Crohn's disease (CD) is routinely evaluated using clinical symptoms, laboratory variables, and the CD activity index (CDAI). However, clinical parameters are often nonspecific and do not precisely reflect the actual activity of CD small-intestinal lesions. The purposes of this prospective study were to compare color Doppler ultrasound (US) findings with histological findings from surgically resected specimens and confirm the hypothesis that color Doppler US can distinguish tissue inflammation and fibrosis.
E-cadherin is an important adhesion molecule whose loss is associated with progression and poor prognosis of liver cancer. However, it is unclear whether the loss of E-cadherin is a real culprit or a bystander in liver cancer progression. In addition, the precise role of E-cadherin in maintaining liver homeostasis is also still unknown, especially in vivo. Here we demonstrate that liver-specific E-cadherin knockout mice develop spontaneous periportal inflammation via an impaired intrahepatic biliary network, as well as periductal fibrosis, which resembles primary sclerosing cholangitis. Inducible gene knockout studies identified E-cadherin loss in biliary epithelial cells as a causal factor of cholangitis induction. Furthermore, a few of the E-cadherin knockout mice developed spontaneous liver cancer. When knockout of E-cadherin is combined with Ras activation or chemical carcinogen administration, E-cadherin knockout mice display markedly accelerated carcinogenesis and an invasive phenotype associated with epithelial-mesenchymal transition, up-regulation of stem cell markers, and elevated ERK activation. Also in human hepatocellular carcinoma, E-cadherin loss correlates with increased expression of mesenchymal and stem cell markers, and silencing of E-cadherin in hepatocellular carcinoma cell lines causes epithelial-mesenchymal transition and increased invasiveness, suggesting that E-cadherin loss can be a causal factor of these phenotypes. Thus, E-cadherin plays critical roles in maintaining homeostasis and suppressing carcinogenesis in the liver.
Abstract Objective. Ultrasonography (US) is a simple, inexpensive and minimally invasive method. We evaluated the vascularity of small intestinal lesions in Crohns disease using color Doppler US (CD-US) and retrospectively compared them with endoscopic and surgical macroscopic findings. Material and methods. In order to compare CD-US and endoscopic findings, 108 Crohns disease patients who underwent examination of the terminal ileum by both colonoscopy and CD-US were included in the study. Vascularity was evaluated in CD-US using a semiquantitative method, the Limberg score. We analyzed correlations between Limberg score and simple endoscopic score for Crohns disease (SES-CD), an index reflecting endoscopic activity. Scores of SES-CD 3 and higher were defined as endoscopically active. For comparison with surgical macroscopic findings, 22 Crohns disease patients who received CD-US and subsequent iliectomies were included. Lesions with apparent open ulcers were defined as active, and those without as non-active. These findings were compared with the Limberg score. Results. A substantial positive correlation was observed between Limberg scores and SES-CD (? = 0.709 [p < 0.001]). Notably, all 27 cases with a Limberg score of 3 or 4 were classified as endoscopically active. Compared to surgical macroscopic activity, Limberg scores of active lesions were significantly higher than those of non-active lesions (p = 0.005). In particular, all 11 cases with a Limberg score of 3 or 4 were classified as active lesions. Conclusion. Vascularity of small intestinal lesions of Crohns disease evaluated by CD-US with Limberg score is well correlated with endoscopic and surgical macroscopic findings.
The mitogen-activated protein kinase (MAPK) signaling pathway regulates various cellular functions, including those induced by Helicobacter pylori. TAK1 is an upstream MAPK kinase kinase (MAP3K) required for H. pylori-induced MAPK and NF-?B activation, but it remains unclear whether other MAP3Ks are involved in H. pylori-induced cellular responses. In this study, we focused on the MAP3K ASK1, which plays a critical role in gastric tumorigenesis. In gastric epithelial cells, H. pylori activates ASK1 in a reactive oxygen species (ROS)- and cag pathogenicity island-dependent manner, and ASK1 regulates sustained JNK activation and apoptosis induced by H. pylori. In contrast, TAK1 regulates H. pylori-mediated early JNK activation and cytokine production. We also found reciprocal regulation between ASK1 and TAK1 in H. pylori-related responses, whereby inhibition of TAK1 or downstream p38 MAPK activates ASK1 through ROS production, and ASK1 suppresses TAK1 and downstream NF-?B activation. We identified ROS/ASK1/JNK as a new signaling pathway induced by H. pylori, which regulates apoptotic cell death. The balance of ASK1-induced apoptosis and TAK1-induced antiapoptotic or inflammatory responses may determine the fate of epithelial cells infected with H. pylori and thus be involved in the pathogenesis of gastritis and gastric cancer.
