Latent membrane protein 1 and macrophage-derived TNFα synergistically activate and mobilize invadopodia to drive invasion of nasopharyngeal carcinoma.

Invadopodia are actin-rich membrane protrusions that digest the matrix barrier during cancer metastasis. Since the discovery of invadopodia, they have been visualized as localized and dot-like structures in different types of cancer cells on top of a 2D matrix. In this investigation of Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC), a highly invasive cancer frequently accompanied by neck lymph node and distal organ metastases, we revealed a new form of invadopodium with mobilizing features. Integration of live-cell imaging and molecular assays revealed the interaction of macrophage-released TNFα and EBV-encoded latent membrane protein 1 (LMP1) in co-activating the EGFR/Src/ERK/cortactin and Cdc42/N-WASP signaling axes for mobilizing the invadopodia with lateral movements. This phenomenon endows the invadopodia with massive degradative power, visualized as a shift of focal dot-like digestion patterns on a 2D gelatin to a dendrite-like digestion pattern. Notably, single stimulation of either LMP1 or TNFα could only enhance the number of ordinary dot-like invadopodia, suggesting that the EBV infection sensitizes the NPC cells to form mobilizing invadopodia when encountering a TNFα-rich tumor microenvironment. This study unveils the interplay of EBV and stromal components in driving the invasive potential of NPC via unleashing the propulsion of invadopodia in overcoming matrix hurdles. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Artifact-free high-density localization microscopy analysis.

High-density analysis methods for localization microscopy increase acquisition speed but produce artifacts. We demonstrate that these artifacts can be eliminated by the combination of Haar wavelet kernel (HAWK) analysis with standard single-frame fitting. We tested the performance of this method on synthetic, fixed-cell, and live-cell data, and found that HAWK preprocessing yielded reconstructions that reflected the structure of the sample, thus enabling high-speed, artifact-free super-resolution imaging of live cells.

Fungal diversity notes 1387-1511: taxonomic and phylogenetic contributions on genera and species of fungal taxa.

This article is the 13th contribution in the Fungal Diversity Notes series, wherein 125 taxa from four phyla, ten classes, 31 orders, 69 families, 92 genera and three genera incertae sedis are treated, demonstrating worldwide and geographic distribution. Fungal taxa described and illustrated in the present study include three new genera, 69 new species, one new combination, one reference specimen and 51 new records on new hosts and new geographical distributions. Three new genera, Cylindrotorula (Torulaceae), Scolecoleotia (Leotiales genus incertae sedis) and Xenovaginatispora (Lindomycetaceae) are introduced based on distinct phylogenetic lineages and unique morphologies. Newly described species are Aspergillus lannaensis, Cercophora dulciaquae, Cladophialophora aquatica, Coprinellus punjabensis, Cortinarius alutarius, C. mammillatus, C. quercoflocculosus, Coryneum fagi, Cruentomycena uttarakhandina, Cryptocoryneum rosae, Cyathus uniperidiolus, Cylindrotorula indica, Diaporthe chamaeropicola, Didymella azollae, Diplodia alanphillipsii, Dothiora coronicola, Efibula rodriguezarmasiae, Erysiphe salicicola, Fusarium queenslandicum, Geastrum gorgonicum, G. hansagiense, Helicosporium sexualis, Helminthosporium chiangraiensis, Hongkongmyces kokensis, Hydrophilomyces hydraenae, Hygrocybe boertmannii, Hyphoderma australosetigerum, Hyphodontia yunnanensis, Khaleijomyces umikazeana, Laboulbenia divisa, Laboulbenia triarthronis, Laccaria populina, Lactarius pallidozonarius, Lepidosphaeria strobelii, Longipedicellata megafusiformis, Lophiotrema lincangensis, Marasmius benghalensis, M. jinfoshanensis, M. subtropicus, Mariannaea camelliae, Melanographium smilaxii, Microbotryum polycnemoides, Mimeomyces digitatus, Minutisphaera thailandensis, Mortierella solitaria, Mucor harpali, Nigrograna jinghongensis, Odontia huanrenensis, O. parvispina, Paraconiothyrium ajrekarii, Parafuscosporella niloticus, Phaeocytostroma yomensis, Phaeoisaria synnematicus, Phanerochaete hainanensis, Pleopunctum thailandicum, Pleurotheciella dimorphospora, Pseudochaetosphaeronema chiangraiense, Pseudodactylaria albicolonia, Rhexoacrodictys nigrospora, Russula paravioleipes, Scolecoleotia eriocamporesi, Seriascoma honghense, Synandromyces makranczyi, Thyridaria aureobrunnea, Torula lancangjiangensis, Tubeufia longihelicospora, Wicklowia fusiformispora, Xenovaginatispora phichaiensis and Xylaria apiospora. One new combination, Pseudobactrodesmium stilboideus is proposed. A reference specimen of Comoclathris permunda is designated. New host or distribution records are provided for Acrocalymma fici, Aliquandostipite khaoyaiensis, Camarosporidiella laburni, Canalisporium caribense, Chaetoscutula juniperi, Chlorophyllum demangei, C. globosum, C. hortense, Cladophialophora abundans, Dendryphion hydei, Diaporthe foeniculina, D. pseudophoenicicola, D. pyracanthae, Dictyosporium pandanicola, Dyfrolomyces distoseptatus, Ernakulamia tanakae, Eutypa flavovirens, E. lata, Favolus septatus, Fusarium atrovinosum, F. clavum, Helicosporium luteosporum, Hermatomyces nabanheensis, Hermatomyces sphaericoides, Longipedicellata aquatica, Lophiostoma caudata, L. clematidis-vitalbae, Lophiotrema hydei, L. neoarundinaria, Marasmiellus palmivorus, Megacapitula villosa, Micropsalliota globocystis, M. gracilis, Montagnula thailandica, Neohelicosporium irregulare, N. parisporum, Paradictyoarthrinium diffractum, Phaeoisaria aquatica, Poaceascoma taiwanense, Saproamanita manicata, Spegazzinia camelliae, Submersispora variabilis, Thyronectria caudata, T. mackenziei, Tubeufia chiangmaiensis, T. roseohelicospora, Vaginatispora nypae, Wicklowia submersa, Xanthagaricus necopinatus and Xylaria haemorrhoidalis. The data presented herein are based on morphological examination of fresh specimens, coupled with analysis of phylogenetic sequence data to better integrate taxa into appropriate taxonomic ranks and infer their evolutionary relationships.

