Protocol for the ASTRO study (SSOP-01): a multicentre prospective cohort study investigating adverse events based on electronic patient-reported outcomes in patients with breast cancer after adjuvant chemotherapy

INTRODUCTION

Symptom-related adverse events associated with perioperative chemotherapy in patients with breast cancer include short-term adverse events such as nausea and vomiting. However, changes in the severity and duration of prolonged symptom-related adverse events have not been fully investigated. We present a protocol of a study that aims to clarify the prevalence of symptom-related adverse events in patients with breast cancer 1 year after neoadjuvant or adjuvant chemotherapy using an electronic patient-reported outcomes (ePRO) system.

METHODS AND ANALYSIS

This multicentre prospective observational cohort study will include patients with breast cancer who have received preoperative or postoperative adjuvant chemotherapy. The final injection date of the cytotoxic agent will be the study initiation date. Patients will report every 2 weeks from the initiation date to 12 weeks and every 4 weeks from 12 weeks to 1 year, and they can enter this information into the ePRO system from anywhere. The primary outcome will be the prevalence of symptom-related adverse events according to the ePRO system 1 year after the date of the last injection of the cytotoxic drug used in neoadjuvant or adjuvant chemotherapy for breast cancer. To increase multi-institutional enrolment, two cohorts will be included. Cohort 1 will comprise patients with acquisition of baseline patient information regarding preoperative chemotherapy and presurgery characteristics. Cohort 2 will comprise patients without acquisition of baseline patient information. The target sample size is ≥250 per year.

ETHICS AND DISSEMINATION

The study protocol has been approved by the ethics committee at each participating institution. The results will be presented at major national and international conferences and submitted to peer-reviewed journals.

TRIAL STATUS

Registration was started in October 2021. By August 2022, a total of 132 participants were enrolled. Follow-up will be continued through December 2024.

TRIAL REGISTRATION NUMBER

UMIN000045422.

Preoperative steroid for enhancing patients' recovery after head and neck cancer surgery with free tissue transfer reconstruction: protocol for a phase III, placebo-controlled, randomised, double-blind study (J-SUPPORT 2022, PreSte-HN Study)

INTRODUCTION

There is no established methodology for the perioperative management of head and neck cancer surgery and free tissue transfer reconstruction (HNS-FTR). A single dose of corticosteroid administered immediately before surgery has been shown to reduce postoperative pain and nausea/vomiting after some types of surgery. However, the efficacy of this strategy has not been demonstrated in HNS-FTR, and the increased risk of infectious complications associated with its use cannot be ruled out. This phase III, placebo-controlled, randomised, double-blind, comparative, multicentre study seeks to determine if preoperative administration of corticosteroid hormone has an adjunctive effect in terms of reducing pain and nausea/vomiting after surgery and improving the quality of postoperative recovery.

METHODS AND ANALYSIS

Using the minimisation method, patients undergoing HNS-FTR are currently being recruited and randomly assigned to a study arm at a 1:1 allocation rate. The study treatment arm consists of 8.0 mg of dexamethasone phosphate dissolved in 100 mL of saline administered as a single dose by intravenous infusion. These treatments will be administered in a double-blind fashion. All patients will receive perioperative care according to the common multicentre enhanced recovery after surgery programme. The primary endpoint is the quality of postoperative recovery, as determined by the area under the curve (AUC) for total score on the Japanese version of the Quality of Recovery Score (QOR-40J) on postoperative days 2 and 4. The point estimate and CI for the difference in the AUC between the groups on postoperative days 2 and 4 will be calculated.

ETHICS AND DISSEMINATION

The study will be performed in accordance with the Declaration of Helsinki and Japan's Clinical Trials Act. The study protocol was approved by the Certified Review Board of National Cancer Center Hospital East (Reference K2021004).

TRIAL REGISTRATION NUMBER

The study was registered in the Japan Registry of Clinical Trials (jRCTs031210593; V.3.0, November 2021, available at https://jrct.niph.go.jp/en-latest-detail/jRCTs031210593).

Abstract P5-05-08: Molecular cross-talk between retinoic acid and NOTCH1 signaling pathways: Role in triple negative breast cancer

Triple Negative Breast Cancer (TNBC) represents 10-20% of all breast cancers and it is characterized by poor prognosis and high recurrence rate. The heterogeneity of the disease and the absence of well-defined molecular targets have so far challenged successful therapeutic strategies. NOTCH1 has been found to act as a driver oncogene in a small subset of TNBC characterized by constitutive activation of the protein, acting as a transcription factor. Preclinical studies support an anti-tumor activity of All-Trans Retinoic Acid (ATRA) in specific subsets of breast cancer.

By screening a large panel of breast cancer cell lines recapitulating the heterogeneity of TNBC we identify a specific subset sensitive to the anti-proliferative activity of ATRA. These cell lines (N-TNBC cell lines) are characterized by a Notch1 intragenic fusion transcript conferring gain of function activity to the protein. Indeed, sequence analysis reveals that the cell lines harbor an interstitial deletion in the NOTCH1 gene encompassing the negative regulatory region (NRR) domain. These cell lines depend on Notch active signaling for their proliferation since their cell growth is impaired by Notch inhibitors (γ-secretase inhibitors, e.g. DAPT, PF-3084014). Proliferation assays reveal that ATRA and γ-secretase inhibitors act synergistically in inhibiting cancer cell growth in N-TNBC cell lines suggesting the existence of a cross talk between the molecular pathways engaged by retinoic acid and NOTCH1.

By using retinoic acid receptors (RARs) agonists and antagonists as well as RAR specific silencing experiments we identify RARα as the retinoic acid receptor responsible of the anti-proliferation activity of ATRA in N-TNBC cell lines. In particular N-TNBC cell lines respond to RARα activation by inducing high amounts of the onco-supressor protein RARβ. This feature is unique in ATRA sensitive TNBC cell lines and does not occur in ATRA sensitive luminal cell lines arguing for the existence of a retinoic acid specific mechanism of action in N-TNBC. Since RARs act as transcription factors inside the cells, to gain insights into the molecular pathway at the basis of the observed ATRA/NOTCH1 cross talk, we performed RNAseq analysis of ATRA and/or DAPT treated N-TNBC cells. Gene set enrichment analysis reveal that ATRA is able to directly affect NOTCH1 transduction pathway by modulating the expression of NOTCH1 target genes. In particular, in two out of three N-TNBC cell lines ATRA directly inhibits the NOTCH1 expression at a transcriptional level and its downregulation is increased by ATRA/DAPT combinations. Pathway analysis has allowed the identification of putative molecular hubs responsible for the synergistic effects observed and therefore likely at the basis of the crosstalk between ATRA/NOTCH pathways. These findings are of clinical interest since both the retinoid and NOTCH signaling display crucial physiologic activities and their pleiotropic effects could impinge on the success of therapeutic options based on their pathway modulation.

The newly discovered specificity of ATRA action in the context of NOTCH1 addicted TNBC provides new tools for the identification of patients candidates benefitting from strategies targeting the ATRA/NOTCH axis.

Citation Format: Paroni G, Zanetti A, Bolis M, Vallerga A, Troiani M, Fratelli M, Kurosaki M, Terao M, Garattini E. Molecular cross-talk between retinoic acid and NOTCH1 signaling pathways: Role in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-05-08.

Abstract P2-02-15: All-trans retinoic acid perturbs the lipidomic profiles of luminal breast cancer cells characterized by sensitivity to the anti-proliferative activity of the retinoid

Background: All-trans retinoic acid (ATRA) is the active metabolite of vitamin A and a promising agent in the prevention and treatment of breast cancer. We recently demonstrated that approximately 70% of estrogen-receptor-positive (ER+) breast cancer cell lines and primary tumors are sensitive to the anti-proliferative effects of ATRA (1,2). In contrast only 10-20% of the HER2-positive and triple-negative counterparts respond to the retinoid. The significance of lipids in the growth, progression and drug sensitivity of specific types of solid tumors, including breast cancer, is largely overlooked. In particular the role, if any, of specific lipids in the anti-tumor action of ATRA in breast cancer has never been studied.

