Genome organization around nuclear speckles drives mRNA splicing efficiency.

The nucleus is highly organized, such that factors involved in the transcription and processing of distinct classes of RNA are confined within specific nuclear bodies1,2. One example is the nuclear speckle, which is defined by high concentrations of protein and noncoding RNA regulators of pre-mRNA splicing3. What functional role, if any, speckles might play in the process of mRNA splicing is unclear4,5. Here we show that genes localized near nuclear speckles display higher spliceosome concentrations, increased spliceosome binding to their pre-mRNAs and higher co-transcriptional splicing levels than genes that are located farther from nuclear speckles. Gene organization around nuclear speckles is dynamic between cell types, and changes in speckle proximity lead to differences in splicing efficiency. Finally, directed recruitment of a pre-mRNA to nuclear speckles is sufficient to increase mRNA splicing levels. Together, our results integrate the long-standing observations of nuclear speckles with the biochemistry of mRNA splicing and demonstrate a crucial role for dynamic three-dimensional spatial organization of genomic DNA in driving spliceosome concentrations and controlling the efficiency of mRNA splicing.

Direct observation of the interconversion of normal and toxic forms of α-synuclein.

Here, we use single-molecule techniques to study the aggregation of α-synuclein, the protein whose misfolding and deposition is associated with Parkinson's disease. We identify a conformational change from the initially formed oligomers to stable, more compact proteinase-K-resistant oligomers as the key step that leads ultimately to fibril formation. The oligomers formed as a result of the structural conversion generate much higher levels of oxidative stress in rat primary neurons than do the oligomers formed initially, showing that they are more damaging to cells. The structural conversion is remarkably slow, indicating a high kinetic barrier for the conversion and suggesting that there is a significant period of time for the cellular protective machinery to operate and potentially for therapeutic intervention, prior to the onset of cellular damage. In the absence of added soluble protein, the assembly process is reversed and fibrils disaggregate to form stable oligomers, hence acting as a source of cytotoxic species.

Genetically dissecting the electron transport chain of a soil bacterium reveals a generalizable mechanism for biological phenazine-1-carboxylic acid oxidation.

The capacity for bacterial extracellular electron transfer via secreted metabolites is widespread in natural, clinical, and industrial environments. Recently, we discovered the biological oxidation of phenazine-1-carboxylic acid (PCA), the first example of biological regeneration of a naturally produced extracellular electron shuttle. However, it remained unclear how PCA oxidation was catalyzed. Here, we report the mechanism, which we uncovered by genetically perturbing the branched electron transport chain (ETC) of the soil isolate Citrobacter portucalensis MBL. Biological PCA oxidation is coupled to anaerobic respiration with nitrate, fumarate, dimethyl sulfoxide, or trimethylamine-N-oxide as terminal electron acceptors. Genetically inactivating the catalytic subunits for all redundant complexes for a given terminal electron acceptor abolishes PCA oxidation. In the absence of quinones, PCA can still donate electrons to certain terminal reductases, albeit much less efficiently. In C. portucalensis MBL, PCA oxidation is largely driven by flux through the ETC, which suggests a generalizable mechanism that may be employed by any anaerobically respiring bacterium with an accessible cytoplasmic membrane. This model is supported by analogous genetic experiments during nitrate respiration by Pseudomonas aeruginosa.

α-Carboxysome Size Is Controlled by the Disordered Scaffold Protein CsoS2.

Carboxysomes are protein microcompartments that function in the bacterial CO2 concentrating mechanism (CCM) to facilitate CO2 assimilation. To do so, carboxysomes assemble from thousands of constituent proteins into an icosahedral shell, which encapsulates the enzymes Rubisco and carbonic anhydrase to form structures typically > 100 nm and > 300 megadaltons. Although many of the protein interactions driving the assembly process have been determined, it remains unknown how size and composition are precisely controlled. Here, we show that the size of α-carboxysomes is controlled by the disordered scaffolding protein CsoS2. CsoS2 contains two classes of related peptide repeats that bind to the shell in a distinct fashion, and our data indicate that size is controlled by the relative number of these interactions. We propose an energetic and structural model wherein the two repeat classes bind at the junction of shell hexamers but differ in their preferences for the shell contact angles, and thus the local curvature. In total, this model suggests that a set of specific and repeated interactions between CsoS2 and shell proteins collectively achieve the large size and monodispersity of α-carboxysomes.

