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BMC Neuroscience Jan 2021Status epilepticus (SE) is a life-threatening neurological disorder. The hippocampus, as an important area of the brain that regulates cognitive function, is usually...
BACKGROUND
Status epilepticus (SE) is a life-threatening neurological disorder. The hippocampus, as an important area of the brain that regulates cognitive function, is usually damaged after SE, and cognitive deficits often result from hippocampal neurons lost after SE. Fyn, a non-receptor Src family of tyrosine kinases, is potentially associated with the onset of seizure. Saracatinib, a Fyn inhibitor, suppresses epileptogenesis and reduces epileptiform spikes. However, whether saracatinib inhibits cognitive deficits after SE is still unknown.
METHODS
In the present study, a pilocarpine-induced SE mouse model was used to answer this question by using the Morris water maze and normal object recognition behavioral tests.
RESULTS
We found that saracatinib inhibited the loss in cognitive function following SE. Furthermore, we found that the number of hippocampal neurons in the saracatinib treatment group was increased, when compared to the SE group.
CONCLUSIONS
These results showed that saracatinib can improve cognitive functions by reducing the loss of hippocampal neurons after SE, suggesting that Fyn dysfunction is involved in cognitive deficits after SE, and that the inhibition of Fyn is a possible treatment to improve cognitive function in SE patients.
Topics: Animals; Benzodioxoles; Cognition; Cognitive Dysfunction; Enzyme Inhibitors; Hippocampus; Male; Mice; Mice, Inbred C57BL; Neurons; Proto-Oncogene Proteins c-fyn; Quinazolines; Status Epilepticus
PubMed: 33451301
DOI: 10.1186/s12868-020-00606-z -
Stem Cell Reviews and Reports Jun 2021Balanced signal transduction is crucial in tissue patterning, particularly in the vasculature. Heterotopic ossification (HO) is tightly linked to vascularization with...
Balanced signal transduction is crucial in tissue patterning, particularly in the vasculature. Heterotopic ossification (HO) is tightly linked to vascularization with increased vessel number in hereditary forms of HO, such as Fibrodysplasia ossificans progressiva (FOP). FOP is caused by mutations in the BMP type I receptor ACVR1 leading to aberrant SMAD1/5 signaling in response to ActivinA. Whether observed vascular phenotype in human FOP lesions is connected to aberrant ActivinA signaling is unknown. Blocking of ActivinA prevents HO in FOP mice indicating a central role of the ligand in FOP. Here, we established a new FOP endothelial cell model generated from induced pluripotent stem cells (iECs) to study ActivinA signaling. FOP iECs recapitulate pathogenic ActivinA/SMAD1/5 signaling. Whole transcriptome analysis identified ActivinA mediated activation of the BMP/NOTCH pathway exclusively in FOP iECs, which was rescued to WT transcriptional levels by the drug candidate Saracatinib. We propose that ActivinA causes transcriptional pre-patterning of the FOP endothelium, which might contribute to differential vascularity in FOP lesions compared to non-hereditary HO.
Topics: Animals; Benzodioxoles; Induced Pluripotent Stem Cells; Mice; Myositis Ossificans; Quinazolines; Signal Transduction; Smad1 Protein; Smad5 Protein
PubMed: 33410098
DOI: 10.1007/s12015-020-10103-9 -
Clinical Cancer Research : An Official... Mar 2021Alterations in DNA damage repair (DDR) pathway genes occur in 20%-25% of men with metastatic castration-resistant prostate cancer (mCRPC). Although PARP inhibitors...
PURPOSE
Alterations in DNA damage repair (DDR) pathway genes occur in 20%-25% of men with metastatic castration-resistant prostate cancer (mCRPC). Although PARP inhibitors (PARPis) have been shown to benefit men with mCRPC harboring DDR defects due to mutations in and ATM, additional treatments are necessary because the effects are not durable.
EXPERIMENTAL DESIGN
We performed transcriptomic analysis of publicly available mCRPC cases, comparing null with wild-type. We generated -null prostate cancer cells using CRISPR/Cas9 and treated these cells with PARPis and SRC inhibitors. We also assessed the antiproliferative effects of combination treatment in 3D prostate cancer organoids.
RESULTS
We observed significant enrichment of the SRC signaling pathway in -altered mCRPC. -null prostate cancer cell lines had increased SRC phosphorylation and higher sensitivity to SRC inhibitors (e.g., dasatinib, bosutinib, and saracatinib) relative to wild-type cells. Combination treatment with PARPis and SRC inhibitors was antiproliferative and had a synergistic effect in -null prostate cancer cells, mCRPC organoids, and Trp53/Rb1-null prostate cancer cells. Inhibition of SRC signaling by dasatinib augmented DNA damage in -null prostate cancer cells. Moreover, knockdown increased PARPi sensitivity in -null prostate cancer cells.
