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Proteolysis-targeting chimeras (PROTACs) describe compounds that bind to and induce degradation of a target by simultaneously binding to a ubiquitin ligase. More generally referred to as bifunctional degraders, PROTACs have led the way in the field of targeted protein degradation (TPD), with several compounds currently undergoing clinical testing. Alongside bifunctional degraders, single-moiety compounds, or molecular glue degraders (MGDs), are increasingly being considered as a viable approach for development of therapeutics, driven by advances in rational discovery approaches. This review focuses on drug discovery with respect to bifunctional and molecular glue degraders within the ubiquitin proteasome system, including analysis of mechanistic concepts and discovery approaches, with an overview of current clinical and pre-clinical degrader status in oncology, neurodegenerative and inflammatory disease.

We investigate the interaction between an electron beam and a THz guided electromagnetic wave in a helical slow-wave structure formed by self-assembly of a conductive ribbon. We have previously shown the controlled fabrication of this slow-wave structure and its potential to form the basis for widely deployable millimeter-through-THz traveling-wave tube amplifiers. The process allows the fabrication of helical slow-wave structures with single and double chirality. Here, we use three-dimensional simulations to perform a comparative analysis of beam–wave interaction in self-assembled gold helices with single and double chirality. First, the structures are modeled without the electron beam (cold helices) to calculate the distribution of the electric field generated by the high-frequency wave. We perform simulations of cold helices by using Computer Simulation Technology Microwave Studio. Second, we evaluate the interaction between an electron beam and the THz travelingwave by using a particle in cell simulator in Computer Simulation Technology Particle Studio. Simulation studies show that a switch in chirality in the middle of self-assembled helices generates a reflected wave that boosts beam–wave interaction. We demonstrate that this efficient energy exchange will potentially provide high gain in THz traveling-wave tube amplifiers based on self-assembled helices.

Abstract Background Autism spectrum disorder (ASD) is a highly prevalent neurodevelopmental condition affecting almost 1% of children, and represents a major unmet medical need with no effective drug treatment available. Duplication at 7q11.23 (7Dup), encompassing 26–28 genes, is one of the best characterized ASD-causing copy number variations and offers unique translational opportunities, because the hemideletion of the same interval causes Williams–Beuren syndrome (WBS), a condition defined by hypersociability and language strengths, thereby providing a unique reference to validate treatments for the ASD symptoms. In the above-indicated interval at 7q11.23, defined as WBS critical region, several genes, such as GTF2I, BAZ1B, CLIP2 and EIF4H, emerged as critical for their role in the pathogenesis of WBS and 7Dup both from mouse models and human studies. Methods We performed a high-throughput screening of 1478 compounds, including central nervous system agents, epigenetic modulators and experimental substances, on patient-derived cortical glutamatergic neurons differentiated from our cohort of induced pluripotent stem cell lines (iPSCs), monitoring the transcriptional modulation of WBS interval genes, with a special focus on GTF2I, in light of its overriding pathogenic role. The hits identified were validated by measuring gene expression by qRT-PCR and the results were confirmed by western blotting. Results We identified and selected three histone deacetylase inhibitors (HDACi) that decreased the abnormal expression level of GTF2I in 7Dup cortical glutamatergic neurons differentiated from four genetically different iPSC lines. We confirmed this effect also at the protein level. Limitations In this study, we did not address the molecular mechanisms whereby HDAC inhibitors act on GTF2I. The lead compounds identified will now need to be advanced to further testing in additional models, including patient-derived brain organoids and mouse models recapitulating the gene imbalances of the 7q11.23 microduplication, in order to validate their efficacy in rescuing phenotypes across multiple functional layers within a translational pipeline towards clinical use. Conclusions These results represent a unique opportunity for the development of a specific class of compounds for treating 7Dup and other forms of intellectual disability and autism.

