The spectrum of disease and tau pathology of nodding syndrome in Uganda.

Nodding syndrome is an enigmatic recurrent epidemic neurologic disease that affects children in East Africa. The illness begins with vertical nodding of the head and can progress to grand mal seizures and death after several years. The most recent outbreak of nodding syndrome occurred in northern Uganda. We now describe the clinicopathologic spectrum of nodding syndrome in northern Uganda. The neuropathologic findings of 16 children or young adults with fatal nodding syndrome were correlated with the onset, duration and progression of their neurological illness. The affected individuals ranged in age from 14 to 25 years at the time of death with a duration of illness ranging from 6-15 years. All 16 cases had chronic seizures. In 10 cases, detailed clinical histories were available and showed that three individuals had a clinical course that was predominantly characterized by epilepsy, whereas the other seven individuals had progressive cognitive, behavioural and motor decline, in addition to epilepsy. The main neuropathologic findings included: tau pathology (16/16 cases), cerebellar degeneration (11/16 cases) and white matter degeneration (7/16 cases). The tau pathology was characterized by filamentous tau-positive deposits in the form of neurofibrillary tangles, pre-tangles and dot-like grains and threads in the neuropil. All cases showed some degree of tau pathology in the neocortex and in the locus coeruleus with frequent involvement of the substantia nigra and tegmental nuclei and lesser involvement of other grey matter sites, but there was a lack of glial tau pathology. The tau pathology in the neocortex showed a multifocal superficial laminar pattern. We conclude that nodding syndrome is a clinicopathological entity associated consistently with tau pathology, but our observations did not establish the cause of the disease, or an explanation for the tau pathology.

Combined cytotoxic and immune-stimulatory gene therapy for primary adult high-grade glioma: a phase 1, first-in-human trial.

BACKGROUND: High-grade gliomas have a poor prognosis and do not respond well to treatment. Effective cancer immune responses depend on functional immune cells, which are typically absent from the brain. This study aimed to evaluate the safety and activity of two adenoviral vectors expressing HSV1-TK (Ad-hCMV-TK) and Flt3L (Ad-hCMV-Flt3L) in patients with high-grade glioma. METHODS: In this dose-finding, first-in-human trial, treatment-naive adults aged 18-75 years with newly identified high-grade glioma that was evaluated per immunotherapy response assessment in neuro-oncology criteria, and a Karnofsky Performance Status score of 70 or more, underwent maximal safe resection followed by injections of adenoviral vectors expressing HSV1-TK and Flt3L into the tumour bed. The study was conducted at the University of Michigan Medical School, Michigan Medicine (Ann Arbor, MI, USA). The study included six escalating doses of viral particles with starting doses of 1×1010 Ad-hCMV-TK viral particles and 1×109 Ad-hCMV-Flt3L viral particles (cohort A), and then 1×1011 Ad-hCMV-TK viral particles and 1×109 Ad-hCMV-Flt3L viral particles (cohort B), 1×1010 Ad-hCMV-TK viral particles and 1×1010 Ad-hCMV-Flt3L viral particles (cohort C), 1×1011 Ad-hCMV-TK viral particles and 1×1010 Ad-hCMV-Flt3L viral particles (cohort D), 1×1010 Ad-hCMV-TK viral particles and 1×1011 Ad-hCMV-Flt3L viral particles (cohort E), and 1×1011 Ad-hCMV-TK viral particles and 1×1011 Ad-hCMV-Flt3L viral particles (cohort F) following a 3+3 design. Two 1 mL tuberculin syringes were used to deliver freehand a mix of Ad-hCMV-TK and Ad-hCMV-Flt3L vectors into the walls of the resection cavity with a total injection of 2 mL distributed as 0·1 mL per site across 20 locations. Subsequently, patients received two 14-day courses of valacyclovir (2 g orally, three times per day) at 1-3 days and 10-12 weeks after vector administration and standad upfront chemoradiotherapy. The primary endpoint was the maximum tolerated dose of Ad-hCMV-Flt3L and Ad-hCMV-TK. Overall survival was a secondary endpoint. Recruitment is complete and the trial is finished. The trial is registered with ClinicalTrials.gov, NCT01811992. FINDINGS: Between April 8, 2014, and March 13, 2019, 21 patients were assessed for eligibility and 18 patients with high-grade glioma were enrolled and included in the analysis (three patients in each of the six dose cohorts); eight patients were female and ten were male. Neuropathological examination identified 14 (78%) patients with glioblastoma, three (17%) with gliosarcoma, and one (6%) with anaplastic ependymoma. The treatment was well-tolerated, and no dose-limiting toxicity was observed. The maximum tolerated dose was not reached. The most common serious grade 3-4 adverse events across all treatment groups were wound infection (four events in two patients) and thromboembolic events (five events in four patients). One death due to an adverse event (respiratory failure) occurred but was not related to study treatment. No treatment-related deaths occurred during the study. Median overall survival was 21·3 months (95% CI 11·1-26·1). INTERPRETATION: The combination of two adenoviral vectors demonstrated safety and feasibility in patients with high-grade glioma and warrants further investigation in a phase 1b/2 clinical trial. FUNDING: Funded in part by Phase One Foundation, Los Angeles, CA, The Board of Governors at Cedars-Sinai Medical Center, Los Angeles, CA, and The Rogel Cancer Center at The University of Michigan.

