Epithelial Cell Motility Research Articles

Borg5/Cdc42EP1 restricts contractility and motility in epithelial MDCK cells.

The Borg/Cdc42EP family comprises septin binding proteins, which are known to promote septin-dependent stress fibers and acto-myosin contractility. We show here that epithelial Borg5/Cdc42ep1 instead limits contractility, cell-cell adhesion tension and motility as is required for the acquisition of columnar, isotropic cell morphology in mature MDCK monolayers. Borg5 depletion inhibited the development of the lateral F-actin cortex, stimulated microtubule-dependent leading-edge lamellae as well as radial stress fibers and, independently of the basal F-actin phenotype, caused anisotropy of apical surfaces within compacted monolayers. We determined that Borg5 limits septin-colocalization with microtubules, and that like Septin 2, Borg5 interacts with the rod-domain of Myosin- IIA. The interaction of Myosin-IIA with Borg5 was reduced in the presence of septins. Because septins also mediate myosin activation, we propose that Borg5 limits contractility in MDCK cells in part by counteracting septin-associated myosin activity.

Retraction: vitexin attenuates epithelial ovarian cancer cell viability and motility in vitro and carcinogenesis in vivo via p38 and ERK1/2 pathways related VEGFA.

[This retracts the article DOI: 10.21037/atm-20-5586.].

Development of a multi-analysis model using an epithelial-fibroblast co-culture system as an alternative to animal testing

The evaluation of respiratory chemical substances has been mostly performed in animal tests (OECD TG 403, TG 412, TG 413, etc.). However, there have been ongoing discussions about the limited use of these inhalation toxicity tests due to differences in the anatomical structure of the respiratory tract, difficulty in exposure, laborious processes, and ethical reasons. Alternative animal testing methods that mimic in vivo testing are required. Therefore, in this study, we established a co-culture system composed of differentiated epithelial cells under an air-liquid interface (ALI) system in the apical part and fibroblasts in the basal part. This system was designed to mimic the wound-healing mechanism in the respiratory system. In addition, we developed a multi-analysis system that simultaneously performs toxicological and functional evaluations. Several individual assays were used sequentially in a multi-analysis model for pulmonary toxicity. Briefly, cytokine analysis, histology, and cilia motility were measured in the apical part, and cell migration and gel contraction assay were performed by exposing MRC-5 cells to the basal culture. First, human airway epithelial cells from bronchial (hAECB) were cultured under air-liquid interface (ALI) system conditions and validated pseudostratified epithelium by detecting differentiation-related epithelial markers using Transepithelial Electrical Resistance (TEER) measurement, Hematoxylin and Eosin (H&E) staining, and immunocytochemistry (ICC) staining. Afterward, the co-culture cells exposed to Transforming growth factor-beta 1 (TGF-β1), a key mediator of pulmonary fibrosis, induced significant toxicological responses such as cytotoxicity, cell migration, and gel contraction, which are wound-healing markers. In addition, cilia motility in epithelial cells was significantly decreased compared to control. Therefore, the multi-analysis model with a 3D epithelial-fibroblast co-culture system is expected to be useful in predicting pulmonary toxicity as a simple and efficient high-throughput screening method and as an alternative to animal testing.

Abstract 6849: Characterizing a discernible stromal fibroblastic gene signature in the shift from high-grade prostatic intraepithelial neoplasia to aggressive prostate cancer

