Morihisa Hirota

Expression of survivin is correlated with cancer cell apoptosis and is involved in the development of human pancreatic duct cell tumors

Survivin is a new member of the inhibitor of apoptosis family of antiapoptotic proteins. This protein was expressed selectively in all the most common human carcinomas but not in normal adult tissues. To our knowledge, the relation between survivin expression and apoptosis or tumorigenesis has not yet been studied in pancreatic neoplasms.

Hypoxia stimulates pancreatic stellate cells to induce fibrosis and angiogenesis in pancreatic cancer

Pancreatic cancer is characterized by excessive desmoplastic reaction and by a hypoxic microenvironment within the solid tumor mass. Chronic pancreatitis is also characterized by fibrosis and hypoxia. Fibroblasts in the area of fibrosis in these pathological settings are now recognized as activated pancreatic stellate cells (PSCs). Recent studies have suggested that a hypoxic environment concomitantly exists not only in pancreatic cancer cells but also in surrounding PSCs. This study aimed to clarify whether hypoxia affected the cell functions in PSCs. Human PSCs were isolated and cultured under normoxia (21% O(2)) or hypoxia (1% O(2)). We examined the effects of hypoxia and conditioned media of hypoxia-treated PSCs on cell functions in PSCs and in human umbilical vein endothelial cells. Hypoxia induced migration, type I collagen expression, and vascular endothelial growth factor (VEGF) production in PSCs. Conditioned media of hypoxia-treated PSCs induced migration of PSCs, which was inhibited by anti-VEGF antibody but not by antibody against hepatocyte growth factor. Conditioned media of hypoxia-treated PSCs induced endothelial cell proliferation, migration, and angiogenesis in vitro and in vivo. PSCs expressed several angiogenesis-regulating molecules including VEGF receptors, angiopoietin-1, and Tie-2. In conclusion, hypoxia induced profibrogenic and proangiogenic responses in PSCs. In addition to their established profibrogenic roles, PSCs might play proangiogenic roles during the development of pancreatic fibrosis, where they are subjected to hypoxia.

MiR-126 acts as a tumor suppressor in pancreatic cancer cells via the regulation of ADAM9.

The epithelial-mesenchymal transition (EMT) is a critical step for pancreatic cancer cells as an entry of metastatic disease. Wide variety of cytokines and signaling pathways are involved in this complex process while the entire picture is still cryptic. Recently, miRNA was found to regulate cellular function including EMT by targeting multiple mRNAs. We conducted comprehensive analysis of miRNA expression profiles in invasive ductal adenocarcinoma (IDA), intraductal papillary mucinous adenoma, intraductal papillary mucinous carcinoma, and human pancreatic cancer cell line to elucidate essential miRNAs which regulate invasive growth of pancreatic cancer cells. Along with higher expression of miR-21 which has been shown to be highly expressed in IDA, reduced expression of miR-126 in IDA and pancreatic cancer cell line was detected. The miR-126 was found to target ADAM9 (disintegrin and metalloproteinase domain-containing protein 9) which is highly expressed in pancreatic cancer. The direct interaction between miR-126 and ADAM9 mRNA was confirmed by 3′ untranslated region assay. Reexpression of miR-126 and siRNA-based knockdown of ADAM9 in pancreatic cancer cells resulted in reduced cellular migration, invasion, and induction of epithelial marker E-cadherin. We showed for the first time that the miR-126/ADAM9 axis plays essential role in the inhibition of invasive growth of pancreatic cancer cells. Mol Cancer Res; 10(1); 3–10. ©2011 AACR.

Nationwide epidemiological survey of autoimmune pancreatitis in Japan.

Objectives To clarify the clinicoepidemiological features of autoimmune pancreatitis (AIP) in Japan, the nationwide survey was conducted. Methods Patients with AIP who had visited the selected hospitals in 2007 were surveyed. Autoimmune pancreatitis was diagnosed according to the Japanese clinical diagnostic criteria 2006. The study consisted of 2-stage surveys: the number of patients with AIP was estimated by the first questionnaire and their clinical features were assessed by the second questionnaire. Results The estimated total number of AIP patients in 2007 was 2790 (95% confidence interval, 2540–3040), with an overall prevalence rate of 2.2 per 100,000 populations. The number of patients, who were newly diagnosed as AIP, was estimated to be 1120 (95% confidence interval, 1000–1240), with an annual incidence rate of 0.9 per 100,000 populations. Sex ratio (male to female) was 3.7, and the mean (SD) age was 63.0 (11.4) years. Among the 546 patients whose clinical information was obtained, 87.6% of the patients presented high serum immunoglobulin G4 levels (≥135 mg/dL), and 83% received steroid therapy. Conclusions The data represent the current clinical features of AIP in Japan. From the results, most AIP patients in Japan can be categorized to type 1 AIP according to the recent classification of AIP. Abbreviations AIP - autoimmune pancreatitis CI - confidence interval IgG - immunoglobulin G MPD - main pancreatic duct

