Shinya Onizuka

Vitamin D Binding Protein-Macrophage Activating Factor (DBP-maf) Inhibits Angiogenesis and Tumor Growth in Mice

We have isolated a selectively deglycosylated form of vitamin D binding protein (DBP-maf) generated from systemically available DBP by a human pancreatic cancer cell line. DBP-maf is antiproliferative for endothelial cells and antiangiogenic in the chorioallantoic membrane assay. DBP-maf administered daily was able to potently inhibit the growth of human pancreatic cancer in immune compromised mice (T/C=0.09). At higher doses, DBP-maf caused tumor regression. Histological examination revealed that treated tumors had a higher number of infiltrating macrophages as well as reduced microvessel density, and increased levels of apoptosis relative to untreated tumors. Taken together, these data suggest that DBP-maf is an antiangiogenic molecule that can act directly on endothelium as well as stimulate macrophages to attack both the endothelial and tumor cell compartment of a growing malignancy.

Vitamin D Binding Protein-Macrophage Activating Factor Inhibits HCC in SCID Mice

BACKGROUND A high incidence of recurrence after treatment is the most serious problem in hepatocellular carcinoma (HCC). Therefore, a new strategy for the treatment of the disease is needed. The aim of the present study was to investigate whether vitamin D binding protein-macrophage activating factor (DBP-maf) is able to inhibit the growth of HCC. METHODS The effects of DBP-maf on endothelial cells and macrophage were evaluated by WST-1 assay and phagocytosis assay, respectively. Human HCC cells (HepG2) were implanted into the dorsum of severe combined immunodeficiency (SCID) mice. These mice were divided into control and DBP-maf treatment groups (n = 10/group). The mice in the treatment group received 40 ng/kg/d of DBP-maf for 21 d. RESULTS DBP-maf showed anti-proliferative activity against endothelial cells and also activated phagocytosis by macrophages. DBP-maf inhibited the growth of HCC cells (treatment group: 126 ± 18mm(3), untreated group: 1691.5 ± 546.9mm(3), P = 0.0077). Histologic examinations of the tumors revealed the microvessel density was reduced and more macrophage infiltration was demonstrated in the tumor of mice in the treatment group. CONCLUSION DBP-maf has at least two novel functions, namely, an anti-angiogenic activity and tumor killing activity through the activation of macrophages. DBP-maf may therefore represent a new strategy for the treatment of HCC.

Early Pancreatic Cancer

The results of surgical treatment for ordinary carcinoma of the pancreas, even now considered the only means for cure, have been dismal. In order to define early pancreatic cancer, aiming amelioration of surgical results, early pancreatic cancer has been seeked. It may be readily conceivable that the smaller the tumor size, the earlier the lesion. The relationship between tumor size and surgical results was reviewed from the literature, some of which included articles written in Japanese. Tumor size ≤2 cm in diameter is not always an early cancer. Tumor <1 cm could be an early cancer but does not definitely reveal long-term survival. An increase of pancreatic cancer in Japan may be strongly related with the increased elderly population. Small cystic lesions which develop in elderly persons seem to indicate carcinogenesis of ordinary ductal cancer of the pancreas. Carcinoma in situ may be an early pancreatic cancer. Early pancreatic cancer is defined as an intraductal adenocarcinoma without any invasion or with minimal invasion to the stroma, regardless of size or extent of the lesion.

Pancreatic carcinogenesis: apoptosis and angiogenesis.

Abstract: Apoptosis and angiogenesis are critical biologic processes that are altered during carcinogenesis. Both apoptosis and angiogenesis may play an important role in pancreatic carcinogenesis. Despite numerous advances in the diagnosis and treatment of pancreatic cancer, its prognosis remains dismal and a new therapeutic approach is much needed. Recent research has revealed that apoptosis and angiogenesis are closely interrelated. Several reports show that a tumor suppresser gene that is expressed in pancreatic carcinoma and related to malignant potential can induce apoptosis and also inhibit angiogenesis. At present, it is generally accepted that tumor growth in cancers, including pancreatic cancer, depends on angiogenesis. We have identified 2 new angiogenesis inhibitors from a conditioned medium of human pancreatic carcinoma cell line (BxPC-3): antiangiogenic antithrombin III (aaAT-III) and vitamin D binding protein–macrophage activating factor (DBP-maf). These molecules were able to regress tumors in severe combined immunodeficiency disease (SCID) mice, demonstrating potent inhibition of endothelial cell proliferation. Moreover, the angiogenesis inhibitors induced tumor dormancy in the animal model. These results suggest that antiangiogenic therapy using angiogenesis inhibitors may become a new strategy for treatment of pancreatic cancer in the near future.

