Amphiphilic Photoluminescent Porous Silicon Nanoparticles as Effective Agents for Ultrasound-Amplified Cancer Therapy.

This study investigates the use of photoluminescent amphiphilic porous silicon nanoparticles (αϕ-pSiNPs) as effective ultrasound (US) amplifiers for cancer sonodynamic theranostics. αϕ-pSiNPs were synthesized via a novel top-down approach involving porous silicon (pSi) films electrochemical etching, borate oxidation, and hydrophobic coating with octadecylsilane (C18), resulting in milling into nanoparticles with hydrophilic exteriors and hydrophobic interiors. These properties promote gas trapping and cavitation nucleation, significantly lowering the US cavitation threshold and resulting in selective destruction of cancer cells in the presence of nanoparticles.

Ally or traitor: the dual role of p62 in caspase-2 regulation.

Caspase-2 is a unique and conserved cysteine protease that is involved in several cellular processes, including different forms of cell death, maintenance of genomic stability, and the response to reactive oxygen species. Despite advances in caspase-2 research in recent years, the mechanisms underlying its activation remain largely unclear. Although caspase-2 is activated in the PIDDosome complex, its processing could occur even in the absence of PIDD1 and/or RAIDD, suggesting the existence of an alternative platform for caspase-2 activation.

Universal Adapter Protein Bag3 and Small Heat Shock Proteins.

Bag3 (Bcl-2-associated athanogene 3) protein contains a number of functional domains and interacts with a wide range of different partner proteins, including small heat shock proteins (sHsps) and heat shock protein Hsp70. The ternary Bag3-sHsp-and Hsp70 complex binds denatured proteins and transports them to phagosomes, thus playing a key role in the chaperone-assisted selective autophagy (CASA). This complex also participates in the control of formation and disassembly of stress granules (granulostasis) and cytoskeleton regulation.

Noradrenaline and serotonin-dependent sensitization of MSCs to noradrenaline.

Stem and progenitor cells are characterized by peculiar mechanisms of hormonal regulation. Here we describe a protocol of analysis of hormonal cross-talk in adipose tissue derived multipotent mesenchymal stem cells (MSCs). Specifically, cells were treated by a "sensitizing" hormone/neuromediator followed by the measurement of cellular Ca2+ response to the "readout" hormone after various time intervals.

Peripheral 5-HT/HTR6 axis is responsible for obesity-associated hypertension.

Hypertension is one of the major life-threatening complications of obesity. Recently adipose multipotent mesenchymal stromal cells (MSCs) were implicated to the pathogenesis of obesity-associated hypertension. These cells amplify noradrenaline-induced vascular cell contraction via cAMP-mediated signaling pathway.

Complex Analysis of Single-Cell RNA Sequencing Data.

Single-cell RNA sequencing (scRNA-seq) is a revolutionary tool for studying the physiology of normal and pathologically altered tissues. This approach provides information about molecular features (gene expression, mutations, chromatin accessibility, etc.) of cells, opens up the possibility to analyze the trajectories/phylogeny of cell differentiation and cell-cell interactions, and helps in discovery of new cell types and previously unexplored processes.

GPCRs in the regulation of the functional activity of multipotent mesenchymal stromal cells.

Adipose tissue is one of the tissues in the human body that is renewed during the whole life. Dysregulation of this process leads to conditions such as obesity, metabolic syndrome, and type 2 diabetes. The key role in maintaining the healthy state of adipose tissue is played by a specific group of postnatal stem cells called multipotent mesenchymal stromal cells (MSCs).

Mesenchymal stromal cells enhance self-assembly of a HUVEC tubular network through uPA-uPAR/VEGFR2/integrin/NOTCH crosstalk.

Endothelial cells (ECs) degrade the extracellular matrix of vessel walls and contact surrounding cells to facilitate migration during angiogenesis, leading to formation of an EC-tubular network (ETN). Mesenchymal stromal cells (MSC) support ETN formation when co-cultured with ECs, but the mechanism is incompletely understood. We examined the role of the urokinase-type plasminogen activator (uPA) system, i.

