Selective COX-2 inhibitor, NS-398, suppresses cellular proliferation in human hepatocellular carcinoma cell lines via cell cycle arrest

Suppressing growth and invasion of human hepatocellular carcinoma cells by celecoxib through inhibition of cyclooxygenase-2

Purpose: Biomarkers are lacking in hepatocellular carcinoma (HCC). Cyclooxygenase-2 (COX-2) and its metabolites play crucial roles in the process of inflammation-tumor transformation. This study was aimed to detect COX-2 expression in HCC tissues and evaluate the effects of a COX-2 inhibitor, celecoxib, on biological behaviors of HCC cell lines in vitro.

Methods: COX-2 expression was detected by immunohistochemistry on a human HCC tissue microarray. The correlations of COX-2 expression with tumor clinicopathological variables and overall survival were analyzed. The proliferation, apoptosis, cell cycle distribution, invasion capacity, and related signaling molecules of HCC cells after incubated with COX-2 inhibitor celecoxib were evaluated in vitro.

Results: Expression levels of COX-2 in HCC tissues were significantly higher than those in paracancerous tissues. The TNM stage III-IV, tumor size >5 cm, lymphovascular invasion and distant metastasis was higher in high COX-2 expression group compared with that in low COX-2 expression group. Patients with low COX-2 expression achieved better 5-year overall survival than those with high COX-2 expression. Treatment with celecoxib was sufficient to inhibit cell proliferation, promote apoptosis, and induce G0/G1 cell cycle arrest in HCC cells with concentration- and time-dependent manners. Celecoxib up-regulated E-cadherin protein through inhibiting COX-2-prostaglandin E2 (PGE2)-PGE2 receptor 2 (EP2)-p-Akt/p-ERK signaling pathway to suppress HCC cells migration and invasion.

Conclusion: High COX-2 expression was associated with advanced TNM stage, larger tumor size, increased lymphovascular invasion and short survival. Targeting inhibition of COX-2 by celecoxib exhibited anti-tumor activities by suppressing proliferation, promoting apoptosis, and inhibiting the aggressive properties of HCC cells.

The Role of Myeloid-Derived Suppressor Cells in Patients with Solid Tumors: A Meta-Analysis

Targeting immune cells or factors are effective for patients with solid tumors. Myeloid-derived suppressor cells (MDSCs) are known to have immunosuppressive functions, and the levels of MDSCs in patients with solid tumor are assumed to have prognostic values. This meta-analysis aimed at evaluating the relationship between MDSCs and the prognosis of patients with solid tumors. We searched articles in PUBMED and EMBASE comprehensively, updated to March 2016. Eight studies with 442 patients were included in the meta-analysis. We analyzed pooled hazard ratios (HRs) for overall survival (OS), disease-free survival (DFS) and progression-free survival (PFS). The results showed that MDSCs were associated with poor OS (HR, 1.94; 95% confidence interval [CI], 1.42-2.66; P < 0.0001) in patients with solid tumors. PFS/RFS (HR, 1.85; 95% CI, 1.16-2.97; P = 0.01) also indicated the association between MDSCs and prognosis. The HRs and 95% CIs for OS in Asian and non-Asian patients were 2.53 (95% CI 1.61-3.42, p < 0.00001) and 1.67 (95% CI 1.14-2.46, p < 0.0001), respectively. We further analyzed the data according to tumor types. The combined HRs and 95% CIs for OS were 1.26 (95% CI 1.10-1.44, p = 0.0003) for gastrointestinal (GI) cancer, 2.59 (95% CI 1.69-3.98, p < 0.0001) for hepatocellular carcinoma (HCC) and 1.86 (95% CI 1.26-2.75, p = 0.002) for other tumor types. In conclusion, MDSCs had a fine prognostic value for OS and PFS/RFS in patients with solid tumors. MDSCs could be used as biomarkers to evaluate prognosis in clinical practice.

Fibroblast Growth Factor Signaling Controls Liver Size in Mice With Humanized Livers

BACKGROUND & AIMS

The ratio of liver size to body weight (hepatostat) is tightly controlled, but little is known about how the physiologic functions of the liver help determine its size. Livers of mice repopulated with human hepatocytes (humanized livers) grow to larger than normal; the human hepatocytes do not recognize the fibroblast growth factor (FGF)-15 produced by mouse intestine. This results in up-regulation of bile acid synthesis in the human hepatocytes and enlargement of the bile acid pool. We investigated whether abnormal bile acid signaling affects the hepatostat in mice.

