Expression profiles of genes associated with viral entry in HCV-infected human liver.

Recent studies have demonstrated that several cellular factors are involved in entry of hepatitis C virus (HCV) into host cells. Detailed gene expression profiles of these factors in HCV-infected livers have not been reported for humans. Transcriptional levels of LDL receptor (LDLR), CD81, scavenger receptor class B type I (SR-BI), claudin-1, and occludin genes in liver samples from patients with chronic hepatitis C were investigated. Serum levels of LDL-cholesterol (LDL-C) and HCV core antigen were also evaluated, and expression of claudin-1 and occludin were immunohistochemically analyzed. Compared with normal liver, transcription of LDLR and claudin-1 genes was significantly suppressed (P < 0.0001) and occludin transcription was significantly up-regulated in HCV-infected livers (P < 0.0001). Significant positive correlations were found for LDLR versus occludin, LDLR versus claudin-1, occludin versus claudin-1, and CD81 versus SR-BI in HCV-infected (P = 0.0012, P < 0.0001, P = 0.0004, and P < 0.0001, respectively) and normal livers (P < 0.0001, P = 0.0051, P < 0.0001, and P < 0.0001, respectively). Positive correlation was observed between serum levels of HCV core antigen and LDL-C (P = 0.0147), with their levels negatively correlated to LDLR (P = 0.0270 and P = 0.0021, respectively). Immunohistochemically, hepatocellular expression of claudin-1 and occludin was increased in HCV-infected livers. Different levels of expression were demonstrated at the mRNA and protein levels for occludin and claudin-1 in HCV-infected and normal livers. Correlation of elements associated with viral entry was comparable in HCV-infected and normal livers.

Therapeutic effect of bezafibrate against biliary damage: a study of phospholipid secretion via the PPARalpha-MDR3 pathway.

OBJECTIVE: Bezafibrate (BF) has been used to treat biliary damage, particularly in patients with primary biliary cirrhosis (PBC), and its clinical efficacy has been demonstrated. The mechanism of action is thought to involve activation of the PPARalpha-MDR3-phospholipid (PL) secretion pathway. We tried to confirm this hypothesis in patients with hepatobiliary disease. METHODS: The levels of serum gamma-glutamyl transpeptidase and alkaline phosphatase, and those of bile components were examined before and after BF administration in patients with obstructive jaundice undergoing percutaneous transhepatic biliary drainage (PTBD). Hepatic expression of PPARalpha and MDR3 was quantified by real-time PCR in patients with PBC or non-alcoholic fatty liver disease (NAFLD). RESULTS: In patients with obstructive jaundice, BF decreased the serum levels of biliary enzymes and increased the bile concentration of PL. In patients with PBC or NAFLD, the expression levels of MDR3 were already up-regulated before starting the BF treatment. Although BF treatment did not further up-regulate MDR3 expression in NAFLD patients, PPARalpha expression was significantly increased. CONCLUSIONS: BF enhanced the secretion of PL into bile in cholestatic patients undergoing PTBD. However, in patients with PBC or NAFLD, diseases that represent cholesterol overload, MDR3 was already expressed at a high level to compensate for bile acids overproduction, and its expression was hardly affected by BF. In patients with chronic liver diseases such as PBC, BF may induce clinical effects via mechanisms independent of PL secretion.

Direct association of presenilin-1 with beta-catenin.

Families bearing mutations in the presenilin-1 (PSI) gene develop Alzheimer's disease (AD). However, the mechanism through which PS1 causes AD is unclear. The co-immunoprecipitation with PS1 in transfected COS-7 cells indicates that PSI directly interacts with endogenous beta-catenin, and the interaction requires residues 322450 of PSI and 445-676 of beta-catenin. Both proteins are co-localized in the endoplasmic reticulum. Over-expression of PS1 reduces the level of cytoplasmic beta-catenin, and inhibits beta-catenin-T cell factor-regulated transcription. These results indicate that PSI plays a role as inhibitor of the beta-catenin signal, which may be connected with the AD dysfunction.

