BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the...BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.展开更多
Tanshinone IIA (Tan-IIA) is extracted from Dan-Shen. Tan-IIA could inhibit human pancreatic cancer BxPC-3 cells through decreasing TCTP, Mcl-1 and Bcl-xl expression in vitro. Our previous study showed that Tan-IIA can...Tanshinone IIA (Tan-IIA) is extracted from Dan-Shen. Tan-IIA could inhibit human pancreatic cancer BxPC-3 cells through decreasing TCTP, Mcl-1 and Bcl-xl expression in vitro. Our previous study showed that Tan-IIA can inhibit hepatocellular carcinoma hep-J5 cells and human breast cancer BT-20 cells through inducing endoplasmic reticulum (ER) stress. In the present study, we investigated the ER stress related protein expressions in human pancreatic cancer BxPC3 cells were treated with Tan-IIA. The ER stress related protein expressions in human pancreatic cancer BxPC-3 cells were evaluated by western blotting. The results showed that Tan-IIA can increase the protein expressions of PERK, ATF6, Caspase-12 and CHOP, but decrease Bip, PDI, Calnexin, Calreticulin and Bcl-2 expression. These findings indicated that Tan-IIA can inhibit human pancreatic cancer BxPC-3 cells by inducing ER stress to induce apoptosis.展开更多
AIM: To investigate the role of pancreatic stellate cells (PSCs) and galectin-3 (GAL-3) in the proliferation and infiltration of pancreatic cancer cell line SW1990. METHODS: Human pancreatic cancer cell line SW1990 an...AIM: To investigate the role of pancreatic stellate cells (PSCs) and galectin-3 (GAL-3) in the proliferation and infiltration of pancreatic cancer cell line SW1990. METHODS: Human pancreatic cancer cell line SW1990 and PSCs were cultured in vitro . Supernatant fluid of cultured PSCs and SW1990 cells was collected. Expression of GAL-3 in SW1990 cells and PSCs was detected by ELISA, RT-PCR and Western blotting. Proliferation of cultured PSCs and SW1990 cells was measured by 3-(4, 5-methylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Infiltration of SW1990 cells was detected by a cell infiltration kit. RESULTS: SW1990 cells expressed GAL-3 and this was up-regulated by the supernatant fluid of cultured PSCs. PSCs did not express GAL-3. SW1990 cells stimulated proliferation of PSCs via GAL-3. GAL-3 antibody inhibited SW1990 cell proliferation, while the supernatant fluid of PSCs stimulated proliferation of SW1990 cells through interaction with GAL-3 protein. The supernatant fluid of PSCs enhanced the invasiveness of SW1990 cells through interaction with GAL-3. CONCLUSION: GAL-3 and PSCs were involved in the proliferation and infiltration process of pancreatic cancer cells.展开更多
AIM: To clarify the effects of epigallocatechin-3-gallate (EGCG) on the platelet-derived growth factor (PDGF)-BBinduced proliferation and migration of pancreatic stellate cells (PSCs).METHODS: PSCs were isolated from ...AIM: To clarify the effects of epigallocatechin-3-gallate (EGCG) on the platelet-derived growth factor (PDGF)-BBinduced proliferation and migration of pancreatic stellate cells (PSCs).METHODS: PSCs were isolated from rat pancreas tissue and used in their culture-activated, myofibroblast-like phenotype. Cell proliferation was assessed by measuring the incorporation of 5-bromo-2'-deoxyuridine. Cell migration was assessed using modified Boyden chambers. CyclinD1, p21waf1, and p27kip1 expression and phosphorylation of PDGF β-receptor, extracellular signal-regulated kinase, and Akt were examined by Western blotting. Activation of phosphatidylinositol 3-kinase was examined by kinase assay using phosphatidylinositol as a substrate. Cell cycle was assessed by flow cytometry after staining with propidium iodide. RESULTS: EGCG at non-cytotoxic concentrations inhibited PDGF-induced proliferation and migration. This effect was associated with the inhibition of cell cycle progression beyondthe G1 phase, decreased cyclin D1 and increased p27Kip1 expression. EGCG inhibited tyrosine phosphorylation of PDGF β-receptor and downstream activation of extracellular signal-regulated kinase and phosphatidylinositol 3-kinase/ Akt pathways.CONCLUSION: EGCG inhibited PDGF-BB-induced proliferation and migration of PSCs through the inhibrdon of PDGF-mediated signaling pathways.展开更多
Whether M3 cholinergic receptor signal transduction pathway is involved in regulation of the activation of NF-κB and the expression of chemokine MOB-1, MCP-1genes in pancreatic acinar cells was investigated. Rat panc...Whether M3 cholinergic receptor signal transduction pathway is involved in regulation of the activation of NF-κB and the expression of chemokine MOB-1, MCP-1genes in pancreatic acinar cells was investigated. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, atropine and PDTC in vitro. The MOB-1 and MCP-1 mRNA expression was detected by using RT-PCR. The activation of NF-κB was monitored by using electrophoretic mobility shift assay. The results showed that as compared with control group, M3 cholinergic receptor agonist (10 -3 mol/L, 10 -4 mol/L carbachol) could induce a concentration-dependent and time-dependent increase in the expression of MOB-1, MCP-1 mRNA in pancreatic acinar cells. After treatment with 10 -3 mol/L carbachol for 2 h, the expression of MOB-1, MCP-1 mRNA was strongest. The activity of NF-κB in pancreatic acinar cells was significantly increased (P<0.01) after treated with M3 cholinergic receptor agonist (10 -3 mol/L carbachol) in vitro for 30 min. Either M3 cholinergic receptor antagonist (10 -5 mol/L atropine) or NF-κB inhibitor (10 -2 mol/L PDTC) could obviously inhibit the activation of NF-κB and the chemokine MOB-1, MCP-1 mRNA expression induced by carbachol (P<0.05). This inhibitory effect was significantly increased by atropine plus PDTC (P<0.01). The results of these studies indicated that M3 cholinergic receptor signal transduction pathway was likely involved in regulation of the expression of chemokine MOB-1 and MCP-1genes in pancreatic acinar cells in vitro through the activation of NF-κB.展开更多
