Enhancing preclinical predictivity in I-O: what is going wrong between preclinical in vitro/in vivo and clinical settings?

Abstract Glioblastoma cells with the crucial stemness property of self-renewal constitute therapy-resistant reservoirs that seed tumor relapse. Effective targeting of these cells in clinical settings has been hampered by their relative quiescence, which invalidates the cell replication bias of most current treatments. Furthermore, although their dependence on specific chromatin and transcriptional states for the maintenance of stemness programs has been proposed as a vulnerability, these nuclear programs have been challenging to target pharmaceutically. Therefore the identification of targetable chromatin paradigms regulating self-renewal would represent a significant advancement for this incurable malignancy. Here we report a new role for the histone variant macroH2A2 in modulating a targetable epigenetic network of stemness in glioblastoma. By integrating transcriptomic, bulk and single-cell epigenomic datasets we generated from patient-derived models and surgical specimens, we show that macroH2A2 represses a transcriptional network of stemness through direct regulation of chromatin accessibility at enhancer elements. Functional assays in vitro and in vivo further showcase that macroH2A2 antagonizes self-renewal and stemness in glioblastoma preclinical models. In agreement with our experimental findings, high expression of macroH2A2 is a positive prognostic factor in clinical glioblastoma cohorts. Reasoning that increasing macroH2A2 levels could be an effective strategy to repress stemness programs and ameliorate patient outcome, we embarked on a screen to identify compounds that could elevate macroH2A2 levels. We report that an inhibitor of the chromatin remodeler Menin increases macroH2A2 levels, which in turn repress self-renewal. Additionally, we provide evidence that Menin inhibition induces viral mimicry programs and the demise of glioblastoma cells. Menin inhibition is being tested in clinical trials for blood malignancies (NCT04067336). Our preclinical work therefore reveals a novel and central role for macroH2A2 in an epigenetic network of stemness and suggests new clinical approaches for glioblastoma.

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o-Raffinose cross-linked hemoglobin improves the hemostatic defect associated with anemia and thrombocytopenia in rabbits

Blood ◽

10.1182/blood.v96.10.3630 ◽

2000 ◽

Vol 96 (10) ◽

pp. 3630-3636 ◽

Cited By ~ 20

Author(s):

David H. Lee ◽

Leslie Bardossy ◽

Nichole Peterson ◽

Morris A. Blajchman

Keyword(s):

Blood Loss ◽

Bleeding Time ◽

Platelet Reactivity ◽

Inhibitory Effect ◽

Clinical Settings ◽

No Donor ◽

Hemostatic Effect ◽

Circulating Levels

Abstract Several different preparations of cross-linked hemoglobin (CLHb) are being evaluated for their efficacy and safety as red cell substitutes in a variety of preclinical and clinical settings. Because CLHb is known to sequester nitric oxide (NO) and inhibit NO-mediated processes, we hypothesized that CLHb would have a hemostatic effect by enhancing platelet reactivity, inducing vasoconstriction, or both. Infusion of o-raffinose CLHb shortened the prolonged microvascular bleeding time and decreased blood loss from ear incisions in rabbits rendered anemic and thrombocytopenic. Moreover, this hemostatic effect persisted for at least 24 hours after infusion. Phenylephrine induced a degree of vasoconstriction similar to that induced by CLHb but did not shorten the bleeding time or decrease blood loss, suggesting that vasoconstriction alone cannot account for the hemostatic effect of CLHb. There was no evidence of CLHb-induced activation of coagulation in vivo, since infusion of CLHb did not increase circulating levels of thrombin-antithrombin complex. In vitro, CLHb abolished the inhibitory effect of the NO donor 3-morpholinosydnonimine on platelet aggregation and enhanced the aggregation of stimulated but not resting platelets. This potentiating effect was not attenuated by the addition of superoxide dismutase or catalase. To evaluate the potential arterial thrombogenicity of CLHb, a model of carotid artery thrombosis was developed in rabbits without thrombocytopenia or anemia. Compared with albumin infusion, CLHb infusion shortened the time to complete carotid occlusion. These data suggest that CLHb may shift the thromboregulatory balance toward clot formation, resulting in decreased bleeding in anemic and thrombocytopenic rabbits and possibly increasing arterial thrombogenicity in normal rabbits.

