Yasushi Shiratori
Okayama University
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Annals of Internal Medicine | 2003
Yasushi Shiratori; Shuichiro Shiina; Takuma Teratani; Masatoshi Imamura; Shuntaro Obi; Shinpei Sato; Yukihiro Koike; Haruhiko Yoshida; Masao Omata
Context Hepatocellular carcinoma often follows hepatitis C virus infection. Currently available treatments for hepatocellular carcinoma are unsatisfactory. Percutaneous ethanol injection therapy into tumor nodules shows some promise, but recurrence rates are high. Contribution In a carefully selected group of 74 patients with multicentric hepatocellular carcinoma, mild hepatitis C, and mild cirrhosis, patients randomly assigned to receive interferon in addition to ethanol injections showed improved survival at 5 and 7 years, particularly among patients with a sustained virologic response. Cautions Combined treatment of multicentric hepatocellular carcinoma offers the possibility of enhanced survival for carefully selected patients; this study is small, however, and enrolled only patients with low virus levels and mild cirrhosis. The Editors Chronic hepatitis C virus (HCV) infection is a common, frequently asymptomatic disease. Despite the clinically quiescent course of HCV infection, it may slowly progress to cirrhosis and, eventually, to hepatocellular carcinoma (1, 2). Cirrhosis is a major risk factor for the development of hepatocellular carcinoma (3, 4), and 70% to 80% of patients with hepatocellular carcinoma in Japan have HCV infection (5). Current strategies for treating hepatocellular carcinoma include surgical resection, transarterial embolization, percutaneous ethanol injection therapy, radiofrequency wave ablation, and chemotherapy (6-9). Recent studies have shown that percutaneous ethanol injection therapy is effective for hepatocellular carcinoma when the tumors are small (<3 to 5 cm in diameter) and limited in number; survival rates are similar to those obtained with surgery (10-12). Five-year survival rates, however, are poor (30% to 60% for both hepatectomy and percutaneous ethanol injection therapy). Poor prognosis may be the result of the high incidence of tumor recurrence; the cumulative recurrence rate at 5 years is 60% to 100% (10-13). Several studies have evaluated the factors that contribute to the recurrence of hepatocellular carcinoma (12, 13). Occasionally, early recurrence develops adjacent to the treated lesion (local recurrence, 6% to 33% depending on tumor size) (14), but most tumors (80% to 90%) recur at different sites (15). Because hepatocellular carcinoma recurrence and decompensation of underlying liver disease are major problems after medical or surgical treatment, liver transplantation is another option for treating small, unresectable hepatocellular carcinomas in patients with cirrhosis. Studies report 5-year survival rates as high as 75% with liver transplantation (16-18). Interferon therapy has beneficial effects in chronic HCV infection (19, 20). In long-term follow-up studies, sustained virologic responders have remained in remission with normal liver function and improved histologic features of inflammation; in some of these responders, fibrosis even regresses (21, 22). Recently, the frequency of hepatocellular carcinoma in patients receiving interferon therapy has substantially decreased, especially in patients with sustained virologic and biochemical responses (23-25). This decreased frequency has occurred even in patients with cirrhosis (25, 26). Our study evaluated whether complete ablation of neoplastic nodules and administration of antiviral therapy could increase survival rates. Methods Study Design Our prospective study was designed by an eight-member committee in December 1992. The Ethics Committee of the University of Tokyo approved the study. We obtained informed consent from each patient in accordance with the Helsinki declaration. Patients with compensated cirrhosis, three or fewer nodules of hepatocellular carcinoma, and low HCV RNA loads were recruited after complete ablation of the lesions. Eligibility Criteria Inclusion Criteria Hepatitis C virus infection was diagnosed on the basis of identification of anti-HCV antibody using the passive hemagglutination test (Dinabbot, Tokyo, Japan) or enzyme-linked immunosorbent assay (ELISA; Ortho Diagnostic Systems, Tokyo, Japan). Hepatitis C virus RNA was identified by reverse transcriptase polymerase chain reaction (RT-PCR). The serum HCV RNA level was measured by competitive reverse transcriptase (CRT)-PCR