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1.
Cancer Sci ; 113(10): 3362-3375, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35851737

ABSTRACT

Women who are heterozygous for deleterious BRCA1 germline mutations harbor a high risk of hereditary breast cancer. Previous Brca1-heterozygous animal models do not recapitulate the breast cancer phenotype, and thus all currently used knockout models adopt conditional, mammary-specific homozygous Brca1 loss or addition of Trp53 deficiency. Herein, we report the creation and characterization of a novel Brca1 mutant rat model harboring the germline L63X mutation, which mimics a founder mutation in Japan, through CRISPR-Cas9-based genome editing. Homozygotes (Brca1L63X/L63X ) were embryonic lethal, whereas heterozygotes (Brca1L63X/+ ) showed apparently normal development. Without carcinogen exposure, heterozygotes developed mammary carcinoma at a comparable incidence rate with their wild-type (WT) littermates during their lifetime. Intraperitoneal injection of 1-methyl-1-nitrosourea (25 or 50 mg/kg) at 7 weeks of age induced mammary carcinogenesis at comparable levels among the heterozygotes and their littermates. After exposure to ionizing radiation (0.1-2 Gy) at 7 weeks of age, the heterozygotes, but not WT littermates, displayed dose-dependent mammary carcinogenesis with 0.8 Gy-1 excess in hazard ratio during their middle age; the relative susceptibility of the heterozygotes was more prominent when rats were irradiated at 3 weeks of age. The heterozygotes had tumors with a lower estrogen receptor α immunopositivity and no evidence of somatic mutations of the WT allele. The Brca1L63X/+ rats thus offer the first single-mutation, heterozygous model of BRCA1-associated breast cancer, especially with exposure to a DNA break-inducing carcinogen. This implies that such carcinogens are causative and a key to breast cancer prevention in individuals who carry high-risk BRCA1 mutations.


Subject(s)
Breast Neoplasms , Neoplasms, Radiation-Induced , Animals , BRCA1 Protein/genetics , Breast Neoplasms/genetics , Carcinogens , Cell Transformation, Neoplastic , Estrogen Receptor alpha/genetics , Female , Germ-Line Mutation , Humans , Middle Aged , Neoplasms, Radiation-Induced/genetics , Rats
2.
EMBO Rep ; 19(11)2018 11.
Article in English | MEDLINE | ID: mdl-30213795

ABSTRACT

Glioblastoma is one of the most aggressive forms of cancers and has a poor prognosis. Genomewide analyses have revealed that a set of core signaling pathways, the p53, RB, and RTK pathways, are commonly deregulated in glioblastomas. However, the molecular mechanisms underlying the tumorigenicity of glioblastoma are not fully understood. Here, we show that the lysine deacetylase SIRT2 is required for the proliferation and tumorigenicity of glioblastoma cells, including glioblastoma stem cells. Furthermore, we demonstrate that SIRT2 regulates p73 transcriptional activity by deacetylation of its C-terminal lysine residues. Our results suggest that SIRT2-mediated inactivation of p73 is critical for the proliferation and tumorigenicity of glioblastoma cells and that SIRT2 may be a promising molecular target for the therapy of glioblastoma.


Subject(s)
Brain Neoplasms/pathology , Glioblastoma/pathology , Sirtuin 2/metabolism , Tumor Protein p73/metabolism , Acetylation , Animals , Apoptosis/drug effects , Apoptosis/genetics , Brain Neoplasms/metabolism , Cell Proliferation , Furans/pharmacology , Gene Knockdown Techniques , Glioblastoma/metabolism , Humans , Lysine/metabolism , Mice, Nude , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Quinolines/pharmacology , Sirtuin 2/antagonists & inhibitors , Sirtuin 2/genetics , Tumor Cells, Cultured , Tumor Protein p73/genetics , Xenograft Model Antitumor Assays
3.
Radiat Environ Biophys ; 59(4): 711-721, 2020 11.
Article in English | MEDLINE | ID: mdl-32996008