METHODS

We crossed Fah(-/-), Rag2(-/-), Il2r(-/-) mice with nonobese diabetic mice to create FRGN mice, whose livers can be fully repopulated with human hepatocytes. We inserted the gene for human FGF19 (ortholog to mouse Fgf15), including regulatory sequences, into the FRGN mice to create FRGN19(+) mice. Livers of FRGN19(+) mice and their FRGN littermates were fully repopulated with human hepatocytes. Liver tissues were collected and bile acid pool sizes and RNA sequences were analyzed and compared with those of mice without humanized livers (controls).

RESULTS

Livers were larger in FRGN mice with humanized livers (13% of body weight), compared with control FRGN mice; they also had much larger bile acid pools and aberrant bile acid signaling. Livers from FRGN19(+) normalized to 7.8% of body weight, and their bile acid pool and signaling more closely resembled that of control FRGN19(+) mice. RNA sequence analysis showed activation of the Hippo pathway, and immunohistochemical and transcription analyses revealed increased hepatocyte proliferation, but not apoptosis, in the enlarged humanized livers of FRGN mice. Cell sorting experiments showed that although healthy human liver does not produce FGF19, nonparenchymal cells from cholestatic livers produce FGF19.

CONCLUSIONS

In mice with humanized livers, expression of an FGF19 transgene corrects bile acid signaling defects, resulting in normalization of bile acid synthesis, the bile acid pool, and liver size. These findings indicate that liver size is, in part, regulated by the size of the bile acid pool that the liver must circulate.

The elevated preoperative neutrophil-to-lymphocyte ratio predicts poor prognosis in intrahepatic cholangiocarcinoma patients undergoing hepatectomy

A high preoperative peripheral blood neutrophil-to-lymphocyte ratio (NLR) has been reported to be a predictor of poor survival in patients with various cancers. The aim of this study was to evaluate the predictive significance of the NLR in patients undergoing hepatectomy for intrahepatic cholangiocarcinoma (ICC). From 2005 to 2011, 322 patients who underwent hepatectomy for ICC were enrolled in this retrospective study. Clinicopathological parameters, including NLR, were evaluated to identify predictors of overall and recurrence-free survival after hepatectomy. The best cutoff for NLR was 2.49, and 177 of 322 patients (54.9 %) had an NLR ≥ 2.49. The 5-year survival rate after hepatectomy was 51.1 % in patients with NLR < 2.49 and 24.8 % in those with NLR ≥ 2.49 (P = 0.0001). Univariate analyses revealed that NLR was significantly associated with recurrence-free survival (RFS) and overall survival (OS; both P < 0.05). Multivariable analyses revealed that elevated NLR independently predicted poorer OS (P = 0.003, hazard ratio [HR] = 1.600). In summary, our results indicate that elevated NLR is a promising independent predictor of poor survival after hepatectomy in patients with ICC.

Nimesulide inhibits the growth of human esophageal carcinoma cells by inactivating the JAK2/STAT3 pathway

Although selective COX-2 inhibitors have cancer-preventive effects and induce apoptosis, the mechanisms underlying these effects are not fully understood. This study investigated the effects of nimesulide, a selective COX-2 inhibitor, on apoptosis and on the JAK/STAT signaling pathway in Eca-109 human esophageal squamous carcinoma cells. The effects and mechanisms of nimesulide on Eca-109 cell growth were studied in culture and in nude mice with Eca-109 xenografts. Cells were cultured with or without nimesulide and/or the JAK2 inhibitor AG490. Cell proliferation was evaluated using the MTT assay, and apoptosis was investigated. COX-2 mRNA expression was measured using reverse transcription polymerase chain reaction, and protein expression was detected by Western blot analysis, immunohistochemistry, and flow cytometry. Nimesulide significantly inhibited Eca-109 cell viability in vitro in a dose- and time-dependent manner (P<0.05). Nimesulide also induced apoptosis, which was accompanied by a significant decrease in the expression of COX-2 and survivin and an increase in caspase-3 expression. Nimesulide downregulated the phosphorylation levels of JAK2 and STAT3, and JAK2 inhibition by AG490 significantly augmented both nimesulide-induced apoptosis and the downregulation of COX-2 and survivin (P<0.05). In vivo, nimesulide inhibited the growth of Eca-109 tumors and the expression of p-JAK2 and p-STAT3. Thus, nimesulide downregulates COX-2 and survivin expression and upregulates caspase-3 expression in Eca-109 cells, by inactivating the JAK2/STAT3 pathway. These effects may mediate nimesulide-induced apoptosis and growth inhibition in Eca-109 cells in vitro and in vivo.