Loss of hepatic DRP1 exacerbates alcoholic hepatitis by inducing megamitochondria and mitochondrial maladaptation.

BACKGROUND AND AIMS: Increased megamitochondria formation and impaired mitophagy in hepatocytes have been linked to the pathogenesis of alcohol-associated liver disease (ALD). This study aims to determine the mechanisms by which alcohol consumption increases megamitochondria formation in the pathogenesis of ALD. APPROACH AND RESULTS: Human alcoholic hepatitis (AH) liver samples were used for electron microscopy, histology, and biochemical analysis. Liver-specific dynamin-related protein 1 (DRP1; gene name DNM1L, an essential gene regulating mitochondria fission ) knockout (L-DRP1 KO) mice and wild-type mice were subjected to chronic plus binge alcohol feeding. Both human AH and alcohol-fed mice had decreased hepatic DRP1 with increased accumulation of hepatic megamitochondria. Mechanistic studies revealed that alcohol feeding decreased DRP1 by impairing transcription factor EB-mediated induction of DNM1L . L-DRP1 KO mice had increased megamitochondria and decreased mitophagy with increased liver injury and inflammation, which were further exacerbated by alcohol feeding. Seahorse flux and unbiased metabolomics analysis showed alcohol intake increased mitochondria oxygen consumption and hepatic nicotinamide adenine dinucleotide (NAD + ), acylcarnitine, and ketone levels, which were attenuated in L-DRP1 KO mice, suggesting that loss of hepatic DRP1 leads to maladaptation to alcohol-induced metabolic stress. RNA-sequencing and real-time quantitative PCR analysis revealed increased gene expression of the cGAS-stimulator of interferon genes (STING)-interferon pathway in L-DRP1 KO mice regardless of alcohol feeding. Alcohol-fed L-DRP1 KO mice had increased cytosolic mtDNA and mitochondrial dysfunction leading to increased activation of cGAS-STING-interferon signaling pathways and liver injury. CONCLUSION: Alcohol consumption decreases hepatic DRP1 resulting in increased megamitochondria and mitochondrial maladaptation that promotes AH by mitochondria-mediated inflammation and cell injury.

A Pilot Study of Pembrolizumab Combined With Stereotactic Ablative Radiotherapy for Patients With Advanced or Metastatic Sarcoma.

OBJECTIVES: Immunotherapy with immune checkpoint inhibitors has shown only limited success in the management of metastatic soft tissue sarcoma. Overall response rates (ORR) with single agent pembrolizumab were 18% and median PFS was 18 weeks on the clinical trial SARC028. One strategy to improve the responses to immunotherapy is with stereotactic body radiation therapy (SBRT), which can enhance the antitumor CD8 T cell response through the release of tumor-specific antigens, potentially priming a more diverse class of T cell receptors. METHODS: This is a phase 0, pilot prospective study taking place at a single center with 2 arms. In Arm A, patients are treated with pembrolizumab 400 mg IV infusion on day 1 of a 42-day cycle. Stereotactic body radiation therapy (SBRT) is delivered in 1-5 fractions starting on C1D15-28 and given every other day. In Arm B, patients who have started an immune checkpoint inhibitor within 60 days are treated with SBRT in addition to the current therapy. RESULTS: In this study we outline testing the feasibility of adding SBRT to pembrolizumab. CONCLUSION: The ultimate goal of combination therapy is improved overall response, including tumors not treated with SBRT. This trial can be found registered online: NCT05488366.

Quantifying patients' preferences on tradeoffs between mortality risk and reduced need for target vessel revascularization for claudication.