ABSTRACT

As classical transplantation repopulation assays for studying the radiobiology of rat mammary stem/progenitor cells are extremely time-consuming, this study aimed to characterize the radiobiological properties of mammospheres, spherical clumps of mammary cells formed under non-adherent culture conditions, which are a simple and widely used technique for assessing progenitor cell activity. Rat mammary cells were dissociated and used in transplantation repopulation assays and for the formation of mammospheres. Immunofluorescence for cytokeratin 14 and 18 was used to identify basal and luminal mammary epithelial cells, respectively. Incorporation of 5-bromo-2'-deoxyuridine was used to evaluate cell proliferation. The repopulating activity of the transplanted primary rat mammary cells demonstrated their radiosensitivity, reproducing previous data, with a significant reduction in repopulating activity at ≥ 2 Gy. Cells constituting rat mammospheres were positive for either cytokeratin 14 or 18, with occasional double-positive cells. Both proliferation and aggregation contributed to sphere formation. Cells obtained from the spheres showed lower repopulating activity after transplantation than primary cells. When primary cells were irradiated and then used for sphere formation, the efficiency of sphere formation was significantly decreased at 8 Gy but not at ≤ 6 Gy, indicating radioresistance of the formation process. Irradiation at 8 Gy reduced the proliferation of cells during sphere formation, whereas the cellular composition of the resulting spheres was unaffectes. Thus, mammosphere formation assays may measure a property of putative mammary progenitors that is different from what is measured in the classic transplantation repopulation assay in radiobiology.


Subject(s)
Cesium Radioisotopes , Epithelial Cells/radiation effects , Gamma Rays , Mammary Glands, Animal/cytology , Animals , Cell Aggregation , Cell Proliferation , Epithelial Cells/transplantation , Female , Radiation Tolerance , Rats, Inbred Lew , Rats, Transgenic
4.
Int J Cancer ; 143(2): 343-354, 2018 07 15.
Article in English | MEDLINE | ID: mdl-29435983

ABSTRACT

With the increase in the number of long-term cancer survivors worldwide, there is a growing concern about the risk of secondary cancers induced by radiotherapy. Epigenetic modifications of genes associated with carcinogenesis are attractive targets for the prevention of cancer owing to their reversible nature. To identify genes with possible changes in functionally relevant DNA methylation patterns in mammary carcinomas induced by radiation exposure, we performed microarray-based global DNA methylation and expression profiling in γ-ray-induced rat mammary carcinomas and normal mammary glands. The gene expression profiling identified dysregulation of developmentally related genes, including the downstream targets of polycomb repressive complex 2 (PRC2) and overexpression of enhancer of zeste homolog 2, a component of PRC2, in the carcinomas. By integrating expression and DNA methylation profiles, we identified ten hypermethylated and three hypomethylated genes that possibly act as tumor-suppressor genes and oncogenes dysregulated by aberrant DNA methylation; half of these genes encode developmental transcription factors. Bisulfite sequencing and quantitative PCR confirmed the dysregulation of the polycomb-regulated developmentally related transcription-factor genes Dmrt2, Hoxa7, Foxb1, Sox17, Lhx8, Gata3 and Runx1. Silencing of Hoxa7 was further verified by immunohistochemistry. These results suggest that, in radiation-induced mammary gland carcinomas, PRC2-mediated aberrant DNA methylation leads to dysregulation of developmentally related transcription-factor genes. Our findings provide clues to molecular mechanisms linking epigenetic regulation and radiation-induced breast carcinogenesis and underscore the potential of such epigenetic mechanisms as targets for cancer prevention.


Subject(s)
DNA Methylation/radiation effects , Gene Expression Profiling/methods , Mammary Neoplasms, Experimental/genetics , Neoplasms, Radiation-Induced/genetics , Sequence Analysis, DNA/methods , Animals , Enhancer of Zeste Homolog 2 Protein/genetics , Epigenesis, Genetic/radiation effects , Female , Gene Expression Regulation, Neoplastic/radiation effects , Oligonucleotide Array Sequence Analysis/methods , Polycomb Repressive Complex 2/genetics , Rats , Transcription Factors/genetics
5.
Gynecol Oncol ; 143(2): 246-251, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27612976

ABSTRACT

BACKGROUND: In clinical practice, 40mg/m2 of pegylated liposomal doxorubicin (PLD40) has been used as an initial dosage for treating recurrent epithelial ovarian cancer (OC) instead of the recommended dose of 50mg/m2 (PLD50). However, no robust evidence is available to support the use of PLD40. This post-hoc study aimed to compare the efficacy and safety of initial PLD dosages in propensity score (P-score)-matched dataset. METHODS: The data source was a PLD postmarketing surveillance dataset (n=2189) conducted in Japan. Eligibility criteria for the present study were as follows: recurrent OC, history of chemotherapy, and treatment with PLD monotherapy at a dosage between 35.5 and 54.4mg/m2. Overall survival (OS) was compared between PLD50- and PLD40-treated groups using the log-rank test. Incidences of palmar-plantar erythrodysesthesia (PPE) and stomatitis were also compared between the groups. RESULTS: Overall, 503 matched pairs were generated using P-score analysis. The median survival time with PLD50 and PLD40 was 383 and 350days, respectively, with a hazard ratio of 1.10 (95% confidence interval, 0.98-1.26; p=0.211), although the difference was not statistically significant in the P-score-matched dataset. However, the incidence and severity of PPE and stomatitis were significantly lower with PLD40. CONCLUSIONS: Our study showed that the efficacy of PLD did not differ based on initial dosages, but the risk of adverse events was reduced with PLD40. Considering the balance between patient benefits and risks, our results support the use of PLD40 in clinical practice.