Objective To investigate the role of pancreatic stellate cells (PSCs) and galectin-3 (GAL-3) on the proliferation and infiltration of pancreatic cancer cell line SW1990. Methods Human pancreatic cancer cell line SW199...Objective To investigate the role of pancreatic stellate cells (PSCs) and galectin-3 (GAL-3) on the proliferation and infiltration of pancreatic cancer cell line SW1990. Methods Human pancreatic cancer cell line SW1990 and PSCs were cultured in vitro. Supernatant of cultured PSCs and SW1990 cells was collected. Expressions of GAL-3 in SW1990 cells and PSCs were detected by ELISA, RT-PCR and Western blot. The proliferation of those cultured PSCs and SW1990 cells were measured by MTT assay and flowcytometry. Infiltration of SW1990 cells was detected by cell infiltration kit. Results SW1990 cells expressed GAL-3 and the expression was up-regulated by the supernatant fluid of cultured PSCs. PSCs did not express GAL-3. SW1990 cells could stimulate the proliferation of PSCs via GAL-3. GAL-3 antibody could inhibit SW1990 cells proliferation and infiltration, which indicated that supernatant of PSCs might stimulate the proliferation of SW1990 cells through the interaction with GAL-3 protein. The supernatant fluid of PSCs could enhance the invasiveness of SW1990 cells through the interaction with GAL-3. Conclusion GAL-3 and PSCs was involved in the proliferation and infiltration process of pancreatic cancer.展开更多
AIM:To investigate the effects of ginsenoside Rh2 on the human pancreatic cancer cell line Bxpc-3.METHODS:The human pancreatic cancer cell line Bxpc-3 was cultured in vitro and treated with or without ginsenoside Rh2....AIM:To investigate the effects of ginsenoside Rh2 on the human pancreatic cancer cell line Bxpc-3.METHODS:The human pancreatic cancer cell line Bxpc-3 was cultured in vitro and treated with or without ginsenoside Rh2.Growth rates for Bxpc-3 cells were assessed by methyl thiazolyl tetrazolium(MTT) and colony formation assays.Cell cycle changes were analyzed by flow cytometry.Apoptosis was measured by flow cytometry and Hoechst 33258 fluorescence staining.A scratch assay and a Matrigel invasion assay were used to detect cell migration and invasion.Expression of Bax,Bcl-2,survivin,cyclin D1,matrix metalloproteinase(MMP)-2,MMP-9,cleaved caspase-3,caspase-8,and caspase-9 mRNA were determined by reverse transcriptase-polymerase chain reaction(RT-PCR).Bax,Bcl-2,survivin,cyclin D1,cleaved caspase-3,caspase-8 and caspase-9 protein levels were examined by western blotting.Expression of MMP-2 and MMP-9 proteins in culture supernatants were determined by enzymelinked immunosorbent assay(ELISA).RESULTS:Rh2 significantly inhibited Bxpc-3 cell proliferation in a dose-and time-dependent manner,as evaluated by the MTT(P < 0.05) and colony formation assays(P < 0.05).Compared to the control group,Rh2 significantly increased the percentage of Bxpc-3 cells in the G 0 /G 1 phase from 43.32% ± 2.17% to 71.32% ± 1.16%,which was accompanied by a decrease in S phase(from 50.86% ± 1.29% to 28.48% ± 1.18%) and G 2 /M phase(from 5.81% ± 1.19% to 0.20% ± 0.05%) in a dose-dependent manner(P < 0.05),suggesting that Rh2 arrested cell cycle progression at the G 0 /G 1 phase,as measured by flow cytometry.Compared to the control group,cells treated with Rh2 showed significantly higher apoptosis ratios in a dosedependent manner(percentage of early apoptotic cells:from 5.29% ± 2.28% to 38.90% ± 3.42%(F = 56.20,P < 0.05);percentage of late apoptotic cells:from 4.58% ± 1.42% to 36.32% ± 2.73%(F = 86.70,P < 0.05).Rh2 inhibited Bxpc-3 cell migration and invasion,as detected by scratch wound healing assay and Matrigel invasion assay [percentages of scratch wound healing for 12 h,24 h and 48 h(control vs experimental group):37.3% ± 4.8%vs 18.30% ± 1.65%,58.7% ± 3.5% vs 38.00% ± 4.09% and 93.83% ± 4.65% vs 65.50% ± 4.09%,respectively;t = 6.489,t = 6.656 and t = 7.926,respectively,P < 0.05;the number of cells invading at various concentrations(0 μmol/L,35 μmol/L,45 μmol/L and 55 μmol/L):81.10 ± 9.55,46.40 ± 6.95,24.70 ± 6.88 and 8.70 ± 3.34,respectively(F = 502.713,P < 0.05)].RT-PCR,western blotting or ELISA showed that mRNA and protein expression of Bax,cleaved caspase-3 and caspase-9 were upregulated(P < 0.05),while mRNA and protein expression of Bcl-2,survivin,cyclin D1,MMP-2 and MMP-9 were downregulated(P < 0.05).CONCLUSION:Ginsenoside Rh2 inhibits proliferation,migration and invasion and induces apoptosis of the human pancreatic cancer cell line Bxpc-3.展开更多
AIM To study the molecular effects of three different D-vitamins, vitamin D2, vitamin D3 and calcipotriol, in pancreatic stellate cells(PSCs).METHODS Quiescent PSCs were isolated from mouse pancreas and activated in v...AIM To study the molecular effects of three different D-vitamins, vitamin D2, vitamin D3 and calcipotriol, in pancreatic stellate cells(PSCs).METHODS Quiescent PSCs were isolated from mouse pancreas and activated in vitro by seeding on plastic surfaces. The cells were exposed to D-vitamins as primary cultures(early-activated PSCs) and upon re-culturing(fullyactivated cells). Exhibition of vitamin A-containing lipid droplets was visualized by oil-red staining. Expression of α-smooth muscle actin(α-SMA), a marker of PSC activation, was monitored by immunofluorescence and immunoblot analysis. The rate of DNA synthesis was quantified by 5-bromo-2'-deoxyuridine(Brd U) incorporation assays. Real-time PCR was employed to monitor gene expression, and protein levels of interleukin-6(IL-6) were measured by ELISA. Uptake of proline was determined using 