Functional Heterogeneity of Protein Kinase A Activation in Multipotent Stromal Cells.

Multipotent stromal cells (MSC) demonstrate remarkable functional heterogeneity; however, its molecular mechanisms remain largely obscure. In this study, we explored MSC response to hormones, which activate Gs-protein / cyclic AMP (cAMP) / protein kinase A (PKA) dependent signaling, at the single cell level using genetically encoded biosensor PKA-Spark. For the first time, we demonstrated that about half of cultured MSCs are not able to activate the cAMP/PKA pathway, possibly due to the limited availability of adenylyl cyclases.

Ultrasensitive Genetically Encoded Indicator for Hydrogen Peroxide Identifies Roles for the Oxidant in Cell Migration and Mitochondrial Function.

Hydrogen peroxide (HO) is a key redox intermediate generated within cells. Existing probes for HO have not solved the problem of detection of the ultra-low concentrations of the oxidant: these reporters are not sensitive enough, or pH-dependent, or insufficiently bright, or not functional in mammalian cells, or have poor dynamic range. Here we present HyPer7, the first bright, pH-stable, ultrafast, and ultrasensitive ratiometric HO probe.

Angiotensin receptor subtypes regulate adipose tissue renewal and remodelling.

Obesity is often associated with high systemic and local renin-angiotensin system (RAS) activity in adipose tissue. Adipose-derived mesenchymal stem/stromal cells (ADSCs), responsible for adipose tissue growth upon high-fat diet, express multiple angiotensin II receptor isoforms, including angiotensin II type 1 receptor (AT R), angiotensin II type 2 receptor (AT R), Mas and Mas-related G protein-coupled receptor D. Although AT R is expressed on most ADSCs, other angiotensin receptors are co-expressed on a small subpopulation of the cells, a phenomenon that results in a complex response pattern.

Analysis of novel hyperosmotic shock response suggests 'beads in liquid' cytosol structure.

Proteins can aggregate in response to stresses, including hyperosmotic shock. Formation and disassembly of aggregates is a relatively slow process. We describe a novel instant response of the cell to hyperosmosis, during which chaperones and other proteins form numerous foci with properties uncharacteristic of classical aggregates.

Optimization of CRISPR/Cas9 Technology to Knock Out Genes of Interest in Aneuploid Cell Lines.

Cell lines represent convenient models to elucidate specific causes of multigenetic and pluricausal diseases, to test breakthrough regenerative technologies. Most commonly used cell lines surpass diploid cells in their accessibility for delivery of large DNA molecules and genome editing, but the main obstacles for obtaining cell models with knockout-targeted protein from aneuploid cells are multiple allele copies and karyotype/phenotype heterogeneity. In the study, we report an original approach to CRISPR-/Cas9-mediated genome modification of aneuploid cell cultures to create functional cell models, achieving highly efficient targeted protein knockout and avoiding "clonal effect" (for the first time to our knowledge).

Noradrenaline Sensitivity Is Severely Impaired in Immortalized Adipose-Derived Mesenchymal Stem Cell Line.

Primary adipose tissue-derived multipotent stem/stromal cells (adMSCs) demonstrate unusual signaling regulatory mechanisms, i.e., increased of sensitivity to catecholamines in response to noradrenaline.

2-Deoxy-D-glucose has distinct and cell line-specific effects on the survival of different cancer cells upon antitumor drug treatment.

The dependence of tumors on glycolysis for ATP generation offers a rationale for therapeutic strategies aimed at selective inhibition of the glycolytic pathway. Analysis of tumor cell responses to anticancer drugs revealed that inhibition of glycolysis by 2-deoxy-D-glucose (2-DG) generally augmented the apoptotic response; however, in HCT116 human colon carcinoma cells, apoptosis was suppressed. A comparison of neuroblastoma SK-N-BE(2) and HCT116 cells revealed, that in contrast to HCT116, in SK-N-BE(2) cells 2-DG alone was able to induce cell death.

Flow cytometry analysis of adrenoceptors expression in human adipose-derived mesenchymal stem/stromal cells.