OBIETTIVI I Centri di Radioterapia UPMC San Pietro FBF di Roma (CC#1) e UPMC Villa Maria di Mirabella Eclano (CC#2) hanno condotto uno studio con l’obiettivo di analizzare le variazioni avvenute durante la pandemia sui workload e i workflow di reparto. È stato, inoltre, ricercato l’eventuale nesso tra queste e l’introduzione di nuove procedure per la prevenzione e il contenimento del contagio da Covid-19. MATERIALI E METODI I dati utilizzati sono stati ricavati da reports presenti nel sistema ARIA (V.15.1 Varian Medical System, CA, Palo Alto, USA). Per esaminare i workload è stato utilizzato il Downtime, un indicatore che quantifica direttamente l'inattività del reparto, ricavato dal rapporto tra il tempo di standby giornaliero dei LINAC (TrueBeam STx®, Varian Medical System, CA, Palo Alto, USA) e la media di trattamenti giornalieri effettuati. Per esaminare workflow ed eventuali ritardi tra le attività, sono stati valutati gli intervalli di tempo tra una terapia e la successiva (Intervalli di terapia). RISULTATI Il Downtime nel CC#1 ha subìto un leggero aumento del valore medio dal 3.1% del 2019 al 3.8% del 2020, tuttavia l’analisi mensile mostra consistenti picchi di riduzione (marzo-aprile-maggio) e di incremento (novembre-dicembre). Per il CC#2 il trend del Downtime nel 2020 è abbastanza regolare (valore medio del 3,3%), con un incremento durante la prima ondata della pandemia. Gli Intervalli di terapia di “5-10 min” nel CC#1, analizzati confrontando il trimestre marzo-aprile-maggio 2020 col 2019, risultano maggiori per i primi mesi e ridotti a maggio; quelli di “10-15” min risultano stabili; quelli “>20 min” sono leggermente aumentati a marzo 2020. Per il CC#2 il trend nel 2020 decresce nei mesi di maggiore emergenza sanitaria e incrementa nei mesi estivi. CONCLUSIONI Il fatto che i trend degli indicatori utilizzati abbiano dei picchi esclusivamente in corrispondenza dei periodi di maggiore emergenza sanitaria, è indice di un certo impatto – sia in termini di workload che di workflow – della pandemia, ma anche della capacità del personale di adattarsi in breve tempo alle nuove procedure da eseguire, senza inficiare sul rendimento generale dei Centri.

INTRODUZIONE I successi della moderna radioterapia sono spesso guidati da elevati standard di qualità. Questo studio punta a valutare percorsi di cura automatizzati e personalizzabili per definire nuovi indicatori di qualità quantitativi in radioterapia oncologica, al fine di ottimizzare l’efficienza e la sicurezza dei servizi erogati. MATERIALI E METODI Per questo studio, sono stati coinvolti due centri oncologici internazionali appartenenti allo stesso network (UPMC San Pietro di Roma (CC#1) ed UPMC Villa Maria di Mirabella Eclano (CC#2)), entrambi dotati di un acceleratore lineare ed uno scanner TC. L’analisi dei dati ha preso in considerazione il periodo compreso tra gennaio 2019 e dicembre 2019. Seguendo il workflow delle attività di entrambi i centri, nello sviluppo della cartella clinica elettronica, sono stati creati dei modelli automatizzati adattabili alle differenti tipologie di trattamento, e quindi personalizzabili per ciascun paziente: utilizzando il software ARIA v15 (Varian Medical System, CA, Palo Alto, USA), abbiamo convertito tutti gli step del percorso di cura del paziente in moduli che hanno la possibilità di essere collegati per andare a formare il processo di cura del paziente stesso. I “Carepaths” infatti, rappresentano dei moduli in un processo automatizzato all’interno dei quali sono presenti attività (“task”) e appuntamenti (“appointment”), aventi dei tempi di esecuzione ben definiti entro i quali devono essere completati elettronicamente. Per avere un riferimento in merito alle prestazioni in termini quantitativi riguardo i centri, abbiamo focalizzato l’attenzione su tre fattori: percentuale di attività completate in relazione al tempo di esecuzione, giorni trascorsi e compliance dello staff con l’utilizzo di questo sistema automatizzato. RISULTATI La misurazione delle attività completate consente di definire la conformità del processo automatizzato ai percorsi assistenziali, mentre le tempistiche del completamento delle attività consentono di determinare le aree di miglioramento. In questo studio, i "Timeout" vengono sempre eseguiti con puntualità, ma i risultati su "Peer Review" e "Treatment Approval" non sono soddisfacenti. Un tempo di ritardo definito ci consente di tenere traccia delle attività in modo preciso, e l’analisi di questi valori in entrambi i centri oncologici presi in analisi, ci consente di capire se il tempo di consegna per le attività è appropriato o se c'è un margine di miglioramento. Tutti i dati osservati mostrano che la percentuale di attività completate in entrambi i centri oncologici e i tempi trascorsi per il completamento delle stesse sono differenti. CONCLUSIONI I percorsi assistenziali automatizzati, con i relativi moduli, possono essere uno strumento valido ed efficiente per misurare le attività in un reparto di radioterapia oncologica, soprattutto se utilizzati come strumento di miglioramento continuo della qualità delle prestazioni.