Hemorrhagic colitis with unusual colonoscopy features, complicated with chronic graft-versus-host disease after allogeneic bone marrow transplantation.

A 32-year-old man was admitted after bone marrow transplantation because of hematochezia. He had history of chronic graft-versus-host disease (GVHD) of the skin and the liver, and cytomegaloviral pneumonia. Barium enema and colonoscopy showed multiple colon ulcers in the ascending and transverse colon. This feature is very rare in chronic GVHD and resembles the feature in autoimmune disease such as periarteritis nodosa. Thus, this ulceration is thought to be caused by vasculitis due to an autoimmune reaction in chronic GVHD.

Chemical identification of lipid components in the membranous form of rat liver alkaline phosphatase.

Membranous and soluble forms of rat liver alkaline phosphatase were selectively prepared by extracting microsomes with n-butanol at pH 8.5 and 5.5, respectively, and purified in homogeneous forms by the method previously established (Miki et al. (1986) Eur. J. Biochem. 160, 41-48). When subjected to polyacrylamide gel electrophoresis, the two forms migrated to the same position in the presence of sodium dodecyl sulfate, while the membranous form remained at the top of gels in the absence of the detergent. Treatment of the membranous form with phosphatidylinositol-specific phospholipase C resulted in its conversion to a soluble form with the same electrophoretic mobility even in the absence of the detergent as that of the soluble form extracted at pH 5.5. Automated Edman degradation analysis showed that the two forms have the same N-terminal amino acid sequence up to the 30th residue determined. Chemical analyses of hydrolysates of the two forms by gas-liquid chromatography demonstrated that the membranous form contains palmitic acid, stearic acid, and inositol, while the soluble form contains inositol but is devoid of the fatty acids. Taken together, these results suggest that rat liver alkaline phosphatase is covalently attached to phosphatidylinositol acylated with palmitic acid and stearic acid, which functions as the membrane-anchoring domain of the enzyme molecule.

Activation of tau protein kinase I/glycogen synthase kinase-3beta by amyloid beta peptide (25-35) enhances phosphorylation of tau in hippocampal neurons.

According to the amyloid hypothesis for the pathogenesis of Alzheimer's disease (AD), amyloid beta peptide (Abeta) directly affects neurons, leading to neurodegeneration and tau phosphorylation, followed by the production of paired helical filaments (PHF) in neurofibrillary tangles (NFT). To analyze the relationship between the phosphorylation sites of tau and the activation of kinases in response to Abeta, we treated cultured rat hippocampal neurons with a peptide fragment of Abeta, Abeta(25-35). Abeta(25-35) treatment activated tau protein kinase I/glycogen synthase kinase-3beta (TPKI/GSK-3beta) but not glycogen synthase kinase-3alpha (GSK-3alpha) or mitogen activated protein kinase (MAP kinase) in primary culture of hippocampal neurons. Using antibodies that recognize phosphorylated sites of tau, we showed that tau phosphorylation was enhanced in at least five sites (Ser199, Ser202, Ser396, Ser404, and Ser413 numbered according to the human tau isoform containing 441 amino acid residues), to an extent that depended on the level of TPK I/GSK-3beta. Treatment with TPK I/GSK-3beta antisense oligonucleotide inhibited the enhancement of tau phosphorylation induced by Abeta(25-35) exposure. Thus, TPK I/GSK-3beta activation by Abeta(25-35) may lead to extensive tau phosphorylation.

Familial Alzheimer's disease-associated mutations block translocation of full-length presenilin 1 to the nuclear envelope.