Periostin, secreted from stromal cells, has biphasic effect on cell migration and correlates with the epithelial to mesenchymal transition of human pancreatic cancer cells

Periostin is a secretory protein that has been suggested to function as a cell adhesion molecule and promote the invasiveness or growth rate of tumors. However, little is known about the association of its expression and epithelial to mesenchymal transition (EMT), which is considered to play a crucial role in cancer cell metastasis. Thus, the authors investigated whether periostin could be involved in the process of EMT and the role of this gene in pancreatic cancer development. The expression of periostin was observed mainly in stromal cells but very little in cancer cells by immunohistochemistry and real‐time RT‐PCR. In vitro, pancreatic stellate cells (PSCs) exhibited a much higher basal expression of periostin compared with cancer cells. Periostin secreted in the supernatant from 293T cells that expressed periostin (approximately 150 ng/ml) inhibited the migration of pancreatic cancer cells. Coculture assay revealed that periostin expression in PSC was induced by pancreatic cancer cells. To assess the direct role of periostin in pancreatic cancer cells, the authors generated pancreatic cancer cell lines that stably express periostin. The induced expression of periostin (to 150 ng/ml) altered the morphology of cancer cells, changing them from mesenchymal to epithelial phenotypes with the induction of epithelial markers and a reduction of mesenchymal markers, and showed reduced cell migration in vitro and formed smaller tumors as well as suppressed metastasis in vivo. On the other hand, high concentration of recombinant periostin (1 μg/ml) promoted cell migration with AKT activation. The findings suggest that periostin has biphasic effect on the development of pancreatic cancer.

Japanese guidelines for the management of acute pancreatitis: Japanese Guidelines 2015.

Japanese (JPN) guidelines for the management of acute pancreatitis were published in 2006. The severity assessment criteria for acute pancreatitis were later revised by the Japanese Ministry of Health, Labour and Welfare (MHLW) in 2008, leading to their publication as the JPN Guidelines 2010. Following the 2012 revision of the Atlanta Classifications of Acute Pancreatitis, in which the classifications of regional complications of pancreatitis were revised, the development of a minimally invasive method for local complications of pancreatitis spread, and emerging evidence was gathered and revised into the JPN Guidelines.

The revised Japanese clinical diagnostic criteria for chronic pancreatitis

In Japan, we are now using the clinical diagnostic criteria for chronic pancreatitis (CP) that were revised in 2001 to add the findings of magnetic resonance cholangiopancreatography to the criteria compiled by the Japan Pancreas Society (JPS) in 1995. Because the current criteria are set for diagnosing advanced CP, they are unlikely to improve patients’ prognoses. In addition, they seem unsuitable for current clinical practice because exocrine pancreatic function tests, which have become obsolete in Japan, are included in the diagnostic factors. For these reasons, the Research Committee on Intractable Pancreatic Diseases supported by the Ministry of Health, Labour and Welfare of Japan, the JPS and the Japanese Society of Gastroenterology have revised the criteria. The revised criteria are unique in that they contain an introduction to the concept of early CP. It is a challenge aimed at improvement of the long-term prognosis of CP patients by early diagnosis and therapeutic intervention in this disease. We need to determine and clarify the clinico-pathological outcome of early CP by a prospective long-term follow-up of the patients in this category.