18 F-proline.RESULTS Sustained culture of originally quiescent PSCs inducedcell proliferation, loss of lipid droplets and exhibition of stress fibers, indicating cell activation. When added to PSCs in primary culture, all three D-vitamins diminished expression of α-SMA(to 32%-39% of the level of control cells; P < 0.05) and increased the storage of lipids(scores from 1.97-2.15 on a scale from 0-3; controls: 1.49; P < 0.05). No such effects were observed when D-vitamins were added to fully-activated cells, while incorporation of Brd U remained unaffected under both experimental conditions. Treatment of re-cultured PSCs with D-vitamins was associated with lower expression of IL-6(-42% to-49%; P < 0.05; also confirmed at the protein level) and increased expression of the vitamin D receptor gene(209%-321% vs controls; P < 0.05). There was no effect of D-vitamins on the expression of transforming growth factor-β1 and collagen type 1(chain α1). The lowest uptake of proline, a main component of collagen, was observed in calcipotriol-treated PSCs.CONCLUSION The three D-vitamins inhibit, with similar efficiencies, activation of PSCs in vitro, but cannot reverse the phenotype once the cells are fully activated.展开更多
This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cell...This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cells(DCs) pulsed with tumor cell lysate in the mice bearing pancreatic adenocarcinoma.The models of pancreatic adenocarcinoma were established in C57BL/6 mice by subcutaneous injection of Pan02 cells.Eight mice which were subcutaneously injected with PBS served as control.The expression of IDO was determined in tumor draining lymph nodes(TDLNs) and spleens of the murine pancreatic adenocarcinoma models.The prevalence of Tregs was measured in the TDLNs and spleens before and after 1-MT administration.The dendritic cells were pulsed with tumor cell lysate for preparing DC vaccine.The DC vaccine,as a single agent or in combination with 1-MT,was administered to pancreatic adenocarcinoma mice.The anti-tumor efficacy was determined after different treatments by regular observation of tumor size.The results showed that the levels of IDO mRNA and protein in tumor-bearing mice were significantly higher than those in the normal control mice.The percentage of Tregs in the spleen and TDLNs was also higer in tumor-bearing mice than in normal control mice(P<0.05).Foxp3 expression was significantly lower in the TDLNs and spleens of tumor-bearing mice administrated with 1-MT than that in normal control mice.Furthemore,in the mice that were administered 1-MT plus DC vaccine,the tumor was increased more slowly than in mice treated with DC vaccine or 1-MT alone,or PBS on day 36(P<0.01).Our results indicated that 1-MT may enhance anti-tumor efficacy of dendritic cells pulsed with tumor cell lysate by downregulating the percentage of Tregs.展开更多
AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles pe...AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles per liter of caerulein(Cae)was administrated to induce the apoptosis of AR42 J cells and the apoptosis rate was detected by flow cytometry analysis. An amylase assay kit was used to measure the amylase expression level in the supernatant. Quantitative real-time PCR(qRT-PCR)was adopted to measure miR-22 expression. We used online tools to predict the potential transcription promoter of miR-22 and the binding sites, which was further identified by using luciferase reporter analysis,chromatin immunoprecipitation(ChIP) and ChIPqP CR assays. Then, a mimic of miR-22, Nr3 c1 plasmid encoding the glucocorticoid receptor(GR), and siNr3 c1 were used to transfect AR42 J cells, respectively.The mRNA expression of miR-22, Nr3 c1, and Erb-b2 receptor tyrosine kinase 3(ErbB3) was confirmed by qRT-PCR and the apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of ErbB3, GR, PI3 k, PI3 kp85α, Akt, p-Akt, Bad, Bax, Bcl-xl, Bcl-2, and cleaved caspase3.RESULTS After inducing apoptosis of AR42 J cells in vitro, the expression of miR-22 was significantly increased by2.20 ± 0.26 and 4.19 ± 0.54 times, respectively, at3 h and 6 h in comparison with the control group.As revealed by qRT-PCR assay, the expression of miR-22 was 78.25 ± 6.61 times higher in the miR-22 mimic group relative to the miRNA control group,accompanied with an obviously increased acinar cell apoptosis rate(32.53 ± 1.15 vs 18.07 ± 0.89, P =0.0006). The upregulation of miR-22 could suppress its target gene, ErbB3, and the phosphorylation of PI3 k and Akt. Furthermore, we predicted the potential transcription promoter of miR-22 and the binding sites using online tools. Luciferase reporter analysis and sitedirected mutagenesis indicated that the binding site(GACAGCCATGTACA) of the GR, which is encoded by the Nr3 c1 gene. Downregulation of the expression of GR could upregulate the expression of miR-22, which further promoted the apoptosis of AR42 J cells.CONCLUSION GR transcriptionally represses the expression of miR-22,which further promotes the apoptosis of pancreatic acinar cells by downregulating the downstream signaling pathway.展开更多
