scholarly journals Repurposing melanoma chemotherapy to activate inflammasomes in treatment of BRAF/MAPK inhibitor resistant melanoma

2021 ◽  
Author(s):  
Farzana Ahmed ◽  
Hsin-Yi Tseng ◽  
Antonio Ahn ◽  
Dilini Gunatilake ◽  
Sara Alavi ◽  
...  
Keyword(s):  
Mapk Pathway ◽  
Nsg Mice ◽  
Development Of Resistance ◽  
Undifferentiated State ◽  
Selective Targeting ◽  
Before And After ◽  
Inflammatory State ◽  
Mapk Inhibitor

AbstractThe development of resistance to treatments of melanoma is commonly associated with upregulation of the MAPK pathway and development of an undifferentiated state. Prior studies have suggested that melanoma with these resistance characteristics may be susceptible to innate death mechanisms such as pyroptosis triggered by activation of inflammasomes. In the present studies we have taken cell lines from patients before and after development of resistance to BRAF V600 inhibitors and exposed the resistant melanoma to temozolomide (a commonly used chemotherapy) with and without chloroquine to inhibit autophagy. It was found that melanoma with an inflammatory undifferentiated state appeared susceptible to this combination when tested in vitro and in vivo against xenografts in NSG mice. Translation of the latter results into patients would promise durable responses in patients treated by the combination. The inflammasome and death mechanism involved appeared to vary between melanoma and involved either AIM2, NLRP3 or NLRC4 inflammasomes and gasdermin D or E. These preliminary studies have raised questions as to the selectivity for different inflammasomes in different melanoma and their selective targeting by chemotherapy. They also question whether the inflammatory state of melanoma may be used as biomarkers to select patients for inflammasome targeted therapy.

scholarly journals Targeting Rad51 as a strategy for the treatment of melanoma cells resistant to MAPK pathway inhibition

2020 ◽  
Vol 11 (7) ◽  
Author(s):  
Elena Makino ◽  
Lisa Marie Fröhlich ◽  
Tobias Sinnberg ◽  
Corinna Kosnopfel ◽  
Birgit Sauer ◽  
...  
Keyword(s):  
Homologous Recombination ◽  
Metastatic Melanoma ◽  
Mapk Pathway ◽  
Critical Role ◽  
Melanoma Cells ◽  
Mapk Signaling ◽  
Transcriptional Level ◽  
Mapk Inhibitor

Abstract Rad51 is an essential factor of the homologous recombination DNA repair pathway and therefore plays an important role in maintaining genomic stability. We show that RAD51 and other homologous recombination repair genes are overexpressed in metastatic melanoma cell lines and in melanoma patient samples, which correlates with reduced survival of melanoma patients. In addition, Rad51 expression in melanoma cells was regulated on a transcriptional level by the MAPK signaling pathway with Elk1 as the main downstream transcriptional effector. Most strikingly, melanoma cells which developed resistance towards MAPK inhibitors could be efficiently targeted by Rad51 inhibitors similar to their sensitive counterparts, leading to DNA damage, G2/M arrest and apoptosis. Furthermore, the treatment of MAPK inhibitor resistant cells with Rad51 inhibitors enhances the susceptibility of these cells for MAPK inhibitor treatment in vitro and in vivo. These data indicate that Rad51 plays a critical role in the survival of metastatic melanoma cells and is a promising target for the therapy of melanoma irrespective of its MAPK inhibitor resistance status.

KD7150, a Novel Mercaptoketone-Based HDAC Inhibitor, Exerts Potent Anti-Multiple Myeloma Effects In Vitro and In Vivo by Induction of DNA Damage and Mitochondrial Signaling.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2519-2519
Author(s):  
Rentian Feng ◽  
Huihui Ma ◽  
Christian A. Hassig ◽  
Joseph E. Payne ◽  
Nicholas D. Smith ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Dna Damage ◽  
Hdac Inhibitor ◽  
Mapk Pathway ◽  
Heme Oxygenase 1 ◽  
Mitochondrial Signaling ◽  
Induction Of Apoptosis ◽  
Mapk Inhibitor

