Citations

ABSTRACTBACKGROUND AND PURPOSEPathologic diagnosis is the gold standard in evaluating imaging measures developed as biomarkers for pathologically defined disorders. A brain MRI atlas representing autopsy‐sampled tissue can be used to directly compare imaging and pathology findings. Our objective was to develop a brain MRI atlas representing the cortical regions that are routinely sampled at autopsy for the diagnosis of Alzheimer's disease (AD).METHODSSubjects (n = 22; ages at death = 70‐95) with a range of pathologies and antemortem 3T MRI were included. Histology slides from 8 cortical regions sampled from the left hemisphere at autopsy guided the localization of the atlas regions of interest (ROIs) on each subject's antemortem 3D T1‐weighted MRI. These ROIs were then registered to a common template and combined to form one ROI representing the volume of tissue that was sampled by the pathologists. A subset of the subjects (n = 4; ages at death = 79‐95) had amyloid PET imaging. Density of β‐amyloid immunostain was quantified from the autopsy‐sampled regions in the 4 subjects using a custom‐designed ImageScope algorithm. Median uptake values were calculated in each ROI on the amyloid‐PET images.RESULTSWe found an association between β‐amyloid plaque density in 8 ROIs of the 4 subjects (total ROI n = 32) and median PiB SUVR (r2 = .64; P < .0001).CONCLUSIONSIn an atlas developed for imaging and pathologic correlation studies, we demonstrated that antemortem amyloid burden measured in the atlas ROIs on amyloid PET is strongly correlated with β‐amyloid density measured on histology. This atlas can be used in imaging and pathologic correlation studies.

SummaryNon‐Hodgkin lymphoma (NHL) is the third most common malignancy in children, adolescents and young adults (CAYA). NHL is a diverse set of diseases that arise at key regulatory checkpoints during B or T cell development in the bone marrow, germinal centre or thymus. While advances in the use of conventional cytotoxic agents have led to dramatic improvements in survival, these cures are associated with significant acute and long‐term toxicities. Moreover, the prognosis for CAYA patients with relapsed or refractory NHL remains dismal, with the vast majority dying of their disease. Thanks to a large number of candidate‐based biological studies, together with large‐scale sequencing efforts, there has been an explosion of knowledge regarding the molecular pathophysiology of B‐ and T‐NHL. This has ushered development of a flurry of novel therapeutic approaches that may simultaneously provide new hope for relapsed patients and an opportunity to reduce the therapeutic burden in newly diagnosed CAYA. Here we review a selection of the most promising new therapeutic approaches to these diseases. While the vast majority of these agents are untested in children, on‐going work from many cooperative groups will soon explore their use in paediatric disease, in hope of further improving outcomes while maximizing quality of life.

AbstractThe identification of a hexanucleotide repeat expansion in a non‐coding region of C9orf72 as a major cause of both frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) drastically changed the field of research on both of these conditions. Yet, despite the vast amount of work aimed at elucidating the molecular mechanisms underlying the role of this repeat in disease, the exact pathomechanisms are still unclear. A reduction in the expression of the C9orf72 gene is observed in patients, but a gain‐of‐function model is now preferred. The hexanucleotide repeat expansion forms RNA foci in the central nervous system (CNS) of repeat‐positive FTD and ALS patients, and these foci are believed to sequester RNA‐binding proteins (RBPs) and impair their function in RNA processing. At the same time, the repeat undergoes repeat‐associated non‐ATG translation to produce dipeptide repeat proteins that also form inclusions in the patient CNS. Studies from cells and flies suggest that these proteins may also be an important factor in the disease. Finally, the hexanucleotide repeat also induces the mislocalization and aggregation of TAR DNA‐binding protein 43 (TDP‐43) through an as yet unknown mechanism. This review covers the different potential pathogenic factors that have been put forth for C9orf72‐repeat‐associated FTD and ALS (C9‐FTD/ALS), while highlighting some remaining questions. image A repeat expansion in C9orf72 is a common cause of both frontal temporal dementia and amyotrophic lateral sclerosis. Although there is a decrease in C9orf72 expression in patients, this repeat is believed to induce disease primarily through an unknown gain‐of‐function mechanism involving the RNA, repeat‐associated non‐AUG translation, or both. This review summarizes and discusses current knowledge on C9orf72 repeat‐associated pathophysiology.This article is part of the Frontotemporal Dementia special issue.

ObjectiveWhite matter hyperintensities (WMHs) are areas of increased signal on T2‐weighted magnetic resonance imaging (MRI) scans that most commonly reflect small vessel cerebrovascular disease. Increased WMH volume is associated with risk and progression of Alzheimer's disease (AD). These observations are typically interpreted as evidence that vascular abnormalities play an additive, independent role contributing to symptom presentation, but not core features of AD. We examined the severity and distribution of WMH in presymptomatic PSEN1, PSEN2, and APP mutation carriers to determine the extent to which WMH manifest in individuals genetically determined to develop AD.MethodsThe study comprised participants (n = 299; age = 39.03 ± 10.13) from the Dominantly Inherited Alzheimer Network, including 184 (61.5%) with a mutation that results in AD and 115 (38.5%) first‐degree relatives who were noncarrier controls. We calculated the estimated years from expected symptom onset (EYO) by subtracting the affected parent's symptom onset age from the participant's age. Baseline MRI data were analyzed for total and regional WMH. Mixed‐effects piece‐wise linear regression was used to examine WMH differences between carriers and noncarriers with respect to EYO.ResultsMutation carriers had greater total WMH volumes, which appeared to increase approximately 6 years before expected symptom onset. Effects were most prominent for the parietal and occipital lobe, which showed divergent effects as early as 22 years before estimated onset.InterpretationAutosomal‐dominant AD is associated with increased WMH well before expected symptom onset. The findings suggest the possibility that WMHs are a core feature of AD, a potential therapeutic target, and a factor that should be integrated into pathogenic models of the disease. Ann Neurol 2016;79:929–939