Abstract Background: High-grade prostatic intraepithelial neoplasia (HGPIN) is a preneoplastic lesion that precedes the development of both indolent and aggressive variants of prostate cancer (PCa). However, the specific stromal molecular mechanisms underlying the progression of HGPIN and their contribution to epithelial cancer cell motility and invasiveness remain poorly understood. This study aims to elucidate the driver genomic alterations involved in shaping the perineoplastic stroma of HGPIN, with the goal of unraveling their role in promoting cancer invasion, and metastasis. Methods: We performed gene expression profiling on laser capture microdissected perineoplastic stroma of HGPIN and PCa in tissue samples from 25 PCa cases, including 12 low-grade (Gleason 6) and 13 high-grade (Gleason >/= 8) cases. We used the standard moderated t-test from the Bioconductor limma package to assess the statistical significance of differential gene expression between perineoplastic stroma high grade PCa and perineoplastic stroma HGPIN, as well as between perineoplastic stroma low grade PCa and HGPIN. The -log10 p-values represents the level of statistical significance for each gene, while the log2 fold change represents the magnitude of gene expression difference between the two comparison groups. Additionally, we computed Gene Set Enrichment Analysis (GSEA) scores using the Bioconductor package and discerned the leading-edge genes among the pathways. This study is supported by the NIH-NCI-T32 program for next-generation pathologists at our institution. Results: In the gene expression analysis comparing High Grade PCa and HGPIN, several genes, including POSTN, BGN, GREM1, C1QA, THBS4, COL1A1, COL1A2, SFRP4, RNU6-847P, FCGR2P, and TOMM22, exhibited the highest level of both biological and statistical significance. GSEA revealed that the multi-invasive pathway had the highest enrichment score (>2). Notably, the top overexpressed genes in this pathway exhibited a fibroblastic signature (in bold), including POSTN, BGN, GREM1, FBN1, COL1A2, COL3A1, COL5A2, ASPN, SPARC, VCAN, COMP, INHBA, THBS2, and SFRP4. The presence of this signature indicates the invasiveness of the disease. Importantly, these genes were not associated with the progression to low grade PCa, indicating their exclusive association with the aggressive variant. Conclusion: To our knowledge, this study is the first to explore the stroma's role in HGPIN-to-aggressive PCa progression. It highlights a key stromal pathway enriched with fibroblastic gene signature. These findings offer potential biomarkers for targeted therapies and improved care through HGPIN patient stratification. Citation Format: Mohammad K. Alexanderani, Lucio Queiroz, Mohamed Omar, Claudio Zanettini, Hubert Pakula, Luigi Marchionni, Massimo Loda. Characterizing a discernible stromal fibroblastic gene signature in the shift from high-grade prostatic intraepithelial neoplasia to aggressive prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6849.

Reduced chemokine C-C motif ligand 1 expression may negatively regulate colorectal cancer progression at liver metastatic sites.

Colorectal cancer (CRC) liver metastasis, albeit a stage-IV disease, is completely curable by surgical resection in selected patients. In addressing the molecular basics of this phenomenon, differentially expressed genes at primary and liver metastatic sites were screened by RNA sequencing with the use of paraffin-embedded surgical specimens. Chemokine C-C motif ligand 1 (CCL1), a chemotactic factor for a ligand of the chemokine C-C motif receptor 8 (CCR8), was isolated as one of the differentially expressed genes. Histological analysis revealed that the number of CCL1-positive cells, mainly tumour associated macrophages (TAMs) located in the stroma of CRC, decreased significantly at liver metastatic sites, while the expression level of CCR8 on CRC remained unchanged. To explore the biological significance of the CCL1-CCR8 axis in CRC, CCR8-positive CRC cell line Colo320DM was used to assess the effect of the CCL1-CCR8 axis on major signalling pathways, epithelial mesenchymal transition induction and cell motility. Upon stimulation of recombinant CCL1 (rCCL1), phosphorylation of AKT was observed in Colo320DM cells; on the other hand, the corresponding significant increase in MMP-2 levels demonstrated by RT-qPCR was nullified by siRNA (siCCR8). In the scratch test, rCCL1 treatment significantly increased the motility of Colo320DM cells, which was similarly nullified by siCCR8. Thus, the activation of the CCL1-CCR8 axis is a positive regulator of CRC tumour progression. Reduced CCL1 expression of TAMs at liver metastatic sites may partly explain the unique slow tumour progression of CRC, thus providing for a grace period for radical resection of metastatic lesions.