A polyclonal antibody, M5, to the hydrophilic loop domain of human presenilin 1 (PS1) was prepared. Western blot and immunoprecipitation analyses showed that M5 specifically recognized the processed C-terminal fragment, but not the full-length PS1. Epitope mapping analysis revealed that the essential sequence for recognition of the C-terminal fragment by M5 is DPEAQRR (302-308). The recognition of the C-terminal fragment by M5 in a processing-dependent manner was further confirmed by competitive enzyme-linked immunosorbent assay using the synthetic peptide L281 (281-311), which contains the putative processing site and the preceding amino acids to the site. Although L281 contains the epitope sequence for M5, the maximum inhibition was only 14%. Immunocytochemistry using M5 combined with hL312, which recognizes both full-length PS1 and the C-terminal fragment, allowed us to distinguish the localization of the processed C-terminal fragment from that of full-length PS1. Confocal microscopy demonstrated that the full-length form of wild-type PS1 is preferentially located in the nuclear envelope, while the processed C-terminal fragment is mainly present in the endoplasmic reticulum (ER). However, PS1 with familial Alzheimer's disease-associated mutations could not translocate to the nuclear envelope, and both the full-length and processed mutants were co-localized in the ER.

Involvement of cyclin dependent kinase5 activator p25 on tau phosphorylation in mouse brain.

P35 or its truncated fragment p25 is required for cyclin dependent kinase (Cdk)5 activation. It has been reported that p25 is accumulated in the brain of Alzheimer's disease (AD) patients and that p25/Cdk5 induces high phosphorylation of tau and apoptosis in cultured neurons (Nature 402 (1999) 615). Our investigation of AD brain did not show specific accumulation of p25. Exposure to Ca ionophore (A23187) at 10(-6) M induced p25 accumulation in rat primary hippocampal neurons, causing neuronal death without showing hyperphosphorylation of tau. Transgenic mice expressing p25 showed the accumulation of p25 but neither hyperphosphorylation of tau nor neuronal death was shown in these mice. The feature of these mice was the progression of cell growth in pituitary gland. These results suggest that overexpression of p25 lead to the activation of cell cycle but not to the direct phosphorylation of tau.

Different effects of Alzheimer-associated mutations of presenilin 1 on its processing.

Presenilin 1 (PS 1) shows missense mutations in most early-onset familial Alzheimer's disease (FAD). Transfection of cDNA for wild type PS 1 into rat pheochromocytoma PC12 cells generated a 47 kDa full-size PS 1 protein, which was processed into a 28 kDa N-terminal fragment and a 19 kDa C-terminal fragment. We prepared selected Alzheimer-associated mutations (Gly384Ala, Leu392Val, and Cys410Tyr) of PS 1, which localized after a possible cleavage site. By transient expression in PC12 cells and rat glioma cell line, C6, we examined their influence on the processing of PS 1. Cys410Tyr inhibited proteolytic processing of PS 1, while Gly384Ala and Leu392Val did not. Thus, the Alzheimer related mutations can be divided into two groups in terms of their effect on the proteolytic cleavage of PS 1.

Abeta amyloidosis induces the initial stage of tau accumulation in APP(Sw) mice.

To clarify how Abeta deposits induce secondary tauopathy, the presence of phosphorylated tau, glycogen synthase kinase 3alpha (GSK3alpha), GSK3beta, cyclin-dependent kinase 5 (CDK5), mitogen-activated protein kinase (MAPK) and fyn were examined in the Tg2576 brain showing substantial brain Abeta amyloidosis and behavioral abnormalities. Phosphorylated tau at Ser199, Thr231/Ser235, Ser396 and Ser413 accumulated in the dystrophic neurites of senile plaques. The major kinase for tau phosphorylation was GSK3beta. Smaller contributions of GSK3alpha, CDK5 and MAPK were suggested. Thus, brain Abeta amyloidosis has a potential role in the induction of tauopathy leading to the mental disturbances of Alzheimer's disease.

Coexistence of choriocarcinoma and adenocarcinoma in the rectum: molecular aspects.

