【 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.
Objective To investigate the changes in osteoprotegerin (OPG) / receptor activator of nuclear factor-κB ligand (RANKL) ratio in sepsis-associated acute lung injury (SA-ALI) and the role of regulation of this ratio on the inflammatory response in SA-ALI. Methods Eighteen C57BL/6 male mice were randomly divided into sham operation group, cecal ligation and perforation (CLP) group and RANKL group, with 6 mice in each group. Before the experiment, the RANKL group was intraperitoneally injected with 5 μg (0.2 mL) of recombinant RANKL antibody, whereas both the sham operation group and the CLP group were intraperitoneally injected with a volume-matched normal saline. One hour later, the sham operation group underwent only abdominal exploration and repositioning, while the other groups underwent the CLP surgery to induce the SA-ALI model. After 24 h of modelling, all mice were sacrificed and samples were collected. Pathological evaluation of lung tissues was performed by haematoxylin-eosin staining; enzyme-linked immunosorbent assay was used to detect serum concentrations of interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β; while the mRNA and protein expression of OPG and RANKL, along with their ratio values, were detected by real-time polymerase chain reaction for quantitative analysis and protein immunoblotting. Results The SA-ALI mouse model was successfully established. Compared with the sham operation group, mice in the CLP group showed disturbed alveolar structure, obvious alveolar and interstitial haemorrhage and inflammatory cell infiltration, elevated serum levels of IL-6, TNF-α and IL-1β (P<0.05), significantly increased mRNA and protein expression of OPG and elevated OPG/RANKL ratio in lung tissue (P<0.05), whereas RANKL mRNA and protein expression was significantly decreased (P<0.05). Compared with the CLP group, the pathological damage of lung tissue in the RANKL group was reduced, the infiltration of alveolar and interstitial inflammatory cells was significantly improved, and the alveolar structure and morphology were more regular, with lower serum levels of IL-6, TNF-α and IL-1β (P<0.05), significantly lower mRNA and protein expression of OPG and OPG/RANKL ratio in lung tissue (P<0.05), and significantly higher mRNA and protein expression of RANKL in lung tissue (P<0.05). Conclusion The alteration of OPG/RANKL ratio may be related to the pathophysiological process of SA-ALI, and the decrease in its level may reflect the attenuation of the inflammatory response in SA-ALI.
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.
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 To study the preventive effect of n-3 polyunsaturated fatty acids on allograft arteriosclerosis. Methods Arterial homeotransplant model were created with 480 rats which were divided into four groups. Control group, no n-3 lyunsaturated fatty acids were taken. Group A, n-3 polyunsaturated fatty acids were taken for two weeks before operation with the dose of EPA 600mg/kg. Group B, 300 mg/kg and group C 150 mg/kg were taken respectively. The recipient’s transplanted vessel was excised after 1,7,14,21and 28 days respectively. The tissue pathological variations, ultrastructure variations and expression variations of intercellular adhesion molecule-1(ICAM-1), vascular cell adhesion molecule-1（VCAM-1）, nuclear factorkappa B（NF-κB） had been observed. Results The pathological changes occurred 7 days after operation in control group and were most prominent on the 28th day, blood vessels were obstructed and the expressions of ICAM-1, VCAM1,NF-κB were markedly intensified than those of group A, B, C (Plt;0.05). The pathological variations of transplanted vessel in group A, B, C occurred later than those in control group. The nonobstruction rates in group A, B, C were better than that in control group. The expressions of ICAM-1， VCAM-1， NF-κB in control group were ber than those in group A， B， C (Plt;0.05). The expressions of ICAM-1， VCAM-1， NF-κB after 1 day or 7 days demonstrated no statistically significant change in group A， B， C （Pgt;0.05）. The preventive effect for allograft vessel atheromatosis in group A and group B was ber than that in group C after 14, 21 and 28d (Plt;0.05). There were no significant difference between group A and group B (Pgt; 0.05). Conclusion The n-3 polyunsaturated fatty acids can prevent the allograft vessel atheromatosis, the most effective dose of n-3 polyunsaturated fatty acids is 300 mg/kg.
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.