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Efficient Therapeutic Delivery by a Novel Cell-Penetrating Peptide Derived from Acinus

Cancers ◽

10.3390/cancers12071858 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1858

Author(s):

Justine Habault ◽

Claire Fraser ◽

Ewa Pasquereau-Kotula ◽

Maëlys Born-Bony ◽

Anne Marie-Cardine ◽

...

Keyword(s):

Ex Vivo ◽

Clinical Settings ◽

Aspartic Acid Residue ◽

Circulating Cells ◽

C Terminus ◽

Cell Penetrating ◽

Endocytosis Pathway ◽

Cancerous Cells

In this study, we have identified a novel cell-penetrating sequence, termed hAP10, from the C-terminus of the human protein Acinus. hAP10 was able to efficiently enter various normal and cancerous cells, likely through an endocytosis pathway, and to deliver an EGFP cargo to the cell interior. Cell penetration of a peptide, hAP10DR, derived from hAP10 by mutation of an aspartic acid residue to an arginine was dramatically increased. Interestingly, a peptide containing a portion of the heptad leucine repeat region domain of the survival protein AAC-11 (residues 377–399) fused to either hAP10 or hAP10DR was able to induce tumor cells, but not normal cells, death both ex vivo on Sézary patients’ circulating cells and to inhibit tumor growth in vivo in a sub-cutaneous xenograft mouse model for the Sézary syndrome. Combined, our results indicate that hAP10 and hAP10DR may represent promising vehicles for the in vitro or in vivo delivery of bioactive cargos, with potential use in clinical settings.

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Pharmacological Properties of Curcumin

Advanced Pharmacological Uses of Medicinal Plants and Natural Products - Advances in Medical Diagnosis, Treatment, and Care ◽

10.4018/978-1-7998-2094-9.ch012 ◽

2020 ◽

pp. 235-248

Author(s):

Anuradha Singh

Keyword(s):

Clinical Trial ◽

Natural Product ◽

Mechanisms Of Action ◽

Clinical Settings ◽

Pharmacological Properties ◽

Pharmacological Effects ◽

The Poor ◽

Cellular Factors

Curcumin, the polyphenol natural product, is a constituent of the traditional medicine known as turmeric. Extensive research over the last 50 years has indicated that this polyphenol displays potent pharmacological effects by targeting many critical cellular factors through a diverse array of mechanisms of action. However, there are some obstacles that prevent this wonder molecule to be effective in clinical settings and limit its use to topical applications only. Curcumin has recently been classified as both PAINS (panassay interference compounds) and an IMPS (invalid metabolic panaceas) candidate. Due to likely false activity of curcumin in vitro and in vivo has resulted unsuccessful clinical trial of curcumin against several disease. The chapter will review the essential medicinal chemistry of curcumin as well as envisage a compilation and discussion on the poor bioavailability of curcumin.

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Pharmacological inhibition of LSD1 triggers myeloid differentiation by targeting GSE1, a novel oncogene in AML

10.1101/2021.02.16.431315 ◽

2021 ◽

Author(s):

Luciano Nicosia ◽

Francesca Ludovica Boffo ◽

Elena Ceccacci ◽

Isabella Pallavicini ◽

Fabio Bedin ◽

...