BACKGROUND: In 2019, the US Food and Drug Administration issued a warning that symptomatic relief from claudication using paclitaxel-coated devices might be associated with an increase in mortality over 5 years. We designed a discrete-choice experiment (DCE) to quantify tradeoffs that patients would accept between a decreased risk of clinically driven target-vessel revascularization (CDTVR) and increased mortality risk. METHODS: Patients with claudication symptoms were recruited from seven medical centers to complete a web-based survey including eight DCE questions that presented pairs of hypothetical device profiles defined by varying risks of CDTVR and overall mortality at 2 and 5 years. Random-parameters logit models were used to estimate relative preference weights, from which the maximum-acceptable increase in 5-year mortality risk was derived. RESULTS: A total of 272 patients completed the survey. On average, patients would accept a device offering reductions in CDTVR risks from 30% to 10% at 2 years and from 40% to 30% at 5 years if the 5-year mortality risk was less than 12.6% (95% CI: 11.8-13.4%), representing a cut-point of 4.6 percentage points above a baseline risk of 8%. However, approximately 40% chose the device alternative with the lower 5-year mortality risk in seven (20.6%) or eight (18.0%) of the eight DCE questions regardless of the benefit offered. CONCLUSIONS: Most patients in the study would accept some incremental increase in 5-year mortality risk to reduce the 2-year and 5-year risks of CDTVR by 20 and 10 percentage points, respectively. However, significant patient-level variability in risk tolerance underscores the need for systematic approaches to support benefit-risk decision making.

Behavioral Impairments and Increased Risk of Cortical Atrophy Risk Scores Among World Trade Center Responders.

Objective: World Trade Center (WTC) responders are susceptible to both cognitive and neuropsychiatric impairments, particularly chronic posttraumatic stress disorder. The present study examined self-reported behavioral impairments in a sample of 732 WTC responders, 199 of whom were determined to have high risk of WTC-related cortical atrophy by an artificial neural network. Results: We found that responders at increased risk of cortical atrophy showed behavioral impairment across five domains: motivation, mood, disinhibition, empathy, and psychosis (14.6% vs 3.9% in the low-risk group; P = 3.90 × 10-7). Factor analysis models revealed that responders at high risk of cortical atrophy tended to have deficits generalized across all aspects of behavioral impairment with focal dysfunction in sensory psychosis. We additionally describe how relationships are modulated by exposure severity and pharmacological treatments. Discussion: Our findings suggest a potential link between sensory deficits and the development of cortical atrophy in WTC responders and may indicate symptoms consistent with a clinical portrait of parietal dominant Alzheimer's disease or a related dementia (ADRD). Results underscore the importance of investigating neuropsychiatric symptomatology in clinical evaluations of possible ADRD.

Patients on Antithrombotic Agents with Small Bowel Bleeding -Yield of Small Bowel Capsule Endoscopy and Subsequent Management.

BACKGROUND AND AIMS: Small bowel gastrointestinal bleeding (GIB) is associated with multiple blood transfusions, prolonged and/or multiple hospital admissions, utilization of significant healthcare resources, and negative effects on patient quality of life. There is a well-recognized association between antithrombotic medications and small bowel GIB. We aimed to identify the diagnostic yield of small bowel capsule endoscopy (SBCE) in patients on antithrombotic medications and the impact of SBCE on treatment course. METHODS: The electronic medical records of nineteen hundred eighty-six patients undergoing SBCE were retrospectively reviewed. RESULTS: The diagnostic yield for detecting stigmata of recent bleeding and/or actively bleeding lesions in SBCE was higher in patients that were on antiplatelet agents (21.6%), patients on anticoagulation (22.5%), and in patients that had their SBCE performed while they were inpatient (21.8%), when compared to the patients not on antiplatelet agents (12.1%), patients not on anticoagulation (13.5%), and with patients that had their SBCE performed in the outpatient setting (12%). Of 318 patients who had stigmata of recent bleeding and/or actively bleeding lesion(s) identified on SBCE, SBCE findings prompted endoscopic evaluation (small bowel enteroscopy, esophagogastroduodenoscopy (EGD), and/or colonoscopy) in 25.2%, with endoscopic hemostasis attempted in 52.5%. CONCLUSIONS: Our study, the largest conducted to date, emphasizes the importance of performing SBCE as part of the evaluation for suspected small bowel bleeding, particularly in patients taking antithrombotic therapy, and especially during their inpatient hospital stay.

First-in-human imaging using [11C]MDTC: a radiotracer targeting the cannabinoid receptor type 2.