according to the method of Kato and colleagues (27); HCV genotype was determined by the method of Okamoto and colleagues (28). Hepatocellular carcinoma was suspected on the basis of several imaging methods, including abdominal ultrasonography, dynamic computed tomography (CT), magnetic resonance imaging (MRI), and arteriography. We confirmed the diagnosis by histologic examination of tumor biopsy specimens obtained from all patients. Evaluation was based on the criteria of the International Working Party (29). In addition, we obtained and evaluated biopsy specimens from non-neoplastic lesions according to the methods of Desmet and colleagues (30). Hepatocellular carcinoma was treated with percutaneous ethanol injection therapy (7, 8, 10). Real-time linear-array scanners were used with 3.5-MHz transducers for the sonographic guidance of needles [21-gauge with a 15-cm or 20-cm needle; Hanako, Tokyo, Japan] into the tumors. Two to 10 mL of 99.5% ethanol was injected into each lesion. Ethanol injection was repeated several times at different sessions. Complete destruction of the nodules was confirmed on dynamic CT 1 month after ethanol injection according to the following criteria: 1) The destructive area was larger than the area of the tumor nodule shown on pretreatment dynamic CT and 2) dynamic CT showed no early-phase contrast enhancement of nodules (7, 8, 10). Inclusion criteria were as follows: 1) hepatocellular carcinoma with three or fewer lesions [verified by histologic examination] and dynamic CTconfirmed complete ablation of hepatocellular carcinoma lesions by percutaneous ethanol injection therapy, 2) detection of HCV RNA by RT-PCR and an HCV RNA load of 2 106 copies/mL or less by CRT-PCR (the cutoff value was based on unpublished data indicating that interferon treatment was effective in patients with HCV RNA loads of 105 copies/50 L of serum by CRT-PCR [27]], 3) platelet count of 50 109 cells/L, 4) leukocyte count of 3 109 cells/L or greater, 5) compensated cirrhosis in ChildPugh stage A, 6) age younger than 70 years, 7) no previous treatment with interferon, and 8) submission of informed consent. Exclusion Criteria Exclusion criteria were as follows: 1) liver diseases due to other causes, such as hepatitis B or primary biliary cirrhosis; 2) HCV RNA load of 2 106 copies/mL or greater by CRT-PCR; 3) severe comorbid diseases, such as heart disease, lung disease, or diabetes mellitus; 4) decompensated cirrhosis in ChildPugh stage B or C; and 5) failure to obtain informed consent. Randomization Patients who enrolled in the study were randomly assigned in a 2:1 ratio to the interferon group or the control group by the controller. We assigned patients to the treatment group or control group by using a randomization list. Interferon Therapy and Follow-up of Patients Interferon Therapy We started interferon therapy with natural interferon- (Sumitomo Pharmaceuticals, Tokyo, Japan) 2 to 3 months after tumor ablation was confirmed. Patients received 6 million U of interferon by intramuscular injection three times weekly for 48 weeks as outpatients. If patients could not tolerate this dose, the interferon dose was reduced to 3 million U. If HCV RNA in serum was still detected by RT-PCR (detection limit, 102 copies/mL) after 24 weeks of interferon therapy and serum alanine aminotransferase (ALT) levels were higher than pretreatment ALT levels, therapy was discontinued. Criteria for Interferon Response We defined the efficacy of interferon therapy virologically and biochemically. Patients who were negative for HCV RNA (as determined by RT-PCR; detection limit, 102 copies/mL) more than 6 months after the completion of interferon therapy were classified as showing a sustained virologic response. Patients with persistently normal ALT levels after the completion of interferon therapy were classified as showing a sustained biochemical response; patients with abnormal ALT levels were classified as showing a nonsustained biochemical response. Follow-up Patients attended a monthly medical consultation at the University of Tokyo Hospital outpatient clinic. Blood biochemical measures, including -fetoprotein (AFP) tumor markers, were measured every 1 to 2 months; ultrasonography was performed every 2 to 3 months; and dynamic CT was performed every 6 months. Recurrence of hepatocellular carcinoma was detected by the finding of abnormal nodules with low or high echogenic appearance on abdominal ultrasonography or by the finding of abnormal density on dynamic CT. The diagnosis was