Mutational scanning pinpoints distinct binding sites of key ATGL regulators in lipolysis.

ATGL is a key enzyme in intracellular lipolysis and plays an important role in metabolic and cardiovascular diseases. ATGL is tightly regulated by a known set of protein-protein interaction partners with activating or inhibiting functions in the control of lipolysis. Here, we use deep mutational protein interaction perturbation scanning and generate comprehensive profiles of single amino acid variants that affect the interactions of ATGL with its regulatory partners: CGI-58, G0S2, PLIN1, PLIN5 and CIDEC.

Biomimetic Mineralization of Iron-Fumarate Nanoparticles for Protective Encapsulation and Intracellular Delivery of Proteins.

Biomimetic mineralization of proteins and nucleic acids into hybrid metal-organic nanoparticles allows for protection and cellular delivery of these sensitive and generally membrane-impermeable biomolecules. Although the concept is not necessarily restricted to zeolitic imidazolate frameworks (ZIFs), so far reports about intracellular delivery of functional proteins have focused on ZIF structures. Here, we present a green room-temperature synthesis of amorphous iron-fumarate nanoparticles under mildly acidic conditions in water to encapsulate bovine serum albumin (BSA), horseradish peroxidase (HRP), green fluorescent protein (GFP), and Cas9/sgRNA ribonucleoproteins (RNPs).

Mesoporous Biodegradable Magnesium Phosphate-Citrate Nanocarriers Amplify Methotrexate Anticancer Activity in HeLa Cells.

We present the synthesis of amorphous, mesoporous, colloidal magnesium phosphate-citrate nanoparticles (MPCs) from biogenic precursors, resulting in a biocompatible and biodegradable nanocarrier that amplifies the action of the anticancer drug methotrexate (MTX). Synthesis conditions were gradually tuned to investigate the influence of the chelating agent citric acid on the colloidal stability and the mesoporosity of the obtained nanoparticles. With optimized synthesis conditions, a large BET surface area of 560 m/g was achieved.

Directed invasion of cancer cell spheroids inside 3D collagen matrices oriented by microfluidic flow in experiment and simulation.

Invasion is strongly influenced by the mechanical properties of the extracellular matrix. Here, we use microfluidics to align fibers of a collagen matrix and study the influence of fiber orientation on invasion from a cancer cell spheroid. The microfluidic setup allows for highly oriented collagen fibers of tangential and radial orientation with respect to the spheroid, which can be described by finite element simulations.

Volumetric measurements of target lesions: does it improve inter-reader variability for oncological response assessment according to RECIST 1.1 guidelines compared to standard unidimensional measurements?

Purpose: Target lesion selection is known to be a major factor for inter-reader discordance in RECIST 1.1. The purpose of this study was to assess whether volumetric measurements of target lesions result in different response categorization, as opposed to standard unidimensional measurements, and to evaluate the impact on inter-reader agreement for response categorization when different readers select different sets of target lesions.

Liquid-liquid phase separation underpins the formation of replication factories in rotaviruses.

RNA viruses induce the formation of subcellular organelles that provide microenvironments conducive to their replication. Here we show that replication factories of rotaviruses represent protein-RNA condensates that are formed via liquid-liquid phase separation of the viroplasm-forming proteins NSP5 and rotavirus RNA chaperone NSP2. Upon mixing, these proteins readily form condensates at physiologically relevant low micromolar concentrations achieved in the cytoplasm of virus-infected cells.

Protocol for photoactivation of YAP in cancer cell spheroids embedded in collagen gels.

This protocol describes the necessary preparations and procedures to photo-activate Yes-associated protein (YAP) with optoYAP in cancer cell spheroids in 3D collagen matrices. We detail steps for immunofluorescent staining of the resulting YAP-activated HeLa spheroids. In addition, we describe handling of optoYAP on 2D substrates.

Spatio-selective activation of nuclear translocation of YAP with light directs invasion of cancer cell spheroids.

The mechanical properties of the extracellular matrix strongly influence tumor progression and invasion. Yes-associated protein (YAP) has been shown to be a key regulator of this process translating mechanical cues from the extracellular matrix into intracellular signals. Despite its apparent role in tumor progression and metastasis, it is not clear yet, whether YAP activation can actively trigger the onset of invasion.