Sir Michael George Parke Stoker. 4 July 1918—13 August 2013

Michael Stoker was a renowned virologist and cell biologist. He gained his interest in research while serving as a medical officer during the Second World War in India, studying infectious diseases such as typhus. He began to study viruses in the Department of Pathology in Cambridge and in 1958 was appointed to the first established UK chair of virology and as head of the Medical Research Council Virus Unit at the University of Glasgow. He pioneered studies of cancer-causing viruses using polyomavirus of mice, and developed the baby hamster kidney cell lines still used today for vaccine production. In 1968 he moved to London as director of research at the Imperial Cancer Research Fund (ICRF) Laboratories, now part of the Cancer Research UK funded laboratories at the Francis Crick Institute. He brought many virologists to ICRF, while he himself turned to cell biology, first of mesenchymal cells and then of normal and malignant epithelial cells, particularly breast epithelium. Returning to Cambridge in 1978, he discovered scatter factor (also known as hepatocyte growth factor), a paracrine cytokine that stimulates motility and proliferation of epithelial cells. Michael had broad-ranging interests and there are few virologists in the UK who have not been influenced either by him directly or by his protégés. Among the many activities beyond the institutions where he worked, he served from 1976 to 1981 as Foreign Secretary and Vice-President of the Royal Society.

Nano Self-Assemblies of Caffeic Acid-Fibronectin Mimic a Peptide Conjugate for the Treatment of Corneal Epithelial Injury.

Rapid corneal re-epithelialization is important for corneal wound healing. Corneal epithelial cell motility and oxidative stress are important targets for therapeutic intervention. In this study, we covalently conjugated the antioxidant caffeic acid (CA) with a bioactive peptide sequence (PHSRN) to generate a CA-PHSRN amphiphile, which was formulated into nanoparticular eye drops with an average size of 43.21 ± 16 nm. CA-PHSRN caused minimal cytotoxicity against human corneal epithelial cells (HCECs) and RAW264.7 cells, exhibited an excellent free radical scavenging ability, and remarkably attenuated reactive oxygen species (ROS) levels in H2O2-stimulated HCECs. The antioxidant and anti-inflammatory activities of CA-PHSRN were assessed in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results show that CA-PHSRN treatment effectively prevented LPS-induced DNA damage and significantly reduced the levels of LPS-induced pro-inflammatory cytochemokines (i.e., iNOS, NO, TNF-α, IL-6, and COX-2) in a dose-dependent manner. Moreover, using a rabbit corneal epithelial ex vivo migration assay, we demonstrated that the proposed CA-PHSRN accelerated corneal epithelial cell migration and exhibited high ocular tolerance and ocular bioavailability after topical instillation. Taken together, the proposed CA-PHSRN nanoparticular eye drops are a promising therapeutic formulation for the treatment of corneal epithelial injury.

Abstract 5817: LKB1 overcomes RAS pathway-mediated loss of epithelial integrity

Abstract Oncogenic RAS pathway disassembles cell-cell and cell-basement membrane junctions, thus promoting epithelial cell motility and invasion. To find tumor proteomic changes responsible for the disrupting effects of RAS on epithelial integrity, we explored cBioportal cell line proteomics data across all cancer types for correlations between oncogenic KRAS or HRAS mutations and possible regulators of epithelial integrity. We found inverse correlation between these RAS mutations and tumor suppressor LKB1 protein levels in a cohort where LKB1 was not inactivated by a mutation. Furthermore, LKB1 protein levels were also positively correlated with NF2 protein (a negative regulator of RAS) in human breast tumors and inversely correlated with c-RAF (RAS effector) activating phosphorylation at serine 338 in breast cancer cell lines. We sought to functionally clarify the relationship between RAS pathway and LKB1, finding that an ectopic constitutive or inducible expression of HRASV12 downregulates LKB1 protein in mammary epithelial MCF10A cells and HMEC-hTERT cells. Furthermore, RAS-mutant MCF10A cells regained LKB1 protein levels upon treatment with MEK/ERK inhibitors. We establish that the RAS-mediated downregulation of LKB1 protein occurs through proteasomal activity. LKB1 reconstituted MCF10A-HRASV12 (RAS-LKB1) cells displayed restored desmoplakin, γ-catenin and E-cadherin pericellular immunostaining pattern in monolayer cultures, suggesting restoration of desmosomes and adherence junctions. We also cultured RAS-LKB1 cells in 3D egg-white and observe restoration of E-cadherin, γ-catenin, α6-integrin, and laminin-332, indicating a rescue of epithelial integrity in 3D context. Our findings suggest that LKB1 rescues mutant RAS-mediated disruption of cell-cell and cell-basement membrane junctions and general epithelial integrity. Our current aim is to define how LKB1 suppresses RAS mediated disruption of breast epithelial integrity, that is expected to shed new light into early stages of tumor invasion and uncover novel therapeutic opportunities via restoration of LKB1. Citation Format: Topi A. Tervonen, Shishir M. Pant, Johanna Englund, Juha Klefström. LKB1 overcomes RAS pathway-mediated loss of epithelial integrity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5817.