Aims and Approach: The principal aim of the present work was to evaluate the specific perturbations induced by ATRA on the homeostasis of lipids in breast cancer cells characterized by sensitivity to the anti-proliferative action of the retinoid. To this purpose, we took a high-throughput approach and defined the lipidomic profiles of 16 breast cancer cell lines in basal conditions and following challenge with ATRA (1 μM) for 48 hours. The panel consisted of eight cell lines characterized by a luminal phenotype and eight cell lines with a basal phenotype. Four ATRA-sensitive cell lines (SKBR3, HCC1500, CAMA1 and MDAMB361) and 4 ATRA-resistant counterparts (HCC202, MDAMB175VII, ZR75.1 and HCC1419) were included in the luminal group. Similarly, the basal group contained 4 ATRA-sensitive (HCC1599, MB157, MDAMB157 and Hs578T) and 4 ATRA-resistant (MDAMB231, CAL851, HCC1187 and MDAMB436) cell types.

Results: Using Lipostar, a unique and recently developed software for high-throughput LC-MS lipidomics analysis (3), we identified lipid species whose levels were modified by ATRA in each cell line. This resulted in the generation of a lipid fingerprint consisting of 530 elements. We observed that ATRA reduced the amounts of cardiolipins in luminal and ATRA-sensitive breast cancer cell lines specifically. Similar effects were not observed in luminal and ATRA-resistant cells. ATRA-dependent reduction in the amounts of cardiolipins were never observed in basal cells, regardless of their sensitivity to the retinoid. Given the role played by cardiolipins in the homeostasis of the mitochondria, we evaluated the action of ATRA on the functional activity of these organelles in the luminal and ATRA-sensitive or ATRA-resistant cell lines. In SKBR3 and the other sensitive cell lines, we observed that ATRA modulated mitochondria-dependent oxygen consumption and ATP production. These effects were accompanied by an increase in mitochondrial membrane fluidity, which is consistent with the effects exerted by ATRA on the cellular content of cardiolipins. ATRA-dependent action on cardiolipins and mitochondrial homeostasis precedes maximal growth inhibition. The results provide new insights on the mechanisms underlying the anti-tumor action of ATRA.

References : 1) Centritto F. et al. EMBO Mol Med. 2015 Jul;7(7):950-72. 2) Bolis M et al.. Ann Oncol. 2017 Mar 1;28(3):611-621. 3) Goracci, L. et al., Anal Chem 2017, 89 (11), 6258-6265.

Citation Format: Terao M, Celestini V, Kurosaki M, Vallerga A, Bolis M, Fratelli M, Paroni G, Di Veroli A, Cruciani G, Goracci L, Garattini E. All-trans retinoic acid perturbs the lipidomic profiles of luminal breast cancer cells characterized by sensitivity to the anti-proliferative activity of the retinoid [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-02-15.

Abstract P5-05-09: Systemic perturbations induced by all-trans retinoic acid in the gene-expression profiles of sixteen breast cancer cell lines characterized by sensitivity and resistance to the anti-proliferative effects of the retinoid

Background: All-trans retinoic acid (ATRA) is a promising agent in the treatment of breast cancer. In view of ATRA-based therapeutic strategies aimed at the personalized treatment of mammary tumors, we recently demonstrated that approximately 70% of estrogen-receptor-positive (ER+) breast cancer is sensitive to the anti-proliferative effects of ATRA (1). In contrast only 10-20% of the HER2-positive and triple-negative counterparts respond to the retinoid. On the basis of these data and the available basal gene-expression profiles of breast cancer cell lines and primary tumors, we developed a model consisting of 21 genes (ATRA-21) which correctly predicts ATRA-sensitivity in the context of breast cancer (2).

Aims and Approach: The present study is aimed at getting insights into the molecular mechanisms underlying the anti-tumor action of ATRA in the specific subsets of breast cancer identified. In addition, we intend to determine specific genes and gene-networks modulated by ATRA which may represent pharmacological targets for the design of rational combinations between the retinoid and unrelated therapeutic agents to be used in the personalized treatment of breast cancer. A final goal is the identification of potential bio-markers of the anti-tumor response to ATRA to be used in the clinics. To address all these points, we performed deep-sequencing experiments on a panel of sixteen cell lines recapitulating the heterogeneity of the breast cancer phenotype and characterized for their anti-proliferative response to ATRA.

Panel of Breast cancer cell lines and characteristicsCell linePhenotypeClassATRA-scoreATRA-sensitivitySKBR3LUMINALHER2+1.0yesHCC1500LUMINALER+0.7yesCAMA1LUMINALER+0.7yesMDAMB361LUMINALHER2+0.6yesHCC202LUMINALHER2+0.2noMDAMB175VIILUMINALER+0.2noZR751LUMINALER+0.1noHCC1419LUMINALHER2+0.1noHCC1599BASALTN1.0yesMB157BASALTN0.3yesMDAMB157BASALTN0.2yesHS578TBASALTN0.2yesMDAMB231BASALTN0.0noCAL851BASALTN0.0noHCC1187BASALTN0.0noMDAMB436BASALTN0.0noATRA-score = ATRA sensitivity index, the higher the score the higher is the sensitivity to ATRA. ER+ = estrogen-receptor-positive cell line. HER2+ = Her2-positive cell line.

Results: We exposed each cell line to ATRA (1 μM) for 24 hours and extracted total RNA which was subjected to deep sequencing. The global gene-expression data were analyzed with a number of complementary bio-informatic tools which resulted in the identification of approximately 100 genes whose expression is up- or down-regulated specifically in ATRA-sensitive luminal and/or basal cell lines. Pathway and gene-network analysis indicate a strong enrichment in the up-regulation of genes involved in the pathways modulated by interferons. These last results are consistent with the idea that ATRA exerts a strong immuno-modulatory action in breast cancer cells and represents proof of principle for the evaluation of combinations between the retinoid and check-point inhibitors in the treatment of breast cancer.

References: 1) Centritto F. et al. EMBO Mol Med. 2015 Jul;7(7):950-7. 2) Bolis M et al.. Ann Oncol. 2017 Mar 1;28(3):611-621.

Citation Format: Garattini E, Bolis M, Vallerga A, Fratelli M, Paroni G, Zanetti A, Kurosaki M, Gianni' M, Celestini V, Terao M. Systemic perturbations induced by all-trans retinoic acid in the gene-expression profiles of sixteen breast cancer cell lines characterized by sensitivity and resistance to the anti-proliferative effects of the retinoid [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-05-09.

Network-guided modeling allows tumor-type independent prediction of sensitivity to all-trans-retinoic acid

Background

All-trans-retinoic acid (ATRA) is a differentiating agent used in the treatment of acute-promyelocytic-leukemia (APL) and it is under-exploited in other malignancies despite its low systemic toxicity. A rational/personalized use of ATRA requires the development of predictive tools allowing identification of sensitive cancer types and responsive individuals.

Materials and methods

RNA-sequencing data for 10 080 patients and 33 different tumor types were derived from the TCGA and Leucegene datasets and completely re-processed. The study was carried out using machine learning methods and network analysis.

Results

We profiled a large panel of breast-cancer cell-lines for in vitro sensitivity to ATRA and exploited the associated basal gene-expression data to initially generate a model predicting ATRA-sensitivity in this disease. Starting from these results and using a network-guided approach, we developed a generalized model (ATRA-21) whose validity extends to tumor types other than breast cancer. ATRA-21 predictions correlate with experimentally determined sensitivity in a large panel of cell-lines representative of numerous tumor types. In patients, ATRA-21 correctly identifies APL as the most sensitive acute-myelogenous-leukemia subtype and indicates that uveal-melanoma and low-grade glioma are top-ranking diseases as for average predicted responsiveness to ATRA. There is a consistent number of tumor types for which higher ATRA-21 predictions are associated with better outcomes.

Conclusions

In summary, we generated a tumor-type independent ATRA-sensitivity predictor which consists of a restricted number of genes and has the potential to be applied in the clinics. Identification of the tumor types that are likely to be generally sensitive to the action of ATRA paves the way to the design of clinical studies in the context of these diseases. In addition, ATRA-21 may represent an important diagnostic tool for the selection of individual patients who may benefit from ATRA-based therapeutic strategies also in tumors characterized by lower average sensitivity.

