Targeting the NAD Salvage Synthesis Pathway as a Novel Therapeutic Strategy for Osteosarcomas with Low NAPRT Expression

For osteosarcoma (OS), the most common primary malignant bone tumor, overall survival has hardly improved over the last four decades. Especially for metastatic OS, novel therapeutic targets are urgently needed. A hallmark of cancer is aberrant metabolism, which justifies targeting metabolic pathways as a promising therapeutic strategy. One of these metabolic pathways, the NAD+ synthesis pathway, can be considered as a potential target for OS treatment. Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme in the classical salvage pathway for NAD+ synthesis, and NAMPT is overexpressed in OS. In this study, five OS cell lines were treated with the NAMPT inhibitor FK866, which was shown to decrease nuclei count in a 2D in vitro model without inducing caspase-driven apoptosis. The reduction in cell viability by FK866 was confirmed in a 3D model of OS cell lines (n = 3). Interestingly, only OS cells with low nicotinic acid phosphoribosyltransferase domain containing 1 (NAPRT1) RNA expression were sensitive to NAMPT inhibition. Using a publicly available (Therapeutically Applicable Research to Generate Effective Treatments (TARGET)) and a previously published dataset, it was shown that in OS cell lines and primary tumors, low NAPRT1 RNA expression correlated with NAPRT1 methylation around the transcription start site. These results suggest that targeting NAMPT in osteosarcoma could be considered as a novel therapeutic strategy, where low NAPRT expression can serve as a biomarker for the selection of eligible patients.

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Effects of Hypericum perforatum extract on oxaliplatin-induced neurotoxicity: in vitro evaluations

Zeitschrift für Naturforschung C ◽

10.1515/znc-2016-0194 ◽

2017 ◽

Vol 72 (5-6) ◽

pp. 219-226 ◽

Cited By ~ 8

Author(s):

Lorenzo Cinci ◽

Lorenzo Di Cesare Mannelli ◽

Anna Maidecchi ◽

Luisa Mattoli ◽

Carla Ghelardini

Keyword(s):

Therapeutic Strategy ◽

In Vitro Model ◽

Caspase 3 ◽

Hypericum Perforatum ◽

Common Side Effect ◽

Rat Astrocytes ◽

Vitro Model ◽

Ht 29 ◽

Novel Therapeutic

Abstract Hypericum perforatum L. has been used for centuries as a natural remedy for the treatment of many disorders. Neuropathic pain is a common side effect of oxaliplatin-based chemotherapy and often the cause of therapy discontinuation. Thanks to its anti-inflammatory and analgesic effects, the use of H. perforatum may be a novel therapeutic strategy for neuropathy. The aim of this paper was to evaluate the effect of H. perforatum hydrophilic extract on an in vitro model of oxaliplatin-induced neurotoxicity. The antioxidant potential of extract was first evaluated in cell-free models by the thiobarbituric acid-reactive substances assay and nitro blue tetrazolium oxidation test; the ability of H. perforatum extract to reduce oxaliplatin-induced caspase-3 activity in rat astrocytes and its potential interference with the cytotoxic effects of oxaliplatin in a colorectal cancer in vitro model (HT-29 cells) were also evaluated. The extract showed a significant antioxidant effect and was able to reduce caspase-3 activity in rat astrocytes. Of note, the extract alone exerted a cytotoxic effect in HT-29 cells and did not reduce the cytotoxicity of oxaliplatin in HT-29 cells. These data suggest that H. perforatum could be used as a novel therapeutic strategy for counteracting chemotherapy-induced neuropathy.

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Apohemoglobin-haptoglobin complex attenuates the pathobiology of circulating acellular hemoglobin and heme

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00136.2020 ◽

2020 ◽

Vol 318 (5) ◽

pp. H1296-H1307 ◽

Cited By ~ 2

Author(s):

Carlos J. Munoz ◽

Ivan S. Pires ◽

Jin Hyen Baek ◽

Paul W. Buehler ◽

Andre F. Palmer ◽

...