confirmed histologically through ultrasonography-guided fine-needle biopsy of the tumor. Recurrent nodules were divided into two categories [14, 15]: 1) local recurrence, in which the nodule appeared adjacent to the previously treated nodules, suggesting that residual tumor cells had not been completely ablated by percutaneous ethanol injection therapy, or 2) new foci developing at a distant site. New foci of hepatocellular carcinoma, as well as local recurrent nodules at tumor, node, metastasis (TNM) stage I, II, and III, were mainly treated by a second course of percutaneous ethanol injection therapy; local recurrent nodules at TNM stage IV were treated with transarterial chemoembolization or chemotherapy. New development of hepatocellular carcinoma and survival of the patients (tumor recurrence rate and survival rate) were analyzed in relation to the time interval after initial treatment. Statistical Analysis When estimating the sample size, we assumed that 5-year survival in the control group would be 40% according to the data of our previous unpublished study. We predicted that 5-year survival would be increased by 35% as a result of treatment
Clinical Gastroenterology and Hepatology | 2003
Kenji Hirano; Yasushi Shiratori; Yutaka Komatsu; Natsuyo Yamamoto; Naoki Sasahira; Nobuo Toda; Hiroyuki Isayama; Minoru Tada; Takeshi Tsujino; Ryo Nakata; Tateo Kawase; Tetsuo Katamoto; Takao Kawabe; Masao Omata
BACKGROUND & AIMS The aim of this study was to define the bile duct changes associated with autoimmune pancreatitis. METHODS Eight patients with autoimmune pancreatitis were followed for a mean of 4 years. The clinical features of these patients, including extrapancreatic bile duct changes, were examined by using biochemical parameters and several imaging modalities. Pathologic features of the pancreas and liver were examined by using the biopsy specimens of 7 patients. RESULTS Diffuse or focal narrowing of the main pancreatic duct was observed in all patients. Histologic examination of the pancreas showed lymphoplasmacyte infiltration with severe fibrosis and acinar cell depletion. In 6 patients extrapancreatic bile duct changes such as stricture of the bile duct at hilus or intrahepatic area were observed. In 2 patients abnormalities in the bile duct and pancreas were detected simultaneously at diagnosis, and changes in the bile duct were observed later in 4 patients. Lymphoplasmacyte infiltration and fibrosis were observed in the portal area of all 7 liver biopsy samples. Five of the patients with bile duct changes received steroid therapy, and the pathological changes improved. CONCLUSIONS Extrapancreatic bile duct changes are frequently associated with autoimmune pancreatitis. Similar pathogenic mechanism might produce the biliary tract and pancreatic abnormalities in autoimmune pancreatitis resulting in a similar histopathology in the liver and pancreas and response to steroid therapy.
Laboratory Investigation | 2003
Ryo Terada; Kazuhide Yamamoto; Tomomi Hakoda; Noriaki Shimada; Nobuaki Okano; Nobuyuki Baba; Yoshifumi Ninomiya; M. Eric Gershwin; Yasushi Shiratori
Although stromal cell–derived factor-1 (SDF-1) plays an important role in hematopoiesis in the fetal liver, the role after birth remains to be clarified. We investigated the role of SDF-1 and its receptor, CXCR4, in 75 patients; this included controls and patients with viral hepatitis, liver cirrhosis, primary biliary cirrhosis, primary sclerosing cholangitis, and autoimmune hepatitis. Interestingly, SDF-1 appeared up-regulated in biliary epithelial cells (BEC) of inflammatory liver disease. Furthermore, in inflammatory liver diseases, SDF-1 was expressed by BEC of interlobular and septal bile ducts and by proliferated bile ductules. The message expression of SDF-1 in BEC was confirmed at a single-cell level by RT-PCR and laser capture microdissection. The plasma levels of SDF-1 were significantly higher in patients with liver diseases than in normal controls. Flow cytometric analysis of the surface expression of CXCR4 showed that most liver-infiltrating lymphocytes express CXCR4 and the intensity was up-regulated more significantly in liver-infiltrating lymphocytes than in peripheral blood lymphocytes. These results suggest that increased SDF-1 production by BEC may play an important role in the recruitment of CXCR4-positive inflammatory cells into the diseased livers. These data are significant because modulation of the SDF-1/CXCR4 interaction has therapeutic implications for inflammatory liver diseases.
