Induction of Chromatin Damage and Distribution of Isochromatid Breaks in Human Fibroblast Cells Exposed to Heavy Ions

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Neuroprotective effect of a new DJ-1-binding compound against neurodegeneration in Parkinson's disease and stroke model rats

<p>Abstract</p> <p>Background</p> <p>Parkinson's disease (PD) and cerebral ischemia are chronic and acute neurodegenerative diseases, respectively, and onsets of these diseases are thought to be induced at least by oxidative stress. PD is caused by decreased dopamine levels in the substantia nigra and striatum, and cerebral ischemia occurs as a result of local reduction or arrest of blood supply. Although a precursor of dopamine and inhibitors of dopamine degradation have been used for PD therapy and an anti-oxidant have been used for cerebral ischemia therapy, cell death progresses during treatment. Reagents that prevent oxidative stress-induced cell death are therefore necessary for fundamental therapies for PD and cerebral ischemia. DJ-1, a causative gene product of a familial form of PD, PARK7, plays roles in transcriptional regulation and anti-oxidative stress, and loss of its function is thought to result in the onset of PD. Superfluous oxidation of cysteine at amino acid 106 (C106) of DJ-1 renders DJ-1 inactive, and such oxidized DJ-1 has been observed in patients with the sporadic form of PD.</p> <p>Results</p> <p>In this study, a compound, comp-23, that binds to DJ-1 was isolated by virtual screening. Comp-23 prevented oxidative stress-induced death of SH-SY5Y cells and primary neuronal cells of the ventral mesencephalon but not that of DJ-1-knockdown SH-SY5Y cells, indicating that the effect of the compound is specific to DJ-1. Comp-23 inhibited the production of reactive oxygen species (ROS) induced by oxidative stress and prevented excess oxidation of DJ-1. Furthermore, comp-23 prevented dopaminergic cell death in the substantia nigra and restored movement abnormality in 6-hydroxyldopamine-injected and rotenone-treated PD model rats and mice. Comp-23 also reduced infarct size of cerebral ischemia in rats that had been induced by middle cerebral artery occlusion. Protective activity of comp-23 seemed to be stronger than that of previously identified compound B.</p> <p>Conclusions</p> <p>The results indicate that comp-23 exerts a neuroprotective effect by reducing ROS-mediated neuronal injury, suggesting that comp-23 becomes a lead compound for PD and ischemic neurodegeneration therapies.</p

可溶性Flt-1産生低下は、心筋リモデリングおよび心不全増悪に寄与する

Soluble fms-like tyrosine kinase-1 (sFlt-1), an endogenous inhibitor of vascular endothelial growth factor and placental growth factor, is involved in the pathogenesis of cardiovascular disease. However, the significance of sFlt-1 in heart failure has not been fully elucidated. We found that sFlt-1 is decreased in renal failure and serves as a key molecule in atherosclerosis. In this study, we aimed to investigate the role of the decreased sFlt-1 production in heart failure, using sFlt-1 knockout mice. sFlt-1 knockout mice and wild-type mice were subjected to transverse aortic constriction and evaluated after 7 days. The sFlt-1 knockout mice had significantly higher mortality (52% versus 15%; P=0.0002) attributable to heart failure and showed greater cardiac hypertrophy (heart weight to body weight ratio, 8.95±0.45 mg/g in sFlt-1 knockout mice versus 6.60±0.32 mg/g in wild-type mice; P<0.0001) and cardiac dysfunction, which was accompanied by a significant increase in macrophage infiltration and cardiac fibrosis, than wild-type mice after transverse aortic constriction. An anti–placental growth factor–neutralizing antibody prevented pressure overload–induced cardiac hypertrophy, fibrosis, and cardiac dysfunction. Moreover, monocyte chemoattractant protein-1 expression was significantly increased in the hypertrophied hearts of sFlt-1 knockout mice compared with wild-type mice. Monocyte chemoattractant protein-1 inhibition with neutralizing antibody ameliorated maladaptive cardiac remodeling in sFlt-1 knockout mice after transverse aortic constriction. In conclusion, decreased sFlt-1 production plays a key role in the aggravation of cardiac hypertrophy and heart failure through upregulation of monocyte chemoattractant protein-1 expression in pressure-overloaded heart.博士（医学）・乙第1384号・平成28年11月24日© 2016 American Heart Association, Inc.The definitive version is available at " https://doi.org/10.1161/HYPERTENSIONAHA.116.07371