Choriocarcinoma, a malignant tumor of usually placental origin, in divided into two groups; the gestational and non-gestational types, the latter being rare. Non-gestational choriocarcinoma occurs in the lung, mediastinum, kidney, stomach, and small intestine, but rarely appears in the large intestine. We treated a 29-year-old woman with choriocarcinoma of the rectum with adenocarcinoma. Despite the rarity of the condition and the obscurity of the histogenesis, reports of similar cases and the occurrence of the tumors in the digestive tract suggest that the condition constitutes a clinical entity of a digestive tumor.

Combination therapy with cisplatin, 5'-deoxy-5-fluorouridine (5'-DFUR) and mitomycin (MMC) in patients with inoperable, advanced gastric cancer.

The optimal dose of cisplatin (CDDP) for combination chemotherapy for the treatment of inoperable, advanced gastric cancer has yet to be established. We therefore performed a randomized study to compare the therapeutic usefulness of two dose levels of cisplatin. 5'-deoxy-5-fluorouridine (5'-DFUR 1,400 mg/m(2)/d) was given orally on days 1 to 4 and 15 to 18. Mitomycin C (MMC, 5.75 mg/m(2)/d) was injected intravenously on day 5. In addition, 80 mg/m2/d of CDDP (regimen A) or 60 mg/m(2)/d of CDDP (regimen B) was given by 2-h intravenous drip infusion on day 5. This treatment cycle was repeated every four weeks. Fifty-six patients were enrolled. Clinical response was evaluated in 32 patients (regimen A, 16 patients; regimen B? 16 patients) with measurable lesions. The response rate was significantly higher with regimen A (9 PR/16, 56.3%) than with regimen B (3 PR/16, 18.9%) (p=0.028, chi(2) test). Median survival was slightly but not significantly longer with regimen A (7.4 months) than with regimen B (6.3 months). Drug toxicity included myelosuppression and gastrointestinal symptoms, but there were no serious adverse reactions or differences in safety between the treatment regimens. Regimen A was associated with a high response rate and low toxicity. The optimal dose of CDDP in combination with 5'-DFUR and MMC for the treatment of advanced gastric cancer is regarded to be 80 mg/m(2).

Genetic changes in multi-step development of colorectal cancer.

We studied activated mutations of K-ras gene in three forms of colorectal tumors, i.e., 45 specimens of colorectal adenoma (CA), 10 of 'cancer in adenoma' (CIA), and 24 of colorectal cancer (CC), and in 15 of gastric cancer (GC) as controls. Chromosome aberrations were also examined in 7 specimens of CA, 3 of CIA, 8 of CC, and 7 of GC. Mutation of K-ras Codon 12 was observed in 12 (26.7%) of the 45 specimens of CA, 6 (60.0%) of the 10 specimens of CIA, 6 (25.0%) of the 24 specimens of CC, and 1 (6.7%) of the 15 specimens of GC. In CA, its frequency increased with the degree of histological atypism. In CA and CIA, its frequency increased with the increase in short diameter. The most frequent chromosome aberration was the numerical excess of chromosome 7. Numerical deficiencies of chromosomes 17 and 18 or structural abnormalities of 17p+ and 18q+ were noted in 1 specimen each of CA and CIA, and 2 of CC. Thus, aberrations of these two chromosomes were concurrent. 5q--was observed in 1 specimen each of CA and CC. These findings were not contradictory to the multi-step carcinogenesis model of the colorectum based on the hypothesis that carcinogenesis requires activation of an oncogene by mutation accompanied by defects of several genes that might normally inhibit tumorigenesis.

Endoscopic studies on the superficial spreading type of early gastric cancer.

