Virtual Reality Images of the Home Are Useful for Patients With Hospital-Based Palliative Care: Prospective Observational Study With Analysis by Text Mining.

Background: Malignancy patients who need long-term hospitalization can feel loneliness affecting their quality of life. The global COVID-19 pandemic has caused visiting restrictions that could mean patients who might be missing out on family support and palliative care, therefore, need to adapt and change. We used virtual reality (VR) technology with the aim of reducing feelings of loneliness among these patients. Objectives: In a small cohort setting, we aimed to clarify the usefulness of VR viewing for this purpose by text mining interviews with the patients in palliative care after their VR experience, and to clarify the feasibility of this program. Design and Setting/Subjects: Four consecutive Japanese patients in the palliative care unit viewed personalized familiar persons or places through VR goggles, while communicating by telephone. After the VR experience, text mining of the patients' interviews was used to extract the words for the frequency count and co-occurrence analysis. Results: Four clusters were extracted: "relief from the pain of hospitalization by feeling safe and secure with family members nearby," "using VR to regain daily life," "immersive feeling of being in the same space as family," and "loneliness due to the realistic feeling of separation from the family through VR experience." There were no cases of VR sickness. Conclusion: Our results attained by text mining suggest the promising potential of VR imaging of familiar surroundings for patients in palliative care.

Assessment of metabolic activation of felbamate in chimeric mice with humanized liver in combination with in vitro metabolic assays.

Felbamate (FBM) is an antiepileptic drug that has minimal toxicity in preclinical toxicological species but has a serious idiosyncratic drug toxicity (IDT) in humans. The formation of reactive metabolites is common among most drugs associated with IDT, and 2-phenylpropenal (2-PP) is believed to be the cause of IDT by FBM. It is important to consider the species difference in susceptibility to IDT between experimental animals and humans. In the present study, we used an in vitro and in vivo model system to reveal species difference in IDT of FBM. Human cytochrome P450 (CYP) and carboxylesterase (CES) expressing microsomes were used to clarify the isozymes involved in the metabolism of FBM. The remaining amount of FBM was significantly reduced in incubation with microsomes expressing human CYP2C8, 2C9, 2E1, and CES1c isozymes. Chimeric mice with humanized liver are expected to predict IDT in humans. Therefore, metabolite profiles in chimeric mice with humanized liver were investigated after administration of FBM. Metabolites after glutathione (GSH) conjugation of 2-phenylpropenal (2-PP), which is the reactive metabolite responsible for FBM-induced IDT, were detected in chimeric mice plasma and liver homogenate. Mass spectrometry imaging (MSI) visualizes distribution of FBM and endogenous GSH, and GSH levels in human hepatocyte were decreased after administration of FBM. In this study, we identified CYP and CES isozymes involved in the metabolism of FBM and confirmed reactive metabolite formation and subsequent decrease in GSH using humanized animal model. These results would provide useful information for the susceptibility to IDT between experimental animals and humans.

Predictability of human pharmacokinetics of drugs that undergo hepatic organic anion transporting polypeptide (OATP)-mediated transport using single-species allometric scaling in chimeric mice with humanized liver: integration with hepatic drug metabolism.

We previously reported a prediction method for human pharmacokinetics (PK) using single species allometric scaling (SSS) and the complex Dedrick plot in chimeric mice with humanized liver to predict the total clearance (CLt), distribution volumes in steady state (Vdss) and plasma concentration-time profiles of several drugs metabolized by cytochrome P450 (P450) and non-P450 enzymes. In the present study, we examined eight compounds (bosentan, cerivastatin, fluvastatin, pitavastatin, pravastatin, repaglinide, rosuvastatin, valsartan) as typical organic anion transporting polypeptide (OATP) substrates and six compounds metabolized by P450 and non-P450 enzymes to evaluate the predictability of CLt, Vdss and plasma concentration-time profiles after intravenous administration to chimeric mice. The predicted CLt and Vdss of drugs that undergo OATP-mediated uptake and P450/non-P450-mediated metabolism reflected the observed data from humans within a threefold error range. We also examined the possibility of predicting plasma concentration-time profiles of drugs that undergo OATP-mediated uptake using the complex Dedrick plot in chimeric mice. Most profiles could be superimposed with observed profiles from humans within a two- to threefold error range. PK prediction using SSS and the complex Dedrick plot in chimeric mice can be useful for evaluating drugs that undergo both OATP-mediated uptake and P450/non-P450-mediated metabolism.

