FoxM1 overexpression promotes epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma

AIM: To investigate the expression of forkhead box protein M1(Fox M1) in the process of epithelial mesenchymal transition in hepatocellular carcinoma(HCC) and its role in metastasis.METHODS: Fox M1 and E-cadherin expression in HCC tissue microarray specimens was evaluated by immunohistochemical staining,and statistical methods were applied to analyze the correlation between FoxM 1 and epithelial-mesenchymal transition(EMT).KaplanMeier analysis of the correlation between the Fox M1 expression level and recurrence or overall survival of HCC patients was performed.The expression of FoxM 1,E-cadherin and snail homologue 1(SNAI1) in HCC cell lines was evaluated by real-time reverse transcriptionpolymerase chain reaction and Western blot.Hepatocyte growth factor(HGF) was used to induce EMT and stimulate cell migration in HCC cells.The expression of Fox M1 and SNAI1 was regulated by transfection with plasmids pc DNA3.1 and si RNAs in vitro.The occurrence of EMT was evaluated by Transwell assay,morphologic analysis and detection of the expression of EMT markers(E-cadherin and vimentin).Luciferase and chromatin immunoprecipitation assays were used to evaluate whether SNAI1 is a direct transcriptional target of FoxM 1.RESULTS: FoxM 1 expression was increased significantly in HCC compared with para-carcinoma(10.7 ± 0.9 vs 8.2 ± 0.7,P < 0.05) and normal hepatic(10.7 ± 0.9 vs 2.7 ± 0.4,P < 0.05) tissues.Overexpression of Fox M1 was correlated with HCC tumor size,tumor number,macrovascular invasion and higher TNM stage,but was negatively correlated with E-cadherin expression in microarray specimens and in cell lines.Fox M1 overexpression was correlated significantly with HCC metastasis and EMT.In vitro,we found that FoxM 1 plays a key role in HGF-induced EMT,and overexpression of Fox M1 could suppress E-cadherin expression and induce EMT changes,which were associated with increased HCC cell invasiveness.Next,we confirmed that FOXM1 directly binds to and activates the SNAI1 promoter,and we identified SNAI1 as a direct transcriptional target of FOXM1.Moreover,inhibiting the expression of SNAI1 significantly inhibited FoxM 1-mediated EMT.CONCLUSION: Fox M1 overexpression promotes EMT and metastasis of HCC,and SNAI1 plays a critical role in FoxM 1-mediated EMT.

Hydrogen-rich water protects against acetaminopheninduced hepatotoxicity in mice

AIM: To investigate the hepatoprotective effects and mechanisms of hydrogen-rich water(HRW) in acetaminophen(APAP)-induced liver injury in mice.METHODS: Male mice were randomly divided into the following four groups: normal saline(NS) control group, mice received equivalent volumes of NS intraperitoneally(ip); HRW control group, mice were given HRW(same volume as the NS group); APAP + NS group, mice received NS ip for 3 d(5 mL /kg body weight, twice a day at 8 am and 5 pm) after APAP injection; APAP + HRW group, mice received HRW for 3 d(same as NS treatment) after APAP challenge.In the first experiment, mice were injected ip with a lethal dose of 750 mg/kg APAP to determine the 5-d survival rates.In the second experiment, mice were injected ip with a sub-lethal dose of 500 mg/kg.Blood and liver samples were collected at 24, 48, and 72 h after APAP injection to determine the degree of liver injury.RESULTS :Treatment with HRW resulted ina significant increase in the 5-d survival rate compared with the APAP + NS treatment group(60% vs 26.67%, P < 0.05).HRW could significantly decrease the serum alanine aminotransferase level(24 h: 4442 ± 714.3 U/L vs 6909 ± 304.8 U/L, P < 0.01; 48 h: 3782 ± 557.5 U/L vs 5111 ± 404 U/L, P < 0.01; and3255 ± 337.4 U/L vs 3814 ± 250.2 U/L, P < 0.05, respectively) and aspartate aminotransferase level(24 h: 4683 ± 443.4 U/L vs 5307 ± 408.4 U/L, P < 0.05; 48 h: 3392 ± 377.6 U/L vs 4458 ± 423.6 U/L, P < 0.01; and 3354 ± 399.4 U/L vs 3778 ± 358 U/L, respectively) compared with the APAP treatment group.The alkaline phosphatase, total bilirubin and lactate dehydrogenase levels had the same result.Seventy-two hours after APAP administration, liver samples were collected for pathological examination and serum was collected to detect the cytokine levels.The liver index(5.16% ± 0.26% vs 5.88% ± 0.073%, P < 0.05) and percentage of liver necrosis area(27.73% ± 0.58% vs 36.87% ± 0.49%, P < 0.01) were significantly lower in the HRW-treated animals.The malonyldialdehyde(MDA) contents were significantly reduced in the HRW pretreatment group, but they were increased in the APAP-treated group(10.44 ± 1.339 nmol/mg protein vs 16.70 ± 1.646 nmol/mg protein, P < 0.05).A decrease in superoxide dismutase(SOD) activity in the APAP treatment group and an increase of SOD in the HRW treatment group were also detected(9.74 ± 0.46 U/mg protein vs 12.1 ± 0.67 U/mg protein, P < 0.05).Furthermore, HRW could significantly increase the glutathione(GSH) contents(878.7 ± 76.73 mg/g protein vs 499.2 ± 48.87 mg/g protein) compared with the APAP treatment group.Meanwhile, HRW could reduce the inflammation level(serum TNF-α: 399.3 ± 45.50 pg/L vs 542.8 ± 22.38 pg/L, P < 0.05; and serum IL-6: 1056 ± 77.01 pg/L vs 1565 ± 42.11 pg/L, P < 0.01, respectively).In addition, HRW could inhibit 4-HNE, nitrotyrosine formation, JNK phosphorylation, connexin 32 and cytochrome P4502 E expression.Simultaneously, HRW could facilitate hepatocyte mitosis to promote liver regeneration.CONCLUSION: HRW has significant therapeutic potential in APAP-induced hepatotoxicity by inhibiting oxidative stress and inflammation and promoting liver regeneration.

Experimental study of the critical sand starting velocity of gas-watersand flow in an inclined pipe

The purpose of this paper is to study the critical sand starting velocity and transformation law of flow pattern based on gas-water-sand three-phase flow in an inclined pipe.Firstly,the indoor simulation experiment system of gas-water-sand three-phase flow was used to test the conversion law of flow pattern based upon the different gas void fraction.Secondly,the influence of slug bubbles on sand migration was investigated according to distinctive hole deviation angles,gas void fraction and sand concentration.Finally,the critical sand starting velocity was tested based on dissimilar hole deviation angles,gas void fraction,sand concentration and sand particle size,and then the influence of the abovementioned key parameters on the sand starting velocity was debated based on the force analysis of the sand particles.The experimental results illustrated that when the gas void fraction was less than 5%,it was bubbly flow.When it increased from 5%to 30%,the bubbly flow and slug flow coexisted.When it was between 30%and 50%,the slug flow and agitated flow coexisted.When it reached 50%,it was agitated flow.Providing that the hole deviation angle was 90°,the phenomenon of overall migration and wavelike migration on the surface of sand bed was observed.On the contrary,the phenomenon of rolling and jumping migration was recognized.The critical sand starting velocity was positively correlated with the hole deviation angle and sand particle size,but negatively associated with the gas void fraction and sand concentration.This research can provide a certain reference for sand-starting production in the field of petroleum engineering.