Fibrinogen induces cytokine and collagen production in pancreatic stellate cells

Objective: Fibroblasts in the area of fibrosis in chronic pancreatitis and of the desmoplastic reaction associated with pancreatic cancer are now recognised as activated pancreatic stellate cells (PSCs). Recent studies have shown strong expression of fibrinogen, the central protein in the haemostasis pathway, in the stromal tissues of pancreatic cancer and chronic pancreatitis, suggesting that PSCs are embedded in and exposed to abundant fibrinogen in these pathological settings. The effects of fibrinogen on cell functions in PSCs were examined here. Methods: PSCs were isolated from human pancreas tissues of patients undergoing operations for pancreatic cancer, and from rat pancreatic tissues. The effects of fibrinogen on key cell functions and activation of signalling pathways in PSCs were examined. Results: Fibrinogen induced the production of interleukin 6 (IL6), interleukin 8 (IL8), monocyte chemoattractant protein-1, vascular endothelial growth factor, angiopoietin-1 and type I collagen, but not proliferation or intercellular adhesion molecule-1 expression. Fibrinogen increased α-smooth muscle actin expression and induced the activation of nuclear factor-κB (NF-κB), Akt and three classes of mitogen-activated protein kinases (extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase and p38 mitogen-activated protein kinase (MAPK)). Fibrinogen-induced IL6 and IL8 production was inhibited by antibodies against αvβ3 and α5β1 integrins, suggesting that these integrins worked as counter receptors for fibrinogen in PSCs. In addition, fibrinogen-induced production of these cytokines was abolished by an inhibitor of NF-κB, and partially inhibited by inhibitors of ERK and p38 MAPK. Conclusion: Fibrinogen directly stimulated profibrogenic and proinflammatory functions in PSCs.

Bone morphogenetic protein 4 induces epithelial-mesenchymal transition through MSX2 induction on pancreatic cancer cell line.

In our study, we found that bone morphogenetic protein 4 (BMP4) has a novel effect as an inducer of epithelial‐mesenchymal transition (EMT) on Panc‐1 cells, a human pancreatic carcinoma cell line. BMP4‐treated Panc‐1 cells showed loose cell contacts and a scattered, fibroblast‐like appearance along with E‐cadherin downregulation, Vimentin upregulation and enhanced cell migration, which are characteristic of EMT. BMP4 treatment also induced homeobox gene MSX2 expression, which we previously showed to be associated with EMT in pancreatic carcinoma cells. BMP4 treatment activated the Smad signaling pathway, and extracellular signal‐related kinase (ERK) and p38 mitogen‐activated kinase (MAPK) pathways in these cells. MSX2 was markedly induced by BMP4 through the ERK and p38 MAPK pathways in collaboration with the Smad signaling pathway. The repression of E‐cadherin, induction of Vimentin and enhanced cell migration disappeared when siRNA‐based MSX2 downregulated pancreatic cancer cells were treated with BMP4. These findings indicate that BMP4 may be involved in pancreatic carcinoma development through the promotion of EMT and that MSX2 is indispensable to this process. J. Cell. Physiol. 213:768–774.

Diagnosis of autoimmune pancreatitis by EUS-FNA by using a 22-gauge needle based on the International Consensus Diagnostic Criteria

BACKGROUND It is controversial whether EUS-guided FNA by using 22-gauge (G) needles is useful for the diagnosis or evaluation of autoimmune pancreatitis (AIP). OBJECTIVE To evaluate the usefulness of EUS-FNA by 22-G needles for the histopathological diagnosis of AIP. DESIGN A retrospective study. SETTING Single academic center. PATIENTS A total of 273 patients, including 25 with AIP, underwent EUS-FNA and histological examinations. RESULTS EUS-FNA by using 22-G needles provided adequate tissue samples for histopathological evaluation because more than 10 high-power fields were available for evaluation in 20 of 25 patients (80%). The mean immunoglobulin G4-positive plasma cell count was 13.7/high-power field. Obliterative phlebitis was observed in 10 of 25 patients (40%). In the context of the International Consensus Diagnostic Criteria for AIP, 14 and 6 of 25 patients were judged to have level 1 (positive for 3 or 4 items) and level 2 (positive for 2 items) histological findings, respectively, meaning that 20 of 25 patients were suggested to have lymphoplasmacytic sclerosing pancreatitis based on the International Consensus Diagnostic Criteria. The diagnosis in 1 patient was type 2 AIP because a granulocytic epithelial lesion was identified in this patient. LIMITATIONS A retrospective study with a small number of patients. CONCLUSIONS The results of this study suggest that EUS-FNA by using 22-G needles provides tissue samples adequate for histopathological evaluation and greatly contributes to the histological diagnosis of AIP.