Subject(s)
Antibiotics, Antineoplastic/therapeutic use , Doxorubicin/analogs & derivatives , Neoplasm Recurrence, Local/drug therapy , Neoplasms, Glandular and Epithelial/drug therapy , Ovarian Neoplasms/drug therapy , Propensity Score , Adolescent , Adult , Aged , Aged, 80 and over , Antibiotics, Antineoplastic/administration & dosage , Carcinoma, Ovarian Epithelial , Doxorubicin/administration & dosage , Doxorubicin/therapeutic use , Female , Humans , Middle Aged , Neoplasms, Glandular and Epithelial/mortality , Ovarian Neoplasms/mortality , Polyethylene Glycols/administration & dosage , Polyethylene Glycols/therapeutic use
6.
Biochem Biophys Res Commun ; 459(3): 411-5, 2015 Apr 10.
Article in English | MEDLINE | ID: mdl-25735981

ABSTRACT

Upon binding of a Wnt ligand to the frizzled (FZD)-low density lipoprotein receptor related protein 5/6 (LRP5/6) receptor complex, the ß-catenin destruction complex, composed of Axin1, adenomatous polyposis coli (APC), glycogen synthase kinase 3 (GSK3) and casein kinase 1 (CK1), is immediately inactivated, which causes ß-catenin stabilization. However, the molecular mechanism of signal transduction from the receptor complex to the ß-catenin destruction complex is controversial. Here we show that Wnt3a treatment promotes the dissociation of the Axin1-APC complex in glioblastoma cells cultured in serum-free medium. Experiments with the GSK3 inhibitor BIO suggest that Axin1-APC dissociation was controlled by phosphorylation. Introduction of a phosphomimetic mutation into Thr160 of Axin1, located in the APC-binding region RGS, abrogated the interaction of Axin1 with APC. Consistent with these observations, the Axin1 phosphomimetic mutant lost the ability to reduce ß-catenin stability and to repress ß-catenin/TCF-dependent transcription. Taken together, our results suggest a novel mechanism of Wnt signaling through the dissociation of the ß-catenin destruction complex by Axin1 Thr160 modification.


Subject(s)
Axin Protein/chemistry , Axin Protein/metabolism , Axin Signaling Complex/chemistry , Axin Signaling Complex/metabolism , Adenomatous Polyposis Coli Protein/chemistry , Adenomatous Polyposis Coli Protein/metabolism , Axin Protein/genetics , Binding Sites , Biomimetic Materials/chemistry , Biomimetic Materials/metabolism , Casein Kinase I/chemistry , Casein Kinase I/metabolism , Cell Line, Tumor , Glioblastoma/metabolism , Glycogen Synthase Kinase 3/chemistry , Glycogen Synthase Kinase 3/metabolism , HEK293 Cells , Humans , Low Density Lipoprotein Receptor-Related Protein-5/antagonists & inhibitors , Low Density Lipoprotein Receptor-Related Protein-5/genetics , Low Density Lipoprotein Receptor-Related Protein-5/metabolism , Low Density Lipoprotein Receptor-Related Protein-6/antagonists & inhibitors , Low Density Lipoprotein Receptor-Related Protein-6/genetics , Low Density Lipoprotein Receptor-Related Protein-6/metabolism , Mutagenesis, Site-Directed , Phosphorylation , Protein Stability , RNA, Small Interfering/genetics , Threonine/chemistry , Wnt Signaling Pathway , beta Catenin/chemistry , beta Catenin/metabolism
7.
Biochem Biophys Res Commun ; 460(2): 216-21, 2015 May 01.
Article in English | MEDLINE | ID: mdl-25770425

ABSTRACT

LGR5 plays an important role in the self-renewal of stem cells and is used as a marker identifying self-renewing stem cells in small intestine and hair follicles. Moreover, LGR5 has been reported to be overexpressed in several cancers. SOX9 is a transcription factor that plays a key role in development, differentiation and lineage commitment in various tissues. It has also been reported that SOX9 is overexpressed in a variety of cancers and contributes to their malignant phenotype. Here we show that LGR5 is required for the tumorigenicity of glioblastoma cells. We further show that SOX9 is upregulated in glioblastoma cells and directly enhances the expression of LGR5. We also demonstrate that knockdown of SOX9 suppresses the proliferation and tumorigenicity of glioblastoma cells. These results suggest that SOX9-mediated transcriptional regulation of LGR5 is critical for the tumorigenicity of glioblastoma cells. We speculate that the SOX9-LGR5 pathway could be a potentially promising target for the therapy of glioblastoma.


Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/metabolism , Receptors, G-Protein-Coupled/physiology , SOX9 Transcription Factor/physiology , Up-Regulation/physiology , Brain Neoplasms/pathology , Cell Line, Tumor , Gene Knockdown Techniques , Glioblastoma/pathology , Humans , Receptors, G-Protein-Coupled/genetics , SOX9 Transcription Factor/genetics
8.
Proc Natl Acad Sci U S A ; 109(47): 19426-31, 2012 Nov 20.
Article in English | MEDLINE | ID: mdl-23129617

ABSTRACT

AMPA receptors (AMPARs) mediate the majority of fast excitatory neurotransmission, and their density at postsynaptic sites determines synaptic strength. Ubiquitination is a posttranslational modification that dynamically regulates the synaptic expression of many proteins. However, very few of the ubiquitinating enzymes implicated in the process have been identified. In a screen to identify transmembrane RING domain-containing E3 ubiquitin ligases that regulate surface expression of AMPARs, we identified RNF167. Predominantly lysosomal, a subpopulation of RNF167 is located on the surface of cultured neurons. Using a RING mutant RNF167 or a specific shRNA to eliminate endogenous RNF167, we demonstrate that AMPAR surface expression increases in hippocampal neurons with disrupted RNF167 activity and that RNF167 is involved in activity-dependent ubiquitination of AMPARs. In addition, RNF167 regulates synaptic AMPAR currents, whereas synaptic NMDAR currents are unaffected. Therefore, our study identifies RNF167 as a selective regulator of AMPAR-mediated neurotransmission and expands our understanding of how ubiquitination dynamically regulates excitatory synapses.


Subject(s)
Receptors, AMPA/metabolism , Synaptic Transmission , Ubiquitin-Protein Ligases/metabolism , Animals , Cells, Cultured , Gene Expression Regulation , Gene Knockdown Techniques , HeLa Cells , Hippocampus/cytology , Humans , Lysosomes/metabolism , Neurons/metabolism , Protein Transport , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Ubiquitin-Protein Ligases/genetics , Ubiquitination
9.
Biochem Biophys Res Commun ; 444(1): 13-8, 2014 Jan 31.
Article in English | MEDLINE | ID: mdl-24406169

ABSTRACT

Protocadherin10 (PCDH10)/OL-protocadherin is a cadherin-related transmembrane protein that has multiple roles in the brain, including facilitating specific cell-cell connections, cell migration and axon guidance. It has recently been reported that PCDH10 functions as a tumor suppressor and that its overexpression inhibits proliferation or invasion of multiple tumor cells. However, the function of PCDH10 in glioblastoma cells has not been elucidated. In contrast to previous reports on other tumors, we show here that suppression of the expression of PCDH10 by RNA interference (RNAi) induces the growth arrest and apoptosis of glioblastoma cells in vitro. Furthermore, we demonstrate that knockdown of PCDH10 inhibits the growth of glioblastoma cells xenografted into immunocompromised mice. These results suggest that PCDH10 is required for the proliferation and tumorigenicity of glioblastoma cells. We speculate that PCDH10 may be a promising target for the therapy of glioblastoma.


Subject(s)
Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cadherins/metabolism , Glioblastoma/metabolism , Glioblastoma/pathology , Animals , Apoptosis , Brain Neoplasms/genetics , Cadherins/antagonists & inhibitors , Cadherins/genetics , Cell Line, Tumor , Cell Proliferation , Gene Knockdown Techniques , Glioblastoma/genetics , Heterografts , Humans , Mice , Mice, Nude , Neoplasm Invasiveness , Oncogene Proteins/antagonists & inhibitors , Oncogene Proteins/genetics , Oncogene Proteins/metabolism , Protocadherins , RNA Interference
10.
Gan To Kagaku Ryoho ; 41(7): 811-6, 2014 Jul.
Article in Japanese | MEDLINE | ID: mdl-25131865

ABSTRACT

Abiraterone acetate(AA)has been approved in more than 80 countries for the treatment of patients with metastatic castration-resistant prostate cancer(mCRPC). In July 2013, a marketing approval application for AA was submitted to the Japanese Ministry of Health, Labour, and Welfare. AA is a selective inhibitor of CYP17A1, a crucial enzyme for androgen biosynthesis. AA exerts its anti-tumor activity by directly inhibiting androgen production at all three sources, i. e., the testes, adrenal glands, and tumor itself. Data from international phase III studies and phase I and II studies in Japan have indicated that AA improves the overall survival and quality of life(QoL)of patients with mCRPC. Herein, we have summarized the development of AA and the results of important international and local clinical trials in Japan. In addition, the effect of food on AA bioavailability, concomitant steroid use, and liver function test abnormalities have been discussed regarding the appropriate use of AA.