CD300b regulates intestinal inflammation and promotes repair in colitis.

Chronic inflammation is a hallmark charataristic of various inflammatory diseases including inflammatory bowel disease. Subsequently, current therapeutic approaches target immune-mediated pathways as means for therapeutic intervention and promotion of mucosal healing and repair. Emerging data demonstrate important roles for CD300 receptor family members in settings of innate immunity as well as in allergic and autoimmune diseases. One of the main pathways mediating the activities of CD300 family members is via promotion of resolution through interactions with ligands expressed by viruses, bacteria, or dead cells (e.g., phospholipids such as PtdSer and/or ceramide). We have recently shown that the expression of CD300a, CD300b and CD300f were elevated in patients with IBD and that CD300f (but not CD300a) regulates colonic inflammation in response to dextran sodium sulphate (DSS)-induced colitis. Whether CD300b has a role in colitis or mucosal healing is largely unknown. Herein, we demonstrate a central and distinct role for CD300b in colonic inflammation and subsequent repair. We show that Cd300b-/- mice display defects in mucosal healing upon cessation of DSS treatment. Cd300b-/- mice display increased weight loss and disease activity index, which is accompanied by increased colonic histopathology, increased infiltration of inflammatory cells and expression of multiple pro-inflammatory upon cessation of DSS cytokines. Furthermore, we demonstrate that soluble CD300b (sCD300b) is increased in the colons of DSS-treated mice and establish that CD300b can bind mouse and human epithelial cells. Finally, we show that CD300b decreases epithelial EpCAM expression, promotes epithelial cell motility and wound healing. These data highlight a key role for CD300b in colonic inflammation and repair processes and suggest that CD300b may be a future therapeutic target in inflammatory GI diseases.

Phthalides Isolated from the Endolichenic Arthrinium sp. EL000127 Exhibits Antiangiogenic Activity.

Endolichenic fungi (ELF) produce specialized metabolites that have various medicinal properties. Inhibition of tumor angiogenesis efficaciously suppresses many types of cancer. This study aimed to discover novel antiangiogenic agents from specialized metabolite extracts of ELF strains isolated from Korean lichens. The EtOAc extracts of 51 ELF strains were subjected to a screening pipeline consisting of cell viability, scratch wound healing, and Transwell migration assays. The EtOAc extract of Arthrinium sp. EL000127 showed the most potent inhibitory activity against the chemotactic migration of human umbilical vein endothelial cells (HUVEC). Targeted isolation on the major LC-MS peaks exhibited a previously known phthalide, 3-O-methylcyclopolic acid (1), and two unknown analogues of 1, 3-O-phenylethylcyclopolic acid (2) and 3-O-p-hydroxyphenylethylcyclopolic acid (3). The structures were characterized by MS and NMR analyses. All the isolates were acquired and applied to bioassays as racemates due to spontaneous racemization. Among the isolates, compound 3 effectively inhibits HUVEC motility by suppressing mRNA expressions of genes regulating epithelial cell survival and motility, which suggested that compound 3 is a potent antiangiogenic agent suitable for further exploration as a potential novel therapeutic against cancers.