Keyword(s):

Therapeutic Strategy ◽

Capillary Density ◽

Microvascular Blood Flow ◽

Systemic Hypertension ◽

Proof Of Concept ◽

Heme Transfer ◽

Ligand Transfer ◽

Novel Therapeutic

This study highlights the apoHb-Hp complex as a novel therapeutic strategy to attenuate the adverse systemic and microvascular responses to intravascular Hb and heme exposure. In vitro and in vivo Hb exchange and heme transfer experiments demonstrated proof-of-concept Hb/heme ligand transfer to apoHb-Hp. The apoHb-Hp complex reverses Hb- and heme-induced systemic hypertension and microvascular vasoconstriction, preserves microvascular blood flow, and functional capillary density. In summary, the unique properties of the apoHb-Hp complex prevent adverse systemic and microvascular responses to Hb and heme-albumin exposure and introduce a novel therapeutic approach to facilitate simultaneous removal of extracellular Hb and heme.

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Bromodomain protein inhibition: a novel therapeutic strategy in rheumatic diseases

RMD Open ◽

10.1136/rmdopen-2018-000744 ◽

2018 ◽

Vol 4 (2) ◽

pp. e000744 ◽

Cited By ~ 17

Author(s):

Kerstin Klein

Keyword(s):

Animal Models ◽

Rheumatic Diseases ◽

Transcriptional Activation ◽

Therapeutic Strategy ◽

Cell Types ◽

Protein Inhibition ◽

Different Cell Types ◽

Novel Therapeutic

The reading of acetylation marks on histones by bromodomain (BRD) proteins is a key event in transcriptional activation. Small molecule inhibitors targeting bromodomain and extra-terminal (BET) proteins compete for binding to acetylated histones. They have strong anti-inflammatory properties and exhibit encouraging effects in different cell types in vitro and in animal models resembling rheumatic diseases in vivo. Furthermore, recent studies that focus on BRD proteins beyond BET family members are discussed.

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Adrenomedullin expression in a rat model of acute lung injury induced by hypoxia and LPS

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00314.2004 ◽

2005 ◽

Vol 288 (3) ◽

pp. L536-L545 ◽

Cited By ~ 19

Author(s):

Jackeline Agorreta ◽

Javier J. Zulueta ◽

Luis M. Montuenga ◽

Mercedes Garayoa

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Cell Lines ◽

Rat Model ◽

In Vitro Model ◽

Rat Lung ◽

Vitro Model

Adrenomedullin (ADM) is upregulated independently by hypoxia and LPS, two key factors in the pathogenesis of acute lung injury (ALI). This study evaluates the expression of ADM in ALI using experimental models combining both stimuli: an in vivo model of rats treated with LPS and acute normobaric hypoxia (9% O2) and an in vitro model of rat lung cell lines cultured with LPS and exposed to hypoxia (1% O2). ADM expression was analyzed by in situ hybridization, Northern blot, Western blot, and RIA analyses. In the rat lung, combination of hypoxia and LPS treatments overcomes ADM induction occurring after each treatment alone. With in situ techniques, the synergistic effect of both stimuli mainly correlates with ADM expression in inflammatory cells within blood vessels and, to a lesser extent, to cells in the lung parenchyma and bronchiolar epithelial cells. In the in vitro model, hypoxia and hypoxia + LPS treatments caused a similar strong induction of ADM expression and secretion in epithelial and endothelial cell lines. In alveolar macrophages, however, LPS-induced ADM expression and secretion were further increased by the concomitant exposure to hypoxia, thus paralleling the in vivo response. In conclusion, ADM expression is highly induced in a variety of key lung cell types in this rat model of ALI by combination of hypoxia and LPS, suggesting an essential role for this mediator in this syndrome.

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Stable Transfection of the BovineNRAMP1 Gene into Murine RAW264.7 Cells: Effect onBrucella abortus Survival

Infection and Immunity ◽

10.1128/iai.69.5.3110-3119.2001 ◽

2001 ◽

Vol 69 (5) ◽

pp. 3110-3119 ◽

Cited By ~ 62

Author(s):

Robert Barthel ◽

Jianwei Feng ◽

Jorge A. Piedrahita ◽

David N. McMurray ◽

Joe W. Templeton ◽

...