Abstract Histone deacetylase (HDAC) inhibitors have emerged as a class of novel and promising anti-cancer agents and their activities are currently being investigated in both the pre-clinical and clinical settings. Using an unbiased, ultrahigh throughput screening system a novel mercaptoketone-based HDAC inhibitor KD5170 was identified. This novel non-hydroxamic acid non-benzamide compound was profiled for its anti-myeloma activity in vitro and in vivo. KD5170 inhibited the proliferation of multiple myeloma (MM) cell lines and the viability of CD138+ primary MM cells by induction of apoptosis. This was accompanied by an increase of acetylation of histones and activation of caspase-3, -8 and -9. Treatment with KD5170 caused a loss of mitochondrial membrane potential measured by JC-1 staining and resulted in release of apoptogenic factors such as cytochrome c, smac, and AIF from mitochondria. Furthermore, KD5170 induced oxidative stress and oxidative DNA damage in myeloma cells, as evidenced by the upregulation of heme oxygenase-1 and H2A.X phosphorylation, respectively. Combination of KD5170 with the proteasome inhibitor bortezomib or TNF-related apoptosis-inducing ligand synergistically enhanced the anti-myeloma activity. Resistance of MM cells to KD5170 was associated with activation of the ERK/MAPK pathway under treatment with KD5170. Pretreatment with the MAPK-inhibitor restored the sensitivity to KD5170, suggesting that the combination of KD5170 with a MAPK inhibitor (U0126) could overcome drug resistance. Growth of myeloma tumor xenografts in KD5170-treated nude mice was significantly inhibited (1401 mm3 ± 596 versus 442 mm3 ± 221; P = .009) and survival was prolonged (9 days and 17.5 days; P= .0095) compared to vehicle-treated mice. Accordingly, our in vivo data showed that histone acetylation was markedly upregulated in tela in spleen or tumor tissues of the animals treated with KD5170 as early as 2 hours. In conclusion, our data show that KD5170 has anti-myeloma activity in vitro and in vivo, mediated by the induction of apoptosis due to DNA damage and mitochondrial signaling.

scholarly journals Mineralocorticoid Receptor Blockade Improves Insulin Sensitivity in the Rat Heart and a Possible Molecular Mechanism

2016 ◽  
Vol 39 (3) ◽  
pp. 860-870 ◽  
Author(s):  
Mei Wang ◽  
Yongjun Li ◽  
Kun Zhou ◽  
Guoru Zhang ◽  
Yaling Wang ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
P38 Mapk ◽  
Mineralocorticoid Receptor ◽  
Mapk Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Mapk Inhibitor

Background/Aims: Extensive research has explored the role of aldosterone in insulin resistance. Recent evidence suggests that the mineralocorticoid receptor (MR) mediates aldosterone-induced dysregulation of cytokines, and most of this research has focused on adjustments in fat tissue and adipocytes. However, the direct effect of MR blockade on insulin resistance in cardiomyocytes remains largely unknown. In the present study, we investigated whether MR blockade improves insulin-sensitizing factors in insulin-resistant rats and attenuates the dysregulation of the aldosterone-related transport of adiponectin and glucose in cardiomyocytes and examined the underlying mechanisms. Methods: The effects of aldosterone, MR inhibitors (e.g., eplerenone), a peroxisome proliferator-activated receptor (PPAR) α agonist, and a p38 mitogen-activated protein kinase (MAPK) inhibitor on adiponectin and glucose transport were studied at the mRNA and protein levels in vitro and in vivo. Results: Our data revealed that aldosterone reduced the expression of adiponectin and inhibited the transport of glucose in cardiomyocytes and that MR blockade reversed these affects. In vivo, MR blockade improved insulin-sensitive parameters and increased adiponectin expression in the myocardia of high-fat diet rats. Furthermore, aldosterone promoted p38MAPK expression but negatively affected PPARα expression, and the downregulation of adiponectin by aldosterone was reversed by MR blockade, a PPARα agonist, and a p38 MAPK inhibitor. Conclusion: The above results suggested that aldosterone promoted insulin resistance in the heart and that this effect could be partly reversed by MR blockade through signal transduction in the P38 MAPK pathway and PPARα.

Radiolabeled r-Hirudin as a Measure of Thrombin Activity at, or within, the Rabbit Aorta Wall In Vitro and In Vivo

1994 ◽  
Vol 71 (04) ◽  
pp. 499-506 ◽  
Author(s):  
Mark W C Hatton ◽  
Bonnie Ross-Ouellet
Keyword(s):  
Rabbit Aorta ◽  
Balloon Injury ◽  
Recombinant Hirudin ◽  
Aorta Wall ◽  
Thrombin Activity ◽  
Before And After ◽  
The Matrix

