Antimicrobial peptides: mechanism of action, activity and clinical potential.

The management of bacterial infections is becoming a major clinical challenge due to the rapid evolution of antibiotic resistant bacteria. As an excellent candidate to overcome antibiotic resistance, antimicrobial peptides (AMPs) that are produced from the synthetic and natural sources demonstrate a broad-spectrum antimicrobial activity with the high specificity and low toxicity. These peptides possess distinctive structures and functions by employing sophisticated mechanisms of action. This comprehensive review provides a broad overview of AMPs from the origin, structural characteristics, mechanisms of action, biological activities to clinical applications. We finally discuss the strategies to optimize and develop AMP-based treatment as the potential antimicrobial and anticancer therapeutics.

The Mechanism of miR-222 Targets Matrix Metalloproteinase 1 in Regulating Fibroblast Proliferation in Hypertrophic Scars.

This study aimed to investigate the value of miR-222 in hypertrophic scars (HS). Specific mechanisms were used to measure the level of miR-222, while MTT assay, flow cytometry, western blot and qRT-PCR were employed to detect the relative proteins after fibroblasts were transfected with the miR-222 mimic/inhibitor. The direct target of miR-222 was determined by Dual-Luciferase Reporter assay. Furthermore, qRT-PCR and western blot were employed to detect the matrix metalloproteinase 1 (MMP1) RNA/protein after fibroblasts were transfected with the miR-222 mimic/inhibitor. These results revealed that miR-222 was significantly upregulated in HS fibroblasts. The overexpression of miR-222 enhanced the HS fibroblast proliferation, increased the cell population in the S phase, inhibited the cell apoptosis, enhanced the expression levels of Col1A1, Col3A1 mRNA/protein, proliferating cell nuclear antigen (PCNA), cyclin D1, cyclin E1 and CDK1 and reduced the expression levels of cleaved caspase-3/9. However, the miR-222 suppression triggered opposite effects. Furthermore, miR-222 played a regulatory role in HS by negatively regulating its target gene MMP1 by binding with its 3'-untranslated region. The overexpression of MMP1 reduced the expression levels of PCNA and cyclin D1, but enhanced the expression levels of cleaved caspase-3. Therefore, MiR-222 and MMP1 have potential value for HS. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Isocorydine decrease gemcitabine-resistance by inhibiting epithelial-mesenchymal transition via STAT3 in pancreatic cancer cells.

Gemcitabine is widely used as an anticancer chemotherapy drug for a variety of solid tumors, and it has become the standard treatment option for locally advanced and metastatic pancreatic cancer. However, pancreatic cancer cells develop resistance to gemcitabine after a few weeks of treatment, resulting in poor therapeutic effects. Isocorydine (ICD) is a typical natural aporphine alkaloid, and ICD and its derivatives inhibit the proliferation of many types of cancer cells in vitro. In this study, ICD was found to synergistically inhibit cell viability with gemcitabine in pancreatic cancer cells. A microarray analysis showed that ICD can inhibit the upregulation of STAT3 and EMT in pancreatic cancer cells induced by gemcitabine. STAT3 is closely related to tumor EMT, migration and invasion. After knocking down the expression of STAT3 in pancreatic cancer cells, the combination index (CI) of ICD and gemcitabine decreased. ICD can reverse the increase in the expression of EMT-related transcription factors and proteins caused by gemcitabine, thereby inhibiting the enhanced cell migration and invasion ability caused by gemcitabine. Finally, the synergistic treatment effect of the combination treatment of ICD and gemcitabine in pancreatic cancer cells was confirmed in established xenograft models.

Serum complement C1q level is associated with acute coronary syndrome.