Purpose Magnetic resonance elastography (MRE) is a rapidly growing noninvasive imaging technique for measuring tissue mechanical properties in vivo. Previous studies have compared two‐dimensional MRE measurements with material properties from dynamic mechanical analysis (DMA) devices that were limited in frequency range. Advanced DMA technology now allows broad frequency range testing, and three‐dimensional (3D) MRE is increasingly common. The purpose of this study was to compare 3D MRE stiffness measurements with those of DMA over a wide range of frequencies and shear stiffnesses. Methods 3D MRE and DMA were performed on eight different polyvinyl chloride samples over 20–205 Hz with stiffness between 3 and 23 kPa. Driving frequencies were chosen to create 1.1, 2.2, 3.3, 4.4, 5.5, and 6.6 effective wavelengths across the diameter of the cylindrical phantoms. Wave images were analyzed using direct inversion and local frequency estimation algorithm with the curl operator and compared with DMA measurements at each corresponding frequency. Samples with sufficient spatial resolution and with an octahedral shear strain signal‐to‐noise ratio > 3 were compared. Results Consistency between the two techniques was measured with the intraclass correlation coefficient (ICC) and was excellent with an overall ICC of 0.99. Conclusions 3D MRE and DMA showed excellent consistency over a wide range of frequencies and stiffnesses. Magn Reson Med 77:1184–1192, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.

Checkpoint blockade inhibitors have revolutionized the treatment of metastatic melanoma. Despite the success of these agents in improving the overall survival of patients with metastatic melanoma, not all patients achieve clinical benefit, leaving room for improvement. The presence of cutaneous metastases in patients with metastatic melanoma provides the unique opportunity to treat the cutaneous lesions with a local modality while simultaneously treating systemic disease with systemic therapy. Herein, we describe the treatment of two patients with both in-transit and metastatic melanoma with the combination of the topical toll-like receptor 7 agonist imiquimod with systemic ipilimumab. Both patients appeared to have progressed and developed new cutaneous and systemic metastases while on single agent ipilimumab only to respond when started on topical imiquimod. Both patients tolerated the combination of imiquimod and ipilimumab without serious adverse events, and both patients had excellent clinical responses. These cases provide a proof of principle of the possibility of the combination of toll-like receptor 7 agonists with immune checkpoint blockade inhibitors.

AbstractBackgroundOutcomes of neonates with congenital diaphragmatic hernia (CDH) are variable; reports are frequently limited to the experience of single tertiary care centres—a possible source of bias. Population‐based studies decrease survivor bias and provide additional insight into this high‐mortality condition. The objective of this study was to examine the incidence and outcomes of CDH in Croatia.MethodsAll cases of CDH in Croatia from 2001 through 2013 were ascertained from public health records. Overall and sex‐ and region‐specific incidence rates were calculated, and characteristics associated with 1‐year survival were assessed.ResultsWe identified 145 cases of CDH during the study period, for an incidence of 2.67 per 10 000 total births. The incidence did not differ by calendar year (P = 0.38) or geographic region (P = 0.67). There was a slightly higher incidence among males (rate ratio, 1.37, 95% CI 0.99, 1.91). The 1‐year survival rate was 33.1% for the entire cohort and 47.9% for liveborns who received any treatment at an intensive care unit. From multivariable analysis, survival was decreased in neonates with left CDH, liver up (odds ratio 0.1, 95% CI, 0.03, 0.4) and increased when treated in a centre with higher case volume (odds ratio 12.8, 95% CI, 2.2, 72.1).ConclusionsThe incidence of CDH in Croatia is within the range of previous reports. Survival was substantially higher in neonates treated in a centre with higher case volume, which suggests that centralisation of medical care for CDH may be warranted in Croatia.

Abstract Purpose: APOBEC3 DNA cytosine deaminase family members normally defend against viruses and transposons. However, deregulated APOBEC3 activity causes mutations in cancer. Because of broad expression profiles and varying mixtures of normal and cancer cells in tumors, including immune cell infiltration, it is difficult to determine where different APOBEC3s are expressed. Here, we ask whether correlations exist between APOBEC3 expression and T-cell infiltration in high-grade serous ovarian cancer (HGSOC), and assess whether these correlations have prognostic value. Experimental Design: Transcripts for APOBEC3G, APOBEC3B, and the T-cell markers, CD3D, CD4, CD8A, GZMB, PRF1, and RNF128 were quantified by RT-qPCR for a cohort of 354 HGSOC patients. Expression values were correlated with each other and clinical parameters. Two additional cohorts were used to extend HGSOC clinical results. Immunoimaging was used to colocalize APOBEC3G and the T-cell marker CD3. TCGA data extended expression analyses to additional cancer types. Results: A surprising positive correlation was found for expression of APOBEC3G and several T cell genes in HGSOC. Immunohistochemistry and immunofluorescent imaging showed protein colocalization in tumor-infiltrating T lymphocytes. High APOBEC3G expression correlated with improved outcomes in multiple HGSOC cohorts. TCGA data analyses revealed that expression of APOBEC3D and APOBEC3H also correlates with CD3D across multiple cancer types. Conclusions: Our results identify APOBEC3G as a new candidate biomarker for tumor-infiltrating T lymphocytes and favorable prognoses for HGSOC. Our data also highlight the complexity of the tumor environment with respect to differential APOBEC family gene expression in both tumor and surrounding normal cell types. Clin Cancer Res; 22(18); 4746–55. ©2016 AACR.