PURPOSE: We report findings from the first-in-human study of [11C]MDTC, a radiotracer developed to image the cannabinoid receptor type 2 (CB2R) with positron emission tomography (PET). METHODS: Ten healthy adults were imaged according to a 90-min dynamic PET protocol after bolus intravenous injection of [11C]MDTC. Five participants also completed a second [11C]MDTC PET scan to assess test-retest reproducibility of receptor-binding outcomes. The kinetic behavior of [11C]MDTC in human brain was evaluated using tissue compartmental modeling. Four additional healthy adults completed whole-body [11C]MDTC PET/CT to calculate organ doses and the whole-body effective dose. RESULTS: [11C]MDTC brain PET and [11C]MDTC whole-body PET/CT was well-tolerated. A murine study found evidence of brain-penetrant radiometabolites. The model of choice for fitting the time activity curves (TACs) across brain regions of interest was a three-tissue compartment model that includes a separate input function and compartment for the brain-penetrant metabolites. Regional distribution volume (VT) values were low, indicating low CB2R expression in the brain. Test-retest reliability of VT demonstrated a mean absolute variability of 9.91%. The measured effective dose of [11C]MDTC was 5.29 µSv/MBq. CONCLUSION: These data demonstrate the safety and pharmacokinetic behavior of [11C]MDTC with PET in healthy human brain. Future studies identifying radiometabolites of [11C]MDTC are recommended before applying [11C]MDTC PET to assess the high expression of the CB2R by activated microglia in human brain.

De-Escalation Treatment for Human Papillomavirus-Related Oropharyngeal Cancer: Questions for Practical Consideration.

Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (SCC), which accounts for an increasing proportion of all head and neck cancers, represents a specific entity with distinct clinical and molecular characteristics. It is now firmly established that patients with HPV-positive oropharyngeal SCC have a significantly improved prognosis because this variant has exquisite radiosensitivity compared with HPV-negative oropharyngeal SCC; thus, it can be targeted with de-escalated approaches using reduced doses of radiation and/or chemotherapy. The overriding goal of de-escalation is to maintain the high cure and survival rates associated with traditional approaches while reducing the incidence of both short- and long-term toxicity. Although the exact reason for the improved radiosensitivity of HPV-positive oropharyngeal carcinoma is unclear, prospective studies have now been published demonstrating that de-escalated radiation can successfully maintain high rates of cure and preserve the quality of life for appropriately selected patients with this disease. However, these studies have been complicated by such factors as the relatively limited sample sizes, as well as the variability in treatment, inclusion criteria, and follow-up. How treatment paradigms will evolve, particularly in the era of precision medicine, is a provocative question and is the subject of this review.

Lysine Ubiquitylation Drives Rhodopsin Protein Turnover.

Rhodopsin is a G-protein-coupled receptor that is specifically and abundantly expressed in rod photoreceptors. Over 150 rhodopsin mutations cause autosomal dominant retinitis pigmentosa (adRP). The most common mutation in the United States is the conversion of proline to histidine at position 23 (P23H) in the N-terminal domain of rhodopsin. We previously found that P23H rhodopsin was misfolded, ubiquitinylated, and rapidly degraded. Here, we investigated the role of lysine residues on P23H rhodopsin ubiquitinylation and turnover. We transfected HEK293 cells with a P23H human rhodopsin construct where all 11 lysine residues were mutated to arginine (K-null P23H). We found that the K-null P23H rhodopsin was significantly less ubiquitylated than intact P23H rhodopsin. We found that K-null P23H protein turnover was significantly slower compared to P23H rhodopsin through cycloheximide chase analysis. Finally, we also generated a wild-type rhodopsin construct where all lysines were converted to arginine and found significantly reduced ubiquitylation. Our findings identify ubiquitinylation of lysine residues as an important posttranslational modification involved in P23H rhodopsin protein degradation.

A survey of pain physicians: Needlesticks injuries.