Sustained heavy ethanol drinking is a common problem globally and ethanol is one of the most abused drugs among individuals of different socio-economic status including the HIV-infected patients on antiretroviral drug...Sustained heavy ethanol drinking is a common problem globally and ethanol is one of the most abused drugs among individuals of different socio-economic status including the HIV-infected patients on antiretroviral drugs. Ethanol is reward drug and a CNS depressant especially at high doses. The study determined the effect of sustained heavy ethanol drinking by HIV-infected patients on d4T/3TC/NVP regimen on CD4+ cell counts in Uganda using WHO AUDIT tool and chronic alcohol-use biomarkers. A case control study using repeated measures design with serial measurements model was used. The patients on stavudine (d4T) 30 mg, lamivudine (3TC) 150 mg and nevirapine (NVP) 200 mg and chronic alcohol use were recruited. A total of 41 patients (20 in alcohol group and 21 in control group) were screened for chronic alcohol use by WHO AUDIT tool and chronic alcohol use biomarkers. They were followed up for 9 months with blood sampling done at 3 months intervals. CD4+ cell count was determined using Facscalibur Flow Cytometer system. Results were then sorted by alcohol-use biomarkers (GGT, MCV and AST/ ALT ratio). Data were analysed using SAS 2003 version 9.1 statistical package with repeated measures fixed model and the means were compared using student t-test. The mean CD4+ cell counts in all the groups were lower than the reference ranges at baseline and gradually increased at 3, 6 and 9 months of follow-up. The mean CD4+ cell counts were higher in the control group as compared to the chronic alcohol use group in both WHO AUDIT tool group and chronic alcohol-use biomarkers group though there was no significant difference (p > 0.05). Chronic alcohol use slightly lowers CD4+ cell count in HIV-infected patients on d4T/3TC/NVP treatment regimen.展开更多
CYP3A5 is a cytochrome P450(CYP)enzyme that metabolizes drugs and contributes to drug resistance in cancer.However,it remains unclear whether CYP3A5 directly influences cancer progression.In this report,we demonstrate...CYP3A5 is a cytochrome P450(CYP)enzyme that metabolizes drugs and contributes to drug resistance in cancer.However,it remains unclear whether CYP3A5 directly influences cancer progression.In this report,we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma.Multi-omics analysis showed that CYP3A5 knockdown re-sults in a decrease in various glucose-related metabolites through its effect on glucose trans-port.A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP,a negative regulator of GLUT1.Notably,CYP3A5-generated reactive oxygen species were proved to be responsible for atten-uating the AKT-4EBP1-TXNIP signaling pathway.CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer.Taken together,our results,for the first time,reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.展开更多
Conophylline, is a bis (indole) alkaloid consisting of two pentacyclic aspidosperma skeletons, isolated from Tabernaemontana divaricata, which has been found to induce β-cell differentiation in rat pancreatic acina...Conophylline, is a bis (indole) alkaloid consisting of two pentacyclic aspidosperma skeletons, isolated from Tabernaemontana divaricata, which has been found to induce β-cell differentiation in rat pancreatic acinar carcinoma cells and in cultured rat pancreatic tissue. However, the precise role of conophylline in the growth and survival of immortalized pancreatic mesenchymal stem cells (iPMSCs) derived from fetal porcine pancreas were not understood at present. To determine whether this molecule is involved in controlling the proliferation of iPMSCs, we examined the effects of conophylline on iPMSCs. We found that conophylline can robustly stimulate iPMSCs proliferation, even promote their potential differentiation into islet-like clusters analyzed by cell counting, morphology, RT-PCR and real-time PCR, Western blotting, glucose-stimulated insulin release and insulin content analysis. The effects of conophylline were inhibited by LY294002, which is the inhibitor of the PI3K pathway. These results suggest that conophylline plays a key role in the regulation of cell mass proliferation, maintenance of the undifferentiated state of iPMSCs and also promotes iPMSCs differentiated into insulin-producing cells.展开更多
A large body of experimental and clinical data supports the notion that inflammation in acute pancreatitis has a crucial role in the pathogenesis of local and systemic damage and is a major determinant of clinical sev...A large body of experimental and clinical data supports the notion that inflammation in acute pancreatitis has a crucial role in the pathogenesis of local and systemic damage and is a major determinant of clinical severity.Thus,research has recently focused on molecules that can regulate the inflammatory processes,such as phosphoinositide 3-kinases(PI3Ks),a family of lipid and protein kinases involved in intracellular signal transduction.Studies using genetic ablation or pharmacologic inhibitors of different PI3 K isoforms,in particular the class I PI3Kδ and PI3Kγ,have contributed to a greater understanding of the roles of these kinases in the modulation of inflammatory and immune responses.Recent data suggest that PI3 Ks are also involved in the pathogenesis of acute pancreatitis.Activation of the PI3K signaling pathway,and in particular of the class IB PI3Kγ isoform,has a significant role in those events which are necessary for the initiation of acute pancreatic injury,namely calcium signaling alteration,trypsinogen activation,and nuclear factor-κB transcription.Moreover,PI3Kγ is instrumental in modulating acinar cell apoptosis,and regulating local neutrophil infiltration and systemic inflammatory responses during the course of experimental acute pancreatitis.The availability of PI3 K inhibitors selective for specific isoforms may provide new valuable therapeutic strategies to improve the clinical course of this disease.This article presents a brief summary of PI3 K structure and function,and highlights recent advances that implicate PI3 Ks in the pathogenesis of acute pancreatitis.展开更多
基金supported by grants from the Natural Science Foundation of Jiangsu Province,China (No. BK2006241)the Foundation for Talents in Six Fields of Jiangsu Province (No. 07-B-038)
文摘BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.