Opportunities and Challenges for the Development of MRCK Kinases Inhibitors as Potential Cancer Chemotherapeutics.

Cytoskeleton organization and dynamics are rapidly regulated by post-translational modifications of key target proteins. Acting downstream of the Cdc42 GTPase, the myotonic dystrophy-related Cdc42-binding kinases MRCKα, MRCKβ, and MRCKγ have recently emerged as important players in cytoskeleton regulation through the phosphorylation of proteins such as the regulatory myosin light chain proteins. Compared with the closely related Rho-associated coiled-coil kinases 1 and 2 (ROCK1 and ROCK2), the contributions of the MRCK kinases are less well characterized, one reason for this being that the discovery of potent and selective MRCK pharmacological inhibitors occurred many years after the discovery of ROCK inhibitors. The disclosure of inhibitors, such as BDP5290 and BDP9066, that have marked selectivity for MRCK over ROCK, as well as the dual ROCK + MRCK inhibitor DJ4, has expanded the repertoire of chemical biology tools to study MRCK function in normal and pathological conditions. Recent research has used these novel inhibitors to establish the role of MRCK signalling in epithelial polarization, phagocytosis, cytoskeleton organization, cell motility, and cancer cell invasiveness. Furthermore, pharmacological MRCK inhibition has been shown to elicit therapeutically beneficial effects in cell-based and in vivo studies of glioma, skin, and ovarian cancers.

Surface activity of cancer cells: The fusion of two cell aggregates

A key feature that distinguishes cancer cells from all other cells is their capability to spread throughout the body. Although how cancer cells collectively migrate by following molecular rules which influence the state of cell-cell adhesion contacts has been comprehensively formulated, the impact of physical interactions on cell spreading remains less understood. Cumulative effects of physical interactions exist as the interplay between various physical parameters such as (1) tissue surface tension, (2) viscoelasticity caused by collective cell migration, and (3) solid stress accumulated in the cell aggregate core region. This review aims to point out the role of these physical parameters in cancer cell spreading by considering and comparing the rearrangement of various mono-cultured cancer and epithelial model systems such as the fusion of two cell aggregates. While epithelial cells undergo volumetric cell rearrangement driven by the tissue surface tension, which directs cell movement from the surface to the core region of two-aggregate systems, cancer cells rather perform surface cell rearrangement. Cancer cells migrate toward the surface of the two-aggregate system driven by the solid stress while the surface tension is significantly reduced. The solid stress, accumulated in the core region of the two-aggregate system, is capable of suppressing the movement of epithelial cells that can undergo the jamming state transition; however, this stress enhances the movement of cancer cells. We have focused here on the multi-scale rheological modeling approaches that aimed at reproducing and understanding these biological systems.

Live imaging of delamination in Drosophila shows epithelial cell motility and invasiveness are independently regulated

Delaminating cells undergo complex, precisely regulated changes in cell–cell adhesion, motility, polarity, invasiveness, and other cellular properties. Delamination occurs during development and in pathogenic conditions such as cancer metastasis. We analyzed the requirements for epithelial delamination in Drosophila ovary border cells, which detach from the structured epithelial layer and begin to migrate collectively. We used live imaging to examine cellular dynamics, particularly epithelial cells’ acquisition of motility and invasiveness, in delamination-defective mutants during the time period in which delamination occurs in the wild-type ovary. We found that border cells in slow border cells (slbo), a delamination-defective mutant, lacked invasive cellular protrusions but acquired basic cellular motility, while JAK/STAT-inhibited border cells lost both invasiveness and motility. Our results indicate that invasiveness and motility, which are cooperatively required for delamination, are regulated independently. Our reconstruction experiments also showed that motility is not a prerequisite for acquiring invasiveness.

In Situ Visualization of Dynamic Cellular Effects of Phospholipid Nanoparticles via High-Speed Scanning Ion Conductance Microscopy.

