Hiroshi Hino

Near Completely Humanized Liver in Mice Shows Human-Type Metabolic Responses to Drugs

Human hepatocytes were transplanted into urokinase-type plasminogen activator-transgenic SCID mice (uPA/SCID mice), which are immunodeficient and undergo liver failure. The transplanted cells were characterized in terms of their in vivo growth potential and functions. The human hepatocytes progressively repopulated the murine host liver. However, the recipients died when the replacement index (RI) of the human hepatocytes exceeded 50%. The hosts (chimeric mice) survived at RI >50% when treated with a drug that has anti-human complement factor activity, and these mice developed livers with RI values as high as 96%. In total, 36 chimeric mice were generated, and the rate of successful engraftment was as high as 92%. The yield of chimeric mice with RI >70% was 32%. The human hepatocytes in the murine host liver expressed mRNAs for a variety of human cytochrome P450 (hCYP) subtypes, in a manner that was similar to the donor liver. The mRNAs for hCYP3A4 and hCYP1A1/2 were induced in the liver in a CYP type-specific manner when the mice were treated with rifampicin and 3-methylcholanthrene, respectively. These results indicate that human hepatocytes that propagate in mice retain their normal pharmacological responses. We conclude that the chimeric mouse developed in the present study is a useful model for assessing the functions and pharmacological responses of human hepatocytes.

Gasless laparoscopic hepatic resection for cirrhotic patients with solid liver tumors.

Gasless laparoscopic hepatic resection with a 5-cm minilaparotomy was performed in 10 cirrhotic patients with small liver tumors. To maintain good visualization and working space during hepatic resections, we developed a simple retraction system. Mean operative time and blood loss were 291 minutes and 249 mL, respectively. No blood transfusion was required during the operations. No serious complications occurred such as gas embolism. Our laparoscopic procedures had various advantages. Blood, smoke, and water vapor could be aspirated by suction without disturbance of the visual field. There was no risk of gas embolism. It was possible to use conventional instruments through the ports or the wound made by a minilaparotomy. Hemostasis therefore could be performed easily. The procedure could be applicable to cirrhotic patients with some complications. This laparoscopic procedure is recommended for patients with small HCCs associated with liver cirrhosis who are not candidates for major hepatectomy.

Granulocyte colony-stimulating factor-producing combined hepatocellular/cholangiocellular carcinoma with sarcomatous change

To the Editor. A 70-year-old man had been admitted to a hospital with complaints of high fever (39.2°C) and upper abdominal pain. Clinical symptoms such as fever, a high serum C-reactive protein (CRP) level (10.7 mg/dl), and computed tomography (CT) findings (Fig. 1a, b) had suggested an erroneous diagnosis of an amebic liver abscess. He was referred to our hospital. Relevant laboratory data were within normal limits, except for granulocytosis (18 000/ml), increased levels of serum CRP (9.5 mg/dl) and carbohydrate antigen 19-9 (119 U/ml), and severe anemia (hemoglobin, 8.5 g/dl). Preoperative serum granulocyte colonystimulating factor (G-CSF; 308 pg/ml; normal range, below 9.8pg/ ml) and interleukin-6 (IL-6; 689 pg/ml; normal range, below 4.0 pg/ml) levels were markedly elevated. The tumor-doubling time was less than 10 days (Fig. 1). The patient underwent palliative hepatectomy with subtotal gastrectomy emergently because of tumor rupture into the peritoneal cavity. Pathological examinations of the resected specimen revealed combined hepatocellular and cholangiocellular carcinoma (combined HCC/CCC) with sarcomatous change, and the production of G-CSF in cancer cells, particularly in the sarcomatous cells (Fig. 2d). The granulocytosis improved transiently just after the operation (7800/ml) and deteriorated again as recurrent tumors advanced (26 400/ml before death). The patient died of sarcomatous cancer metastases to multiple organs on postoperative day 34. Only four cases of combined HCC/CCC with sarcomatous change were reported previously.1 There were no peculiar clinical features, including fever, leukocytosis, on extremely rapid progression of the disease in these four patients; G-CSF production, which was found in the present patient, was not observed in these patients. Only two cases of liver cancer have been reported to be associated with granulocytosis and G-CSF production in the cancer cells.2 These patients had a poor prognosis, with rapid growth of tumors and with high potential for distant metastasis. However, there have been no reports of G-CSF-producing combined HCC/ CCC with sarcomatous changes. Immunohistochemical study in our patient revealed G-CSF staining in the cytoplasm of the majority of the combined HCC/ CCC cells that had transformed to sarcomatoid cells (Fig. 2d). These findings confirm that the combined HCC/CCC with sarcomatoid features was a G-CSF-producing tumor. Several authors have provided strong evidence that G-CSF functions in vitro as a growth-stimulating factor for some types of tumors, in cooperation with IL-6. Kyo et al.3 reported a case of cervical cancer that exhibited an aggressive clinical course, suggesting autocrine stimulation of cell growth by G-CSF and IL-6. High levels of serum IL-6 have been reported in other malignancies, and these were correlated with levels of CRP. IL-6 is thought to be one of the major mediators of fever and production of CRP. In the present patient, the rare manifestations may have resulted from both the sarcomatous transformation of the tumors and the GCSF production by the tumors themselves in association with high levels of serum G-CSF and IL-6. Although the mechanism by which certain liver cancers produce G-CSF has remained unclear, it was reported that there was an intimate relationship between the production of G-CSF in

Indication of Hepatectomy for Cirrhotic Patients with Hepatocellular Carcinoma Classified as Child-Pugh Class B

We clarified the indication of partial hepatectomy in hepatocellular carcinoma (HCC) patients with liver cirrhosis classified as Child-Pugh class B. Univariate analysis revealed that adverse prognostic factors were (1) the presence of ascites, (2) elevated total bilirubin (1.5 mg/dl or higher), (3) reduced choline esterase (160 IU/ or lower), (4) elevated alpha-fetoprotein (AFP) (400 ng/ml or higher), (5) microscopic vascular invasion, and (6) non-curative hepatectomy. Microvascular invasion was excluded in the multivariate analysis because this factor could not be predicted before hepatectomy. Multivariate analysis revealed that independent adverse prognostic factors were (1) elevated total bilirubin (1.5 mg/dl or higher), (2) presence of ascites, (3) elevated AFP (400 ng/ml or higher), and (4) non-curative hepatectomy. The overall 5-year survival rate of patients with none of or only one of the four adverse prognostic factors was 45.8%. The overall 5-year survival rate of patients with two or more adverse prognostic factors was only 7.0%. Partial hepatectomy is the first choice of treatment for patients with none of or only one of the four adverse prognostic factors, whereas orthotopic liver transplantation or other conservative treatment should be considered for patients with two or more adverse prognostic factors.