Publisher Correction: A mechano-signalling network linking microtubules, myosin IIA filaments and integrin-based adhesions.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A mechano-signalling network linking microtubules, myosin IIA filaments and integrin-based adhesions.

The interrelationship between microtubules and the actin cytoskeleton in mechanoregulation of integrin-mediated adhesions is poorly understood. Here, we show that the effects of microtubules on two major types of cell-matrix adhesion, focal adhesions and podosomes, are mediated by KANK family proteins connecting the adhesion protein talin with microtubule tips. Both total microtubule disruption and microtubule uncoupling from adhesions by manipulations with KANKs trigger a massive assembly of myosin IIA filaments, augmenting focal adhesions and disrupting podosomes. Myosin IIA filaments are indispensable effectors in the microtubule-driven regulation of integrin-mediated adhesions. Myosin IIA filament assembly depends on Rho activation by the RhoGEF GEF-H1, which is trapped by microtubules when they are connected with integrin-mediated adhesions via KANK proteins but released after their disconnection. Thus, microtubule capture by integrin-mediated adhesions modulates the GEF-H1-dependent effect of microtubules on the assembly of myosin IIA filaments. Subsequent actomyosin reorganization then remodels the focal adhesions and podosomes, closing the regulatory loop.

The Rényi divergence enables accurate and precise cluster analysis for localization microscopy.

Motivation: Clustering analysis is a key technique for quantitatively characterizing structures in localization microscopy images. To build up accurate information about biological structures, it is critical that the quantification is both accurate (close to the ground truth) and precise (has small scatter and is reproducible). Results: Here, we describe how the Rényi divergence can be used for cluster radius measurements in localization microscopy data. We demonstrate that the Rényi divergence can operate with high levels of background and provides results which are more accurate than Ripley's functions, Voronoi tesselation or DBSCAN. Availability and implementation: The data supporting this research and the software described are accessible at the following site: https://dx.doi.org/10.18742/RDM01-316. Correspondence and requests for materials should be addressed to the corresponding author. Supplementary information: Supplementary data are available at Bioinformatics online.

Investigation of podosome ring protein arrangement using localization microscopy images.

Podosomes are adhesive structures formed on the plasma membrane abutting the extracellular matrix of macrophages, osteoclasts, and dendritic cells. They consist of an f-actin core and a ring structure composed of integrins and integrin-associated proteins. The podosome ring plays a major role in adhesion to the underlying extracellular matrix, but its detailed structure is poorly understood. Recently, it has become possible to study the nano-scale structure of podosome rings using localization microscopy. Unlike traditional microscopy images, localization microscopy images are reconstructed using discrete points, meaning that standard image analysis methods cannot be applied. Here, we present a pipeline for podosome identification, protein position calculation, and creating a podosome ring model for use with localization microscopy data.

