@article {986, title = {Dual activating FGFR1 mutations in pediatric pilomyxoid astrocytoma.}, journal = {Mol Genet Genomic Med}, volume = {9}, year = {2021}, month = {2021 02}, pages = {e1597}, abstract = {

BACKGROUND: Pilomyxoid astrocytomas are an aggressive subtype of astrocytoma, not graded by WHO, frequently located in hypothalamic/chiasmatic region, affecting diencephalic structures, and characterized by shorter survival and high recurrence rates. Pilomyxoid astrocytoma management remains controversial, with pathologic tissue diagnosis and relief of mass effect being the main goals of surgery while avoiding treatment-related morbidity, including vision loss, panhypopituitarism, and hypothalamic dysfunction. Chemotherapy (typically vincristine and carboplatin) in all pediatric patients and radiation therapy in pediatric patients over 5~years of age are used for treatment.

METHODS: We report clinical presentation, surgical management, and whole exome sequencing results in a pediatric patient with the subtotally resected pilomyxoid astrocytoma.

RESULTS: We identified two somatic activating missense mutations affecting FGFR1, including FGFR1 p.K656E and FGFR1 p.V561M. While the former is a known hotspot mutation that is both activating and transforming, the latter has been described as a gatekeeper mutation imparting resistance to FGFR inhibitors. Interestingly, both mutations were present with similar variant allele frequency within the tumor.

CONCLUSION: Similar variant allele frequencies of FGFR1 p.K656E and FGFR1 p.V561M mutations in our patient{\textquoteright}s tumor suggest that these mutations may have occurred at similar time points. Use of FGFR inhibitors in addition to STAT3 or PI3K/mTOR inhibition may prove a useful strategy in targeting our patient{\textquoteright}s pilomyxoid astrocytoma.

}, issn = {2324-9269}, doi = {10.1002/mgg3.1597}, author = {Fomchenko, Elena I and Reeves, Benjamin C and Sullivan, William and Marks, Asher M and Huttner, Anita and Kahle, Kristopher T and Erson-Omay, E Zeynep} } @article {914, title = {Exome sequencing implicates genetic disruption of prenatal neuro-gliogenesis in sporadic congenital hydrocephalus.}, journal = {Nat Med}, volume = {26}, year = {2020}, month = {2020 11}, pages = {1754-1765}, abstract = {

Congenital hydrocephalus (CH), characterized by enlarged brain ventricles, is considered a disease of excessive cerebrospinal fluid (CSF) accumulation and thereby treated with neurosurgical CSF diversion with high morbidity and failure rates. The poor neurodevelopmental outcomes and persistence of ventriculomegaly in some post-surgical patients highlight our limited knowledge of disease mechanisms. Through whole-exome sequencing of 381 patients (232 trios) with sporadic, neurosurgically treated CH, we found that damaging de novo mutations account for >17\% of cases, with five different genes exhibiting a significant de novo mutation burden. In all, rare, damaging mutations with large effect contributed to ~22\% of sporadic CH cases. Multiple CH genes are key regulators of neural stem cell biology and converge in human transcriptional networks and cell types pertinent for fetal neuro-gliogenesis. These data implicate genetic disruption of early brain development, not impaired CSF dynamics, as the primary pathomechanism of a significant number of patients with sporadic CH.

