Biology subjects

Dini, T.

Publications and source records attributed to Dini, T..

4 recordsLinked to original sources

bioRxiv2024

Unraveling Glioblastoma Heterogeneity: Introducing SP2G Method for Identifying Invasive Sub-Populations

Glioblastomas exhibit remarkable heterogeneity at various levels, including motility modes and mechanoproperties that contribute to tumor resistance and recurrence. In a recent study using gridded micropatterns mimicking the brain vasculature, we linked glioblastoma cell motility modes, mechanical properties, formin content, and substrate chemistry. We now introduce SP2G (SPheroid SPreading on Grids), an analytic platform designed to identify the migratory modes of patient-derived glioblastoma cells and rapidly pinpoint the most invasive sub-populations. Tumorspheres are imaged as they spread on gridded micropatterns and analyzed by our semi-automated, open-source, Fiji macro suite that characterizes migration modes accurately. With SP2G, we could reveal intra-patient motility heterogeneity with molecular correlations to specific integrins and EMT markers. Thus, our system presents a versatile and potentially pan-cancer workflow to detect diverse invasive tumor sub-populations in patient-derived specimens and offers a valuable tool for therapeutic evaluations at the individual patient level. TeaserCracking the inter and intra-patient diversity in Glioblastoma migration profiles

biophysics↗

bioRxiv2023

SP2G: an imaging and analysis pipeline revealing the inter and intra-patient migratory diversity of glioblastoma

Glioblastomas are heterogeneous, primary brain tumors hiding several sub-populations. Patient-derived xenografts are considered gold-standards to study glioblastoma invasion. However, they present many disadvantages, including time consumption, complex standardization, high cost. To counteract these issues and rapidly identify the most invasive sub-populations, we developed an in vivo mimicry platform named SP2G (SPheroid SPreading on Grids). Live imaging of tumor-derived spheroids spreading on gridded micro patterns mimicking the brain vasculature recapitulated 3D motility features observed in brain or 3D matrices. Using patient-derived samples coupled with a semi-automated macro suite, SP2G easily characterized and sorted differences in cell migration and motility modes. Moreover, SP2G exposed the hidden intra-patient heterogeneity in cell motility that correlated molecularly to specific integrins. Thus, SP2G constitute a versatile and potentially pan-cancer workflow to identify the diverse invasive tumor sub-populations in patient-derived specimens. SP2G includes an integrative tool, available as open-source Fiji macro suite, for therapeutic evaluations at single patient level. TeaserCracking the inter and intra-patient diversity in Glioblastoma migration profiles

biophysics↗

bioRxiv2021

The glycocalyx affects force loading-dependent mechanotransductive topography sensing at the nanoscale

The cell/microenvironment interface is the starting point of integrin-mediated mechanotransduction, but many details of mechanotransductive signal integration remain elusive due to the complexity of the involved (extra)cellular structures, such as the glycocalyx. We used nano-bio-interfaces reproducing the complex nanotopographical features of the extracellular matrix to analyse the glycocalyx impact on PC12 cell mechanosensing at the nanoscale (e.g., by force spectroscopy with functionalised probes). Our data demonstrates that the glycocalyx configuration affects spatio-temporal nanotopography-sensitive mechanotransductive events at the cell/microenvironment interface. Opposing effects of glycocalyx removal were observed, when comparing flat and specific nanotopographical conditions. The excessive retrograde actin flow speed and force loading are strongly reduced on certain nanotopographies upon removal of the native glycocalyx, while on the flat substrate we observe the opposite trend. Our results highlight the importance of the glycocalyx configuration in a molecular clutch force loading-dependent cellular mechanism for mechanosensing of microenvironmental nanotopographical features.

biophysics↗

bioRxiv2020

Adhesion force spectroscopy with nanostructured colloidal probes reveals nanotopography-dependent early mechanotransductive interactions at the cell membrane level

Mechanosensing, the ability of cells to perceive and interpret the microenvironmental biophysical cues (such as the nanotopography), impacts strongly on cellular behaviour through mechanotransductive processes and signalling. These events are predominantly mediated by integrins, the principal cellular adhesion receptors located at the cell/extracellular matrix (ECM) interface. Because of the typical piconewton force range and nanometre length scale of mechanotransductive interactions, achieving a detailed understanding of the spatiotemporal dynamics occurring at the cell/microenvironment interface is challenging; sophisticated interdisciplinary methodologies are required. Moreover, an accurate control over the nanotopographical features of the microenvironment is essential, in order to systematically investigate and precisely assess the influence of the different nanotopographical motifs on the mechanotransductive process. In this framework, we were able to study and quantify the impact of microenvironmental nanotopography on early cellular adhesion events by means of adhesion force spectroscopy based on innovative colloidal probes mimicking the nanotopography of natural ECMs. These probes provided the opportunity to detect nanotopography-specific modulations of the molecular force loading dynamics and integrin clustering at the level of single binding events, in the critical time window of nascent adhesion formation. Following this approach, we found that the nanotopographical features are responsible for an excessive force loading in single adhesion sites after 20 - 60 s of interaction, causing a drop in the number of adhesion sites. However, by manganese treatment we demonstrated that the availability of activated integrins is a critical regulatory factor for these nanotopography-dependent dynamics.

biophysics↗