Subject(s)
Androstadienes/therapeutic use , Androstenols/therapeutic use , Clinical Trials as Topic , Enzyme Inhibitors/therapeutic use , Prostatic Neoplasms, Castration-Resistant/drug therapy , Steroid 17-alpha-Hydroxylase/antagonists & inhibitors , Abiraterone Acetate , Androstadienes/adverse effects , Androstenes , Androstenols/adverse effects , Chemical and Drug Induced Liver Injury , Enzyme Inhibitors/adverse effects , Humans , Male , Prostatic Neoplasms, Castration-Resistant/enzymology
11.
Anticancer Res ; 44(10): 4261-4272, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39348980

ABSTRACT

BACKGROUND/AIM: Breast cancer is a heterogeneous disease with many subtypes, and the association between these subtypes and exposure to environmental factors such as radiation remains controversial. Although the rat is used widely for research into human breast cancer, the heterogeneity and subtype definitions are unclear. Here, we leveraged an archive of rat mammary cancer samples and gene expression microarray data to classify tumors and examine their association with exposures. MATERIALS AND METHODS: Eighty-four mammary cancer and 12 normal mammary tissue samples were obtained from previous experiments in which rats were exposed to different types of radiation, chemical carcinogens, and diets. Tumors were then subjected to immunohistochemical (IHC) analysis of conventional biomarkers, as well as gene expression profiling; they were then classified by three approaches based on IHC results, the PAM50 classifier algorithm, and unsupervised clustering of gene expression profiles. RESULTS: IHC identified four subtypes (luminal A-like, luminal B-like 1, luminal B-like 2, and triple-negative), while PAM50 identified six (luminal A, luminal B, basal-like, HER2-enriched, normal-like, and claudin-low). Unsupervised clustering divided the tumors into three large, statistically significant, groups (named "luminal A", "luminal B", and "non-luminal" clusters). The results of the three approaches were significantly associated with each other. Exposure to radiation and chemical carcinogens during post-pubertal development was significantly associated with an increased risk of developing luminal A tumors, whereas exposure to a high corn-oil diet was associated with a higher likelihood of luminal B tumors. CONCLUSION: Rat mammary cancer subtypes resemble those in humans and are related to environmental factors.


Subject(s)
Environmental Exposure , Animals , Female , Rats , Environmental Exposure/adverse effects , Gene Expression Profiling , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/genetics , Mammary Neoplasms, Experimental/pathology , Mammary Neoplasms, Experimental/genetics , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/etiology , Mammary Neoplasms, Animal/genetics , Mammary Neoplasms, Animal/pathology , Mammary Neoplasms, Animal/metabolism , Mammary Neoplasms, Animal/etiology , Gene Expression Regulation, Neoplastic
12.
J Radiat Res ; 65(5): 640-650, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39238338

ABSTRACT

Ionizing radiation promotes mammary carcinogenesis. Induction of DNA double-strand breaks (DSBs) is the initial event after radiation exposure, which can potentially lead to carcinogenesis, but the dynamics of DSB induction and repair are not well understood at the tissue level. In this study, we used female rats, which have been recognized as a useful experimental model for studying radiation effects on the mammary gland. We focused on differences in DSB kinetics among basal cells, luminal progenitor and mature cells in different parts of the mammary duct. 53BP1 foci were used as surrogate markers of DSBs, and 53BP1 foci in each mammary epithelial cell in immunostained tissue sections were counted 1-24 h after irradiation and fitted to an exponential function of time. Basal cells were identified as cytokeratin (CK) 14+ cells, luminal progenitor cells as CK8 + 18low cells and luminal mature cells as CK8 + 18high cells. The number of DSBs per nucleus tended to be higher in luminal cells than basal cells at 1 h post-irradiation. A model analysis indicated that basal cells in terminal end buds (TEBs), which constitute the leading edge of the mammary duct, had significantly fewer initial DSBs than the two types of luminal cells, and there was no significant difference in initial amount among the cell types in the subtending duct. The repair rate did not differ among mammary epithelial cell types or their locations. Thus, luminal progenitor and mature cells are more susceptible to radiation-induced DSBs than are basal cells in TEBs.