BACKGROUND AND OBJECTIVES: The complement system plays an important role in the development of acute coronary syndrome (ACS). Complement C1q is an important initial component of the classical complement pathway and closely related to many chronic inflammatory diseases, including atherosclerosis (AS). We aimed to determine whether there was association between serum complement C1q and the severity of coronary stenosis. SUBJECTS AND METHODS: 320 patients who underwent coronary arteriography (CAG) were stratified into non-ACS group (control group, n = 74), unstable angina group (UA group, n = 197) and acute myocardial infarction group (AMI group, n = 49) according to the severity of coronary stenosis and clinical manifestations. The severity of coronary stenosis was represented in Gensini score, and serum complement C1q level was compared using immunity transmission turbidity among three groups. RESULTS: The level of complement C1q in AMI group was lower significantly than control group and UA group (P < 0.05), but there was no correlation between serum complement C1q and Gensini score (ß=-0.086, P = 0.125). In nitrate-taking patients, serum complement C1q had a negative association with Gensini score (r=-0.275, P = 0.001), and in non-smokers, there was also a negative correlation (ß=-0.159, P = 0.036). After calibrating smoking, drinking or statins, the serum complement C1q levels of control group, UA group and AMI group decreased in sequence (P <  0.05). Logistic regression analysis showed that the decreasing of serum complement C1q was an unfavorable factor for acute myocardial infarction (OR=0.984, 95 %CI=0.972∼0.997, P = 0.015) and for ACS (OR=0.984, 95 %CI=0.971∼0.984, P = 0.025) in drinking patients. Regrettably, ROC curve suggested that the accuracy in diagnosing coronary atherosclerotic heart disease by serum complement C1q was low (AUC=0.568, 95 %CI= 0.492-0.644, P = 0.076, sensitivity 73.6 %, specificity 58.1 %). CONCLUSION: Serum complement C1q in ACS patients, in particular AMI patients, showed lower level. This finding suggests further decrease of complement C1q level in ACS patients may be a contributory factor to instability or rupture of atherosclerotic plaques. Combined with other clinical indicators, it can be helpful to predict the risk and severity of coronary stenosis.

Diagnosis and surgical treatment of retroperitoneal paraganglioma: A single-institution experience of 34 cases.

The present study aimed at identifying the clinical, radiological and pathological characteristics of retroperitoneal paragangliomas, and determining the association between the tumor features and the prognosis of patients following surgery. A total of 34 patients with retroperitoneal paragangliomas, who underwent resection between November 1999 and December 2015, were included in the present retrospective study. The patients' demographics, clinical symptoms and signs, tumor functional status, surgical procedure, intraoperative results, tumor pathology, radiological results, and postoperative survival time were recorded and analyzed. Of the 34 patients, the most common type of presenting symptom was abdominal mass (46%), followed by hypertension (39%) and abdominal pain (32%). Functional tumors occurred in 20 patients (59%). Computed tomography (CT) and magnetic resonance imaging revealed soft-tissue masses, with marked enhancement in the arterial phase, indicative of retroperitoneal paragangliomas. The preoperative CT diagnostic accuracy rate between 2010 and 2015 was markedly improved, compared with that between 1999 and 2009. The tumors were primarily located close to the renal arteries and veins surrounding the abdominal aorta and inferior vena cava. With the exception of one malignant paraganglioma, the majority of paragangliomas were positive for chromogranin A, S-100 protein, vimentin and heat-shock protein 90, and exhibited decreased expression of Ki-67 antigen and insulin-like growth factor 2. All tumors were completely removed by surgery. Distant metastasis, but not tumor size, functional status and local invasion, was markedly associated with survival. The preoperative diagnostic accuracy rate of retroperitoneal paragangliomas may be improved by focusing on the predilection sites and CT characteristics. In addition, immunohistochemical markers were useful to determine tumor malignancy. Complete surgical resection was appropriate for all patients and postoperative survival time was identified to be associated with tumor metastasis.

BCAT1, a key prognostic predictor of hepatocellular carcinoma, promotes cell proliferation and induces chemoresistance to cisplatin.

