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Biomedical subjects

Kazutaka Kurokohchi

Publications and source records attributed to Kazutaka Kurokohchi.

At least 19 recordsLinked to original sources
PubMed2007

Identification of c-Yes expression in the nuclei of hepatocellular carcinoma cells: involvement in the early stages of hepatocarcinogenesis.

It is thought that the subcellular distribution of Src-family tyrosine kinases, including c-Yes binding to the cellular membrane, is membranous and/or cytoplasmic. c-Yes protein tyrosine kinase is known to be related to malignant transformation. However, the expression patterns of c-Yes in hepatocellular carcinoma (HCC) remains unknown. In the present study, we report that c-Yes is expressed not only in the membrane and cytoplasm, but also in the nuclei of cancer cells in some human HCC tissues and in a human HCC cell line. We examined the expression and localization of c-Yes in human HCC cell lines (HLE, HLF, PLC/PRF/5 and Hep 3B) by Western blotting and immunohistochemical analyses; we also examined the expression of c-Yes by immunohistochemistry and Western blotting in the tissues of various liver diseases, including 39 samples from HCC patients. We used an antibody array to detect proteins that bind to nuclear c-Yes in PLC/PRF/5 cell line. c-Yes was found to be expressed in the membranes and cytoplasm of HLE, HLF and Hep 3B HCC cells; it was also detected in the nuclei in addition to the membranes and cytoplasm of PLC/PRF/5 HCC cells. HCC with nuclear c-Yes was detected in 5 of 39 cases (13.0%), and nuclear c-Yes expression was not detected in normal, chronic hepatitis or cirrhotic livers. All HCCs with nuclear c-Yes expression were well-differentiated, small tumors at the early stages. In the PLC/PRF/5 cell line, the nuclear localization of c-Yes with cyclin-dependent kinase 1 was confirmed by a protein antibody array. In conclusion, nuclear c-Yes expression was found in cancer cells at the early stages of hepatocarcinogenesis, suggesting that nucleus-located c-Yes may be a useful marker to detect early-stage HCC.

Adult↗
PubMed2007

Sequential assessment of the intrahepatic expression of epidermal growth factor and transforming growth factor-beta1 in hepatofibrogenesis of a rat cirrhosis model.

Responses of the liver to chronic injury include inflammation, regeneration and fibrosis, which finally lead to cirrhosis. The cause of liver cirrhosis appears to be impaired proliferative capability of hepatocytes caused by continuous hepatic damage, and subsequent accumulation of extracellular matrix produced by hepatic stellate cells (HSCs). Epidermal growth factor (EGF) and transforming growth factor-beta1 (TGF-beta1) play a crucial role in hepatocyte proliferation and hepatofibrogenesis, respectively. However, sequential analyses of the intrahepatic expression of EGF and TGF-beta1 in the course of cirrhosis development have not been examined fully. In the present study, liver cirrhosis was produced in rats by intraperitoneal administration of dimethylnitrosamine (DMN), and intrahepatic mRNA expression levels of proliferating cell nuclear antigen (PCNA), EGF and TGF-beta1 were quantitatively estimated by a real-time reverse transcription-polymerase chain reaction method. Histological and semiquantitative densitometric examination of liver sections revealed that the accumulation of extracellular matrix components was increased according to the period of DMN treatment. Histological examination of liver sections of rats treated with DMN for 4 and 6 weeks revealed pre-cirrhosis and cirrhosis, respectively. Intrahepatic mRNA expression levels of PCNA and EGF correlated well. Expression levels of both molecules were increased significantly during the course of cirrhosis development, but decreased significantly at the time of complete cirrhosis manifestation. In contrast, intrahepatic TGF-beta1 expression was increased significantly according to the period of DMN treatment, and reached a peak at the time of cirrhosis manifestation. These results suggest that proliferative capability of hepatocytes was impaired by continuous liver damage due, in part, to the decrease of a hepatocyte mitogen EGF, and that increased intrahepatic TGF-beta1 activated HSCs to retrieve space lost by hepatocyte destruction, resulting in complete cirrhosis manifestation.

Animals↗
PubMed2006

Analysis of CD28 and bcl-2 expression on peripheral blood and liver-infiltrating mononuclear cells in patients with autoimmune hepatitis.