Hepatitis B surface antigen reduction by switching from long-term nucleoside/nucleotide analogue administration to pegylated interferon

Hepatitis B surface antigen (HBsAg) reduction during nucleoside/nucleotide analogue (NA) therapy is slow and an alternative strategy for patients receiving ongoing NA to facilitate HBsAg reduction is required. We investigated whether switching to pegylated interferon (PEG-IFN) after long-term NA administration enhances HBsAg reduction. Forty-nine patients who switched from long-term NA to 48 weeks of PEG-IFN alfa-2a were studied. The mean duration of previous NA was 48 months (sequential group). A total of 147 patients who continued NA and matched for baseline characteristics were analysed for comparison (NA continuation group). The treatment response was defined as HBsAg reduction ≥1.0 logIU/mL at the end of PEG-IFN. HBsAg reduction at week 48 was 0.81±1.1 logIU/mL in the sequential group, which was significantly higher than that in the NA continuation group (0.11±0.3 logIU/mL, P < .001). The treatment response was achieved in 29% and 2% of the sequential group and NA continuation group (P < .001), and the odds ratio of sequential therapy for the treatment response was 19 compared with the NA continuation (P < .001). In patients tested positive for hepatitis B e antigen (HBeAg), HBeAg seroconversion was higher in the sequential group (44% vs 8%, P < .001). In HBeAg-negative patients, only patients in the sequential group achieved HBsAg loss. No patient needed to resume NA administration because of HBV DNA increase accompanied by alanine aminotransferase flares. In summary, sequential therapy with PEG-IFN after long-term NA enhances the reduction of HBsAg and may represent a treatment option to promote HBsAg loss.

Effects of HLA-DPB1 genotypes on chronic hepatitis B infection in Japanese individuals

Significant associations of HLA-DP alleles with chronic hepatitis B (CHB) infection are evident in Asian and Arabian populations, including Japanese, Han Chinese, Korean, and Saudi Arabian populations. Here, significant associations between CHB infection and five DPB1 alleles (two susceptibility alleles, DPB1(*) 05:01 and (*) 09:01, and three protective alleles, DPB1(*) 02:01, (*) 04:01, and (*) 04:02) were confirmed in a population comprising of 2582 Japanese individuals. Furthermore, odds ratios for CHB were higher for those with both DPB1 susceptibility alleles than for those with only one susceptibility allele; therefore, effects of susceptibility alleles were additive for risk of CHB infection. Similarly, protective alleles showed an additive effect on protection from CHB infection. Moreover, heterozygotes of any protective allele showed stronger association with CHB than did homozygotes, suggesting that heterozygotes may bind a greater variety of hepatitis B-derived peptides, and thus present these peptides more efficiently to T-cell receptors than homozygotes. Notably, compound heterozygote of the protective allele (any one of DPB1*02:01, *04:01, and *04:02) and the susceptible allele DPB1*05:01 was significantly associated with protection against CHB infection, which indicates that one protective HLA-DPB1 molecule can provide dominant protection. Identification of the HLA-DPB1 genotypes associated with susceptibility to and protection from CHB infection is essential for future analysis of the mechanisms responsible for immune recognition of hepatitis B virus antigens by HLA-DPB1 molecules.

ITPA genetic variants influence efficacy of PEG-IFN/RBV therapy in older patients infected with HCV genotype 1 and favourable IL28B type

Inosine triphosphatase (ITPA) genetic variants are strongly associated with ribavirin (RBV)-induced anaemia during pegylated interferon (PEG-IFN) plus RBV therapy. However, the treatment efficacy of ITPA genetic variants has not been fully explored. We enrolled 309 individuals infected with hepatitis C virus genotype 1, who were treated with PEG-IFN plus RBV for 48 weeks. The ITPA SNP: rs1127354 and IL28B SNP: rs8099917 were genotyped. We examined the risk factors for severe anaemia up to week 12 after the start of treatment and treatment efficacy. The incidence of severe anaemia, ≥ 3 g/dL reduction or <10 g/dL of haemoglobin (Hb) up to week 12, was more frequent in patients with CC at rs1127354 [65% (145/224), 33% (73/224)] than in those with CA/AA [25% (21/85), 6% (8/85)] (P < 0.0001). ITPA genotype, pretreatment Hb level and age were independent predictive factors for severe anaemia: Hb < 10 g/dL. In IL28B favourable type, the sustained virologic response rate was higher in ≥ 60-year-old patients with CA/AA than in those with CC [71% (22/31) vs 40% (26/65), P = 0.005], although there was no significant difference in treatment efficacy according to ITPA genetic variants in the <60-year-old patients. The proportion of patients administered ≥ 80% of the dosage of RBV was significantly higher in the patients with CA/AA than in those with CC (P = 0.025), resulting in a lower relapse rate. In conclusion, ITPA genetic variants were associated with severe RBV-induced anaemia and could influence the efficacy of PEG-IFN plus RBV treatment among elderly patients with IL28B favourable type.

Noninvasive estimation of fibrosis progression overtime using the FIB-4 index in chronic hepatitis C

The FIB-4 index is a simple formula to predict liver fibrosis based on the standard biochemical values (AST, ALT and platelet count) and age. We here investigated the utility of the index for noninvasive prediction of progression in liver fibrosis. The time-course alteration in the liver fibrosis stage between paired liver biopsies and the FIB-4 index was examined in 314 patients with chronic hepatitis C. The average interval between liver biopsies was 4.9 years. The cases that showed a time-course improvement in the fibrosis stage exhibited a decrease in the FIB-4 index, and those that showed deterioration in the fibrosis stage exhibited an increase in the FIB-4 index with a significant correlation (P < 0.001). Increase in the ΔFIB-4 index per year was an independent predictive factor for the progression in liver fibrosis with an odds ratio of 3.90 (P = 0.03). The area under the receiver operating characteristic curve of the ΔFIB-4 index/year for the prediction of advancement to cirrhosis was 0.910. Using a cut-off value of the ΔFIB-4 index/year <0.4 or ≥ 0.4, the cumulative incidence of fibrosis progression to cirrhosis at 5 and 10 years was 34% and 59%, respectively in patients with the ΔFIB-4 index/year ≥0.4, whereas it was 0% and 3% in those with the ΔFIB-4 index/year <0.4 (P < 0.001). In conclusion, measurement of the time-course changes in the FIB-4 index is useful for the noninvasive and real-time estimation of the progression in liver fibrosis.

Pharmacokinetics and enhanced PKR response in patients with chronic hepatitis C treated with pegylated interferon alpha-2b and ribavirin

This study investigated the molecular and pharmacokinetic mechanisms of the enhanced antiviral efficacy associated with pegylated interferon (PEG-IFN) alpha-2b and ribavirin. The study involved comparing the expression of serial double-stranded RNA-activated protein kinase (PKR) before and during treatment in 26 PEG-IFN alpha-2b and 26 conventional IFN alpha-2b recipients matched for age, body weight and dose of ribavirin. The pharmacokinetics of PEG-IFN alpha-2b and ribavirin was analysed in 15 of the 26 PEG-IFN recipients. There was a rapid increase in PKR expression in both treatment groups, although expression from day 2 onwards was maintained at a significantly higher level in the PEG-IFN recipients (P < 0.05). C(max) of PEG-IFN occurred 12-48 h after the initial administration, with t(1/2) and C(min) being 49 h and 190 pg/mL, respectively. In contrast to ribavirin, accumulation of PEG-IFN was minimal. There was no association between serum PEG-IFN and ribavirin levels and virological response. Although baseline expression of PKR before treatment was marginally higher in nonresponders (NRs), from day 2 onwards, sequential PKR expression in response to PEG-IFN was higher in sustained viral responders compared with the NRs (P < 0.05). Significant correlations were found between kinetics of PKR expression and viral decline rates in each phase of hepatitis C virus dynamics (first phase, r = 0.67, P = 0.0006; second phase, r = 0.67, P = 0.001). In conclusion, improvement in pharmacokinetics following pegylation led to higher intracellular PKR expression, which was associated with enhanced virological efficacy of PEG-IFN-based combination therapy. The concentrations of both ribavirin and PEG-IFN alpha-2b were not associated with viral response and PKR expression.

