Objective To observe the effect of epidermal growth factor (EGF) on the proliferation, adhesion, invasiveness and the activation of nuclear factor-κB (NF-κB), matrix metalloproteinases (MMPs) expression and explore related mechanisms in pancreatic cancer cells. Methods Cell invasion assay, proliferation assay and adhesion assay were used to examine the proliferation, adhesion and invasiveness of pancreatic cancer cells, respectively. NF-κB activity was detected by electrophoretic mobility shift assay (EMSA), and MMPs protein and mRNA expressions were investigated by gelatin zymography, Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). Results EGF increased the invasiveness of pancreatic cancer cell in a dose-dependent manner (P＜0.05), but did not affect cell proliferation or adhesion. The expressions of MMP-9 mRNA and protein significantly increased after induction by EGF and were highest when EGF concentration was 50 ng/ml, while there was no effect on the expressions of MMP-2 mRNA and protein. Furthermore, NF-κB activity increased with increased concentration of EGF in a concentration-dependent manner (P＜0.05). In addition, NF-κB activity and the expressions of MMP-9 mRNA and protein by pretreatment with both pyrrolidine dithiocarbamate (PDTC) and EGF decreased when compared that by pretreatment with EGF alone. The invasiveness of pancreatic cancer cell by pretreatment with both PDTC and EGF decreased when compared that by pretreatment with EGF alone and nothing (P＜0.05).Conclusion The findings indicate that the NF-κB-mediated MMP-9 induction is essential for EGF-induced invasiveness in pancreatic cancer cells, which can be inhibited by PDTC.
Objective To study the expression of nuclear factor-κBp65 (NF-κBp65) in gastric carcinoma and its relationship with vascular endothelial growth factor (VEGF). Methods The expression of NF-κBp65 and VEGF in 56 gastric carcinomas was detected with immunohistochemistry and compared with benign tissues. Results The positive rates of NF-κBp65 and VEGF in 56 gastric carcinomas were 62.5% and 76.8% respectively,and which were higher than those of gastric mucosal atypical hyperplasia (33.3% and 44.4%) and the normal gastric mucosa(0 and 8.3%) （P＜0.05,P＜0.01）.It was found that there was relationship between the expression of NF-κBp65 and the clinical stage, invasion depth of tumor and lymph node metastasis (P＜0.05),but there was no relation to the historica type (Pgt;0.05). There was positive correlation between NF-κBp65 and VEGF expression （r=0.36,P＜0.01）. Conclusion NF-κBp65 may play an important role in the development of gastric carcinoma by up-regulate the expression of VEGF.
ObjectiveTo discuss the role of nuclear factor-kappa B in restenosis after angioplasty.MethodsRelated literatures of recent 5 years were reviewed.ResultsNuclear factor-kappa B could lead to hyperplasia of vascular intima which resulted from proliferation and decrease of apoptosis of vascular smooth muscle cells.ConclusionNuclear factor-kappa B plays an important role in restenosis after angioplasty.
Objective To investigate the expression changes of nuclear factor kappa B (NF-κB) and matrix metalloproteinase-9 (MMP-9) in the cultured hepatocellular carcinoma cells 9204 (HCC9204) transfected with inhibitory kappa B alpha（IκB-α)vector. Methods After pcDNA3-IκB-α vector and pcDNA3 were transfected into HCC9204 by lipofectamine method, Western-blot and RT-PCR analysis were used to detect the expressions of NF-κB and MMP-9. Migration and invasion of tumor cells were assayed by fundus membrane invaded by them. Results When pcDNA3-IκB-α was transfected into HCC9204, the expression of NF-κB was decreased at the protein level, and the expression of MMP-9 mRNA and the invision and metastasis ability of transfected cells were obviously decreased. Conclusion When the activity of NF-κB is inhibited, the ability of invasion and metastasis in HCC9204 cells decrease, which could be related to the decreased the expression of MMP-9.