Because the underlying mechanism of hepatocellular damages in autoimmune hepatitis (AIH) still remains unclear, analysis of CD28 and bcl-2 molecules, which are critical for T cell activation and survival, was performed in patients with AIH. The number of CD28(+)CD4(+) peripheral blood mononuclear cells (PBMC) in corticosteroid (CS)-treated patients was comparable to normal control individuals but decreased in untreated AIH patients. In contrast, the number of CD28(+)CD8(+) PBMC was decreased in both CS-treated and untreated AIH patients. Analysis of liver-infiltrating mononuclear cells (LIMC) showed that the number of CD28(+)CD4(+) and CD28(-)CD8(+) LIMC were positively correlated with the histology activity index score. Bcl-2(+)CD4(+) LIMC were observed in the portal area of the liver and the numbers fluctuated with disease activity during the time course after CS administration. By contrast, CD8(+) LIMC were shown not to express bcl-2. Taken collectively, these results suggest that bcl-2(+)CD28(+)CD4(+) and bcl-2(-)CD28(-)CD8(+) cells may play critical and distinct roles in hepatocellular damage in AIH.

Adrenal Cortex Hormones↗
PubMed2006

Usefulness of liver infiltrating CD86-positive mononuclear cells for diagnosis of autoimmune hepatitis.

AIM: Although the pathogenic mechanism underlying autoimmune hepatitis (AIH) remains unclear, the immune system is thought to be critical for the progression of the disease. Cellular immune responses may be linked to the hepatocellular damage in AIH. Recently, much attention has been focused on the critical functions of costimulatory molecules expressed on mononuclear cells in the generation of effective T cell-mediated immune responses. Analysis of costimulatory molecule expressed on mononuclear cells from the patients with AIH may give us insight into the pathogenic mechanism of hepatocellular damage in AIH. METHODS: Peripheral blood mononuclear cells (PBMC) were taken from the patients with AIH (34 cases) and healthy controls (25 cases). Liver infiltrating mononuclear cells (LIMCs) were taken from the patients with AIH (18 cases), the patient with chronic hepatitis C (CH-C) (13 cases) and the patients with fatty liver (2 cases). Using flow cytometry, the cells were analyzed for the expression of costimulatory molecules, such as CD80, CD86, and CD152 (CTLA-4). The results were compared with clinical data such as the level of gammaglobulin, histological grade, presence or absence of corticosteroids administration and the response to corticosteroids. RESULTS: The levels of CD80+, CD86+ and CD152+ PBMC were significantly reduced in the patients with AIH as compared with healthy controls. By contrast, those cells were significantly higher in LIMC than in PBMC of the patients with AIH. Especially, the level of CD86+ LIMC showed a marked increase irrespective of the degree of disease activity in the patients with AIH, although CD86+ cells were rarely present in PBMC. The levels of CD86+ cells were present in significantly higher frequency in patients with AIH than in the patients with CH-C. Furthermore, the patients with AIH with high levels of CD86+ LIMC showed good responses to corticosteroids, whereas 2 cases of AIH with low levels of CD86+ LIMC did not respond well. CONCLUSION: These results suggest that LIMC over-expressing costimulatory molecules such as CD80 and CD86 appears to play a role in the pathogenesis of AIH. Especially, CD86 molecule expressed on the LIMC may be useful for the diagnosis of AIH and for the prediction of the therapeutic effects of corticosteroids on AIH.

Adrenal Cortex Hormones↗
PubMed2006

Multidisciplinary treatment of patients with hepatocellular carcinoma.

Hepatocellular carcinoma is one of the most common malignancies in the world. When it is diagnosed, patients can choose from among several potentially curative treatments, such as surgical resection, transplantation, ablation therapy and transcatheter arterial chemoembolization. This review will give an overview of the present management of hepatocellular carcinoma. Liver transplantation is considered the best curative option, achieving a high rate of complete response, especially in patients with small hepatocellular carcinoma and good residual liver function. However, a shortage of donor livers restricts the availability of transplantation. In addition, only a minority of patients with hepatocellular carcinoma can be treated surgically, owing to impaired hepatic reserve, multiple intrahepatic lesions, extrahepatic lesions and the inability to obtain an optimal tumor-free margin. Therefore, for most patients, other types of interventions (transcatheter arterial chemoembolization, percutaneous ethanol injection and radiofrequency ablation) have been developed. Among them, two local ablative modalities, percutaneous ethanol injection and percutaneous radiofrequency ablation, have been accepted as the only potentially curative nonsurgical treatments for hepatocellular carcinoma. Radiofrequency ablation may become a standard nonsurgical treatment option for patients with early hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed2006

Time-lag performance of radiofrequency ablation after percutaneous ethanol injection for the treatment of hepatocellular carcinoma.