OBJECTIVE: To investigate and characterize the incidence of needlestick injuries (NSI) in a sample of practicing pain medicine physicians, with the ultimate goal of aiding to prevent these injuries by raising awareness of their prevalence. DESIGN: A cross-sectional research survey. SETTING: A REDCap survey was emailed to physicians who had membership to the American Academy of Pain Medicine. SUBJECTS: Eligibility criteria included physicians who were actively practicing and identified as pain physicians who participated in procedures with needlesticks or sharps. METHODS: Basic demographics without identifiers were collected, including practice setting, years in practice, and training type. Respondents were asked to estimate the number of sharps-involved procedure days per week and per day. They were then asked to estimate the number of NSIs they sustained since completing training and in the past year. RESULTS: A total of 430 surveys were opened by email by potential participants, of which 124 responded (response rate 29%). Data from a total of 109 respondents that met inclusion criteria were included. Roughly 60% of respondents reported at least one NSI since completing training and approximately one-third had sustained more than three NSIs. In the last year, roughly 19% of providers reported at least one needlestick injury. The number of NSIs reported by providers since completing training was not significantly associated with practice setting, the number of procedure days per week, or the number of sharps-involved procedures per day. There was a significant relationship between years post-training and number of NSIs since completing training, with providers with more years post-training reporting higher incidences of NSIs (p < 0.0005). The number of NSIs since completing training and the number of NSIs were also associated, with providers that had sustained a greater number of total NSIs reporting a higher incidence of NSIs within the last year (p < 0.0005). CONCLUSIONS: This study characterizes NSIs in a population of pain medicine physicians. These data warrant caution and will hopefully raise awareness amongst providers.

Low-dose Ketamine Infusion for Pediatric Hematology/Oncology Patients: Case Series and Literature Review.

Management of refractory pain in pediatric sickle cell disease (SCD) and oncology is reliant on opioids though high opioid dosing increases side effects and tachyphylaxis. We introduced low-dose ketamine infusion (LDKI) to our inpatient unit to determine if LDKI was tolerable. We subsequently hypothesized that LDKI would improve pain scores. We reviewed inpatients from LDKI initiation in March 2014 through October 2017, with the day before LDKI initiation compared with the day of LDKI initiation and 2 subsequent days. For patients with SCD, the LDKI admission was compared with up to 3 admissions in the prior year for a vaso-occlusive event. Nineteen patients (12 oncology, 7 SCD) with a median age of 14.6 years received LDKI for a median of 6 days at a median initial dose of 0.06 mg/kg/h (1.1 µg/kg/min). There was no change in pain scores or opioid utilization when comparing the day before LDKI initiation with subsequent days. No patient discontinued LDKI because of intolerability. For patients with SCD, there was a median 32% reduction in cumulative pain scores when comparing the LDKI admission with prior admissions. LDKI is well tolerated for refractory pediatric cancer-related and sickle cell-related pain.

Intra-Articular Platelet Rich Plasma vs Corticosteroid Injections for Sacroiliac Joint Pain: A Double-Blinded, Randomized Clinical Trial.

OBJECTIVE: Using stringent inclusion criteria, a double-blinded study protocol, and fluoroscopically guided injections, we compare intra-articular sacroiliac joint platelet-rich plasma injections with intra-articular steroids. DESIGN: Double-blind, randomized controlled trial. SETTING: Two large university-based interdisciplinary spine centers. SUBJECTS: A total of 26 patients with a positive diagnostic block (>80% relief). METHODS: Subjects who had a positive diagnostic block were randomized to undergo either a fluoroscopically guided intra-articular injection of steroid or a platelet-rich plasma injection. Follow-up was at 1 month, 3 months, and 6 months. Outcomes included level of pain, as indicated on a 0- to 100-mm numeric pain rating scale, and functional disability score, obtained via the Oswestry Disability Index (ODI). RESULTS: At 1, 3, and 6 months, both groups improved; however, subjects who received steroid injections reported lower pain scores than did subjects who received platelet-rich plasma. Using categorical data, we observed significantly more responders (defined as pain scores that improved by 50% or more from baseline) at 1 and 3 months in the group who received steroids than in the group who received platelet-rich plasma. CONCLUSION: Although both groups showed improvements in pain and function, the steroid group had significantly greater response and significantly more responders than did the platelet-rich plasma group.

Nivolumab plus Ipilimumab versus Sunitinib in Advanced Renal-Cell Carcinoma.