Phospholipid nanoparticles have been actively employed for numerous biomedical applications. A key factor in ensuring effective and safe applications of these nanomaterials is the regulation of their interactions with target cells, which is significantly dependent on an in-depth understanding of the nanoparticle-cell interactions. To date, most studies investigating these nano-bio interactions have been performed under static conditions and may lack crucial real-time information. It is, however, noteworthy that the nanoparticle-cell interactions are highly dynamic. Consequently, to gain a deeper insight into the cellular effects of phospholipid nanoparticles, real-time observation of cellular dynamics after nanoparticle introduction is necessary. Herein, a proof-of-concept in situ visualization of the dynamic cellular effects of sub-100nm phospholipid nanoparticles using high-speed scanning ion conductance microscopy (HS-SICM) is reported. It is revealed that upon introduction into the cellular environment, within a short timescale of hundreds of seconds, phospholipid nanoparticles can selectively modulate the edge motility and surface roughness of healthy fibroblast and cancerous epithelial cells. Furthermore, the dynamic deformation profiles of these cells can be selectively altered in the presence of phospholipid nanoparticles. This work is anticipated to further shed light on the real-time nanoparticle-cell interactions for improved formulation of phospholipid nanoparticles for numerous bioapplications.

Decreased junctional adhesion molecule 3 expression induces reactive oxygen species production and apoptosis in trophoblasts†.

Junctional adhesion molecule 3 (JAM3) is involved in epithelial cell junction, cell polarity, and motility. The molecular mechanisms underlying the role of JAM3 in placental dysfunction remain unclear. We hypothesized that JAM3 expression regulates trophoblast fusion, differentiation, proliferation, and apoptosis. Our results revealed that JAM3 was expressed in the cytotrophoblasts and syncytiotrophoblasts of first-trimester and term placental villi. JAM3 expression in cell-cell junctions decreased with the formation of syncytiotrophoblasts. Using trophoblasts as an in vitro model, we observed that forskolin and JAM3 knockdown significantly reduced JAM3 expression and increased syncytium formation. JAM3 knockdown additionally inhibited trophoblast proliferation and increased the number of trophoblasts in the sub-G1 and G2/M phases, indicating cell-cycle disturbance and apoptosis. Cell-cycle arrest was associated with the engagement of checkpoint kinase 2-cell division cycle 25C-cyclin-dependent kinase 1/cyclin B1 signaling. Increased expression of BIM, NOXA, XAF1, cytochrome c, and cleaved caspase-3 further indicated trophoblast apoptosis. Overexpression of JAM3 or recombinant JAM3 protein enhanced trophoblast adhesion and migration, which were inhibited by JAM3 knockdown. JAM3 knockdown induced reactive oxygen species and syncytin 2 expression in trophoblasts. Furthermore, H2O2-induced oxidative stress reduced JAM3 expression in trophoblasts and cell culture supernatants. H2O2 simultaneously induced trophoblast apoptosis. JAM3 expression was significantly decreased in the plasmas and placentas of patients with early-onset severe preeclampsia. Thus, our results show that JAM3 may not only be a structural component of trophoblast cell junctions but also regulates trophoblast fusion, differentiation, proliferation, apoptosis, and motility. Dysregulated trophoblast JAM3 expression is crucial in preeclampsia development.

Integrated Stress Response Regulation of Corneal Epithelial Cell Motility and Cytokine Production.