文摘Tanshinone IIA (Tan-IIA) is extracted from Dan-Shen. Tan-IIA could inhibit human pancreatic cancer BxPC-3 cells through decreasing TCTP, Mcl-1 and Bcl-xl expression in vitro. Our previous study showed that Tan-IIA can inhibit hepatocellular carcinoma hep-J5 cells and human breast cancer BT-20 cells through inducing endoplasmic reticulum (ER) stress. In the present study, we investigated the ER stress related protein expressions in human pancreatic cancer BxPC3 cells were treated with Tan-IIA. The ER stress related protein expressions in human pancreatic cancer BxPC-3 cells were evaluated by western blotting. The results showed that Tan-IIA can increase the protein expressions of PERK, ATF6, Caspase-12 and CHOP, but decrease Bip, PDI, Calnexin, Calreticulin and Bcl-2 expression. These findings indicated that Tan-IIA can inhibit human pancreatic cancer BxPC-3 cells by inducing ER stress to induce apoptosis.
文摘AIM: To investigate the role of pancreatic stellate cells (PSCs) and galectin-3 (GAL-3) in the proliferation and infiltration of pancreatic cancer cell line SW1990. METHODS: Human pancreatic cancer cell line SW1990 and PSCs were cultured in vitro . Supernatant fluid of cultured PSCs and SW1990 cells was collected. Expression of GAL-3 in SW1990 cells and PSCs was detected by ELISA, RT-PCR and Western blotting. Proliferation of cultured PSCs and SW1990 cells was measured by 3-(4, 5-methylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Infiltration of SW1990 cells was detected by a cell infiltration kit. RESULTS: SW1990 cells expressed GAL-3 and this was up-regulated by the supernatant fluid of cultured PSCs. PSCs did not express GAL-3. SW1990 cells stimulated proliferation of PSCs via GAL-3. GAL-3 antibody inhibited SW1990 cell proliferation, while the supernatant fluid of PSCs stimulated proliferation of SW1990 cells through interaction with GAL-3 protein. The supernatant fluid of PSCs enhanced the invasiveness of SW1990 cells through interaction with GAL-3. CONCLUSION: GAL-3 and PSCs were involved in the proliferation and infiltration process of pancreatic cancer cells.
基金Supported by the Grant-in-Aid for Encouragement of Young Scientists from Japan Society for the Promotion of Science, No. 16590572 Pancreas Research Foundation of Japan, No. 01-01 the Kanae Foundation for Life and Socio-Medical Science
文摘AIM: To clarify the effects of epigallocatechin-3-gallate (EGCG) on the platelet-derived growth factor (PDGF)-BBinduced proliferation and migration of pancreatic stellate cells (PSCs).METHODS: PSCs were isolated from rat pancreas tissue and used in their culture-activated, myofibroblast-like phenotype. Cell proliferation was assessed by measuring the incorporation of 5-bromo-2'-deoxyuridine. Cell migration was assessed using modified Boyden chambers. CyclinD1, p21waf1, and p27kip1 expression and phosphorylation of PDGF β-receptor, extracellular signal-regulated kinase, and Akt were examined by Western blotting. Activation of phosphatidylinositol 3-kinase was examined by kinase assay using phosphatidylinositol as a substrate. Cell cycle was assessed by flow cytometry after staining with propidium iodide. RESULTS: EGCG at non-cytotoxic concentrations inhibited PDGF-induced proliferation and migration. This effect was associated with the inhibition of cell cycle progression beyondthe G1 phase, decreased cyclin D1 and increased p27Kip1 expression. EGCG inhibited tyrosine phosphorylation of PDGF β-receptor and downstream activation of extracellular signal-regulated kinase and phosphatidylinositol 3-kinase/ Akt pathways.CONCLUSION: EGCG inhibited PDGF-BB-induced proliferation and migration of PSCs through the inhibrdon of PDGF-mediated signaling pathways.
文摘Whether M3 cholinergic receptor signal transduction pathway is involved in regulation of the activation of NF-κB and the expression of chemokine MOB-1, MCP-1genes in pancreatic acinar cells was investigated. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, atropine and PDTC in vitro. The MOB-1 and MCP-1 mRNA expression was detected by using RT-PCR. The activation of NF-κB was monitored by using electrophoretic mobility shift assay. The results showed that as compared with control group, M3 cholinergic receptor agonist (10 -3 mol/L, 10 -4 mol/L carbachol) could induce a concentration-dependent and time-dependent increase in the expression of MOB-1, MCP-1 mRNA in pancreatic acinar cells. After treatment with 10 -3 mol/L carbachol for 2 h, the expression of MOB-1, MCP-1 mRNA was strongest. The activity of NF-κB in pancreatic acinar cells was significantly increased (P<0.01) after treated with M3 cholinergic receptor agonist (10 -3 mol/L carbachol) in vitro for 30 min. Either M3 cholinergic receptor antagonist (10 -5 mol/L atropine) or NF-κB inhibitor (10 -2 mol/L PDTC) could obviously inhibit the activation of NF-κB and the chemokine MOB-1, MCP-1 mRNA expression induced by carbachol (P<0.05). This inhibitory effect was significantly increased by atropine plus PDTC (P<0.01). The results of these studies indicated that M3 cholinergic receptor signal transduction pathway was likely involved in regulation of the expression of chemokine MOB-1 and MCP-1genes in pancreatic acinar cells in vitro through the activation of NF-κB.
