👤 Viola Conte

The serotonin receptor 7 (5-HT7R) has been indicated as a key modulator of neuronal structure and function, playing critical roles in synaptic plasticity, dendritic spine formation, and cytoskeletal remodeling. 5-HT7R activation promotes neurite outgrowth, enhances long-term potentiation (LTP), stimulates local protein synthesis at synapses, and regulates mitochondrial functions, and the mTOR pathway. These properties make the 5-HT7R a compelling candidate for therapeutic intervention in neurodevelopmental disorders characterized by synaptic dysfunctions. Angelman syndrome (AS) is a severe neurodevelopmental disorder caused by the loss of function of the maternal UBE3A gene, resulting in impairments of synaptic plasticity, dendritic spine density, protein synthesis, mitochondrial activity and mTOR signaling. Intriguingly, many of the processes altered in AS are the ones that are positively regulated by 5-HT7R activation. For instance, AS animal models exhibit reduced LTP and altered dendritic morphology and 5-HT7R stimulation enhances synaptic strength and spine formation in the brain of wild type rodents. Moreover, BDNF/TrkB function signaling is impaired and mitochondrial integrity is disrupted in AS and 5-HT7R agonists enhance the altered BDNF/TrkB signalling and restore mitochondrial dysfunctions in Rett syndrome (RTT) mice model. Interestingly, recent evidence demonstrates that pharmacological activation of 5-HT7Rs increases synaptic protein synthesis, restores LTP, enhances dendritic spine density, and improves cognitive function in an AS mouse model. These encouraging results open the way to future studies using neurons and brain organoids generated from iPSCs obtained from AS patients, which represent novel tools in preclinical research. Overall, 5-HT7R stimulation, by counteracting the molecular alterations associated with the loss of UBE3A, may represent a novel approach to restore neural function in the mature brain, leading to translational applications in AS patients, and possibly also in other synaptopathies. Clinical trial number: not applicable. Show less

Approximately 40% of patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), advanced breast cancer (ABC) have PIK3CA alterations, which contributes to endocrine therapy resistance. Alpelisib, an α-selective phosphatidylinositol 3-kinase inhibitor and degrader, given in combination with fulvestrant, is approved for the treatment of PIK3CA-mutated, HR+, HER2- ABC, based on the SOLAR-1 trial. Aside from PIK3CA, other gene alterations are associated with poor prognosis and limited response to treatment in this patient population. In this retrospective analysis, we performed tissue-based next-generation sequencing of 398 patients (237 PIK3CA-altered, 161 PIK3CA-wild type) from SOLAR-1. Progression-free survival (PFS) correlative analysis was performed in the PIK3CA-altered cohort. PIK3CA-altered and PIK3CA-wild type tumors had distinct genomic profiles. In the PIK3CA-altered cohort, patients who received alpelisib plus fulvestrant had a median PFS (mPFS) of 11.01 months versus 5.55 months for those receiving placebo plus fulvestrant (P=0.0004). Patients in the lowest tumor mutational burden quartile as well as those with FGFR1 or FGFR2 alterations derived greater PFS benefit from alpelisib plus fulvestrant versus placebo plus fulvestrant (18.5 versus 3.22 months; HR 0.38; 95% CI 0.21-0.68. FGFR1 12.71 versus 3.75 months; HR 0.38; 95% CI 0.17-0.81; P=0.32. FGFR2: 9.63 versus 2.78 months; HR 0.31; 95% CI 0.1-0.94; P=0.29); patients with MYC or RAD21 alterations derived limited PFS benefit. Cox and multi-task machine learning models identified lower Eastern Cooperative Oncology Group performance status, prior cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) treatment, and PTEN or TP53 alterations among the most deleterious factors for PFS in the PIK3CA-altered cohort. Alpelisib plus fulvestrant provides clinical benefit for patients with PIK3CA-altered, HR+, HER2- ABC across a range of concomitant alterations, including those previously implicated in endocrine therapy or CDK4/6i resistance. Machine learning models identified factors including gene mutations that influenced PFS. Show less