Subject(s)
DNA Breaks, Double-Stranded , Mammary Glands, Animal , Stem Cells , Animals , Female , DNA Breaks, Double-Stranded/radiation effects , Mammary Glands, Animal/radiation effects , Mammary Glands, Animal/cytology , Stem Cells/radiation effects , Stem Cells/cytology , Stem Cells/metabolism , Rats , Dose-Response Relationship, Radiation , Rats, Sprague-Dawley , Epithelial Cells/radiation effects , Epithelial Cells/metabolism , Epithelial Cells/cytology
13.
Nanoscale Horiz ; 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39297440

ABSTRACT

Quantum sensing using the fluorescent nanodiamond (FND) nitrogen-vacancy center enables physical/chemical measurements of the microenvironment, although application of such measurements in living mammals poses significant challenges due to the unknown biodistribution and toxicity of FNDs, the limited penetration of visible light for quantum state manipulation/measurement, and interference from physiological motion. Here, we describe a microenvironmental thermometry technique using FNDs in rat mammary epithelium, an important model for mammary gland biology and breast cancer research. FNDs were injected directly into the mammary gland. Microscopic observation of mammary tissue sections showed that most FNDs remained in the mammary epithelium for at least 8 weeks. Pathological examination indicated no obvious change in tissue morphology, suggesting negligible toxicity. Optical excitation and detection were performed through a skin incision. Periodic movements due to respiration and heartbeat were mitigated by frequency filtering of the signal. Based on these methods, we successfully detected temperature elevation in the mammary epithelium associated with lipopolysaccharide-induced inflammation, demonstrating the sensitivity and relevance of the technique in biological contexts. This study lays the groundwork for expanding the applicability of quantum sensing in biomedical research, providing a tool for real-time monitoring of physiological and pathological processes.

14.
Clin Pharmacol Drug Dev ; 12(1): 77-84, 2023 01.
Article in English | MEDLINE | ID: mdl-36225132

ABSTRACT

Intravenous edaravone is used to treat patients with amyotrophic lateral sclerosis. This randomized, open-label, two-way crossover, single-dose phase 1 study compared the relative bioavailability of a newly developed edaravone oral suspension when administered orally and via a nasogastric tube (NGT) as a model of percutaneous endoscopic gastrostomy tube administration in healthy adult subjects. Thirty-six subjects were randomly assigned to one of two groups, with 18 per group. Blood was collected pre- and post-dose for pharmacokinetic assessments; safety was evaluated. Plasma concentration-time profiles of unchanged edaravone were similar between administration routes. Comparative bioavailability analysis revealed that geometric least squares mean ratios (NGT/oral) for maximum plasma concentration and area under the plasma concentration-time curve from time zero to infinity of unchanged edaravone were 1.052 and 0.981, respectively. No serious adverse events or adverse drug reactions were reported. These results suggest that oral edaravone suspension can be administered directly to the stomach without dose adjustment via feeding tubes; both oral and NGT administration are well tolerated.


Subject(s)
Intubation, Gastrointestinal , Humans , Adult , Edaravone/adverse effects , Biological Availability , Administration, Oral
15.
Clin Ther ; 45(12): 1251-1258, 2023 12.
Article in English | MEDLINE | ID: mdl-37953075

ABSTRACT

PURPOSE: Edaravone is a neuroprotective agent approved as an intravenous treatment for amyotrophic lateral sclerosis (ALS). The intravenous administration of edaravone places a burden on patients and there is a clinical need for oral agents for the treatment of ALS. This report aimed to assess the pharmacokinetics and safety of an edaravone oral suspension in patients with ALS after oral and percutaneous endoscopic gastrostomy (PEG) tube administration. METHODS: Two single-dose, open-label phase 1 clinical studies were conducted. Edaravone oral suspension (105 mg of edaravone in 5 mL aqueous suspension) was administered orally and via PEG tube to 9 and 6 Japanese patients with ALS, respectively. Plasma and urinary pharmacokinetics of unchanged edaravone and its metabolites (sulfate and glucuronide conjugates) were determined. Safety was also evaluated. FINDINGS: After reaching maximum plasma concentration, the mean plasma concentration-time of unchanged edaravone showed a triphasic elimination. Mean plasma concentration-time profiles of the metabolites were higher than those of unchanged edaravone. The mean urinary excretion ratios were higher for the glucuronide conjugate than for either unchanged edaravone or the sulfate conjugate. In patients administered edaravone orally, a single adverse event occurred (blood urine present), which was mild and improved without medical intervention. No adverse drug reactions or serious adverse events were reported. In patients administered edaravone via PEG tube, 5 treatment-emergent adverse events were reported in 3 patients; none were related to the study drug. No adverse drug reactions were reported. IMPLICATIONS: In patients with ALS, a single dose of edaravone oral suspension was well absorbed and mainly eliminated in urine as the glucuronide conjugate. No safety concerns emerged. Pharmacokinetics were similar to those previously reported in healthy participants following oral administration. This indicates that effective drug concentrations were achieved and edaravone can be successfully administered both orally and via a PEG tube in patients with ALS. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT04176224 (oral administration) and NCT04254913 (PEG tube administration), www. CLINICALTRIALS: gov.