SummaryThe behavior of 125I-labeled recombinant hirudin towards the uninjured and de-endothelialized rabbit aorta wall has been studied in vitro and in vivo to determine its usefulness as an indicator of thrombin activity associated with the aorta wall. Thrombin adsorbed to either sulfopropyl-Sephadex or heparin-Sepharose bound >95% of 125I-r-hirudin and the complex remained bound to the matrix. Binding of 125I-r-hirudin to the exposed aorta subendothelium (intima-media) in vitro was increased substantially if the tissue was pre-treated with thrombin; the quantity of l25I-r-hirudin bound to the de-endothelialized intima-media (i.e. balloon-injured in vitro) correlated positively with the quantity of bound 131I-thrombin (p <0.01). Aortas balloon-injured in vivo were measured for thrombin release from, and binding of 125I-r-hirudin to, the de-endothelialized intimal surface in vitro; 125I-r-hirudin binding correlated with the amount of active thrombin released (p <0.001). Uptake of 125I-r-hirudin by the aorta wall in vivo was proportional to the uptake of 131I-fibrinogen (as an indicator of thrombin activity) before and after balloon injury. After 30 min in the circulation, specific 125I-r-hirudin binding to the uninjured and de-endo- thelialized (at 1.5 h after injury) aorta wall was equivalent to 3.4 (± 2.5) and 25.6 (±18.1) fmol of thrombin/cm2 of intima-media, respectively. Possibly, only hirudin-accessible, glycosaminoglycan-bound thrombin is measured in this way.

scholarly journals miR-146a-5p Promotes Chondrocyte Apoptosis and Inhibits Autophagy of Osteoarthritis by Targeting NUMB

Cartilage ◽  
2021 ◽  
pp. 194760352110235
Author(s):  
Hongjun Zhang ◽  
Wendi Zheng ◽  
Du Li ◽  
Jia Zheng
Keyword(s):  
Caspase 3 ◽  
Cartilage Tissue ◽  
Luciferase Reporter ◽  
Chondrocyte Apoptosis ◽  
Knee Cartilage ◽  
Before And After ◽  
Related Proteins ◽  
Human And Mouse

Objective miR-146a-5p was found to be significantly upregulated in cartilage tissue of patients with osteoarthritis (OA). NUMB was shown to be involved in the autophagy regulation process of cells. We aimed to learn whether NUMB was involved in the apoptosis or autophagy process of chondrocytes in OA and related with miR-146a-5p. Methods QRT-PCR was used to detect miR-146a-5p level in 22 OA cartilage tissues and 22 controls. The targets of miR-146a-5p were analyzed using software and the luciferase reporter experiment. The apoptosis and autophagy, and related proteins were detected in chondrocytes treated with miR-146a-5p mimic/inhibitor or pcDNA3.1-NUMB/si-NUMB and IL-1β, respectively. In vivo experiment, intra-articular injection of miR-146a-5p antagomir/NC was administered at the knee of OA male mice before and after model construction. Chondrocyte apoptosis and the expression of apoptosis and autophagy-related proteins were also detected. Results miR-146a-5p was highly expressed in knee cartilage tissue of patients with OA, while NUMB was lowly expressed and negatively regulated by miR-146a-5p. Upregulation of miR-146a-5p can promote cell apoptosis and reduce autophagy of human and mouse chondrocytes by modulating the levels of cleaved caspase-3, cleaved PARP, Bax, Beclin 1, ATG5, p62, LC3-I, and LC3-II. Increasing the low level of NUMB reversed the effects of miR-146a-5p on chondrocyte apoptosis and autophagy. Intra-articular injection of miR-146a-5p antagomir can also reverse the effects of miR-146a-5p on the apoptosis and autophagy of knee joint chondrocytes in OA mice. Conclusion Downregulation of miR-146a-5p suppresses the apoptosis and promotes autophagy of chondrocytes by targeting NUMB in vivo and in vitro.

scholarly journals Using the Microwell-mesh to culture microtissues in vitro and as a carrier to implant microtissues in vivo into mice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Melissa E. Monterosso ◽  
Kathryn Futrega ◽  
William B. Lott ◽  
Ian Vela ◽  
Elizabeth D. Williams ◽  
...  
Keyword(s):  
Hair Follicles ◽  
Live Animal ◽  
Nsg Mice ◽  
Animal Imaging ◽  
Organ Specific ◽  
Bioluminescence Signal ◽  
Serial Transplantation ◽  
Live Animal Imaging