TDP-43 stabilizes G3BP1 mRNA: relevance to amyotrophic lateral sclerosis/frontotemporal dementia.

TDP-43 nuclear depletion and concurrent cytoplasmic accumulation in vulnerable neurons is a hallmark feature of progressive neurodegenerative proteinopathies such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Cellular stress signalling and stress granule dynamics are now recognized to play a role in ALS/FTD pathogenesis. Defective stress granule assembly is associated with increased cellular vulnerability and death. Ras-GAP SH3-domain-binding protein 1 (G3BP1) is a critical stress granule assembly factor. Here, we define that TDP-43 stabilizes G3BP1 transcripts via direct binding of a highly conserved cis regulatory element within the 3' untranslated region. Moreover, we show in vitro and in vivo that nuclear TDP-43 depletion is sufficient to reduce G3BP1 protein levels. Finally, we establish that G3BP1 transcripts are reduced in ALS/FTD patient neurons bearing TDP-43 cytoplasmic inclusions/nuclear depletion. Thus, our data indicate that, in ALS/FTD, there is a compromised stress granule response in disease-affected neurons due to impaired G3BP1 mRNA stability caused by TDP-43 nuclear depletion. These data implicate TDP-43 and G3BP1 loss of function as contributors to disease.

A C6orf10/LOC101929163 locus is associated with age of onset in C9orf72 carriers.