}, keywords = {Brain, Cerebral Ventricles, Exome, Female, Genetic Predisposition to Disease, Humans, Hydrocephalus, Male, Mutation, Neural Stem Cells, Neurogenesis, Neuroglia, Transcription Factors, Tripartite Motif Proteins, Ubiquitin-Protein Ligases, Whole Exome Sequencing}, issn = {1546-170X}, doi = {10.1038/s41591-020-1090-2}, author = {Jin, Sheng Chih and Dong, Weilai and Kundishora, Adam J and Panchagnula, Shreyas and Moreno-De-Luca, Andres and Furey, Charuta G and Allocco, August A and Walker, Rebecca L and Nelson-Williams, Carol and Smith, Hannah and Dunbar, Ashley and Conine, Sierra and Lu, Qiongshi and Zeng, Xue and Sierant, Michael C and Knight, James R and Sullivan, William and Duy, Phan Q and DeSpenza, Tyrone and Reeves, Benjamin C and Karimy, Jason K and Marlier, Arnaud and Castaldi, Christopher and Tikhonova, Irina R and Li, Boyang and Pe{\~n}a, Helena Perez and Broach, James R and Kabachelor, Edith M and Ssenyonga, Peter and Hehnly, Christine and Ge, Li and Keren, Boris and Timberlake, Andrew T and Goto, June and Mangano, Francesco T and Johnston, James M and Butler, William E and Warf, Benjamin C and Smith, Edward R and Schiff, Steven J and Limbrick, David D and Heuer, Gregory and Jackson, Eric M and Iskandar, Bermans J and Mane, Shrikant and Haider, Shozeb and Guclu, Bulent and Bayri, Yasar and Sahin, Yener and Duncan, Charles C and Apuzzo, Michael L J and DiLuna, Michael L and Hoffman, Ellen J and {\v S}estan, Nenad and Ment, Laura R and Alper, Seth L and Bilguvar, Kaya and Geschwind, Daniel H and G{\"u}nel, Murat and Lifton, Richard P and Kahle, Kristopher T} } @article {925, title = {Exome Sequencing Implicates Impaired GABA Signaling and Neuronal Ion Transport in Trigeminal Neuralgia.}, journal = {iScience}, volume = {23}, year = {2020}, month = {2020 Oct 23}, pages = {101552}, abstract = {

Trigeminal neuralgia (TN) is a common, debilitating neuropathic face pain syndrome often resistant to therapy. The familial clustering of TN cases suggests that genetic factors play a role in disease pathogenesis. However, no unbiased, large-scale genomic study of TN has been performed to date. Analysis of 290 whole exome-sequenced TN probands, including 20 multiplex kindreds and 70 parent-offspring trios, revealed enrichment of rare, damaging variants in GABA receptor-binding genes in cases. Mice engineered with a TN-associated mutation (p.Cys188Trp) in the GABA receptor Cl channel γ-1 subunit () exhibited trigeminal mechanical allodynia and face pain behavior. Other TN probands harbored rare damaging variants in Na and Ca channels, including a significant variant burden in the α-1H subunit of the voltage-gated Ca channel Ca3.2 (). These results provide exome-level insight into TN and implicate genetically encoded impairment of GABA signaling and neuronal ion transport in TN pathogenesis.

}, issn = {2589-0042}, doi = {10.1016/j.isci.2020.101552}, author = {Dong, Weilai and Jin, Sheng Chih and Allocco, August and Zeng, Xue and Sheth, Amar H and Panchagnula, Shreyas and Castonguay, Annie and Lorenzo, Louis-{\'E}tienne and Islam, Barira and Brindle, Genevi{\`e}ve and Bachand, Karine and Hu, Jamie and Sularz, Agata and Gaillard, Jonathan and Choi, Jungmin and Dunbar, Ashley and Nelson-Williams, Carol and Kiziltug, Emre and Furey, Charuta Gavankar and Conine, Sierra and Duy, Phan Q and Kundishora, Adam J and Loring, Erin and Li, Boyang and Lu, Qiongshi and Zhou, Geyu and Liu, Wei and Li, Xinyue and Sierant, Michael C and Mane, Shrikant and Castaldi, Christopher and L{\'o}pez-Gir{\'a}ldez, Francesc and Knight, James R and Sekula, Raymond F and Simard, J Marc and Eskandar, Emad N and Gottschalk, Christopher and Moliterno, Jennifer and G{\"u}nel, Murat and Gerrard, Jason L and Dib-Hajj, Sulayman and Waxman, Stephen G and Barker, Fred G and Alper, Seth L and Chahine, Mohamed and Haider, Shozeb and De Koninck, Yves and Lifton, Richard P and Kahle, Kristopher T} } @article {802, title = {New drugs on the horizon for cerebral edema: what{\textquoteright}s in the clinical development pipeline?}, journal = {Expert Opin Investig Drugs}, volume = {29}, year = {2020}, month = {2020 Oct}, pages = {1099-1105}, abstract = {