AbstractProstate cancer (PCa) patient-derived xenografts (PDXs) are commonly propagated by serial transplantation of “pieces” of tumour in mice, but the cellular composition of pieces is not standardised. Herein, we optimised a microwell platform, the Microwell-mesh, to aggregate precise numbers of cells into arrays of microtissues, and then implanted the Microwell-mesh into NOD-scid IL2γ−/− (NSG) mice to study microtissue growth. First, mesh pore size was optimised using microtissues assembled from bone marrow-derived stromal cells, with mesh opening dimensions of 100×100 μm achieving superior microtissue vascularisation relative to mesh with 36×36 μm mesh openings. The optimised Microwell-mesh was used to assemble and implant PCa cell microtissue arrays (hereafter microtissues formed from cancer cells are referred to as microtumours) into mice. PCa cells were enriched from three different PDX lines, LuCaP35, LuCaP141, and BM18. 3D microtumours showed greater in vitro viability than 2D cultures, but neither proliferated. Microtumours were successfully established in mice 81% (57 of 70), 67% (4 of 6), 76% (19 of 25) for LuCaP35, LuCaP141, and BM18 PCa cells, respectively. Microtumour growth was tracked using live animal imaging for size or bioluminescence signal. If augmented with further imaging advances and cell bar coding, this microtumour model could enable greater resolution of PCa PDX drug response, and lead to the more efficient use of animals. The concept of microtissue assembly in the Microwell-mesh, and implantation in vivo may also have utility in implantation of islets, hair follicles or other organ-specific cells that self-assemble into 3D structures, providing an important bridge between in vitro assembly of mini-organs and in vivo implantation.

scholarly journals Sesquiterpene Lactones: Promising Natural Compounds to Fight Inflammation

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 991
Author(s):  
Melanie S. Matos ◽  
José D. Anastácio ◽  
Cláudia Nunes dos Santos
Keyword(s):  
Biological Activities ◽  
Sesquiterpene Lactones ◽  
Physiological State ◽  
Plant Secondary Metabolites ◽  
Inflammatory Pathways ◽  
Inflammatory State ◽  
Anti Inflammatory ◽  
Inflammatory Molecules

Inflammation is a crucial and complex process that reestablishes the physiological state after a noxious stimulus. In pathological conditions the inflammatory state may persist, leading to chronic inflammation and causing tissue damage. Sesquiterpene lactones (SLs) are composed of a large and diverse group of highly bioactive plant secondary metabolites, characterized by a 15-carbon backbone structure. In recent years, the interest in SLs has risen due to their vast array of biological activities beneficial for human health. The anti-inflammatory potential of these compounds results from their ability to target and inhibit various key pro-inflammatory molecules enrolled in diverse inflammatory pathways, and prevent or reduce the inflammatory damage on tissues. Research on the anti-inflammatory mechanisms of SLs has thrived over the last years, and numerous compounds from diverse plants have been studied, using in silico, in vitro, and in vivo assays. Besides their anti-inflammatory potential, their cytotoxicity, structure–activity relationships, and pharmacokinetics have been investigated. This review aims to gather the most relevant results and insights concerning the anti-inflammatory potential of SL-rich extracts and pure SLs, focusing on their effects in different inflammatory pathways and on different molecular players.

scholarly journals DDRE-07. DIPG HARBOUR ALTERATIONS TARGETABLE BY MEK INHIBITORS, WITH ACQUIRED RESISTANCE MECHANISMS OVERCOME BY COMBINATORIAL INHIBITION

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii62-ii62
Author(s):  
Elisa Izquierdo ◽  
Diana Carvalho ◽  
Alan Mackay ◽  
Sara Temelso ◽  
Jessica K R Boult ◽  
...  
Keyword(s):  
Drug Exposure ◽  
Mapk Pathway ◽  
Synergistic Effects ◽  
Acquired Resistance ◽  
Mek Inhibitor ◽  
Resistance Mechanisms ◽  
Genetic Alterations ◽  
Mesenchymal Transition

Abstract The survival of children with diffuse intrinsic pontine glioma (DIPG) remains dismal, with new treatments desperately needed. In the era of precision medicine, targeted therapies represent an exciting treatment opportunity, yet resistance can rapidly emerge, playing an important role in treatment failure. In a prospective biopsy-stratified clinical trial, we combined detailed molecular profiling (methylation BeadArray, exome, RNAseq, phospho-proteomics) linked to drug screening in newly-established patient-derived models of DIPG in vitro and in vivo. We identified a high degree of in vitro sensitivity to the MEK inhibitor trametinib (GI50 16-50nM) in samples, which harboured genetic alterations targeting the MAPK pathway, including the non-canonical BRAF_G469V mutation, and those affecting PIK3R1 and NF1. However, treatment of PDX models and of a patient with trametinib at relapse failed to elicit a significant response. We generated trametinib-resistant clones (62-188-fold, GI50 2.4–5.2µM) in the BRAF_G469V model through continuous drug exposure, and identified acquired mutations in MEK1/2 (MEK1_K57N, MEK1_I141S and MEK2_I115N) with sustained pathway up-regulation. These cells showed the hallmarks of mesenchymal transition, and expression signatures overlapping with inherently trametinib-insensitive primary patient-derived cells that predicted an observed sensitivity to dasatinib. Combinations of trametinib with dasatinib and the downstream ERK inhibitor ulixertinib showed highly synergistic effects in vitro. These data highlight the MAPK pathway as a therapeutic target in DIPG, and show the importance of parallel resistance modelling and rational combinatorial treatments likely to be required for meaningful clinical translation.