Klotho is a longevity-associated protein found in membrane-bound and secreted forms, with the latter detectable in blood and cerebrospinal fluid (CSF). Circulating Klotho mainly originates from the kidney, while the choroid plexus (CP) secretes it into the CSF. CP dysfunction is associated with reduced Klotho expression and neurodegeneration and may result in CP enlargement on magnetic resonance imaging (MRI). In this preliminary study, we investigated Klotho levels in neurodegenerative patients and their association with CP enlargement. We retrospectively analyzed 40 patients from the IRCCS Ca' Granda Ospedale Policlinico, Milan, including 32 neurodegenerative patients (Deg) and 8 cognitively normal controls (NonDeg). CSF and serum Klotho levels were measured using an ELISA kit. KL-VS and apolipoprotein E (APOE) genotyping were performed. CP volumes were segmented using ITK-SNAP and normalized to total intracranial volume (TIV), resulting in a measure known as the CP volume fraction (CPVF). A multivariate linear regression analysis was conducted, adjusting for diagnostic group, age, sex, APOEε4, CPVF, and gray matter volume fraction (GMVF). CSF Klotho levels were significantly lower in Deg patients (mean = 729 pg./mL, SD = 364) compared to NonDeg individuals (mean = 1,077 pg./mL, SD = 220) ( In this preliminary study, we observed a strong association between CSF Klotho levels and CP enlargement. Reduced CSF Klotho levels, due to CP dysfunction, may contribute to neurodegeneration. If confirmed in larger cohorts, this association suggests that CSF Klotho may serve as a biomarker for CP enlargement, possibly reflecting its underlying dysfunction. Show less

To investigate the role of genetic testing in patients with idiopathic atrioventricular conduction disease requiring pacemaker (PM) implantation before the age of 50 years. All consecutive PM implantations in Southern Switzerland between 2010 and 2019 were evaluated. Inclusion criteria were: (i) age at the time of PM implantation: < 50 years; (ii) atrioventricular block (AVB) of unknown aetiology. Study population was investigated by ajmaline challenge and echocardiographic assessment over time. Genetic testing was performed using next-generation sequencing panel, containing 174 genes associated to inherited cardiac diseases, and Sanger sequencing confirmation of suspected variants with clinical implication. Of 2510 patients who underwent PM implantation, 15 (0.6%) were young adults (median age: 44 years, male predominance) presenting with advanced AVB of unknown origin. The average incidence of idiopathic AVB computed over the 2010-2019 time window was 0.7 per 100 000 persons per year (95% CI 0.4-1.2). Most of patients (67%) presented with specific genetic findings (pathogenic variant) or variants of uncertain significance (VUS). A pathogenic variant of PKP2 gene was found in one patient (6.7%) with no overt structural cardiac abnormalities. A VUS of TRPM4, MYBPC3, SCN5A, KCNE1, LMNA, GJA5 genes was found in other nine cases (60%). Of these, three unrelated patients (20%) presented the same heterozygous missense variant c.2531G > A p.(Gly844Asp) in TRPM4 gene. Diagnostic re-assessment over time led to a diagnosis of Brugada syndrome and long-QT syndrome in two patients (13%). No cardiac events occurred during a median follow-up of 72 months. Idiopathic AVB in adults younger than 50 years is a very rare condition with an incidence of 0.7 per 100 000 persons/year. Systematic investigations, including genetic testing and ajmaline challenge, can lead to the achievement of a specific diagnosis in up to 20% of patients. Heterozygous missense variant c.2531G > A p.(Gly844Asp) in TRPM4 gene was found in an additional 20% of unrelated patients, suggesting possible association of the variant with the disease. Show less

The spread of carbapenem-resistant Enterobacteriaceae (CRE) represents one of the most worrisome problems for clinical medicine worldwide. In Italy, the Antibiotic-Resistance-Istituto Superiore di Sanità surveillance network, in collaboration with the Committee for Antimicrobial Agents of the Italian Society of Clinical Microbiologists, promoted a study to investigate the carbapenem-resistance mechanisms, clonal relatedness and capsular typing of a recent collection of carbapenem-resistant Klebsiella pneumoniae (CR-KP). A total of 17 laboratories distributed across Italy collected all consecutive non-replicate CR-KP isolated from invasive infections during two different study periods (2011-12 and 2013). Carbapenemase genes were searched for by filter hybridization and confirmed by PCR and sequencing. KPC-producing K. pneumoniae (KPC-KP) were typed by PFGE and MLST. Capsular types were identified by wzi gene typing. Of the collected K. pneumoniae isolates (n = 461), the overall proportion of CR-KP was 36.2% (n = 167). The majority (97%) of the CR-KP were positive for the bla Although a trend to a polyclonal evolution of the Italian KPC-KP was noted, this study showed that the KPC-KP population remained largely oligoclonal with the wide diffusion of an ST512 lineage carrying cps-2 capsular type and producing the KPC-3 enzyme. Show less