Osteoclast-like giant cell tumour of the gallbladder

We describe a rare carcinoma of the gallbladder containing osteoclast-like giant cells. Well-differentiated adenocarcinoma was found in the mucosa of the fundus, and osteoclast-like giant cells were present mainly in a haemorrhagic mass protruding from the mucosal surface. The metastatic hepatic tumour was composed chiefly, if not exclusively, of osteoclastoma-like cells, but minute carcinomatous elements were also present. There was an apparent transition between the giant cells and tubular structures in both the gallbladder tumour and hepatic tumour. However, ultrastructural study did not reveal any evidence of epithelial differentiation in the giant cells. Immunohistochemical studies suggested that the mononuclear and giant cells were mesenchymal and histiocytic in nature (vimentin and factor XIII a positive). A few exceptional giant cells transforming from the fine tubular structure were positive for epithelial membrane antigen. In conclusion, the osteoclast-like giant cell tumour component was thought to represent mesenchymal metaplasia in pre-existent adenocarcinoma.

Spontaneous Pancreatitis in Spontaneously Hypertensive Rats

The pancreatic lesions in 6- to 36-week-oldspontaneously hypertensive rats (SHR), stroke prone SHR (SHRSP) and Wistar-Kyoto rats (WKY) were examined histopathologically. Inflammatory cell infiltration with hemorrhage and stromal fibrosis became evident in 12-week-old SHR and SHRSP together with acinar atrophy and/or degeneration and ductular proliferation. These changes in SHR and SHRSP were even more prominent at the age of 24 weeks and extremely severe at 36 weeks. In addition, in SHR and SHRSP over 12 weeks of age, small necrosis of acinar cells was found occasionally together with fibrosis and arteriosclerosis. Pancreatic arteriosclerosis was marked in SHR and SHRSP over 24 weeks of age at the level of arterioles <200 p,m in diameter. Adrenergic nerve fibers stained by fluorescence his-tochemistry were present around the pancreatic arteries and ducts and within the parenchyma, and they were denser in SHR and SHRSP than in WKY, indicating hy-perinnervation of the sympathetic nervous system in SHR and SHRSP. It is suggested that the pancreatic ischemia caused by arteriosclerosis due to facilitation of the sympathetic nervous system is an important factor in the pathogenesis of the spontaneous pancreatitis of SHR and SHRSP.

Chemopreventative Effect of Hochu-ekki-to (TJ-41) on Chemically Induced Biliary Carcinogenesis in Hamsters

BACKGROUND Bilioenterostomy is a common surgical technique that is widely used. Recently, clinical studies have revealed that biliary carcinomas can occur after bilioenterostomy. The present study was designed to evaluate whether hochu-ekki-to (TJ-41), a Japanese herbal drug, could prevent chemically induced biliary carcinomas in bilioenterostomized hamsters. MATERIALS AND METHODS Syrian golden hamsters were subjected to choledochojejunostomy and then received subcutaneous injections of N-nitrosobis(2-oxopropyl) amine every 2 weeks at a dose of 10 mg/kg. N-nitrosobis(2-oxopropyl) amine administration was started 4 weeks after surgery. The animals were simultaneously p.o. administered TJ-41 in water every day at a dose of 1000 mg/kg (TJ-41 group). The control hamsters were administered water alone. The hamsters were sacrificed 22 weeks after surgery, and the development of biliary carcinomas, the presence and degree of cholangitis, and the cell kinetic status of the biliary epithelium were evaluated histologically. RESULTS Intrahepatic bile duct carcinomas developed in 15/17 (88%) hamsters in the control group and in only 8/17 (47%) hamsters in the TJ-41 group (P < 0.05). The degree of cholangitis was not different between the two groups. However, the proliferating cell nuclear antigen labeling index of the biliary epithelium in the TJ-41 group (6.46%) was significantly lower than the controls (9.67%) (P < 0.05). These findings indicated that TJ-41 reduced accelerated biliary epithelial cell kinetics after bilioenterostomy, resulting in the prevention of carcinogenesis. CONCLUSION TJ-41 has a preventive effect on chemically induced carcinoma of the biliary tract after bilioenterostomy.