Tyrosine phosphorylation of WIP releases bound WASP and impairs podosome assembly in macrophages.

Podosomes are integrin-containing adhesion structures commonly found in migrating leukocytes of the monocytic lineage. The actin cytoskeletal organisation of podosomes is based on a WASP- and Arp2/3-mediated mechanism. WASP also associates with a second protein, WIP (also known as WIPF1), and they co-localise in podosome cores. Here, we report for the first time that WIP can be phosphorylated on tyrosine residues and that tyrosine phosphorylation of WIP is a trigger for release of WASP from the WIP-WASP complex. Using a knockdown approach together with expression of WIP phosphomimics, we show that in the absence of WIP-WASP binding, cellular WASP is rapidly degraded, leading to disruption of podosomes and a failure of cells to degrade an underlying matrix. In the absence of tyrosine phosphorylation, the WIP-WASP complex remains intact and podosome lifetimes are extended. A screen of candidate kinases and inhibitor-based assays identified Bruton's tyrosine kinase (Btk) as a regulator of WIP tyrosine phosphorylation. We conclude that tyrosine phosphorylation of WIP is a crucial regulator of WASP stability and function as an actin-nucleation-promoting factor.

Analgesia for patients undergoing shockwave lithotripsy for urinary stones - a systematic review and meta-analysis.

BACKGROUND: Shock wave lithotripsy (SWL) is the first line treatment modality for a significant proportion of patients with upper urinary tracts stones. Simple analgesics, opioids and non-steroidal anti-inflammatory drugs (NSAIDs) are all suitable agents but the relative efficacy and tolerability of these agents is uncertain. OBJECTIVES: To determine the efficacy of the different types of analgesics used for the control of pain during SWL for urinary stones. MATERIALS AND METHODS: We searched the Cochrane Renal Group's Specialised Register, MEDLINE, EMBASE and also hand-searched reference lists of relevant articles (Figure-1). Randomised controlled trials (RCT's) comparing the use of any opioid, simple analgesic or NSAID during SWL were included. These were compared with themselves, each-other or placebo. We included any route or form of administration (bolus, PCA). We excluded agents that were used for their sedative qualities. Data were extracted and assessed for quality independently by three reviewers. Meta-analyses have been performed where possible. When not possible, descriptive analyses of variables were performed. Dichotomous outcomes are reported as relative risk (RR) and measurements on continuous scales are reported as weighted mean differences (WMD) with 95% confidence intervals. RESULTS: Overall, we included 9 RCTs (539 participants from 6 countries). Trial agents included 7 types of NSAIDs, 1 simple analgesic and 4 types of opioids. There were no significant differences in clinical efficacy or tolerability between a simple analgesic (paracetamol) and an NSAID (lornoxicam). When comparing the same simple analgesic with an opioid (tramadol), both agents provided safe and effective analgesia for the purpose of SWL with no significant differences. There were no significant differences in pain scores between NSAIDs or opioids in three studies. Adequate analgesia could be achieved more often for opioids than for NSAIDs (RR 0.358; 95% CI 043 to 0.77, P=0.0002) but consumed doses of rescue analgesia were similar between NSAIDs and opioids in two studies (P=0.58, >0.05). In terms of tolerability, there is no difference in post-operative nausea and vomiting (PONV) between the groups (RR 0.72, 95% CI 0.24 to 2.17, P=0.55). One study compared outcomes between two types of NSAIDs (diclofenac versus dexketoprofen). There were no significant differences in any of our pre-defined outcomes measures. CONCLUSION: Simple analgesics, NSAIDs and opioids can all reduce the pain associated with shock wave lithotripsy to a level where the procedure is tolerated. Whilst there are no compelling differences in safety or efficacy of simple analgesics and NSAIDs, analgesia is described as adequate more often for opioids than NSAIDs.

ß1 integrins regulate fibroblast chemotaxis through control of N-WASP stability.

Chemotactic migration of fibroblasts towards growth factors, such as during development and wound healing, requires precise spatial coordination of receptor signalling. However, the mechanisms regulating this remain poorly understood. Here, we demonstrate that ß1 integrins are required both for fibroblast chemotaxis towards platelet-derived growth factor (PDGF) and growth factor-induced dorsal ruffling. Mechanistically, we show that ß1 integrin stabilises and spatially regulates the actin nucleating endocytic protein neuronal Wiskott­Aldrich syndrome protein (N-WASP) to facilitate PDGF receptor traffic and directed motility. Furthermore, we show that in intact cells, PDGF binding leads to rapid activation of ß1 integrin within newly assembled actin-rich membrane ruffles. Active ß1 in turn controls assembly of N-WASP complexes with both Cdc42 and WASP-interacting protein (WIP), the latter of which acts to stabilise the N-WASP. Both of these protein complexes are required for PDGF internalisation and fibroblast chemotaxis downstream of ß1 integrins. This represents a novel mechanism by which integrins cooperate with growth factor receptors to promote localised signalling and directed cell motility.