Anti inflammatory and anti angiogenic effect of black raspberry extract on human esophageal and intestinal microvascular endothelial cells

Polyphenolic compounds (anthocyanins, flavonoid glycosides) in berries prevent the initiation, promotion, and progression of carcinogenesis in rat's digestive tract and esophagus, in part, via anti-inflammatory pathways. Angiogenesis has been implicated in the pathogenesis of chronic inflammation and tumorigenesis. In this study, we investigated the anti-inflammatory and anti-angiogenic effects of black raspberry extract (BRE) on two organ specific primary human intestinal microvascular endothelial cells, (HIMEC) and human esophageal microvascular endothelial cells (HEMEC), isolated from surgically resected human intestinal and donor discarded esophagus, respectively. HEMEC and HIMEC were stimulated with TNF-α/IL-1β with or without BRE. The anti-inflammatory effects of BRE were assessed based upon COX-2, ICAM-1 and VCAM-1 gene and protein expression, PGE2 production, NFκB p65 subunit nuclear translocation as well as endothelial cell-leukocyte adhesion. The anti-angiogenic effects of BRE were assessed on cell migration, proliferation and tube formation following VEGF stimulation as well as on activation of Akt, MAPK and JNK signaling pathways. BRE inhibited TNF-α/IL-1β-induced NFκB p65 nuclear translocation, PGE2 production, up-regulation of COX-2, ICAM-1 and VCAM-1 gene and protein expression and leukocyte binding in HEMEC but not in HIMEC. BRE attenuated VEGF-induced cell migration, proliferation and tube formation in both HEMEC and HIMEC. The anti-angiogenic effect of BRE is mediated by inhibition of Akt, MAPK and JNK phosphorylations. BRE exerted differential anti-inflammatory effects between HEMEC and HIMEC following TNF-α/IL-1β activation whereas demonstrated similar anti-angiogenic effects following VEGF stimulation in both cell lines. These findings may provide more insight into the anti-tumorigenic capacities of BRE in human disease and cancer.

Antioxidative dietary compounds modulate gene expression associated with apoptosis, DNA repair, inhibition of cell proliferation and migration

Many dietary compounds are known to have health benefits owing to their antioxidative and anti-inflammatory properties. To determine the molecular mechanism of these food-derived compounds, we analyzed their effect on various genes related to cell apoptosis, DNA damage and repair, oxidation and inflammation using in vitro cell culture assays. This review further tests the hypothesis proposed previously that downstream products of COX-2 (cyclooxygenase-2) called electrophilic oxo-derivatives induce antioxidant responsive elements (ARE), which leads to cell proliferation under antioxidative conditions. Our findings support this hypothesis and show that cell proliferation was inhibited when COX-2 was down-regulated by polyphenols and polysaccharides. Flattened macrophage morphology was also observed following the induction of cytokine production by polysaccharides extracted from viili, a traditional Nordic fermented dairy product. Coix lacryma-jobi (coix) polysaccharides were found to reduce mitochondrial membrane potential and induce caspase-3- and 9-mediated apoptosis. In contrast, polyphenols from blueberries were involved in the ultraviolet-activated p53/Gadd45/MDM2 DNA repair system by restoring the cell membrane potential. Inhibition of hypoxia-inducible factor-1 by saponin extracts of ginsenoside (Ginsen) and Gynostemma and inhibition of S100A4 by coix polysaccharides inhibited cancer cell migration and invasion. These observations suggest that antioxidants and changes in cell membrane potential are the major driving forces that transfer signals through the cell membrane into the cytosol and nucleus, triggering gene expression, changes in cell proliferation and the induction of apoptosis or DNA repair.