Activation of PXR, CAR and PPARα by pyrethroid pesticides and the effect of metabolism by rat liver microsomes.

In this study, we used reporter gene assays in COS-1 cells to examine the activation of rat pregnane X receptor (PXR), rat constitutive androstane receptor (CAR) and rat peroxisome-proliferator activated receptor (PPAR)α by pyrethroid pesticides, and to understand the effects of metabolic modification on their activities. All eight pyrethroids tested in this study showed rat PXR agonistic activity; deltamethrin was the most potent, followed by cis-permethrin and cypermethrin. However, when the pyrethroids were incubated with rat liver microsomes, their rat PXR activities were decreased to various extents. Cis- and trans-permethrin showed weak rat CAR agonistic activity, while the other pyrethroids were inactive. However, fenvalerate showed dose-dependent inverse agonistic activity toward rat CAR, and this activity was reduced after metabolism. None of the pyrethroids showed rat PPARα agonistic activity, but a metabolite of cis-/trans-permethrin and phenothrin, 3-phenoxybenzoic acid, activated rat PPARα. Since PXR, CAR and PPARα regulate various xenobiotic/endobiotic-metabolizing enzymes, activation of these receptors by pyrethroids may result in endocrine disruption due to changes of hormone-metabolizing activities.

Coordinated cytochrome P450 expression in mouse liver and intestine under different dietary conditions during liver regeneration after partial hepatectomy.

Liver resection is performed to remove tumors in patients with liver cancer, but the procedure's suitability depends on the regenerative ability of the liver. It is important to consider the effects of exogenous factors, such as diets, on liver regeneration for the recovery of function. The evaluation of drug metabolism during liver regeneration is also necessary because liver dysfunction is generally observed after the operation. Here, we investigated the influence of a purified diet (AIN-93G) on liver regeneration and changes in the mRNA expression of several cytochrome P450 (CYP) isoforms in the liver and small intestine using a two-thirds partial hepatectomy (PH) mouse model fed with a standard diet (MF) and a purified diet. Liver regeneration was significantly delayed in the purified diet group relative to that in the standard diet group. The liver Cyp2c55 and Cyp3a11 expression was increased at 3 day after PH especially in the purified diet group. Bile acid may partly cause the differences in liver regeneration and CYP expression between two types of diets. On the other hand, Cyp3a13 expression in the small intestine was transiently increased at day 1 after PH in both diet groups. The findings suggest that compensatory induction of the CYP expression occurred in the small intestine after attenuation of drug metabolism potential in the liver. The present results highlight the importance of the relationship between liver regeneration, drug metabolism, and exogenous factors for the effective treatment, including surgery and medication, in patients after liver resection or transplantation.

Comparison of Drug Metabolism and Its Related Hepatotoxic Effects in HepaRG, Cryopreserved Human Hepatocytes, and HepG2 Cell Cultures.

Differentiated HepaRG cells maintain liver-specific functions such as drug-metabolizing enzymes. In this study, the feasibility of HepaRG cells as a human hepatocyte model for in vitro toxicity assessment was examined using selected hepatotoxic compounds. First, basal drug-metabolizing enzyme activities (CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP3A4, uridine 5'-diphospho-glucuronosyltransferase [UGT], and sulfotransferases [SULT]) were measured in HepaRG, human hepatocytes, and HepG2 cells. Enzyme activities in differentiated HepaRG cells were comparable to those in human hepatocytes and much higher than those in HepG2 cells, except for SULT activity. Second, we examined the cytotoxicity of hepatotoxic compounds, acetaminophen (APAP), aflatoxin B1 (AFB1), cyclophosphamide (CPA), tamoxifen (TAM), and troglitazone (TGZ) in HepaRG cells and human hepatocytes. AFB1- and CPA-induced cytotoxicities against HepaRG cells were comparable to those against human hepatocytes. Furthermore, the cytotoxicities of these compounds were inhibited by 1-aminobenzotriazole (ABT), a broad CYP inhibitor, in both cells and were likely mediated by metabolic activation by CYP. Finally, toxicogenomics analysis of HepG2 and HepaRG cells after exposure to AFB1 and CPA revealed that numerous p53-related genes were upregulated- and the expression of these genes was greater in HepaRG than in HepG2 cells. These results suggest that gene expression profiles of HepaRG cells were affected more considerably by the toxic mechanisms of AFB1 and CPA than the profiles of HepG2 cells were. Therefore, our investigation shows that HepaRG cells could be useful human hepatic cellular models for toxicity studies.

