Koji Amaya

Kanazawa University, Kanazawa, Ishikawa, Japan

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Publications (2)3.03 Total impact

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    ABSTRACT: Mass-forming pancreatitis can be divided into two distinct types: alcoholic and autoimmune. There have been some cases of an ambiguous diagnosis although care was taken to differentiate between alcoholic mass-forming pancreatitis, focal type autoimmune pancreatitis and pancreatic cancer. We report a case of pancreatic cancer mimicking alcoholic or autoimmune pancreatitis with the formation of a mass in a 32-year-old man with a history of heavy drinking. Although both serum immunoglobulin G and immunoglobulin G4 levels were normal, many serum auto-antibodies, including the antinuclear antibody, were detected. After he stopped drinking, abdominal computed tomography showed a pancreatic head mass 28 mm in diameter with little and weak enhancement in the early and delayed phases, respectively. Endoscopic retrograde cholangiopancreatography showed an obstruction of the main pancreatic duct in the pancreatic head and marked stenosis of the lower common bile duct. Although a percutaneous ultrasound-guided pancreatic biopsy demonstrated no evidence of autoimmune pancreatitis, he was treated with prednisolone to test the efficacy of steroid therapy. However, the pancreatic mass became enlarged after steroid therapy, and he underwent surgery during which the mass was found to be pancreatic cancer. Although the patient was treated with gemcitabine, he died 5 months after surgery. We retrospectively assessed DNA hypermethylation in the patient's pure pancreatic juice obtained on admission. We observed hypermethylation of the cancer-specific gene tissue factor pathway inhibitor 2 (TFPI2). This finding suggests that if the DNA hypermethylation of pure pancreatic juice had been assayed before steroid therapy, it would have supported the diagnosis of pancreatic cancer, and steroid therapy could have been avoided.
    Full-text · Article · Feb 2008 · JOP: Journal of the pancreas
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    ABSTRACT: Pancreatic ductal cancer has higher angiotensin II concentrations compared with normal pancreas or other solid tumors. This study examined angiotensin II type 1 (AT1) receptor expression and the role of angiotensin II in proliferation and survival of human pancreatic cancer cells. All three pancreatic cancer cell lines studied, from well to poorly-differentiated types, HPAF-II, AsPC-1, and Panc-1, showed strong expression of AT1 receptor. In contrast, HT-29 human colon cancer cells showed extremely weak expression. Angiotensin II stimulated the growth of pancreatic cancer cells through MAP kinase activation but had no significant effect on proliferation of HT-29 colon cancer cells. In addition, angiotensin II significantly prevented cisplatin (CDDP)-induced apoptosis through NF-kappaB activation and the subsequent production of anti-apoptotic molecules, including survivin and Bcl-XL, in pancreatic cancer cells. These findings suggest that angiotensin II plays a role in the growth and chemoresistance of AT1-positive pancreatic cancer cells through its action as a potent mitogen and anti-apoptotic molecule.
    No preview · Article · Nov 2004 · International Journal of Oncology