Expressional screening of interferon-stimulated genes for antiviral activity against hepatitis C virus replication

Type-I interferons (IFNs) and the interferon-stimulated genes (ISGs) play a major role in antivirus responses against hepatitis C virus (HCV) infection. In this study, we studied expression profiles of ISGs in cells supporting subgenomic HCV replication (Huh7/Rep), and screened their activities to suppress HCV replication. Real-time PCR analyses showed that the expression levels of 23 ISGs were significantly lower in Huh7/Rep than naive Huh7 cells due to transcriptional suppression of the interferon-stimulated response element (ISRE). Furthermore, the expression level of ISGs was also decreased in the cured Huh7 cells in which replicon had been eliminated (cHuh7), indicating adaptation of the cells to support HCV replication by downregulating ISGs. On the other hand, expression of HCV replicon was significantly suppressed by overexpression of several ISGs including PKR, MxA, IRF-9, GBP-1, IFI-6-16, IFI-27, 25OAS and IRF-1. Knock down of GBP-1, IFI-6-16 and IFI-27 by short hairpin RNA resulted in increase of HCV replication. Thus, we conclude that downregulation of ISG expression is required in the host cells supporting HCV replication and that several ISGs directly suppress HCV replication. The search for ISGs that regulate HCV replication may help to elucidate the cellular antiviral defence mechanisms against HCV infection.

Site-specific mutation of the interferon sensitivity-determining region (ISDR) modulates hepatitis C virus replication

The number of amino acid substitutions in the interferon sensitivity-determining region (ISDR) in the nonstructural 5A (NS5A) gene of hepatitis C virus (HCV) is closely associated with the interferon (IFN) response and viral load. Several HCV replicon-based studies have reported that ISDR sequences had an influence on viral replication in vitro. However, it is unclear as to how different ISDR sequences affect HCV replication. Various clinically observed ISDR sequences were introduced into HCV replicons and their contribution to viral replication was investigated using a colony formation assay and/or a transient replication assay. A mapping study of the ISDR was performed to identify the amino acid positions that critically affect replication. While no colonies were formed in the colony formation assay using HCV replicons with few mutations (0, 1 and 3) in the ISDR, numerous colonies (>200) appeared when using constructs with six mutations. Introduction of various distinct ISDR sequences with multiple mutations resulted in replication enhancement in transient assays. A mapping study identified several specific sites in the ISDR that critically affected replication, including codon 2209 which, in patients, was closely associated with a strong response to IFN. ISDR sequences associated with a clinical IFN response and viral load modulated the replication of HCV replicons, suggesting the importance of the ISDR sequence in HCV infection.

Characteristic sequence changes of hepatitis C virus genotype 2b associated with sustained biochemical response to IFN therapy

In hepatitis C virus (HCV) genotype 2b infection, viral eradication (sustained viral response; sVR) is obtained in about 40% by interferon monotherapy, whereas a considerable proportion of non-sVR patients exhibit sustained biochemical response (sBR) showing normal biochemical values despite persistent viraemia. However, the mechanism of sBR has not yet been established. In this study, we analysed serial changes in full-length sequences of HCV genotype 2b before and after interferon (IFN) therapy in five patients with sBR and five with no response (NR; persistent viraemia and abnormal biochemical values after IFN therapy). The overall substitution rate of amino acids in the full-length HCV genome was higher in the sBR group than in the NR group [2.22 +/- 0.48 (10(-3) changes/site/year) vs 1.04 +/- 0.30: P = 0.002]. When the genetic changes were analysed for individual HCV proteins, the sBR group had significantly higher substitution rates of amino acid in NS4A [8.82 +/- 2.80 (10(-3) changes/site/year) vs 0: P = 0.001]. These amino acid changes in sBR were mainly located in the binding motifs of HLA class I molecules including those frequently found in the Japanese population. These results demonstrated that the greater amino acid changes of HCV arising during interferon therapy are associated with the establishment of sBR. Although functional significance of these changes awaits further investigation, the finding that amino acid changes in NS4A in sBR patients are mainly located in the HLA class I binding motifs illustrated the potential roles of the escape mutations of HCV genome from CTLs in the decreasing activities of hepatitis in sBR.

Introduction of NS5A mutations enables subgenomic HCV replicon derived from chimpanzee-infectious HC-J4 isolate to replicate efficiently in Huh-7 cells

Hepatitis C virus (HCV) subgenomic replicon has been reported to replicate efficiently and continuously in human hepatoma Huh-7 cells. To extend the previous results to other isolated HCV clones, we constructed another HCV replicon from HC-J4, one of chimpanzee-infectious HCV clones. An HCV replicon derived from HC-J4 (RpJ4) consists of HCV-5' untranslated region, neomycin phosphotransferase gene, the encephalomyocarditis virus internal ribosomal entry site, HCV nonstructural region, NS3 to NS5B, and HCV-3' untranslated region. The adaptive mutations known to be required for HCV-Con1 replicon were introduced in RpJ4 replicon, aa.(amino acids number according to HC-J4) 2197 serine to proline, deletion of serine at aa.2201, and aa.2204 serine to isoleucine (RpJ4-S2197P, RpJ4-S22001del, and RpJ4-S2204I). RpJ4/ISDR mutant and RpJ4-S2201del/ISDR mutant were also constructed by introducing six amino acid mutations into the interferon sensitivity determining region (ISDR). After transfection into Huh-7 cells and G418 selection, RpJ4 and RpJ4/ISDR mutants did not produce any colony. In contrast, G418-resistant cells were transduced efficiently by RpJ4-S2197P, RpJ4-S2204I, RpJ4-S2201del and RpJ4-S2201del/ISDR mutant, with the RpJ4-S2201del/ISDR mutant being most efficient. Hence the HCV replicon derived from HC-J4 can replicate efficiently following the introduction of adaptive mutations into the upstream region of ISDR. Moreover, additional introduction of mutations into ISDR further enhanced its replication. These findings demonstrate that the genetic structure of the NS5A domain is critical in HCV replications.

Differential gene-expression profiles associated with gastric adenoma

Gastric adenomas may eventually progress to adenocarcinomas at varying rates. The purpose of the present study was to identify gene-expression profiles linked to the heterogeneous nature of gastric adenoma as compared to adenocarcinoma. Suppression subtractive hybridisation analysis was performed to extract relevant genes from two cases of low- and high-grade gastric adenomas. The identified genes were quantified by RT-PCR in 14 low-grade adenoma, nine high-grade adenoma and nine adenocarcinoma samples, followed by hierarchical clustering analysis to separate tumours into groups according to their gene-expression profiles. Nine genes previously implicated in carcinogenesis in a variety of organs, including three genes related to gastric adenocarcinoma, were identified. The overexpression of these genes in gastric adenoma has not been reported previously. The clustering analysis of these nine genes across 32 cases identified three groups, one of which consisted primarily of adenocarcinomas, whereas the other two groups consisted of adenomas. One group of adenomas, characterised by larger tumour size, exhibited gene-expression profiles of an intestinal cell lineage implicated in the pathogenesis of an intestinal-type gastric adenocarcinoma. Another adenoma group consisting of low-grade adenomas with smaller tumour size exhibited a unique expression profile. In conclusion, clustering analysis of expression profiles using a limited number of genes may serve as molecular markers for gastric adenoma with different biological properties. Although the prognostic values of these gene-expression profiles need to be evaluated in further follow-up study of adenoma cases, these findings add new insights to (a) our understanding of the pathogenesis of gastric tumours, (b) the development of specific tumour markers for clinical practice, and (c) the design of novel therapeutic targets.

Pituitary tumors in the elderly

The present study was designed to investigate the incidence and immunohistochemical characteristics of pituitary tumors in the elderly. In our surgical collection of 1925 cases, we examined tumor tissue from 15 patients over 80 years of age. Pituitaries obtained at routine autopsies from 692 subjects over 80 years of age were also investigated. Of the 15 surgical cases studied, the majority of patients presented with chiasmatic syndromes, likely caused by macroadenomas. Gonadotroph adenomas were the most frequently diagnosed tumor type, followed by null-cell adenomas and oncocytomas. There is only one case with GH cell adenoma. Among 692 autopsy cases, 79 (11.4%) pituitaries were found to contain adenomas in the anterior lobe. In one pituitary, two separate adenomas were detected, hence the number of adenomas in our material was 80. All autopsy cases were microadenomas except one. The mean diameter of adenomas was 2.2 mm. ACTH cell adenomas were the most frequently diagnosed tumor type, followed by PRL cell adenomas and null cell adenomas. The occurrence of pituitary adenomas discovered after routine autopsy in the elderly was common, although these tumors were not found frequently in surgical cases over 80 years of age. Our immunohistochemical study revealed that many tumors contained one or more than one anterior pituitary hormone, although almost all pituitary adenomas were considered to be clinically inactive in surgical and autopsy cases.