Abnormal COX2 protein expression may be correlated with poor prognosis in oral cancer: a meta-analysis

Background. The prognostic significance of COX2 for survival of patients with oral cancer remains controversial. Thus, the meta-analysis was performed in order to identify COX2 expression impact on prognosis of oral cancer. Method. Relevant literatures were searched using the following electronic databases without any language restrictions: Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, and CBM. Version 12.0 STATA software (Stata Corporation, College Station, Texas, USA) was used for the current meta-analysis. Odds ratios (ORs) and hazard ratios (HRs) with their corresponding 95% confidence interval (95% CI) were also calculated to clarify the correlation between COX2 expression and prognosis of oral cancer. Results. Final analysis of 979 oral cancer patients from 12 clinical cohort studies was performed. The meta-analysis results show that COX2 expression in cancer tissues was significantly higher than those in normal and benign tissues (all P < 0.05). Combined HR of COX2 suggests that positive COX2 expression has a shorter overall survival (OS) than those of negative COX2 expression (P < 0.05). Conclusion. The meta-analysis study shows that elevated COX2 expression may be associated with the pathogenesis of oral cancer and with a worse prognosis in oral cancer patients.

Inhibition of HepG2 cell proliferation by ursolic acid and polysaccharides via the downregulation of cyclooxygenase-2

Cyclooxygenase (COX)-2, a multi-functional molecule, is overexpressed in hepatocellular carcinomas. In order to understand cell proliferation and its association with COX-2 in HepG2 cells in the presence of ursolic acid (UA), viili exopolysaccharides (VEPS) and Astragalus polysaccharides (APS), the cell proliferation, superoxide dismutase (SOD) and metabolic malondialdehyde (MDA) of fatty acids, COX-2, prostaglandin E2 (PGE2), as well as apoptotic morphology and rate were investigated. The results revealed that the activities of SOD, COX-2 and PGE2 were reduced, MDA was markedly decreased, apoptotic blebs were induced, and HepG2 cells were accumulated in the G1 and sub G1/apoptotic phases in test groups. The results indicated that UA, VEPS, APS and any combination of these possess anticancer properties, particularly by downregulating COX-2 expression, which may have increased internal oxidation and triggered apoptosis together with a change in internal antioxidant response elements, leading to a reduction in cell proliferation.

Celecoxib regulates apoptosis and autophagy via the PI3K/Akt signaling pathway in SGC-7901 gastric cancer cells

Gastric cancer, one of the most common malignancies worldwide, typically has a poor prognosis and poor survival rate. Previous studies have investigated the chemopreventive effect of celecoxib. In the present study, the SGC-7901 human gastric cancer cell line was utilized to examine the chemopreventive mechanisms of celecoxib. The inhibition of cell proliferation was determined using MTT assay, cell apoptosis was monitored by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) and flow cytometry, and cell ultrastructural changes were assessed via transmission electron microscopy. The mRNA expression of Akt, caspase-8 and -9 was examined using quantitative reverse-transcription-polymerase chain reaction (qRT-PCR) and p-Akt, procaspase-8 and -9 were analyzed via western blotting. The results showed that celecoxib inhibited the proliferation of SGC-7901 cells in a time- and dose-dependent manner. Additionally, celecoxib induced apoptosis as substantiated by typical apoptotic bodies, autophagosomes and an increased apoptotic rate. It was found that following celecoxib treatment, Akt mRNA expression was not significantly altered, and that p-Akt protein levels decreased in a time- and dose-dependent manner. Additionally, caspase-8 and -9 mRNA expression was significantly increased, while procaspase-8 and -9 protein expression decreased relative to the time- and dose-dependent effects. These results demonstrated that celecoxib induced apoptosis and autophagy of gastric cancer cells in vitro through the PI3K/Akt signaling pathway. Moreover, our findings suggested that celecoxib induces apoptosis in gastric cancer cells through the mitochondrial and death receptor pathways, providing additional understanding regarding the chemopreventive behaviors of celecoxib and its uses in cancer therapy.

The inhibitory effect of a novel polypeptide fraction from Arca subcrenata on cancer-related inflammation in human cervical cancer HeLa cells

Inflammation is known to be closely associated with the development of cancer. The study was launched in human cervical cancer HeLa cells to investigate the antitumor and anti-inflammatory effects of P2, a marine polypeptide fraction from an important fishery resource Arca subcrenata. The basic research showed that P2 could suppress the production of nitric oxide in LPS-induced RAW264.7 macrophage cells as well as the secretion of inflammatory cytokines IL-6 and TNF- α in human cervical cancer HeLa cells. For the molecular mechanisms, P2 was shown to downregulate the gene expression of proinflammatory cytokines IL-6 and IL-8 and to inhibit the COX-2 and iNOS-related pathways in HeLa cells. In consequence, P2 might inhibit tumor development by blocking the interaction between tumor microenvironment and proinflammatory mediators. All findings indicate that P2 possesses the potential to be developed as a novel agent for cancer therapy.

