A single site study to investigate the current prevalence of anti-hepatitis C virus antibody among substance use disorder patients in Hiroshima-Insufficient testing and diagnosis.

AIMS: Hepatitis C virus (HCV) infection among drug users presents an important public health problem; however, little recognition and few approaches to address this issue in Japan. This study was conducted to investigate the current disease status by assessing anti-HCV antibody (Ab) seroprevalence among people who inject drugs (PWIDs) and people who use drugs (PWUDs) in Hiroshima, Japan. METHODS: This study was a psychiatric single-site chart review in patients with drug abuse problems in the Hiroshima region. The primary outcome was anti-HCV Ab prevalence among PWIDs who underwent anti-HCV Ab testing. The secondary outcomes included the prevalence of anti-HCV Ab among PWUDs who underwent anti-HCV Ab testing and the proportion of patients who underwent anti-HCV Ab examination. RESULTS: A total of 222 PWUD patients were enrolled. Among these, 16 patients (7.2%) had records of injection drug use (PWIDs). Eleven (68.8%) of the 16 PWIDs received anti-HCV Ab tests, and 4 (36.4%, 4/11) were anti-HCV Ab-positive. Among 222 PWUDs, 126 (56.8%) patients received anti-HCV Ab tests, and 57 of these patients (45.2%, 57/126) were anti-HCV Ab-positive. CONCLUSION: The prevalence of anti-HCV Ab among PWIDs and PWUDs who visited the study site was higher than the general population, which was 2.2% among hospitalized patients between May 2018 and November 2019. Considering the World Health Organization's (WHO) elimination goal and recent advances in HCV treatment, patients with drug abuse experience should be encouraged to take HCV tests and consult hepatologists for further investigations and treatment if they are positive for anti-HCV Ab.

Long-term safety and effectiveness of adalimumab for the treatment of Japanese patients with rheumatoid arthritis: 3-year results from a postmarketing surveillance of 552 patients.

OBJECTIVES: To determine the safety and effectiveness of and identify associated factors in long-term adalimumab (ADA) treatment of Japanese patients with rheumatoid arthritis (RA). METHODS: Of 7740 patients participating in the all-case postmarketing surveillance study, 552 were enrolled in the present study and observed for 3 years. The safety and effectiveness of ADA were analyzed in 509 and 430 patients, respectively. RESULTS: Adverse drug reactions (ADRs) were reported in 34.2% of patients (23.3/100 person-years [PYs]); serious ADRs (SADRs) were reported in 10.6% (5.9/100 PYs). The most common ADRs and SADRs were infection (16.5%) and serious infection (6.1%), respectively. Seven patients (1.4%) developed malignancies. Multivariate analysis revealed that the risk factors for SADRs were age ≥65 years and respiratory disorder at baseline. The proportion of patients who achieved remission (28-joint count Disease Activity Score based on four erythrocyte sedimentation rates <2.6) increased from 3.3% at baseline to 49.2% at 36 months. Significant predictors of failure to achieve remission were female sex, age ≥65 years, blood disorders and advanced structural change at baseline. CONCLUSIONS: Overall, no unknown safety issues were noted during the 3-year treatment with ADA in Japanese patients with RA.

Low disease activity for up to 3 years after adalimumab discontinuation in patients with early rheumatoid arthritis: 2-year results of the HOPEFUL-3 Study.