THYROID DYSFUNCTION FOLLOWING ALPHA-INTERFERON TREATMENT FOR CHRONIC HEPATITIS C

In order to evaluate the influnces of IFNα on thyroid function, thyroid-stimulating hormone (TSH), total thyroxine (T4), free T4, tri-iodothyronine (T3), and thyroxine-binding globulin were examined in IFNα-treated 351 patients with chronic hepatitis C before and during therapy. As therapy, either 3 million units (MU) of human lymphoblastoid IFNα or 9MU of recombinant IFNα2a was administrated daily for the initial two weeks followed by three times a week for 22 weeks. There were nine patients showing thyroid dysfunction during IFNα therapy. They consist of one relapse of Graves' disease, one relapse of Hashimoto thyroiditis, one development of apparent thyroid insufficiency from subclinical hypothyroidism, five cases with transient hyperthyroidism and one case with transient hypothyroidism. T4 and T3 levels in most patients who transiently developed thyroid dysfunction were normalized spontaneously after the discontinuation of IFNα. Thyroid-related autoantibodies were positive in 4 patients before IFNα therapy and newly developed in one patient during therapy. Attention should be paid first to the previous histories of autoimmune thyroid diseases and the existence of thyroid-related autoantibodies for the prediction of development of thyroid dysfunction during IFNα therapy. In addition, serial examinations of TSH, T3 and T4 should be also necessary for early detection of transient thyroid dysfunction during IFNα therapy

Evolutionary histories of breast cancer and related clones

乳がん発生の進化の歴史を解明 --ゲノム解析による発がんメカニズムの探索--. 京都大学プレスリリース. 2023-07-28.Tracking the ol' mutation trail: Unraveling the long history of breast cancer formation. 京都大学プレスリリース. 2023-08-31.Recent studies have documented frequent evolution of clones carrying common cancer mutations in apparently normal tissues, which are implicated in cancer development1, 2, 3. However, our knowledge is still missing with regard to what additional driver events take place in what order, before one or more of these clones in normal tissues ultimately evolve to cancer. Here, using phylogenetic analyses of multiple microdissected samples from both cancer and non-cancer lesions, we show unique evolutionary histories of breast cancers harbouring der(1;16), a common driver alteration found in roughly 20% of breast cancers. The approximate timing of early evolutionary events was estimated from the mutation rate measured in normal epithelial cells. In der(1;16)(+) cancers, the derivative chromosome was acquired from early puberty to late adolescence, followed by the emergence of a common ancestor by the patient’s early 30s, from which both cancer and non-cancer clones evolved. Replacing the pre-existing mammary epithelium in the following years, these clones occupied a large area within the premenopausal breast tissues by the time of cancer diagnosis. Evolution of multiple independent cancer founders from the non-cancer ancestors was common, contributing to intratumour heterogeneity. The number of driver events did not correlate with histology, suggesting the role of local microenvironments and/or epigenetic driver events. A similar evolutionary pattern was also observed in another case evolving from an AKT1-mutated founder. Taken together, our findings provide new insight into how breast cancer evolves

Sequential therapies after atezolizumab plus bevacizumab or lenvatinib first-line treatments in hepatocellular carcinoma patients

Introduction: The aim of this retrospective proof-of-concept study was to compare different second-line treatments for patients with hepatocellular carcinoma and progressive disease (PD) after first-line lenvatinib or atezolizumab plus bevacizumab.Materials and methods: A total of 1381 patients had PD at first-line therapy. 917 patients received lenvatinib as first-line treatment, and 464 patients atezolizumab plus bevacizumab as first-line.Results: 49.6% of PD patients received a second-line therapy without any statistical difference in overall survival (OS) between lenvatinib (20.6 months) and atezolizumab plus bev-acizumab first-line (15.7 months; p = 0.12; hazard ratio [HR] = 0.80). After lenvatinib first-line, there wasn't any statistical difference between second-line therapy subgroups (p = 0.27; sorafenib HR: 1; immunotherapy HR: 0.69; other therapies HR: 0.85). Patients who under-went trans-arterial chemo-embolization (TACE) had a significative longer OS than patients who received sorafenib (24.7 versus 15.8 months, p &lt; 0.01; HR = 0.64). After atezolizumab plus bevacizumab first-line, there was a statistical difference between second-line therapy subgroups (p &lt; 0.01; sorafenib HR: 1; lenvatinib HR: 0.50; cabozantinib HR: 1.29; other therapies HR: 0.54). Patients who received lenvatinib (17.0 months) and those who under-went TACE (15.9 months) had a significative longer OS than patients treated with sorafenib (14.2 months; respectively, p = 0.01; HR = 0.45, and p &lt; 0.05; HR = 0.46).Conclusion: Approximately half of patients receiving first-line lenvatinib or atezolizumab plus bevacizumab access second-line treatment. Our data suggest that in patients progressed to atezolizumab plus bevacizumab, the systemic therapy able to achieve the longest survival is lenvatinib, while in patients progressed to lenvatinib, the systemic therapy able to achieve the longest survival is immunotherapy