Hybrid artificial liver using hepatocyte organoid culture

We developed 2 types of hybrid artificial liver modules using hepatocyte organoid culture. One was a polyurethane foam (PUF)/hepatocyte spheroid packed-bed module. Hepatocytes spontaneously formed spheroids in the PUF pores, and they maintained liver-specific functions well for at least 2 weeks in vitro. As a preclinical experiment, a hybrid artificial liver with 200 g porcine hepatocytes was applied to a pig (25 kg) with liver failure and showed that the hybrid artificial liver was effective in support of liver functions and stabilization of general conditions. We established a new technique of hepatocyte organoid formation using centrifugal force. A hepatocyte organoid formed by centrifugation in hollow fibers maintained functions for more than 4 months in vitro. We developed a new sinusoid-like structure module having hollow fibers arranged by spacers in a micro-regular arrangement. Inoculated hepatocytes in the extra-fiber space of the module formed the organoid by centrifugation, and they maintained the functions for at least 1 month in vitro. The results indicated that this module seems to be promising as a hybrid artificial liver.     

Carcinoma of the colon metastatic to the lower gingiva

A case of carcinoma of the colon that metastasized to the lower gingiva is described. The patient who had carcinoma of the colon developed a proliferating lesion at the site of a recent tooth extraction. A few days later, the primary site of the malignancy appeared. The clinical features in such cases were reviewed in studies by others, most of which were of oral and dental surgery. Thus, because of our case, gastroenterologists should consider the possibility of gingival metastasis from malignant disease such as colorectal cancer.     

Nurturing young surgeons in a competitive society

Creating and maintaining harmony between natural science and social science is very important for the establishment of a truly rich society in the 21st century. Young surgeons must acquire deep knowledge and excellent techniques, in addition to contributing to social development and human happiness. This paper outlines my personal views of what young surgeons need to do to succeed at all levels in the current competitive society.     

Characteristics of multicentric hepatocellular carcinomas: comparison with intrahepatic metastasis

Characteristics of multicentric hepatocellular carcinomas (HCCs) remain obscure. We therefore aimed to clarify them and compare them with HCC with intrahepatic metastases. A series of 118 patients who had definite hepatitis C viral status and multinodular HCC were divided into two groups: a multicentric occurrence (MO) group (n= 38), with multicentric HCCs; and an intrahepatic metastasis (IM) group (n= 80), with HCC having intrahepatic metastases. Clinicopathologic variables, including the patient's survival and disease-free survival rates, were compared between the MO and IM groups. Univariate analysis revealed the presence of esophageal varices, the presence of hepatitis C virus infection, a platelet count of less than 10 × 10⁴/μl, hepaplastin test, γ-globulin, the histologically active hepatitis, tumor size, des-γ-carboxy prothrombin > 0.1 AU/ml, positive portal vein invasion, and histologic grade as discriminating factors. The MO score to differentiate multicentric HCCs from intrahepatic metastatic HCCs was determined using the following four independent factors selected by a stepwise regression analysis: the presence of hepatitis C virus infection, a platelet count of less than 10 × 10⁴/μl, tumor size, and histologic grade. The sensitivity and specificity of the MO scores using those factors were 84% and 70%, respectively, when the cutoff value was 0.4. The disease-free survival rate in the MO group was similar to that in the IM group, whereas the survival rate in the MO group was significantly better than that in the IM group. The multivariate analysis revealed the multicentric occurrence of HCC as one of the independent prognostic factors. Clinicopathologic factors differentiating multicentric HCCs from intrahepatic metastatic HCCs were the presence of hepatitis C virus infection, a platelet count of less than 10 × 10⁴/μl, small tumor size, and low histologic grade.     

Growth pattern and expressions of cell cycle regulator proteins p53 and p21WAF1/CIP1 in early gastric carcinoma.

BACKGROUND: The growth pattern of early gastric carcinoma, as based on a volumetric analysis, reflects the biologic characteristics of a tumor. The penetrating growth (Pen) type tumor has an unfavorable prognosis, compared with the case of a superficially spreading (Super) type. The wild-type of the p53 protein plays an important role in cell growth regulation and apoptosis. The p21 protein, which is encoded by the WAF1/CIP1 gene, is a downstream target effector of wild-type p53 protein, and these proteins act as tumor suppressors in a negative cell-cycle regulation. METHODS: In 133 Japanese patients with early gastric carcinoma with submucosal invasion, expressions of p53 and p21 proteins were studied immunohistochemically, and the relation between growth pattern and expressions was analyzed. RESULTS: Early gastric carcinomas were grouped into the superficially spreading (Super) type 40 (30.1%) cases, expansively penetrating growth (Pen-A) type 28 (21.1%), infiltratively penetrating growth (Pen-B) type 20 (15.0%), small mucosal type 35 (26.3%), and mixed type 10 (7.5%). The Pen-A type tumors were characterized by the highest incidence of p53 expression and loss of p21 expression, and the rate of p53-positive and/or p21-negative cases was 71.4%. There were significant differences in the incidence of the p53 expression (50.0% vs.25.0%), the loss of p21 expression (53.6% vs. 27.5%), and the 5-year survival rate (83.2 %vs. 97.2%) between the Pen-A type and the Super type. CONCLUSIONS: Thus, deregulation of the cell cycle by p53 and p21 in this study was shown to play an important role in progression of Pen-A type early gastric carcinoma.     