BACKGROUND: This study was conducted to evaluate the feasibility of long-term adalimumab (ADA) discontinuation after achievement of low disease activity (LDA) in Japanese patients with early rheumatoid arthritis (RA) and to identify predictors of LDA maintenance. METHODS: In the HOPEFUL-1 study, patients received initial therapy with either ADA plus methotrexate (MTX; intensive therapy) or MTX alone (standard therapy) for 26 weeks, followed by ADA + MTX for 26 weeks. In the HOPEFUL-2 study, patients received ADA + MTX (ADA continuation) or MTX alone (ADA discontinuation) for 52 weeks. HOPEFUL-3 was an observational study that enrolled patients who had completed HOPEFUL-2; these patients were followed for an additional 104 weeks. RESULTS: Of the 172 patients enrolled in the HOPEFUL-3 study, 135 (ADA continuation, n = 61; ADA discontinuation, n = 74) with 28-joint Disease Activity Score using C-reactive protein (DAS28-CRP) values at both week 52 (start of HOPEFUL-2) and week 208 (end of HOPEFUL-3) were included in the effectiveness analysis. At week 208, 58 (95.1%) of 61 patients and 59 (79.7%) of 74 patients who continued or discontinued ADA, respectively, had LDA (DAS28-CRP <3.2). Initial intensive therapy was associated with a better outcome than standard therapy in terms of change in modified total Sharp score from week 0 to week 208, which was ≤0.5 (64% vs. 30%). The incidence of adverse events was significantly lower in the ADA discontinuation group than in the ADA continuation group (9.7% vs. 32.9%; p < 0.001). CONCLUSIONS: Approximately 80% of patients who discontinued ADA for 3 years after achieving LDA with ADA + MTX were still in LDA, with a lower incidence of adverse events than patients who continued ADA. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01346501. Registered 29 April 2011.

Adalimumab discontinuation in patients with early rheumatoid arthritis who were initially treated with methotrexate alone or in combination with adalimumab: 1†year outcomes of the HOPEFUL-2 study.

OBJECTIVES: To evaluate the impact of discontinuation of adalimumab (ADA) for 1 year in Japanese patients with early rheumatoid arthritis (RA). METHODS: This 52-week postmarketing study, HOPEFUL-2, enrolled patients who had completed HOPEFUL-1 for early RA, in which patients received either ADA + methotrexate (MTX) or MTX alone in a 26-week randomised phase, followed by ADA+MTX in a 26-week open-label phase. RESULTS: A total of 220 patients (ADA discontinuation: 114 patients vs ADA continuation: 106 patients) were enrolled in this study. The proportion of patients with sustained low disease activity (LDA) in the ADA discontinuation group was significantly lower than that in the continuation group (80% (64/80 patients) vs 97% (71/73 patients); p=0.001); however, most patients sustained LDA in both groups. In patients with 28-joint disease activity score (DAS28)-C reactive protein ≤2.0 at week 52, the proportion of patients who achieved sustained LDA at week 104 was 93%, suggesting that DAS28 remission may be a predictor to indicate biological-free disease control in patients with early RA. The incidence of adverse events (AE) was significantly lower in the ADA discontinuation group than in the continuation group (34.2% (39/114 patients) vs 48.1% (51/106 patients); p=0.04), most notably for infection (14.9% vs 27.4%, p=0.031). CONCLUSIONS: Although ADA discontinuation was associated with an increase in disease activity, a large proportion of patients maintained LDA with MTX monotherapy after ADA discontinuation. Since ADA discontinuation was associated with a lower AE incidence, physicians should weigh the risks and benefits of ADA discontinuation. TRIAL REGISTRATION NUMBER: NCT01163292.

Safety and effectiveness of adalimumab in Japanese rheumatoid arthritis patients: postmarketing surveillance report of 7740 patients.

OBJECTIVES: To confirm the safety and effectiveness of adalimumab and to evaluate the influence of the concomitant use of methotrexate (MTX). METHODS: Postmarketing surveillance of 7740 Japanese rheumatoid arthritis (RA) patients was performed. All patients who received adalimumab in the registration period were followed for 28 weeks after starting treatment for safety and 24 weeks for effectiveness. Effectiveness was measured by duration of morning stiffness, swollen and tender joint counts (28 joints), patient global assessment of disease activity, erythrocyte sedimentation rate and serum C-reactive protein. RESULTS: Comparable rates of adverse drug reactions (ADRs) were reported in this study and in the interim analysis. Age, pulmonary disease history or comorbidity, co-existing diabetes mellitus, concomitant MTX at doses of > 8 mg/week and concomitant glucocorticoids at doses of > 5 mg/day were risk factors for infections. All mean values of effectiveness measurements improved. Relatively lower disease activity at baseline, biologic-naïve, concomitant MTX use and early RA stage/low functional class were background factors contributing to the effectiveness. The combination of adalimumab with MTX improved the response to adalimumab treatment. CONCLUSION: Adalimumab, especially with concomitant use of MTX, provided significant improvement in disease activity, without any unexpected ADRs in Japanese RA patients.