PurposeTo investigate the effect of an active integrated stress response (ISR) on human corneal epithelial cell motility and cytokine production.MethodsISR agonists tunicamycin (TUN) and SAL003 (SAL) were used to stimulate the ISR in immortalized corneal epithelial cell lines, primary human limbal epithelial stem cells, and ex vivo human corneas. Reporter lines for ISR-associated transcription factors activating transcription factor 4 (ATF4) and XBP1 activity were generated to visualize pathway activity in response to kinase-specific agonists. Scratch assays and multiplex magnetic bead arrays were used to investigate the effects of an active ISR on scratch wounds and cytokine production. A C/EBP homologous protein (CHOP) knockout cell line was generated to investigate the effects of ISR ablation. Finally, an ISR antagonist was assayed for its ability to rescue negative phenotypic changes associated with an active ISR.ResultsISR stimulation, mediated through CHOP, inhibited cell motility in both immortalized and primary human limbal epithelial cells. Scratch wounding of ex vivo corneas elicited an increase in the ISR mediators phosphorylated-eIF2α and ATF4. ISR stimulation also increased the production of vascular endothelial growth factor (VEGF) and proinflammatory cytokines. ISR ablation, through CHOP knockout or inhibition with integrated stress response inhibitor (ISRIB) rescued epithelia migration ability and reduced VEGF secretion.ConclusionsWe demonstrate that the ISR has dramatic effects on the ability of corneal epithelial cells to respond to wounding models and increases the production of proinflammatory and angiogenic factors. Inhibition of the ISR may provide a new therapeutic option for corneal diseases in which the ISR is implicated.

2021 winner: Lee Dolat

We are pleased to announce that the winner of the 2021 JCS Prize is Lee Dolat for his paper entitled ‘An endometrial organoid model of interactions between Chlamydia and epithelial and immune cells’ (Dolat and Valdivia, 2021).The prize of £1000 is awarded annually to the first author of the paper that is judged by the Editors to be the best eligible paper published in the Journal of Cell Science that year. To be considered for the prize, the first author must be a student or a postdoc of no more than five years standing.Lee grew up in Ledyard, Connecticut, and received his undergraduate degree from the University of Connecticut. After graduation, he worked as a research technician at 454 Life Sciences, a small biotech that was an early developer of next-generation DNA sequencing. He then moved to Boston, MA, where he worked as a research technician at Massachusetts General Hospital under the guidance of Dr Mason Freeman and Dr Michael Fitzgerald. Using stratified epidermal keratinocyte organotypic culture systems, he studied the role of the lipid transporter ABCA12 in epidermal lipid homeostasis and barrier function.For his graduate studies at Drexel University in Philadelphia, PA, Lee joined the laboratory of Dr Elias Spiliotis, whose research focuses on the cell biology of septins, filamentous GTPases that regulate the organization and dynamics of actin, microtubules and cell membranes. In his thesis work, he identified that septins directly bind and bundle actin filaments to regulate the assembly of a contractile stress fiber network, focal adhesion assembly and epithelial cell motility (Dolat et al., 2014; Smith et al., 2015). In a second study, he uncovered a role for septins in macropinocytosis, during which they assemble at contact sites between macropinosomes and endolysosomes in a phosphatidylinositol-specific manner to promote membrane fusion (Dolat and Spiliotis, 2016).Septins were shown by others to participate in cell autonomous immunity to intracellular pathogens, which inspired Lee to undertake a post-doc in the field of host–pathogen interactions. He then joined the laboratory of Dr Raphael Valdivia – an expert in the molecular genetics and cell biology of Chlamydia trachomatis infections at Duke University, Durham, North Carolina, USA. Chlamydia are obligate intracellular pathogens that employ an arsenal of secreted effector proteins to enter host epithelial cells and replicate within a membrane-bound vacuole, termed the inclusion. Owing to its unique intracellular lifecycle, however, Chlamydia has, until the past decade or so, been difficult to genetically manipulate.His research now leverages new techniques to genetically modify Chlamydia, and polarized 2D and 3D epithelial infection models to identify how Chlamydia effector proteins reprogramme epithelial organization, cytoskeletal function and innate immune responses (Dolat and Valdivia, 2021).

The Emerging Role of c-Met in Carcinogenesis and Clinical Implications as a Possible Therapeutic Target.