【 Abstract 】 Objective Overexpressions of epidermal growth factor (EGF) and EGF receptor have been associated with progression and invasive phenotype of pancreatic cancer. However, the underlying molecular mechanism by which EGF worked in pancreatic cancer cells has not been completely understood. In this study, effect of EGF on the invasion and metastasis of pancreatic cancer cells and its regulatory mechanism were investigated. Methods The effects of EGF on the proliferation, adhesion and invasion of pancreatic cancer cells were detected by WST-1 proliferation assay, adhesion assay and invasive assay, respectively. The activity and expression of MMP-2 and MMP-9 were examined by zymography, Western blot and RT-PCR, respectively. The activity of NF- κ B was examined by EMSA. Results EGF could significantly promote the invasiveness of pancreatic cancer cells but did not affect cell proliferation or adhesion. The expressions of NF- κ B and MMP-9 were significantly increased by EGF, but EGF did not affect the activity and expression of MMP-2. Furthermore, EGF stimulated the NF- κ B binding activity. Pretreatment with NF- κ B inhibitors, pyrrolidine dithiocarbamate (PDTC), could significantly inhibit the activity of NF- κ B induced by EGF. Meanwhile, the EGF-induced expression and activity of MMP-9, as well as cell invasiveness were also inhibited by NF- κ B inhibitor. Conclusion EGF could increase the expression and promote the invasiveness of MMP-9 via the activation of NF- κ B in pancreatic cancer cells, which implies that NF- κ B inhibitant, such as PDTC, may diminish the invasiveness of pancreatic cancer cells.
ObjectiveTo investigate the possible protective effect of zerumbone on pancreatic injury in severe acute pancreatitis (SAP) rats, and to provide a theoretical basis for prevention and treatmen of severe acute pancreatitis. MethodsSeventy male Wistar rats were randomly divided into four groups:normal control group (NC group, n=10), SAP group (n=40), Zerumbone pretreatment group (ZER group, n=10), and Zerumbone drug control group (ZER-CON group, n=10). Rats of SAP group were divided into four time points of 1 h, 3 h, 6 h, and 12 h (n=10 each time point). SAP models were induced by retrograde injection of 5% sodium taurocholate (0.1 mL/100 g) in biliopancreatic duct in SAP group and ZER group. Rats were injected isotonic saline solution instead of taurocholate as a control in NC group and ZER-CON group. Zerumbone solution (10 mg/kg) was administered via femoral vein half an hour prior to establishing models in ZER group and ZER-CON group. All rats except SAP group were sacrificed at 12 h time point after the induction of SAP. The rats in SAP group were sacrificed at 1 h, 1 h, 3 h, 6 h and 12 h time point after induction of SAP. The mortality, ascites, serum amylase (AMY), phospholipase, and pathological examination of pancreas were observated or detected. The expression of nuclear factor-kappa B (NF-κB) p65 in pancreatic tissues was evaluated by immunohistochemistry assay. ResultsThere were no difference of the levels of mortality, ascites, serum AMY, phospholipase, pathological examination, and NF-κB p65 location expression of pancreas between the ZER-CON group and NC group (P>0.05). The above indexes in SAP group were significantly higher than those in NC group (P<0.05). However, those in ZER group were significantly lower than in SAP group (P<0.05), and higher than in NC group (P<0.05). ConclusionsZerumbone can reduce the mortality and ascites, effectively alleviate the enzyme, pathological injury, and NF-κB p65 location expression in pancreatic tissue following SAP. It may indicate that zerumbone can protect pancreatic injury in SAP via NF-κB pathway.
目的探讨髓样细胞分化蛋白88（MyD88）在重症急性胰腺炎（SAP）发病机理的作用。 方法将48只小鼠按随机数字表法随机分为SAP组（32只）与正常对照组（16只）；再将2组小鼠随机（随机数字表法）分为6、12、24及48 h组，SAP组各亚组每组8只，正常对照组每亚组4只。SAP组小鼠腹腔注射20% L-精氨酸以诱导SAP模型，正常对照组小鼠仅腹腔注射生理盐水。分别于建模术后6、12、24及48 h处死小鼠，取其动脉血，采用ELISA方法检测血清中白细胞介素-1β（IL-1β）、白细胞介素-10（IL-10）及肿瘤坏死因子-α（TNF-α）浓度；同时取其胰腺组织（正常对照组仅术后6 h取材），用逆转录-聚合酶链反应（RT-PCR）方法检测胰腺组织中MyD88 mRNA和核因子-κB（NF-κB）mRNA的表达水平，并进行HE染色。 结果镜下见SAP组小鼠的胰腺组织随时间进展其炎症逐渐加重。各时点SAP组小鼠的IL-1β、IL-10及TNF-α浓度均高于正常对照组（P＜0.05）；各时点SAP组与正常对照组（6 h组）相比较，其胰腺组织中MyD88 mRNA及NF-κB mRNA的表达水平均较高（P＜0.05）。各时点SAP组小鼠MyD88 mRNA的表达水平与血清IL-1β、IL-10及TNF-α的浓度和NF-κB mRNA的表达水平均呈正相关（P＜0.01）。 结论MyD88的表达对SAP的发生和发展可能均具有重要的作用。
