Biology subjects

Caswell, P.

Publications and source records attributed to Caswell, P..

4 recordsLinked to original sources

bioRxiv2024

Live-cell magnetic micromanipulation of recycling endosomes reveals their direct effect on actin-based protrusions to promote invasive migration

Endocytic recycling pathways play key roles in the re-routing of cargoes through the cell to control a broad range of cellular processes, and many vesicle trafficking regulators are implicated in progression of disease such as cancer. The Rab11 family (Rab11a, Rab11b, and Rab25) control return of internalised cargoes to the plasma membrane, and Rab25 has been implicated in the aggressiveness of cancer by promoting invasive migration. However, whilst Rab25 vesicles distribute to the leading of edge of moving cells, how directly they contribute to cell protrusion is not clear. Here we adopt a magnetogenetic approach that allows direct manipulation of Rab25 positioning to show that localisation to the cell periphery drives the formation of F-actin protrusions. We demonstrate that endogenous Rab25 vesicles coordinate the positioning of key cargoes, including the actin regulator FMNL1 and integrin {beta}1, with the activation of Rho GTPases at the plasma membrane to generate and maintain F-actin rich filopodial protrusions and promote cancer cell invasive migration in 3D matrix.

cancer biology↗

bioRxiv2021

3D matrix adhesion composition facilitates nuclear force coupling to drive invasive cell migration

Cell invasion and metastasis is a multi-step process, initialised through the acquisition of a migratory phenotype and the ability to move through differing and complex 3D extracellular environments. In this study we set out to identify the parameters required for invasive cell migration in 3D environments. Cells interact with the extracellular matrix via transmembrane-spanning integrin adhesion complexes, which are well characterised in cells plated on 2D surfaces, yet much less is known about them in cells embedded in 3D matrices. We establish a technique to determine the composition of cell matrix adhesion complexes of invasive breast cancer cells in 3D matrices and on 2D surfaces and we identify an interaction complex enriched in 3D adhesive sites required for 3D invasive migration. Depletion of {beta}-PIX-Myosin18A (Myo18A) abolishes cancer cell invasion, without negatively affecting matrix degradation, Rho GTPase signalling, or protrusion formation in collagen matrices. Instead, in a mechanism only seen in cells moving through 3D matrix, {beta}-PIX and Myo18A drive the polarised recruitment of non-muscle Myosin 2A (NM2A) to the tips of protrusions. This recruitment of NM2A is required for the creation of an NM2A-NM2B isoform gradient, which ranges from the protrusion to the nucleus. We observe a requirement for active force transmission to the nucleus during invasive migration that is needed to pull the nucleus forward. We postulate that the establishment of the NM2A-NM2B actomyosin gradient facilitates the coupling of cell-matrix interactions at the protrusive cell front with nuclear movement, enabling effective invasive migration and front-rear cell polarity.

cell biology↗

bioRxiv2020

Combinatorial mathematical modelling approaches to interrogate rear retraction dynamics in 3D cell migration

Cell migration in 3D micro-environments is a complex process which depends on the coordinated activity of leading edge protrusive force and rear retraction in a push-pull mechanism. While the potentiation of protrusions has been widely studied, the precise signalling and mechanical events that lead to forward movement of the cell rear are much less well understood, particularly in physiological 3D extra-cellular matrix (ECM). We previously discovered that rear retraction in fast moving cells is a highly dynamic process involving the precise spatiotemporal interplay of mechanosensing by caveolae and signalling through RhoA. To further interrogate the dynamics of rear retraction, we have adopted three distinct mathematical modelling approaches here based on (i) Boolean logic, (ii) deterministic kinetic ordinary differential equations (ODEs) and (iii) stochastic simulations. The aims of this multi-faceted approach are twofold: firstly to derive new biological insight into cell rear dynamics via generation of testable hypotheses and predictions; and secondly to compare and contrast the distinct modelling approaches when used to describe the same, relatively under-studied system. Whilst Boolean logic was not able to fully recapitulate the complexity of rear retraction signalling completely, our ODE model could make plausible population level predictions. Stochastic simulations added a further level of complexity by accurately mimicking previous experimental findings and acting as a single cell simulator. Our approach has also highlighted the unanticipated potential of targeting CDK1 to abrogate cell movement, a prediction we confirmed experimentally. Moreover, we have made a novel prediction regarding the potential existence of a set point in local stiffness gradients that promotes polarisation and rapid rear retraction. Overall, our modelling approaches complement each other, suggesting that such a multi-faceted approach is more informative than methods based on a single modelling technique to interrogate biological systems.

cell biology↗

bioRxiv2019

ISGylation drives basal breast tumour progression by promoting EGFR recycling and Akt signalling

ISG15 is an ubiquitin-like modifier that is associated with reduced survival rates in breast cancer patients. However, the mechanism by which ISG15 achieves this remains elusive. We demonstrate that modification of Rab GDP-Dissociation Inhibitor Beta (GDI2) by ISG15 (ISGylation) alters endocytic recycling of the EGF receptor (EGFR). By regulating EGFR trafficking, ISGylation sustains Akt-signalling in vitro and in vivo. Persistent and enhanced Akt activation explains the more aggressive tumour behaviour observed in animal models and human breast cancers. We show that ISGylation can act as driver of tumour progression rather than merely being a marker of it.

cancer biology↗