GOALS The Advanced Radiotherapy Centers of UPMC San Pietro FBF of Rome (CC#1) and UPMC Villa Maria of Mirabella Eclano (CC#2) conducted a study to review variations in department workloads and workflows experienced during the pandemic. The potential relation between these variations and the new procedures introduced to prevent and contain the COVID-19 infection was also studied. MATERIALS AND METHODS The data used were obtained from reports present in the ARIA® system (v. 15.1 Varian Medical Systems, Palo Alto, CA, U.S.A.). To examine the workloads was used the Downtime, an indicator that directly quantifies the inactivity of the department, derived from the ratio between the daily stand-by time of the LINACs (TrueBeam STx®, Varian Medical Systems, Palo Alto, CA, U.S.A.) and the mean number of treatments performed every day. In order to examine the workflows and possible delays, we measured the time between the treatments ("Therapy intervals"). RESULTS The Downtime average at CC#1 slightly increased from 3.1% in 2019 to 3.8% in 2020. However, the monthly analysis shows significant reduction (March-April-May) and increase (November-December) peaks. At CC#2, the 2020 Downtime trend was fairly consistent (average value: 3.3%), with an increase during the first wave of the pandemic. The "5-10 min" Therapy intervals at CC#1, reviewed comparing the March-April-May 2020 quarter with 2019, were higher in the first months and lower in May; the "10-15 min" intervals were stable; the ">20 min" intervals slightly increased in March 2020. At CC#2, the trend in 2020 decreased during the months of higher health care emergency and increased during the summer months. CONCLUSIONS The fact that the trends of the indicators show peaks only during the periods of major health care emergency indicates an impact of the pandemic, both on the workload and on the workflow. However, they also highlight the staff's ability to rapidly adapt to the new procedures, without affecting the overall performance of the both centers.

INTRODUCTION High quality standards are often the key for success in modern radiotherapy. The goal of this study is to assess automated and targeted care paths to define new quantitative quality indicators in radiation oncology and optimize the efficiency and safety of the services provided. MATERIALS AND METHODS For this study, two international cancer centers part of the same network (UPMC San Pietro in Rome (CC#1) and UPMC Villa Maria in Mirabella Eclano (CC#2)) have been involved, both equipped with a linear accelerator and a CT scan. The data reviewed refers to a period between January 2019 and December 2019. Following the workflow of both centers during electronic medical record data input, we created automated models adaptable to the different types of treatment and customizable for each patient. Using the ARIA v15 (Varian Medical System, CA, Palo Alto, USA) software, we converted the various steps of the care path in modules that can be connected to create the patient's care process. Care paths are therefore modules of an automated process consisting of tasks and appointments, with well-defined execution times within which they must be completed electronically. To obtain quantitative information on both centers we focused on three factors: tasks completed in relation to their execution times, number of days, and staff compliance with the automated system. RESULTS Measuring the completed tasks allows to define the compliance of the automated process with the care paths, whereas the time required to complete the tasks helps identify areas for improvement. Within this study timeouts are always performed on time, but peer review and treatment approval outcomes are unsatisfactory. A defined delay time allows to keep track of tasks in a precise manner and reviewing these values in both centers helps us understand if the task delivery time is appropriate or if there is room for improvement. All analyzed data show that the percentage of tasks completed in both centers and the completion times are different. CONCLUSIONS Automated care paths and their modules can be an effective and efficient tool to measure the tasks performed by a radiation oncology unit, especially if they are used as a tool of continuous quality improvement.