Immunohistochemical localisation of cytokeratins in craniopharyngioma

BACKGROUND

Although craniopharyngiomas have been examined in several microscopical studies to date, immunohistochemical analysis has not been sufficient.

METHOD

In addition to the routine haematoxylin and eosin staining, 38 cases of intra- and/or supra-sellar craniopharyngioma, including 34 adamatinomatous and 4 squamous papillary types, were studied using immunohistochemistry for expression of four types of cytokeratin.

FINDINGS

Histological examination found epithelial cells in 26 of 38 (68.40%) cases. However, cytokeratins were demonstrated in 35 of 38 (92.1%) cases. The remaining 3 cases without demonstration of epithelial cell nests were supposed to be adamantinomatous craniopharyngiomas based on the findings in the stroma. In 31 of 34 adamantinomatous craniopharyngioma cases, the epithelium was detected by immunostaining for cytokeratins. The epithlieum expressed 56 kDa (KL-1) and 40 kDa (cytokeratin 19) cytokeratins with similar staining patterns and intensities. The staining intensity of 54 kDa cytokeratin (cytokeratin 7) was similar to that of the high molecular weight cytokeratin (keratin M-903). However, in many cases (15 of 27), immunoreactivity of cytokeratin 7 was not demonstrated in an outer palisaded basal layer. In all 4 squamous papillary craniopharyngiomas, moderate staining with cytokeratin 7 appeared in the superficial layer, whereas basal or mid-zone epithelial cells were negative for cytokeratin 7. The basal layer stained negatively for KL-1, as well as cytokeratin 7.

INTERPRETATION

Immunostaining for cytokeratin is valuable in the investigation of craniopharyngioma, especially when specimens contain only a small or questionable part of epithelium. Most notably, KL-1 or cytokeratin 7 stainings are suitable for analyzing these tumours, with special reference to histological subtypes.

Purification of the aldehyde oxidase homolog 1 (AOH1) protein and cloning of the AOH1 and aldehyde oxidase homolog 2 (AOH2) genes. Identification of a novel molybdo-flavoprotein gene cluster on mouse chromosome 1

We report the cloning of the AOH1 and AOH2 genes, which encode two novel mammalian molybdo-flavoproteins. We have purified the AOH1 protein to homogeneity in its catalytically active form from mouse liver. Twenty tryptic peptides, identified or directly sequenced by mass spectrometry, confirm the primary structure of the polypeptide deduced from the AOH1 gene. The enzyme contains one molecule of FAD, one atom of molybdenum, and four atoms of iron per subunit and shows spectroscopic features similar to those of the prototypic molybdo-flavoprotein xanthine oxidoreductase. The AOH1 and AOH2 genes are 98 and 60 kilobases long, respectively, and consist of 35 coding exons. The AOH1 gene has the potential to transcribe an extra leader non-coding exon, which is located downstream of exon 26, and is transcribed in the opposite orientation relative to all the other exons. AOH1 and AOH2 map to chromosome 1 in close proximity to each other and to the aldehyde oxidase gene, forming a molybdo-flavoenzyme gene cluster. Conservation in the position of exon/intron junctions among the mouse AOH1, AOH2, aldehyde oxidase, and xanthine oxidoreductase loci indicates that these genes are derived from the duplication of an ancestral precursor.

Overexpression of interferon gamma-inducible protein 10 in the liver of patients with type I autoimmune hepatitis identified by suppression subtractive hybridization

OBJECTIVE

To clarify gene expression profiles in the liver may elucidate the pathogenesis of type I autoimmune hepatitis (AIH). Using suppression subtractive hybridization (SSH), we identified genes overexpressed in the liver of AIH.

METHODS

A small liver biopsy sample from a patient with definite AIH was available to be analyzed in our system. By mixing cDNA synthesized from this sample as a 'tester' and cDNA from a normal liver as a 'driver,' we subtracted cDNA to enrich genes overexpressed in AIH. After polymerase chain reaction (PCR) amplification and subcloning, we identified subtracted genes by sequencing 50 randomly selected clones.

RESULTS

Only one cDNA fragment, which is identical to interferon inducible protein 10 (IP-10), was overexpressed by > 10 times in the liver of AIH, as compared with control. We confirmed IP-10 overexpression in all eight patients with AIH by reverse transcription PCR. Immunohistochemical analysis demonstrated increased IP-10 expression in hepatocytes in the liver of AIH. Reverse transcription PCR analysis of 63 liver biopsy samples with various liver diseases revealed that IP-10 expression was significantly higher in AIH (p = 0.025) and chronic hepatitis C (p = 0.0043) than in other liver diseases. Interestingly, the amount of IP-10 mRNA expression was correlated with serum ALT values in AIH (p = 0.0006), but not in chronic hepatitis C (p = 0.43).

CONCLUSION

These results indicate the IP-10 expression in the liver might be used as a preferential marker of AIH, and that IP-10 has some pathophysiological roles in the liver damage of AIH.

The value of intraoperative cytology during transsphenoidal surgery for ACTH-secreting microadenoma

BACKGROUND

Microsurgical selective adenomectomy is the best established method available for the treatment of Cushing's disease. However, this surgical method warrants still more efforts to improve the results in minute microadenomas. In this paper the authors evaluate a method of intraoperative cytological investigations during transsphenoidal surgery.

METHOD

Between January 1997 and September 1999, transsphenoidal surgery was performed in 75 patients with the diagnosis of Cushing's disease. Fifty-one cases of proven microadenomas were reviewed.

FINDINGS

Of 51 cases, 33 tumors were 3 mm or less in diameter, here after called minute adenomas. In 49 of 51 (96.1%) microadenomas, adenoma tissue was identified by intraoperative cytological techniques. Postoperatively, only 35 of 51 ACTH-secreting microadenomas (68.6%) were confirmed by immunostaining methods. This lower percentage was most probably due to the small amount of tissue obtained. Therefore, in 14 cases (including 12 minute adenomas) the presence of the adenoma was only proven by cytological preparation and clinical outcome. The sensitivity of cytological preparations in cases of confirmed Cushing's disease was 100%.

INTERPRETATION

The method described here was particularly well suited for the intraoperative discrimination and documentation of minute adenomas. Cytological preparation appears to be effective in improving the adenoma finding rate and the surgical outcome in cases of Cushing's disease.

Sequences in the NS5A protein of hepatitis C virus and the serum alanine aminotransferase response to interferon therapy in Japanese patients

BACKGROUND AND AIMS

Chronic hepatitis C is a slowly progressive disease and eventually causes hepatocellular carcinoma in many patients. Although interferon (IFN) therapy has been used for viral eradication, its success rate is only about 30%. In patients in whom it has failed (non-responders), there are several patterns of serum alanine aminotransferase (ALT) values, and detection of serum HCV-RNA during and after IFN therapy and improved long term prognosis were reported in patients whose serum ALT values were normalised by IFN therapy even if HCV viraemia persisted. The present study sought to clarify the virological characteristics contributing to these differences.

METHODS

Complete or partial length dominant sequences of hepatitis C virus genotype 1b (HCV-1b) were determined by direct sequencing. Firstly, the complete sequences of HCV-1b genomes were determined in six non-responders; three showed normalisation of serum ALT values during IFN-alpha therapy and the other three did not. Subsequently, the amino acid residues that were different in the two groups were further analysed retrospectively in another 82 patients.

RESULTS

Comparison of the sequences suggested an association between amino acids 2154-2172 of HCV-1b and serum ALT normalisation. A retrospective analysis of 82 patients revealed that the number of amino acid substitutions in this region was the only statistically significant variable associated with ALT normalisation (odds ratio 31.0; 95% confidence interval 5.0-286) in multivariate analyses.

CONCLUSIONS

A HCV genomic region that correlates with the ALT response to IFN therapy appears to be present in virologically IFN ineffective patients.

Complete familial Currarino triad. Report of three cases in one family

The Currarino triad is a unique complex of congenital caudal anomalies including anorectal malformation, sacral bone abnormality, and presacral mass. In this report, the authors describe three cases with the complete Currarino triad in a family. The authors treated a 30-year-old mother with an anterior sacral meningocele, her 1-year-old son with a combination of anterior sacral meningocele and dermoid cyst, and her 4-year-old daughter with an epidermoid cyst. These three patients had associated sacral agenesis and anorectal malformations. To the authors' knowledge, this is the first report describing radiological and operative findings of complete familial Currarino triad in which a mother and her two children were affected.