BACKGROUND: Nivolumab plus ipilimumab produced objective responses in patients with advanced renal-cell carcinoma in a pilot study. This phase 3 trial compared nivolumab plus ipilimumab with sunitinib for previously untreated clear-cell advanced renal-cell carcinoma. METHODS: We randomly assigned adults in a 1:1 ratio to receive either nivolumab (3 mg per kilogram of body weight) plus ipilimumab (1 mg per kilogram) intravenously every 3 weeks for four doses, followed by nivolumab (3 mg per kilogram) every 2 weeks, or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The coprimary end points were overall survival (alpha level, 0.04), objective response rate (alpha level, 0.001), and progression-free survival (alpha level, 0.009) among patients with intermediate or poor prognostic risk. RESULTS: A total of 1096 patients were assigned to receive nivolumab plus ipilimumab (550 patients) or sunitinib (546 patients); 425 and 422, respectively, had intermediate or poor risk. At a median follow-up of 25.2 months in intermediate- and poor-risk patients, the 18-month overall survival rate was 75% (95% confidence interval [CI], 70 to 78) with nivolumab plus ipilimumab and 60% (95% CI, 55 to 65) with sunitinib; the median overall survival was not reached with nivolumab plus ipilimumab versus 26.0 months with sunitinib (hazard ratio for death, 0.63; P<0.001). The objective response rate was 42% versus 27% (P<0.001), and the complete response rate was 9% versus 1%. The median progression-free survival was 11.6 months and 8.4 months, respectively (hazard ratio for disease progression or death, 0.82; P=0.03, not significant per the prespecified 0.009 threshold). Treatment-related adverse events occurred in 509 of 547 patients (93%) in the nivolumab-plus-ipilimumab group and 521 of 535 patients (97%) in the sunitinib group; grade 3 or 4 events occurred in 250 patients (46%) and 335 patients (63%), respectively. Treatment-related adverse events leading to discontinuation occurred in 22% and 12% of the patients in the respective groups. CONCLUSIONS: Overall survival and objective response rates were significantly higher with nivolumab plus ipilimumab than with sunitinib among intermediate- and poor-risk patients with previously untreated advanced renal-cell carcinoma. (Funded by Bristol-Myers Squibb and Ono Pharmaceutical; CheckMate 214 ClinicalTrials.gov number, NCT02231749 .).

Polymicrogyria is Associated With Pathogenic Variants in PTEN.

OBJECTIVE: Congenital structural brain malformations have been described in patients with pathogenic phosphatase and tensin homologue (PTEN) variants, but the frequency of cortical malformations in patients with PTEN variants and their impact on clinical phenotype are not well understood. Our goal was to systematically characterize brain malformations in patients with PTEN variants and assess the relevance of their brain malformations to clinical presentation. METHODS: We systematically searched a local radiology database for patients with PTEN variants who had available brain magnetic resonance imaging (MRI). The MRI scans were reviewed systematically for cortical abnormalities. We reviewed electroencephalogram (EEG) data and evaluated the electronic medical record for evidence of epilepsy and developmental delay. RESULTS: In total, we identified 22 patients with PTEN pathogenic variants for which brain MRIs were available (age range 0.4-17 years). Twelve among these 22 patients (54%) had polymicrogyria (PMG). Variants associated with PMG or atypical gyration encoded regions of the phosphatase or C2 domains of PTEN. Interestingly, epilepsy was present in only 2 of the 12 patients with PMG. We found a trend toward higher rates of global developmental delay (GDD), intellectual disability (ID), and motor delay in individuals with cortical abnormalities, although cohort size limited statistical significance. INTERPRETATION: Malformations of cortical development, PMG in particular, represent an under-recognized phenotype associated with PTEN pathogenic variants and may have an association with cognitive and motor delays. Epilepsy was infrequent compared to the previously reported high risk of epilepsy in patients with PMG. ANN NEUROL 2020;88:1153-1164.

Measuring Patient Preferences at the FDA Center for Devices and Radiological Health: Reflections and Projections.