The G4C2-repeat expansion in C9orf72 is the most common known cause of amyotrophic lateral sclerosis and frontotemporal dementia. The high phenotypic heterogeneity of C9orf72 patients includes a wide range in age of onset, modifiers of which are largely unknown. Age of onset could be influenced by environmental and genetic factors both of which may trigger DNA methylation changes at CpG sites. We tested the hypothesis that age of onset in C9orf72 patients is associated with some common single nucleotide polymorphisms causing a gain or loss of CpG sites and thus resulting in DNA methylation alterations. Combined analyses of epigenetic and genetic data have the advantage of detecting functional variants with reduced likelihood of false negative results due to excessive correction for multiple testing in genome-wide association studies. First, we estimated the association between age of onset in C9orf72 patients (n = 46) and the DNA methylation levels at all 7603 CpG sites available on the 450 k BeadChip that are mapped to common single nucleotide polymorphisms. This was followed by a genetic association study of the discovery (n = 144) and replication (n = 187) C9orf72 cohorts. We found that age of onset was reproducibly associated with polymorphisms within a 124.7 kb linkage disequilibrium block tagged by top-significant variation, rs9357140, and containing two overlapping genes (LOC101929163 and C6orf10). A meta-analysis of all 331 C9orf72 carriers revealed that every A-allele of rs9357140 reduced hazard by 30% (P = 0.0002); and the median age of onset in AA-carriers was 6 years later than GG-carriers. In addition, we investigated a cohort of C9orf72 negative patients (n = 2634) affected by frontotemporal dementia and/or amyotrophic lateral sclerosis; and also found that the AA-genotype of rs9357140 was associated with a later age of onset (adjusted P = 0.007 for recessive model). Phenotype analyses detected significant association only in the largest subgroup of patients with frontotemporal dementia (n = 2142, adjusted P = 0.01 for recessive model). Gene expression studies of frontal cortex tissues from 25 autopsy cases affected by amyotrophic lateral sclerosis revealed that the G-allele of rs9357140 is associated with increased brain expression of LOC101929163 (a non-coding RNA) and HLA-DRB1 (involved in initiating immune responses), while the A-allele is associated with their reduced expression. Our findings suggest that carriers of the rs9357140 GG-genotype (linked to an earlier age of onset) might be more prone to be in a pro-inflammatory state (e.g. by microglia) than AA-carriers. Further, investigating the functional links within the C6orf10/LOC101929163/HLA-DRB1 pathway will be critical to better define age-dependent pathogenesis of frontotemporal dementia and amyotrophic lateral sclerosis.

Jump from pre-mutation to pathologic expansion in C9orf72.

An expanded G4C2 repeat in C9orf72 represents the most common known genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). However, the lower limit for pathological expansions is unknown (the suggested cutoff is 30 repeats). It has been proposed that the expansion might have occurred only once in human history and subsequently spread throughout the population. However, our present findings support a hypothesis of multiple origins for the expansion. We report a British-Canadian family in whom a ∼70-repeat allele from the father (unaffected by ALS or FTLD at age 89 years) expanded during parent-offspring transmission and started the first generation affected by ALS (four children carry an ∼1,750-repeat allele). Epigenetic and RNA-expression analyses further discriminated the offspring's large expansions (which were methylated and associated with reduced C9orf72 expression) from the ∼70-repeat allele (which was unmethylated and associated with upregulation of C9orf72). Moreover, RNA foci were only detected in fibroblasts from offspring with large expansions, but not in the father, who has the ∼70-repeat allele. All family members with expansions were found to have an ancient known risk haplotype, although it was inherited on a unique 5-Mb genetic backbone. We conclude that small expansions (e.g., 70 repeats) might be considered "pre-mutations" to reflect their propensity to expand in the next generation. Follow-up studies might help explain the high frequency of ALS- or FTLD-affected individuals with an expansion but without a familial history (e.g., 21% among Finnish ALS subjects).

Nodding syndrome in Uganda is a tauopathy.

Nodding syndrome is an epidemic neurologic disorder of unknown cause that affects children in the subsistence-farming communities of East Africa. We report the neuropathologic findings in five fatal cases (13-18 years of age at death) of nodding syndrome from the Acholi people in northern Uganda. Neuropathologic examination revealed tau-immunoreactive neuronal neurofibrillary tangles, pre-tangles, neuropil threads, and dot-like lesions involving the cerebral cortex, subcortical nuclei and brainstem. There was preferential involvement of the frontal and temporal lobes in a patchy distribution, mostly involving the crests of gyri and the superficial cortical lamina. The mesencephalopontine tegmental nuclei, substantia nigra, and locus coeruleus revealed globose neurofibrillary tangles and threads. We conclude that nodding syndrome is a tauopathy and may represent a newly recognized neurodegenerative disease.

Downregulation of exosomal miR-204-5p and miR-632 as a biomarker for FTD: a GENFI study.