Acute fatty liver of pregnancy showing microbial infection in the liver

A 24-year-old, nulliparous woman in her 30th week of pregnancy was admitted due to threatened premature delivery. Ritodrin chloride relieved the premature contraction of the uterus but jaundice and drowsiness appeared 7 weeks later. Laboratory data revealed disseminated intravascular coagulation (DIC) with intrahepatic cholestasis, and ultrasound examination showed fatty liver. The patient was diagnosed with acute fatty liver of pregnancy (AFLP). Emergency delivery by Caesarean section was performed at 37 weeks of pregnancy and the liver function and DIC improved immediately. Liver biopsy 13 days after delivery showed nuclear swelling and cytoplasmic ballooning with mild fatty deposition. These findings were relatively compatible with acute AFLP. Higher magnification and electron microscopy revealed intracytoplasmic bacteria and fungus in the residual stage. The bacterial infection could be considered related to AFLP.

Gliosarcoma associated with a huge cyst--case report

A 55-year-old female presented with a unique case of gliosarcoma with a huge cystic component manifesting as loss of consciousness, left-sided hemiparesis, and anisocoria. Computed tomography demonstrated a large cyst in the right frontal lobe, and enhancement of the mural nodule after administration of contrast medium. Emergent operation was performed. Xanthochromic fluid was aspirated, and the tumor was resected. The histological diagnosis was gliosarcoma based on the presence of gliomatous and sarcomatous components. She underwent a second operation because of tumor regrowth 3 weeks after the first operation. The postoperative course was satisfactory during radiation therapy with 60 Gy and chemotherapy. The diagnosis of gliosarcoma was difficult to make preoperatively because of the neuroradiological findings similar to low-grade gliomas. Gliosarcoma should be included in the differential diagnosis of huge cystic tumors.

Twenty-kilodalton human growth hormone (20K hGH) secretion from growth hormone-secreting pituitary adenoma cells in vitro

Circulating human growth hormone (GH) consists of several molecular isoforms. Increased proportion of circulating non-22K hGH and 20K hGH was reported in active acromegaly. In this study, we studied the release of 20K and 22K hGH from cultured GH-producing human pituitary adenoma cells in vitro. Pituitary adenoma cells obtained from 6 acromegalic patients were cultured and submitted to perifusion experiments. Concentrations of 20K and 22K hGH in the serum and the perifusion effluent were determined by specific enzyme-linked immunosorbent assays recently developed. The %20K value varied in a wide range from 3.58 to 8.72% in vitro and was lower than in the serum (mean+/-SD: 6.57+/-1.88% vs 9.08+/-2.12%, P<0.05). There was no correlation between the %20K values in vitro and in vivo (r=0.31, P>0.05). The in vitro secretions of 20K and 22K hGH were in parallel and strongly correlated (r=0.953, P<0.001). These findings suggest that different GH-producing pituitary adenoma cells secrete 20K hGH in variable amounts and that the proportion of 20K hGH in the serum might be affected by metabolic clearance of hGH isoforms. It was also suggested that 20K and 22K hGH might be secreted in toto from GH-producing human pituitary adenoma cells.

Surgical treatment of clinically nonsecreting pituitary adenomas in elderly patients

OBJECTIVE

The goal of this study was to evaluate the efficacy and safety of transsphenoidal pituitary surgery for elderly patients, using improved techniques of the past decade.

METHODS

We retrospectively analyzed 32 surgically treated cases of clinically nonsecreting pituitary adenomas in patients more than 70 years of age (mean, 73.9+/-3.4 yr). These patients were identified in a review of 982 patients with pituitary adenomas who were treated at University Hospital Eppendorf, Hamburg, between January 1991 and November 1999.

RESULTS

The mean preoperative duration of symptoms was 1.9 years (2 wk to 11 yr). The chiasmatic syndrome was present for 27 patients (84.4%). All patients underwent transsphenoidal surgery. Seven patients underwent reoperations. Preoperative assessments of anterior pituitary function revealed growth hormone deficiencies for 21 of 27 patients (77.8%), thyroid insufficiencies for 10 of 30 patients (33.3%), and adrenal insufficiencies for 13 of 29 patients (44.8%). Hypogonadism and hyperprolactinemia were observed for 76.7% and 46.9% of the patients, respectively. All tumors were macroadenomas, ranging from 18 to 50 mm (average, 33.6 mm) in size, including 7 enclosed and 25 invasive adenomas. Complete microscopic tumor resection was achieved in 24 cases, and subtotal removal was performed in 8 cases. There were no severe perioperative complications. In the cases involving hyperprolactinemia, serum prolactin levels were normalized for 8 of 11 patients (72.7%). Normal thyroid function was recovered for 1 of 10 patients (10.0%) with preoperative hypothyroidism. However, growth hormone or adrenal insufficiencies persisted for all patients with preoperative insufficiencies. Visual disturbances were improved for 19 of 23 patients (82.6%). All patients recovered well after surgery, with an average hospital stay of 16.3 days. Histological and immunohistochemical studies demonstrated gonadotroph adenomas in 56.7% of cases, null-cell adenomas in 26.7%, and oncocytomas in 13.3%.

CONCLUSION

Surgical treatment of nonsecreting pituitary adenomas causing visual disturbances is standard, even for elderly patients. In this series, transsphenoidal surgery was a safe procedure, with minimal morbidity and excellent tolerance. Age alone is not a contraindication for active treatment, particularly with transsphenoidal surgery.

Cloning of the cDNAs coding for two novel molybdo-flavoproteins showing high similarity with aldehyde oxidase and xanthine oxidoreductase

The cDNAs coding for two novel mouse molybdo-flavoproteins, AOH1 and AOH2 (aldehyde oxidase homolog 1 and 2), were isolated. The AOH1 and AOH2 cDNAs code for polypeptides of 1336 amino acids. The two proteins have similar primary structure and show striking amino acid identity with aldehyde oxidase and xanthine oxidoreductase, two other molybdo-flavoenzymes. AOH1 and AOH2 contain consensus sequences for a molybdopterin-binding site and two distinct 2Fe-2S redox centers. In its native conformation, AOH1 has a molecular weight consistent with a homotetrameric structure. Transfection of the AOH1 and AOH2 cDNAs results in the production of proteins with phenanthridine but not hypoxanthine oxidizing activity. Furthermore, the AOH1 protein has benzaldehyde oxidizing activity with electrophoretic characteristics identical to those of a previously identified aldehyde oxidase isoenzyme (Holmes, R. S. (1979) Biochem. Genet. 17, 517-528). The AOH1 transcript is expressed in the hepatocytes of the adult and fetal liver and in spermatogonia. In liver, the AOH1 protein is synthesized in a gender-specific fashion. The expression of AOH2 is limited to keratinized epithelia and the basal layer of the epidermis and hair folliculi. The selective cell and tissue distribution of AOH1 and AOH2 mRNAs is consistent with the localization of the respective protein products.

Involvement of LAT, Gads, and Grb2 in compartmentation of SLP-76 to the plasma membrane

B cell linker protein (BLNK) and Src homology 2 domain-containing leukocyte protein of 76 kD (SLP-76) are adaptor proteins required for B cell receptor (BCR) and T cell receptor function, respectively. Here, we show that expression of SLP-76 cannot reconstitute BCR function in Zap-70(+)BLNK(-) B cells. This could be attributable to inability of SLP-76 to be recruited into glycolipid-enriched microdomains (GEMs) after antigen receptor cross-linking. Supporting this idea, the BCR function was restored when a membrane-associated SLP-76 chimera was enforcedly localized to GEMs. Moreover, we demonstrate that addition of both linker for activation of T cells (LAT) and Grb2-related adaptor downstream of Shc (Gads) to SLP-76 allow SLP-76 to be recruited into GEMs, whereby the BCR function is reconstituted. The Gads function was able to be replaced by overexpression of Grb2. In contrast to SLP-76, BLNK did not require Grb2 families for its recruitment to GEMs. Hence, these data suggest a functional overlap between BLNK and SLP-76, while emphasizing the difference in requirement for additional adaptor molecules in their targeting to GEMs.