Twenty eight cases out of 230 cases of early gastric cancer showed the superficial spreading type of early gastric cancer. Seventeen stomachs (60.7%) were compatible to the endoscopic finding of spreading cancerous regions, even to macroscopic and microscopic ones. Other 11 cases were not corresponded clinicopathologically to the infiltrated lesions. These 11 cases were studied on the superficial spreading lesions respectively. They were divided into three groups and compared each other micro- and macro-scopically and endoscopically. Group I contained 6 cases, compatible to micro- and macro-scopic findings but not to endoscopic ones. Endoscopic overdiagnosis may be redness and overflow of white fur and underestimate by a few cancer cells superficially in the mucosae, slight difference in height at the margin of II c and cancer without exposure. Group II was similar microscopic and endoscopic findings but not compatible macroscopically. Both cases in group II were overestimated macroscopically at the infiltrated edge because of color change in mucosae but endoscopically diagnosed by changes of color and gastric area. Group III contained 3 cases of microscopic characteristics and not compatible to macroscopic and endoscopic ones. Endoscopic underdiagnosis may be based on a few cancer cells superficially in normal mucosae and on less depressed lesions. These clinicopathological studies might be worthy to clarify the endoscopic and pathologic discrepancies of infiltrating areas by early gastric cancer, and might improve endoscopic techniques of the gastric mucosal observation.

Effects of changing the type of H2-blocker in the treatment of H2-blocker-resistant ulcers: comparison of roxatidine acetate hydrochloride and other H2-blockers.

The efficacy of switching from one type of H2-receptor antagonist (H2-blocker) to another, in the treatment of H2-blocker-resistant ulcers was investigated using H2-blockers with five-membered rings (five-membered-ring agents)--such as cimetidine, ranitidine and famotidine--and an H2-blocker with a six-membered ring, roxatidine. By switching from a five-membered-ring agent to roxatidine in the treatment of five-membered-ring resistant ulcers (study I), gastric ulcers were healed in nine of 19 patients (47%) and duodenal ulcers were healed in eight of nine patients (89%). By switching from roxatidine to one of the five-membered-ring agents in the treatment of roxatidine-resistant ulcers (study II), gastric ulcer was healed in six of 15 patients (40%), and duodenal ulcer was healed in 4 of 10 patients (40%). Particularly in the case of duodenal ulcers, the switch to treatment with roxatidine, which has a different chemical structure from the five-membered-ring agents, may be useful in the treatment of five-membered-ring-resistant ulcers.

[Clinical trial of 5'-deoxy-5-fluorouridine (5'-DFUR) in advanced cancer patients].

5'-DFUR was administered orally to advanced or recurrent cancer patients at a daily dosage of 600-1200 mg divided into 3 or 4 times a day. Out of 13 evaluable cases 2PR, 2MR, 4NC and 5PD were observed, response rate was 15.4%. PR were obtained in one gastric cancer case and one breast cancer case. Side effects were observed in 6 cases out of 14 cases (42.9%) and major adverse reaction was gastro-intestinal toxicities such as anorexia, nausea-vomiting and diarrhea. Two leukocytopenia and one erythrocytopenia were observed. This study indicated that 5'-DFUR would be useful as a new anticancer agent.

[The changes in tumor markers such as serum CEA, CA 19-9, TPA and CA 125 in the chemotherapy of patients with advanced gastric cancer].

Twenty-five patients with advanced gastric cancer were treated with a combination chemotherapy. The levels of serum CEA, CA 19-9, TPA and CA 125 were measured before and during chemotherapy (4 and 8 weeks). One complete and 10 partial responses were obtained, and the response rate was 44%. Pretreatment positive rates of these four tumor markers were all more than 60%, and the positive rate of combination assay was 96%. The mean percent changes of these four tumor markers were similar and correlated well with the response to chemotherapy. There was a significant correlation between tumor reduction and decrease of serum CEA in the responders with measurable lesions. These results suggest that the measurement of changes of serum tumor markers may be useful for monitoring the response to chemotherapy in patients with gastric cancer. It also may be useful to determine early the effectiveness of the treatment.

[A study of combined chemotherapy with MMC, ADM, CDDP, etoposide (VP-16), 5'DFUR (MAC-VD therapy) in advanced cancer and local relapse of the stomach].