Tributyltin induces epigenetic changes and decreases the expression of nuclear respiratory factor-1.

Tributyltin (TBT), a common organotin environmental pollutant, has been widely used as a component of marine antifouling paints. We previously reported that exposure to TBT inhibits the expression and DNA binding of nuclear respiratory factor-1 (NRF-1) and causes neurotoxicity. In the present study, we focused on the epigenetic effects of TBT and investigated whether TBT decreases NRF-1 expression via epigenetic modifications in SH-SY5Y human neuroblastoma cells. First, we found that exposure to 300 nM TBT decreases NRF-1 expression. We examined epigenetic changes induced by TBT, and showed that TBT causes hypermethylation of the NRF-1 promoter region, increases the amount of methyl-CpG-binding protein 2 (MeCP2) bound to the NRF-1 promoter, and alters the expression of DNA methyltransferases and ten-eleven translocation (TET) demethylation enzymes. These results suggest that epigenetic changes play an important role in regulation of NRF-1 expression. Next, we investigated effect of NRF-1 expression decrease on cells, and TBT reduces mitochondrial membrane potential and overexpression of NRF-1 rescued this reduction in membrane potential. Thus, we suggested that NRF-1 is important for maintaining mitochondrial membrane potential. Our study indicates that TBT causes epigenetic changes such as hypermethylation, which increases recruitment of MeCP2 to the NRF-1 promoter and probably lead to decreased of NRF-1 expression and mitochondrial membrane potential. Therefore, this research provides new evidence of the epigenetic action caused by organotin.

Mild MPP+ exposure-induced glucose starvation enhances autophagosome synthesis and impairs its degradation.

Parkinson's disease (PD) is a prevalent neurodegenerative disorder, mainly characterised by the progressive loss of dopaminergic neurons. MPP+ has been widely used as a PD-related neurotoxin, and their reports suggested the several hypotheses for neuronal cell death. However, most of these hypotheses come from the studies about the acute MPP+ exposure. We previously revealed that mild MPP+ exposure (10 and 200 µM), which induces gradual cell death, impairs autophagosome degradation at 48 h. In the present study, we further investigated the specific events of mild MPP+ exposure and revealed that mild MPP+ exposure causes the cell death through glucose starvation, but not acute toxic model (2.5 and 5 mM). At 36 h after mild MPP+ exposure, autophagosome synthesis was enhanced owing to glucose starvation and continued to enhance until 48 h, despite impaired autophagosome degradation. Inhibition of autophagosome synthesis reduced mild MPP+-induced cell death. In conclusion, we clarified that glucose starvation-enhanced autophagosome synthesis occurs at an earlier stage than impaired autophagosome degradation and is important in mild MPP+ toxicity.

Acetaminophen analog N-acetyl-m-aminophenol, but not its reactive metabolite, N-acetyl-p-benzoquinone imine induces CYP3A activity via inhibition of protein degradation.

Cytochrome P450 (CYP) 3A subfamily members are known to metabolize various types of drugs, highlighting the importance of understanding drug-drug interactions (DDI) depending on CYP3A induction or inhibition. While transcriptional regulation of CYP3A members is widely understood, post-translational regulation needs to be elucidated. We previously reported that acetaminophen (APAP) induces CYP3A activity via inhibition of protein degradation and proposed a novel DDI concept. N-Acetyl-p-benzoquinone imine (NAPQI), the reactive metabolite of APAP formed by CYP, is known to cause adverse events related to depletion of intracellular reduced glutathione (GSH). We aimed to inspect whether NAPQI rather than APAP itself could cause the inhibitory effects on protein degradation. We found that N-acetyl-l-cysteine, the precursor of GSH, and 1-aminobenzotriazole, a nonselective CYP inhibitor, had no effect on CYP3A1/23 protein levels affected by APAP. Thus, we used APAP analogs to test CYP3A1/23 mRNA levels, protein levels, and CYP3A activity. We found N-acetyl-m-aminophenol (AMAP), a regioisomer of APAP, has the same inhibitory effects of CYP3A1/23 protein degradation, while p-acetamidobenzoic acid (PAcBA), a carboxy-substituted form of APAP, shows no inhibitory effects. AMAP and PAcBA cannot be oxidized to quinone imine forms such as NAPQI, so the inhibitory effects could depend on the specific chemical structure of APAP.