Keyword(s):

Myeloid Differentiation ◽

Clinical Settings ◽

Complex Mechanism ◽

Strong Decrease ◽

Complete Understanding ◽

Promising Target ◽

Anti Cancer ◽

Protein Reduction

AbstractThe histone de-methylase LSD1 is over-expressed in haematological tumours and has emerged as a promising target for anti-cancer treatment, so that several LSD1 inhibitors are under development and testing, in pre-clinical and clinical settings. However, the complete understanding of their complex mechanism of action is still unreached. Here, we unravelled a novel mode of action of the LSD1 inhibitors MC2580 and DDP-38003, showing that they can induce differentiation of AML cells through the down-regulation of the chromatin protein GSE1. Analysis of the phenotypic effects of GSE1 depletion in NB4 cells showed a strong decrease of cell viability in vitro and of tumour growth in vivo. Mechanistically, we found that a set of genes associated with immune response and cytokine signalling pathways are up-regulated by LSD1 inhibitors through GSE1 protein reduction and that LSD1 and GSE1 co-localise at promoters of a subset of these genes at the basal state, enforcing their transcriptional silencing. Moreover, we show that LSD1 inhibitors lead to the reduced binding of GSE1 to these promoters, activating transcriptional programs that trigger myeloid differentiation. Our study offers new insights on GSE1 as a novel therapeutic target for AML.

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Repeated Neonatal Sevoflurane Induced Neurocognitive Impairment Through NF-κB-Mediated Pyroptosis

10.21203/rs.3.rs-404817/v1 ◽

2021 ◽

Author(s):

Jing Dai ◽

Xue Li ◽

Cai Wang ◽

Shuxin Gu ◽

Lei Dai ◽

...

Keyword(s):

Hippocampal Neurons ◽

Biochemical Analysis ◽

Neurological Diseases ◽

Neurocognitive Impairment ◽

Postnatal Period ◽

Neuronal Morphology ◽

Clinical Settings

Abstract Background: Exposure to general anesthesia (GA) during the postnatal period is associated with neuroinflammation and long-term neurocognitive impairment in preclinical and clinical settings. Pyroptosis, a novel type of programmed cell death that along with inflammation, plays an important role in the mechanism of diverse neurological diseases. Nevertheless, its role in GA-induced neuroinflammation and neurocognitive impairment in developing brain has not been investigated. Methods: Rats at postnatal day 6 or primary hippocampal neurons at 9 days in vitro, received 3% sevoflurane for 2 hours daily for three consecutive days. A pharmacological inhibitor of nuclear factor (NF)‑κB (BAY 11-7082) was administered to suppress NF-κB activation. Histological and biochemical analysis were performed to assess the pyroptosis and neuronal and synaptic damages both in vivo and in vitro. In addition, behavioral tests were performed to evaluate the neurocognitive ability in rats.Results: Repeated sevoflurane exposures activated NF-κB-mediated pyroptosis and neuroinflammation in the hippocampus of developing rats, caused damages in neuronal morphology and synaptic integrity, and induced neurocognitive impairment in rats. BAY 11-7082, the inhibitor of NF-κB, suppressed the activation of pyroptosis, attenuated the neuronal and synaptic damages, and ameliorated the neurocognitive impairment induced by repeated sevoflurane in the developing rats.Conclusions: These results demonstrated that repeated sevoflurane GA might induce neuroinflammation and cognitive impairment in developing rats via activation of NF-κB-mediated pyroptosis. Our findings characterize a novel role for pyroptosis as a potential therapeutic target in neuroinflammation to repeated neonatal GA.

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Therapeutic Effects of Inhibitor of ompA Expression against Carbapenem-Resistant Acinetobacter baumannii Strains

International Journal of Molecular Sciences ◽

10.3390/ijms222212257 ◽

2021 ◽

Vol 22 (22) ◽

pp. 12257

Author(s):

