Genotoxic Stress Abrogates Renewal of Melanocyte Stem Cells by Triggering Their Differentiation

SummarySomatic stem cell depletion due to the accumulation of DNA damage has been implicated in the appearance of aging-related phenotypes. Hair graying, a typical sign of aging in mammals, is caused by the incomplete maintenance of melanocyte stem cells (MSCs) with age. Here, we report that irreparable DNA damage, as caused by ionizing radiation, abrogates renewal of MSCs in mice. Surprisingly, the DNA-damage response triggers MSC differentiation into mature melanocytes in the niche, rather than inducing their apoptosis or senescence. The resulting MSC depletion leads to irreversible hair graying. Furthermore, deficiency of Ataxia-telangiectasia mutated (ATM), a central transducer kinase of the DNA-damage response, sensitizes MSCs to ectopic differentiation, demonstrating that the kinase protects MSCs from their premature differentiation by functioning as a “stemness checkpoint” to maintain the stem cell quality and quantity

Bevacizumab increases the sensitivity of olaparib to homologous recombination-proficient ovarian cancer by suppressing CRY1 via PI3K/AKT pathway

PARP inhibitors have changed the management of advanced high-grade epithelial ovarian cancer (EOC), especially homologous recombinant (HR)-deficient advanced high-grade EOC. However, the effect of PARP inhibitors on HR-proficient (HRP) EOC is limited. Thus, new therapeutic strategy for HRP EOC is desired. In recent clinical study, the combination of PARP inhibitors with anti-angiogenic agents improved therapeutic efficacy, even in HRP cases. These data suggested that anti-angiogenic agents might potentiate the response to PARP inhibitors in EOC cells. Here, we demonstrated that anti-angiogenic agents, bevacizumab and cediranib, increased the sensitivity of olaparib in HRP EOC cells by suppressing HR activity. Most of the γ-H2AX foci were co-localized with RAD51 foci in control cells. However, most of the RAD51 were decreased in the bevacizumab-treated cells. RNA sequencing showed that bevacizumab decreased the expression of CRY1 under DNA damage stress. CRY1 is one of the transcriptional coregulators associated with circadian rhythm and has recently been reported to regulate the expression of genes required for HR in cancer cells. We found that the anti-angiogenic agents suppressed the increase of CRY1 expression by inhibiting VEGF/VEGFR/PI3K pathway. The suppression of CRY1 expression resulted in decrease of HR activity. In addition, CRY1 inhibition also sensitized EOC cells to olaparib. These data suggested that anti-angiogenic agents and CRY1 inhibitors will be the promising candidate in the combination therapy with PARP inhibitors in HR-proficient EOC

Safety and Efficacy of FIT039 for Verruca Vulgaris: A Placebo-Controlled, Phase I/II Randomized Controlled Trial

TRIAL DESIGN: Human papillomavirus infection causes verruca vulgaris. CDK9 inhibitor FIT039 inhibits DNA virus proliferation in animal models. We conducted a multicenter, single-blind, placebo-controlled, randomized phase I/II clinical trial evaluating the safety and efficacy of FIT039 against verruca vulgaris. METHODS: Target lesions were treated with liquid nitrogen once, and a FIT039 patch or placebo patch was applied for 14 days. The primary endpoint was lesion disappearance. The secondary endpoints were safety and changes in dimension, cross-sectional area, and the number of petechial lesions. RESULTS: A total of 24 participants were randomly allocated to the FIT039 (n = 13, median age, 54 years) and placebo (n = 11, median age, 62 years) groups. Verruca vulgaris did not disappear. FIT039 decreased the dimension to 76% of the initial value on day 29, followed by an increase to 98% on day 57. Placebo showed a monotonic increase to 107% on day 57. Changes in the cross-sectional area and petechiae number were comparable between the groups. CONCLUSIONS: No drug-related adverse reactions occurred. FIT039 efficacy was not determined in this study

食パンのライフサイクルCO_2排出量

The purpose of this research decided to make the trial calculation of the C02 emissions in production of bread. The C02 emissions of the energy reason of the bread manufacturing process in a factory and a home were surveyed. The heat source of domestic oven has an electric formula and a gas type. Moreover, the C02 emissions of the automatic bread-baking machine UHome Bakery" were measured. As a result, C02 emissions were large when bread was baked in a domestic steam microwave oven and gas oven. It is thought that this difference is based on the size of the volume in a warehouse of oven. The C02 emissions in a factory, and in the case of a home bakery, it turned out that there is no big difference

Genotoxic stress abrogates renewal of melanocyte stem cells by triggering their differentiation.