OBJECTIVE: To determine whether exosomal microRNAs (miRNAs) in cerebrospinal fluid (CSF) of patients with frontotemporal dementia (FTD) can serve as diagnostic biomarkers, we assessed miRNA expression in the Genetic Frontotemporal Dementia Initiative (GENFI) cohort and in sporadic FTD. METHODS: GENFI participants were either carriers of a pathogenic mutation in progranulin, chromosome 9 open reading frame 72 or microtubule-associated protein tau or were at risk of carrying a mutation because a first-degree relative was a known symptomatic mutation carrier. Exosomes were isolated from CSF of 23 presymptomatic and 15 symptomatic mutation carriers and 11 healthy non-mutation carriers. Expression of 752 miRNAs was measured using quantitative PCR (qPCR) arrays and validated by qPCR using individual primers. MiRNAs found differentially expressed in symptomatic compared with presymptomatic mutation carriers were further evaluated in a cohort of 17 patients with sporadic FTD, 13 patients with sporadic Alzheimer's disease (AD) and 10 healthy controls (HCs) of similar age. RESULTS: In the GENFI cohort, miR-204-5p and miR-632 were significantly decreased in symptomatic compared with presymptomatic mutation carriers. Decrease of miR-204-5p and miR-632 revealed receiver operator characteristics with an area of 0.89 (90% CI 0.79 to 0.98) and 0.81 (90% CI 0.68 to 0.93), respectively, and when combined an area of 0.93 (90% CI 0.87 to 0.99). In sporadic FTD, only miR-632 was significantly decreased compared with AD and HCs. Decrease of miR-632 revealed an area of 0.90 (90% CI 0.81 to 0.98). CONCLUSIONS: Exosomal miR-204-5p and miR-632 have potential as diagnostic biomarkers for genetic FTD and miR-632 also for sporadic FTD.

DNA methylation age-acceleration is associated with disease duration and age at onset in C9orf72 patients.

The repeat expansion in C9orf72 is the most common cause of amyotrophic lateral sclerosis and frontotemporal dementia. C9orf72 patients present with a wide range in disease duration and age of onset. The strongest risk factor for both syndromes is aging, which was linked to DNA methylation (DNAm) age based on the cumulative assessment of the methylation levels of 353 CpGs included on the genome-wide 450k BeadChip. DNAm age may reflect biological age better than chronological age. We conducted a genome-wide blood DNA methylation study of 46 unrelated C9orf72 patients. After correction for multiple testing, none of the CpGs demonstrated association between its methylation level and disease duration or age of onset. However, we detected a significant reverse correlation of DNAm age-acceleration with disease duration and age of onset, suggesting that for every 5-year increase in DNAm age-acceleration there is a 3.2-year earlier age of onset and 1.5-year shorter disease duration. The significant correlations remain after adjusting for gender, TMEM106B genotypes, disease phenotype and C9orf72 5'CpG island methylation status. A similar trend was observed for the blood DNA of affected members of an extended C9orf72 family; and tissues from the central nervous system of C9orf72 autopsy cases. For instance, regression analysis suggested that a 5-year increase in DNAm age-acceleration is linked to an earlier age of onset by 4.7 or 5.5 years for frontal cortex or spinal cord, respectively. Blood DNAm age may be a useful biomarker for biological age, because blood DNAm age-acceleration was similar to all investigated brain tissues, except for cerebellum that ages more slowly. In conclusion, DNA methylation analysis of C9orf72 patients revealed that increased DNAm age-acceleration is associated with a more severe disease phenotype with a shorter disease duration and earlier age of onset.

Molecular characterization reveals NF1 deletions and FGFR1-activating mutations in a pediatric spinal oligodendroglioma.

Pediatric spinal oligodendrogliomas are rare and aggressive tumors. They do not share the same molecular features of adult oligodendroglioma, and no previous reports have examined the molecular features of pediatric spinal oligodendroglioma. We present the case of a child with a recurrent spinal anaplastic oligodendroglioma. We performed whole exome (paired tumor and germline DNA) and transcriptome (tumor RNA) sequencing, which revealed somatic mutations in NF1 and FGFR1. These data allowed us to explore potential personalized therapies for this patient and expose molecular drivers that may be involved in similar cases.