INTRODUZIONE La radioterapia adattiva è una pratica clinica consolidata, soprattutto in alcuni tipi di trattamenti soggetti a rapidi cambiamenti a causa della presenza di organi a rischio (OAR) che influenzano il movimento del target. Il processo di adattabilità del trattamento al singolo caso combina strumenti come l’acquisizione di immagini pretrattamento, la valutazione clinica del reale bisogno di adattamento, la pianificazione del nuovo trattamento e la garanzia della qualità finale di questo processo. Le moderne apparecchiature di radioterapia permettono di attuare diverse strategie in modalità online o offline. Lo scopo di questo lavoro è definire una procedura di ART offline capace di garantire un corretto replanning nei trattamenti prostatici secondo parametri di valutazione oggettivi. MATERIALI E METODI Il protocollo di simulazione e trattamento dei pazienti prostatici prevede lo svuotamento dell’ampolla rettale (quando ritenuto clinicamente necessario) e il riempimento della vescica previa assunzione di un predeterminato volume d’acqua da parte del paziente e un’attesa utile al defluire dell’urina nella stessa. Affinchè le condizioni della simulazione vengano rispettate anche durante il trattamento, si effettuano controlli giornalieri tramite immagini CBCT. Il protocollo IGRT prevede la fusione rigida delle immagini acquisite nel bunker con quelle derivate dalla TC di simulazione. Per lo studio sono stati selezionati 23 pazienti affetti da adenocarcinoma della prostata (medio e basso rischio) sottoposti a 40 frazioni con una dose giornaliera di 2Gy/die (80 Gy). I pazienti sono stati trattati in posizione supina, le braccia sopra il torace e le gambe su un sistema di immobilizzazione (Prostep Klarity). Il workflow ART offline ha richiesto l’uso delle verifiche pretrattamento, la registrazione con le immagini della simulazione e il calcolo delle variazioni di riempimento di retto e vescica. L’analisi è stata effettuata tramite software Velocity v4.0 (Varian Medical System). Alla fine del procedimento automatico generato dal software Velocity, si sono rese disponibili delle immagini adattate tra TC e CBCT chiamate aCT (adaptive CT). La contornazione degli organi di interesse sulle aCT è avvenuta in maniera automatica. Per permettere un confronto quantitativo efficace sono stati presi in considerazione il coefficiente di DICE e indici statistici di dispersione e distribuzione. RISULTATI La dispersione dei valori percentuali relativi al volume del retto risulta maggiore nei casi afferenti al gruppo A. La distribuzione delle percentuali di cambiamento del retto nel gruppo A ha avuto come valore IQR = 5,55% (Q1=-4,06%; Q2= -1,13%; Q3= 1,49%) mentre nel gruppo B IQR= 4,24% (Q1= -2,50%; Q2= 2,09%; Q3= 1,75%). La dispersione dei valori percentuali relativi al volume della vescica risulta maggiore nei casi afferenti al gruppo A. La distribuzione delle percentuali di cambiamento della vescica nel gruppo A ha avuto come valore IQR = 9,65% (Q1=-7,34%; Q2= -2,32%; Q3= 2,31%) mentre nel gruppo B IQR= 12,13% (Q1= -7,18%; Q2= -1,56%; Q3= 4,96%). Il coefficiente di DICE nel gruppo A ha evidenziato una sovrapponibilità giornaliera della vescica in media pari a 0,91 ± 0,07. Nel gruppo B, la stessa sovrapponibilità ha raggiunto il valore medio di 0,92 ± 0,06. Il volume del retto, nel gruppo A ha avuto coefficiente di Dice medio pari a 0,87 ± 0,10, mentre nel gruppo B la stessa sovrapponibilità ha raggiunto un valore medio di 0,89 ± 0,09. CONCLUSIONI Dai risultati ottenuti si evince che il valore del coefficiente DICE è un indice utile per stabilire se la localizzazione dei volumi è sovrapponibile a quella della TC di simulazione. Andrebbe perciò verificato, in fase di attuazione di un protocollo di ART Offline, per le prime cinque frazioni di terapia, ritenute nella nostra pratica clinica un tempo utile affinché si possa stimare velocemente l’effettiva necessità di ripianificazione. Poiché questo indice non prende in considerazione i volumi ma solo la loro sovrapponibilità geometrica, in caso di adozione di un workflow di radioterapia adattiva offline, si consiglia di effettuare anche un controllo delle medie dei volumi degli OAR, soprattutto per quel che concerne la vescica, più soggetta a cambiamenti di questo tipo che di variazioni della localizzazione spaziale.