BACKGROUND & AIMS: BCAT1 initiates the catabolism of branched-chain amino acids. Here, we investigated the function of BCAT1 and its transcriptional regulatory mechanism in hepatocellular carcinoma (HCC). METHODS: RNASeq was used to evaluate BCAT1 mRNA levels in HCC and normal matched specimens. After the exogenous expression of BCAT1 in BEL-7404 cells and the suppression of endogenous BCAT1 expression with shRNA in HepG2 cells, the cell proliferation, clone-forming ability and cell-cycle changes were measured with MTT assay, colony-forming assay and flow cytometry respectively. A xenograft model was used to investigate the effect of BCAT1 on cancer growth in vivo. Chromatin immunoprecipitation and luciferase reporter technologies were used to confirm the transcriptional regulation of the BCAT1 gene by MYC. The expression of the BCAT1 and MYC proteins in 122 HCC tissues was determined with an immunohistochemical analysis. RESULTS: BCAT1 mRNA was clearly increased in HCC tissues and hepatomas. The ectopic expression of BCAT1 in BEL-7404 cells enhanced their proliferation, clone formation, tumourigenic properties, S-G2 /M phase transition and chemoresistance to cisplatin. The suppression of BCAT1 expression in HepG2 cells significantly inhibited their proliferation, clone formation, and S-G2 /M phase transition and caused their chemosensitization to cisplatin. MYC affected the transcriptional regulation of BCAT1. Clinical data showed that BCAT1 expression correlated with a significantly poorer prognosis. CONCLUSION: BCAT1 plays a pathogenic role in HCC by causing cell proliferation and chemoresistance. The MYC transcription factor is involved in regulating the transcriptional activity of BCAT1. BCAT1 expression has prognostic significance for the survival of patients with HCC.

Bone marrow mesenchymal stem cells promote osteosarcoma cell proliferation and invasion.

BACKGROUND: Bone marrow-derived stem cells (BMSCs) are locally adjacent to the tumor tissues and may interact with tumor cells directly. The purpose of this study was to explore the effects of BMSCs on the proliferation and invasion of osteosarcoma cells in vitro and the possible mechanism involved. METHODS: BMSCs were co-cultured with osteosarcoma cells, and CCK-8 assay was used to measure cell proliferation. The ELISA method was used to determine the concentration of stromal cell-derived factor-1 (SDF-1) in the supernatants. Reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the expression of CXCR4 in osteosarcoma cells and BMSCs. Matrigel invasion assay was performed to measure tumor cell invasion. RESULTS: SDF-1 was detected in the supernatants of BMSCs, but not in osteosarcoma cells. Higher CXCR4 mRNA levels were detected in the osteosarcoma cell lines compared to BMSCs. In addition, conditioned medium from BMSCs can promote the proliferation and invasion of osteosarcoma cells, and AMD3100, an antagonist for CXCR4, can significantly downregulate these growth-promoting effects. CONCLUSIONS: BMSCs can promote the proliferation and invasion of osteosarcoma cells, which may involve the SDF-1/CXCR4 axis.

GSK-3ß suppresses the proliferation of rat hepatic oval cells through modulating Wnt/ß-catenin signaling pathway.

AIM: Glycogen synthase kinase 3ß (GSK-3ß) plays a crucial role in hepatic biology, including liver development, regeneration, proliferation and carcinogenesis. In this study we investigated the role of GSK-3ß in regulation of growth of hepatic oval cells in vitro and in liver regeneration in partially hepatectomized rats. METHODS: WB-F344 cells, the rat hepatic stem-like epithelial cells, were used as representative of oval cells. Cell viability was examined using a WST-8 assay. The cells were transfected with a recombinant lentivirus expressing siRNA against GSK-3ß (GSK-3ßRNAiLV) or a lentivirus that overexpressed GSK-3ß (GC-GSK-3ßLV). Adult rats underwent partial (70%) hepatectomy, and liver weight and femur length were measured at d 7 after the surgery. The expression of GSK-3ß, phospho-Ser9-GSK-3ß, ß-catenin and cyclin D1 was examined with immunoblotting assays or immunohistochemistry. RESULTS: Treatment of WB-F344 cells with the GSK-3ß inhibitor SB216763 (5 and 10 µmol/L) dose-dependently increased the levels of phospho-Ser9-GSK-3ß, but not the levels of total GSK-3ß, and promoted the cell proliferation. Knockout of GSK-3ß with GSK-3ßRNAiLV increased the cell proliferation, whereas overexpression of GSK-3ß with GC-GSK-3ßLV decreased the proliferation. Both SB216763 and GSK-3ßRNAiLV significantly increased the levels of ß-catenin and cyclin D1 in the cells, whereas GSK-3ß overexpression decreased their levels. In rats with a partial hepatectomy, administration of SB216763 (2 mg/kg, ip) significantly increased the number of oval cells, the levels of phospho-Ser9-GSK-3ß, ß-catenin and cyclin D1 in liver, as well as the ratio of liver weight to femur length at d 7 after the surgery. CONCLUSION: GSK-3ß suppresses the proliferation of hepatic oval cells by modulating the Wnt/ß-catenin signaling pathway.