Stearoyl-CoA desaturase plays an important role in proliferation and chemoresistance in human hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is often diagnosed at an advanced stage, when it is not amenable for aggressive therapies such as surgical resection or liver transplantation. Current therapeutic options achieve clinical responses in only a small percentage of cases. As a consequence, effective approaches for prevention and treatment are greatly needed. Altered lipid metabolism has been recently linked to HCC pathogenesis. The aims of this study were to define the cellular and molecular mechanisms linking stearoyl-CoA desaturase (SCD), the rate-limiting enzyme and an essential regulator of lipid homeostasis in liver cells, to carcinogenesis in HCC.

MATERIAL AND METHODS

HCC and normal liver specimens were collected. Human HCC cell lines: HepG2, Hep3B, and PLC/PLF/5 were used for immunoblot, cell viability, proliferation, and apoptosis assays. Small interfering RNAs were used for genetic inhibition, and 10, 12 conjugated linoleic acid was used for pharmacologic SCD inhibition.

RESULTS

SCD was strongly expressed in surgically resected HCC (n = 64) and various human HCC cell lines (HepG2, Hep3B, and PLC/PLF/5). The levels of SCD negatively correlated with degree of tumor differentiation (P < 0.01). Treatment of these HCC cell lines with a panel of chemotherapeutic drugs resulted in a time-dependent, phosphatidylinositol 3 kinase- and c-Jun N-terminal kinases1/2-mediated upregulation of SCD expression, which paralleled the degree of resistance to drug-induced apoptosis. Specific genetic or pharmacologic SCD suppression resulted in inhibition of cell proliferation (P < 0.001) and significantly increased sensitivity to chemotherapy-induced apoptosis.

CONCLUSIONS

Our data suggest that increased SCD expression plays an important role in HCC development and resistance to chemotherapy-induced apoptosis, and this is in part mediated by phosphatidylinositol 3 kinase/c-Jun N-terminal kinases activation. Specific targeted interruption of this pathway in HCC could be a desirable approach in designing novel therapeutic strategies.

Proinflammatory conditions promote hepatocellular carcinoma onset and progression via activation of Wnt and EGFR signaling pathways

The aim of the current study was to investigate how proinflammatory conditions affect growth and progression of hepatocellular carcinoma. Human hepatoma cell lines were treated with lipopolysaccharide (LPS) or cyclooxygenase-2 inhibitor, Celecoxib, and in vitro proliferation, apoptosis, and cell cycle progression were assessed. This was followed up with in vivo xenograft assays to monitor tumor growth and metastatic progression under different treatment conditions. While LPS induced cell proliferation, Celecoxib induced apoptosis. Flow cytometry analysis demonstrated that S-phase cell count in LPS group was higher than control group (41.9 ± 3.2 vs 30.6 ± 0.1%, respectively), whereas G0/G1-phase cells were significantly higher in the Celecoxib group in comparison with the control group (69.6 ± 5.0 vs 50.4 ± 1.6%, respectively) (p < 0.05). Immunoblot analyses showed induction of epidermal growth factor receptor expression and induction and nuclear accumulation of Wnt/β-catenin and p65 in LPS group. Xenograft assays showed that LPS treatment induced comparatively large, rapidly growing tumors (2,702 ± 572 mm(3)) that metastasized to lungs, whereas Celecoxib treatment alone (1,008 ± 296 mm(3)) or in combination with LPS (1,303 ± 283 mm(3)) suppressed tumor growth in comparison to control groups (2,072 ± 456 mm(3)) (n = 5; p < 0.05). Inflammation can thus promote hepatoma cell proliferation and growth, and enhance the invasion and metastatic ability of hepatocarcinoma cells through inducing tumor angiogenesis, which in turn may be related to the activation of Wnt/β-catenin and EGFR signaling pathways.

