Predictive model of bosentan-induced liver toxicity in Japanese patients with pulmonary arterial hypertension.

Bosentan, an endothelin receptor antagonist, has been widely used as a first-line medication for the treatment of pulmonary arterial hypertension (PAH). It has been shown to improve symptoms of hypertension, exercise capacity, and hemodynamics and prolong time to clinical worsening. However, liver dysfunction is a major side effect of bosentan treatment that could hamper the optimal management of patients with PAH. Previously, we demonstrated, using drug metabolism enzymes and transporters analysis, that the carbohydrate sulfotransferase 3 (CHST3) and CHST13 alleles are significantly more frequent in patients with elevated aminotransferases during therapy with bosentan than they are in patients without liver toxicity. In addition, we constructed a pharmacogenomics model to predict bosentan-induced liver injury in patients with PAH using two single-nucleotide polymorphisms and two nongenetic factors. The purpose of the present study was to externally validate the predictive model of bosentan-induced liver toxicity in Japanese patients. We evaluated five cases of patients treated with bosentan, and one presented with liver dysfunction. We applied mutation alleles of CHST3 and CHST13, serum creatinine, and age to our model to predict liver dysfunction. The sensitivity and specificity were calculated as 100% and 50%, respectively. Considering that PAH is a rare disease, multicenter collaboration would be necessary to validate our model.

Genetic and clinical prediction models for the efficacy and hepatotoxicity of methotrexate in patients with rheumatoid arthritis: a multicenter cohort study.

The objective of the study is to develop genetic and clinical prediction models for the efficacy and hepatotoxicity of methotrexate (MTX) in patients with rheumatoid arthritis (RA). Among RA patients treated with MTX, 1966 polymorphisms of 246 enzymes/transporters relevant to pharmacokinetics and pharmacodynamics were measured by the Drug Metabolism Enzymes and Transporters (DMET) microarray and direct sequencing, and clinical variables at baseline were collected. For efficacy, response criteria of the European League Against Rheumatism were used to classify patients as responders or non-responders. Hepatotoxicity was defined as elevations of aspartate aminotransferase or alanine aminotransferase ≥1.5 times the reference range upper limit. Among 166 patients, a genetic prediction model for efficacy using seven polymorphisms showed the area under the receiver operating characteristic curve (AUC) was 0.822, with 74.3% sensitivity and 76.8% specificity. A combined genetic and clinical model indicated the AUC was 0.844, with 81.5% sensitivity and 76.9% specificity. By incorporating clinical variables into the genetic model, the overall category-free net reclassification improvement (NRI) was 0.663 (P < 0.0001) and the overall integrated discrimination improvement (IDI) was 0.083 (P = 0.0009). For hepatotoxicity, a genetic prediction model using seven polymorphisms showed the AUC was 0.783 with 70.0% sensitivity and 80.0% specificity, while the combined model indicated the AUC was 0.906 with 85.1% sensitivity and 87.8% specificity (overall category-free NRI: 1.002, P < 0.0001; overall IDI: 0.254, P < 0.0001). Our genetic and clinical models demonstrated moderate diagnostic accuracy for MTX efficacy and high accuracy for hepatotoxicity. These findings should, however, be validated and interpreted with a caution until external validation.

[Situation and Problems of Activities for Cancer Cooperative Treatment in Kumamoto].

The Consultation Support and Information Providing Committee, which is a subsidiary organization of the Kumamoto Cancer Medical Cooperation Council, created a critical path called"my medical chart,"which is used in Kumamoto prefecture jointly. The path was implemented in 2009 at designated cancer hospitals. For promoting cancer consultation support centers and nurturing cancer counselors, the Cancer Special Counselor Working Group was formed, and activities were initiated. These activities of the Committee resulted in an increased number of patients visiting the designated cancer hospitals. The number of medical cooperations using"my medical chart"exceeded 4,800. A disparity was also observed in cancer treatment, such as surgery, radiotherapy, and chemotherapy. We investigate the situation of cancer treatment and report current problems and future issues.

Redox-tuning of oxidizing disulfide oxidoreductase generates a potent disulfide isomerase.

