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Capsoni, S.

Publications and source records attributed to Capsoni, S..

4 recordsLinked to original sources

The mutational landscape of innervation axes in cancer

The mutational landscape of neural innervation axes in cancer has garnered increasing attention due to their significant influence on tumorigenesis, metastasis, and treatment resistance. This study provides an overview of the alterations of neural signaling pathways based on multi-omics data analysis. In particular, we conducted a comprehensive analysis of mutations in key genes associated with neurotrophin signaling, norepinephrine and cholinergic pathways, alongside paracrine and synaptogenic factors. Our findings reveal that 65% of patients in a pancancer cohort exhibit at least one somatic alteration in these pathways, with neurotrophin genes being the most frequently altered. Notably, alterations in these genes (e.g., NGF) correlate with poor patient survival across various cancer types, suggesting their oncogenic potential. We also identified significant co-occurrence of mutations and differential expression patterns from both bulk and single-cell RNAseq data, indicating complex interactions among these pathways that contribute to tumor innervation and neuroplasticity. This study underscores the necessity of understanding the crosstalk between neural signaling and cancer biology to improve patient stratification based on mutational profiles and identify potential therapeutic targets. Further research utilizing advanced genomic techniques is essential to elucidate the mechanistic roles of these pathways in tumor innervation.

genomics↗

A painless nerve growth factor variant uncouples nociceptive and neurotrophic TrkA signaling

Nerve growth factor (NGF) binding to the receptor tyrosine kinase, TrkA, drives neurotrophic signaling essential for neuronal development and survival. This interaction simultaneously drives peripheral pain, making this pathway an attractive but complicated therapeutic target for chronic pain. By integrating single-molecule microscopy, structural and electrophysiology analyses, with a human NGF variant, NGFpainless, which retains neurotrophic effects but abolishes pain, we delineate the molecular mechanisms that bias TrkA signaling towards neurotrophic functions without triggering nociception. We show that, unlike wild-type NGF, NGFpainless fails to sensitize TRPV1 channels to capsaicin, thus disengaging TrkA from the nociceptive pathway. We further show that this selective loss of nociceptive TrkA signaling by NGFpainless results from its reduced ability to activate PLC{gamma}1 and trigger calcium release compared to NGF, while still preserving the ERK and AKT signaling essential for neurotrophic functions. This biased signaling arises from reduced electrostatic complementarity at the TrkA:NGFpainless complex interface, which shortens the lifetime of this functional complex on native membranes. Mutations in TrkA that restore the electrostatic complementarity at the TrkA:NGFpainless interface eliminate biased signaling. This mechanistic understanding of TrkA binding by NGFpainless, and how it differs from NGF, will spur the development of two therapeutic classes of molecules - one that selectively suppresses nociceptive signaling while preserving neurotrophic functions in chronic pain, and another that enhances neurotrophic activity without evoking peripheral pain in neurodegenerative conditions.

neuroscience↗

Altered cortical network in Parkinson's Disease: the central role of PV interneuron and synaptic remodelling

Parkinson's disease (PD) is traditionally defined by the progressive degeneration of nigrostriatal dopaminergic neurons; however, accumulating evidence highlights extensive cortical dysfunctions as key contributors to motor and non-motor symptoms. Despite this growing recognition, the precise mechanisms underlying cortical network disruptions and their contribution to PD pathophysiology remain poorly understood, particularly in relation to parvalbumin-positive interneurons (PV-INs) and maladaptive plasticity. Here, we investigate the dysregulation of cortical network homeostasis in PD using a 6-hydroxydopamine (6-OHDA) mouse model, focusing on the progressive disruption of parvalbumin-positive interneuron (PV-IN) connectivity, excitatory/inhibitory balance, and neuroinflammatory responses. Using a multimodal approach integrating longitudinal electrophysiology, wide-field calcium imaging, and histological analyses, we revealed striking alterations in cortical activity and connectivity. Specifically, we observed pathological high-gamma hyperactivity during movement, accompanied by severe disruptions in PV-IN connectivity across motor and somatosensory cortices. Histological analyses further revealed synaptic imbalances and microglial dysregulation, suggesting an extensive cortical response to dopaminergic loss. These findings indicate that PV-IN dysfunction drives cortical maladaptive plasticity, leading to network desynchronization and motor deficits. By reframing PD as a disorder of cortical network homeostasis, this study provides novel mechanistic insights and identifies cortical plasticity as a promising therapeutic target for disease modification.

neuroscience↗

A congenital pain insensitivity mutation in the nerve growth factor gene uncouples nociception from affective pain in heterozygous humans and mice

Pain is an unpleasant but necessary sensory experience, which facilitates adaptive behaviours, such as fear. Despite recent advances, the question of how the pain experience influences learning of the fear response is still debated1,2. Genetic disorders rendering patients congenitally unable to feel pain have been described, and are usually explained by defects in peripheral nociceptors3-5. It is not known how growing up without pain affects central emotional and motivational responses to aversive stimuli. The rare autosomal recessive Hereditary Sensory and Autonomic Neuropathy type V (HSAN V) is caused by a mutation in the nerve growth factor (NGF) gene (R100W). HSAN V homozygous patients display a congenital indifference to painful events, with deficits in peripheral nociceptors but without overt cognitive impairment6. In contrast, heterozygous carriers do not present with pain-related deficits and have been identified only through pedigree and genetic screening7,8. We exploited this clinically silent population to dissociate nociceptive from affective features of pain. To address this we investigated both heterozygous knock-in mice bearing the R100W mutation (NGFR100W/m mice) and a cohort of HSAN V heterozygous human carriers. Surprisingly, we found that NGFR100W/m mice, despite normal responses to a noxious conditioning stimulus, show a deficit in learned fear while their social and innate fear responses are normal. The lack of pain-related fear response was linked to a reduced activation of anterior cingulate and motor cortices and of striatum, but not in primary somatosensory cortex. Likewise, human heterozygous R100W carriers, despite perceiving noxious stimuli and reporting subjective pain thresholds, show increased reaction latencies in response to painful stimulation, alongside a decreased subjective urgency to react. Functional magnetic resonance imaging (fMRI) revealed, comparably to the mouse data, an altered processing of painful stimuli in rostral anterior cingulate, medial premotor cortical regions and striatum. These findings from both human and mouse HSAN V carriers uncover behavioural and motivational consequences of a mild genetic pain insensitivity on the establishment of pain-dependent affective responses and memories.

neuroscience↗