Guggulsterone induces apoptosis of human hepatocellular carcinoma cells through intrinsic mitochondrial pathway

AIM: To investigate the effects of guggulsterone on the proliferation and apoptosis of human hepatoma Hep G2 cells in vitro and relevant mechanisms.METHODS: Human hepatocellular carcinoma Hep G2 cells and normal human liver L-02 cells were treated with different concentrations of guggulsterone(5-100 μmol/L) for 24-72 h. Cell proliferation was tested by MTT assay. Cell cycle and apoptosis were investigated using flow cytometry(FACS). Bcl-2 and Bax m RNA and protein expression was detected by real-time PCR and Western blot, respectively. TGF-β1, TNF-α, and VEGF contents were determined by ELISA.RESULTS: Guggulsterone significantly inhibited Hep G2 cell proliferation in a dose- and time-dependent manner. FACS showed that guggulsterone arrested Hep G2 cell cycle at G0/G1 phase. Guggulsterone induced apoptosis was also observed in Hep G2 cells, with 24.91% ± 2.41% and 53.03% ± 2.28% of apoptotic cells in response to the treatment with 50 μmol/L and 75 μmol/L guggulsterone, respectively. Bax m RNA and protein expression was significantly increased and Bcl-2 m RNA and protein expression was decreased. ELISA analysis showed that the concentrations of TGF-β1 and VEGF were significantly decreased and TNF-α concentration was increased.CONCLUSION: Guggulsterone exerts its anticancer effects by inhibiting cell proliferation and inducing apoptosis in Hep G2 cells. Guggulsterone induces apoptosis by activation of the intrinsic mitochondrial pathway.     

疏肝健脾方含药血清对酒精性损伤HepG2细胞脂肪变性的保护作用

目的探讨疏肝健脾方含药血清对酒精性损伤HepG2细胞脂肪变性的保护作用。方法采用酒精诱导HepG2细胞损伤模型,设立正常对照组、模型组、含药血清组（疏肝健脾方含药血清）和正常血清组,观察HepG2细胞形态以及生长情况;采用MTT法检测细胞活力,采用油红O染色对存活HepG2细胞脂肪变程度进行观察和量化比较,采用免疫印迹法检测HepG2细胞过氧化物酶体增殖物激活受体（PPAR）γ蛋白表达水平。结果含药血清组细胞形态与正常对照组HepG2细胞形态相似,细胞形态完整,贴壁生长状态良好;含药血清组和正常对照组HepG2细胞脂肪变程度十分接近,脂肪变程度较轻;油红O染色显示,异丙醇溶液脱色后吸光度测定值在模型组为（0.942±0.051）,正常血清组为（0.928±0.049）,均显著高于含药血清组（0.619±0.043）和正常对照组【（0.621±0.050,P<0.05】;MTT吸光度值在正常对照组为（1.021±0.071）,在含药血清组为（0.962±0.066）,也显著高于模型组（0.561±0.035）和正常血清组【（0.572±0.041）,P<0.05】;正常对照组和含药血清组HepG2细胞PPARγ蛋白表达水平显著低于模型组和正常血清组（P<0.05）。结论疏肝健脾方含药血清对酒精性损伤HepG2细胞脂肪变性有保护作用。     

Effect of interferon-γ and tumor necrosis factor-α on hepatitis B virus following lamivudine treatment