文摘Objective To investigate the role of pancreatic stellate cells (PSCs) and galectin-3 (GAL-3) on the proliferation and infiltration of pancreatic cancer cell line SW1990. Methods Human pancreatic cancer cell line SW1990 and PSCs were cultured in vitro. Supernatant of cultured PSCs and SW1990 cells was collected. Expressions of GAL-3 in SW1990 cells and PSCs were detected by ELISA, RT-PCR and Western blot. The proliferation of those cultured PSCs and SW1990 cells were measured by MTT assay and flowcytometry. Infiltration of SW1990 cells was detected by cell infiltration kit. Results SW1990 cells expressed GAL-3 and the expression was up-regulated by the supernatant fluid of cultured PSCs. PSCs did not express GAL-3. SW1990 cells could stimulate the proliferation of PSCs via GAL-3. GAL-3 antibody could inhibit SW1990 cells proliferation and infiltration, which indicated that supernatant of PSCs might stimulate the proliferation of SW1990 cells through the interaction with GAL-3 protein. The supernatant fluid of PSCs could enhance the invasiveness of SW1990 cells through the interaction with GAL-3. Conclusion GAL-3 and PSCs was involved in the proliferation and infiltration process of pancreatic cancer.
基金Supported by National Natural Science Foundation of China,No. 30700252Health Department Project of Guangxi,No.Z2012104Education Department Project of Guangxi,No.201204LX048
文摘AIM:To investigate the effects of ginsenoside Rh2 on the human pancreatic cancer cell line Bxpc-3.METHODS:The human pancreatic cancer cell line Bxpc-3 was cultured in vitro and treated with or without ginsenoside Rh2.Growth rates for Bxpc-3 cells were assessed by methyl thiazolyl tetrazolium(MTT) and colony formation assays.Cell cycle changes were analyzed by flow cytometry.Apoptosis was measured by flow cytometry and Hoechst 33258 fluorescence staining.A scratch assay and a Matrigel invasion assay were used to detect cell migration and invasion.Expression of Bax,Bcl-2,survivin,cyclin D1,matrix metalloproteinase(MMP)-2,MMP-9,cleaved caspase-3,caspase-8,and caspase-9 mRNA were determined by reverse transcriptase-polymerase chain reaction(RT-PCR).Bax,Bcl-2,survivin,cyclin D1,cleaved caspase-3,caspase-8 and caspase-9 protein levels were examined by western blotting.Expression of MMP-2 and MMP-9 proteins in culture supernatants were determined by enzymelinked immunosorbent assay(ELISA).RESULTS:Rh2 significantly inhibited Bxpc-3 cell proliferation in a dose-and time-dependent manner,as evaluated by the MTT(P < 0.05) and colony formation assays(P < 0.05).Compared to the control group,Rh2 significantly increased the percentage of Bxpc-3 cells in the G 0 /G 1 phase from 43.32% ± 2.17% to 71.32% ± 1.16%,which was accompanied by a decrease in S phase(from 50.86% ± 1.29% to 28.48% ± 1.18%) and G 2 /M phase(from 5.81% ± 1.19% to 0.20% ± 0.05%) in a dose-dependent manner(P < 0.05),suggesting that Rh2 arrested cell cycle progression at the G 0 /G 1 phase,as measured by flow cytometry.Compared to the control group,cells treated with Rh2 showed significantly higher apoptosis ratios in a dosedependent manner(percentage of early apoptotic cells:from 5.29% ± 2.28% to 38.90% ± 3.42%(F = 56.20,P < 0.05);percentage of late apoptotic cells:from 4.58% ± 1.42% to 36.32% ± 2.73%(F = 86.70,P < 0.05).Rh2 inhibited Bxpc-3 cell migration and invasion,as detected by scratch wound healing assay and Matrigel invasion assay [percentages of scratch wound healing for 12 h,24 h and 48 h(control vs experimental group):37.3% ± 4.8%vs 18.30% ± 1.65%,58.7% ± 3.5% vs 38.00% ± 4.09% and 93.83% ± 4.65% vs 65.50% ± 4.09%,respectively;t = 6.489,t = 6.656 and t = 7.926,respectively,P < 0.05;the number of cells invading at various concentrations(0 μmol/L,35 μmol/L,45 μmol/L and 55 μmol/L):81.10 ± 9.55,46.40 ± 6.95,24.70 ± 6.88 and 8.70 ± 3.34,respectively(F = 502.713,P < 0.05)].RT-PCR,western blotting or ELISA showed that mRNA and protein expression of Bax,cleaved caspase-3 and caspase-9 were upregulated(P < 0.05),while mRNA and protein expression of Bcl-2,survivin,cyclin D1,MMP-2 and MMP-9 were downregulated(P < 0.05).CONCLUSION:Ginsenoside Rh2 inhibits proliferation,migration and invasion and induces apoptosis of the human pancreatic cancer cell line Bxpc-3.