Background c-MET is a receptor tyrosine kinase receptor (RTK) for the hepatocyte growth factor (HGF). The binding of HGF to c-MET regulates several cellular functions: differentiation, proliferation, epithelial cell motility, angiogenesis, and epithelial-mesenchymal transition (EMT). Moreover, it is known to be involved in carcinogenesis. Comprehension of HGF-c-MET signaling pathway might have important clinical consequences allowing to predict prognosis, response to treatment, and survival rates based on its expression and dysregulation. Discussion. c-MET represents a useful molecular target for novel engineered drugs. Several clinical trials are underway for various solid tumors and the development of new specific monoclonal antibodies depends on the recent knowledge about the definite c-MET role in each different malignance. Recent clinical trials based on c-MET molecular targets result in good safety profile and represent a promising therapeutic strategy for solid cancers, in monotherapy or in combination with other target drugs. Conclusion The list of cell surface receptors crosslinking with the c-MET signaling is constantly growing, highlighting the importance of this pathway for personalized target therapy. Research on the combination of c-MET inhibitors with other drugs will hopefully lead to discovery of new effective treatment options.

Cell Adhesion and Migration on Thickness Gradient Bilayer Polymer Brush Surfaces: Effects of Properties of Polymeric Materials of the Underlayer.

In the field of tissue engineering and biomaterials, controlling the surface properties and mechanical properties of scaffold materials is crucial and has attracted much attention. Here, two types of bilayer polymer brushes composed of a hydrophilic underlying layer and a cationic surface layer [made of poly(2-aminoethyl methacrylate)] with a thickness gradient were prepared by surface-initiated atom-transfer radical polymerization. To investigate the influence of the stiffness as a mechanical property of the polymer brush on cell behavior, the underlayer was prepared from either 2-methacryloyloxyethyl phosphorylcholine or oligo(ethylene glycol) methyl ether methacrylate, with the bilayers designated as gradient poly(2-methacryloyloxyethyl phosphorylcholine)-block-poly(2-aminoethyl methacrylate) [grad-pMbA] and gradient poly(oligo[ethylene glycol] methyl ether methacrylate)-block-poly(2-aminoethyl methacrylate) [grad-pEGbA], respectively. Characterization of these surfaces was performed by spectroscopic ellipsometry, X-ray reflectivity, and determination of the zeta potential, static contact angle, and force curve. These diblock copolymer brushes with a thickness gradient helped to distinguish the effects of the mechanical and surface properties of the brushes on cell behavior. The attachment and motility of L929 fibroblasts and epithelial MCF 10A cells on the fabricated brushes were then assessed. L929 cells had a round shape on the thin surface layer of grad-pMbA and spread well on thicker areas. In contrast, MCF 10A cells spread well in areas of any thickness of either grad-pMbA or grad-pEGbA. Single MCF 10A cells migrated randomly on grad-pMbA, whereas grouped cells started to climb up along the thickness gradient of grad-pMbA. In contrast, both single and grouped MCF 10A cells migrated randomly on grad-pEGbA. These thickness gradient diblock copolymer brushes are simple, reproducible, and reasonable platforms that can facilitate practical applications of biomaterials, for example, in tissue engineering and biomaterials.

Protocol for Analysis and Consolidation of TrackMate Outputs for Measuring Two-Dimensional Cell Motility using Nuclear Tracking.

Collective cellular migration plays a key role in many fundamental biological processes including development, wound healing, and cancer metastasis. To understand the regulation of cell motility, we must be able to measure it easily and consistently under different conditions. Here we describe a method for measuring and quantifying single-cell and bulk motility of HaCaT keratinocytes using a nuclear stain. This method includes a MATLAB script for analyzing TrackMate output files to calculate displacements, motility rates, and trajectory angles in single cells and in bulk for an imaging site. This motility analysis script allows for quick, straightforward, and scalable analysis of cell motility rates from TrackMate data and could be broadly used to identify and study the regulation of motility in epithelial cells. We also provide a MATLAB script for reorganizing microscopy videos collected on a microscope and converting them to TIF stacks, which can be analyzed using the ImageJ TrackMate plugin in bulk. Using this methodology to explore the roles of adherens junctions and actin cytoskeletal dynamics in regulating cell motility in HaCaT keratinocytes, we demonstrate evidence that Arp2/3 activity is required for the elevated motility seen after α-catenin depletion in HaCaT keratinocytes.