CONCLUSIONS
This work suggests that SRC activation may be a potential mechanism of PARPi resistance and that treatment with SRC inhibitors may overcome this resistance. Our preclinical study demonstrates that combining PARPis and SRC inhibitors may be a promising therapeutic strategy for patients with -null mCRPC.
Topics: Animals; Antineoplastic Agents; Apoptosis; BRCA2 Protein; Cell Proliferation; Drug Synergism; Drug Therapy, Combination; Gene Expression Regulation, Neoplastic; Humans; Male; Mice; Mice, Nude; Poly(ADP-ribose) Polymerase Inhibitors; Prognosis; Prostatic Neoplasms, Castration-Resistant; Survival Rate; Synthetic Lethal Mutations; Tumor Cells, Cultured; Xenograft Model Antitumor Assays; src-Family Kinases
PubMed: 33334906
DOI: 10.1158/1078-0432.CCR-20-2483 -
Biotechnology Progress Mar 2021The recent outbreak of coronavirus disease (COVID-19) in China caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to worldwide human...
The recent outbreak of coronavirus disease (COVID-19) in China caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to worldwide human infections and deaths. The nucleocapsid (N) protein of coronaviruses (CoVs) is a multifunctional RNA binding protein necessary for viral RNA replication and transcription. Therefore, it is a potential antiviral drug target, serving multiple critical functions during the viral life cycle. This study addresses the potential to repurpose antiviral compounds approved or in development for treating human CoV induced infections against SARS-CoV-2 N. For this purpose, we used the docking methodology to better understand the inhibitory mechanism of this protein with the existing 34 antiviral compounds. The results of this analysis indicate that rapamycin, saracatinib, camostat, trametinib, and nafamostat were the top hit compounds with binding energy (-11.87, -10.40, -9.85, -9.45, -9.35 kcal/mol, respectively). This analysis also showed that the most common residues that interact with the compounds are Phe66, Arg68, Gly69, Tyr123, Ile131, Trp132, Val133, and Ala134. Subsequently, protein-ligand complex stability was examined with molecular dynamics simulations for these five compounds, which showed the best binding affinity. According to the results of this study, the interaction between these compounds and crucial residues of the target protein were maintained. These results suggest that these residues are potential drug targeting sites for the SARS-CoV-2 N protein. This study information will contribute to the development of novel compounds for further in vitro and in vivo studies of SARS-CoV-2, as well as possible new drug repurposing strategies to treat COVID-19 disease.
Topics: Amino Acid Sequence; Antiviral Agents; Binding Sites; Coronavirus Nucleocapsid Proteins; Drug Design; Drug Repositioning; Molecular Docking Simulation; Molecular Dynamics Simulation; Phosphoproteins; Protein Domains; SARS-CoV-2
PubMed: 33314794
DOI: 10.1002/btpr.3110 -
International Journal of Molecular... Dec 2020Dasatinib is a multi-target kinase inhibitor, whose targets include BCR-ABL, SRC family kinases, and various cancer kinases. The elevated SRC activity in gastric cancer...
Dasatinib is a multi-target kinase inhibitor, whose targets include BCR-ABL, SRC family kinases, and various cancer kinases. The elevated SRC activity in gastric cancer (GC) has prompted the need for the therapeutic application of dasatinib in GC. We observed that the efficacy of dasatinib varied with the GC cell lines. The differential effect of dasatinib was not correlated with the basal SRC activity of each cell line. Moreover, the GC cell lines showing the strong antitumor effects of dasatinib were refractory to other SRC inhibitors, i.e., bosutinib and saracatinib, suggesting that unexpected dasatinib's targets could exist. To profile the targets of dasatinib in GC, we performed activity-based protein profiling (ABPP) via mass spectrometry using a desthiobiotin-ATP probe. We identified 29 and 18 kinases as potential targets in dasatinib-sensitive (SNU-216, MKN-1) and -resistant (SNU-484, SNU-601) cell lines, respectively. The protein-protein interaction mapping of the differential drug targets in dasatinib-sensitive and -resistant GC using the STRING database suggested that dasatinib could target cellular energy homeostasis in the drug-sensitive GC. RNAi screening for identified targets indicated p90RSK could be a novel dasatinib target, which is important for maintaining the viability and motility of GC cells. Further functional validation of dasatinib off-target actions will provide more effective therapeutic options for GC.