Keyword(s):

Cell Lines ◽

In Vitro Model ◽

Regulatory Control ◽

Natural Resistance ◽

Ifn Γ ◽

Flanking Region ◽

Vitro Model ◽

Raw264.7 Macrophage

ABSTRACT Genetically based natural resistance to brucellosis in cattle provides for novel strategies to control zoonotic diseases. BovineNRAMP1, the homologue of a murine gene (Bcg), has been identified as a major candidate for controlling the in vivo resistant phenotype. We developed an in vitro model for expression of resistance- and susceptibility-associated alleles of bovine NRAMP1 as stable transgenes under the regulatory control of the bovineNRAMP1 promoter in the murine RAW264.7 macrophage cell line (Bcg s ) to analyze the regulation of the NRAMP1 gene and its role in macrophage function. We demonstrated that the 5′-flanking region of bovineNRAMP1, despite the lack of TATA and CAAT boxes, has a functional promoter capable of driving the expression of a transgene in murine macrophages. A polymorphism within a microsatellite in the 3′ untranslated region critically affects the expression of bovineNRAMP1 and the control of in vitro replication ofBrucella abortus but not Salmonella enterica serovar Dublin. We did not observe any differences in the production of NO by resting or gamma interferon (IFN-γ)- and IFN-γ–lipopolysaccharide (LPS)-treated transfected cell lines, yet the resistant transfected cell lines produced significantly less NO than other cell lines, following stimulation with LPS at 24 and 48 h.

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Targeted inhibition of the WEE1 kinase as novel therapeutic strategy in neuroendocrine neoplasms

Endocrine Related Cancer ◽

10.1530/erc-20-0500 ◽

2021 ◽

Author(s):

Lena Weindl ◽

Imke Atreya ◽

Peter Dietrich ◽

Sabine Neubeck ◽

...

Keyword(s):

Tyrosine Kinase ◽

Cell Lines ◽

Therapeutic Strategy ◽

Cell Cycle Checkpoint ◽

Mitotic Catastrophe ◽

Neuroendocrine Neoplasms ◽

Dna Double Strand Breaks ◽

M Cell ◽

Underlying Mechanisms ◽

Novel Therapeutic

Neuroendocrine neoplasms (NENs) represent a rare and heterogeneous group of malignancies, sharing features of both neural and endocrine cells. NENs G3 appear as a highly aggressive subset with poor prognosis and limited therapeutic options. The small-molecule inhibitor of the WEE1 tyrosine kinase, adavosertib (AZD1775), has previously demonstrated potent anti-tumor effects on various types of cancer in preclinical and clinical studies. However, the role of adavosertib in NENs G3 had remained elusive. We evaluated the effects of adavosertib on pancreatic (BON-1, QGP-1) and bronchopulmonary (NCI-H720) neuroendocrine tumor cell lines applying 2-dimensional and 3-dimensional spheroid models. We newly demonstrated that adavosertib is sufficient to reduce cell viability and proliferation in neuroendocrine cell lines with features of high-grade NENs. As underlying mechanisms, we identified adavosertib-mediated DNA-double-strand breaks and a G2/M cell cycle checkpoint abrogation leading into mitotic catastrophe and cancer cell apoptosis. Silencing of WEE1 via siRNA transfection resulted in a phenotype similar to adavosertib treatment. Together, inhibition of the WEE1 tyrosine kinase applying adavosertib on NENs G3 outlines a promising novel therapeutic strategy.

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Inhibition of the Formation In Vitro of Putatively Carcinogenic Metabolites Derived from S. haematobium and O. viverrini by Combination of Drugs with Antioxidants

Molecules ◽

10.3390/molecules24213842 ◽

2019 ◽

Vol 24 (21) ◽

pp. 3842

Author(s):

Maria João Gouveia ◽

Verónica Nogueira ◽

Bruno Araújo ◽

Fátima Gärtner ◽

Nuno Vale

Keyword(s):