Isoform-specific antibodies reveal distinct subcellular localizations of C9orf72 in amyotrophic lateral sclerosis.

OBJECTIVE: A noncoding hexanucleotide repeat expansion in C9orf72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). It has been reported that the repeat expansion causes a downregulation of C9orf72 transcripts, suggesting that haploinsufficiency may contribute to disease pathogenesis. Two protein isoforms are generated from three alternatively spliced transcripts of C9orf72; a long form (C9-L) and a short form (C9-S), and their function(s) are largely unknown owing to lack of specific antibodies. METHODS: To investigate C9orf72 protein properties, we developed novel antibodies that recognize either C9-L or C9-S. Multiple techniques, including Western blot, immunohistochemistry, and coimmunoprecipitation, were used to determine the expression levels and subcellular localizations of C9-L and C9-S. RESULTS: Investigation of expression of C9-L and C9-S demonstrated distinct biochemical profiles, region-specific changes, and distinct subcellular localizations in ALS tissues. In particular, C9-L antibody exhibited a diffuse cytoplasmic staining in neurons and labeled large speckles in cerebellar Purkinje cells. In contrast, C9-S antibody gave very specific labeling of the nuclear membrane in healthy neurons, with apparent relocalization to the plasma membrane of diseased motor neurons in ALS. Coimmunoprecipitation experiments revealed an interaction of the C9-isoforms with both Importin ß1 and Ran-GTPase, components of the nuclear pore complex. INTERPRETATION: Using these antibodies, we have shown that C9orf72 may be involved in nucleocytoplasmic shuttling and this may have relevance to pathophysiology of ALS/FTLD. Our antibodies have provided improved detection of C9orf72 protein isoforms, which will help elucidate its physiological function and role in ALS/FTLD.

The loss of Nf1 transiently promotes self-renewal but not tumorigenesis by neural crest stem cells.

Neurofibromatosis is caused by the loss of neurofibromin (Nf1), leading to peripheral nervous system (PNS) tumors, including neurofibromas and malignant peripheral nerve sheath tumors (MPNSTs). A long-standing question has been whether these tumors arise from neural crest stem cells (NCSCs) or differentiated glia. Germline or conditional Nf1 deficiency caused a transient increase in NCSC frequency and self-renewal in most regions of the fetal PNS. However, Nf1-deficient NCSCs did not persist postnatally in regions of the PNS that developed tumors and could not form tumors upon transplantation into adult nerves. Adult P0a-Cre+Nf1(fl/-) mice developed neurofibromas, and Nf1(+/-)Ink4a/Arf(-/-) and Nf1/p53(+/-) mice developed MPNSTs, but NCSCs did not persist postnatally in affected locations in these mice. Tumors appeared to arise from differentiated glia, not NCSCs.

The C9orf72 repeat expansion itself is methylated in ALS and FTLD patients.

The most common cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) is a G4C2-repeat expansion in C9orf72. However, the lower limit for pathological repeats has not been established and expansions with different sizes could have different pathological consequences. One of the implicated disease mechanisms is haploinsufficiency. Previously, we identified expansion-specific hypermethylation at the 5' CpG-island near the G4C2-repeat, but only in a fraction of carriers (up to 36 %). Here, we tested the hypothesis that the G4C2-repeat itself could be the main site of methylation. To evaluate (G4C2)n -methylation, we developed a novel assay, which was validated by an independent methylation-sensitive restriction enzyme assay. Notably, both assays are qualitative but not quantitative. Blood DNA was available for 270 unrelated individuals, including 71 expansion carriers. In addition, we investigated blood DNA from family members of 16 probands, and 38 DNA samples from multiple tissues of 10 expansion carriers. Finally, we tested DNA from different tissues of an ALS patient carrying a somatically unstable 90-repeat. We demonstrated that the G4C2-expansion is generally methylated in unrelated carriers of alleles >50 repeats (97 %), while small (<22 repeats) or intermediate (22-90 repeats) alleles were completely unmethylated. The presence of (G4C2)n -methylation does not separate the C9orf72-phenotypes (ALS vs. ALS/FTLD vs. FTLD), but has the potential to predict large vs. intermediate repeat length. Our results suggest that (G4C2)n -methylation might sometimes spread to the 5'-upstream region, but not vice versa. It is stable over time, since (G4C2)n -methylation was detected in carriers with a wide range of ages (24-74 years). It was identified in both blood and brain tissues for the same individual, implying its potential use as a biomarker. Furthermore, our findings may open up new perspectives for studying disease mechanisms, such as determining whether methylated and unmethylated repeats have the same ability to form a G-quadruplex configuration.

