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Cantini, M.

Publications and source records attributed to Cantini, M..

3 recordsLinked to original sources

Matrix viscoelasticity controls epithelial cell mechanobiology through dimensionality

In recent years, matrix viscoelasticity has emerged as a potent regulator of fundamental cellular processes and has been implicated in promoting cancer progression. Alongside viscoelasticity, additional ECM cues have been shown to influence migration decision-making of cancer cells, and spatial confinement is now considered as a potential regulator of metastasis. However, our understanding of these complex processes predominantly relies on purely elastic hydrogels, and the exact relationship between matrix viscoelasticity and spatial confinement in driving epithelial cell mechanotransduction and migration during cancer progression remains unclear. Here, we systematically investigated the interplay between matrix stiffness, viscoelasticity and spatial confinement by engineering soft ([~]0.3 kPa) and stiff ([~]3 kPa) polyacrylamide hydrogels with varying degrees of viscous dissipation, mirroring the mechanical properties of healthy and tumoral conditions in breast tissue. We observed that viscoelasticity modulates cell spreading, focal adhesions and YAP nuclear import in opposite directions on soft and stiff substrates. Strikingly, viscoelasticity enhances migration speed and persistence on soft substrates, while impeding them on stiff substrates via actin retrograde flow regulation. Combining soft micropatterning with viscoelastic hydrogels, we also show that spatial confinement restricts cell migration on soft matrices regardless of matrix viscoelasticity and promotes migration on stiff matrices in a viscoelasticity-dependent fashion. Our findings establish substrate viscoelasticity as a key regulator of epithelial cell functions and unravel the role of the matrix dimensionality in this process. SignificanceWhile matrix elasticity has received significant attention, recent findings underscore the importance of its natural dissipative properties and spatial confinement in regulating cellular processes and tumour invasiveness. However, the intricate interplay between viscoelasticity and spatial confinement in orchestrating epithelial cell behaviour during cancer progression remains elusive. Using micropatterned viscoelastic hydrogels to replicate the mechanical properties encountered during breast tumour progression, we unveil that viscoelasticity modulates cell behaviour and mechanotransduction signals differently on soft and stiff substrates. Increased viscoelasticity enhances migration speed and persistence on soft substrates while impeding them on stiff substrates via actin retrograde flow regulation. Furthermore, spatial confinement restricts cell migration on soft matrices regardless of viscoelasticity, while promoting migration on stiff matrices in a viscoelasticity-dependent manner.

biophysics↗

Mind the viscous modulus: The mechanotransductive response to the viscous nature of isoelastic matrices regulates stem cell chondrogenesis

The design of hydrogels as mimetics of tissues matrices typically disregards the viscous nature of native tissues and focuses only on their elastic properties. In the case of stem cell chondrogenesis, this has led to contradictory results, likely due to unreported changes of the matrices viscous modulus. Here, by employing isoelastic matrices with a Youngs modulus of ~12 kPa, we demonstrate that variations in viscous properties alone (i.e., loss tangent between 0.1-0.25) are sufficient to drive efficient growth factor-free chondrogenesis of human mesenchymal stem cells, both in 2D and 3D cultures. The increase of the viscous component of RGD-functionalised polyacrylamide or polyethylene glycol maleimide hydrogels promotes a phenotype with reduced adhesion, alters mechanosensitive signalling, and boosts cell-cell contacts. In turn, this upregulates the chondrogenic transcription factor SOX9 and supports neocartilage formation, demonstrating that the mechanotransductive response to the viscous nature of the matrix can be harnessed to direct cell fate.

bioengineering↗

Material-Driven Fibronectin Assembly Rescues Matrix Defects due to Mutations in Collagen IV in Fibroblasts

Basement membranes (BMs) provide structural support to tissues and influence cell signaling. Mutations in COL4A1/COL4A2, a major BM component, cause eye, kidney and cerebrovascular disease, including stroke. Common variants in these genes are risk factors for intracerebral hemorrhage in the general population. However, the contribution of the matrix to the disease mechanism(s) and its effects on the biology of cells harboring a collagen IV mutation remain poorly understood. To shed light on this, we engineered controlled microenvironments using polymer biointerfaces coated with ECM proteins laminin or fibronectin (FN), to investigate the cellular phenotype of primary fibroblasts harboring a COL4A2+/G702D mutation. FN nanonetworks assembled on poly(ethyl acrylate) (PEA) induced increased deposition and assembly of collagen IV in COL4A2+/G702D cells, which was associated with reduced ER size and enhanced levels of protein chaperones such as BIP, suggesting increased protein folding capacity of cells. FN nanonetworks on PEA also partially rescued the reduced stiffness of the deposited matrix and cells, and enhanced cell adhesion through {beta}1-mediated signaling and actin-myosin contractility, effectively rescuing some of the cellular phenotypes associated with COL4A1/4A2 mutations. Collectively, these results suggest that biomaterials are able to shape the matrix and cellular phenotype of the COL4A2+/G702D mutation in patient-derived cells.

bioengineering↗