Unexpected remission of hepatocellular carcinoma (HCC) with lung metastasis to the combination therapy of thalidomide and cyproheptadine: report of two cases and a preliminary HCC cell line study

We reported two cases of hepatocellular carcinoma (HCC) with lung metastases who were treated with a combination of thalidomide and cyproheptadine. The use of cyproheptadine in these two cases was originally for skin itching. Follow-up CT images revealed a complete remission of HCC in both of them after treatment for 6 months and 6 weeks, respectively. A following experimental cell line study demonstrated that cyproheptadine effectively reduced the viability of two HCC cell lines.

Proliferation of Hepatic Oval Cells via Cyclooxygenase-2 and Extracellular Matrix Protein Signaling during Liver Regeneration Following 2-AAF/Partial Hepatectomy in Rats

BACKGROUND/AIMS

In the 2-acetylaminofluorene (2-AAF)/70% partial hepatectomy (PHx) model, the mechanism underlying the differentiation of activated hepatic oval cells (HOCs) into hepatocytes and bile ductile cells is unclear. We investigated the role of cyclooxygenase-2 (COX-2) in HOCs and the relationship between COX-2 and extracellular matrix proteins in cellular proliferation.

METHODS

Reverse transcription-polymerase chain reaction, immunohistochemical staining, and Western blotting were used to assess COX-2 expression. The co-localization of COX-2 with Thy1, c-Met, epithelial cell adhesion molecule, and α-smooth muscle actin was also examined. Additionally, we investigated whether connective tissue growth factor (CTGF), fibronectin (FN), extracellular signal-regulated kinase 1/2 (P-ERK1/2), and AKT were expressed in HOCs.

RESULTS

The expression of COX-2, prostaglandin E2 receptors, and c-Met was upregulated in HOCs. However, HOCs treated with the COX-2 inhibitor NS398 showed decreased COX-2, CTGF, FN, and AKT expression, whereas P-ERK1/2 was unaffected. Additionally, NS398 inhibited HOC proliferation, but not the proliferation of HOCs cultured on FN-coated dishes. Furthermore, the proliferative response of HOCs treated with NS398 was reversed by hepatic growth factor treatment.

CONCLUSIONS

These results suggest that HOC proliferation is mediated through COX-2, extracellular FN expression, and AKT activation. Thus, COX-2 plays an important role in HOC proliferation following acute injury.

Non-genomic action of TCDD to induce inflammatory responses in HepG2 human hepatoma cells and in liver of C57BL/6J mice

To assess the significance of the non-genomic signaling of TCDD (=dioxin) on liver of C57BL/6 mice and HepG2 human hepatoma cells, we first determined the group of markers that are susceptible to inhibition by parthenolide, a compound known to specifically suppress NF-κB-mediated inflammation. Of those, the most consistent marker turned out to be SOCS3 (a suppressor of cytokine signaling) known to respond to inflammation. An early diagnostic test on the action of TCDD on HepG2 cells in vitro within 3-6 h indicated that Cox-2 and SOCS3 are mainly induced via a non-genomic route, whereas PAI-2 appears to be induced through the classical action route. More detailed diagnostic tests at later stages of action of TCDD in HepG2 cells revealed that induction of IL-1β, BAFF, and iNOS are largely mediated by the protein kinase-dependent non-genomic route. An in vivo study on the 7 day action of TCDD on liver of AhR(NLS) mice showed that several early markers (e.g., Cox-2, MCP-1 and SOCS3) are induced, but not late markers such as IL-1β. Together, these results show that the non-genomic pathway contributes significantly to the early stress response reactions to TCDD that includes inflammation in hepatoma cells as well as in the liver.

Cyclooxygenase-2 inhibitor blocks the production of West Nile virus-induced neuroinflammatory markers in astrocytes