Suppression of beta-catenin signaling by liver X receptor ligands.

The nuclear receptors liver X receptor (LXR) alpha and LXRbeta serve as oxysterol receptors and play an important role in the regulation of lipid metabolism. We investigated the potential effects of LXRs on pathways of colon carcinogenesis and found that LXR activation suppresses the transactivation activity of beta-catenin, a key molecule in Wnt signaling. LXRalpha and LXRbeta inhibited beta-catenin transactivation of T cell factor-mediated transcription in a ligand-dependent manner. LXR activation suppressed an oncogenic beta-catenin, which has phosphorylation site mutations, and did not change beta-catenin protein expression in cells. In contrast, beta-catenin enhanced LXR transactivation activity. Nuclear LXRs and beta-catenin were coimmunoprecipitated in colon cancer HCT116 cells, and in vitro experiments showed that LXRs bind directly to the Armadillo repeat region of beta-catenin in a ligand-independent manner. LXR ligand decreased mRNA expression of beta-catenin targets, MYC, MMP7 and BMP4, and recruited LXRs to MYC and MMP7 promoters. Transfection of a dominant negative LXR to HCT116 cells and experiments using LXR-null cells showed the involvement of cellular LXRs in beta-catenin suppression and proliferation inhibition. The results show lipid-sensing receptor LXRs regulate the beta-catenin activity and cellular proliferation.

Participation of nuclear localization signal 2 in the 3'-ETS domain of FLI1 in nuclear translocation of various chimeric EWS-FLI1 oncoproteins in Ewing tumor.

A t(11;22)(q24;q12) translocation is present in 90% of Ewing's sarcoma, and results in the formation of the EWS-FLI1 fusion gene encoding an oncogenic transcription factor. To clarify the function of chimeric EWS-FLI1 proteins, an identification of a nuclear localization signal (NLS) in the EWS, FLI1 and EWS-FLI1 proteins is important because the chimeric oncoprotein may lose or gain NLS function different from native proteins resulting in different subcellular localization, and in deregulated gene expression. Furthermore, some studies reported that patients with one type of fusion gene ('type 1') had better overall survival than those with other types, suggesting that functional differences may be present among various fusion proteins. There has been only one study reporting a NLS in EWS, but none reporting those in FLI1 and EWS-FLI1. To clarify the molecular mechanisms of Ewing tumor development, we first identified the NLSs of EWS and FLI1. We allocated the NLS to amino acid residues 632-656 near the C-terminal region of EWS that is different from the previous study, and identified two NLSs of FLI1, NLS1 (63-90) in the N-terminal domain and NLS2 (319-360) in the 3'-ETS domain. In addition, the present study showed that all of the EWS-FLI1 fusion proteins completely reside in the nucleus without affecting the frequency of nuclear localization among variants, suggesting that NLS2 of FLI1 was used for nuclear translocation of various EWS-FLI1 fusion proteins.

Selective allosteric ligand activation of the retinoid X receptor heterodimers of NGFI-B and Nurr1.

NGFI-B, an orphan member of the NR4A subfamily of the nuclear receptors, recognizes specific sequences in the promoters of neuronal target genes as a monomer. Although NGFI-B also forms a heterodimer with the retinoid X receptor (RXR), a receptor for 9-cis retinoic acid (9CRA), endogenous targets of the heterodimer have not been identified. We investigated the role of RXR ligand binding in NGFI-B/RXR activation and found that dibenzodiazepine-derived ligands, such as the weak RXR agonist HX600, selectively activate NGFI-B/RXR heterodimers. HX600 also activated the heterodimer formed by RXR and Nurr1, another NR4A subfamily receptor. In an assembly assay that detects ligand-dependent reconstruction of the ligand-binding domain, HX600 and not 9CRA induced an allosteric ligand effect on NGFI-B through RXRalpha binding. The data indicate that the RXR heterodimers of NGFI-B and Nurr1 are selectively activated by the RXR ligand HX600, and that compounds such as HX600 will be valuable tools in investigating NGFI-B and Nurr1 function.