ObjectiveTo explore the protective mechanism and effect of the resveratrol for kidney injury of obstructive jaundice. MethodsThe rats were randomly divided into three groups: sham operation group receiving laparotomy without bile duct ligation (BDL), the obstructive jaundice group with BDL, and the obstructive jaundice + resveratrol group given resveratrol following BDL. The levels of total bilirubin (TBIL), direct bilirubin (DBIL), blood urea nitrogen (BUN), and creatinine (Cr) in the serum were tested. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, glutathione (GSH) level in the renal tissues were detected. The expressions of the silent information regulator 1 (SIRT1) and nuclear factor-κB (NF-κB) proteins were tested by Western blot. The expression of SIRT1 mRNA was detected by RT-PCR and the renal cell apoptosis was examined by TUNEL staining. Results①Compared with the sham operation group, the levels of serum TBIL, DBIL, BUN and Cr were significantly higher (P < 0.05); the activity of SOD and level of GSH, and the expressions of SIRT1 mRNA and SIRT1 protein in the renal tissues were signi-ficantly lower (P < 0.05); the content of MDA, the expression of NF-κB protein, and the rate of cell apoptosis in the renal tissues were significantly higher (P < 0.05) in the obstructive jaundice group.②Compared with the obstructive jaundice group, the levels of serum TBIL, DBIL, BUN and Cr were significantly lower (P < 0.05); the activity of SOD and level of GSH, and the expressions of SIRT1 mRNA and SIRT1 protein in the renal tissues were significantly higher (P < 0.05); the content of MDA, the expression of NF-κB protein, and the rate of cell apoptosis in the renal tissues were significantly lower (P < 0.05) in the obstructive jaundice+resveratrol group. ConclusionThe resveratrol could alleviate renal damage and play a beneficial role to resist inflammation, oxidation, and apoptosis by activating the SIRT1 which probably inhibits the expression of NF-κB protein and promotes the activity of SOD in cholestatic kidney injury.
Vascular smooth muscle cells (VSMCs) phenotype switching plays an essential role in the pathogenesis of various vascular diseases. The present study aims to investigate the role of receptor-interacting protein kinases 1(RIPK1) in VSMCs phenotypic switching induced by Angiotensin Ⅱ(Ang Ⅱ). Expression of mRNA and protein of RIPK1, markers of VSMCs phenotypic switching and secretion, phosphorylation of the P65 subunit of NF-κB were measured by real-time PCR and Western blot. Meanwhile, EdU incorporation assay and wound scratch assay were performed to determine the cell proliferation and migration respectively. At the same time, Necrostatin-1(Nec-1, an known RIPK1 inhibitor) and RIPK1-specific small interference RNA (siRNA) were used to inhibit the expression of RIPK1. The experimental data demonstrated that the mRNA and protein levels of RIPK1 and P65 phosphorylation were increased significantly in the process of VSMC phenotypic switching induced by Ang II. Moreover, the expression of RIPK1 and P65 phosphorylation were significantly down-regulated in VSMCs pretreated with Nec-1 or trans-fected with RIPK1-siRNA. Furthermore, the proliferation, secretion and migration of VSMCs were also markedly suppressed after inhibition of RIPK1 by Nec-1 or its specific siRNA. The results suggested that RIPK1 might be involved in VSMC phenotypic switching induced by Ang II, which was possibly via up-regulating the NF-κB signaling pathway.
Objective To observed the effect of IL-1β on expression of caudal-related homeobox gene 1 (CDX1) mRNA and mucoprotein 2 (MUC2) mRNA in cultured human gastric epithelial cells GES-1, and to investigate the underlying signal transduction pathways. Methods ①GES-1 cell was activated with IL-1β of different concentrations and time, the expression levels of CDX1 mRNA and MUC2 mRNA were detected by using real-time PCR. ②GES-1 cell was pretreated with PDTC, a NF-κB inhibitor, for 1 h prior to the addition of IL-1β, then the expressions of CDX1 mRNA and MUC2 mRNA were measured. Results Both CDX1 mRNA and MUC2 mRNA were not examined in GES-1 cell under normal culture conditions. But they could be induced by IL-1β with a dose-dependent manner in a concentration range (P＜0.05); 8 h after treatment with IL-1β, the peak values of the expression levels of CDX1 mRNA and MUC2 mRNA were reached (P＜0.05), then declined gradually. When pre-incubated with NF-κB inhibitor PDTC, the expression levels of CDX1 mRNA and MUC2 mRNA were significantly decreased (P＜0.05). Conclusion IL-1β significantly induces the expressions of CDX1 mRNA and MUC2 mRNA in cultured human gastric epithelial cell GES-1 through the NF-κB signal pathway, which indicates that IL-1β plays a role in the process of intestinal metaplasia.