Cardiovascular Pathology | 2003
Issei Komatsubara; Takashi Murakami; Shozo Kusachi; Keigo Nakamura; Satoshi Hirohata; Junichi Hayashi; Shunji Takemoto; Chisato Suezawa; Yoshifumi Ninomiya; Yasushi Shiratori
Osteonectin and osteopontin, two secreted matricellular proteins, have a variety of functions that are exerted through interaction with matrix components. These proteins appear in response to tissue injury. To test our hypothesis that osteopontin and osteonectin are expressed with spatially and temporally different patterns in myocardial infarct tissue, we investigated osteonectin and osteopontin expression in experimentally induced myocardial infarction in rats, in comparison with Type I collagen expression. Northern blotting demonstrated that osteonectin mRNA did not markedly increase on Day 2 after the infarction, but it increased on Days 7 and 14 by 1.7+/-0.12- and 1.8+/-0.01-fold compared to that in preligation hearts. In contrast, osteopontin mRNA was increased on Day 1 (41.9+/-11.3-fold increase) and on Day 2 (58.3+/-7.6-fold increase), and then it declined on Days 7 and 14 (24.8+/-9.0- and 13.5+/-4.7-fold increase, respectively). In situ hybridization revealed that osteonectin mRNA signals were observed in fibroblasts, myofibroblasts and macrophages around infarct necrotic tissue on Days 7 and 14. Osteopontin mRNA signals were observed in macrophages in the infarct marginal zone on Day 2. Immunopositive staining for both osteonectin and osteopontin showed the same pattern as that obtained by in situ hybridization. The time course of osteonectin mRNA was almost parallel with that of Type I collagen mRNA, while that of osteopontin was not. These results demonstrated spatially and temporally different expression patterns of osteonectin and osteopontin in myocardial infarction and suggest that osteonectin appears to be involved in the pathological course in the late phase after infarction concomitantly with Type I collagen, while osteopontin may play a role in the early phase.
Journal of Gastroenterology | 2003
Yasuo Tanaka; Masaki Takayanagi; Yasushi Shiratori; Yasuo Imai; Shuntaro Obi; Ryosuke Tateishi; Miho Kanda; Tomonori Fujishima; Masatoshi Akamatsu; Yukihiro Koike; Keisuke Hamamura; Takuma Teratani; Takashi Ishikawa; Shuichiro Shiina; Masamichi Kojiro; Masao Omata
Congenital absence of the portal vein is an extremely rare anomaly, in which enteric blood bypasses the liver and drains into the inferior vena cava. A 16-year-old girl was referred to our hospital presenting with liver tumor. Although she had suffered from galactosemia soon after birth, the galactosemia had improved spontaneously 1 year later. Between the ages of 8 and 12 years, chronic hepatitis with a mild elevation of aspartate transaminase (AST) and alanine transaminase (ALT) was observed, but liver tumor had not been detected on computed tomography (CT) in regular medical examinations. However, at age 16, liver tumors, 10 cm in diameter, were found. Abdominal angiography indicated complete absence of the portal vein, suggesting that enteric blood was bypassing the liver and draining into the inferior vena cava. In biopsy specimens obtained under ultrasonographic guidance, liver tumors were confirmed histologically as hyperplastic nodules. In addition to this case report, the clinical features of 25 reported cases of congenital absence of the portal vein are reviewed.