Subject(s)
Amyotrophic Lateral Sclerosis , Neuroprotective Agents , Humans , Amyotrophic Lateral Sclerosis/drug therapy , Edaravone/pharmacokinetics , Glucuronides/therapeutic use , Neuroprotective Agents/pharmacokinetics , Sulfates/therapeutic use
16.
J Neurosci ; 31(8): 3077-81, 2011 Feb 23.
Article in English | MEDLINE | ID: mdl-21414928

ABSTRACT

AMPA receptors (AMPARs) are postsynaptic glutamate-gated ion channels that mediate fast excitatory neurotransmission in the mammalian brain. Synaptic activity modulates the density of synaptic AMPARs, thereby affecting synaptic function, learning, and memory. Consequently, there is intense interest in defining the molecular mechanisms regulating AMPAR trafficking. Protein expression in the postsynaptic density of excitatory synapses is tightly regulated by ubiquitination, a posttranslational modification that dynamically regulates protein trafficking and degradation in response to synaptic activity. In this study, we demonstrate that increasing synaptic activity, via treatment with the GABA(A) receptor antagonist bicuculline, rapidly and robustly induces ubiquitination of the GluA2 AMPAR subunit. Similarly, treatment with AMPAR agonists results in GluA2 ubiquitination, which suggests that ligand binding plays a critical role. Finally, we find that clathrin- and dynamin-dependent endocytosis of AMPARs is required for activity-dependent GluA2 ubiquitination. Our finding that GluA2 undergoes activity-dependent ubiquitination expands our understanding of how ubiquitination regulates synaptic plasticity.


Subject(s)
Central Nervous System/metabolism , Neuronal Plasticity/physiology , Neurons/metabolism , Receptors, AMPA/physiology , Synaptic Transmission/physiology , Ubiquitination/physiology , Animals , Cells, Cultured , Central Nervous System/cytology , Neurons/cytology , Rats , Rats, Sprague-Dawley , Receptors, AMPA/agonists
17.
Acta Paediatr ; 101(8): 805-7, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22519914

ABSTRACT

UNLABELLED: There are more than 6000 rare diseases (defined as affecting <5/10 000 individuals in Europe, <200 000 people in the United States). The rarity can create problems including: difficulties in obtaining timely, accurate diagnoses; lack of experienced healthcare providers; useful, reliable and timely information may be hard to find; research activities are less common; developing new medicines may not be economically feasible; treatments are sometimes very expensive; and in developing countries, the problems are compounded by other resource limitations. Emphasis is required to support appropriate research and development leading to better prevention, diagnosis and treatments of rare diseases. Notably, clinical trials using already existing drugs may result in new, affordable, treatment strategies. Moreover, rare diseases may teach us about common disorders. CONCLUSIONS: Countries are encouraged to implement specific research and development activities within their individual capabilities, so that patients worldwide have equal access to necessary interventions to maximize the potential of every individual.


Subject(s)
Biomedical Research , Global Health , Health Policy , Health Services Accessibility , Rare Diseases , Biomedical Research/ethics , Biomedical Research/legislation & jurisprudence , Clinical Trials as Topic/ethics , Clinical Trials as Topic/legislation & jurisprudence , Health Policy/legislation & jurisprudence , Health Services Accessibility/ethics , Health Services Accessibility/legislation & jurisprudence , Humans , Orphan Drug Production/ethics , Orphan Drug Production/legislation & jurisprudence , Patient Advocacy , Patient Rights , Rare Diseases/diagnosis , Rare Diseases/therapy
18.
Anticancer Res ; 42(5): 2415-2423, 2022 May.
Article in English | MEDLINE | ID: mdl-35489722

ABSTRACT

BACKGROUND/AIM: Genetic and environmental factors interact to dictate the risk of cancer, and animal models are expected to provide avenues for identifying such interactions. The aim of the study was to clarify the genetic susceptibility of Copenhagen rats to spontaneous, radiation-induced, and chemically-induced mammary carcinogenesis. MATERIALS AND METHODS: Female Copenhagen and Sprague- Dawley rats and their F1 hybrids were subjected at age 7 weeks to γ-irradiation or intraperitoneal injection with 1-methyl-1-nitrosourea or were not treated, and palpable mammary tumours were diagnosed histologically. Data were pooled with previous data acquired for both nontreated and irradiated Sprague-Dawley rats. RESULTS: Radiation and 1-methyl-1-nitrosourea both significantly increased the incidence of mammary cancer in all strains. Copenhagen and F1 rats displayed a significantly lower incidence than Sprague-Dawley rats in all groups, with relatively higher incidence after irradiation. F1 rats exhibited significantly higher mammary cancer incidence than Copenhagen rats in the nontreated, but not the treated, groups. The interaction of the strain and exposure effects was suggested to be quasi-multiplicative. CONCLUSION: Copenhagen rats display non-uniform resistance to spontaneous, radiation-induced, and chemically-induced mammary carcinogenesis with dominant inheritance over Sprague-Dawley rats.


