Biology subjects

Pelicci, G.

Publications and source records attributed to Pelicci, G..

5 recordsLinked to original sources

bioRxiv2025

Endocytic control of cell-autonomous and non-cell-autonomous functions of p53

NUMB is an endocytic protein with tumor suppressor activity, largely mediated by its ability to inhibit p53 degradation. This function depends on the inclusion of a short alternatively spliced exon (Ex3) in NUMB, although the mechanistic link between endocytosis and p53 regulation remains unclear. Here, we show that the Ex3-encoded sequence directs NUMB to the plasma membrane, where it forms a complex with the endocytic adaptor SNX9. This complex recruits p53 in a SNX9-dependent manner and is internalized and trafficked to multivesicular bodies, culminating in exosomal secretion, in a process requiring both SNX9 and NUMB. Exosomal p53 is taken up by recipient cells and translocated to the nucleus, where it activates p53-dependent transcriptional and phenotypic programs. These findings suggest that exosome-mediated p53 transfer may contribute to the establishment of a tumor-suppressive microenvironment.

cancer biology↗

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↗

bioRxiv2022

Metformin antiproliferative activity is exclusively mediated by the membrane functional expression of the Chloride Intracellular Channel 1 in glioblastoma stem cells

Metformin is the first-line drug for type-2 diabetes. Retrospective analyses, based on diabetic patients clinical data, demonstrate that daily assumption of metformin reduces the incidence of several kinds of solid tumors. Even though it is widely agreed that metformin must be internalized to accomplish its pharmacological activity, direct evidence about metformin membrane permeability and/or the presence of a specific membrane receptor in cancer cells is still missing. Here, we show that the transmembrane form of Chloride Intracellular Channel 1 (tmCLIC1) works as a privileged metformin receptor in glioblastoma stem-like cells. We found that metformin impairs tmCLIC1 activity by a specific binding coordinated by arginine 29. Its mutation, preventing metformin to bind and block tmCLIC1, abolishes the biguanide inhibition of glioblastoma cell proliferation in 2D and 3D models and metformin dependent effect on mitochondrial respiration. In addition, we demonstrate the direct binding between the drug and its target, and by in vivo experiments on zebrafish embryos and mice orthotopically engrafted with glioblastoma cells and treated with metformin, we prove that metformin binding to tmCLIC1 is crucial for metformin antineoplastic effect. Considering tmCLIC1s contribution to glioblastoma progression, the present work provides the fundaments for future development of strategies aimed at improving metformin-tmCLIC1 interaction to further increase metformin therapeutic potential.

cancer biology↗

bioRxiv2020

Adaptive mechanoproperties characterize glioblastoma fitness for invasion

Glioblastoma are heterogeneous tumors composed of highly invasive and highly proliferative clones. Heterogeneity in invasiveness could emerge from discrete biophysical properties linked to specific molecular expression. We identified clones of patient-derived glioma propagating cells that were either highly proliferative or highly invasive and compared their cellular architecture, migratory and biophysical properties. We discovered that invasiveness was linked to cellular fitness. The most invasive cells were stiffer, developed higher mechanical forces on the substrate and moved stochastically. The mechanochemical-induced expression of the formin FMN1 conferred invasive strength that was confirmed in patient samples. Moreover, FMN1 ectopic expression in less invasive clones increased fitness parameters. Mechanistically, FMN1 acts from the microtubule lattice, counteracting microtubule bundling and promoting a robust cell-body cohesion leading to highly invasive hurdling motility. One Sentence SummaryFMN1 increases cell mechanics and invasiveness.

cell biology↗