Scandinavian Journal of Gastroenterology | 2003
Hirofumi Tsugeno; Motowo Mizuno; S. Fujiki; Hiroyuki Okada; Makoto Okamoto; Yasuhiro Hosaki; S. Ashida; Fumihiro Mitsunobu; Yoshiro Tanizaki; Yasushi Shiratori
Background: Treatment of gastroesophageal reflux (GER) with proton-pump inhibitors (PPI) improves symptoms of asthma in some patients. However, the effects of a PPI on ventilatory function are still controversial. In this study, we measured ventilatory function in asthma patients treated with a PPI in order to identify those in whom a therapeutic effect on asthma can be expected from the acid suppression. Methods: From a cohort of 114 consecutive patients with bronchial asthma, 53 patients agreed to participate in the study and were treated with rabeprazole 20 mg daily for 8 weeks during an asymptomatic, stable period with no exacerbations of their asthma. Of the 53 patients, 22 were diagnosed as GER on the basis of the QUEST questionnaire and endoscopic examination. The patients were monitored for improvement in ventilatory function. Results: Four patients dropped out because of adverse drug reactions. All the patients with GER noted an improvement in reflux symptoms with PPI treatment. An improvement of more than 20% in peak expiratory flow (PEF) was observed in 8 of 21 GER patients but in none of the non-GER patients. Factors predictive of improvement in PEF with rabeprazole therapy were the QUEST score (odds ratio: 1.47, 95% CI: 1.06-2.04, P = 0.022) and steroid-dependency of asthma (odds ratio: 0.01, 95% CI: 0.001-0.31, P = 0.008). Conclusions: Treatment with rabeprazole is expected to ameliorate asthma in non-steroid-dependent patients who have symptomatic GER defined by the QUEST score.
Journal of Clinical Immunology | 2003
Noriaki Shimada; Kazuhide Yamamoto; Marcelo J. Kuroda; Ryo Terada; Tomomi Hakoda; Hiroyuki Shimomura; Hidenori Hata; Eiichi Nakayama; Yasushi Shiratori
We analyzed the prevalence and longitudinal fluctuation of hepatitis B virus (HBV)-specific CD8 T cells in chronic HBV infection using an HLA-A2–HBc18-27 tetramer. Thirty-five HLA-A2-positive patients with chronic HBV infection were divided into 17 HBe antigen (HBeAg)-positive and 18 anti-HBe antibody (anti-HBe)-positive patients. Five HLA-A2-positive normal subjects, five HLA-A2-negative patients with chronic HBV infection, and two HLA-A2-positive patients with acute HBV infection were included as controls. HBc18-27-specific CD8 T cells (c18-27-CD8Ts) were detected at a significantly higher prevalence in patients with anti-HBe (6/18) than in those with HBeAg (1/17), and their frequency reached 0.28% of the total CD8 T cells. The prevalence was significantly higher in patients with HBV DNA below 4.0 log genome equivalents (LGE)/ml (5/12) than in those with HBV DNA above 4.0 LGE/ml (2/23). The frequency of c18-27-CD8Ts was consistently higher in liver-infiltrating lymphocytes, ranging from 0.18 to 1.28%, than in autologous peripheral blood lymphocytes. Longitudinal analysis of patients with acute flare-up demonstrated that the elevation of alanine aminotransferase (ALT) was intimately associated with the expansion of c18-27-CD8Ts. Phenotypic analysis revealed that most c18-27-CD8Ts during acute flare-up expressed HLA-DR and CCR5, while those during low-ALT periods showed low expression. Furthermore, most liver-infiltrating c18-27-CD8Ts were positive for HLA-DR and CCR5, suggesting selective recruitment of activated c18-27-CD8Ts into the liver. In conclusion, HBV-specific CD8 T cells play an important role in the suppression of virus replication, and acute flare-up is associated with the expansion and activation of HBV-specific memory cells.
Journal of Gastroenterology and Hepatology | 2003
Toru Onishi; Kazuhiro Nouso; Toshihiro Higashi; Nobuyuki Toshikuni; Harushige Nakatsukasa; Yoshiyuki Kobayashi; Masayuki Uemura; Eiichiro Yumoto; Keishi Fujiwara; Shuichiro Sato; Shinichiro Nakamura; Junko Yokoyama; Tadashi Hanafusa; Yasushi Shiratori
Background and Aim: Telomerase is the enzyme that synthesizes telomeric DNA, and the activation of telomerase is closely related to cellular immortality. Telomerase activity has been reported in many human cancer tissues and is regulated by the expression of human telomerase reverse transcriptase (hTERT). The aim of the present study was to identify hTERT‐expressing cells in human liver tissues and evaluate the feasibility of the hTERT promoter for gene therapy of hepatocellular carcinoma (HCC).