A case of lupus-associated pancreatitis with ruptured pseudoaneurysms

Pancreatitis is a relatively rare complication in systemic lupus erythematosus (SLE). Herein we report a case of SLE with the initial development of acute pancreatitis, subsequently complicated by bleeding pseudoaneurysms. A 55-year-old Japanese woman was admitted to our hospital for the treatment of SLE. During the course of treatment, she complained of upper abdominal pain. An abdominal computed tomography (CT) scan showed that the pancreas was diffusely enlarged, and she was diagnosed with acute pancreatitis. Her pancreatitis was resistant to glucocorticoid therapy and was subsequently associated with pancreatic pseudocysts and recurrent rupture of the pseudoaneurysms. After surgical drainage of the hemorrhagic pseudocysts, the patient’s clinical condition gradually improved with intensive therapies. Our case indicates that lupus pancreatitis can be associated with the potentially fatal complication of recurrent bleeding of pseudoaneurysms.

Endoscopic Sphincterotomy Using the Rendezvous Technique for Choledocholithiasis during Laparoscopic Cholecystectomy: A Case Report.

A 50-year-old male was examined at another hospital for fever, general fatigue and slight abdominal pain. He was treated with antibiotics and observed. However, his symptoms did not lessen, and laboratory tests revealed liver dysfunction, jaundice and an increased inflammatory response. He was then admitted to our hospital and underwent an abdominal computed tomography scan and magnetic resonance cholangiopancreatography (MRCP), which revealed common bile duct (CBD) stones. He was diagnosed with mild acute cholangitis. As the same time, he was admitted to our hospital and an emergency endoscopic retrograde cholangiopancreatography was performed. Vater papilla opening in the third portion of the duodenum and presence of a peripapillary duodenal diverticulum made it difficult to perform cannulation of the CBD. In addition, MRCP revealed that the CBD was extremely narrow (diameter 5 mm). We therefore performed laparoscopic cholecystectomy and endoscopic sphincterotomy using the rendezvous technique for choledocholithiasis simultaneously rather than laparoscopic CBD exploration. After the operation, the patient was discharged with no complications. Although the rendezvous technique has not been very commonly used because several experts in the technique and a large operating room are required, this technique is a very attractive and effective approach for treating choledocholithiasis, for which endoscopic treatment is difficult.

Chemoprevention of Biliary Carcinogenesis

This study was conducted to find out if etodolac, a cyclooxgenase-2 (COX-2)specific inhibitor, could prevent chemically induced biliary carcinogenesis in bilioenterostomized hamsters. Syrian golden hamsters were subjected to choledochojejunostomy and then given subcutaneous injections of N-nitrosobis (2-oxopropyl)amine (BOP) 10 mg/kg body weight every 2 weeks. BOP was started 4 weeks after surgery, and continued for 18 weeks. The animals were simultaneously given etodolac 10 mg/kg body weight in 0.5% methylcellulose solution orally three times per week (etodolac group). The control hamsters were administered methylcellulose solution alone. The hamsters were killed 22 weeks after surgery, and the biliary carcinomas were examined histologically. The presence and degree of cholangitis and the cell kinetic status of the biliary epithelium were also evaluated with special reference to biliary carcinogenesis. Intrahepatic bile duct carcinomas developed in 15 (88%) of 17 hamsters in the control group, but in only 6 (33%) of 18 hamsters in the etodolac group (P < 0.01). The incidence and number of developing biliary carcinomas correlated well with the degree of cholangitis, and severe cholangitis was evident in the controls. The cell kinetic study demonstrated that the proliferating cell nuclear antigen-labeling index of the biliary epithelium was 9.67% in the control group and 5.14% in the etodolac group (P < 0.05). The mean levels of prostaglandin E2 (PGE2) products in the liver tissue were 14.14 ± 3.31 pg/total protein (TP) mg in the control group, and 7.46 ± 2.34 pg/TP mg in the etodolac group (P < 0.05). These findings indicated that etodolac inhibited the occurrence of severe cholangitis and the acceleration of biliary epithelial cell kinetics after bilioenterostomy, thereby preventing BOP-induced biliary carcinogenesis in hamsters. In conclusion, the COX-2-specific inhibitor, etodolac, could be used to prevent not only reflux cholangitis, but also biliary carcinoma after bilioenterostomy.