INTRODUCTION: Research has advanced our understanding of the molecular and cellular mechanisms of cerebral edema and has propelled the development of novel antiedema therapeutics. Current evidence supports aberrant neuro-glial ion transport as a central mechanism that underlies pathological fluid accumulation after central nervous system injury.

AREAS COVERED: Novel agents in clinical development show potential in altering the natural history and treatment of cerebral edema. Using the PubMed and Google Scholar databases, we review recent advances in our understanding of cerebral edema and describe agents under active investigation, their mechanism, and their application in recent and ongoing clinical trials.

EXPERT OPINION: Pharmacotherapies that target molecular mechanisms underlying the compensatory post-injury response of ion channels and transporters that lead to pathological alteration of osmotic gradients are the most promising therapeutic strategies. Repurposing of drugs such as glyburide that inhibit the aberrant upregulation of ion channels such as SUR1-TRPM4, and novel agents, such as ZT-1a, which reestablish physiological regulation of ion channels such as NKCC1/KCC, could be useful adjuvants to prevent and even reverse fluid accumulation in the brain parenchyma.

}, keywords = {Animals, Brain Edema, Drug Development, Drug Repositioning, Drugs, Investigational, Humans, Molecular Targeted Therapy}, issn = {1744-7658}, doi = {10.1080/13543784.2020.1813715}, author = {Robert, Stephanie M and Reeves, Benjamin C and Alper, Seth L and Zhang, Jinwei and Kahle, Kristopher T} } @article {590, title = {EphrinB2-EphB4-RASA1 Signaling in Human Cerebrovascular Development and Disease.}, journal = {Trends Mol Med}, volume = {25}, year = {2019}, month = {2019 04}, pages = {265-286}, abstract = {

Recent whole exome sequencing studies in humans have provided novel insight into the importance of the ephrinB2-EphB4-RASA1 signaling axis in cerebrovascular development, corroborating and extending previous work in model systems. Here, we aim to review the human cerebrovascular phenotypes associated with ephrinB2-EphB4-RASA1 mutations, including those recently discovered in Vein of Galen malformation: the most common and severe brain arteriovenous malformation in neonates. We will also discuss emerging paradigms of the molecular and cellular pathophysiology of disease-causing ephrinB2-EphB4-RASA1 mutations, including the potential role of somatic mosaicism. These observations have potential diagnostic and therapeutic implications for patients with rare congenital cerebrovascular diseases and their families.

}, issn = {1471-499X}, doi = {10.1016/j.molmed.2019.01.009}, author = {Zeng, Xue and Hunt, Ava and Jin, Sheng Chih and Duran, Daniel and Gaillard, Jonathan and Kahle, Kristopher T} } @article {386, title = {De novo mutations in inhibitors of Wnt, BMP, and Ras/ERK signaling pathways in non-syndromic midline craniosynostosis.}, journal = {Proc Natl Acad Sci U S A}, volume = {114}, year = {2017}, month = {2017 08 29}, pages = {E7341-E7347}, abstract = {

