No abstract

COVID-19-associated deaths have been reported in the United States.* Reports of U.S. patients hospitalized with SARS-CoV-2 infection (the virus that causes COVID-19) describe high proportions of older, male, and black persons (2-4). Similarly, when comparing hospitalized patients with catchment area populations or nonhospitalized COVID-19 patients, high proportions have underlying conditions, including diabetes mellitus, hypertension, obesity, cardiovascular disease, chronic kidney disease, or chronic respiratory disease (3,4). For this report, data were abstracted from the medical records of 220 hospitalized and 311 nonhospitalized patients aged ≥18 years with laboratory-confirmed COVID-19 from six acute care hospitals and associated outpatient clinics in metropolitan Atlanta, Georgia. Multivariable analyses were performed to identify patient characteristics associated with hospitalization. The following characteristics were independently associated with hospitalization: age ≥65 years (adjusted odds ratio [aOR] = 3.4), black race (aOR = 3.2), having diabetes mellitus (aOR = 3.1), lack of insurance (aOR = 2.8), male sex (aOR = 2.4), smoking (aOR = 2.3), and obesity (aOR = 1.9). Infection with SARS-CoV-2 can lead to severe outcomes, including death, and measures to protect persons from infection, such as staying at home, social distancing (5), and awareness and management of underlying conditions should be emphasized for those at highest risk for hospitalization with COVID-19. Measures that prevent the spread of infection to others, such as wearing cloth face coverings (6), should be used whenever possible to protect groups at high risk. Potential barriers to the ability to adhere to these measures need to be addressed. Patients were selected from six acute care hospitals and associated outpatient clinics affiliated with a single academic health care system in metropolitan Atlanta. Hospitalized patients were selected sequentially from hospital-provided lists of * https://www.cdc.gov/coronavirus/2019-ncov/cases-in-us.html.

Hemangiomas are the most common type of tumor in infants. As they are endothelial cell-derived neoplasias, their growth can be regulated by the autocrine-acting Tie2 ligand angiopoietin 2 (Ang2). Using an experimental model of human hemangiomas, in which polyoma middle T-transformed brain endothelial (bEnd) cells are grafted subcutaneously into nude mice, we compared hemangioma growth originating from bEnd cells derived from wild-type, Ang2 +/-, and Ang2 -/-mice. Surprisingly, Ang2-deficient bEnd cells formed endothelial tumors that grew rapidly and were devoid of the typical cavernous architecture of slow-growing Ang2-expressing hemangiomas, while Ang2 +/-cells were greatly impaired in their in vivo growth. Gene array analysis identified a strong downregulation of NADPH oxidase 4 (Nox4) in Ang2 +/-cells. Correspondingly, lentiviral silencing of Nox4 in an Ang2-sufficient bEnd cell line decreased Ang2 mRNA levels and greatly impaired hemangioma growth in vivo. Using a structure-based approach, we identified fulvenes as what we believe to be a novel class of Nox inhibitors. We therefore produced and began the initial characterization of fulvenes as potential Nox inhibitors, finding that fulvene-5 efficiently inhibited Nox activity in vitro and potently inhibited hemangioma growth in vivo. In conclusion, the present study establishes Nox4 as a critical regulator of hemangioma growth and identifies fulvenes as a potential class of candidate inhibitor to therapeutically interfere with Nox function.

Background:Glucose regulated protein 78 (GRP78) functions as a sensor of endoplasmic reticulum (ER) stress. The aim of this study was to test the hypothesis that molecules that bind to GRP78 induce the unfolded protein response (UPR) and enhance cell death in combination with ER stress inducers.Methods:Differential scanning calorimetry (DSC), measurement of cell death by flow cytometry and the induction of ER stress markers using western blotting.Results:Epigallocatechin gallate (EGCG), a flavonoid component of Green Tea Camellia sinensis, and honokiol (HNK), a Magnolia grandiflora derivative, bind to unfolded conformations of the GRP78 ATPase domain. Epigallocatechin gallate and HNK induced death in six neuroectodermal tumour cell lines tested. Levels of death to HNK were twice that for EGCG; half-maximal effective doses were similar but EGCG sensitivity varied more widely between cell types. Honokiol induced ER stress and UPR as predicted from its ability to interact with GRP78, but EGCG was less effective. With respect to cell death, HNK had synergistic effects on melanoma and glioblastoma cells with the ER stress inducers fenretinide or bortezomib, but only additive (fenretinide) or inhibitory (bortezomib) effects on neuroblastoma cells.Conclusion:Honokiol induces apoptosis due to ER stress from an interaction with GRP78. The data are consistent with DSC results that suggest that HNK binds to GRP78 more effectively than EGCG. Therefore, HNK may warrant development as an antitumour drug.

Melanoma is a common malignancy which is poorly responsive to chemotherapy and radiation. One of the major reasons melanoma responds poorly to these modalities is constitutive expression of Akt, which protects against apoptosis. The antidepressant sertraline was found to be a potent cytotoxic agent against A375 human melanoma. To determine the mechanism by which sertraline kills melanoma cells, Western blot analysis of signaling molecules, including phosphorylated Akt, caspase 9 and phospho-p70 S6 kinase was performed. Finally, the effects of sertraline on A375 xenografts in mice were assessed. Sertaline potently inhibited the phosphorylation of Akt, and caused cell death through induction of endoplasmic reticulum in vitro. Sertraline monotherapy demonstrated activity against A375 xenografts in vivo. Akt is a major cause of resistance of melanoma to current therapy. Antidepressants are commonly used to prevent interferon-induced depression. Use of antidepressants that decrease Akt may improve the efficacy of interferon and other therapies against melanoma. Further studies are needed to elucidate whether sertraline acts as an Akt inhibitor in melanoma.