Pilot study of combination chemotherapy of S-1, a novel oral DPD inhibitor, and interferon-alpha for advanced hepatocellular carcinoma with extrahepatic metastasis

BACKGROUND: To the authors' knowledge, there is no effective therapy for extrahepatic metastasis of hepatocellular carcinoma (HCC). In a pilot study, the results of combination therapy of S-1, a novel oral dehydropyrimidine dehydrogenase (DPD) inhibitor, and interferon-alpha (IFN-alpha) are reported for HCC patients with extrahepatic metastasis. METHODS: Twelve patients with extrahepatic metastasis of HCC were enrolled in the pilot study. S-1 was administered orally at a dose based on body surface area, twice daily after a meal, for 4 weeks. IFN-alpha was injected subcutaneously on Days 1, 3, and 5 of each week. One course consisted of consecutive administration for 28 days followed by 14 days rest. RESULTS: An objective response was observed in 3 (25%) of 12 patients. The overall 1-year survival rate was 61.7%. Grade 3 leukocytopenia was observed in 1 patient (8.3%). No severe toxicity or treatment-related deaths were observed. CONCLUSIONS: The combination therapy of S-1 and IFN-alpha appears to be highly efficacious, with low toxicity in patients with extrahepatic metastases of HCC. The combination chemotherapy of oral S-1 and subcutaneous IFN-alpha is a potentially promising treatment strategy for advanced HCC with extrahepatic metastasis.     

Defective mitogen-activated protein kinase (ERK2) signaling in gastric mucosa of portal hypertensive rats: potential therapeutic implications.

Portal hypertensive (PHT) gastropathy is a frequent, serious complication of liver cirrhosis. PHT gastric mucosa has numerous abnormalities such as reduced mucosal potential differences, reduced surface oxygenation, and increased susceptibility to injury caused by alcohol, aspirin, and other noxious factors. Because such mucosal injury is initially mediated by oxygen free radicals, and because mitogen-activated protein (MAP) kinase (ERK2) protects against cellular stress and induces cell proliferation, we postulated that oxidative stress-induced ERK2 activation is defective in PHT gastric mucosa. Here we show that in PHT gastric mucosa, ERK2 activation by oxidative stress is impaired. This impairment is mediated by overexpression of MAP kinase phosphatase-1 (MKP-1), which results from the underlying and continual oxidative state associated with portal hypertension, and is ameliorated by inhibiting MKP-1. Furthermore, we found that supplementing vitamin E, a free radical scavenger, reduces the oxidative state in PHT gastric mucosa, normalizes MKP-1 expression, and thereby reverses impairment of oxidative stress-induced ERK2 activation. Finally, we show that orally administered vitamin E completely reverses the increased susceptibility of PHT gastric mucosa to alcohol injury. Our findings point to a new molecular and mechanistic basis for PHT gastropathy and provide a new therapeutic modality for protection of PHT gastric mucosa.     

Features and outcome of neonatal leukemia in Japan: experience of the Japan infant leukemia study group

BACKGROUND: Neonatal leukemia characterized by early stem cell origin and extramedullary infiltration in the first 4 weeks of life is rare. We analyzed the features and outcome of neonatal leukemia in Japan to establish an appropriate treatment strategy for this rare disorder. PROCEDURE: Patients with infant leukemia registered and treated in the Japan Infant Leukemia Study between 1996 and 2001 were analyzed. RESULTS: Among 162 infant leukemia patients, 11 exhibited neonatal leukemia; frequencies for all infant leukemias were 6.9% (8/116) for acute lymphoblastic leukemia (ALL) and 7.3% (3/41) for acute myeloid leukemia (AML). Positive MLL gene rearrangement was observed in all eight patients with ALL; a single patient with AML displayed germline configuration. Acute monoblastic leukemia was apparent in all three patients with AML (M5a in the FAB classification). Most of the patients demonstrated hepatoplenomegaly and hyperleukocytosis at diagnosis. Cutaneous and central nervous system involvement were detected in half of the patients. Four patients (one with AML, and three with ALL) have survived following stem cell transplantation (SCT); however, growth impairment related to SCT was observed in these patients. CONCLUSIONS: These results suggest an improvement attributable to treatment of neonatal leukemia. International-based collaborative studies are necessary to investigate the biology of this condition and to establish appropriate therapeutic strategies.