AIM: To evaluate anti-hepatitis B virus (HBV) activity and cytotoxicity of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) following lamivudine treatment of HepG2.2.15 cells.METHODS: HepG2.2.15 cells were treated with 2 μmol/L lamivudine for 16 d (lamivudine group), cultured for 10 d, followed by 5 ng/mL TNF-α and 1000 U/mL IFN-γ for 6 d (cytokine group), or treated with 2 μmol/L lamivudine for 10 d followed by 5 ng/mL TNF-α and 1000 U/mL IFN-γ for 6 d (sequential group), or cultured without additions for 16 d (control group). Intracellular DNA was extracted from 3 × 10⁵ HepG2.2.15 cells from each group. The extracted DNA was further purified with mung bean nuclease to remove HBV relaxed circular DNA that may have remained. Both HBV covalently closed circular DNA (cccDNA) and HBV DNA were examined with real-time polymerase chain reaction. The titers of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were quantified with enzyme-linked immunosorbent assay. Cell viability was measured with the cell counting kit-8 assay.RESULTS: Compared to lamivudine alone (22.63% ± 0.12%), both sequential (51.50% ± 0.17%, P = 0.034) and cytokine treatment (49.66% ± 0.06%, P = 0.041) showed a stronger inhibition of HBV cccDNA; the difference between the sequential and cytokine groups was not statistically significant (51.50% ± 0.17% vs 49.66% ± 0.06%, P = 0.88). The sequential group showed less inhibition of HBV DNA replication than the lamivudine group (67.47% ± 0.02% vs 82.48% ± 0.05%, P = 0.014); the difference between the sequential and cytokine groups was not statistically significant (67.47% ± 0.02% vs 57.45% ± 0.07%, P = 0.071). The levels of HBsAg and HBeAg were significantly decreased in the sequential treatment group compared to the other groups [HBsAg: 3.48 ± 0.04 (control), 3.09 ± 0.08 (lamivudine), 2.55 ± 0.13 (cytokine), 2.32 ± 0.08 (sequential), P = 0.042 for each between-group comparison; HBeAg: 3.48 ± 0.01 (control), 3.08 ± 0.08 (lamivudine), 2.57 ± 0.15 (cytokine), 2.34 ± 0.12 (sequential), P = 0.048 for each between-group comparison]. Cell viability in the cytokine group was reduced to 58.03% ± 8.03% compared with control cells (58.03% ± 8.03% vs 100%, P = 0.000). Lamivudine pretreatment significantly reduced IFN-γ + TNF-α-mediated toxicity of HepG2.2.15 cells [85.82% ± 5.43% (sequential) vs 58.03% ± 8.03% (cytokine), P = 0.002].CONCLUSION: Sequential treatment overcame the lower ability of lamivudine alone to inhibit cccDNA and precluded the aggressive cytotoxicity involving IFN-γ and TNF-α by decreasing the viral load.     

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(     

Growth inhibitory effects of Phyllanthus niruri extracts in combination with cisplatin on cancer cell lines

AIM:To investigate the cytotoxic effects of spray-dried extracts of Phyllanthus niruri in combination with cisplatin on two cancer cell lines.METHODS:Colorectal carcinoma(HT29) and human hepatocellular carcinoma(HepG2) cells were treated with spray-dried extracts of Phyllanthus niruri(SDEPN) either alone or in combination with cisplatin at different concentrations(0.5 mg/mL and 1 mg/mL) for 4 h and 24 h.To verify and quantify cancer cells treated with these products as well as identify the cell cycle stage and cell viability,we stained the cells with propidium iodide and assessed them by flow cytometry.The percentage of cells in different cell cycle phases was quantified and data were expressed as histograms.Significant differences between groups were determined using analysis of variance and Bonferroni's test,as indicated.A value of P 0.05 was considered to be statistically significant.RESULTS:SDEPN had significantly different cytotoxic effects on HT29(2.81 ± 0.11 vs 3.51 ± 1.13,P 0.05) and HepG2(5.07 ± 0.3 vs 15.9 ± 1.04,P 0.001) cells when compared to control cells for 4 h.SDEPN also had significantly different cytotoxic effects on HT29(1.91 ± 0.57 vs 4.53 ± 1.22,P 0.05) and HepG2(14.56 ± 1.6 vs 35.67 ± 3.94,P 0.001) cells when compared to control cells for 24 h.Both cell lines were killed by cisplatin in a dose-dependent manner compared to control cells(HepG2 cells for 4 h:10.78 ± 1.58 vs 53.89 ± 1.53,P 0.001;24 h:8.9 ± 1.43 vs 62.78 ± 1.87,P 0.001 and HT29 cells for 4 h:9.52 ± 0.913 vs 49.86 ± 2.89,P 0.001;24 h:11.78 ± 1.05 vs 53.34 ± 2.65,P 0.001).In HT29 cells,pretreatment with SDEPN and subsequent treatment with cis-platin resulted in a greater number of cells being killed(12.78 ± 1.01 vs 93.76 ± 1.6,P 0.001).HepG2 cells showed significant cell killing with treatment with SDEPN when combined with cisplatin(12.87 ± 2.78 vs 78.8 ± 3.02,P 0.001).CONCLUSION:SDEPN is selectively toxic against two cancer cell lines.Moreover,SDEPN in combination with cisplatin induces a synergistic increase in the cell death of both HT29 and HepG2 cells.     