Enhancement of ligand-dependent vitamin D receptor transactivation by the cardiotonic steroid bufalin.

Bufalin, a bufadienolide type cardiotonic steroid that is one of the major components of the toad venom-prepared traditional Chinese medicine called Ch'an Su or Senso, exhibits a cardiotonic action by inhibiting the membranous Na(+),K(+)-ATPase. Bufalin also induces differentiation of leukemia cells alone or in combination with other differentiation inducers including 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)]. In this study, we performed a transient cotransfection assay using a vitamin D receptor (VDR) expression vector and a luciferase reporter and found that although bufalin did not transactivate the VDR, it effectively enhanced VDR activity induced by 1,25(OH)(2)D(3). Bufalin also augmented VDR activation by bile acid ligands, such as lithocholic acid and 3-ketocholanic acid. Other cardiotonic steroids including ouabain, digitoxigenin and cinobufagin did not enhance VDR activation. Bufalin did not bind directly to VDR but did modulate the interaction of VDR and cofactors, such as steroid receptor coactivator-1 and nuclear receptor corepressor. Bufalin treatment significantly increased the expression of an endogenous VDR target gene, CYP24, in kidney- and monocyte-derived cell lines treated with 1,25(OH)(2)D(3). The data indicate that bufalin-mediated cellular mechanisms such as interaction with Na(+), K(+)-ATPase may affect VDR transcriptional activity. Bufalin may be a useful tool in the investigation of VDR regulation by membrane-originating cellular signals and of pathophysiological mechanisms linking VDR to cardiovascular dysfunction.

Selective activation of vitamin D receptor by lithocholic acid acetate, a bile acid derivative.

The vitamin D receptor (VDR), a member of the nuclear receptor superfamily, mediates the biological actions of the active form of vitamin D, 1alpha,25-dihydroxyvitamin D(3). It regulates calcium homeostasis, immunity, cellular differentiation, and other physiological processes. Recently, VDR was found to respond to bile acids as well as other nuclear receptors, farnesoid X receptor (FXR) and pregnane X receptor (PXR). The toxic bile acid lithocholic acid (LCA) induces its metabolism through VDR interaction. To elucidate the structure-function relationship between VDR and bile acids, we examined the effect of several LCA derivatives on VDR activation and identified compounds with more potent activity than LCA. LCA acetate is the most potent of these VDR agonists. It binds directly to VDR and activates the receptor with 30 times the potency of LCA and has no or minimal activity on FXR and PXR. LCA acetate effectively induced the expression of VDR target genes in intestinal cells. Unlike LCA, LCA acetate inhibited the proliferation of human monoblastic leukemia cells and induced their monocytic differentiation. We propose a docking model for LCA acetate binding to VDR. The development of VDR agonists derived from bile acids should be useful to elucidate ligand-selective VDR functions.

Molecular mechanism of nuclear translocation of an orphan nuclear receptor, SXR.

The steroid and xenobiotic receptor (SXR) is an orphan nuclear receptor that plays a key role in the regulation of xenobiotic response by controlling the expression of drug metabolizing and clearance enzymes. We observed that pregnane X receptor (PXR), the mouse ortholog of SXR, was retained in the cytoplasm of hepatic cells of untreated mice, whereas PXR was translocated to the nucleus after administration of a ligand, pregnenolone 16 alpha-carbonitrile. To understand the molecular mechanisms underlying the xenochemical-dependent nuclear translocation of SXR, we identified the signal sequence of SXR that regulates its nuclear translocation; using an in vitro expression system, we allocated the nuclear localization signal (NLS) to amino acid residues 66 to 92 within the DNA binding domain of SXR. The NLS of SXR is characterized as the bipartite type, and is recognized by the three molecular species of importin alpha: Rch1 (PTAC58), NPI1, and Qip1, in the presence of PTAC97 of importin beta to target the nuclear pore. The nuclear translocation of SXR was observed as an essential regulatory event for transcription of its target genes such as CYP3A4. These results strongly suggest that the molecular mechanism of the nuclear import of SXR was different from that of another xenosensor, the constitutively active receptor, whose translocation into the nucleus is mediated by a leucine-rich xenochemical response signal in its ligand binding domain.