Megakaryocytes assemble podosomes that degrade matrix and protrude through basement membrane.

Megakaryocytes give rise to platelets via extension of proplatelet arms, which are released through the vascular sinusoids into the bloodstream. Megakaryocytes and their precursors undergo varying interactions with the extracellular environment in the bone marrow during their maturation and positioning in the vascular niche. We demonstrate that podosomes are abundant in primary murine megakaryocytes adherent on multiple extracellular matrix substrates, including native basement membrane. Megakaryocyte podosome lifetime and density, but not podosome size, are dependent on the type of matrix, with podosome lifetime dramatically increased on collagen fibers compared with fibrinogen. Podosome stability and dynamics depend on actin cytoskeletal dynamics but not matrix metalloproteases. However, podosomes degrade matrix and appear to be important for megakaryocytes to extend protrusions across a native basement membrane. We thus demonstrate for the first time a fundamental requirement for podosomes in megakaryocyte process extension across a basement membrane, and our results suggest that podosomes may have a role in proplatelet arm extension or penetration of basement membrane.

Bayesian localization microscopy reveals nanoscale podosome dynamics.

We describe a localization microscopy analysis method that is able to extract results in live cells using standard fluorescent proteins and xenon arc lamp illumination. Our Bayesian analysis of the blinking and bleaching (3B analysis) method models the entire dataset simultaneously as being generated by a number of fluorophores that may or may not be emitting light at any given time. The resulting technique allows many overlapping fluorophores in each frame and unifies the analysis of the localization from blinking and bleaching events. By modeling the entire dataset, we were able to use each reappearance of a fluorophore to improve the localization accuracy. The high performance of this technique allowed us to reveal the nanoscale dynamics of podosome formation and dissociation throughout an entire cell with a resolution of 50 nm on a 4-s timescale.

Focal adhesion kinase controls actin assembly via a FERM-mediated interaction with the Arp2/3 complex.

Networks of actin filaments, controlled by the Arp2/3 complex, drive membrane protrusion during cell migration. How integrins signal to the Arp2/3 complex is not well understood. Here, we show that focal adhesion kinase (FAK) and the Arp2/3 complex associate and colocalize at transient structures formed early after adhesion. Nascent lamellipodia, which originate at these structures, do not form in FAK-deficient cells, or in cells in which FAK mutants cannot be autophosphorylated after integrin engagement. The FERM domain of FAK binds directly to Arp3 and can enhance Arp2/3-dependent actin polymerization. Critically, Arp2/3 is not bound when FAK is phosphorylated on Tyr 397. Interfering peptides and FERM-domain point mutants show that FAK binding to Arp2/3 controls protrusive lamellipodia formation and cell spreading. This establishes a new function for the FAK FERM domain in forming a phosphorylation-regulated complex with Arp2/3, linking integrin signalling directly with the actin polymerization machinery.

Unregulated actin polymerization by WASp causes defects of mitosis and cytokinesis in X-linked neutropenia.

Specific mutations in the human gene encoding the Wiskott-Aldrich syndrome protein (WASp) that compromise normal auto-inhibition of WASp result in unregulated activation of the actin-related protein 2/3 complex and increased actin polymerizing activity. These activating mutations are associated with an X-linked form of neutropenia with an intrinsic failure of myelopoiesis and an increase in the incidence of cytogenetic abnormalities. To study the underlying mechanisms, active mutant WASp(I294T) was expressed by gene transfer. This caused enhanced and delocalized actin polymerization throughout the cell, decreased proliferation, and increased apoptosis. Cells became binucleated, suggesting a failure of cytokinesis, and micronuclei were formed, indicative of genomic instability. Live cell imaging demonstrated a delay in mitosis from prometaphase to anaphase and confirmed that multinucleation was a result of aborted cytokinesis. During mitosis, filamentous actin was abnormally localized around the spindle and chromosomes throughout their alignment and separation, and it accumulated within the cleavage furrow around the spindle midzone. These findings reveal a novel mechanism for inhibition of myelopoiesis through defective mitosis and cytokinesis due to hyperactivation and mislocalization of actin polymerization.

Moving matters: signals and mechanisms in directed cell migration.