In vitro metabolism of methiocarb and carbaryl in rats, and its effect on their estrogenic and antiandrogenic activities.

In this work, we examined the metabolism of the carbamate insecticides methiocarb and carbaryl by rat liver microsomes and plasma, and its effect on their endocrine-disrupting activities. Methiocarb and carbaryl were not enzymatically hydrolyzed by rat liver microsomes, but were hydrolyzed by rat plasma, mainly to methylthio-3,5-xylenol (MX) and 1-naphthol, respectively. When methiocarb was incubated with rat liver microsomes in the presence of NADPH, methiocarb sulfoxide was formed. The hydrolysis product, MX, was also oxidized to the sulfoxide, 3,5-dimethyl-4-(methylsulfinyl)phenol (SP), by rat liver microsomes in the presence of NADPH. These oxidase activities were catalyzed by cytochrome P450 and flavin-containing monooxygenase. Methiocarb and carbaryl both exhibited estrogen receptor α (ERα) and ERß agonistic activity. MX and 1-naphthol showed similar activities, but methiocarb sulfoxide and SP showed markedly decreased activities. On the other hand, methiocarb and carbaryl exhibited potent antiandrogenic activity in the concentration range of 1×10(-6)-3×10(-5) M. Their hydrolysis products, MX, and 1-naphthol also showed high activity, equivalent to that of flutamide. However, methiocarb sulfoxide and SP showed relatively low activity. Thus, hydrolysis of methiocarb and carbaryl and oxidation of methiocarb to the sulfoxide markedly modified the estrogenic and antiandrogenic activities of methiocarb and carbaryl.

Mutation-Independent Activation of the Anaplastic Lymphoma Kinase in Neuroblastoma.

Activating mutations of anaplastic lymphoma kinase (ALK) have been identified as important players in neuroblastoma development. Our goal was to evaluate the significance of overall ALK activation in neuroblastoma. Expression of phosphorylated ALK, ALK, and its putative ligands, pleiotrophin and midkine, was screened in 289 neuroblastomas and 56 paired normal tissues. ALK was expressed in 99% of tumors and phosphorylated in 48% of cases. Pleiotrophin and midkine were expressed in 58% and 79% of tumors, respectively. ALK activation was significantly higher in tumors than in paired normal tissues, together with ALK and midkine expression. ALK activation was largely independent of mutations and correlated with midkine expression in tumors. ALK activation in tumors was associated with favorable features, including a younger age at diagnosis, hyperdiploidy, and detection by mass screening. Antitumor activity of the ALK inhibitor TAE684 was evaluated in wild-type or mutated ALK neuroblastoma cell lines and xenografts. TAE684 was cytotoxic in vitro in all cell lines, especially those harboring an ALK mutation. TAE684 efficiently inhibited ALK phosphorylation in vivo in both F1174I and R1275Q xenografts but demonstrated antitumor activity only against the R1275Q xenograft. In conclusion, ALK activation occurs frequently during neuroblastoma oncogenesis, mainly through mutation-independent mechanisms. However, ALK activation is not associated with a poor outcome and is not always a driver of cell proliferation and/or survival in neuroblastoma.

[Aryl Hydrocarbon Receptor Ligand Activity of Extracts from 62 Herbal Medicines and Effect on Cytochrome P450 Activity].