Genetic changes in the interferon sensitivity determining region of hepatitis C virus during the natural course of chronic hepatitis C

Amino acid mutations in the interferon sensitivity determining region (ISDR) are closely associated with the response to interferon in patients with hepatitis C virus genotype 1b (HCV-1b) infection. In this study, 36 patients chronically infected with HCV-1b, with no history of interferon therapy with respect to ISDR changes in HCV were studied. Two serum samples were obtained from each patient, with an average interval of 3.5 years, and predominant nucleotide and amino acid sequences of the ISDR at initial and subsequent time points were compared for each patient. Three of 12 patients with the wild type ISDR (no amino acid mutation in the ISDR compared to the consensus sequence) changed to the intermediate type (1 to 3 mutations) at later time points, whereas the other 9 still had the wild type. Similarly, 2 of 18 patients with the intermediate type changed to the wild type, whereas the other 16 patients continued to have the intermediate type. One of 6 patients with the mutant type (4 or more mutations) changed to the intermediate type, and the other 5 continued to have the mutant type. Although ISDR nucleotide changes/site/year were not significantly different among the 3 groups of patients, percentages of non-synonymous nucleotide changes were greater in the mutant type (63%) than the wild (9%) or the intermediate type (20%) (P < 0.05). These results show that mutations in the ISDR do not occur frequently, suggesting that interferon sensitivity does not change greatly during the natural course of the disease in each patient.

A comparative study of MIB-1 staining indices of gliomas measured by NIH Image analysis program and conventional manual cell counting method

To evaluate the NIH Image measured MIB-1 staining index (SI) as a useful tool for the determination of proliferative activity of gliomas, MIB-1 immunohistochemistry was performed on paraffin sections to estimate the proliferative activity of 50 gliomas. Five to eight RGB images at 200 magnifications were acquired per sample in a Macintosh computer using a RD-175 digital camera and Adope Photoshop program, followed by conversion of the RGB image to B (blue subtracted) and R (red subtracted) images and finally automatic cell counting of more than 1000 cells per sample by the NIH Image analysis program. The mean MIB-1 staining indices by both NIH count and visually assessed (manual) count respectively were 12.7% +/- 9.9% (mean +/- standard deviation) and 12.6% +/- 9.9% in all gliomas (n = 50), 2.9% +/- 0.6% and 2.3% +/- 0.6% in grade I and II astrocytomas (n = 9), 10.7% +/- 8.9% and 11.1% +/- 9.0% in grade III gliomas (n = 17), 16.1% +/- 9.1% and 16.3% +/- 9.1% in glioblastoma multiformes (n = 20), 26.0% +/- 4.9% and 24.5% +/- 2.6% in other glial tumors (n = 4). These paired values were assumed to be identical, since the p value obtained by paired t-test in all gliomas was 0.905. We conclude that the MIB-1 staining index measured by NIH Image is reliable and universal.

HLA-A33/B44/DR6 is highly related to intrahepatic cholestasis induced by tiopronin

In order to elucidate the immunogenetic predisposition of tiopronin (mercaptopropionylglycine)-induced intrahepatic cholestasis, human leukocyte antigen (HLA) was analyzed in patients with tiopronin-induced liver injury. HLA-A, -B, -C, and -DR loci of 14 patients (10 males and 4 females) with tiopronin-induced liver injury were compared with those of control subjects. The mean duration of tiopronin administration was 26 days and that of jaundice was 4.5 months. The elevation of biliary enzymes lasted from 2 months to up to 10 years. Most of the cases manifested intrahepatic cholestasis on liver biopsy. Lymphocyte transformation test with tiopronin was positive in 6 of 8 (75%) tested cases. Thirteen patients (92.9%) had HLA-A33, 10 (71.4%) had B44, and 9 (64.3%) patients had DR6. These are statistically higher in the patients with tiopronin-induced cholestasis than in the general population. Ten of those with tiopronin-induced liver dysfunction (71.4%) had A33/B44 and 8 (57.1%) had A33/B44/DR6 in their haplotype. In conclusion, long-lasting tiopronin-induced intrahepatic-cholestasis is highly linked to specific HLA-A33, -B44 and -DR6.

Characteristics of hepatitis C viral genome associated with disease progression

The clinical presentations of chronic hepatitis C are not uniform. Some patients show persistently high serum alanine transaminase (ALT) values and develop liver cirrhosis and hepatocellular carcinoma (HCC), whereas serum ALT values stay normal in other patients. The mechanism causing this diversity remains to be elucidated. The aim of this study was to identify genomic characteristics of hepatitis C virus (HCV) genotype 1b associated with disease progression. Full length sequences of HCV were determined in 14 patients who showed persistently normal serum ALT values (normal ALT group) and 13 cirrhotics with HCC (HCC group). Residues in which amino acid usage was different between these 2 groups were extracted, and Progression score was defined as the total number of residues with 7 amino acids, more frequently present in the HCC group than in the normal ALT group. In the validation of this Progression score in 9 patients with normal ALT and 25 with HCC, the score was significantly higher in the HCC group (3.1 +/- 1.1 vs. 2.0 +/- 0.9, P =.019). Finally, the correlation between the score and clinical markers related to disease progression was analyzed. In a total of 107 patients with chronic HCV infection, the Progression score was correlated significantly with platelet counts (r = -0.31, P =.0024) by multivariate analysis. In conclusion, high Progression scores were associated with the presence of HCC and low platelet counts. Sequences of the HCV-1b genome may be related to the progression of chronic hepatitis C.

The mouse aldehyde oxidase gene: molecular cloning, chromosomal mapping and functional characterization of the 5'-flanking region

In this article, we report on the chromosome mapping and molecular cloning of the genetic locus encoding the mouse molybdo-iron/sulfur-flavoprotein aldehyde oxidase. The aldehyde oxidase locus maps to mouse chromosome 1 band C1-C2, as determined by fluorescence in situ hybridization experiments conducted on metaphase chromosomes. The gene is approximately 83 kb long and consists of 35 exons. The exon/intron boundaries are perfectly conserved relative to the corresponding human homolog and almost completely conserved relative to the mouse xanthine oxidoreductase gene. This further supports the concept that the aldehyde oxidase and xanthine oxidoreductase loci evolved from the same ancestral precursor by a gene duplication event. The position of a major transcription start site was defined by primer extension and RNase mapping analysis. The 5'-flanking region of the mouse aldehyde oxidase gene contains a functional and orientation-dependent promoter as well as several putative binding sites for known cell-specific and general transcription factors. Deletion analysis of the 5'-flanking region defines an approximately 470 bp DNA stretch which is necessary and sufficient for the transcription of the mouse aldehyde oxidase gene.

Prevalence and significance of naturally occurring mutations in the surface and polymerase genes of hepatitis B virus

The prevalence and clinical significance of naturally occurring mutations in the full-length surface and overlapping polymerase genes of hepatitis B virus (HBV) were analyzed in 42 patients with chronic hepatitis. Mutations were observed in 10 patients (24%) in the a determinant region, which is the neutralizing epitope within the major hydrophilic region of the surface gene. A high proportion of these mutations (17/18; 94%) occurred in the first loop, unlike mutations induced by immunization. The presence of serum antibody to hepatitis B surface antigen was significantly associated with these mutations. No other region of the surface gene contained any cluster of mutations. These results suggest that escape mutations commonly contribute to persistency in the natural course of HBV infection. In contrast, mutations affecting the major catalytic domains of the polymerase gene, which could alter susceptibility to antiviral nucleoside analogues, were not detected at all.

Time-related changes in full-length hepatitis C virus sequences and hepatitis activity

The activity of hepatitis varies in chronic hepatitis C virus (HCV) infection. Some patients show persistently normal serum alanine aminotransferase (ALT) values, whereas the others show high-ALT values and progress to liver cirrhosis or hepatocellular carcinoma. However, virological mechanisms causing hepatitis have not fully been elucidated. We analyzed serial changes in full-length HCV sequences in 10 patients with various profiles of hepatitis activity. In the nonstructural 5A (NS5A) and NS5B, the rate of amino acid changes, as well as the proportion of nonsilent ones, was low in patients with normal ALT values compared with those with abnormal ALT (for the rate of amino acid changes, 0 x 10(-3) vs 3.19 x 10(-3) changes/site/year (P = 0.037) in NS5A and 0 x 10(-3) vs 1.22 x 10(-3) changes/site/year (P = 0.023) for NS5B, for the proportion of nonsilent changes, 4 vs 22% (P = 0.017) in NS5A and 0 vs 16% (P = 0. 039) in NS5B). Also, the flare-up of hepatitis coincided with higher nucleotide/amino acid substitution rates in NS5B. In conclusion, the genomic structures of the NS5A and NS5B regions may correlate with hepatitis activity in chronic hepatitis C.