Dna Adducts ◽

Therapeutic Strategy ◽

Drug Repurposing ◽

Inhibitory Effect ◽

Current Treatment ◽

Combination Drugs ◽

Therapeutic Alternatives ◽

And Control ◽

Novel Therapeutic

Infections caused by Schistosoma haematobium and Opisthorchis viverrini are classified as carcinogenic. Although carcinogenesis might be a multifactorial process, it has been postulated that these helminth produce/excrete oxysterols and estrogen-like metabolites that might act as initiators of their infection-associated carcinogenesis. Current treatment and control of these infections rely on a single drug, praziquantel, that mainly targets the parasites and not the pathologies related to the infection including cancer. Thus, there is a need to search for novel therapeutic alternatives that might include combinations of drugs and drug repurposing. Based on these concepts, we propose a novel therapeutic strategy that combines drugs with molecule antioxidants. We evaluate the efficacy of a novel therapeutic strategy to prevent the formation of putative carcinogenic metabolites precursors and DNA adducts. Firstly, we used a methodology previously established to synthesize metabolites precursors and DNA adducts in the presence of CYP450. Then, we evaluated the inhibition of their formation induced by drugs and antioxidants alone or in combination. Drugs and resveratrol alone did not show a significant inhibitory effect while N-acetylcysteine inhibited the formation of most metabolite precursors and DNA adducts. Moreover, the combinations of classical drugs with antioxidants were more effective rather than compounds alone. This strategy might be a valuable tool to prevent the initiation of helminth infection-associated carcinogenesis.

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CBMT-47. MODULATION OF NAD PATHWAYS AS A THERAPEUTIC STRATEGY FOR TARGETING IDH MUTANT GLIOMA

Neuro-Oncology ◽

10.1093/neuonc/noz175.169 ◽

2019 ◽

Vol 21 (Supplement_6) ◽

pp. vi43-vi43

Author(s):

Julie Miller ◽

Hiroaki Nagashima ◽

Alexandria Fink ◽

Kensuke Tateishi ◽

Hiroaki Wakimoto ◽

...

Keyword(s):

Therapeutic Strategy ◽

Cancer Survival ◽

Mutant Cell ◽

Expression System ◽

Nicotinamide Phosphoribosyltransferase ◽

Sirt1 Expression ◽

Nad Synthesis ◽

High Doses ◽

Mutant Cells ◽

Nad Depletion

Abstract BACKGROUND IDH mutant tumors exhibit an altered metabolic state which may be exploited for use as a novel therapeutic approach. Our previous work has shown the IDH mutant cancer survival is dependent on the biosynthetic enzyme, nicotinamide phosphoribosyltransferase (NAMPT), for the production of nicotinamide adenine (NAD). Inhibition of NAMPT activity (NAMPTi) efficiently targets IDH mutant cells. NAD steady-state is also influenced by consumptive processes that utilize NAD as a coenzyme, including Sirtuin (SIRT) signaling. To avoid concerns surrounding NAMPT inhibitor toxicity at high doses, we sought to investigate whether modulation of SIRT activity can effectively target IDH mutant cells. METHODS IDH1 mutant cancer cells and patient-derived glioma lines were engineered for loss of SIRT gene expression using CRISPR/Cas9 gene editing or SIRT1 overexpression using a tetracycline-inducible expression system. The effect of silenced or enhanced SIRT1 activity was then assessed in IDH1 mutant cells alone or in combination with NAMPT inhibitors. RESULTS Loss of SIRT1 expression, but not other SIRT family members, confers resistance to NAMPT inhibition in IDH1 mutant cells. Consistent with the hypothesis that SIRT1 is a major consumer of NAD, we observed a significantly smaller decline in NAD when SIRT1 is deleted. In agreement with these findings, when SIRT1 activity is enhanced from baseline by tetracycline-mediated induction of SIRT1 expression, IDH mutant cell growth is slowed. Further, overexpression of SIRT1 leads to decreased cell viability and enhanced NAD depletion when induced in combination with NAMPTi. CONCLUSIONS IDH mutant tumors are vulnerable to NAD depletion. Our results show that this metabolic liability can be targeted by a combination of enhanced NAD consumption via SIRT1 activation and inhibition of NAD synthesis. Importantly, compounds to enhance SIRT1 activity are relatively non-toxic and in development for aging and neurologic disease, allowing potential for rapid translation to an IDH mutant-directed treatment.

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