MicroRNA-155 promotes the proliferation and invasion abilities of colon cancer cells by targeting quaking.

The increasing expression of microRNA­155 (miR­155) and decreasing expression of RNA­binding protein quaking (QKI) in colon cells have been observed previously. In this study, we attempted to establish the correlation between miR­155 and QKI. In addition, we assessed whether the expression of miR­155 and QKI is linked to the proliferation and invasion capabilities of colon cells. Firstly, nineteen tumor samples, divided into two groups according to the presence or absence of lymphatic metastasis, were obtained from colon cancer patients at the First Affiliated Hospital of Wenzhou Medical University, China. The expression level of miR­155 and QKI was measured by quantitative polymerase chain reaction (qPCR). Secondly, the GES­1, SW480 and COLO205 cell lines were cultured and the expression level of QKI and miR­155 was also assessed by qPCR. Thirdly, a luciferase reporter gene assay was performed to detect the association between miR­155 and QKI, and qPCR and western blot analysis were performed to confirm the effects of miR­155 on the expression of QKI at the mRNA and protein level. Subsequently, the SW480 cells were used in the following experiments. Following treatment with miR­155 inhibitor and QKI overexpression vector, western blot analysis, propidium iodide (PI) staining and a cell scratch assay were carried out to assess the effects of miR­155 on the proliferation and invasion potential of colon cancer cells. qPCR findings revealed higher miR­155 expression and lower QKI expression in colon cancer tissues as well as the colon cancer cell lines SW480 and COLO205. The relative luciferase activity of the 3' untranslated region (3'UTR) was decreased by approximately 45% when SW480 cells stimulated by mimic­miR­155 were combined with the wild­type 3'UTR constructs. In addition, when the cells were treated with mimic­miR­155, QKI expression was significantly decreased at the mRNA and protein level. These outcomes revealed that miR­155 decreased the production of QKI by acting on the 3'UTR of the QKI gene. Furthermore, PI staining and the cell scratch assay revealed that miR­155 influenced the cell cycle and invasion abilities of colon cancer cells by directly targeting QKI and decreased the production of QKI by acting on the 3'UTR of the QKI gene. This study has demonstrated the correlation between miR­155 and QKI, in which miR­155 regulates the cell cycle and invasion ability of colon cancer cells via the modulation of QKI expression. Our study provides novel therapeutic strategies for colon cancer therapy.

Anticancer effects of baicalein on hepatocellular carcinoma cells.

The therapeutic potential of baicalein against hepatoma cells was evaluated in vitro and in vivo. In cell viability assays, baicalein showed significant cytotoxicity against the hepatocellular carcinoma cell lines H22, Bel-7404, and Hep G2 and moderate cytotoxicity against immortalized human hepatocytes. Baicalein induced G0/G1-phase arrest in hepatocellular carcinoma cells, inhibited AKT, and promoted the degradation of ß-catenin and cyclin D1 without activation of GSK-3ß. Furthermore, baicalein significantly inhibited H22 xenograft tumor growth without causing obvious adverse effects on weight or liver and spleen weight indexes in ICR mice. Immunohistochemical analysis showed that the inhibition of tumor growth in baicalein-treated mice was associated with decreased AKT, ß-catenin, and cyclin D1 expression ex vivo. Our data indicate that baicalein might regulate cyclin D1 transcription via a ß-catenin-dependent mechanism, leading to cell cycle arrest at G0/G1 phase and impaired cancer cell proliferation. These results suggest that baicalein is a potential candidate for the treatment of hepatocellular carcinoma.

Effect of NK4 transduction in bone marrow-derived mesenchymal stem cells on biological characteristics of pancreatic cancer cells.