The American Journal of Gastroenterology | 2003
Masakatsu Mizuno; Motowo Mizuno; Naofumi Iwagaki; Junichirou Nasu; Hiroaki Okazaki; Kazuhide Yamamoto; Hiroyuki Okada; Takao Tsuji; Teizo Fujita; Yasushi Shiratori
OBJECTIVES:We previously reported that the measurements of stool decay-accelerating factor (DAF), a membrane-bound, complement regulatory protein, may be valuable for the detection of colorectal cancer. Recently we have refined the immunoassay for stool DAF. In the present study, using the refined assay, we measured stool DAF concentrations in multiple samples from patients with colorectal cancer and in healthy controls to determine whether testing of multiple samples would increase the sensitivity of the stool DAF test.METHODS:DAF was measured in three spontaneously passed stool samples from each of 100 patients with colorectal cancer and 100 control subjects without apparent colorectal disease.RESULTS:The stool DAF concentrations in the patients with colorectal cancer (median 11.1 ng/g stool; interquartile range 2.9–32.7 ng/g) were significantly higher than concentrations in the subjects without colorectal diseases (median 1.6 ng/g stool; interquartile range 0.4–3.4 ng/g) (p < 0.0001). Testing of two samples from each patient significantly increased the sensitivity (72%) of the stool DAF test without significantly decreasing its specificity (92%). The stool DAF test was positive in more than one half of patients with colorectal cancer at a relatively early TNM stage or with negative fecal occult blood test.CONCLUSIONS:These findings suggest that stool DAF is a marker of colorectal cancer independent of fecal occult blood and testing of two samples increases the sensitivity of the stool DAF test. Measurement of stool DAF now seems worthy of further consideration as a noninvasive method for the detection of colorectal cancer.
Journal of Laboratory and Clinical Medicine | 2003
Mikihiro Kawada; Motowo Mizuno; Junichirou Nasu; Tokurou Uesu; Hiroaki Okazaki; Hiroyuki Okada; Hiroyuki Shimomura; Kazuhide Yamamoto; Takao Tsuji; Teizo Fujita; Yasushi Shiratori
The expression of decay-accelerating factor (DAF), a cell-membrane-complement regulator, is enhanced in colorectal cancer, and DAF is detected in the stools of patients with colorectal cancer. In this study, to elucidate mechanisms whereby DAF is released into the colonic lumen, we analyzed and compared the properties of DAF in stools and colorectal-cancer tissues. Stool specimens taken before surgery and tissue samples from surgically resected colorectal cancers were obtained from 21 patients. We analyzed DAF in stool and tissue specimens using immunoblotting, ultracentrifugation, and phase separation with Triton X-114. We analyzed the expression profile of DAF mRNA in cancer tissues using reverse transcription-polymerase chain reaction to determine whether DAF transcripts for a secretory form of DAF were present. With the use of immunoblotting, stool DAF was detected as a broad band with a molecular weight of around 70,000 kDa that migrated slightly more slowly than cancer-tissue DAF. About 90% of stool DAF was present as a soluble form that remained in the 100,000 g supernatant after ultracentrifugation. On phase separation with Triton X-114, the soluble stool DAF was partitioned mainly into the aqueous phase, indicating its hydrophilic nature and lack of the fatty-acid glycosylphosphatidylinositol anchor component. In colorectal cancer tissues, reverse transcription-polymerase chain reaction experiments revealed a nonspliced DAF messenger RNA that encodes a secretory form of DAF in just 2 of the 21 specimens examined. These data suggest that DAF is released from colorectal cancer cells by way of cleavage of membrane-bound DAF at the site of the glycosylphosphatidylinositol anchor.