ObjectiveTo investigate the role and mechanism of P-selectin glycoprotein ligand-1 (PSGL-1) in hydrochloric acid-induced acute lung injury (ALI) in mice.MethodsWild-type mice (WT) and PSGL-1 knockout mice (PSGL-1 -/-) were randomly subjected to normal saline (NS) or hydrochloric acid (HCl) challenged group. The mice were intratracheally instilled with NS or HCl (1 μl/g weight) into the left lung with a catheter. After 2 hours, respiratory function index enhanced pause (Penh), PaO2 and PaO2 were analyzed. The wet to dry weight ratio (W/D) of the left lung and total protein concentration in bronchoalveolar lavage fluid (BALF) were measured. The number of leukocytes in BALF was counted too. Targeted lung tissue was processed for further HE or immunohistochemistry staining. Meanwhile, the expressions of interleukin-6 (IL-6), IL-1β, nuclear factor-κB (NF-κB), IκBa and p-IκBa in lung tissue were measured.ResultsThe Penh (4.77±1.22 vs. 5.80±0.84) and PaCO2 [(63.7±3.9) mm Hg vs. (74.4±7.4) mm Hg] in the PSGL-1 knockout mice were significantly lower than those in the WT mice after HCl stimulation (P<0.05), while the PaO2 was higher than that in the WT mice [(81.0±7.1) mm Hg vs. (62.0±8.9) mm Hg, P<0.05)]. The lung W/D ratio (4.86±0.15 vs. 5.22±0.20), protein concentration [(3.71±0.64) μg/μl vs. (4.74±0.98) μg/μl] and total leukocyte count [(13.00±2.18) ×107/L vs. (49.42±3.35) ×107/L] in BALF were significantly lower in the PSGL-1 knockout mice challenged with HCl than those in the WT mice (P<0.05). Besides, the protein expressions of IL-6, IL-1β, p65 and p-IκBa in the PSGL-1 knockout mice were lower than those in the WT mice after HCl instillation, while the IκBa expression was higher than that in the WT mice (P<0.05). More numbers of neutrophils and macrophages were found in the lung of the WT mice than the PSGL-1 knockout mice challenged with HCl. However, the differences of above values between the WT mice and the PSGL-1 knockout mice instilled with NS were not found, all of which were significantly lower than the correspongding HCl group except for IκBa (P<0.05).ConclusionPSGL-1 may play important roles in the development of HCl-induced ALI via the NF-κB signaling pathway and inflammation.
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.
Behcet's Disease (BD) is a multisystem vasculitis characterized by disease alternated with recurrent episodes and remissions, involving genital, oral, ocular uvea, cutaneous, and articular manifestations. The nuclear factor (NF)-κB signaling pathway paly an important role in the BD progression. It encompasses diverse gene, protein, and cellular regulatory mechanisms operating across various levels, alongside microbiological and experimental studies involving animals and cells. At the protein research findings, activation of the NF-κB pathway in BD patients is marked by elevated plasma levels of soluble CD40 ligand, which stimulates neutrophils to release reactive oxygen species and extracellular traps, thereby promoting inflammation. At the cellular research findings, macrophages in BD patients polarize towards classically activated macrophages phenotype through the NF-κB pathway, exacerbating the inflammatory response. The activation of NF-κB is associated with increased expression of anti-apoptotic proteins in T cells, leading to prolonged inflammation. Microbiological investigations reveal that the decreased gut microbiota diversity in BD patients compromises intestinal barrier integrity. NF-κB pathway involvement in regulating neutrophil and type 1 helper T cell (Th) 1/Th17 cell function worsens inflammation. Genetically, BD patients exhibit polymorphisms in immune regulatory genes, which contribute to inflammation through the NF-κB pathway. Mutations in NF-κB-associated genes elevate the risk of BD, while mutations in the endogenous inhibitor A20 lead to abnormal NF-κB activity, sustaining inflammation. Animal experiments and in vitro experiments corroborate the efficacy of NF-κB inhibitors in attenuating inflammation. Targeting upstream inflammatory factors within the NF-κB pathway yields positive outcomes in BD patients. In summary, the NF-κB signaling pathway plays a pivotal role in the development of BD. Developing NF-κB inhibitors may open new avenues for treating BD. Further research is necessary to comprehensively elucidate the precise mechanisms by which NF-κB operates in the pathogenesis of BD, as well as its potential clinical applications in therapy.