Aryl hydrocarbon receptor (AhR) ligand activity of the extracts of 62 herbal medicines was examined using yeast reporter assay. Fifty-eight herbal extracts exhibited AhR ligand activity. The highest activity was observed with Ogon (Scutellariae Radix), followed by Oren (Coptidis Rhizoma), Kujin (Sophorae Radix) and Shoma (Cimicifiigae Rhizoma). When these extracts were treated with hesperinase, a hydrolase for sugar conjugates, the aglycones showed higher activity than the parent extracts. Among the constituents of Ogon extract, baicalein and wogonin showed AhR ligand activity, while the sugar conjugate of baicalein, baicalin, was inactive. Among the flavonoid components of these herbal medicines, flavone and chrysin exhibited high ligand activity for AhR. Ethoxyresorufin O-dealkylase (EROD) activity due to CYP1A1 in HepG2 cells was enhanced by the addition of baicalein. Baicalein also decreased the 3-methylcholanthrene-induced increase of EROD activity, but this effect was not statistically significant. When wogonin or baicalein was orally administered at the dose of 100 mg/kg to mice, EROD activity in liver was only slightly changed. Furthermore, when Ogon extract was co-administered with 3-methylcholanthrene, the EROD and methoxyresorufin O-dealkylase activities were not significantly changed. These results indicate that many herbal extracts have AhR ligand activity, and their inducing effect on CYP1A1/2 can be evaluated in HepG2 cells.

Advanced childhood testicular yolk sac tumor with bone metastasis: a case report.

We report a case of advanced childhood testicular yolk sac tumor with bone metastasis, which was successfully treated by multimodal treatment. Optimal management of bone metastases from testicular yolk sac tumor in childhood is discussed.

Detection of a novel neurotoxic metabolite of Parkinson's disease-related neurotoxin, 1-benzyl-1,2,3,4- tetrahydroisoquinoline.

Naturally occurring low-molecular weight compounds with a chemical structure like that of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, such as 1-benzyl-1,2,3,4-tetrahydroisoquinoline(1BnTIQ), are candidates for the endogenous neurotoxins that cause Parkinson's disease (PD). 1BnTIQ is an endogenous amine in human CSF and increases in the CSF of patients with PD. It inhibits complex Iand elicits PD-like behavioral abnormalities in monkey and mouse. In this study, we searched metabolites of 1BnTIQ by rat liver S9 using liquid chromatography-tandem mass spectrometry, and identified a dehydrated metabolite, 1-benzyl-3,4-dihydroisoquinoline (1BnDIQ). 1BnDIQ was identified by corresponding mass spectra and precursor ion scans in authentic and complete enzyme samples. Multiple reaction monitoring analysis showed microsome-dependent 1BnDIQ production. We previously reported that 1BnDIQ is more toxic than 1BnTIQ in cytotoxicity study in SH-SY5Y neuroblastoma cells. In addition, 1BnTIQ is reported to pass through the blood-brain barrier of the rat brain, and 1BnDIQ is supposed to be more lipophilic than 1BnTIQ. 1BnDIQ may easily reach the brain, and it might contribute to PD-related neurotoxicity.

Fluorometric assessment of acetaminophen-induced toxicity in rat hepatocyte spheroids seeded on micro-space cell culture plates.

Hepatotoxicity induced by the metabolic activation of drugs is a major concern in drug discovery and development. Three-dimensional (3-D) cultures of hepatocyte spheroids may be superior to monolayer cultures for evaluating drug metabolism and toxicity because hepatocytes in spheroids maintain the expression of various metabolizing enzymes and transporters, such as cytochrome P450 (CYP). In this study, we examined the hepatotoxicity due to metabolic activation of acetaminophen (APAP) using fluorescent indicators of cell viability and intracellular levels of glutathione (GSH) in rat hepatocyte spheroids grown on micro-space cell culture plates. The mRNA expression levels of some drug-metabolizing enzymes were maintained during culture. Additionally, this culture system was compatible with microfluorometric imaging under confocal laser scanning microscopy. APAP induced a decrease in intracellular ATP at 10mM, which was blocked by the CYP inhibitor 1-aminobenzotriazole (ABT). APAP (10mM, 24h) decreased the levels of both intracellular ATP and GSH, and GSH-conjugated APAP (APAP-GSH) were formed. All three effects were blocked by ABT, confirming a contribution of APAP metabolic activation by CYP to spheroid toxicity. Fluorometric imaging of hepatocyte spheroids on micro-space cell culture plates may allow the screening of drug-induced hepatotoxicity during pharmaceutical development.

Endogenous neurotoxic dopamine derivative covalently binds to Parkinson's disease-associated ubiquitin C-terminal hydrolase L1 and alters its structure and function.