金沢大学医薬保健研究域　医学系Somatic stem cell depletion due to the accumulation of DNA damage has been implicated in the appearance of aging-related phenotypes. Hair graying, a typical sign of aging in mammals, is caused by the incomplete maintenance of melanocyte stem cells (MSCs) with age. Here, we report that irreparable DNA damage, as caused by ionizing radiation, abrogates renewal of MSCs in mice. Surprisingly, the DNA-damage response triggers MSC differentiation into mature melanocytes in the niche, rather than inducing their apoptosis or senescence. The resulting MSC depletion leads to irreversible hair graying. Furthermore, deficiency of Ataxia-telangiectasia mutated (ATM), a central transducer kinase of the DNA-damage response, sensitizes MSCs to ectopic differentiation, demonstrating that the kinase protects MSCs from their premature differentiation by functioning as a "stemness checkpoint" to maintain the stem cell quality and quantity. © 2009 Elsevier Inc. All rights reserved

Role of exosomes as a proinflammatory mediator in the development of EBV-associated lymphoma

Epstein-Barr virus (EBV) causes various diseases in the elderly, including B-cell lymphoma such as Hodgkin's lymphoma and diffuse large B-cell lymphoma. Here, we show that EBV acts in trans on noninfected macrophages in the tumor through exosome secretion and augments the development of lymphomas. In a humanized mouse model, the different formation of lymphoproliferative disease (LPD) between 2 EBV strains (Akata and B95-8) was evident. Furthermore, injection of Akata-derived exosomes affected LPD severity, possibly through the regulation of macrophage phenotype in vivo. Exosomes collected from Akata-lymphoblastoid cell lines reportedly contain EBV-derived noncoding RNAs such as BamHI fragment A rightward transcript (BART) micro-RNAs (miRNAs) and EBVencoded RNA.We focused on the exosome-mediated delivery of BART miRNAs. In vitro, BART miRNAs could induce the immune regulatory phenotype in macrophages characterized by the gene expressions of interleukin 10, tumor necrosis factor-a, and arginase 1, suggesting the immune regulatory role of BART miRNAs.The expression level of an EBV-encoded miRNA was strongly linked to the clinical outcomes in elderly patients with diffuse large B-cell lymphoma.These results implicate BART miRNAs as 1 of the factors regulating the severity of lymphoproliferative disease and as a diagnostic marker for EBV1 B-cell lymphoma. (Blood. 2018;131(23):2552-2567)

Conserved Charged Amino Acids within Sendai Virus C Protein Play Multiple Roles in the Evasion of Innate Immune Responses

One of the accessory proteins of Sendai virus (SeV), C, translated from an alternate reading frame of P/V mRNA has been shown to function at multiple stages of infection in cell cultures as well as in mice. C protein has been reported to counteract signal transduction by interferon (IFN), inhibit apoptosis induced by the infection, enhance the efficiency of budding of viral particles, and regulate the polarity of viral genome-length RNA synthesis to maximize production of infectious particles. In this study, we have generated a series of SeV recombinants containing substitutions of highly conserved, charged residues within the C protein, and characterized them together with previously-reported C′/C(−), 4C(−), and F170S recombinant viruses in infected cell cultures in terms of viral replication, cytopathogenicity, and antagonizing effects on host innate immunity. Unexpectedly, the amino acid substitutions had no or minimal effect on viral growth and viral RNA synthesis. However, all the substitutions of charged amino acids resulted in the loss of a counteracting effect against the establishment of an IFN-α-mediated anti-viral state. Infection by the virus (Cm2′) containing mutations at K77 and D80 induced significant IFN-β production, severe cytopathic effects, and detectable amounts of viral dsRNA production. In addition to the Cm2′ virus, the virus containing mutations at E114 and E115 did not inhibit the poly(I:C)-triggered translocation of cellular IRF-3 to the nucleus. These results suggest that the C protein play important roles in viral escape from induction of IFN-β and cell death triggered by infection by means of counteracting the pathway leading to activation of IRF-3 as well as of minimizing viral dsRNA production

掌蹠の汗腺内における色素幹細胞とメラノーマ前駆細胞の同定

The final publication is available at http://dx.doi.org/10.1111/pcmr.12297. Natsuko Okamoto et al. A melanocyte–melanoma precursor niche in sweat glands of volar skin. Pigment Cell & Melanoma Research. Volume 27, Issue 6, pages 1039–1050, November 2014京都大学0048新制・論文博士博士(医学)乙第12890号論医博第2090号新制||医||1007(附属図書館)31644京都大学大学院医学研究科医学専攻(主査)教授 野田 亮, 教授 羽賀 博典, 教授 鈴木 茂彦学位規則第4条第2項該当Doctor of Medical ScienceKyoto UniversityDFA