Mesoporous Silica Nanoparticles as pH-Responsive Carrier for the Immune-Activating Drug Resiquimod Enhance the Local Immune Response in Mice.

Nanoparticle-based delivery systems for cancer immunotherapies aim to improve the safety and efficacy of these treatments through local delivery to specialized antigen-presenting cells (APCs). Multifunctional mesoporous silica nanoparticles (MSNs), with their large surface areas, their tunable particle and pore sizes, and their spatially controlled functionalization, represent a safe and versatile carrier system. In this study, we demonstrate the potential of MSNs as a pH-responsive drug carrier system for the anticancer immune-stimulant R848 (resiquimod), a synthetic Toll-like receptor 7 and 8 agonist.

CT-based whole-body tumor volumetry versus RECIST 1.1: Feasibility and implications for inter-reader variability.

Purpose: To investigate whether volumetric measurements of the whole-body tumor volume (WBTV) are feasible and whether they improve inter-reader variability in patients in whom conventional RECIST 1.1 assessment yielded discordant results.

Methods: 50 patients (29 male, 21 female, mean age 60.

Factors That Drive Heterogeneity of Response-to-Treatment of Different Metastatic Deposits Within the Same Patients as Measured by RECIST 1.1 Analyses.

Rationale And Objective: This study uses the rate of between-reader variability under Response Evaluation Criteria for Solid Tumors (RECIST) 1.1 as a metric to estimate the prevalence of biologic heterogeneity of individual metastases, and to determine whether this prevalence is modulated by the type of primary tumor, or type of treatment administered.

Materials And Methods: Three radiologists independently used dedicated oncologic response-assessment software (MintLesion) to prospectively determine RECIST1.

Particle-Size-Dependent Delivery of Antitumoral miRNA Using Targeted Mesoporous Silica Nanoparticles.

Multifunctional core-shell mesoporous silica nanoparticles (MSN) were tailored in size ranging from 60 to 160 nm as delivery agents for antitumoral microRNA (miRNA). The positively charged particle core with a pore diameter of about 5 nm and a stellate pore morphology allowed for an internal, protective adsorption of the fragile miRNA cargo. A negatively charged particle surface enabled the association of a deliberately designed block copolymer with the MSN shell by charge-matching, simultaneously acting as a capping as well as endosomal release agent.

Supersensitive Multifluorophore RNA-FISH for Early Virus Detection and Flow-FISH by Using Click Chemistry.

The reliable detection of transcription events through the quantification of the corresponding mRNA is of paramount importance for the diagnostics of infections and diseases. The quantification and localization analysis of the transcripts of a particular gene allows disease states to be characterized more directly compared to an analysis on the transcriptome wide level. This is particularly needed for the early detection of virus infections as now required for emergent viral diseases, e.

Metal-Organic Framework Nanoparticles Induce Pyroptosis in Cells Controlled by the Extracellular pH.

Ion homeostasis is essential for cellular survival, and elevated concentrations of specific ions are used to start distinct forms of programmed cell death. However, investigating the influence of certain ions on cells in a controlled way has been hampered due to the tight regulation of ion import by cells. Here, it is shown that lipid-coated iron-based metal-organic framework nanoparticles are able to deliver and release high amounts of iron ions into cells.

Fiber stiffness, pore size and adhesion control migratory phenotype of MDA-MB-231 cells in collagen gels.

Cancer cell migration is influenced by cellular phenotype and behavior as well as by the mechanical and chemical properties of the environment. Furthermore, many cancer cells show plasticity of their phenotype and adapt it to the properties of the environment. Here, we study the influence of fiber stiffness, confinement, and adhesion properties on cancer cell migration in porous collagen gels.

Coordinative Binding of Polymers to Metal-Organic Framework Nanoparticles for Control of Interactions at the Biointerface.

Metal-organic framework nanoparticles (MOF NPs) are of growing interest in diagnostic and therapeutic applications, and due to their hybrid nature, they display enhanced properties compared to more established nanomaterials. The effective application of MOF NPs, however, is often hampered by limited control of their surface chemistry and understanding of their interactions at the biointerface. Using a surface coating approach, we found that coordinative polymer binding to Zr- fum NPs is a convenient way for peripheral surface functionalization.

A Chemiluminescent Metal-Organic Framework.