Alteration of mitochondrial structure and function is a hallmark of cancer cells different from normal cells and thus targeting mitochondria emerges as an novel approach for cancer therapy. Mitochondrial thioredoxin2 (Trx2) system is critical for cell viability, but the role in cancer biology is not well understood. Recently some cationic triphenylmethanes such as brilliant green (BG) and gentian violet showed antitumor and antiangiogenic activity by unknown mechanisms. Here we demonstrate that BG killed cells at nanomolar concentrations and targeted mitochondrial Trx2, which was oxidized and degraded. HeLa cells were more sensitive to BG than fibroblasts. In HeLa cells, Trx2 down-regulation by siRNA resulted in increased sensitivity to BG, whereas for fibroblasts, the same treatments had no effect. BG was visualized to accumulate in mitochondria and cause a rapid and dramatic decrease of mitochondrial Trx2 protein. With a redox Western blot method, we found that treatment with BG caused oxidation of both Trx1 and Trx2, followed by release of cytochrome c and apoptosis inducing factor from mitochondria into cytosol. Moreover, this treatment resulted in an elevation of mRNA level of Lon protease, a protein quality control enzyme in mitochondrial matrix, suggesting that the oxidized Trx2 may be degraded by Lon protease.

Tuberous sclerosis (TS) is a common autosomal dominant disorder caused by loss or malfunction of hamartin (tsc1) or tuberin (tsc2). Many lesions in TS do not demonstrate loss of heterozygosity for these genes, implying that dominant negative forms of these genes may account for some hamartomas and neoplasms in TS. To test this hypothesis, we expressed a dominant negative allele of tuberin (⌬RG) behind the cytomegalovirus promoter in NIH3T3 cells and transgenic mice. This allele binds hamartin but has a deletion in the C terminus of tuberin, leading to constitutive activation of rap1 and rab5/rabaptin. Expression of ⌬RG in NIH3T3 cells led to a strong induction of reactive oxygen species, induction of vascular endothelial growth factor, and malignant transformation in vivo. Expression of ⌬RG driven by the constitutive cytomegalovirus promoter led to high level expression in all murine tissues examined, including skin, kidney, liver, and brain. Surprisingly, mice expressing the ⌬RG transgene developed a fibrovascular collagenoma in the dermis, which closely resembles the Shagreen patch observed in human patients with TS. In addition, numerous small subpial collections of external granule cells in the cerebellum were observed, which may be the murine equivalent of subependymal giant cell astrocytomas or tubers commonly seen in TS patients. Thus, expression of a dominant negative tuberin in multiple tissues can lead to a tissue-specific phenotype resembling some of the findings in human TS. Our data are the first to demonstrate that specific signaling abnormalities underlie specific hamartomas in a model of a human genetic disorder.

A series of new bisphenol derivatives bearing allylic moieties were synthesized as potential analogs of honokiol and/or magnolol. Certain compounds exhibited specific anti-proliferation activity against SVR cells and moderate anti-HIV-1 activity in primary human lymphocytes. Compound 5h was the most potent compound and its anti-tumor activity was evaluated in vivo.In the fight against diseases and body disorders, plants extracts were exploited heavily by ancient civilizations. Thus, Chinese medicine has developed over a period of several thousand years many preparations which are used in the treatment of a wide variety of clinical diseases. It is only in the last century that efforts have been made to isolate and identify specific active chemicals from these "cocktails". Saiboku-to, a mixture of natural products that contains magnolia bark, has been historically used for clinical depression, anxiety as well for thrombotic stroke. The principal active components of the mixture appear to be the neolignans magnolol 1 and honokiol 2. 1 These two compounds demonstrated various biological properties including anti-oxidant and antidepressant activities. 2 Recent studies in our laboratory also indicate that honokiol induced apoptosis in tumor cells, 3,4 inhibits angiogenesis 5 and has weak in vitro anti-HIV-1 activity. 6 This combination of biological properties justifies further studies in order to increase the potency of these lead compounds and to understand their mechanism of action. Even though, until now, only few analogs have been reported in the literature, it appears that honokiol and magnolol's potent activities are attributed to the presence of hydroxyl and allylic groups on a biphenolic moiety. 7 Thus, to clarify a structure-activity relationship and to improve the potent activity of these two compounds, some simple allylated biphenol analogs and some "flexible" allylated biphenolic derivatives varying a linker between the two aromatic rings were prepared. Herein, we report the preparation of various compounds 5a-i and 10, their antiviral and anti-proliferatives activities in vitro and the in vivo activity of compound 5h.The syntheses of 5a-i were accomplished with phenolic O-allylation of compounds 3a-i followed by Claisen rearrangement. Therefore, biphenol derivatives 3a-i were treated with excess of allyl bromide in the presence of potassium carbonate to afford corresponding bis (allyloxy)-biphenyls 4a-i. The following Claisen rearrangement of 4a-i was then performed in dichloromethane using 1.5 eq. of a 1M solution of BCl 3 to give the desired 3,3'-bisallylbiphenol 5a-i (scheme 1).