Down-regulation of oxidative phosphorylation in the liver by expression of the ATPase inhibitory factor 1 induces a tumor-promoter metabolic state

The ATPase Inhibitory Factor 1 (IF1) is an inhibitor of the mitochondrial H+-ATP synthase that regulates the activity of both oxidative phosphorylation (OXPHOS) and cell death. Here, we have developed transgenic Tet-On and Tet-Off mice that express a mutant active form of hIF1 in the hepatocytes to restrain OXPHOS in the liver to investigate the relevance of mitochondrial activity in hepatocarcinogenesis. The expression of hIF1 promotes the inhibition of OXPHOS in both Tet-On and Tet- Off mouse models and induces a state of metabolic preconditioning guided by the activation of the stress kinases AMPK and p38 MAPK. Expression of the transgene significantly augmented proliferation and apoptotic resistance of carcinoma cells, which contributed to an enhanced diethylnitrosamine-induced liver carcinogenesis. Moreover, the expression of hIF1 also diminished acetaminophen-induced apoptosis, which is unrelated to differences in permeability transition pore opening. Mechanistically, cell survival in hIF1-preconditioned hepatocytes results from a nuclear factor-erythroid 2-related factor (Nrf2)-guided antioxidant response. The results emphasize in vivo that a metabolic phenotype with a restrained OXPHOS in the liver is prone to the development of cancerMINECO (SAF2013-41945-R to JMC and SAF2012-33243 to AMV), CIBERER-ISCIII to JMC and CIBERDEM-ISCIII to AMV, Comunidad de Madrid (S2011/BMD-2402 to JMC and S2010/BMD-2423 to AMV), Fundación Ramón Areces (FRA)Peer Reviewe

Novel constitutive CNV detected in Wilms Tumor.

<p>Schematic representation of CNVs detected in both blood and tissue by aCGH. Duplications (blue bars): 2p21 including <i>SIX3</i>, 3p22.1 with <i>CTNNB1</i>, 4p16.3 with <i>FGFR3</i>, and 20q13.3 with <i>SALL4</i>. Deletion (red bar): 19q13.31 including <i>ZNF227</i>, <i>ZNF233</i> and <i>ZNF235</i>. All the alterations were also detected in matched tumor samples.</p

Specific variants in WDR35 cause a distinctive form of ellis-van creveld syndrome by disrupting the recruitment of the evc complex and smo into the cilium

© The Author 2015. Published by Oxford University Press. All rights reserved. Most patients with Ellis-van Creveld syndrome (EvC) are identified with pathogenic changes in EVC or EVC2, however further genetic heterogeneity has been suggested. In this report we describe pathogenic splicing variants in WDR35, encoding retrograde intraflagellar transport protein 121 (IFT121), in three families with a clinical diagnosis of EvC but having a distinctive phenotype. To understand why WDR35 variants result in EvC, we analysed EVC, EVC2 and Smoothened (SMO) in IFT-A deficient cells. We found that the three proteins failed to localize to Wdr35 -/- cilia, but not to the cilium of the IFT retrograde motor mutant Dync2h1 -/- , indicating that IFT121 is specifically required for their entry into the ciliary compartment. Furthermore expression of Wdr35 disease cDNAs in Wdr35 -/- fibroblasts revealed that the newly identified variants lead to Hedgehog signalling defects resembling those of Evc -/- and Evc2 -/- mutants. Together our data indicate that splicing variants in WDR35, and possibly in other IFT-A components, underlie a number of EvC cases by disrupting targeting of both the EvC complex and SMO to cilia

CLAPO syndrome: identification of somatic activating PIK3CA mutations and delineation of the natural history and phenotype

[Purpose]: CLAPO syndrome is a rare vascular disorder characterized by capillary malformation of the lower lip, lymphatic malformation predominant on the face and neck, asymmetry, and partial/generalized overgrowth. Here we tested the hypothesis that, although the genetic cause is not known, the tissue distribution of the clinical manifestations in CLAPO seems to follow a pattern of somatic mosaicism.[Methods]: We clinically evaluated a cohort of 13 patients with CLAPO and screened 20 DNA blood/tissue samples from 9 patients using high-throughput, deep sequencing.[Results]: We identified five activating mutations in the PIK3CA gene in affected tissues from 6 of the 9 patients studied; one of the variants (NM_006218.2:c.248T>C; p.Phe83Ser) has not been previously described in developmental disorders.[Conclusion]: We describe for the first time the presence of somatic activating PIK3CA mutations in patients with CLAPO. We also report an update of the phenotype and natural history of the syndrome.This research was supported by the project “Genetics of vascular and lymphatic malformations” financed with funds donated by Asociación Ultrafondo and Villareal FC, cofinanced by project IP-17 from the funding call “Todos Somos Raros” (Telemaraton TVE promoted by Fundación Isabel Gemio, Federación ASEM, and Federación Española de Enfermedades Raras), cofinanced by the Instituto de Salud Carlos III, FEDER FUNDS FIS PI15/01481, and IIS-Fundación Jiménez Díaz UAM Genome Medicine Chair.Peer reviewe

PIAS4 is associated with macro/microcephaly in the novel interstitial 19p13.3 microdeletion/microduplication syndrome

Array comparative genomic hybridization (aCGH) is a powerful genetic tool that has enabled the identification of novel imbalances in individuals with intellectual disability (ID), autistic disorders and congenital malformations. Here we report a \u27genotype first\u27 approach using aCGH on 13 unrelated patients with 19p13.3 submicroscopic rearrangement (11 deletions and 2 duplications) and review cases in the literature and in public databases. Shared phenotypic features suggest that these patients represent an interstitial microdeletion/microduplication syndrome at 19p13.3. Common features consist of abnormal head circumference in most patients (macrocephaly with the deletions and microcephaly with the duplications), ID with developmental delay (DD), hypotonia, speech delay and common dysmorphic features. The phenotype is associated with at least a ~0.113 Mb critical region harboring three strong candidate genes probably associated with DD, ID, speech delay and other dysmorphic features: MAP2K2, ZBTB7A and PIAS4, an E3 ubiquitin ligase involved in the ubiquitin signaling pathways, which we hypothesize for the first time to be associated with head size in humans