Skull fracture mimicking eosinophilic granuloma.

BACKGROUND: Delayed swelling after skull fractures is an uncommon complication following head trauma in children. Classically, growing skull fractures typically present in patients under 3 years of age with progressive subcutaneous fluid collections, or occasionally with neurologic symptoms. We present the case of a healthy 2-year-old boy with a lytic "punched-out" frontal skull lesion. The child presented 2 months after a minor forehead injury for which no medical attention was sought. METHODS: The skull defect had no associated leptomeningeal cyst or brain herniation. Imaging and presentation were thought to be consistent with eosinophilic granuloma. Histologic findings demonstrated a healing skull fracture. RESULTS: Cranioplasty was performed, and the patient had an uncomplicated postoperative course. CONCLUSIONS: In this report, we describe our experience with this atypical presentation of a healing skull fracture mimicking a typical eosinophilic granuloma.

Pituitary carcinoma with endolymphatic sac metastasis.

Pituitary carcinoma is characterized by the presence of a metastatic lesion(s) in a location non-contiguous with the original pituitary tumor. The mechanism(s) of malignant transformation are not known. A 15 year-old male was diagnosed in 1982 with a pituitary macroadenoma and acromegaly (random GH 67 ng/ml and no suppression by oral glucose). His prolactin was normal between 18 and 23 ng/ml. Transcranial resection in July 1983 was followed by radiation therapy. The tumor was immunopositive for GH and prolactin. The proliferation MIB-1 index was 0-1%. With aqueous Octreotide 100 mcg 4× daily both GH and IGF-1 became normal. The patient was lost to follow-up and was treated by his local physician. In 2001, his IGF-1 level was 1271 ng/ml, and his random GH was 1.8-2.4 ng/ml by ILMA despite progressive increase in the dose of Sandostatin LAR to 140 mg/month in divided doses. Prolactin remained normal or minimally increased between 15 and 25 ng/ml. In 2009 he was diagnosed with the tumor in the location of left endolymphatic sac. Histological examination showed low grade pituitary carcinoma strongly immunopositive for prolactin but negative for GH. MIB-1 antibody labeled 0-5% cells. In 2012 endoscopic resection of the pituitary tumor remnant was attempted. Immunohistochemical stains were strongly immunopositive for both prolactin and GH, similar to his original pituitary tumor. The MIB-1 proliferation index was low from 0 to 1%. To our knowledge this is the first case of pituitary carcinoma in the endolymphatic sac region. The dichotomy between the cell population of the pituitary lesion (GH/prolactin producing) and the metastasis (purely prolactin-producing) may suggest that the metastatic pituitary lesion derived from a clone distinct from the original one.

Novel mutations in the Anoctamin 5 gene (ANO5) associated with limb-girdle muscular dystrophy 2L.

INTRODUCTION: We present a Jordanian man with the typical LGMD 2L phenotype of early, asymmetric quadriceps weakness and subsequent biceps brachii weakness. METHODS: Case report. RESULTS: Muscle biopsies document a progressive dystrophic pattern unrelated to known sarcolemmal defects associated with muscular dystrophy. Genetic testing revealed novel, heterozygote Anoctamin 5 gene mutations. CONCLUSIONS: This case report expands the known mutations resulting in LGMD 2L and supports the assertion that Anoctamin 5 mutations are more prevalent than previously recognized.