Inflammatory immune responses triggered initially to clear West Nile virus (WNV) infection later become detrimental and contribute to the pathological processes such as blood–brain barrier (BBB) disruption and neuronal death, thus complicating WNV-associated encephalitis (WNVE). It has been demonstrated previously that WNV infection in astrocytes results in induction of multiple matrix metalloproteinases (MMPs), which mediate BBB disruption. Cyclooxygenase (COX) enzymes and their product, prostaglandin E2 (PGE2), modulate neuroinflammation and regulate the production of multiple inflammatory molecules including MMPs. Therefore, this study determined and characterized the pathophysiological consequences of the expression of COX enzymes in human brain cortical astrocytes (HBCAs) following WNV infection. Whilst COX-1 mRNA expression did not change, WNV infection significantly induced RNA and protein expression of COX-2 in HBCAs. Similarly, PGE2 production was also enhanced significantly in infected HBCAs and was blocked in the presence of the COX-2-specific inhibitor NS-398, thus suggesting that COX-2, and not COX-1, was the source of the increased PGE2. Treatment of infected HBCAs with NS-398 attenuated the expression of MMP-1, -3 and -9 in a dose-dependent manner. Similarly, expression of interleukin-1β, -6 and -8, which were markedly elevated in infected HBCAs, exhibited a significant reduction in their levels in the presence of NS-398. These results provide direct evidence that WNV-induced COX-2/PGE2 is involved in modulating the expression of multiple neuroinflammatory mediators, thereby directly linking COX-2 with WNV disease pathogenesis. The ability of COX-2 inhibitors to modulate WNV-induced COX-2 and PGE2 signalling warrants further investigation in an animal model as a potential approach for clinical management of neuroinflammation associated with WNVE.

Transcript profiling identifies novel key players mediating the growth inhibitory effect of NS-398 on human pancreatic cancer cells

Pancreatic cancer is one of the most aggressive human malignancies with an increasing incidence worldwide. Despite an increase in the number of systemic treatments available for pancreatic cancer, the impact of therapy on the clinical course of the disease has been modest, underscoring an urgent need for new therapeutic options. Although selective cyclooxygenase-2 inhibitors have been demonstrated to have cancer-preventive effects, the mechanism of their effects is not clearly known. Moreover, there have been no unbiased studies to identify novel molecular targets of NS-398 regarding pancreatic cancer. Here we undertook a gene expression profiling study to identify novel molecular targets modulating the growth inhibitory effects of NS-398 on pancreatic cancer cell lines. Our mRNA-based gene expression results showed that the growth inhibitory effect of NS-398 was accompanied with an activation of G1/S and G2/M cell cycle regulation, P53 signalling, apoptotic, aryl hydrocarbon receptor and death receptor signalling pathways. Moreover, we reported, for the first time, that the growth inhibitory effect of NS-398 is mediated by down-regulation of RRM2, CTGF, MCM2 and PCNA and up-regulation of NAG-1 in all cell lines.

CIDE-3 interacts with lipopolysaccharide-induced tumor necrosis factor, and overexpression increases apoptosis in hepatocellular carcinoma

Cell death-inducing DFF45-like effector-3 (CIDE-3) is a novel member of an apoptosis-inducing protein family, but its function is unknown. CIDE-3 shows a different distribution pattern in hepatocellular carcinoma (HCC) tissues and normal adjacent tissues. Therefore, this work tested the hypothesis that CIDE-3 induces apoptosis in HCC cells, inhibiting oncogenesis and tumor development. We used immunohistochemistry to evaluate the expression of CIDE-3 in 82 HCC samples and 51 adjacent liver tissues. Overexpression of CIDE-3 induced apoptosis, as detected by flow cytometry, in the HCC cell line SMMC-7721, which had undetectable levels of CIDE-3 in the absence of CIDE-3 overexpression. A yeast two-hybrid system was employed to screen for proteins that interact with CIDE-3. The expression of CIDE-3 was decreased in HCC tissue, compared to adjacent normal tissues, and CIDE-3 expression and HCC differentiation were positively correlated. CIDE-3 expression levels were lower in poorly differentiated HCC tissue than in well-differentiated HCC tissue. Overexpressed CIDE-3 inhibited proliferation and induced apoptosis in HCC cells. We found that lipopolysaccharide-induced tumor necrosis factor (LITAF) interacted with CIDE-3 in hepatic cells. This is the first demonstrated interaction between CIDE-3 and LITAF, and the first report that CIDE-3 induces apoptosis in hepatocellular carcinoma.

Large-scale analysis of network bistability for human cancers

Protein-protein interaction and gene regulatory networks are likely to be locked in a state corresponding to a disease by the behavior of one or more bistable circuits exhibiting switch-like behavior. Sets of genes could be over-expressed or repressed when anomalies due to disease appear, and the circuits responsible for this over- or under-expression might persist for as long as the disease state continues. This paper shows how a large-scale analysis of network bistability for various human cancers can identify genes that can potentially serve as drug targets or diagnosis biomarkers.