Synergistic anticancer properties of docosahexaenoic acid and 5-fluorouracil through interference with energy metabolism and cell cycle arrest in human gastric cancer cell line AGS cells

AIM: To explore the synergistic effect of docosahexaenoic acid(DHA)/5-fluorouracil(5-FU) on the human gastric cancer cell line AGS and examine the underlying mechanism.METHODS: AGS cells were cultured and treated with a series of concentrations of DHA and 5-FU alone or in combination for 24 and 48 h. To investigate the synergistic effect of DHA and 5-FU on AGS cells, the inhibition of cell proliferation was determined by MTT assay and cell morphology. Flow cytometric analysis was also used to assess cell cycle distribution, and the expression of mitochondrial electron transfer chain complexes(METCs)?Ⅰ, Ⅱ and Ⅴ in AGS cells was further determined by Western blot analysis. RESULTS: DHA and 5-FU alone or in combination could markedly suppress the proliferation of AGS cells in a significant time and dose-dependent manner. DHA markedly strengthened the antiproliferative effect of 5-FU, decreasing the IC50 by 3.56-2.15-fold in an apparent synergy. The morphological changes of the cells were characterized by shrinkage, cell membrane blebbing and decreased adherence. Cell cycle analysis showed a shift of cells into the G0/G1 phase from the S phase following treatment with DHA or 5-FU(G0/G1 phase: 30.04% ± 1.54% vs 49.05% ± 6.41% and 63.39% ± 6.83%, respectively, P 0.05; S phase: 56.76% ± 3.14% vs 34.75% ± 2.35% and 25.63% ± 2.21%, respectively, P 0.05). Combination treatment of DHA and 5-FU resulted in a significantly larger shift toward the G0/G1 phase and subsequent reduction in S phase(G0/G1 phase: 69.06% ± 2.63% vs 49.05% ± 6.41% and 63.39% ± 6.83%, respectively, P 0.05; S phase: 19.80% ± 4.30% vs 34.75% ± 2.35% and 25.63% ± 2.21%, respectively, P 0.05). This synergy was also reflected in the significant downregulation of the expression of METCs in AGS cells.CONCLUSION: Synergistic anticancer properties of DHA and 5-FU may involve interference with energy production of AGS cells via downregulation of METCs and cell cycle arrest.     

miR-363靶向调控E2F3表达影响HepG2细胞增殖和凋亡研究*

目的 探讨微小RNA-363（miR-363）靶向调控E2F转录因子3（E2F3）的表达对HepG2细胞增殖和凋亡的影响。方法 体外培养HepG2细胞,采用Lipofectamine法将miR-363抑制剂或其阴性对照转染到HepG2细胞,继续培养48 h,收获细胞,采用四噻唑蓝（MTT）法测定细胞增殖率,使用流式细胞术法检测细胞凋亡率,采用实时荧光RT-PCR法检测HepG2细胞miR-363 mRNA水平,采用Western Blot法检测HepG2细胞E2F3、BAX和Caspase-3蛋白表达水平。结果 对照组HepG2细胞增殖率为（96.4±9.7)%,显著高于抑制剂处理组【（72.3±6.5）%,P<0.05】,凋亡率为（8.2±1.4）%,显著低于抑制剂处理组【（9.7±0.8）%,P<0.05】;对照组HepG2细胞miR-363 mRNA相对水平为（1.0±0.1）,显著高于抑制剂处理组【（0.6±0.2）,P<0.05】,E2F3蛋白表达量为（1.0±0.1）,显著高于抑制剂处理组【（0.6±0.1）,P<0.05】,而对照组HepG2细胞Bax和Caspase-3蛋白表达量分别为（0.4±0.0）和（0.5±0.1）,均显著低于抑制剂处理组【（0.6±0.1）和（0.7±0.0）,P均<0.05】。结论 miR-363可靶向调控E2F3的表达,抑制HepG2细胞增殖,诱导其凋亡。本研究结果为肝癌靶向治疗提供了一定的理论依据。     

Notch1 downregulation combined with interleukin-24 inhibits invasion and migration of hepatocellular carcinoma cells