Oxidative folding of extracellular proteins is pivotal for the biogenesis of bacterial virulence factors. Escherichia coli DsbA catalyzes disulfide bond formation in extracellular proteins and in multicomponent architectures on the cell surface. The present study assessed the significance of the redox properties of DsbA by exploiting the plaque-forming ability of bacteriophage M13, which specifically recognizes F-pili during infection of the host cell. A library of mutant dsbA genes was constructed by randomizing the dipeptide XX sequence in the active-site redox motif CXXC and then screened for mutants that altered plaque yield and appearance. In total, 24 dsbA mutant alleles produced substantially different degrees of complementation, and one mutant dsbA gene that encodes a CDIC sequence produced over 40-fold more clear plaques than wild type dsbA. The redox potential of purified DsbA [CDIC] was -172 mV, representing a less-oxidizing catalysis than the wild type DsbA (-122 mV), but one that is closer to yeast protein disulfide isomerase (-175 mV). DsbA [CDIC] exhibited a greater ability to refold fully denatured glutathionylated ribonuclease A than the wild type enzyme and a DsbA [CRIC] mutant, which has the same redox potential of -172 mV. Homology modeling and molecular dynamics simulation suggest that the CDIC mutant may have an enlarged substrate-binding cleft near the redox center, which confers kinetic advantages when acting on protein substrates.

CHST3 and CHST13 polymorphisms as predictors of bosentan-induced liver toxicity in Japanese patients with pulmonary arterial hypertension.

Bosentan, an endothelin receptor antagonist, has been widely used as a first-line drug for the treatment of pulmonary arterial hypertension (PAH). In addition, bosentan is approved for patients with digital ulcers related to systemic sclerosis. Liver dysfunction is a major adverse effect of bosentan and may lead to discontinuation of therapy. The purpose of this study was to identify genomic biomarkers to predict bosentan-induced liver injury. A total of 69 PAH patients were recruited into the study. An exploratory analysis of 1936 single-nucleotide polymorphisms (SNPs) in 231 genes involved in absorption, distribution, metabolism, and elimination of multiple medications using Affimetrix DMET™ (Drug Metabolism Enzymes and Transporters) chips was performed. We extracted 16 SNPs (P < 0.05) using the Jonckheere-Terpstra trend test and multiplex logistic analysis; we identified two SNPs in two genes, CHST3 and CHST13, which are responsible for proteoglycan sulfation and were significantly associated with bosentan-induced liver injury. We constructed a predictive model for bosentan-induced liver injury (area under the curve [AUC]: 0.89, sensitivity: 82.61%, specificity: 86.05%) via receiver operating curve (ROC) analysis using 2 SNPs and 2 non-genetic factors. Two SNPs were identified as potential predictive markers for bosentan-induced liver injury in Japanese patients with pulmonary arterial hypertension. This is the first pharmacogenomics study linking proteoglycan sulfating genes to drug-induced liver dysfunction, a frequently observed clinical adverse effect of bosentan therapy. These results may provide a way to personalize PAH medicine as well as provide novel mechanistic insights to drug-induced liver dysfunction.

[MMP-3 as a Biomarker of Disease Activity of Rheumatoid Arthritis].

The aim of this study was to confirm the clinical significance of serum MMP-3 measurement in the evalua- tion of disease activity and effectiveness of treatment in patients with rheumatoid arthritis (RA). MMP-3 was measured for 206 outpatients with RA during a period of 4 months, and also serially measured for RA patients treated with methotrexate(MTX) alone or together with infliximab (IFX). Serum MMP-3 was significantly correlated with CRP, SAA, and ESR. Significant correlation of serum MMP-3 was found not only with DAS28 (CRP) in female and male patients (p <0.0001 and p < 0.0051, respectively) but also with the EULAR classification criteria for the disease activity of RA. Among the items of DAS28(CRP), the strongest association of MMP-3 was found with swollen joint counts. Furthermore, MMP-3 levels increased with advances in Stage and Class of RA. MMP-3 levels gradually decreased 12 and 24 weeks after successful treatment with MTX (p=0.0188 and p=0.0179, respectively). Extent of the decrease was more prominent in patients with better response to MTX than in those with poor response. MMP-3 levels significantly decreased 6 weeks after IFX treatment and continued to decrease until 48 weeks. Significant decrease of MMP-3 level from before treatment was shown only in the good response group to IFX after 48 weeks of treatment. MMP-3 level was shown to be useful as a disease activity marker in RA patients. In addition, serial measurement of MMP-3 maybe helpful to evaluate the effect of treatments with MTX and IFX.

