Western blotting. MTT assay, Boyden chamber and flow cytometry were used to determine the effect of ANXA2 on the proliferation, migration and apoptosis abilities of the HeLa cells. RESULTS：The proliferation and migration of HeLa cells were obviously promoted by ANXA2 overexpression. The proliferation and migration of HeLa cells were remarkably inhibited by the transfection of ANXA2-siRNA. ANXA2 had no effect on apoptosis of HeLa cells. CONCLUSION:Silencing of ANXA2 effectively inhibits the proliferation and migration of cervical cancer cells, but has little effect on apoptosis. ANXA2 may play a pivotal role in the occurrence and development of cervical cancer, and may be used as a molecular target for the treatment of cervical cancer.     

Niflumic acid inhibits the proliferation,migration and invasion of glioma U87 cells

AIM To investigate the effect of niflumic acid （NFA） on human glioma U87 cells and to clarify the potential mechanism. METHODS The U87 cells were cultured in vitro and divided into blank control group, and 50, 100 and 200 μmol/L NFA groups. MTT assay was performed to determine the viability of cells in various groups. Migration and invasion abilities were measured by real-time cell analysis （RTCA）. RESULTS The results of MTT assay showed that compared with blank control group, the viability of U87 cells was increased after treatment with NFA for 12 h （P<0.05 or P<0.01）, while the viability was significantly decreased after treatment with NFA for 24 and 48 h （P<0.05 or P<0.01） in a concentration-dependent manner. The results of RTCA showed that compared with control group, the cell migration and invasion abilities were inhibited in 100 and 200 μmol/L NFA groups （P<0.05 or P<0.01） and the inhibitory effects were more obvious in 200 μmol/L NFA group （P<0.01）. CONCLUSION NFA inhibits the viability, migration and invasion of human glioma U87 cells.     

lncRNA-MALAT1 targets and downregulates miR-570-3p expression to promote proliferation of gastric cancer cells

AIM:To investigate whether long non-coding RNA MALAT1 (lncRNA-MALAT1) targets and down-regulates microRNA-570-3p (miR-570-3p) expression to further promote the proliferation of gastric cancer cells. METHODS:Gastric cancer cell line SGC7901 was cultured in vitro and divided into 3 groups:blank control, si-MALAT1 and si-MALAT1 NC. The si-MALAT1 and si-MALAT1 NC groups were transfected with MALAT1 siRNA and its negative control, respectively. The cell proliferation was evaluated by MTS assay. The expression of miR-570-3p was detected at different time points in the pure SGC7901 gastric cancer cell line, and the expression of lncRNA-MALAT1 and miR-570-3p in different groups was detected by RT-qPCR. The potential complementary binding sites of lncRNA-MALAT1 and miR-570-3p were predicted by RegRNA. The MALAT1 gene and its mutant fragment were cloned into luciferase reporter vector psiCHECK-2. Restriction enzyme analysis and sequencing were used to identify whether the recombinant plasmids carrying MALAT1 or MALAT1-Mut were successfully constructed. miR-570-3p mimic, miR-570-3p inhibitor, miR-570-3p mimic negative control and miR-570-3p inhibitor negative control were co-transfected into the 293T cells with the luciferase repor-ters containing MALAT1 or MALAT1-Mut. Dual-luciferase reporter assay was performed to detect luciferase activity in different groups in order to verify the relationship between lncRNA-MALAT1 and miR-570-3p. RESULTS:Compared with blank control group and si-MALAT1 NC group, the A₄₉₀ value in si-MALAT1 group was significantly decreased (P<0.01). The expression of miR-570-3p presented an obvious declining trend over time. The expression of lncRNA-MALAT1 in si-MALAT1 group was remarkably decreased, whereas the expression of miR-570-3p was obviously increased. The dual-luciferase reporter assay indicated that the MALAT1 reporter luciferase activity decreased significantly in miR-570-3p mimic group compared with mimic negative control (P<0.01), and the luciferase activity of MALAT1 reporter was obviously up-regulated in miR-570-3p inhibitor group compared with miR-570-3p mimic group (P<0.01). However, miR-570-3p mi-mic, miR-570-3p inhibitor, miR-570-3p mimic negative control and miR-570-3p inhibitor negative control showed no effect on the luciferase activity of MALAT1-Mut reporter. CONCLUSION:lncRNA-MALAT1 targets and down-regulates miR-570-3p expression to further promote the proliferation of gastric cancer cells.     