c-Jun N-terminal kinase (JNK) is a member of the mitogen-activated protein kinase (MAPK) family, and it is reportedly involved in the development of several cancers. However, the role of JNK in pancreatic cancer has not been elucidated. We assessed t he involvement of JNK in the development of pancreatic cancer and investigated the therapeutic effect of JNK inhibitors on this deadly cancer. Small interfering RNAs against JNK or the JNK inhibitor SP600125 were used to examine the role of JNK in cellular proliferation and the cell cycles of pancreatic cancer cell lines. Ptf1a(cre/+) ;LSL-Kras(G12D/+) ;Tgfbr2(flox/flox) mice were treated with the JNK inhibitor to examine pancreatic histology and survival. The effect of JNK inhibition on tumor angiogenesis was also assessed using cell lines and murine pancreatic cancer specimens. JNK was frequently activated in human and murine pancreatic cancer in vitro and in vivo. Growth of human pancreatic cancer cell lines was suppressed by JNK inhibition through G1 arrest in the cell cycle with decreased cyclin D1 expression. In addition, oncogenic K-ras expression led to activation of JNK in pancreatic cancer cell lines. Treatment of Ptf1a(cre/+) ;LSL-Kras(G12D/+) ;Tgfbr2(flox/flox) mice with the JNK inhibitor decreased growth of murine pancreatic cancer and prolonged survival of the mice significantly. Angiogenesis was also decreased by JNK inhibition in vitro and in vivo. In conclusion, activation of JNK promotes development of pancreatic cancer, and JNK may be a potential therapeutic target for pancreatic cancer.
Interleukin-6 (IL-6) is a pleiotropic cytokine that affects various functions, including tumor development. Although the importance of IL-6 in gastric cancer has been documented in experimental and clinical studies, the mechanism by which IL-6 promotes gastric cancer remains unclear. In this study, we investigated the role of IL-6 in the epithelial-stromal interaction in gastric tumorigenesis. Immunohistochemical analysis of human gastritis, gastric adenoma, and gastric cancer tissues revealed that IL-6 was frequently detected in the stroma. IL-6-positive cells in the stroma showed positive staining for the fibroblast marker ?-smooth muscle actin, suggesting that stromal fibroblasts produce IL-6. We compared IL-6 knockout (IL-6(-/-)) mice with wild-type (WT) mice in a model of gastric tumorigenesis induced by the chemical carcinogen N-methyl-N-nitrosourea. The stromal fibroblasts expressed IL-6 in tumors from WT mice. Gastric tumorigenesis was attenuated in IL-6(-/-) mice, compared with WT mice. Impaired tumor development in IL-6(-/-) mice was correlated with the decreased activation of STAT3, a factor associated with gastric cancer cell proliferation. In vitro, when gastric cancer cell line was co-cultured with primary human gastric fibroblast, STAT3-related genes including COX-2 and iNOS were induced in gastric cancer cells and this response was attenuated with neutralizing anti-IL-6 receptor antibody. IL-6 production from fibroblasts was increased when fibroblasts were cultured in the presence of gastric cancer cell-conditioned media. IL-6 production from fibroblasts was suppressed by an interleukin-1 (IL-1) receptor antagonist and siRNA inhibition of IL-1? in the fibroblasts. IL-1? mRNA and protein were increased in fibroblast lysate, suggesting that cell-associated IL-1? in fibroblasts may be involved. Our results suggest the importance of IL-6 mediated stromal-epithelial cell interaction in gastric tumorigenesis.