Single-nucleus multiomic atlas of frontal cortex in amyotrophic lateral sclerosis with a deep learning-based decoding of alternative polyadenylation mechanisms.

The understanding of how different cell types contribute to amyotrophic lateral sclerosis (ALS) pathogenesis is limited. Here we generated a single-nucleus transcriptomic and epigenomic atlas of the frontal cortex of ALS cases with C9orf72 (C9) hexanucleotide repeat expansions and sporadic ALS (sALS). Our findings reveal shared pathways in C9-ALS and sALS, characterized by synaptic dysfunction in excitatory neurons and a disease-associated state in microglia. The disease subtypes diverge with loss of astrocyte homeostasis in C9-ALS, and a more substantial disturbance of inhibitory neurons in sALS. Leveraging high depth 3'-end sequencing, we found a widespread switch towards distal polyadenylation (PA) site usage across ALS subtypes relative to controls. To explore this differential alternative PA (APA), we developed APA-Net, a deep neural network model that uses transcript sequence and expression levels of RNA-binding proteins (RBPs) to predict cell-type specific APA usage and RBP interactions likely to regulate APA across disease subtypes.

Whole Exome Sequencing Identifies PHF14 Mutations in Neurocytoma and Predicts Responsivity to the PDGFR Inhibitor Sunitinib.

Neurocytomas are rare low-grade brain tumors predominantly affecting young adults, but their cellular origin and molecular pathogenesis is largely unknown. We previously reported a sellar neurocytoma that secreted excess arginine vasopressin causing syndrome of inappropriate anti-diuretic hormone (SIADH). Whole exome sequencing in 21 neurocytoma tumor tissues identified somatic mutations in the plant homeodomain finger protein 14 (PHF14) in 3/21 (14%) tumors. Of these mutations, two were missense mutations and 4 caused splicing site losses, resulting in PHF14 dysfunction. Employing shRNA-mediated knockdown and CRISPR/Cas9-based knockout approaches, we demonstrated that loss of PHF14 increased proliferation and colony formation in five different human, mouse and rat mesenchymal and differentiated cell lines. Additionally, we demonstrated that PHF14 depletion resulted in upregulation of platelet derived growth factor receptor-alpha (PDGFRα) mRNA and protein in neuroblastoma SHSY-5Y cells and led to increased sensitivity to treatment with the PDGFR inhibitor Sunitinib. Furthermore, in a neurocytoma primary culture harboring splicing loss PHF14 mutations, overexpression of wild-type PHF14 and sunitinib treatment inhibited cell proliferation. Nude mice, inoculated with PHF14 knockout SHSY-5Y cells developed earlier and larger tumors than control cell-inoculated mice and Sunitinib administration caused greater tumor suppression in mice harboring PHF-14 knockout than control SHSY-5Y cells. Altogether our studies identified mutations of PHF14 in 14% of neurocytomas, demonstrate it can serve as an alternative pathway for certain cancerous behavior, and suggest a potential role for Sunitinib treatment in some patients with residual/recurrent neurocytoma.

Spontaneous resolution of an infantile hemangioma in a dorsal root ganglion.

Infantile hemangiomas are tumors commonly seen in children. Few authors have reported infantile hemangiomas affecting the CNS, and there are no prior reports detailing spontaneous resolution of a histologically proven juvenile hemangioma within a dorsal root ganglion. The authors report the case of a newborn boy with a large cutaneous hemangioma in the midline of his back. Spinal MR images were obtained to rule out associated spinal cord tethering, and an intradural spinal lesion was unexpectedly discovered. Biopsy revealed an intradural infantile hemangioma within the dorsal root ganglion, and, based on this diagnosis, no resection was performed. Sixteen months following the biopsy, the cutaneous hemangioma had become involuted and the intradural hemangioma had completely resolved. The behavior of the intradural component in this case follows the natural history of many cutaneous infantile hemangiomas.