AIM: To confirm the anti-invasion and anti-migration effects of down-regulation of Notch1 combined with interleukin(IL)-24 in hepatocellular carcinoma(HCC) cells.METHODS: γ-secretase inhibitors(GSIs) were used to down-regulate Notch1.Hep G2 and SMMC7721 cells were seeded in 96-well plates and treated with GSI-I or/and IL-24 for 48 h.Cell viability was measured by MTT assay.The cellular and nuclear morphology was observed under a fluorescence microscope.To further verify the apoptotic phenotype,cell cultures were also analyzed by flow cytometry with Annexin V-FITC/propidium iodide staining.The expression of Notch1,SNAIL1,SNAIL2,E-cadherin,IL-24,XIAP and VEGF was detected by Western blot.The invasion and migration capacities of HCC cells were detected by wound healing assays.Notch1 and Snail were downregulated by RNA interference,and the target proteins were analyzed by Western blot.To investigate the mechanism of apoptosis,we analyzed Hep G2 cells treated with si Notch1 or si CON plus IL-24 or not for 48h by caspase-3/7 activity luminescent assay.RESULTS: GSI-I at a dose of 2.5 μmol/L for 24 h caused a reduction in cell viability of about 38% in Hep G2 cells.The addition of 50 ng/m L IL-24 in combination with 1 or 2.5 μmol/L GSI-I reduced cell viability of about 30% and 15%,respectively.Treatment with IL-24 alone did not induce any cytotoxic effect.In SMMC7721 cells with the addition of IL-24 to GSI-I(2.5 μmol/L),the reduction of cell viability was only about 25%.Following GSI-I/IL-24 combined treatment for 6 h,the apoptotic rate of Hep G2 cells was 47.2%,while no significant effect was observed in cells treated with the compounds employed separately.Decreased expression of Notch1 and its associated proteins SNAIL1 and SNAIL2 was detected in Hep G2 cells.Increased E-cadherin protein expression was noted in the presence of IL-24 and GSI-I.Furthermore,the increased GSI-I and IL-24 in Hep G2 cell was associated with downregulation of MMP-2,XIAP and VEGF.In the absence of treatment,Hep G2 cells could migrate into the scratched space in 24 h.With IL-24 or GSI-I treatment,the wound was still open after 24 h.And the distance of the wound closure strongly correlated with the concentrations of IL-24 and GSI-I.Treatment of Notch-1 silenced Hep G2 cells with 50 ng/m L IL-24 alone for 48 h induced cytotoxic effects very similar to those observed in non-silenced cells treated with GSI-I/IL-24 combination.Caspase-3/7 activity was increased in the presence of si Notch1 plus IL-24 treatment.CONCLUSION: Down-regulation of Notch1 by GSI-I or si RNA combined with IL-24 can sensitize apoptosis and decrease the invasion and migration capabilities of Hep G2 cells.     

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.     

Anticancer effects of sweet potato protein on human colorectal cancer cells

AIM: To investigate the effects of proteins purified from sweet potato storage roots on human colorectal cancer cell lines. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Hoechst 33258 nuclear staining and Boyden transwell chamber methods were used to determine whether purified sweet potato protein (SPP) from fresh sweet potato roots affected proliferation, migration and invasion, respectively, of human colorectal cancer SW480 cells in vitro . The inhibitory effects of SPP on growth of human colorectal cancer HCT-8 cells intraperitoneally xenografted in nude mice and spontaneous lung metastasis of murine Lewis lung carcinoma 3LL cells subcutaneously transplanted in C57 BL/6 mice were also investigated in vivo . RESULTS: SPP inhibited the proliferation of SW480 cells in a dose-dependent manner, with an IC 50 value of 38.732 μmol/L (r2 = 0.980, P = 0.003) in the MTT assay. Hoechst 33258 nuclear staining further revealed inhibition of cell viability and induction of apoptosis by SPP. The transwell assay disclosed significant reduction in migrated cells/field by 8 μmol/L SPP (8.4 ± 2.6 vs 23.3 ± 5.4, P = 0.031) and invaded cells/field through the ECMatrix by 0.8 μmol/L SPP, compared with the control (25.2 ± 5.2 vs 34.8 ± 6.1, P = 0.038). Both intraperitoneal (ip) and intragastric (ig) administration of SPP led to significant suppression of growth of intraperitoneally inoculated HCT-8 cells in nude mice to 58.0% ± 5.9% (P = 0.037) and 43.5% ± 7.1% (P = 0.004) of the controls, respectively, after 9 d treatment. Bloody ascites additionally disappeared after ip injection of trypsin inhibitor. Notably, ig and ip administration of SPP induced a significant decrease in spontaneous pulmonary metastatic nodule formation in C57 BL/6 mice (21.0 ± 12.3 and 27.3 ± 12.7 nodules/lung vs 42.5 ± 4.5 nodules/lung in controls, respectively, P < 0.05) after 25 d treatment. Moreover, the average weight of primary tumor nodules in the hind leg of mice decreased from 8.2 ± 1.3 g/mice in     

