Kenji Ohmoto

Comparison of therapeutic effects between radiofrequency ablation and percutaneous microwave coagulation therapy for small hepatocellular carcinomas

Background:  Although thermal ablation therapies have gained fairly wide acceptance as an effective treatment for small hepatocellular carcinoma (HCC), there have been only a few clinical studies comparing the response to radiofrequency ablation (RFA) and percutaneous microwave coagulation therapy (PMCT). We evaluated the therapeutic efficacy and safety of these two procedures for the treatment of small HCC measuring ≤ 2 cm in diameter.

Complications of radiofrequency ablation for hepatocellular carcinoma in a multicenter study: An analysis of 16 346 treated nodules in 13 283 patients

Aim:  We surveyed multiple centers to identify types and frequency of complications and mortality rate associated with radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC).

Cryopreservation of primarily isolated porcine hepatocytes with UW solution.

Development of liver-targeted cell therapies, such as hepatocyte transplantation and bioartificial livers, requires a large amount of functional hepatocytes as needed. To achieve this development, establishing an excellent cryopreservation method of hepatocytes is an extremely important issue. Therefore, we performed a comparative review of cryoprotective effects of various cryopreservation solutions using primarily isolated porcine hepatocytes. Porcine hepatocytes were isolated with a four-step dispase and collagenase perfusion method. The obtained hepatocytes with the initial viabilities of 76%, 84%, and 96% were assigned to the following four groups for cryopreservation at −80°C: Dulbeccos modified Eagles medium (DMEM) + 10% fetal bovine serum (FBS) + 12% dimethyl sulfoxide (DMSO) (group A), University of Wisconsin (UW) solution + 12% DMSO (group B), Cell Banker 1 (group C), and Cell Banker 2 (group D). The hepatocytes in each group were thawed at 3 days, 10 days, and 5 months of cryopreservation and subjected to comparative analyses, including viability, plating efficiency, LDH release, ammonia removal test, and lentiviral gene transfer. These parameters were the most favorable in the hepatocytes cryopreserved with UW solution. Approximately 5% of thawed cryopreserved porcine hepatocytes expressed LacZ activity after lentiviral transduction. Intrasplenic transplantation of UW solution-cryopreserved hepatocytes improved the survival of rats treated with D-galactosamine. UW solution maintained the functions of cryopreserved porcine hepatocytes.

Long-term effect of bezafibrate on parameters of hepatic fibrosis in primary biliary cirrhosis

1. Francke U, Brown MS, Goldstein JL. Assignment of the human gene for low density lipoprotein receptor to chromosome 19: synteny of a receptor, a ligand and a genetic disease. Proc Natl Acad Sci USA 1984;81:2826–30. 2. Starzl TE, Bilheimer DW, Bahnson HT, Shaw BW Jr, Hardesty RL, Griffith BP, et al. Heart-liver transplantation in a patient with familial hypercholesterolemia. Lancet 1984;1:1382–3. 3. Shirahata Y, Ohkohchi N, Kawagishi N, Syouji M, Tsukamoto S, Sekiguchi S, et al. Living-donor liver transplantation for homozygous familial hypercholesterolemia from a donor with heterozygous hypercholesterolemia. Transpl Int 2003;16:276–9.

Spontaneous regression of focal nodular hyperplasia of the liver

Focal nodular hyperplasia (FNH) of the liver is a rare benign lesion that probably reflects a local hyperplastic response of hepatocytes to a vascular abnormality. Currently, the natural history of the disease remains largely unknown. We present a patient with FNH of the liver who was followed up for 4 years. A 22-year-old woman with a 3-year history of oral contraceptive use was referred to our hospital in September 1996 for further examination of a liver tumor. A diagnosis of FNH was made using various imaging methods, such as ultrasonography, enhanced computed tomography (CT) scanning, MR imaging, and hepatic angiography, as well as fine-needle biopsy. A decrease in the size of the lesion was observed by enhanced CT scanning during the 4-year observation period. In this patient, oral contraceptive use and its discontinuation may have influenced the natural history of FNH. The present case suggests that an accurate diagnosis is of the utmost importance, and a patient with FNH should be managed conservatively rather than by resection, because FNH has the potential for spontaneous regression with the discontinuation of oral contraceptives.

Maintenance of cold-preserved porcine hepatocyte function with UW solution and ascorbic acid-2 glucoside.

Normal human hepatocytes are an ideal source of liver-targeted cell therapies, such as hepatocyte transplantation and bioartificial livers, but availability of human donor livers for liver cell isolation is severely limited. To effectively utilize scarce donor organs for cell therapies, it is of extreme importance to establish an efficient isolation technique and an effective cold preservation solution for transportation of isolated cells. A lateral segment of the liver was surgically resected from pigs weighing 10 kg and a four-step collagenase and dispase digestion was conducted. Isolated hepatocytes were subjected to 8-h cold storage on ice. The following preservation solutions were tested: 1) University of Wisconsin (UW) solution, 2) UW with 100 μg/ml of ascorbic acid-2 glucoside (AA2G), 3) 100% fetal bovine serum (FBS), and 4) Dulbeccos modified Eagles medium (DMEM) supplemented with 100% FBS. The mean viability of porcine hepatocytes was 95.5 ± 2.5% when isolated in three independent experiments. Viability, plating efficiency, membrane stability, and ammonia metabolic capacity of cold-preserved hepatocytes were significantly better maintained by the use of UW solution. When AA2G (100 μg/ml) was combined with UW solution, such parameters were further improved. It was explained by inhibition of caspase-3 activation and retention of ATP at high levels of hepatocytes preserved with UW solution containing AA2G. The present work demonstrates that a combination of UW solution with AA2G (100 μg/ml) would be a useful cold preservation means for the development of cell therapies.