The EMBO workshop on Cell Migration, held in Heidelberg this May, highlighted new trends in cell migration research, as well as the need to reassess current dogma. Key insights included altered ideas for the roles of Rac and inositol lipids, for the ways that groups of cells coordinate their migration and for the importance of considering movement from both a cell biological and mechanical perspective.

PAK4: a pluripotent kinase that regulates prostate cancer cell adhesion.

Hepatocyte growth factor (HGF) is associated with tumour progression and increases the invasiveness of prostate carcinoma cells. Migration and invasion require coordinated reorganisation of the actin cytoskeleton and regulation of cell-adhesion dynamics. Rho-family GTPases orchestrate both of these cellular processes. p21-activated kinase 4 (PAK4), a specific effector of the Rho GTPase Cdc42, is activated by HGF, and we have previously shown that activated PAK4 induces a loss of both actin stress fibres and focal adhesions. We now report that DU145 human prostate cancer cells with reduced levels of PAK4 expression are unable to successfully migrate in response to HGF, have prominent actin stress fibres, and an increase in the size and number of focal adhesions. Moreover, these cells have a concomitant reduction in cell-adhesion turnover rates. We find that PAK4 is localised at focal adhesions, is immunoprecipitated with paxillin and phosphorylates paxillin on serine 272. Furthermore, we demonstrate that PAK4 can regulate RhoA activity via GEF-H1. Our results suggest that PAK4 is a pluripotent kinase that can regulate both actin cytoskeletal rearrangement and focal-adhesion dynamics.

Tyrosine phosphorylation of WASP promotes calpain-mediated podosome disassembly.

Podosomes are actin-based adhesions involved in migration of cells that have to cross tissue boundaries such as myeloid cells. The Wiskott Aldrich Syndrome Protein regulates de novo actin polymerization during podosome formation and it is cleaved by the protease calpain during podosome disassembly. The mechanisms that may induce the Wiskott Aldrich Syndrome Protein cleavage by calpain remain undetermined. We now report that in myeloid cells, tyrosine phosphorylation of the Wiskott Aldrich Syndrome Protein-tyrosine291 (Human)/tyrosine293 (mouse) not only enhances Wiskott Aldrich Syndrome Protein-mediated actin polymerization but also promotes its calpain-dependent degradation during podosome disassembly. We also show that activation of the Wiskott Aldrich Syndrome Protein leading to podosome formation occurs independently of tyrosine phosphorylation in spleen-derived dendritic cells. We conclude that tyrosine phosphorylation of the Wiskott Aldrich Syndrome Protein integrates dynamics of actin and cell adhesion proteins during podosome disassembly required for mobilization of myeloid cells during the immune response.

Phosphorylation of WASp is a key regulator of activity and stability in vivo.

The Wiskott-Aldrich syndrome protein (WASp) is a key cytoskeletal regulator in hematopoietic cells. Covalent modification of a conserved tyrosine by phosphorylation has emerged as an important potential determinant of activity, although the physiological significance remains uncertain. In a murine knockin model, mutation resulting in inability to phosphorylate Y293 (Y293F) mimicked many features of complete WASp-deficiency. Although a phosphomimicking mutant Y293E conferred enhanced actin-polymerization, the cellular phenotype was similar due to functional dysregulation. Furthermore, steady-state levels of Y293E-WASp were markedly reduced compared to wild-type WASp and Y293F-WASp, although partially recoverable by treatment of cells with proteasome inhibitors. Consequently, tyrosine phosphorylation plays a critical role in normal activation of WASp in vivo, and is indispensible for multiple tasks including proliferation, phagocytosis, chemotaxis, and assembly of adhesion structures. Furthermore, it may target WASp for proteasome-mediated degradation, thereby providing a default mechanism for self-limiting stimulation of the Arp2/3 complex.

Pressure and stiffness sensing together regulate vascular smooth muscle cell phenotype switching.

Vascular smooth muscle cells (VSMCs) play a central role in the progression of atherosclerosis, where they switch from a contractile to a synthetic phenotype. Because of their role as risk factors for atherosclerosis, we sought here to systematically study the impact of matrix stiffness and (hemodynamic) pressure on VSMCs. Thereby, we find that pressure and stiffness individually affect the VSMC phenotype. However, only the combination of hypertensive pressure and matrix compliance, and as such mechanical stimuli that are prevalent during atherosclerosis, leads to a full phenotypic switch including the formation of matrix-degrading podosomes. We further analyze the molecular mechanism in stiffness and pressure sensing and identify a regulation through different but overlapping pathways culminating in the regulation of the actin cytoskeleton through cofilin. Together, our data show how different pathological mechanical signals combined but through distinct pathways accelerate a phenotypic switch that will ultimately contribute to atherosclerotic disease progression.