Seok-Hyeon Na ◽

Hyejin Jeon ◽

Man-Hwan Oh ◽

Yoo-Jeong Kim ◽

Mingi Chu ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Survival Rates ◽

Clinical Settings ◽

Therapeutic Effects ◽

Dependent Manner ◽

Bacteriostatic Activity ◽

Carbapenem Resistant ◽

Eskape Pathogens

The widespread of carbapenem-resistant Acinetobacter baumannii (CRAB) is of great concern in clinical settings worldwide. It is urgent to develop new therapeutic agents against this pathogen. This study aimed to evaluate the therapeutic potentials of compound 62520, which has been previously identified as an inhibitor of the ompA promoter activity of A. baumannii, against CRAB isolates, both in vitro and in vivo. Compound 62520 was found to inhibit the ompA expression and biofilm formation in A. baumannii ATCC 17978 at sub-inhibitory concentrations in a dose-dependent manner. These inhibitory properties were also observed in clinical CRAB isolates belonging to sequence type (ST) 191. Additionally, compound 62520 exhibited a bacteriostatic activity against clinical clonal complex (CC) 208 CRAB isolates, including ST191, and ESKAPE pathogens. This bacteriostatic activity was not different between STs of CRAB isolates. Bacterial clearance was observed in mice infected with bioimaging A. baumannii strain 24 h after treatment with compound 62520. Compound 62520 was shown to significantly increase the survival rates of both immunocompetent and neutropenic mice infected with A. baumannii ATCC 17978. This compound also increased the survival rates of mice infected with clinical CRAB isolate. These results suggest that compound 62520 is a promising scaffold to develop a novel therapeutic agent against CRAB infections.

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DNAzymes, Novel Therapeutic Agents in Cancer Therapy: A Review of Concepts to Applications

Journal of Nucleic Acids ◽

10.1155/2021/9365081 ◽

2021 ◽

Vol 2021 ◽

pp. 1-21

Author(s):

I. B. K. Thomas ◽

K. A. P. Gaminda ◽

C. D. Jayasinghe ◽

D. T. Abeysinghe ◽

R. Senthilnithy

Keyword(s):

Nucleic Acid ◽

Cancer Therapy ◽

Cancer Drug ◽

Clinical Settings ◽

Full Potential ◽

In Vivo Models ◽

Recent Advances ◽

Catalytic Dna

The past few decades have witnessed a rapid evolution in cancer drug research which is aimed at developing active biological interventions to regulate cancer-specific molecular targets. Nucleic acid-based therapeutics, including ribozymes, antisense oligonucleotides, small interference RNA (siRNA), aptamer, and DNAzymes, have emerged as promising candidates regulating cancer-specific genes at either the transcriptional or posttranscriptional level. Gene-specific catalytic DNA molecules, or DNAzymes, have shown promise as a therapeutic intervention against cancer in various in vitro and in vivo models, expediting towards clinical applications. DNAzymes are single-stranded catalytic DNA that has not been observed in nature, and they are synthesized through in vitro selection processes from a large pool of random DNA libraries. The intrinsic properties of DNAzymes like small molecular weight, higher stability, excellent programmability, diversity, and low cost have brought them to the forefront of the nucleic acid-based therapeutic arsenal available for cancers. In recent years, considerable efforts have been undertaken to assess a variety of DNAzymes against different cancers. However, their therapeutic application is constrained by the low delivery efficiency, cellular uptake, and target detection within the tumour microenvironment. Thus, there is a pursuit to identify efficient delivery methods in vivo before the full potential of DNAzymes in cancer therapy is realized. In this light, a review of the recent advances in the use of DNAzymes against cancers in preclinical and clinical settings is valuable to understand its potential as effective cancer therapy. We have thus sought to firstly provide a brief overview of construction and recent improvements in the design of DNAzymes. Secondly, this review stipulates the efficacy, safety, and tolerability of DNAzymes developed against major hallmarks of cancers tested in preclinical and clinical settings. Lastly, the recent advances in DNAzyme delivery systems along with the challenges and prospects for the clinical application of DNAzymes as cancer therapy are also discussed.