Mesenchymal stem/stromal cells (MSCs) were identified in most tissues of an adult organism. MSCs mediate physiological renewal, as well as regulation of tissue homeostasis, reparation and regeneration. Functions of MSCs are regulated by endocrine and neuronal signals, and noradrenaline is one of the most important MSC regulators.

CRISPR/Cas9-mediated modification of the extreme C-terminus impairs PDGF-stimulated activity of Duox2.

Duox2 belongs to the large family of NADPH-oxidase enzymes that are implicated in immune response, vasoregulation, hormone synthesis, cell growth and differentiation via the regulated synthesis of H2O2 and reactive oxygen species. We and others have shown that Duox2 and H2O2 are involved in platelet-derived growth factor (PDGF) induced migration of fibroblasts. Now, using the CRISPR/Cas9-mediated genome editing we demonstrate that the extreme C-terminal region of Duox2 is required for PDGF-stimulated activity of Duox2 and H2O2 production.

Data supporting that adipose-derived mesenchymal stem/stromal cells express angiotensin II receptors in situ and in vitro.

This article contains results of analyses of angiotensin II receptors expression in human adipose tissue and stem/stromal cells isolated from adipose tissue. We also provide here data regarding the effect of angiotensin II on intracellular calcium mobilization in adipose tissue derived stem/stromal cells (ADSCs). Discussion of the data can be found in (Sysoeva et al.

Local angiotensin II promotes adipogenic differentiation of human adipose tissue mesenchymal stem cells through type 2 angiotensin receptor.

Obesity is often associated with high systemic and local activity of renin-angiotensin system (RAS). Mesenchymal stem cells of adipose tissue are the main source of adipocytes. The aim of this study was to clarify how local RAS could control adipose differentiation of human adipose tissue derived mesenchymal stem cells (ADSCs).

Involvement of autophagy in the outcome of mitotic catastrophe.

Evading cell death is a major driving force for tumor progression that is one of the main problems in current cancer research. Mitotic catastrophe (MC) represents attractive platform compromising tumor resistance to current therapeutic modalities. MC appeared as onco-suppressive mechanism and is defined as a stage driving the cell to an irreversible destiny, i.

Activation of β-adrenergic receptors is required for elevated α1A-adrenoreceptors expression and signaling in mesenchymal stromal cells.

Sympathetic neurons are important components of mesenchymal stem cells (MSCs) niche and noradrenaline regulates biological activities of these cells. Here we examined the mechanisms of regulation of MSCs responsiveness to noradrenaline. Using flow cytometry, we demonstrated that α1A adrenergic receptors isoform was the most abundant in adipose tissue-derived MSCs.

Nox4 and Duox1/2 Mediate Redox Activation of Mesenchymal Cell Migration by PDGF.

Platelet derived growth factor (PDGF) orchestrates wound healing and tissue regeneration by regulating recruitment of the precursor mesenchymal stromal cells (MSC) and fibroblasts. PDGF stimulates generation of hydrogen peroxide that is required for cell migration, but the sources and intracellular targets of H2O2 remain obscure. Here we demonstrate sustained live responses of H2O2 to PDGF and identify PKB/Akt, but not Erk1/2, as the target for redox regulation in cultured 3T3 fibroblasts and MSC.

Chemotactic signaling in mesenchymal cells compared to amoeboid cells.

Cell chemotaxis plays a pivotal role in normal development, inflammatory response, injury repair and tissue regeneration in all organisms. It is also a critical contributor to cancer metastasis, altered angiogenesis and neurite growth in disease. The molecular mechanisms regulating chemotaxis are currently being identified and key components may be pertinent therapeutic targets.

Functional expression of adrenoreceptors in mesenchymal stromal cells derived from the human adipose tissue.

Cultured mesenchymal stromal cells (MSCs) from different sources represent a heterogeneous population of proliferating non-differentiated cells that contains multipotent stem cells capable of originating a variety of mesenchymal cell lineages. Despite tremendous progress in MSC biology spurred by their therapeutic potential, current knowledge on receptor and signaling systems of MSCs is mediocre. Here we isolated MSCs from the human adipose tissue and assayed their responsivity to GPCR agonists with Ca(2+) imaging.