基金Supported by FORUN program of the Rostock University Medical Center
文摘AIM To study the molecular effects of three different D-vitamins, vitamin D2, vitamin D3 and calcipotriol, in pancreatic stellate cells(PSCs).METHODS Quiescent PSCs were isolated from mouse pancreas and activated in vitro by seeding on plastic surfaces. The cells were exposed to D-vitamins as primary cultures(early-activated PSCs) and upon re-culturing(fullyactivated cells). Exhibition of vitamin A-containing lipid droplets was visualized by oil-red staining. Expression of α-smooth muscle actin(α-SMA), a marker of PSC activation, was monitored by immunofluorescence and immunoblot analysis. The rate of DNA synthesis was quantified by 5-bromo-2'-deoxyuridine(Brd U) incorporation assays. Real-time PCR was employed to monitor gene expression, and protein levels of interleukin-6(IL-6) were measured by ELISA. Uptake of proline was determined using 18 F-proline.RESULTS Sustained culture of originally quiescent PSCs inducedcell proliferation, loss of lipid droplets and exhibition of stress fibers, indicating cell activation. When added to PSCs in primary culture, all three D-vitamins diminished expression of α-SMA(to 32%-39% of the level of control cells; P < 0.05) and increased the storage of lipids(scores from 1.97-2.15 on a scale from 0-3; controls: 1.49; P < 0.05). No such effects were observed when D-vitamins were added to fully-activated cells, while incorporation of Brd U remained unaffected under both experimental conditions. Treatment of re-cultured PSCs with D-vitamins was associated with lower expression of IL-6(-42% to-49%; P < 0.05; also confirmed at the protein level) and increased expression of the vitamin D receptor gene(209%-321% vs controls; P < 0.05). There was no effect of D-vitamins on the expression of transforming growth factor-β1 and collagen type 1(chain α1). The lowest uptake of proline, a main component of collagen, was observed in calcipotriol-treated PSCs.CONCLUSION The three D-vitamins inhibit, with similar efficiencies, activation of PSCs in vitro, but cannot reverse the phenotype once the cells are fully activated.
文摘This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cells(DCs) pulsed with tumor cell lysate in the mice bearing pancreatic adenocarcinoma.The models of pancreatic adenocarcinoma were established in C57BL/6 mice by subcutaneous injection of Pan02 cells.Eight mice which were subcutaneously injected with PBS served as control.The expression of IDO was determined in tumor draining lymph nodes(TDLNs) and spleens of the murine pancreatic adenocarcinoma models.The prevalence of Tregs was measured in the TDLNs and spleens before and after 1-MT administration.The dendritic cells were pulsed with tumor cell lysate for preparing DC vaccine.The DC vaccine,as a single agent or in combination with 1-MT,was administered to pancreatic adenocarcinoma mice.The anti-tumor efficacy was determined after different treatments by regular observation of tumor size.The results showed that the levels of IDO mRNA and protein in tumor-bearing mice were significantly higher than those in the normal control mice.The percentage of Tregs in the spleen and TDLNs was also higer in tumor-bearing mice than in normal control mice(P<0.05).Foxp3 expression was significantly lower in the TDLNs and spleens of tumor-bearing mice administrated with 1-MT than that in normal control mice.Furthemore,in the mice that were administered 1-MT plus DC vaccine,the tumor was increased more slowly than in mice treated with DC vaccine or 1-MT alone,or PBS on day 36(P<0.01).Our results indicated that 1-MT may enhance anti-tumor efficacy of dendritic cells pulsed with tumor cell lysate by downregulating the percentage of Tregs.
基金National Natural Science Foundation of China,No.31671440
文摘AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles per liter of caerulein(Cae)was administrated to induce the apoptosis of AR42 J cells and the apoptosis rate was detected by flow cytometry analysis. An amylase assay kit was used to measure the amylase expression level in the supernatant. Quantitative real-time PCR(qRT-PCR)was adopted to measure miR-22 expression. We used online tools to predict the potential transcription promoter of miR-22 and the binding sites, which was further identified by using luciferase reporter analysis,chromatin immunoprecipitation(ChIP) and ChIPqP CR assays. Then, a mimic of miR-22, Nr3 c1 plasmid encoding the glucocorticoid receptor(GR), and siNr3 c1 were used to transfect AR42 J cells, respectively.The mRNA expression of miR-22, Nr3 c1, and Erb-b2 receptor tyrosine kinase 3(ErbB3) was confirmed by qRT-PCR and the apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of ErbB3, GR, PI3 k, PI3 kp85α, Akt, p-Akt, Bad, Bax, Bcl-xl, Bcl-2, and cleaved caspase3.RESULTS After inducing apoptosis of AR42 J cells in vitro, the expression of miR-22 was significantly increased by2.20 ± 0.26 and 4.19 ± 0.54 times, respectively, at3 h and 6 h in comparison with the control group.As revealed by qRT-PCR assay, the expression of miR-22 was 78.25 ± 6.61 times higher in the miR-22 mimic group relative to the miRNA control group,accompanied with an obviously increased acinar cell apoptosis rate(32.53 ± 1.15 vs 18.07 ± 0.89, P =0.0006). The upregulation of miR-22 could suppress its target gene, ErbB3, and the phosphorylation of PI3 k and Akt. Furthermore, we predicted the potential transcription promoter of miR-22 and the binding sites using online tools. Luciferase reporter analysis and sitedirected mutagenesis indicated that the binding site(GACAGCCATGTACA) of the GR, which is encoded by the Nr3 c1 gene. Downregulation of the expression of GR could upregulate the expression of miR-22, which further promoted the apoptosis of AR42 J cells.CONCLUSION GR transcriptionally represses the expression of miR-22,which further promotes the apoptosis of pancreatic acinar cells by downregulating the downstream signaling pathway.