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2605. Mixed Subpopulation of Hemolytic and Non-Hemolytic Phenotype in Clinical Staphylococcus aureus Blood Isolates

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.2283 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S905-S906

Author(s):

Seongman Bae ◽

Eunbeen Cho ◽

Eunmi Yang ◽

Hyeonji Seo ◽

Eun Sil Kim ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Agar Plate ◽

Surface Protein ◽

Blood Agar Plate ◽

Clinical Settings ◽

Sheep Blood Agar Plate ◽

Single Colony ◽

Mixed Pattern

Abstract Background Agr is a key regulator that controls expression of secreted exoproteins and surface protein in Staphylococcus aureus. It has been reported that mixed status of two different phenotypes including agr functional and nonfunctional subpopulations can coexist in vitro and in vivo. However, data on the natural course and clinical implication of the mixed agr status is limited. We thus investigated the frequency and characteristics of the mixed agr in clinical settings. Methods We evaluated isogenic paired MRSA isolates collected from patients with persistent S. aureus bacteremia (SAB) between October 2010 and April 2016, and then prospectively performed surveillance for the presence of mixed agr function in MRSA isolates from patients with SAB between May 2016 and December 2017. The mixed agr status was evaluated by single colony evaluation on sheep blood agar plate containing RN4220 supernatant (β-hemolysin) (Figure 1). Cross-streaking with RN4220 and RNAIII measurement were performed to confirm the agr functionality of each of hemolytic and non-hemolytic colonies, separately. The expression levels of RNAIII, hla, and saeS/saeR were measured by real-time reverse transcription polymerase chain reaction. Results A total of 161 first blood isolates were collected during study period, and 6 isolates (4%) displayed mixed phenotype by single colony test. The mixed hemolytic pattern was observed in 5 out of 52 ST72 isolates (10%) and 1 out of 82 ST5 isolates (1%) (Figure 1). No difference was found in the genotypes between hemolytic and non-hemolytic colonies from each isolate. Of the 6 isolates, three lost mixed hemolytic features in the follow-up blood cultures (Table 1). One ST72 and one ST5 isolate showed agr mixed pattern determined by different RNAIII levels, but remaining four ST72 isolates had mixed hemolytic pattern due to different expression of hla correlated with saeS/saeR expression (Figure 2). Conclusion The mixture of agr function status among the clinical blood isolates of MRSA was rarely observed and isolates displaying heterogeneous hemolytic phenotype were largely due to differential expression of α-hemolysin. Further investigation is needed to unveil the clinical significance of mixture of different hemolytic phenotypes. Disclosures All authors: No reported disclosures.

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Effect of somatostatin on mesenteric vascular resistance in normal and portal hypertensive rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1992.262.2.g274 ◽

1992 ◽

Vol 262 (2) ◽

pp. G274-G277 ◽

Cited By ~ 3

Author(s):

C. C. Sieber ◽

P. G. Mosca ◽

R. J. Groszmann

Keyword(s):

Muscle Tone ◽

Clinical Settings ◽

Hypertensive Rats ◽

Resistance Vessels ◽

Vessel Resistance ◽

Vascular Smooth Muscle Tone ◽

Mesenteric Vascular Resistance ◽

Analogue Octreotide

Vasoactive effects of natural somatostatin (SRIF-14) and its analogue octreotide were studied in in vitro perfused superior mesenteric arterial beds of normal (Sham) and portal hypertensive (PVL) rats. Tested concentrations covered the whole range used in clinical settings (10(-10) to 10(-5) M for SRIF-14 and 10(-11) to 10(-6) M for octreotide, respectively). Vessel resistances only minimally changed to infusions of SRIF-14 (from 3.5 +/- 0.4 to 3.7 +/- 0.5 mmHg.ml-1.min and 3.8 +/- 0.3 to 3.9 +/- 0.4 mmHg.ml-1.min for PVL and Sham) and octreotide (from 3.3 +/- 0.2 to 3.4 +/- 0.4 mmHg.ml-1.min and 3.8 +/- 0.4 to 4.0 42- 0.4 mmHg.ml-1.min for PVL and Sham). The same was true for bolus injections. In contrast, norepinephrine induced significant increases in vessel resistance (up to 110.6 +/- 20.1 mmHg.ml-1.min). In conclusion, SRIF-14 and octreotide exert no direct effect on vascular smooth muscle tone in splanchnic resistance vessels of Sham and PVL rats. The vasoconstriction reported in vivo seems therefore probably mediated by the ability of these peptides to inhibit the secretion of vasodilatatory substances.

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