The prognosis of unresectable advanced gastric cancer has improved over the last decade due to advances in chemotherapy. However, molecular targeting in gastric cancer therapy has been poorly established and the 5?year survival rate is still <10%. The proteasome plays a pivotal role in the regulation of cell proliferation, apoptosis and differentiation in a variety of tumor cells. Bortezomib, a selective inhibitor of the proteasome, has prominent effects against several tumor types, including multiple myeloma. We examined the anti-tumor effects of bortezomib on gastric cancer cells in vitro and in subcutaneously transplanted nude mice. We demonstrated that among seven types of gastric cancer cells examined, treatment with bortezomib induced both apoptotic and anti-proliferative effects, resulting in a reduction in cell survival rates. The induction of apoptosis was observed to be dependent on the inhibition of nuclear factor ?B (NF-?B) activation and the subsequent production of reactive oxygen species (ROS) and c-Jun N-terminal kinase (JNK) activation. Interestingly, we observed that those cells with high levels of NF-?B activity were resistant to bortezomib treatment. Additionally, we demonstrated that the activation of the extracellular signal-regulated kinase (ERK1/2) was inhibited following bortezomib treatment, which may contribute to its anti-proliferative effects. We also observed anti?tumor effects of bortezomib in vivo. Bortezomib is a potential novel molecular targeting drug for the treatment of unresectable advanced gastric cancer.
The stress-activated mitogen-activated protein kinases (MAPKs), c-Jun NH2-terminal kinase (JNK), and p38 have been implicated in hepatocarcinogenesis. Although the many interrelated functions of JNK and p38 are precisely regulated by upstream signaling molecules, little is known about upstream regulators. We investigated the role of apoptosis signal-regulating kinase 1 (ASK1), a major player in the regulation of JNK and p38 activities, in hepatocarcinogenesis using a mouse hepatocellular carcinoma (HCC) model. ASK1-deficient (ASK1(-/-) ) and wildtype (WT) mice were treated with diethylnitrosamine on postnatal day 14. Strikingly, after 7 months, approximately three times as many tumors developed in ASK1(-/-) mice as in WT mice. Although JNK and p38 activation were attenuated in ASK1(-/-) HCCs relative to WT HCCs, cell proliferation was comparable in HCCs from both types of mice. On the other hand, both cancer cell apoptosis and hyperphosphorylation of BimEL, a proapoptotic Bcl-2 family member, were suppressed in the ASK1(-/-) HCCs. ASK1(-/-) mice showed remarkable resistance to Fas-induced hepatocyte apoptosis in vivo, probably because of attenuated JNK-mediated BimEL phosphorylation and mitochondrial apoptotic pathway activation. The reintroduction of ASK1 to ASK1(-/-) mouse liver using an adenoviral vector restored Fas-induced hepatocyte death and phosphorylation of JNK and BimEL. Similar findings were obtained in tumor necrosis factor alpha-induced hepatocyte apoptosis. Furthermore, ASK1 was involved in DNA damage-induced p21 up-regulation through a p38 pathway.
Mitogen-activated protein kinase (MAPK) pathways regulate multiple cellular functions and are highly active in many types of human cancers. Apoptosis signal-regulating kinase 1 (ASK1) is an upstream MAPK involved in apoptosis, inflammation, and carcinogenesis. This study investigated the role of ASK1 in the development of gastric cancer. In human gastric cancer specimens, we observed increased ASK1 expression, compared to nontumor epithelium. Using a chemically induced murine gastric tumorigenesis model, we observed increased tumor ASK1 expression, and ASK1 knockout mice had both fewer and smaller tumors than wild-type (WT) mice. ASK1 siRNA inhibited cell proliferation through the accumulation of cells in G1 phase of the cell cycle, and reduced cyclin D1 expression in gastric cancer cells, whereas these effects were uncommon in other cancer cells. ASK1 overexpression induced the transcription of cyclin D1, through AP-1 activation, and ASK1 levels were regulated by cyclin D1, via the Rb-E2F pathway. Exogenous ASK1 induced cyclin D1 expression, followed by elevated expression of endogenous ASK1. These results indicate an autoregulatory mechanism of ASK1 in the development of gastric cancer. Targeting this positive feedback loop, ASK1 may present a potential therapeutic target for the treatment of advanced gastric cancer.
Complete resection for colorectal metastases is the only treatment that can provide long-term survival and may lead to cure. Recent reports have shown that liver resection following systemic chemotherapy in patients with initially unresectable metastases from colorectal cancer may also result in a good long-term survival, and rescue surgery after chemotherapy has become a strategy of choice. A 29-year-old male and a 35-year-old female with unresectable liver metastases from colorectal cancer underwent complete resection after administration of third-line combination therapy of cetuximab and irinotecan. Although systemic chemotherapy may decrease liver function, which may make liver resection unfeasible, in the two cases reported, liver function did not deteriorate after cetuximab plus irinotecan. The indocyanine green retention rate at 15 minutes, which is useful in deciding the safe limit of hepatectomy, was optimal after the administration of cetuximab plus irinotecan in both patients. Cetuximab plus irinotecan may be beneficial as neoadjuvant chemotherapy for metastatic colorectal cancer, not only because of its oncological efficacy but also for preservation of liver function.