We have previously reported that the combination therapy of percutaneous ethanol injection and radiofrequency ablation (PEI-RFA) was more effective than RFA alone to induce wider coagulated necrosis for the treatment of hepatocellular carcinoma (HCC). In the present study, the effect of time-lag performance of RFA after PEI was evaluated under the same ablation condition as PEI-RFA by analyzing the volume of coagulated necrosis, the energy requirement for ablation and the amount of ethanol injected into HCC. The comparative study between time-lag PEI-RFA and no time-lag PEI-RFA showed that the total energy requirement and the energy requirement per unit volume for whole and marginal coagulated necrosis were significantly smaller in the time-lag group than in the no time-lag PEI-RFA group. In time-lag PEI-RFA, the volume of coagulated necrosis induced positively correlated with the amount of ethanol injected into HCC as previously observed in PEI-RFA treatment. These results suggest that time-lag PEI-RFA can induce comparable coagulated necrosis with a smaller energy requirement than no time-lag PEI-RFA, and that time-lag PEI-RFA is likely to be less invasive than no time-lag PEI-RFA for inducing comparable coagulated necrosis. Thus, time-lag performance of RFA after PEI may make RFA treatment more effective and less invasive for the treatment of patients with HCC.

Aged↗
PubMed2006

Thoracoscopic ethanol injection and radiofrequency ablation for the treatment of hepatocellular carcinoma located immediately under the diaphragm.

We previously reported that the combination therapy of percutaneous ethanol injection and radiofrequency ablation (PEI-RFA) was more effective than RFA alone in inducing wider coagulated necrosis for the treatment of hepatocellular carcinoma (HCC). In the present study, we thoracoscopically applied the combination therapy to the treatment of HCC located immediately under the diaphragm. RFA electrode and ethanol injection needle were inserted into the tumor through the right side of the diaphragm in 6 patients with HCC close to the diaphragm. In all cases, the tumor was completely ablated with enough safety margin around the tumor. No local tumor recurrence has been observed in a relatively short-time follow-up period. The volume of coagulated necrosis and the energy requirement for coagulation in thoracoscopic ethanol injection and RFA (T-EI-RFA) were comparable to those of PEI-RFA. Although HCC located immediately under the diaphragm is difficult to treat with a percutaneous approach due to the poor visualization by ultrasonography, T-EI-RFA is considered to be an effective treatment modality.

Carcinoma, Hepatocellular↗
PubMed2006

Successful treatment of large-size advanced hepatocellular carcinoma by transarterial chemoembolization followed by the combination therapy of percutaneous ethanol-lipiodol injection and radiofrequency ablation.

We report a case of large-size hepatocellular carcinoma (HCC) successfully treated with transarterial chemoembolization (TACE) followed by the combination therapy of percutaneous ethanol-lipiodol injection and radiofrequency ablation (PELI-RFA) and percutaneous ethanol-lipiodol injection (PELI) therapy. In the present case, the patient had a large-size advanced HCC, 7 cm in diameter, located in the S8 region of the liver. In addition, the hepatic reserve of the patient was severely poor. In order not to impair the poor hepatic reserve, we chose PELI-RFA and PELI, originally developed in our department and reported as milder treatment modalities than others. After TACE , PELI-RFA and PELI were performed several times, the HCC was totally destroyed and early enhancement shown by helical dynamic computed tomography disappeared completely after treatment. The hepatic reserve of the patient was not impaired by the series of treatments. Serum levels of tumor markers, alpha-fetoprotein and Des-gamma-carboxy prothrombin, were rapidly decreased to almost normal levels. PELI-RFA and PELI may be effective for the treatment of large-size HCC of patients with poor hepatic reserve.

Aged↗
PubMed2005

Successful treatment of advanced hepatocellular carcinoma by combined administration of 5-fluorouracil and pegylated interferon-alpha.

We report a case of hepatocellular carcinoma (HCC) treated successfully by transarterial chemoembolization (TACE) followed by combination therapy of 5-fluorouracil (5-FU) and pegylated interferon-alpha (PEG-IFN-alpha). In the present case, the patient had massive and advanced HCC with a diameter of over 8 cm located in segment 7 (S7) of the liver. Furthermore, the tumor invaded into the major branch of the portal vein (Vp3). After TACE, combined administration of 5-FU and PEG-IFN-alpha was performed for 5 mo. HCC was totally eradicated and the serum levels of tumor markers were markedly decreased by the treatment. Although it has been reported that the combined use of conventional IFN-alpha and 5-FU showed striking effects on HCC in some cases, this case may suggest the more promising effect of PEG-IFN-alpha with a long-lasting effect, in the combined use with 5-FU for the treatment of massive advanced HCC.

Aged↗
PubMed2005

Comparison between combination therapy of percutaneous ethanol injection and radiofrequency ablation and radiofrequency ablation alone for patients with hepatocellular carcinoma.