文摘Sustained heavy ethanol drinking is a common problem globally and ethanol is one of the most abused drugs among individuals of different socio-economic status including the HIV-infected patients on antiretroviral drugs. Ethanol is reward drug and a CNS depressant especially at high doses. The study determined the effect of sustained heavy ethanol drinking by HIV-infected patients on d4T/3TC/NVP regimen on CD4+ cell counts in Uganda using WHO AUDIT tool and chronic alcohol-use biomarkers. A case control study using repeated measures design with serial measurements model was used. The patients on stavudine (d4T) 30 mg, lamivudine (3TC) 150 mg and nevirapine (NVP) 200 mg and chronic alcohol use were recruited. A total of 41 patients (20 in alcohol group and 21 in control group) were screened for chronic alcohol use by WHO AUDIT tool and chronic alcohol use biomarkers. They were followed up for 9 months with blood sampling done at 3 months intervals. CD4+ cell count was determined using Facscalibur Flow Cytometer system. Results were then sorted by alcohol-use biomarkers (GGT, MCV and AST/ ALT ratio). Data were analysed using SAS 2003 version 9.1 statistical package with repeated measures fixed model and the means were compared using student t-test. The mean CD4+ cell counts in all the groups were lower than the reference ranges at baseline and gradually increased at 3, 6 and 9 months of follow-up. The mean CD4+ cell counts were higher in the control group as compared to the chronic alcohol use group in both WHO AUDIT tool group and chronic alcohol-use biomarkers group though there was no significant difference (p > 0.05). Chronic alcohol use slightly lowers CD4+ cell count in HIV-infected patients on d4T/3TC/NVP treatment regimen.
基金supported by the National Institute of General Medical Sciences of the National Institutes of Health under award number R35GM118041.
文摘CYP3A5 is a cytochrome P450(CYP)enzyme that metabolizes drugs and contributes to drug resistance in cancer.However,it remains unclear whether CYP3A5 directly influences cancer progression.In this report,we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma.Multi-omics analysis showed that CYP3A5 knockdown re-sults in a decrease in various glucose-related metabolites through its effect on glucose trans-port.A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP,a negative regulator of GLUT1.Notably,CYP3A5-generated reactive oxygen species were proved to be responsible for atten-uating the AKT-4EBP1-TXNIP signaling pathway.CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer.Taken together,our results,for the first time,reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.
基金supported by the grants from the National Natural Science Foundation of China(31272518, 31101775, 30972097)the Doctoral Fund of Ministry of Education of China (20100204120020)+4 种基金the Program for New Century Excellent Talents of State Ministry of Education (NCET-09-0654)the Scientific Research Program of Shaanxi Province (2011K02-06, 2008K02-05)the Scientific Research Program of Shaanxi Province, China(2011K02-06)the Fundamental Research Funds for the Central Universities, China (QN2011012)the Graduate Education Innovation Projects of Henan University of Technology, China (11YJCX45)
文摘Conophylline, is a bis (indole) alkaloid consisting of two pentacyclic aspidosperma skeletons, isolated from Tabernaemontana divaricata, which has been found to induce β-cell differentiation in rat pancreatic acinar carcinoma cells and in cultured rat pancreatic tissue. However, the precise role of conophylline in the growth and survival of immortalized pancreatic mesenchymal stem cells (iPMSCs) derived from fetal porcine pancreas were not understood at present. To determine whether this molecule is involved in controlling the proliferation of iPMSCs, we examined the effects of conophylline on iPMSCs. We found that conophylline can robustly stimulate iPMSCs proliferation, even promote their potential differentiation into islet-like clusters analyzed by cell counting, morphology, RT-PCR and real-time PCR, Western blotting, glucose-stimulated insulin release and insulin content analysis. The effects of conophylline were inhibited by LY294002, which is the inhibitor of the PI3K pathway. These results suggest that conophylline plays a key role in the regulation of cell mass proliferation, maintenance of the undifferentiated state of iPMSCs and also promotes iPMSCs differentiated into insulin-producing cells.
基金Supported by Ministero dell’Universitàe della Ricerca Scientifica e Tecnologica(MURST,ex-60%to GM and EL)
文摘A large body of experimental and clinical data supports the notion that inflammation in acute pancreatitis has a crucial role in the pathogenesis of local and systemic damage and is a major determinant of clinical severity.Thus,research has recently focused on molecules that can regulate the inflammatory processes,such as phosphoinositide 3-kinases(PI3Ks),a family of lipid and protein kinases involved in intracellular signal transduction.Studies using genetic ablation or pharmacologic inhibitors of different PI3 K isoforms,in particular the class I PI3Kδ and PI3Kγ,have contributed to a greater understanding of the roles of these kinases in the modulation of inflammatory and immune responses.Recent data suggest that PI3 Ks are also involved in the pathogenesis of acute pancreatitis.Activation of the PI3K signaling pathway,and in particular of the class IB PI3Kγ isoform,has a significant role in those events which are necessary for the initiation of acute pancreatic injury,namely calcium signaling alteration,trypsinogen activation,and nuclear factor-κB transcription.Moreover,PI3Kγ is instrumental in modulating acinar cell apoptosis,and regulating local neutrophil infiltration and systemic inflammatory responses during the course of experimental acute pancreatitis.The availability of PI3 K inhibitors selective for specific isoforms may provide new valuable therapeutic strategies to improve the clinical course of this disease.This article presents a brief summary of PI3 K structure and function,and highlights recent advances that implicate PI3 Ks in the pathogenesis of acute pancreatitis.