INTRODUCTION Adaptive radiation therapy (ART) is an established clinical practice, especially for treatments requiring rapid changes due to organs-at-risk (OAR) that might influence the target position. Adapting the procedure to a case-to-case basis involves combining different tools, such as scanning pretreatment images, clinically assessing the need for adaptation, replanning a new treatment, and guaranteeing the final quality of the entire process. Modern radiation therapy equipment enables multiple optimization strategies, both online and offline. The primary aim of this study is to define an offline ART procedure to correct the replanning of prostate treatments according to objective evaluation criteria. MATERIALS AND METHOS The simulation and treatment protocols for prostate patients involve emptying the rectum when needed and ensuring that the bladder is filled with adequate urine volume. To comply with the simulation conditions during the treatment, daily cone-beam computed tomography (CBCT) images are acquired and controlled on a daily basis. The image-guided radiation therapy (IGRT) protocol provides a rigid fusion of the images acquired in the bunker with those collected from the simulation CT. For this study, we selected 23 patients with prostate adenocarcinoma (medium and low risk) treated with 40 fractions, with a daily dose of 2 Gy (80 Gy) at UPMC San Pietro FBF Advanced Radiotherapy Center in Rome, from October 2018 to May 2019. During the treatment, patients were placed in the supine position, with their arms on their chest and legs restrained by an immobilization device (ProSTEP™ Klarity). The offline ART workflow required pretreatment verifications, registration with the simulation images, and calculation of the rectum and bladder filling variations. The analysis was performed using the Velocity v4.0 software (Varian Medical System, Palo Alto CA). At the end of the Velocity-based software-automated process, the CT and CBCT images were used to generate an aCT (adaptive CT). Organs of interest were contoured on the aCT automatically. The Dice coefficient and the dispersion and distribution statistical indexes were taken into consideration to ensure accurate qualitative comparison. RESULTS Percentage dispersion of the rectum volume values was higher in Group A. Distribution of rectum volume variation percentage in Group A had an IQR = 5,55% (Q1=-4,06%; Q2= -1,13%; Q3= 1,49%), whereas Group B had an IQR= 4,24% (Q1= -2,50%; Q2= 2,09%; Q3= 1,75%). Percentage dispersion of the bladder volume values was higher in Group A. Distribution of bladder volume variation percentage in Group A had an IQR = 9,65% (Q1=-7,34%; Q2= -2,32%; Q3= 2,31%), whereas Group B had an IQR = 12,13% (Q1= -7,18%; Q2= -1,56%; Q3= 4,96%). The Dice coefficient in Group A showed an average daily superimposition of the bladder of 0,91 ± 0,07, whereas in Group B this was 0,87 ± 0,10. In both groups, the rectum volume had an average Dice coefficient of 0,89 ± 0,09. CONCLUSIONS The results show that the Dice coefficient can be useful to establish whether the volume localization can be superimposed to the simulation CT. Based on our practice, we suggest that the offline ART protocol should be verified over the first five therapy fractions, representing an adequate window to assess the need for replanning. Because this index does not consider the volumes but only the possibility of their geometric superimposition, we recommend checking the mean OAR volumes when using an offline ART workflow. This is particularly important for the bladder, which is more susceptible to this kind of change than variations in its localization.