Differential effect of interferon on hepatitis C virus 1b quasispecies in the nonstructural protein 5A gene

A close correlation was reported between amino acid mutations in the nonstructural protein 5A (interferon [IFN] sensitivity-determining region [ISDR]) of hepatitis C virus (HCV)-1b and the response to IFN therapy. The dynamic change of ISDR quasispecies during IFN treatment was investigated in 22 patients. In 18 nonresponders, the number of ISDR mutations in major quasispecies decreased after therapy (P=.039). In each nonresponder, the percentage of wild-type (no mutations in the ISDR) quasispecies increased after treatment (P=.008), whereas the percentages of intermediate- (1-3 mutations) and mutant-type (>/=4 mutations) quasispecies decreased (P=.037 and P=.043, respectively). No mutant-type quasispecies were detected after therapy. Four complete responders had only quasispecies with >/=3 mutations before therapy. Thus, HCVs have fewer mutations in the ISDR after IFN therapy than those before therapy. These IFN-resistant HCVs were already present before therapy as minor quasispecies and were selected by IFN in nonresponders.

Mutations in nonstructural protein 5A gene and response to interferon in hepatitis C virus genotype 2 infection

An association has been reported between mutations in the amino acid residues 2209-2248 of the nonstructural protein 5A (NS5A) gene (interferon-sensitivity determining region [ISDR]) and interferon efficacy in hepatitis C virus (HCV)-1b infection. This relationship was analyzed in chronic HCV-2 infection. Forty patients with HCV-2a and 35 with HCV-2b were treated with interferon alfa for 6 months with a total dose of 468 to 860 million units. Pretreatment NS5A sequences were determined by direct sequencing. A higher complete and sustained response rate was observed in HCV-2a than in HCV-2b (70% vs. 34%; P =.003). Serum HCV-RNA levels were lower in complete responders than nonresponders in HCV-2a (P =.049) and HCV-2b (P =. 02). The number of amino acid mutations was greater in complete responders than nonresponders in NS5A2193-2228 (the region corresponding to the ISDR of HCV-1b) alone (P =.049), or NS5A2163-2228 consisting of NS5A2193-2228 plus its upstream region (P =.02) in HCV-2a, but not in HCV-2b. A significant inverse correlation was observed between serum HCV-RNA levels and the number of amino acid mutations in NS5A2193-2228 (P =.003) or NS5A2163-2228 (P =.005) in HCV-2a. With multivariate analysis, the number of substitutions in NS5A was an independent predictor for complete response in HCV-2a (odds ratio: 6.4; P =.03). Interferon efficacy is associated with amino acid variations in the NS5A protein in HCV-2a infection.

Cutting edge: association of phospholipase C-gamma 2 Src homology 2 domains with BLNK is critical for B cell antigen receptor signaling

To explore the mechanism(s) by which phospholipase C (PLC)-gamma 2 participates in B cell Ag receptor (BCR) signaling, we have studied the function of PLC-gamma 2 mutants in B cells deficient in PLC-gamma 2. Mutation of the N-terminal Src homology 2 domain [SH2(N)] resulted in the complete loss of inositol 1,4, 5-trisphosphate generation upon BCR engagement. A possible explanation for the SH2(N) requirement was provided by findings that this mutation abrogates the association of PLC-gamma 2 with an adaptor protein BLNK. Moreover, expression of a membrane-associated form (CD16/PLC-gamma 2) with SH2(N) mutation required coligation of BCR and CD16 for inositol 1,4,5-trisphosphate generation. Together, our results suggest a central role for the SH2(N) domain in directing PLC-gamma 2 into the close proximity of BCR signaling complex by its association with BLNK, whereby PLC-gamma 2 becomes tyrosine phosphorylated and thereby activated.

Shc regulates epidermal growth factor-induced activation of the JNK signaling pathway

Two adaptor molecules, Grb2 and Shc, have been implicated in the extracellular signal-regulated kinase (ERK) activation by receptor tyrosine kinases such as the epidermal growth factor receptor (EGFR). Here we show that the EGF-mediated ERK activation is abolished by loss of Grb2, whereas this response is not affected by loss of Shc. Conversely, the EGF-mediated c-Jun N-terminal kinase (JNK) activation is dependent on Shc, but not Grb2. These findings strongly support distinct roles for Grb2 and Shc in controlling ERK and JNK activation after EGF stimulation.

Molecular cloning of the cDNA coding for mouse aldehyde oxidase: tissue distribution and regulation in vivo by testosterone

The cDNA coding for mouse aldehyde oxidase (AO), a molybdoflavoprotein, has been isolated and characterized. The cDNA is 4347 nt long and consists of an open reading frame predicting a polypeptide of 1333 amino acid residues, with 5' and 3' untranslated regions of 13 and 335 nt respectively. The apparent molecular mass of the translation product in vitro derived from the corresponding cRNA is consistent with that of the monomeric subunit of the AO holoenzyme. The cDNA codes for a catalytically active form of AO, as demonstrated by transient transfection experiments conducted in the HC11 mouse mammary epithelial cell line. The deduced primary structure of the AO protein contains consensus sequences for two distinct 2Fe-2S redox centres and a molybdopterin-binding site. The amino acid sequence of the mouse AO has a high degree of similarity with the human and bovine counterparts, and a significant degree of relatedness to AO proteins of plant origin. Northern blot and in situ hybridization analyses demonstrate that hepatocytes, cardiocytes, lung endothelial or epithelial cells and oesophagus epithelial cells express high levels of AO mRNA. In the various tissues and organs considered, the level of AO mRNA expression is not strictly correlated with the amount of the corresponding protein, suggesting that the synthesis of the AO enzyme is under translational or post-translational control. In addition, we observed sex-related regulation of AO protein synthesis. In the liver of male animals, despite similar amounts of AO mRNA, the levels of the AO enzyme and corresponding polypeptide are significantly higher than those in female animals. Treatment of female mice with testosterone increases the amounts of AO mRNA and of the relative translation product to levels similar to those in male animals.

Bruton's tyrosine kinase activity is negatively regulated by Sab, the Btk-SH3 domain-binding protein

Bruton's tyrosine kinase (Btk) is a cytoplasmic tyrosine kinase that is crucial for human and murine B cell development, and its deficiency causes human X-linked agammaglobulinemia and murine X-linked immunodeficiency. In this report, we describe the function of the Btk-binding protein Sab (SH3-domain binding protein that preferentially associates with Btk), which we reported previously as a newly identified Src homology 3 domain-binding protein. Sab was shown to inhibit the auto- and transphosphorylation activity of Btk, which prompted us to propose that Sab functions as a transregulator of Btk. Forced overexpression of Sab in B cells led to the reduction of B cell antigen receptor-induced tyrosine phosphorylation of Btk and significantly reduced both early and late B cell antigen receptor-mediated events, including calcium mobilization, inositol 1, 4,5-trisphosphate production, and apoptotic cell death, where the involvement of Btk activity has been demonstrated previously. Together, these results indicate the negative regulatory role of Sab in the B cell cytoplasmic tyrosine kinase pathway.

BLNK required for coupling Syk to PLC gamma 2 and Rac1-JNK in B cells

Signaling through the B cell receptor (BCR) is essential for B cell function and development. Despite the key role of Syk in BCR signaling, little is known about the mechanism by which Syk transmits downstream effectors. BLNK (B cell LiNKer protein), a substrate for Syk, is now shown to be essential in activating phospholipase C (PLC)gamma 2 and JNK. The BCR-induced PLC gamma 2 activation, but not the JNK activation, was restored by introduction of PLC gamma 2 membrane-associated form into BLNK-deficient B cells. As JNK activation requires both Rac1 and PLC gamma 2, our results suggest that BLNK regulates the Rac1-JNK pathway, in addition to modulating PLC gamma 2 localization.