Parkinson's disease (PD) is a common neurodegenerative disease, but its pathogenesis remains elusive. A mutation in ubiquitin C-terminal hydrolase L1 (UCH-L1) is responsible for a form of genetic PD which strongly resembles the idiopathic PD. We previously showed that 1-(3',4'-dihydroxybenzyl)-1,2,3,4-tetrahydroisoquinoline (3',4'DHBnTIQ) is an endogenous parkinsonism-inducing dopamine derivative. Here, we investigated the interaction between 3',4'DHBnTIQ and UCH-L1 and its possible role in the pathogenesis of idiopathic PD. Our results indicate that 3',4'DHBnTIQ binds to UCH-L1 specifically at Cys152 in vitro. In addition, 3',4'DHBnTIQ treatment increased the amount of UCH-L1 in the insoluble fraction of SH-SY5Y cells and inhibited its hydrolase activity to 60%, reducing the level of ubiquitin in the soluble fraction of SH-SY5Y cells. Catechol-modified UCH-L1 as well as insoluble UCH-L1 were detected in the midbrain of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated PD model mice. Structurally as well as functionally altered UCH-L1 have been detected in the brains of patients with idiopathic PD. We suggest that conjugation of UCH-L1 by neurotoxic endogenous compounds such as 3',4'DHBnTIQ might play a key role in onset and progression of idiopathic PD. We investigated the interaction between ubiquitin C-terminal hydrolase L1 (UCH-L1) and the brain endogenous parkinsonism inducer 1-(3',4'-dihydroxybenzyl)-1,2,3,4-tetrahydroisoquinoline (3',4'DHBnTIQ). Our results indicate that 3',4'DHBnTIQ binds to UCH-L1 specifically at cysteine 152 and induces its aggregation. 3',4'DHBnTIQ also inhibits the hydrolase activity of UCH-L1. Catechol-modified as well as insoluble UCH-L1 were detected in the midbrains of MPTP-treated Parkinson's disease (PD) model mice. Conjugation of UCH-L1 by neurotoxic endogenous compounds like 3',4'DHBnTIQ might play a key role in onset and progression of PD.

In vitro metabolism of cis- and trans-permethrin by rat liver microsomes, and its effect on estrogenic and anti-androgenic activities.

Permethrin is a widely applied broad-spectrum pyrethroid insecticide that consists of a mixture of cis- and trans-isomers. We examined the changes of estrogenic and anti-androgenic activities resulting from metabolism of the isomers. Both cis- and trans-permethrin were hydrolyzed to 3-phenoxybenzyl alcohol (PBAlc) by rat liver microsomes, but the extent of hydrolysis of trans-permethrin was much greater than that of the cis-isomer. In the presence of NADPH, PBAlc was further transformed to 4'-hydroxylated PBAlc (4'-OH PBAlc), 3-phenoxybenzaldehyde (PBAld) and 3-phenoxybenzoic acid (PBAcid). cis-Permethrin, but not trans-permethrin, also afforded its 4'-hydroxylated derivative (4'-OH cis-permethrin). trans-Permethrin was an anti-androgen, but also showed weak estrogenic activity, while cis-permethrin was a weak estrogen and a weak anti-androgen. After incubation with rat liver microsomes in the presence of NADPH, cis-permethrin but not trans-permethrin was metabolically activated for estrogenic activity. On the other hand, estrogenic activity of trans-permethrin was not changed, but its anti-androgenic activity was enhanced after incubation. 4'-OH PBAlc and PBAlc showed estrogenic activity, while PBAld and PBAlc showed anti-androgenic activity. PBAcid showed neither activity. 4'-OH cis-permethrin showed both estrogenic and anti-androgenic activities. Overall, our results indicate that permethrin is metabolically activated for estrogenic and anti-androgen activities, and the microsomal transformation of permethrin to 4'-OH cis-permethrin, 4'-OH PBAlc and PBAlc contributes to the both metabolic activations.

Prognostic factors of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in children: report of the Japan Histiocytosis Study Group.