Pancreatic cancer usually has a poor prognosis, and no gene therapy has yet been developed that is effective to treat it. Since a unique characteristic of bone marrow-derived mesenchymal stem cells (MSCs) is that they migrate to tumor tissues, we wanted to determine whether MSCs could serve as a vehicle of gene therapy for targeting pancreatic cancer. First, we successfully extracted MSCs from SD rats. Next, MSCs were efficiently transduced with NK4, an antagonist of hepatocyte growth factor (HGF) which comprising the N-terminal and the subsequent four kringle domains of HGF, by an adenoviral vector. Then, we confirmed that rat MSCs preferentially migrate to pancreatic cancer cells. Last, MSCs expressing NK4 (NK4-MSCs) strongly inhibited proliferation and migration of the pancreatic cancer cell line SW1990 after co-culture. These results indicate that MSCs can serve as a vehicle of gene therapy for targeting pancreatic cancer.

Correlation between tuberous sclerosis complex 2 and glycogen synthase kinase 3 beta levels, and outcomes of patients with hepatocellular carcinoma treated by hepatectomy.

AIM: Tuberous sclerosis complex 2 (TSC2), a tumor suppressor, may play an essential role in the regulation of cell growth and cell survival under energy stress conditions. In addition, TSC2 may act in concert with Wnt and energy signals by additional phosphorylation of glycogen synthase kinase 3ß (GSK3ß) to regulate cell growth. The expression levels and function of TSC2 and GSK3ß in hepatocellular carcinoma (HCC) remain unclear. METHODS: The protein levels of TSC2 and GSK3ß were measured by immunohistochemistry in normal liver (n = 20), HCC (n = 80) and pericancerous tissues (n = 80). The correlations between TSC2, and GSK3ß levels, clinicopathological features and patient survival were also analyzed. RESULTS: The protein levels of TSC2 and GSK3ß in HCC tissues were significantly lower than that in normal liver tissues and pericancerous tissues (P < 0.05). Decreased TSC2 and GSK3ß expression was found to be significantly correlated with advanced clinicopathological characteristics and poor prognosis. The results also showed that TSC2 protein levels were associated with GSK3ß expression in HCC specimens. CONCLUSION: This is the first demonstration that the decreases in TSC2 and GSK3ß levels may be associated with vascular invasion, histological grade and tumor-node-metastasis classification.

[Regulation effect of adipose-derived mesenchymal stem cells on pancreatic cancer cells].

OBJECTIVE: To analyze the effects of adipose tissue-derived stem cells (ADSCs) on the proliferation and invasion of pancreatic cancer (PaCa) cells and the the possible mechanism involved. METHODS: ADSCs were isolated and co-cultured with PaCa cells. CCK-8 assay was used to detect the proliferation of PaCa cells. An ELISA was used to determine the concentration of stromal cell-derived factor-1 (SDF-1) in the supernatants. The proliferation of PaCa cells by SDF-1 was measured. AMD3100 regulated the co-culture of ADSCs and PaCa. The tumor growth of PaCa cells was assessed after treatment by ADSCs in vivo. RESULTS: ADSCs can promote the proliferation and invasion of PaCa cells (proliferation: SW1990: 1.535 ± 0.153; PANC-1: 1.370 ± 0.100; the value of control was 1; invasion: SW1990: 47.0 ± 2.6 vs. 28.3 ± 1.3; PANC-1: 40.3 ± 1.8 vs. 24.3 ± 1.3; t = 4.332-9.558, P < 0.05). The expression of SDF-1 was high in ADSCs, but not in PaCa cells (69 ± 5 vs. 0 and 0, F = 389.134, P < 0.01). The promotion of SDF-1 on PaCa cells depends on the concentration. AMD3100 significantly downregulates these growth-promoting effects of ADSCs on PaCa cells. ADSCs significantly promoted the growth of SW1990 in nude mice at the 5(th) week (volume: (1295 ± 102) mm(3) vs. (967 ± 81) mm(3), t = 5.614, P < 0.05) , but not in PANC-1 cell. CONCLUSION: ADSCs can promote the proliferation and invasion of PaCa cells, which may involve the SDF-1/CXCR4 axis.

Experimental studies on treatment of pancreatic cancer with double-regulated duplicative adenovirus AdTPHre-hEndo carrying human endostatin gene.