CIAPIN1对HepG2细胞增殖和细胞周期的影响

目的 观察调控细胞因子诱导的凋亡抑制分子1（CIAPIN1）基因表达对肝癌细胞株HepG2细胞增殖的影响,并分析其作用机制。方法 分别构建重组慢病毒CIAPIN1表达载体和CIAPIN1沉默载体,感染HepG2细胞,获得稳定高表达和低表达CIAPIN1基因的细胞后,实验分为4组,即CIAPIN1高表达组、CIAPIN1低表达组、无关沉默RNA（siRNA）干扰组和空白对照组,检测各组细胞增殖及CIAPIN1基因和蛋白表达,使用流式细胞仪检测细胞周期,采用Western blotting法检测cyclinD1、CDK4、cyclin E、CDK2水平以及总蛋白中IKKβ、磷酸化IKBα、p65和磷酸化p65水平。结果 CIAPIN1低表达组细胞增殖受到明显抑制,G0/G1期细胞比例为（73.2±2.5）%,明显高于GIAPIN1高表达组【（58.8±2.2）%,P<0.05】、无关siRNA干扰组【（62.4±1.8）%,P<0.05】或空白对照组【（63.2±2.6）%,P<0.05】;CIAPIN1 高表达组cyclinD1、CDK4、CDK2、cyclinE相对表达量明显高于其它各组,差异有统计学意义（P<0.05）;CIAPIN1高表达组磷酸化IKBα、磷酸化P65相对表达量分别为（1.335±0.182）和（0.731±0.106）,明显高于GIAPIN1低表达组【（0.108±0.035）和（0.028±0.010）,P均<0.05】、无关siRNA干扰组【（0.251±0.082）和（0.318±0.058）,P均<0.05】或空白对照组【（0.238±0.067）和（0.322±0.061）,P均<0.05】。结论 CIAPIN1对肝癌细胞增殖有促进作用,可能与其对NF-кB信号通路的激活作用有关。     

Protection of ghrelin postconditioning on hypoxia/reoxygenation in gastric epithelial cells

AIM: To investigate the protective effect and mechanisms of ghrelin postconditioning against hypoxia/reoxygenation (H/R)-induced injury in human gastric epithelial cells. METHODS: The model of H/R injury was established in gastric epithelial cell line (GES-1) human gastric epithelial cells. Cells were divided into seven groups: normal control group (N); H/R postconditioning group; DMSO postconditioning group (DM); ghrelin postconditioning group (GH); D-Lys3-GHRP-6 + ghrelin postconditioning group (D + GH); capsazepine + ghrelin postconditioning group (C + GH); and LY294002 + ghrelin postconditioning group (L + GH). 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to detect GES-1 cell viability. Hoechst 33258 fluorochrome staining and flow cytometry were conducted to determine apoptosis of GES-1cells. Spectrophotometry was performed to determine release of lactate dehydrogenate (LDH). Protein expression of Bcl-2, Bax, Akt, and glycogen synthase kinase (GSK)-3β was determined by western blotting. Expression of vanilloid receptor subtype 1 (VR1), Akt and GSK-3β was observed by immunocytochemistry. RESULTS: Compared with the H/R group, cell viability of the GH group was significantly increased in a dosedependent manner (55.9% ± 10.0% vs 69.6% ± 9.6%, 71.9% ± 17.4%, and 76.3% ± 13.3%). Compared with the H/R group, the percentage of apoptotic cells in the GH group significantly decreased (12.38% ± 1.51% vs 6.88% ± 0.87%). Compared with the GH group, the percentage of apoptotic cells in the D + GH group, C + GH group and L + GH groups significantly increased (11.70% ± 0.88%, 11.93% ± 0.96%, 10.20% ± 1.05% vs 6.88% ± 0.87%). There were no significant differences in the percentage of apoptotic cells between the H/R and DM groups (12.38% ± 1.51% vs 13.00% ± 1.13%). There was a significant decrease in LDH release following ghrelin postconditioning compared with the H/R group (561.58 ± 64.01 U/L vs 1062.45 ± 105.29 U/L). There was a significant increase in LDH release in the D + GH, C + GH and L + GH groups compared with the GH group (816.89 ± 94.87 U/L, 870.95 ± 64.06 U/L, 838.62 ± 118.45 U/L vs 561.58 ± 64.01 U/L). There were no significant differences in LDH release between the H/R and DM groups (1062.45 ± 105.29 U/L vs 1017.65 ± 68.90 U/L). Compared with the H/R group, expression of Bcl-2 and Akt increased in the GH group, whereas expression of Bax and GSK3β decreased. Compared with the GH group, expression of Bcl-2 decreased and Bax increased in the D + GH, C + GH and L + GH groups, and Akt decreased and GSK-3β increased in the L + GH group. The H/R group also upregulated expression of VR1 and GSK-3β and downregulated Akt. The number of VR1-positive and Akt-positive cells in the GH group significantly increased, whereas the number of GSK-3β-positive cells significantly decreased. These effects of ghrelin were reversed by capsazepine and LY294002.CONCLUSION: Ghrelin postconditioning protected against H/R-induced injury in human gastric epithelial cells, which indicated that this protection might be associated with GHS-R, VR1 and the PI3K/Akt signaling pathway.     