Celecoxib inhibits the expression of MMP-2 and ICAM-1 in hepatocellular carcinoma xenografts in nude mice

AIM: To investigate the antitumor effects of celecoxib (a selective cyclooxygenase-2 inhibitor) against hepatocellular carcinoma in vivo.

METHODS: Human hepatoma cells (HepG2, BEL-7402 and SMMC-7721) were injected beneath the hepatic capsule of six-week-old nude mice. The mice were then randomly divided into three groups: negative control group (intragastrically given normal saline), experimental group (intragastrically given celecoxib), and positive control group (intragastrically given normal saline and intraperitoneally injected with adriamycin). Three weeks later, tumor tissue samples were taken for immunohistochemical analysis to examine the expression of matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinases-2 (TIMP-2) and intercellular adhesion molecule-1 (ICAM-1).

RESULTS: Compared to the negative control group, the expression of MMP-2 was down-regulated (P < 0.05) and that of TIMP-2 was up-regulated (P < 0.05) in hepatocellular carcinoma xenografts derived from HepG2, BEL-7402 and SMMC-7721 cells in the experimental group. The expression of ICAM-1 was also down-regulated in hepatocellular carcinoma xenografts derived from BEL-7402 and SMMC-7721 cells in the experimental group when compared with the negative control group (P < 0.05).

CONCLUSION: Celecoxib may be able to inhibit the metastasis and improve the prognosis of hepatocellular carcinoma.

Negative impact of neutrophil-lymphocyte ratio on outcome after liver transplantation for hepatocellular carcinoma

BACKGROUND

The Milan criteria have been adopted by United Network for Organ Sharing (UNOS) to preoperatively assess outcome in patients with hepatocellular carcinoma (HCC) who receive orthotopic liver transplantation (OLT). These criteria rely solely on radiographic appearances of the tumor, providing no measure of tumor biology. Recurrence rates, therefore, remain around 20% for patients within the criteria. The neutrophil-lymphocyte ratio (NLR) is an indicator of inflammatory status previously established as a prognostic indicator in colorectal liver metastases. We aimed to determine whether NLR predicts outcome in patients undergoing OLT for HCC.

DESIGN

Analysis of patients undergoing OLT for HCC between 2001 and 2007 at our institution. A NLR > or =5 was considered to be elevated.

RESULTS

: A total of 150 patients were identified, with 13 patients having an elevated NLR. Of these, 62% developed recurrence compared with 14% with normal NLR (P < 0.0001). The disease-free survival for patients with high NLR was significantly worse than that for patients with normal NLR (1-, 3-, and 5-year survivals of 38%, 25%, and 25% vs. 92%, 85%, and 75%, P < 0.0001). Patients with high NLR also had poorer overall survival (5-year survival, 28% vs. 64%, P = 0.001). Patients within Milan with an elevated NLR had significantly poorer disease-free survival than those with normal NLR within Milan (5-year survival, 30% vs. 81%, P < 0.0001). On univariate analysis, 9 factors including an NLR > or =5 were significant predictors of poor disease-free survival. However, only a raised NLR remained significant on multivariate analysis (P = 0.005, HR: 19.98).

CONCLUSION

Elevated NLR significantly increases the risk for tumor recurrence and recipient death. Preoperative NLR measurement may provide a simple method of identifying patients with poorer prognosis and act as an adjunct to Milan in determining, which patients benefit most from OLT.

Effects of Celecoxib and Nimesulide on the Proliferation of Ectopic Endometrial Stromal Cells in vitro

The effects of cyclooxygenase 2 (COX-2) selective inhibitors on the proliferation of ectopic endometrial stromal cells in vitro were investigated. Ectopic endometrial stromal cells were treated with either celecoxib or nimesulide for 24 and 48 h. The results showed that (i) both celecoxib and nimesulide inhibited the proliferation of ectopic endometrial stromal cells in vitro in a time- and dose-dependent manner; (ii) the expression of prostaglandin E2 was significantly inhibited by both celecoxib and nimesulide in a dose-dependent manner; (iii) the percentage of apoptotic cells was significantly higher for cells treated with celecoxib or nimesulide than for untreated cells; and (iv) the percentage of the cells in the G0/G1 phase increased after the cells were treated with either agent in a dose-dependent manner. These data suggest that celecoxib and nimesulide inhibited proliferation of ectopic endometrial stromal cells by inducing apoptosis and blocking the cell cycle at the G0/G1 phase.