Topics: Apoptosis; Biomarkers, Tumor; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Chromatography, Liquid; Dasatinib; Humans; Molecular Targeted Therapy; Phenotype; Protein Kinase Inhibitors; Proteome; Proteomics; Stomach Neoplasms; Tandem Mass Spectrometry
PubMed: 33291786
DOI: 10.3390/ijms21239276 -
European Journal of Medicinal Chemistry Jan 2021Alzheimer's disease (AD) is the most common form of dementia characterized by presence of extracellular amyloid plaques and intracellular neurofibrillary tangles... (Review)
Review
Alzheimer's disease (AD) is the most common form of dementia characterized by presence of extracellular amyloid plaques and intracellular neurofibrillary tangles composed of tau protein. Currently there are close to 50 million people living with dementia and this figure is expected to increase to 75 million by 2030 putting a huge burden on the economy due to the health care cost. Considering the effects on quality of life of patients and the increasing burden on the economy, there is an enormous need of new disease modifying therapies to tackle this disease. The current therapies are dominated by only symptomatic treatments including cholinesterase inhibitors and N-methyl-D-aspartate receptor blockers but no disease modifying treatments exist so far. After several failed attempts to develop drugs against amyloidopathy, tau targeting approaches have been in the main focus of drug development against AD. After an overview of the tauopathy in AD, this review summarizes recent findings on the development of small molecules as therapeutics targeting tau modification, aggregation, and degradation, and tau-oriented multi-target directed ligands. Overall, this work aims to provide a comprehensive and critical overview of small molecules which are being explored as a lead candidate for discovering drugs against tauopathy in AD.
Topics: Alzheimer Disease; Animals; Benzodioxoles; Cholinesterase Inhibitors; Cholinesterases; Curcumin; Humans; Molecular Targeted Therapy; Neurofibrillary Tangles; Neuroprotective Agents; Phosphorylation; Plaque, Amyloid; Protein Aggregation, Pathological; Protein Processing, Post-Translational; Quinazolines; Receptors, N-Methyl-D-Aspartate; Thiadiazoles; tau Proteins
PubMed: 33139110
DOI: 10.1016/j.ejmech.2020.112915 -
Biomedicines Sep 2020Fibrodysplasia ossificans progressiva (FOP) is an extremely rare heritable disorder of connective tissues characterized by progressive heterotopic ossification in... (Review)
Review
Fibrodysplasia ossificans progressiva (FOP) is an extremely rare heritable disorder of connective tissues characterized by progressive heterotopic ossification in various skeletal sites. It is caused by gain-of-function mutations in the gene encoding activin A receptor type I ()/activin-like kinase 2 (), a bone morphogenetic protein (BMP) type I receptor. Heterotopic ossification is usually progressive leading to severe deformities in the trunk and extremities. Early clinical diagnosis is important to prevent unnecessary iatrogenic harm or trauma. Clinicians should become aware of early detectable skeletal malformations, including great toe deformities, shortened thumb, neck stiffness associated with hypertrophy of the posterior elements of the cervical spine, multiple ossification centers in the calcaneus, and osteochondroma-like lesions of the long bones. Although there is presently no definitive medical treatment to prevent, stop or reverse heterotopic ossification in FOP, exciting advances of novel pharmacological drugs focusing on target inhibition of the activated receptor, including palovarotene, REGN 2477, rapamycin, and saracatinib, have developed and are currently in clinical trials.
PubMed: 32887348
DOI: 10.3390/biomedicines8090325 -
RNA Biology Mar 2021Epithelial-to-mesenchymal transition (EMT) is a hallmark of aggressive, mesenchymal-like high-grade serous ovarian carcinoma (HGSOC). The SRC kinase is a key driver of...
Epithelial-to-mesenchymal transition (EMT) is a hallmark of aggressive, mesenchymal-like high-grade serous ovarian carcinoma (HGSOC). The SRC kinase is a key driver of cancer-associated EMT promoting adherens junction (AJ) disassembly by phosphorylation-driven internalization and degradation of AJ proteins. Here, we show that the IGF2 mRNA-binding protein 1 (IGF2BP1) is up-regulated in mesenchymal-like HGSOC and promotes SRC activation by a previously unknown protein-ligand-induced, but RNA-independent mechanism. IGF2BP1-driven invasive growth of ovarian cancer cells essentially relies on the SRC-dependent disassembly of AJs. Concomitantly, IGF2BP1 enhances ERK2 expression in an RNA-binding dependent manner. Together this reveals a post-transcriptional mechanism of interconnected stimulation of SRC/ERK signalling in ovarian cancer cells. The IGF2BP1-SRC/ERK2 axis is targetable by the SRC-inhibitor saracatinib and MEK-inhibitor selumetinib. However, due to IGF2BP1-directed stimulation, only combinatorial treatment effectively overcomes the IGF2BP1-promoted invasive growth in 3D culture conditions as well as intraperitoneal mouse models. In conclusion, we reveal an unexpected role of IGF2BP1 in enhancing SRC/MAPK-driven invasive growth of ovarian cancer cells. This provides a rationale for the therapeutic benefit of combinatorial SRC/MEK inhibition in mesenchymal-like HGSOC.