BACKGROUND: Despite several advances in the treatment of Epstein-Barr virus (EBV) in recent years, patients with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) do not always show satisfactory outcomes. We here conducted a nationwide survey in Japan to identify prognostic factors of EBV-HLH in children with this disease in an effort to improve the management and the outcomes of these patients. PROCEDURE: Between January 2003 and June 2008, we enrolled 98 children younger than 18 years of age who were diagnosed with EBV-HLH. We then studied the clinical characteristics and laboratory findings at the time of diagnosis with the aim to identify prognostic factors for EBV-HLH. RESULTS: The mean age of onset of EBV-HLH was 3.9 ± 2.8 years. Most of our patients presented with fever, hepatosplenomegaly, lymphadenopathy, and hemophagocytosis of bone marrow. Sixty-two percent of patients showed T cell clonality, and 97% had EBV infection in either T or natural killer cells. Most patients (60%) were treated with a multi-agent chemotherapeutic regimen, including corticosteroid, etoposide, and cyclosporine. After initial treatment, 90.3% of patients were in remission, and 7 patients (8.2%) experienced recurrence of EBV infection. Among several prognostic factors, patients with both hyperbilirubinemia (>1.8 mg/dl) and hyperferritinemia (>20,300 ng/ml) at the time of diagnosis had significantly poorer outcomes than those with low serum bilirubin and ferritin levels. CONCLUSIONS: These findings suggest that the therapeutic strategy for children with EBV-HLH could be tailored according to the laboratory findings at diagnosis.

Genome-wide approach to identify second gene targets for malignant rhabdoid tumors using high-density oligonucleotide microarrays.

Malignant rhabdoid tumor (MRT) is a rare and highly lethal cancer that mainly affects infants and young children. The majority of MRT are characterized by loss of function of SMARCB1 on chromosome 22q11.2. However, little is known about genetic changes other than SMARCB1 alterations that are responsible for the development and/or progression of MRT. To explore additional gene targets in MRT, we analyzed 21 MRT specimens (12 fresh tumors and 9 MRT-derived cell lines) using high-density single nucleotide polymorphism genotyping microarrays. Although MRT genomes are characterized by common 22q11.2 deletions, affecting the SMARCB1 locus with a frequency of 95.2% (20/21 specimens), other genetic changes have been less frequent. Of the 20 specimens with deletions of 22q11.2, eight specimens showed uniparental disomy of the SMARCB1 locus with homozygous deletions or gene mutations. High-resolution analysis also disclosed the recurrent hemizygous/homozygous deletions of 7q35-q36.1, involving the CNTNAP2 locus in three specimens. Mutations analysis of CNTNAP2 showed a novel R157C missense mutation in a primary case, and methylation analysis showed recurrent hypermethylation of CNTNAP2 in three of nine cell lines. These results demonstrated that CNTNAP2 is one of the additional gene targets, other than SMARCB1, in MRT.

Clinical characteristics and outcomes of chédiak-Higashi syndrome: a nationwide survey of Japan.

BACKGROUND: Chédiak-Higashi syndrome (CHS) is a rare autosomal recessive disorder characterized by immunodeficiency, neurological dysfunction, and oculocutaneous albinism. Recently, several clinical CHS phenotypes have been reported. Here, we report results of a nationwide survey performed to clarify clinical characteristics and outcomes of CHS patients in Japan. METHODS: Questionnaires were sent to 287 institutions to collect data regarding CHS patients diagnosed between 2000 and 2010, including results of lysosomal trafficking regulator (LYST) gene analysis. Cytotoxicity and degranulation activity of cytotoxic T lymphocytes were analyzed in available patient samples. RESULTS: A total of 15 patients diagnosed with CHS were eligible for enrollment in this study. Of these, 10 (67%) had recurrent bacterial infections, five (33%) developed life-threatening hemophagocytic lymphohistiocytosis (HLH), and one patient had complicated malignant lymphoma. Hematopoietic stem cell transplantation (HSCT) was performed for six patients including three with HLH, and 10 of the enrolled patients have survived at the time of this writing. LYST analysis was performed for 10 patients; seven different mutations were detected in seven patients, whereas no mutation was identified in three patients. Cytotoxicity and degranulation activity were impaired in patients with and without LYST mutation. DISCUSSION: Results of this survey indicate that one or two patients with CHS were newly diagnosed each year in Japan. The incidence of HLH was not as high as expected. Mutations of genes other than LYST were suspected in some cases. We conclude that determining indication for HSCT for CHS patients should be based on genetic and cytotoxic analysis.