Eighteen patients with progressive/locally recurrent cancer of the stomach were given therapy with MMC, ADM, CDDP, Etoposide (VP-16), and 5'DFUR (MAC-VD therapy). Drugs were administered intravenously with MMC 10 mg/m2, ADM 20 mg/m2, and CDDP 50 mg/m2 on day 1; orally with etoposide 100 mg/day for five consecutive days from day 3; and orally with 5'DFUR 600 mg/day for three weeks from day 3 followed by discontinuation for one subsequent week. This drug regimen was one course of the treatment and repeated as far as possible. There were 16 evaluable cases; the sex distribution was ten males and six females. Patients ranged in age from 43 to 78 years. P.S. 1 was two cases; 2 ten cases; and 3 four cases. The overall response rate, CR + PR, was 1 + 7/16 (50%), while this rate for primary disease was 2 + 5/16 (43.8%). Of the two CR cases, one primary lesion became operable and CR was demonstrated histologically. The overall response rates, CR + PR, for metastatic lesions were 1 + 3/9 (44.4%) for the liver; 0 + 1/4 (25.0%) for the abdominal lymph nodes; 0 + 1/2 (50.0%) for the superficial lymph nodes; 0 + 1/2 (50.0%) for the bones; and 0 + 1/1 (100%) for the lung. The median duration of the response was 3.7 months (range between 1.5 and 8.2+) and the median duration of survival 5.1+ months (range between 2.2+ and 13.3+). At the same time, the hematological side effects of both leukocytopenia and hypohemoglobinemia were seen in 43.8% of the cases. Non-hematological side effects included alopecia in 18.8% and nausea/vomiting in 12.5%. There was no case of discontinuation due to side effects. It was concluded that the therapy with MMC, ADM, CDDP, etoposide and 5'DFUR (MAC-VD therapy) proved to be a very promising drug regimen in the treatment of stomach cancer with high rates of response and is expected to be a step forward in the establishment of interdisciplinary treatment.

[Vincristine, adriamycin, mitomycin-C and UFT (VAM-UFT) therapy in progressive or recurrent breast cancer].

Since June 1984, 23 cases of progressive or recurrent breast cancers were treated with combination chemotherapy of VAM-UFT consisting of vincristine, adriamycin, mitomycin C and UFT. Clinical effects of VAM-UFT therapy were 3 CR, 12 PR, and the response rate was 65.2%. Its effective interval was 3 months. But the patients treated with over 4 cycles of VAM-UFT therapy showed an 85% response rate, with a 5-month effective interval. In each patient's background, a shorter disease free interval tended to be more highly effective, but other factors were not significant. Scirrhous carcinoma of pathology evidenced slightly high response rate. Compared with the survival time of patients treated with under 3 cycles and over 4 cycles of this therapy, the latter was significantly longer. Toxicity involved leukocytopenia (74%), thrombocytopenia (22%), anemia (30%), alopecia (91%), nausea and vomiting (87%) and stomatitis (35%), but cases in which the treatment was stopped were not observed. Therefore VAM-UFT therapy had a highly therapeutic effect, reflected in an 85% response rate, for progressive or recurrent breast cancers.

[Study of chemotherapy in the field of internal medicine--clinical experience with SF-SP].

UNLABELLED: An SF-SP Tegafur spansule preparation was administered to 26 patients with advanced cancer (24 evaluable), and the clinical effectiveness and toxicity were studied. In most of cases, daily dosages of 800 mg were administered in two parts, in a few cases, daily dosages of 1,000 mg or 1,200 mg were given. Clinical effectiveness: The evaluation of effectiveness was based on the Koyama-Saito group criteria. Of the 24 evaluable cases, PR was observed in 3 cases of gastric cancer, one of colon cancer, and one of liver cancer, a total of 5 cases (20.8%). In these 5 cases the daily dosage was 800 mg, and the median duration of PR was 51 days. TOXICITY: TOXICITY was observed in 3 (11.5%) of the 26 cases.