BACKGROUND: Gene-virus targeted therapy is a promising new method of treating pancreatic cancer. To increase the efficacy and decrease the side-effect, we constructed a conditionally replicative adenovirus (CRAd) expressing human endostatin, with a human Telomoerase Reverse Transcriptase (hTERT) promoter for the regulation of the early stage of adenovirus expression of gene E1a and a Hypoxia Response Element (HRE) promoter to regulate the gene E1b. METHODS: A gene recombination technique was adopted to construct and generate the adenovirus AdTPHre-hEndo. Pancreatic cancer cells were studied both in vitro and in vivo. Western blotting was adopted to observe the expressions of protein E1A and E1B; duplication assay was applied to observe the selective duplication capability of recombinant cells. MTT assay was applied to measure the lethal effects of virus on pancreatic cancer cells, and ELISA was adopted to detect the human endostatin gene expression. A pancreatic cancer transplantation tumor model of nude mice was constructed to observe the antitumor effects of the virus. RESULTS: Double-regulated duplicative adenovirus AdTPHre-hEndo genes were successfully constructed. Duplication and lethal assays proved that AdTPHre-hEndo could replicate specifically in pancreatic cancer cells and kill them. The endostatin expression in a cultured supernatant from tumor cells was significantly higher than that obtained from non-duplicative adenovirus vectors carrying that gene. The animal experiment demonstrated that AdTPHre-hEndo has a high capability to limit pancreatic cancer growth. CONCLUSIONS: AdTPHre-hEndo has a special ability to duplicate and kill pancreatic cancer cells in in vitro and in vivo experiments, thus providing a new gene-virus-based treatment system for pancreatic cancer.

Decreased expression of LKB1 correlates with poor prognosis in hepatocellular carcinoma patients undergoing hepatectomy.

AIM: To study any correlation of LKB1 expression with prognosis in hepatocellular carcinoma (HCC) cases. METHODS: A total of 70 HCC patients and 20 primary intrahepatic stone patients in the first affiliated hospital of Wenzhou Medical College were enrolled in this study. LKB1 expression was detected by immunohistochemistry. Patients were followed-up and prognostic factors were evaluated. RESULT: LKB1 expression was decreased in the HCC samples. Loss of LKB1 expression in HCC was significantly related to histologic grade (P=0.010), vascular invasion (P=0.025) and TMN stage (P=0.011). Patients showing negative LKB1 expression had a significantly shorter disease-free and overall survival than those with positive expression (P = 0.001, P=0.000, respectively). Multivariate Cox regression analysis indicated that LKB1 expression level was an independent factor of survival (P = 0.033). CONCLUSION: HCC patients with decreased expression LKB1 have a poor prognosis. The loss of LKB1 expression is correlated with a lower survival rate.

Effectiveness and safety of preoperative percutaneous transhepatic cholangiodrainage with bile re-infusion in patients with hilar cholangiocarcinoma: a retrospective controlled study.

BACKGROUND: Extensive controversies exist over the use of preoperative biliary drainage preceding radical resection of hilar cholangiocarcinoma. This study assessed the effectiveness and safety of percutaneous transhepatic cholangiodrainage (PTCD) with bile re-infusion in the preoperative optimization of hilar cholangiocarcinoma patients. METHODS: Eligible hilar cholangiocarcinoma patients received preoperative PTCD with bile re-infusion (treatment group, n = 56) through a nasoduodenal tube for 2 weeks, and the control group (n = 60) received conservative treatment alone. Operable patients were assigned to undergo either a radical or palliative resection. The outcome measures included the overall resection rate, R0 resection rate, surgical morbidity rate and 1-year and 5-year overall survival rates. RESULTS: The treatment group exhibited a significant decrease in serum bilirubin levels after PTCD with bile re-infusion. The overall resection rate was significantly higher in the treatment group than in the control group (85.5% vs. 65.0%, P < 0.05), and the palliative resection rate was also significantly higher in the treatment group (53.5% vs. 35.0%, P < 0.05). However, the R0 resection rate was comparable between the 2 groups (32.1% vs. 30.0%, P > 0.05). The morbidity rate was significantly lower in the treatment group than in the control group (29.1% vs. 51.3%, P < 0.05). One-year and 5-year survival rates were similar between the 2 groups (69.6% vs. 66.7%, P > 0.05; 5.3% vs. 3.6%, P > 0.05). CONCLUSIONS: Preoperative PTCD with bile re-infusion improves the resection rate and shows a good safety profile in patients with hilar cholangiocarcinoma.