Non-syndromic craniosynostosis (NSC) is a frequent congenital malformation in which one or more cranial sutures fuse prematurely. Mutations causing rare syndromic craniosynostoses in humans and engineered mouse models commonly increase signaling of the Wnt, bone morphogenetic protein (BMP), or Ras/ERK pathways, converging on shared nuclear targets that promote bone formation. In contrast, the genetics of NSC is largely unexplored. More than 95\% of NSC is sporadic, suggesting a role for de novo mutations. Exome sequencing of 291 parent-offspring trios with midline NSC revealed 15 probands with heterozygous damaging de novo mutations in 12 negative regulators of Wnt, BMP, and Ras/ERK signaling (10.9-fold enrichment, = 2.4 {\texttimes} 10). had 4 de novo and 14 transmitted mutations; no other gene had more than 1. Four familial NSC kindreds had mutations in genes previously implicated in syndromic disease. Collectively, these mutations contribute to 10\% of probands. Mutations are predominantly loss-of-function, implicating haploinsufficiency as a frequent mechanism. A common risk variant near increased the penetrance of mutations and was overtransmitted to patients with de novo mutations in other genes in these pathways, supporting a frequent two-locus pathogenesis. These findings implicate new genes in NSC and demonstrate related pathophysiology of common non-syndromic and rare syndromic craniosynostoses. These findings have implications for diagnosis, risk of recurrence, and risk of adverse neurodevelopmental outcomes. Finally, the use of pathways identified in rare syndromic disease to find genes accounting for non-syndromic cases may prove broadly relevant to understanding other congenital disorders featuring high locus heterogeneity.

}, keywords = {Adult, Animals, Bone Morphogenetic Proteins, Child, Child, Preschool, Cranial Sutures, Craniosynostoses, Exome, Female, Humans, Male, MAP Kinase Signaling System, Mutation, Osteogenesis, Penetrance, Phenotype, ras Proteins, Sequence Analysis, DNA, Signal Transduction, Smad6 Protein, Whole Exome Sequencing}, issn = {1091-6490}, doi = {10.1073/pnas.1709255114}, author = {Timberlake, Andrew T and Furey, Charuta G and Choi, Jungmin and Nelson-Williams, Carol and Loring, Erin and Galm, Amy and Kahle, Kristopher T and Steinbacher, Derek M and Larysz, Dawid and Persing, John A and Lifton, Richard P} } @article {407, title = {Digenic mutations of human paralogs in Dent{\textquoteright}s disease type 2 associated with Chiari I malformation.}, journal = {Hum Genome Var}, volume = {3}, year = {2016}, month = {2016}, pages = {16042}, abstract = {

and its paralog encode phosphatidylinositol 5-phosphatases that localize to the primary cilium and have roles in ciliogenesis. Mutations in cause the X-linked Dent disease type 2 (DD2; OMIM$\#$ 300555), characterized by low-molecular weight proteinuria, hypercalciuria, and the variable presence of cataracts, glaucoma and intellectual disability without structural brain anomalies. Disease-causing mutations in have not been described in humans. Here, we report the case of an 11-year-old boy with short stature and an above-average IQ; severe proteinuria, hypercalciuria and osteopenia resulting in a vertebral compression fracture; and Chiari I malformation with cervico-thoracic syringohydromyelia requiring suboccipital decompression. Sequencing revealed a novel, DD2-causing 462 bp deletion disrupting exon 3 of and a maternally inherited, extremely rare (ExAC allele frequency 8.4{\texttimes}10) damaging missense mutation in (p.A51V). This mutation substitutes an evolutionarily conserved amino acid in the protein{\textquoteright}s critical PH domain. analyses of mutation impact predicted by SIFT, PolyPhen2, MetaSVM and CADD algorithms were all highly deleterious. Together, our findings report a novel association of DD2 with Chiari I malformation and syringohydromyelia, and document the effects of digenic mutation of human paralogs. These findings lend genetic support to the hypothesis that impaired ciliogenesis may contribute to the development of Chiari I malformation, and implicates OCRL-dependent PIP metabolism in this mechanism.

}, issn = {2054-345X}, doi = {10.1038/hgv.2016.42}, author = {Duran, Daniel and Jin, Sheng Chih and DeSpenza, Tyrone and Nelson-Williams, Carol and Cogal, Andrea G and Abrash, Elizabeth W and Harris, Peter C and Lieske, John C and Shimshak, Serena Je and Mane, Shrikant and Bilguvar, Kaya and DiLuna, Michael L and G{\"u}nel, Murat and Lifton, Richard P and Kahle, Kristopher T} }