Improved Prognosis of Cirrhosis Patients with Esophageal Varices and Thrombocytopenia Treated by Endoscopic Variceal Ligation Plus Partial Splenic Embolization

The aim of this study was to assess the efficacy of the combination of endoscopic variceal ligation (EVL) and partial splenic embolization (PSE) compared with EVL alone in cirrhosis patients with thrombocytopenia. In a prospective study, 84 cirrhosis patients with esophageal varices and thrombocytopenia (platelet count < 50,000/mm3) underwent EVL plus PSE (N = 42) or EVL alone (N = 42). Primary end points assessed during the follow-up period included the recurrence of varices, progression to variceal bleeding, and death. Comparison between combined treatment and variceal ligation alone by multivariate analysis showed a hazard ratio of 0.44 for the recurrence of varices (P = 0.02), 0.19 for progression to variceal bleeding (P = 0.01), and 0.31 for death (P = 0.04). These results suggest that the combination of EVL plus PSE can prevent the recurrence of varices, progression to variceal bleeding, and death in cirrhosis patients with esophageal varices and thrombocytopenia.

Transduction of immortalized human hepatocytes with p21 to enhance differentiated phenotypes.

We previously constructed an immortal human hepatocyte line NKNT-3 with a simian virus 40 T antigen (SV40T) to develop cell-based biological therapies. p21 is a molecule that regulates the transition from the G1 phase to the S phase of the cell cycle. Investigators have demonstrated that overexpression of p21 induces differentiation in various cell lines. In the current study we examined the effect of p21 on differentiated phenotypes of SV40T-immortalized NKNT-3 cells. A replication-deficient adenovirus vector expressing a human wild-type p21 cDNA under the control of the CMV promoter (Ad5CMVp21) and a human wild-type p21 protein fused to the protein transduction domain from the human immunodeficiency virus (HIV) TAT protein (TAT/p21) were utilized to achieve efficient delivery of p21 into NKNT-3 cells. Morphological alterations, cell cycle progression, and expression of albumin and p-450 associated enzymes (CYPs) 3A4 and 2C9 were evaluated in NKNT-3 cells treated with Ad5CMVp21 and TAT/p21. Efficient adenovirus-based p21 transfer and TAT-mediated p21 protein delivery were confirmed in NKNT-3 cells in an immuno-fluorescence study and Western blotting analysis. Transduction of NKNT-3 cells with p21 predominantly arrested the cell cycle at the G1 checkpoint, resulting in differentiated hepatic phenotypes in morphology and improvement in protein expression of albumin, CYP 3A4, and CYP C29. We here show that exogenous expression of p21 augments cellular differentiation in immortalized human NKNT-3 cells.

Long-term evaluation of partial splenic embolization for liver cirrhosis and hepatocellular carcinoma accompanied by hypersplenism

Abstract The long-term effectiveness of partial splenic embolization (PSE) was assessed in patients with liver cirrhosis (LC) and hepatocellular carcinoma (HCC) accompanied by hypersplenism. A total of 54 patients with LC accompanied by hypersplenism were classified into the following three groups: 18 LC patients without HCC who received PSE (group 1); 18 LC patients with unresectable HCC who were simultaneously treated with PSE and transcatheter arterial embolization (TAE) (group 2); and 18 LC patients with unresectable HCC who received TAE alone (group 3). In 36 patients (groups 1 and 2), PSE was indicated when a patient presented with splenomegaly and thrombocytopenia or leukopenia. The group 2 patients continued to show significant increases in the platelet and white blood cell counts and improvement in the hepatic reserve even 2 years after PSE, similar to the group 1 patients. The blood flow through the portal trunk was not significantly affected by PSE, but the splenic venous flow volume decreased significantly, probably reflecting a relative increase in nutritious blood supply from the alimentary tract. These hemodynamic changes may be involved in the post-PSE improvement of the hepatic reserve. As for the group 2 patients, a combination of PSE and TAE resulted in a significantly better prognosis than in the group 3 patients who received TAE alone. However, because of the significantly poor prognosis, PSE is unlikely to be indicated for Child C patients.

Angioedema after interferon therapy for chronic hepatitis C

1. Nolan CM, Sandblom RF, Thummed KE. Hepatotoxicity associated with acetaminophen usage in patients receiving multiple drug therapy for tuberculosis. Chest 1994;105:408–11. 2. Nicod L, Viollon C, Regnier A. Rifampicin and isoniazid increase acetaminophen and isoniazid toxicity in human HepG2 hepatoma cells. Hum Exp Toxicol 1997;16:28–34. 3. Bolt HM, Kappus H, Bolt M. Effect of rifampicin treatment on the metabolism of oestradiol and 17-ethinylestradiol by human liver microsomes. Eur J Clin Pharmacol 1975;8:301–7. 4. Dimova S, Stoytchev T. Influence of rifampicin on the toxicity and the analgesic effect of acetaminophen. Eur J Drug Metab Pharmacokinet 1994;19:311–7. 5. Steele MA, Burk BF, DesPrez RM. Toxic hepatitis with isoniazid and rifampicin: A meta-analysis. Chest 1991;99:465–71.