Interleukin-6 (IL-6) may play a role in the pathogenesis of hepatocellular carcinoma (HCC). Recently, it was reported in mouse models that estrogen-mediated inhibition of IL-6 production explains the gender disparity in HCC. We conducted a retrospective cohort study to examine whether this hypothesis is applicable to human HCC. We enrolled 330 patients with chronic hepatitis C whose serum samples were collected between January 1994 and December 2002. Serum IL-6 concentrations were measured and patients were divided into three groups according to IL-6 levels: low, middle, and high. We evaluated the association between serum IL-6 levels and the risk of subsequent HCC development, including subgroup analysis on each gender. During the follow-up period (mean 9.0 yr), HCC developed in 126 patients. The incidence rates differed significantly among the three groups (p = 0.015), increasing in accordance with serum IL-6 levels. However, unexpectedly, this tendency was significant only in female patients. In a multivariate analysis, higher serum IL-6 level was an independent risk factor for HCC development in female patients, with a hazard ratio of 1.61. Although female patients showed a weak negative correlation between serum IL-6 levels and estradiol levels, the lower risk of HCC in female patients cannot be fully explained by estrogen-mediated inhibition of IL-6 production. In conclusion, higher serum IL-6 level was an independent risk factor for HCC development in female but not male chronic hepatitis C patients. Measurement of serum IL-6 levels may provide useful information for predicting future HCC development in female chronic hepatitis C patients.
Aside from the human epidermal growth factor receptor-2 (HER2)-targeting agent trastuzumab, molecular targeting therapy for gastric cancer (GC) has not been established. We previously reported that apoptosis signal-regulating kinase-1 (ASK1) was upregulated in human GC and that overexpression of ASK1 promoted GC cell proliferation. Here, we investigated the effect of ASK1 inhibitor K811 on GC cells. K811 efficiently prevented cell proliferation in cell lines with high ASK1 expression and in HER2-overexpressing GC cells. Treatment with K811 reduced sizes of xenograft tumors by downregulating proliferation markers. These results indicate that ASK1 inhibition prevents GC cell growth in vitro and in vivo, suggesting that ASK1 inhibitors can be potent therapeutic drugs for GC.
Helicobacter pylori infection is associated with gastritis and gastric cancer. An H. pylori virulence factor, the cag pathogenicity island (PAI), is related to host cell cytokine induction and gastric inflammation. Since elucidation of the mechanisms of inflammation is important for therapy, the associations between cytokines and inflammatory diseases have been investigated vigorously. Levels of interleukin-32 (IL-32), a recently described inflammatory cytokine, are increased in various inflammatory diseases, such as rheumatoid arthritis and Crohns disease, and in malignancies, including gastric cancer. In this report, we examined IL-32 expression in human gastric disease. We also investigated the function of IL-32 in activation of the inflammatory cytokines in gastritis. IL-32 expression paralleled human gastric tissue pathology, with low IL-32 expression in H. pylori-uninfected gastric mucosa and higher expression levels in gastritis and gastric cancer tissues. H. pylori infection increased IL-32 expression in human gastric epithelial cell lines. H. pylori-induced IL-32 expression was dependent on the bacterial cagPAI genes and on activation of nuclear factor ?B (NF-?B). IL-32 expression induced by H. pylori was not detected in the supernatant of AGS cells but was found in the cytosol. Expression of the H. pylori-induced cytokines CXCL1, CXCL2, and IL-8 was decreased in IL-32-knockdown AGS cell lines compared to a control AGS cell line. We also found that NF-?B activation was decreased in H. pylori-infected IL-32-knockdown cells. These results suggest that IL-32 has important functions in the regulation of cytokine expression in H. pylori-infected gastric mucosa.
Mitochondrial isoenzyme of creatine kinase (MtCK) is reportedly highly expressed in hepatocellular carcinoma (HCC). Clinical relevance of serum MtCK activity in patients with HCC was assessed using a novel immuno-inhibition method.
Related JoVE Video
Journal of Visualized Experiments
What is Visualize?
JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.
How does it work?
We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.
Video X seems to be unrelated to Abstract Y...
In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.