[PMC free article] [PubMed] [Google Scholar]Ray A, Lee O, Win Z, Edwards RM, Alford PW, Kim D-H, and Proven-zano PP (2017)

[PMC free article] [PubMed] [Google Scholar]Ray A, Lee O, Win Z, Edwards RM, Alford PW, Kim D-H, and Proven-zano PP (2017). protrusions to diminish the CG response and define Arp2/3- and Formins-dependent actin architectures that regulate microtu-bule-dependent protrusions, which promote the CG response. Thus, our work represents a comprehen-sive examination of the physical mechanisms influ-encing CG sensing. In Brief Aligned extracellular matrix architectures in tumors direct migration of invasive malignancy cells. Tabdanov et al. show that the mechanical properties of aligned extracellular matrix environments influence invasive cell behavior and define a mechanical role for microtubules and actomyosin-microtubule interactions during sensing of contact guidance cues that arise from aligned extracellular matrix. Graphical Abstract INTRODUCTION Sensing contact guidance cues and subsequent directed cell migration are essential phenomena that govern numerous processes such as morphogenesis (Daley and Yamada, 2013), immune cell migration (Friedl and Br?cker, 2000), and metastatic dissemination (Conklin et al., 2011; Patsialou et al., 2013; Provenzano et al., 2006). However, despite progress toward understanding the principles of cell-extracellular matrix (ECM) architecture sensing, contradictory paradigms have emerged. For example, actomyosin contractility has been reported to be both dispensable Artn or necessary for fibroblast contact guidance (CG) along one-dimensional (1D) cues (Doyle et al., 2009, 2012; Guetta-Terrier et al., 2015), while carcinoma cell contractility is essential for ECM alignment (Carey et al., 2013; Proven-zano et al., 2008), but dispensable for migration through prealigned ECM (Provenzano et al., 2008). Thus, both cell and ECM mechanics may influence the 1D, 2D, or 3D CG response (Carey et al., 2015; Chang et al., 2013; Doyle et al., 2009; Provenzano et al., 2006, 2008; Ray et al., 2017). However, surprisingly opposite styles in CG behavior have been reported depending on whether traction is usually modulated intrinsically (by targeting myosin) or extrinsically (by changing substrate stiffness) (Nuhn et al., 2018). As such, questions remain regarding the influence of effective traction during CG sensing. Therefore, novel platforms are needed that allow for concurrent control of both mechanical rigidity and ECM architecture across multiple scales to parse out complex CG sensing behavior. Regulation of CG-directed cell migration BRD4770 has been attributed to lamellipodia along protrusive edges, as well as filopodia, pseudopodia, and invadopodia (Albuschies and Vogel, 2013; Doyle et al., 2009, 2012; Jacquemet et al., 2015; Teixeira et al., 2003). In sum, resultant cell orientation can be attributed to competitive dynamics between multidirectional lamellipodia distributing featuring Arp2/3-branched F-actin with circular con-tractile transverse arcs and more directed protrusions featuring Formins-driven radially directed ventral and dorsal stress fibers (SFs) (Hotulainen and Lappalainen, 2006; Oakes et al., 2012), suggesting that concurrent counterbalancing cytoskeleton dynamics could regulate the robustness of the CG response, consistent with transverse lamellipodia distributing across densely arrayed lines that can compete with the directed CG response (Ramirez-San Juan et al., 2017; Romsey et al., 2014). A similar interference has also been suggested to influence CG along nanogrooves (Lee et al., 2016; Ray et al., 2017; Teixeira et al., 2003). However, the mechanisms governing cell conformity to CG topography are poorly comprehended. Intriguingly, reports relate microtubules (MTs) to topography sensing (Lee et al., 2016; Oakley and Brunette, 1995), cell conformity to fibrillar 3D network (Bouchet and Akhmanova, 2017; Rhee et al., 2007), and compression resistance in cell leading edge of contracting cells (Brangwynne et al., 2006), suggesting that increased understanding of the structural and mechanical functions of MTs during CG may BRD4770 increase our understanding of directed motility. Thus, here using designed CG platforms, we address fundamental questions regarding competitive protrusion behavior and elucidate the physical and molecular mechanisms governing lamellipodia- and MT-regulated CG sensing. RESULTS Engineering Multiscale Mechano-structural Contact Guidance Cues The current paradigm of CG from 2D smooth or textured surfaces links cell alignment (and directed migration) to alignment of focal adhesions (FAs), SFs, and directed cell protrusions (Doyle et al., 2009; Ramirez-San Juan et al., 2017; Ray et al., 2017; Romsey et al., 2014). However, the impact of mechanosensitivity during CG-directed cell alignment is far less explored due to challenges engineering environments with nanoscale and/or microscale CG cues of variable stiffness. As such, we designed platforms with type I collagen CG cues of defined mechanical rigidities BRD4770 and oriented architectures (i.e., dense quasi-2D nanolines, 1D microlines, and 2.5D topographic CG cues: Determine 1; see STAR Methods for full platforms descriptions) to study CG sensing, and in particular, competitive dynamics between CG-directed protrusions versus non-oriented multidirectional distributing. Furthermore, the topographic features of nanotextured CG cues are sterically interactive at the nanoscale but.