Lentiviral vector-mediated down-regulation of IL-17A receptor in hepatic stellate cells results in decreased secretion of IL-6.

AIM: To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A receptor (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro. METHODS: HSCs were derived from the livers of adult male Sprague-Dawley rats. IL-6 expression was evaluated using real-time quantitative polymerase chain reaction and enzyme linked immunosorbent assay. The phosphorylation activity of p38 mitogen activated protein kinases (MAPK) and extracellular regulated protein kinases (ERK) 1/2 upon induction by IL-17A and suppression by IL-17RA shRNA were examined using Western blotting. RESULTS: IL-6 expression induced by IL-17A was significantly increased compared to control in HSCs (P < 0.01 in a dose-dependent manner). Suppression of IL-17RA using lentiviral-mediated shRNA inhibited IL-6 expression induced by IL-17A compared to group with only IL-17A treatment (1.44 ± 0.17 vs 4.07 ± 0.43, P < 0.01). IL-17A induced rapid phosphorylation of p38 MAPK and ERK1/2 after 5 min exposure, and showed the strongest levels of phosphorylation of p38 MAPK and ERK1/2 at 15 min in IL-17A-treated HSCs. IL-6 mRNA expression induced by IL-17A (100 ng/mL) for 3 h exposure was inhibited by preincubation with specific inhibitors of p38 MAPK (SB-203580) and ERK1/2 (PD-98059) compared to groups without inhibitors preincubation (1.67 ± 0.24, 2.01 ± 0.10 vs 4.08 ± 0.59, P < 0.01). Moreover, Lentiviral-mediated IL-17RA shRNA 1 inhibited IL-17A-induced IL-6 mRNA expression compared to random shRNA in HSCs (1.44 ± 0.17 vs 3.98 ± 0.68, P < 0.01). Lentiviral-mediated IL-17RA shRNA 1 inhibited phosphorylation of p38 MAPK and ERK1/2 induced by 15 min IL-17A (100 ng/mL) exposure. CONCLUSION: Down-regulation of the IL-17RA receptor by shRNA decreased IL-6 expression induced by IL-17A via p38 MAPK and ERK1/2 phosphorylation in HSCs. Suppression of IL-17RA expression may be a strategy to reduce the inflammatory response induced by IL-17A in the liver.

Continuous regional arterial infusion with fluorouracil and octreotide attenuates severe acute pancreatitis in a canine model.

AIM: To investigate the therapeutic effects of fluorouracil (5-Fu) and octreotide (Oct) continuous regional arterial infusion (CRAI,) alone or in combination, was administered in a canine model of severe acute pancreatitis (SAP). MATERIALS AND METHODS: The animals were divided into five groups; group A (Sham), group B (SAP), group C (SAP and 5-Fu), group D (SAP and Oct), and group E (SAP and 5-Fu + Oct). Levels of amylase, α-tumor necrosis factor (TNF-α), blood urea nitrogen (BUN), creatinine, thromboxane B2 and 6-keto- prostaglandin F1α were measured both before and after the induction of SAP. Pathologic examination of the pancreas and kidneys was performed after termination of the study. RESULTS: Pathologic changes noted in the pancreas in SAP significantly improved following CRAI with either single or combined administration of 5-Fu and Oct, where combination therapy demonstrated the lowest injury score. All treatment groups had significantly lower levels of serum TNF-α and amylase activity (P<0.05), though only groups D and E had a lower BUN level as compared to group B. The plasma thromboxane B(2) level increased in SAP, but the ratio of thromboxane B(2)/6-keto- prostaglandin F(1α) decreased in the treatment groups, with the combination therapy (group E) demonstrating the lowest ratio as compared to the other 3 experimental groups (P<0.05). CONCLUSIONS: The findings in the present study demonstrate an attenuation of SAP in a canine model following CRAI administration with 5-Fu or Oct, alone or in combination.