miR-105 inhibits cell proliferation,migration and invasion abilities in non-small-cell lung cancer cells by targeting and negative regulation of KIFC1

AIM:To study the effects of microRNA-105(miR-105) on the cell proliferation, migration and invasion abilities of non-small-cell lung cancer (NSCLC) H460 cells, and further to explore its mechanism. METHODS:The expression of miR-105 and kinesin family member C1 (KIFC1) mRNA in the NSCLC tissues and adjacent tissues and cells was detected by RT-qPCR. The protein expression of KIFC1 in the NSCLC tissues, adjacent normal tissues and cells was determined by Western blot. The H460 cells were divided into miR-105 group (transfection with miR-105 mimics), miR-negative control (NC) group (transfection with miR-NC), inhibitor-NC group (transfection with NC of inhibitor), inhibitor-miR-105 group (transfection with miR-105 inhibitor), si-NC group (transfection with NC siRNA), si-KIFC1 group (transfection with KIFC1 siRNA), miR-105+vector group (miR-105 mimics and pcDNA 3.1 co-transfection) and miR-105+KIFC1 group (miR-105 mimics and pcDNA 3.1-KIFC1 co-transfection). The cell proliferation was measured by MTT assay and colony formation assay. The migration and invasion abilities were detected by Transwell methods. The relative luciferase acitivity was evaluated by double luciferase reporter assay. RESULTS:Compared with the adjacent tissues, the expression of miR-105 was significantly decreased and the expression of KIFC1 was significantly increased in NSCLC tissues (P<0.05). Compared with human normal embryonic lung fibroblasts MRC-5, the expression of miR-105 in the H460 cells was significantly decreased, and the expression of KIFC1 was significantly increased (P<0.05). miR-105 inhibited the relative luciferase activity of H460 cells with wild-type KIFC1 and negatively regulated the protein expression of KIFC1. Over-expression of miR-105 and knockdown of KIFC1 expression significantly inhibited the proliferation, migration and invasion abilities of H460 cells. Over-expression of KIFC1 reversed the inhibitory effect of miR-105 on the cell proliferation, migration and invasion abilities of H460 cells. CONCLUSION:miR-105 inhibits the proliferation, migration and invasion abilities of NSCLC cells. The mechanism may be related to targeting and negatively regulating expression of KIFC1.     

Curcumin inhibits migration and invasion of lung cancer PC-9 cells via down-regulation of nectin-4 expression

AIM: To investigate the effects of curcumin on the abilities of migration and invasion in the lung cancer PC-9 cells, and to observe the relationship between curcumin and nectin-4 expression.METHODS: The viability, migration and invasion of lung cancer PC-9 cells treated with curcumin or transfected with siNectin-4 were measured by MTT assay, wound healing test and Transwell assay, respectively. The protein levels of nectin-4, p-AKT and AKT in the PC-9 cells treated with curcumin or transfected with siNectin-4 were detected by Western blot.RESULTS: Curcumin inhibited the viability of PC-9 cells. The wound healing rates and the numbers of the transmembrane cells in curcumin 10 μmol/L and 20 μmol/L groups were decreased compared with control group without curcumin treatment. The expression level of nectin-4 was reduced after curcumin treatment for 24 h. The viability of the PC-9 cells was significantly inhibited after transfected with siNectin-4 for 48 h or 72 h (P<0.01), and the wound healing rates was decreased in siNectin-4 group compared with NC group (P<0.01). The numbers of the transmembrane cells in siNectin-4 group was significantly reduced (P<0.01). Curcumin and knockdown of nectin-4 suppressed the activation of AKT pathway in PC-9 cells. In siNectin-4+curcumin group, the cell viability reduced compared with curcumin group, and wound healing rates, cell invasive ability and AKT phosphorylation levels were decreased.CONCLUSION: Curcumin inhibits migration and invasion of the lung cancer PC-9 cells via down-regulation of nectin-4 expression and inhibition of AKT pathway.     