A large-sized bubbling appearance of the glomerular basement membrane in a patient with pulmonary limited AL amyloidosis and a past history of lupus nephritis.

We report an unusual pathological finding, a large-sized bubbling appearance of the glomerular basement membrane (GBM), in a patient with pulmonary limited AL amyloidosis and a past history of lupus nephritis. The first renal biopsy specimen from 10 years ago, when systemic lupus erythematosus was diagnosed, demonstrated mild mesangial proliferation and subepithelial deposits (WHO classification: III + V). Light microscopy of the current biopsy using periodic acid methenamine silver (PAMS) stain demonstrated a large-sized bubbling appearance of the GBM; however, very weak immunoglobulin and complement deposition was observed in immunofluorescence studies. Routine electron microscopy demonstrated partial subendothelial expansion with electron-lucent materials, but no electron-dense deposits or amyloid fibrils. Electron microscopy with PAMS stain revealed electron-lucent endothelial scalloping, including some cellular components and microspheres in the GBM; however, it is not clear if these materials are derived from endothelial cells. One possibility is that these unique findings represent a recovery phase of lupus membranous nephritis; another is that these findings correspond to a new disease entity.

An IgA1-lambda-type monoclonal immunoglobulin deposition disease associated with membranous features in a patient with chronic hepatitis C viral infection and rectal cancer.

A 61-year-old man infected with hepatitis C virus developed urinary protein. Two-dimensional electrophoresis and immunoblotting of sera revealed no monoclonal proteins. Light microscopy and immunofluorescence of a kidney biopsy specimen demonstrated bubbling appearance and formation of spikes, associated with predominantly IgA1-lambda deposition, but not IgG, along glomerular capillary walls. Electron microscopy showed electron-dense deposits without any fibrillary structure located in the glomerular basement membrane. Seven months after the kidney biopsy, the patient had a surgical operation for rectal cancer. One year later, the urinary protein was still present. The present case is the first report of an IgA1-lambda-type monoclonal immunoglobulin deposition disease associated with membranous features.

[Three cases of drug-induced akathisia due to antiemetics during cancer palliative care].

Three cases of drug-induced akathisia during palliative care in terminal cancer patients were reported. Antiemetics (metoclopramide and prochlorperazine) possessing a central antidopaminergic effect were suspected to have caused the akathisia. Akathisia, as well as extrapyramidal symptoms, is a common and unpleasant complex neurobehavioral adverse effect of conventional antipsychotic drugs. But it is not widely recognized by general clinicians. This syndrome consists of subjective (feeling of inner restlessness, mental unease, or dysphoria and the urge to move) and objective components (restless movement, including rocking on one's feet, walking in position shuffling and tramping the legs,and crossing and uncrossing one's legs while sitting). In severe cases, patients constantly pace up and down in an attempt to relieve the sense of unrest. While the pathophysiology of drug-induced akathisia remains unknown, antagonism of the mesocortical and mesolimbic dopaminergic pathways is a plausible if not completely satisfactory hypothesis. The notion that dopaminergic blockade underlies the emergence of akathisia is supported by the PET studies. Since akathisia is a drug-induced adverse effect, optimal management involves its prevention rather than treatment. Drugs which have been found to have some efficacy in the treatment of akathisia are anticholinergics, beta-blockers, benzodiazepines and clonidine. Though a number of other treatments have been proposed, no trial-based evidences for treatment of akathisia have been available. It is important that akathisia is recognized and treated appropriately as an adverse reaction to drugs and a further increase in antipsychotic medication dosage may further exacerbate the condition.