The synthesis and characterization of a chemiluminescent metal-organic framework with high porosity is reported. It consists of Zr O (OH) nodes connected by 4,4'-(anthracene-9,10-diyl)dibenzoate as the linker and luminophore. It shows the topology known for UiO-66 and is therefore denoted PAP-UiO.

Nanoparticle mediated delivery and small molecule triggered activation of proteins in the nucleus.

Protein transfection is a versatile tool to study or manipulate cellular processes and also shows great therapeutic potential. However, the repertoire of cost effective techniques for efficient and minimally cytotoxic delivery remains limited. Mesoporous silica nanoparticles (MSNs) are multifunctional nanocarriers for cellular delivery of a wide range of molecules, they are simple and economical to synthesize and have shown great promise for protein delivery.

Biocompatible crosslinked β-cyclodextrin nanoparticles as multifunctional carriers for cellular delivery.

Nanoparticle-based biomedicine has received enormous attention for theranostic applications, as these systems are expected to overcome several drawbacks of conventional therapy. Herein, effective and controlled drug delivery systems with on-demand release abilities and biocompatible properties are used as a versatile and powerful class of nanocarriers. We report the synthesis of a novel biocompatible and multifunctional material, entirely consisting of covalently crosslinked organic molecules.

Guiding 3D cell migration in deformed synthetic hydrogel microstructures.

The ability of cells to navigate through the extracellular matrix, a network of biopolymers, is controlled by an interplay of cellular activity and mechanical network properties. Synthetic hydrogels with highly tuneable compositions and elastic properties are convenient model systems for the investigation of cell migration in 3D polymer networks. To study the impact of macroscopic deformations on single cell migration, we present a novel method to introduce uniaxial strain in matrices by microstructuring photo-polymerizable hydrogel strips with embedded cells in a channel slide.

Lipid-Coated Zinc Oxide Nanoparticles as Innovative ROS-Generators for Photodynamic Therapy in Cancer Cells.

In the present paper, we use zinc oxide nanoparticles under the excitation of ultraviolet (UV) light for the generation of Reactive Oxygen Species (ROS), with the aim of further using these species for fighting cancer cells in vitro. Owing to the difficulties in obtaining highly dispersed nanoparticles (NPs) in biological media, we propose their coating with a double-lipidic layer and we evaluate their colloidal stability in comparison to the pristine zinc oxide NPs. Then, using Electron Paramagnetic Resonance (EPR) coupled with the spin-trapping technique, we demonstrate and characterize the ability of bare and lipid-coated ZnO NPs to generate ROS in water only when remotely actuated via UV light irradiation.

Liposome-Coated Iron Fumarate Metal-Organic Framework Nanoparticles for Combination Therapy.

One of the main problems for effective treatment of cancer is resistances, which often require combination therapy-for effective treatment. While there are already some potential drug carriers-e.g.

Impact of plasma protein binding on cargo release by thermosensitive liposomes probed by fluorescence correlation spectroscopy.

Thermosensitive liposomes (TSLs) whose phase-transition temperature (T) lies slightly above body temperature are ideal candidates for controlled drug release via local hyperthermia. Recent studies, however, have revealed disruptive shifts in the release temperature T in mouse plasma, which are attributed to undefined interactions with blood proteins. Here, we study the effects of four major plasma proteins - serum albumin (SA), transferrin (Tf), apolipoprotein A1 (ApoA1) and fibrinogen (Fib) - on the temperature-dependent release of fluorescein di-β-D-galactopyranoside (FDG) from TSLs.

Dendrimer-Based Signal Amplification of Click-Labelled DNA in Situ.

The in vivo incorporation of alkyne-modified bases into the genome of cells is today the basis for the efficient detection of cell proliferation. Cells are grown in the presence of ethinyl-dU (EdU), fixed and permeabilised. The incorporated alkynes are then efficiently detected by using azide-containing fluorophores and the Cu -catalysed alkyne-azide click reaction.

Cell membrane penetration and mitochondrial targeting by platinum-decorated ceria nanoparticles.

In this work we investigate the interaction between endothelial cells and nanoparticles emitted by catalytic converters. Although catalyst-derived particles are recognized as growing burden added to environmental pollution, very little is known about their health impact. We use platinum-decorated ceria nanoparticles as model compounds for the actual emitted particles and focus on their fast uptake and association with mitochondria, the cell's powerhouse.