OBJECTIVES: Patient preference information (PPI) is a way to incorporate the patient voice in the evaluation of medical devices. The US Food and Drug Administration (FDA) Center for Devices and Radiological Health (CDRH) has been working to encourage the voluntary inclusion of PPI throughout the medical device lifecycle for nearly a decade. This article reflects CDRH's efforts to encourage collection of PPI and offers perspectives on the future of PPI in the evaluation of medical devices. METHODS: CDRH regulatory guidance, public meetings, and collaborations relating to PPI were explored. RESULTS: Since 2012 when CDRH issued guidance on how PPI can be used as scientific evidence in the benefit-risk regulatory submission, CDRH has issued 5 subsequent guidance documents expanding on the use of PPI in medical device evaluations. CDRH remains committed to advancing the science and application of PPI in the medical device ecosystem through many collaborations with professional organizations, patient advocacy groups, and academic institutions. By hosting and actively participating in multiple scientific and regulatory public meetings and conferences, CDRH fosters a continuous learning environment where the experience of using PPI in regulatory submissions can be shared. A September 2020 meeting cosponsored by FDA and International Society for Pharmacoeconomics and Outcomes Research (ISPOR) discussed the state of PPI in regulatory applications and beyond. CONCLUSION: This article describes these pivotal events that have helped to increase the use of PPI in medical device evaluation as well as discusses future applications of PPI.

Novel PHOX2B germline mutation in childhood medulloblastoma: a case report.

BACKGROUND: Medulloblastoma is an aggressive brain tumor mostly found in children, few studies on pathogenic germline mutations predisposing this disease was reported. CASE PRESENTATION: We present an 11-year-old male with medulloblastoma, who harbors a de novo PHOX2B germline mutation as detected by whole exome sequencing (WES). Family history was negative. Sanger sequencing confirmed this mutation in peripheral blood, hair bulbs, urine and saliva. Identification of novel germline mutations is beneficial for childhood cancer screening. CONCLUSIONS: This case revealed a de novo PHOX2B germline mutation as a potential cause of medulloblastoma in a child and suggests familial germline variant screening is useful when an affected family is considering having a second child.

First-Line Nivolumab in Stage IV or Recurrent Non-Small-Cell Lung Cancer.

BACKGROUND: Nivolumab has been associated with longer overall survival than docetaxel among patients with previously treated non-small-cell lung cancer (NSCLC). In an open-label phase 3 trial, we compared first-line nivolumab with chemotherapy in patients with programmed death ligand 1 (PD-L1)-positive NSCLC. METHODS: We randomly assigned, in a 1:1 ratio, patients with untreated stage IV or recurrent NSCLC and a PD-L1 tumor-expression level of 1% or more to receive nivolumab (administered intravenously at a dose of 3 mg per kilogram of body weight once every 2 weeks) or platinum-based chemotherapy (administered once every 3 weeks for up to six cycles). Patients receiving chemotherapy could cross over to receive nivolumab at the time of disease progression. The primary end point was progression-free survival, as assessed by means of blinded independent central review, among patients with a PD-L1 expression level of 5% or more. RESULTS: Among the 423 patients with a PD-L1 expression level of 5% or more, the median progression-free survival was 4.2 months with nivolumab versus 5.9 months with chemotherapy (hazard ratio for disease progression or death, 1.15; 95% confidence interval [CI], 0.91 to 1.45; P=0.25), and the median overall survival was 14.4 months versus 13.2 months (hazard ratio for death, 1.02; 95% CI, 0.80 to 1.30). A total of 128 of 212 patients (60%) in the chemotherapy group received nivolumab as subsequent therapy. Treatment-related adverse events of any grade occurred in 71% of the patients who received nivolumab and in 92% of those who received chemotherapy. Treatment-related adverse events of grade 3 or 4 occurred in 18% of the patients who received nivolumab and in 51% of those who received chemotherapy. CONCLUSIONS: Nivolumab was not associated with significantly longer progression-free survival than chemotherapy among patients with previously untreated stage IV or recurrent NSCLC with a PD-L1 expression level of 5% or more. Overall survival was similar between groups. Nivolumab had a favorable safety profile, as compared with chemotherapy, with no new or unexpected safety signals. (Funded by Bristol-Myers Squibb and others; CheckMate 026 ClinicalTrials.gov number, NCT02041533 .).