Connective tissue growth factor is overexpressed in human hepatocellular carcinoma and promotes cell invasion and growth

AIM: To determine the expression characteristics of connective tissue growth factor (CTGF/CCN2) in human hepatocellular carcinoma (HCC) in histology and to elucidate the roles of CCN2 on hepatoma cell cycle progression and metastasis in vitro.METHODS: Liver samples from 36 patients (who underwent hepatic resection for the first HCC between 2006 and 2011) and 6 normal individuals were examined for transforming growth factor β1 (TGF-β1) or CCN2 mRNA by in situ hybridization. Computer image analysis was performed to measure integrated optimal density of CCN2 mRNA-positive cells in carcinoma foci and the surrounding stroma. Fibroblast-specific protein-1 (FSP-1) and E-cadherin were examined to evaluate the process of epithelial to mesenchymal transition, α-smooth muscle actin and FSP-1 were detected to identify hepatic stellate cells, and CD34 was measured to evaluate the extent of vascularization in liver tissues by immunohistochemical staining. CCN2 was assessed for its stimulation of HepG2 cell migration and invasion using commercial kits while flow cytometry was used to determine CCN2 effects on HepG2 cell-cycle.RESULTS: In situ hybridization analysis showed that TGF-β1 mRNA was mainly detected in connective tissues and vasculature around carcinoma foci. In comparison to normal controls, CCN2 mRNA was enhanced 1.9-fold in carcinoma foci (12.36 ± 6.08 vs 6.42 ± 2.35) or 9.4-fold in the surrounding stroma (60.27 ± 28.71 vs 6.42 ± 2.35), with concomitant expression of CCN2 and TGF-β1 mRNA in those areas. Epithelial-mesenchymal transition phenotype related with CCN2 was detected in 12/36 (33.3%) of HCC liver samples at the edges between carcinoma foci and vasculature. Incubation of HepG2 cells with CCN2 (100 ng/mL) resulted in more of the cells transitioning into S phase (23.85 ± 2.35 vs 10.94 ± 0.23), and induced a significant migratory (4.0-fold) and invasive (5.7-fold) effect. TGF-β1-induced cell invasion was abrogated by a neutralizing CCN2 antibody showing that CCN2 is a downstream mediator of TGF-β1-induced hepatoma cell invasion.CONCLUSION: These data support a role for CCN2 in the growth and metastasis of HCC and highlight CCN2 as a potential novel therapeutic target.     

香芹酚对肝细胞癌HepG2细胞凋亡的诱导作用及其分子机制

目的:探讨香芹酚(carvacrol,CV)对人肝癌细胞(HepG2)的抗癌作用及其分子机制.方法:予以不同浓度的香芹酚(0.00、0.05、0.10、0.20、0.40 mmol/L)处理肝癌细胞HepG2后,采用四甲基偶氮唑蓝(MTT)比色法检测细胞活力;Hoechst33258染色法及流式细胞仪(FCM)技术检测...