Emergence of ceftazidime/avibactam resistance in KPC-3-producing Klebsiella pneumoniae in vivo

2019 ◽  
Vol 74 (11) ◽  
pp. 3211-3216 ◽  
Author(s):  
Stephan Göttig ◽  
Denia Frank ◽  
Eleonora Mungo ◽  
Anika Nolte ◽  
Michael Hogardt ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Klebsiella Pneumoniae ◽  
Selection Pressure ◽  
Galleria Mellonella ◽  
Phenotypic Characterization ◽  
Infection Model ◽  
Development Of Resistance ◽  
Time Kill

Abstract Objectives The β-lactam/β-lactamase inhibitor combination ceftazidime/avibactam is active against KPC-producing Enterobacterales. Herein, we present molecular and phenotypic characterization of ceftazidime/avibactam resistance in KPC-3-producing Klebsiella pneumoniae that emerged in vivo and in vitro. Methods Sequence analysis of blaKPC-3 was performed from clinical and in vitro-generated ceftazidime/avibactam-resistant K. pneumoniae isolates. Time–kill kinetics and the Galleria mellonella infection model were applied to evaluate the activity of ceftazidime/avibactam and imipenem alone and in combination. Results The ceftazidime/avibactam-resistant clinical K. pneumoniae isolate revealed the amino acid change D179Y in KPC-3. Sixteen novel mutational changes in KPC-3 among in vitro-selected ceftazidime/avibactam-resistant isolates were described. Time–kill kinetics showed the emergence of a resistant subpopulation under selection pressure with either imipenem or ceftazidime/avibactam. However, combined selection pressure with imipenem plus ceftazidime/avibactam prevented the development of resistance and resulted in bactericidal activity. Concordantly, the G. mellonella infection model revealed that monotherapy with ceftazidime/avibactam is prone to select for resistance in vivo and that combination therapy with imipenem results in significantly better survival. Conclusions Ceftazidime/avibactam is a valuable antibiotic against MDR and carbapenem-resistant Enterobacterales. Based on time–kill kinetics as well as an in vivo infection model we postulate a combination therapy of ceftazidime/avibactam and imipenem as a strategy to prevent the development of ceftazidime/avibactam resistance in KPC-producing Enterobacterales in vivo.

scholarly journals A Preclinical Evaluation of the Antitumor Activities of Edible and Medicinal Mushrooms: A Molecular Insight

2017 ◽  
Vol 17 (2) ◽  
pp. 200-209 ◽  
Author(s):  
Thomson Patrick Joseph ◽  
Warren Chanda ◽  
Arshad Ahmed Padhiar ◽  
Samana Batool ◽  
Shao LiQun ◽  
...  
Keyword(s):  
Side Effects ◽  
Biological Activities ◽  
Genetic Alterations ◽  
In Vivo Models ◽  
Medicinal Mushrooms ◽  
Chemotherapy Drugs ◽  
Development Of Resistance ◽  
Preclinical And Clinical Studies

Cancer is the leading cause of morbidity and mortality around the globe. For certain types of cancer, chemotherapy drugs have been extensively used for treatment. However, severe side effects and the development of resistance are the drawbacks of these agents. Therefore, development of new agents with no or minimal side effects is of utmost importance. In this regard, natural compounds are well recognized as drugs in several human ailments, including cancer. One class of fungi, “mushrooms,” contains numerous compounds that exhibit interesting biological activities, including antitumor activity. Many researchers, including our own group, are focusing on the anticancer potential of different mushrooms and the underlying molecular mechanism behind their action. The aim of this review is to discuss PI3K/AKT, Wnt-CTNNB1, and NF-κB signaling pathways, the occurrence of genetic alterations in them, the association of these aberrations with different human cancers and how different nodes of these pathways are targeted by various substances of mushroom origin. We have given evidence to propose the therapeutic attributes and possible mode of molecular actions of various mushroom-originated compounds. However, anticancer effects were typically demonstrated in in vitro and in vivo models and very limited number of studies have been conducted in the human population. It is our belief that this review will help the research community in designing concrete preclinical and clinical studies to test the anticancer potential of mushroom-originated compounds on different cancers harboring particular genetic alteration(s).

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