AIM: In the present study, the characteristics of PEI-RFA treatment were further elucidated by analyzing the relationship between the volume of coagulated necrosis and the energy requirement for ablation or the amount of ethanol injected into HCC. METHODS: The volume of coagulated necrosis, total energy requirement and energy requirement for coagulation of per unit volume were examined in the groups of PEI-RFA and RFA alone using the Cool-tip RF system. RESULTS: The results showed that the volume of coagulated necrosis induced was significantly larger in PEI-RFA group than in routine RFA group, when the total energy administered was comparable in both groups. In PEI-RFA, enlargement of coagulated necrosis was admitted in 3 dimensions and the amount of energy requirement per unit volume of coagulated necrosis was negatively correlated with the amount of ethanol injected into HCC. CONCLUSION: These results suggest that, compared to RFA alone, PEI-RFA enables to induce comparable coagulated necrosis with smaller energy requirement, and that PEI-RFA is likely to be less invasive than RFA alone irrespective of inducing enhanced coagulated necrosis. Thus, simple prior injection of ethanol may make RFA treatment more effective and less invasive for the treatment of patients with HCC.

Administration, Cutaneous↗
PubMed2005

Successful laparoscopic radiofrequency ablation of hepatocellular carcinoma adhered to the mesentery after transcatheter arterial embolization.

A 54-year-old male with hepatocellular carcinoma (HCC) underwent transcatheter arterial embolization (TAE) at a nearby hospital. He was then referred to our hospital for the purpose of additional treatment of HCC. Because TAE was not a complete therapy and HCC was growing and protruding from the left lobe of the liver, laparoscopic radio-frequency ablation (RFA) was chosen for the treatment of HCC. After inserting a laparoscope into the abdominal cavity, it was observed that HCC unexpectedly adhered to the mesentery as a result of TAE performed previously. After cutting off the adhered mesentery and removing it from the tumor, the combination therapy of percutaneous ethanol injection and RFA (PEI-RFA), developed at our department, was performed on the tumor. The tumor was successfully abrogated by PEI-RFA and the sufficient safety margin was confirmed by computed tomography after the treatment.

Arteries↗
PubMed2005

Adenovirus-mediated gene transfer into rat livers: comparative study of retrograde intrabiliary and antegrade intraportal administration.

To examine the feasibility of liver-directed in vivo gene therapy, we administered recombinant adenoviruses carrying a reporter lacZ gene retrogradely into the common bile duct of rats, as well as antegradely into the portal vein. Transduction efficiency of the lacZ gene in the liver was estimated not only histochemically by X-gal staining, but also quantitatively by a chemiluminescent reporter gene assay. Retrograde infusion of adenoviruses into the common bile duct was shown to successfully induce transgene expression in the liver. Transduction efficiency induced by intrabiliary adenoviral administration was not significantly different from that induced by intraportal adenoviral administration. Although transgene expression induced not only by intraportal, but also by intrabiliary adenoviral administration was observed predominantly at periportal areas, a considerable number of cells expressing the transgene were detectable even in lobular and centrilobular areas. Mild infiltration of inflammatory cells into the liver and mild hyperplastic changes of hepatocytes were observed after intrabiliary and intraportal adenoviral administration. However, hepatic damage estimated pathologically was not substantial. Furthermore, although intrabiliary and intraportal adenoviral administration resulted in very mild elevation of liver-related serum biochemical parameters, apparent complications were not observed in any rats. Our results demonstrated in the present study suggest that retrograde administration of adenoviruses into the common bile duct can induce efficient transgene expression in the liver without causing severe adverse effects, supporting the feasibility of adenovirus-mediated gene transfer into the liver in clinical settings by means of endoscopic retrograde cholangiography.

Adenoviridae↗
PubMed2005

Comparison study of the expressions of myristoylated alanine-rich C kinase substrate in hepatocellular carcinoma, liver cirrhosis, chronic hepatitis, and normal liver.