Subject(s)
Breast Neoplasms , Mammary Neoplasms, Experimental , Animals , Cell Transformation, Neoplastic , Female , Humans , Mammary Neoplasms, Experimental/chemically induced , Mammary Neoplasms, Experimental/genetics , Methylnitrosourea/toxicity , Rats , Rats, Sprague-Dawley
19.
Clin Ther ; 44(12): 1552-1565, 2022 12.
Article in English | MEDLINE | ID: mdl-36376130

ABSTRACT

PURPOSE: The safety and efficacy of intravenous edaravone, a neuroprotectant used for the treatment of amyotrophic lateral sclerosis (ALS), have been shown in clinical trials. An oral suspension of edaravone has been developed, but the food effect on its pharmacokinetic profile has not been evaluated. This study aimed to assess the food effect on the pharmacokinetic profile of edaravone after oral administration and to investigate dosing regimens and administration instructions with different meal intake and timing. METHODS: Data from 3 Phase I clinical studies were used to evaluate the effect of food on the pharmacokinetic profiles of a single dose of edaravone oral suspension. In all 3 studies, participants received a single dose of edaravone with various meal conditions. Healthy Japanese adult male participants (Studies 1, 2, and 3) or female participants (Study 3) aged 20 to 45 years at the time of informed consent were included. FINDINGS: In Study 1, 6 participants were enrolled and 5 completed the study. Nine and 16 participants were treated in Studies 2 and 3, respectively, and all completed the study. The Cmax and AUC0-∞ of edaravone were lower when administered 30 minutes after a high-fat meal compared with those in a fasted condition (Study 1). Lower plasma edaravone concentrations (approximately within the first hour) and subsequent lower Cmax and AUC0-∞ were observed after administration of edaravone 4 hours after a high-fat meal (Study 2) or 2 hours after a low-fat meal (Study 3). The Cmax and AUC0-∞ of oral edaravone were generally similar and not affected when administered 8 hours after a high-fat meal, 4 hours after a low-fat meal, or 2 hours after a light meal relative to the fasted condition. Administration of edaravone 1 hour before a high-fat meal resulted in no effect on Cmax or AUC0-∞ relative to the fasted condition. Administration of edaravone in the fed or fasted conditions resulted in a similar urine pharmacokinetic profile. IMPLICATIONS: Oral administration of edaravone with a meal decreased the plasma concentration of edaravone. Oral administration of edaravone 8 hours after a high-fat meal, 4 hours after a low-fat meal, 2 hours after a light meal, and 1 hour before a high-fat meal showed no effect of food on the PK profile of unchanged edaravone compared with that observed under a fasted condition. CLINICALTRIALS: gov identifiers: NCT04481750, NCT04481789, and NCT05342597.


Subject(s)
Fasting , Food-Drug Interactions , Adult , Female , Humans , Male , Administration, Oral , Area Under Curve , Biological Availability , Cross-Over Studies , Edaravone , Healthy Volunteers
20.
PLoS One ; 17(3): e0264228, 2022.
Article in English | MEDLINE | ID: mdl-35294462

ABSTRACT

Livestock manure and its management are significant sources of greenhouse gas (GHG). In most Southeast Asian countries, the current GHG emissions are estimated by the Intergovernmental Panel on Climate Change (IPCC) Tier 1 approach using default emission factors. Sun-drying is the dominant manure treatment in Vietnam, and in this study, we measured GHG emissions during manure drying using a chamber-based approach. Results show the emission factors for CH4 and N2O were 0.295 ± 0.078 g kg-1 volatile solids (VS) and 0.132 ± 0.136 g N2O-N kg-1 Ninitial, respectively. We monitored the total bacterial/archaeal community using 16S rRNA gene amplicon sequencing and measured the abundance of functional genes required for methanogenesis (mcrA), nitrification (amoA) and denitrification (nirK, nirS and nosZ) processes. Methane emission occurred only at the beginning of the drying process (days 1 to 3). The results of amplicon sequencing indicated that the relative abundance of methanogens also decreased during this period. Although some nitrification activity was detected, there was no significant N2O emission. These findings well describe the manure management system in south Vietnam and the GHG emission from this manure category, paving the way for higher Tier estimations using country-specific values.


Subject(s)
Greenhouse Gases , Microbiota , Animals , Cattle , Manure/analysis , Methane/analysis , Microbiota/genetics , Nitrous Oxide/analysis , RNA, Ribosomal, 16S/genetics , Vietnam
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