Topics: Adherens Junctions; Animals; Biomarkers, Tumor; Cell Line, Tumor; Disease Models, Animal; Epithelial-Mesenchymal Transition; Female; Gene Expression Regulation, Neoplastic; Humans; Mice; Mitogen-Activated Protein Kinases; Ovarian Neoplasms; Protein Binding; Protein Interaction Domains and Motifs; Protein Kinase Inhibitors; RNA-Binding Proteins; Signal Transduction; Xenograft Model Antitumor Assays; src Homology Domains; src-Family Kinases
PubMed: 32876513
DOI: 10.1080/15476286.2020.1812894 -
PloS One 2020Tauopathies are a class of neurodegenerative disorders characterized by abnormal deposition of post-translationally modified tau protein in the human brain. Tauopathies...
Tauopathies are a class of neurodegenerative disorders characterized by abnormal deposition of post-translationally modified tau protein in the human brain. Tauopathies are associated with Alzheimer's disease (AD), chronic traumatic encephalopathy (CTE), and other diseases. Hyperphosphorylation increases tau tendency to aggregate and form neurofibrillary tangles (NFT), a pathological hallmark of AD. In this study, okadaic acid (OA, 100 nM), a protein phosphatase 1/2A inhibitor, was treated for 24h in mouse neuroblastoma (N2a) and differentiated rat primary neuronal cortical cell cultures (CTX) to induce tau-hyperphosphorylation and oligomerization as a cell-based tauopathy model. Following the treatments, the effectiveness of different kinase inhibitors was assessed using the tauopathy-relevant tau antibodies through tau-immunoblotting, including the sites: pSer202/pThr205 (AT8), pThr181 (AT270), pSer202 (CP13), pSer396/pSer404 (PHF-1), and pThr231 (RZ3). OA-treated samples induced tau phosphorylation and oligomerization at all tested epitopes, forming a monomeric band (46-67 kDa) and oligomeric bands (170 kDa and 240 kDa). We found that TBB (a casein kinase II inhibitor), AR and LiCl (GSK-3 inhibitors), cyclosporin A (calcineurin inhibitor), and Saracatinib (Fyn kinase inhibitor) caused robust inhibition of OA-induced monomeric and oligomeric p-tau in both N2a and CTX culture. Additionally, a cyclin-dependent kinase 5 inhibitor (Roscovitine) and a calcium chelator (EGTA) showed contrasting results between the two neuronal cultures. This study provides a comprehensive view of potential drug candidates (TBB, CsA, AR, and Saracatinib), and their efficacy against tau hyperphosphorylation and oligomerization processes. These findings warrant further experimentation, possibly including animal models of tauopathies, which may provide a putative Neurotherapy for AD, CTE, and other forms of tauopathy-induced neurodegenerative diseases.
Topics: Animals; Cell Line; Cyclosporine; Glycogen Synthase Kinase 3; Lithium Chloride; Mice; Models, Biological; Okadaic Acid; Phosphorylation; Protein Kinase Inhibitors; Protein Multimerization; Rats; Tauopathies; Triazoles
PubMed: 32692785
DOI: 10.1371/journal.pone.0224952 -
Acta Neuropathologica Communications Jul 2020Accumulation of misfolded phosphorylated Tau (Tauopathy) can be triggered by mutations or by trauma, and is associated with synapse loss, gliosis, neurodegeneration and...
Accumulation of misfolded phosphorylated Tau (Tauopathy) can be triggered by mutations or by trauma, and is associated with synapse loss, gliosis, neurodegeneration and memory deficits. Fyn kinase physically associates with Tau and regulates subcellular distribution. Here, we assessed whether pharmacological Fyn inhibition alters Tauopathy. In P301S transgenic mice, chronic Fyn inhibition prevented deficits in spatial memory and passive avoidance learning. The behavioral improvement was coupled with reduced accumulation of phospho-Tau in the hippocampus, with reductions in glial activation and with recovery of presynaptic markers. We extended this analysis to a trauma model in which very mild repetitive closed head injury was paired with chronic variable stress over 2 weeks to produce persistent memory deficits and Tau accumulation. In this model, Fyn inhibition beginning 24 h after the trauma ended rescued memory performance and reduced phospho-Tau accumulation. Thus, inhibition of Fyn kinase may have therapeutic benefit in clinical Tauopathies.
Topics: Aged, 80 and over; Animals; Benzodioxoles; Brain Concussion; Enzyme Inhibitors; Humans; Male; Memory Disorders; Mice; Mice, Transgenic; Protein Aggregates; Protein Aggregation, Pathological; Proto-Oncogene Proteins c-fyn; Quinazolines; Synapses; Tauopathies; tau Proteins
PubMed: 32611392
DOI: 10.1186/s40478-020-00976-9