The myristoylated alanine-rich C kinase substrate (MARCKS) is a prominent substrate for protein kinase C (PKC) in a variety of cells. The aim of this study was not only to evaluate the expression and localization of MARCKS in various pathological liver tissues, including HCC, but also to analyze the difference in MARCKS expression between hepatitis virus-induced HCC and cirrhosis. The level of MARCKS and its phosphorylated proteins, as well as its localization, were determined using Western blot and/or immunohistochemistry in HCC and other pathological liver tissues. We also analyzed the change of MARCKS localization on the influence of MARCKS phosphorylation in the HLF cancer cell line by phosphorylation study. In addition, the relationship between MARCKS expression and proliferative activity was studied in HCC. In the immunohistochemical study, a very small amount of MARCKS protein was found along the contour of the hepatocellular membrane in normal liver and in cases of chronic hepatitis. MARCKS was up-regulated in liver cirrhosis tissue and was localized in the cytoplasm of hepatocytes. The expression of MARCKS was down-regulated in HCC tissues, as compared with non-tumorous liver cirrhosis tissues from the same patients. Furthermore, MARCKS was serine-phosphorylated in liver cirrhosis and HCC, and phosphorylated MARCKS was detected in a cytosolic fraction of these tissues. In a phosphorylation study using the HLF HCC cell line, MARCKS was displaced from the plasma membrane to the cytosol following the activation of protein kinase C (PKC) by phorbol 12-myristrate 13-acetate (PMA). Furthermore, the activity of cyclin D1 and cyclin E kinases was found to be higher in HCCs with low MARCKS expression than in HCCs with high MARCKS expression. These results suggest that up-regulation of MARCKS might be essential in the generation of cirrhotic nodules through chronic hepatitis from normal liver, and that the phosphorylation and/or down-regulation of MARCKS might play an important role in the development and progression of HCC from liver cirrhosis.

Adult↗
PubMed2005

Antitumor effects of vitamins K1, K2 and K3 on hepatocellular carcinoma in vitro and in vivo.

A number of studies have shown that various K vitamins, specifically vitamins K2 and K3, possess antitumor activity on various types of rodent- and human-derived neoplastic cell lines. In the present study, we examined the antitumor effects of vitamins K1, K2 and K3 on PLC/PRF/5 human hepatocellular carcinoma (HCC) cells in vitro and in vivo. Furthermore, we examined the mechanisms of antitumor actions of these vitamins in vitro and in vivo. Although vitamin K1 did not inhibit proliferation of PLC/PRF/5 cells at a 90-microM concentration (the highest tested), vitamins K2 and K3 suppressed proliferation of the cells at concentrations of 90 and 9 microM, respectively. By flow cytometric analysis, it was shown that not only vitamin K1, but also vitamin K2 did not induce apoptosis or cell cycle arrest on PLC/PRF/5 cells. In contrast, vitamin K3 induced G1 arrest, but not apoptosis on PLC/PRF/5 cells. Subsequent in vivo study using subcutaneous HCC-bearing athymic nude mice demonstrated that both vitamins K2 and K3 markedly suppressed the growth of HCC tumors to similar extent. Protein expression of cyclin D1 and cyclin-dependent kinase 4 (Cdk4), but not p16INK4a Cdk inhibitor in the tumor was significantly reduced by vitamin K2 or K3 treatment, indicating that vitamins K2 and K3 may induce G1 arrest of cell cycle on PLC/PRF/5 cells in vivo. Taken collectively, vitamins K2 and K3 were able to induce potent antitumor effects on HCC in vitro and in vivo, at least in part, by inducing G1 arrest of the cell cycle. The results indicate that vitamins K2 and K3 may be useful agents for the treatment of patients with HCC.

Animals↗
PubMed2005

Enhanced expression of p46 Shc in the nucleus and p52 Shc in the cytoplasm of human gastric cancer.

Shc protein is known to be related to cell proliferation and carcinogenesis. However, the involvement of Shc in gastric cancer remains unknown. In the present study, we examined the expression and localization of Shc in human gastric cancer and the adjacent normal mucosa by Western blotting and immunohistochemical analyses. Furthermore, the expression of Shc in a gastric cancer cell line, MKN 28, was also studied. p66 Shc was not detected at all in gastric cancer or the adjacent normal mucosa. In contrast, immunohistochemical and Western blot analyses revealed that p52 Shc was detected in the cytoplasmic fractions obtained from gastric normal mucosa and cancer, while p46 Shc expression was observed in the nuclear fractions from gastric normal mucosa and cancer. Furthermore, not only p52 Shc expression in the cytoplasm but also p46 Shc expression in the nucleus was much higher in gastric cancer than in the adjacent normal mucosa. Subsequent in vitro experiments with MKN 28 gastric cancer cells also revealed that p52 Shc was expressed solely in the cytoplasm and p46 Shc was solely in the nucleus. These results suggest that the enhancement of p46 Shc and p52 Shc expression may be related to the occurrence of gastric cancer. Furthermore, unlike p52 Shc, p46 Shc was shown to be expressed solely in the nucleus, suggesting that p46 Shc expressed in the nucleus may play an important role in gastric carcinogenesis.

Adaptor Proteins, Signal Transducing↗