Kaempferol inhibits cell proliferation,invasion and migration via Wnt/β-catenin signaling in HBx-HepG2 cells

AIM: To explore the effects of kaempferol on the proliferation, invasion and migration abilities of HBx-HepG2 cells and to examine the underlying molecular mechanisms. METHODS: The expression levels of related genes at mRNA and protein levels were determined by RT-qPCR and Western blot. The cell apoptotic rate was analyzed by flow cytometry. The cell proliferation, growth, invasion and migration abilities were measured by MTT assay, colony formation assay, Transwell invasion assay and wound healing assay, respectively. RESULTS: Kaemferol inhibited HBx-HepG2 cell proliferation in a concentration-and time-dependent manner. Kaempferol at 100 μmol/L significantly inhibited the colony formation, invasion and migration abilities of the HBx-HepG2 cells. Kaemferol at 100 μmol/L also increased cell apoptotic rate, increased the protein levels of cleaved caspase-3, cleaved caspase-9 and Bax, and decreased the expression level of Bcl-2. In addition, kaemferol at 100 μmol/L suppressed the mRNA and protein expression levels of β-catenin, c-Myc and cyclin D1 in the HBx-HepG2 cells. Kaemferol at 100 μmol/L also suppressed the protein level of p-GSK-3β and the β-catenin protein levels in both cytoplasm and nucleus. LiCl treatment reversed the inhibitory effect of kaempferol on the growth, invasion and migration of the HBx-HepG2 cells. CONCLUSION: Kaempferol inhibits cell proliferation, invasion and migration via activating Wnt/β-catenin signaling in HBx-HepG2 cells.     

Promoting cell viability and migration of gastric cancer cells by PRRX2 via activation of Wnt/β-catenin signaling pathway

AIM: To study the effect of paired-related homeobox 2 (PRRX2) gene on the viability and migration ability of gastric cancer cells, and to analyze the underlying mechanism of regulating Wnt/β-catenin signaling pathway.METHODS: The expression of PRRX2 in gastric cancer and normal gastric tissue and the correlation between PRRX2 expression in gastric cancer tissues with the overall survival rate of gastric cancer patients were analyzed by bioinformatics. The small interfering RNA (siRNA) and over-expressed plasmids of PRRX2 were transfected into gastric cancer cells MGC-803 and SGC-7901, respectively. MTT assay and Transwell assay were used to detect the viability and migration ability of gastric cancer cells. Western blot and TOPflash/FOPflash dual-luciferase reporter gene assay were used to detect the activity of Wnt/β-catenin signaling pathway. Co-immunoprecipitation was used to detected the interaction between PRRX2 and β-catenin proteins.RESULTS: Knockdown of PRRX2 attenuated the viability and migration ability of gastric cancer cell line MGC-803 (P<0.05). Over-expression of PRRX2 enhanced the viability and migration ability of SGC-7901 cells (P<0.05), increased the protein levels of β-catenin, c-Myc and cyclin D1 (P<0.05) and the activity of TOPflash/FOPflash dual-luciferase reporter gene (P<0.05). PRRX2 interacted with β-catenin protein in gastric cancer cells.CONCLUSION: PRRX2 promotes the viability and migration ability of gastric cancer cells, which may be related to Wnt/β-catenin signaling pathway.     

CHK1 inhibitor SCH900776 suppresses proliferation and migration of U251 cells

AIM: To investigate the effect of SCH900776, an inhibitor of checkpoint kinase 1 (CHK1), on the proliferation and migration abilities of human glioma U251 cells.METHODS: The cell viability was detected by MTT assay, and cell proliferation was determined by cell colony formation assay. Cell cycle distribution was analyzed by flow cytometry. Wound healing assay was used to determine the cell migration ability. The protein levels were determined by Western blot.RESULTS: SCH900776 inhibited the growth of U251 cells in a dose-dependent manner (P<0.05). SCH900776 treatment substantially induced U251 cell cycle arrest in S and G₂/M phases by decreasing the level of cell division cycle protein 2 (Cdc2) and p-Cdc2. Moreover, SCH900776 inhibited the cell migration. Western blot results indicated that SCH900776 increased the phosphorylation level of p38 MAPK and inhibited the activation of Akt.CONCLUSION: SCH900776 inhibits the proliferation and migration abilities in human U251 cells by promoting the phosphorylation of p38 MAPK and suppressing the activation of Akt.