The adult mammalian brain is mainly composed of mature neurons. A limited amount of stem cell-driven neurogenesis persists in postnatal life and is reduced in large-brained species. Another source of immature neurons in adult brains is cortical layer II. These cortical immature neurons (cINs) retain developmentally undifferentiated states in adulthood, though they are generated before birth. Here, the occurrence, distribution and cellular features of cINs were systematically studied in 12 diverse mammalian species spanning from small-lissencephalic to large-gyrencephalic brains. In spite of well-preserved morphological and molecular features, the distribution of cINs was highly heterogeneous, particularly in neocortex. While virtually absent in rodents, they are present in the entire neocortex of many other species and their linear density in cortical layer II generally increased with brain size. These findings suggest an evolutionary developmental mechanism for plasticity that varies among mammalian species, granting a reservoir of young cells for the cerebral cortex.

Editor's Note: this Article has been retracted; the Retraction Note is available at https://doi.org/10.1038/s41598-021-84101-3 .

Friedreich ataxia is an inherited neurodegenerative disease that leads to progressive disability. There is currently no effective treatment and patients die prematurely. The underlying genetic defect leads to reduced expression of the mitochondrial protein frataxin. Frataxin insufficiency causes mitochondrial dysfunction and ultimately cell death, particularly in peripheral sensory ganglia. There is an inverse correlation between the amount of residual frataxin and the severity of disease progression; therefore, therapeutic approaches aiming at increasing frataxin levels are expected to improve patients' conditions. We previously discovered that a significant amount of frataxin precursor is degraded by the ubiquitin/proteasome system before its functional mitochondrial maturation. We also provided evidence for the therapeutic potential of small molecules that increase frataxin levels by docking on the frataxin ubiquitination site, thus preventing frataxin ubiquitination and degradation. We called these compounds ubiquitin-competing molecules (UCM). By extending our search for effective UCM, we identified a set of new and more potent compounds that more efficiently promote frataxin accumulation. Here we show that these compounds directly interact with frataxin and prevent its ubiquitination. Interestingly, these UCM are not effective on the ubiquitin-resistant frataxin mutant, indicating their specific action on preventing frataxin ubiquitination. Most importantly, these compounds are able to promote frataxin accumulation and aconitase rescue in cells derived from patients, strongly supporting their therapeutic potential.

Testicular Germ Cell Tumors (TGCT) and patient-derived cell lines are extremely sensitive to cisplatin and other interstrand cross-link (ICL) inducing agents. Nevertheless, a subset of TGCTs are either innately resistant or acquire resistance to cisplatin during treatment. Understanding the mechanisms underlying TGCT sensitivity/resistance to cisplatin as well as the identification of novel strategies to target cisplatin-resistant TGCTs have major clinical implications. Herein, we have examined the proficiency of five embryonal carcinoma (EC) cell lines to repair cisplatin-induced ICLs. Using γH2AX staining as a marker of double strand break formation, we found that EC cell lines were either incapable of or had a reduced ability to repair ICL-induced damage. The defect correlated with reduced Homologous Recombination (HR) repair, as demonstrated by the reduction of RAD51 foci formation and by direct evaluation of HR efficiency using a GFP-reporter substrate. HR-defective tumors cells are known to be sensitive to the treatment with poly(ADP-ribose) polymerase (PARP) inhibitor. In line with this observation, we found that EC cell lines were also sensitive to PARP inhibitor monotherapy. The magnitude of sensitivity correlated with HR-repair reduced proficiency and with the expression levels and activity of PARP1 protein. In addition, we found that PARP inhibition strongly enhanced the response of the most resistant EC cells to cisplatin, by reducing their ability to overcome the damage. These results point to a reduced proficiency of HR repair as a source of sensitivity of ECs to ICL-inducing agents and PARP inhibitor monotherapy, and suggest that pharmacological inhibition of PARP can be exploited to target the stem cell component of the TGCTs (namely ECs) and to enhance the sensitivity of cisplatin-resistant TGCTs to standard treatments.