De novo complex intra chromosomal rearrangement after ICSI: characterisation by BACs micro array-CGH

<p>Abstract</p> <p>Background</p> <p>In routine Assisted Reproductive Technology (ART) men with severe oligozoospermia or azoospermia should be informed about the risk of de novo congenital or chromosomal abnormalities in ICSI program. Also the benefits of preimplantation or prenatal genetic diagnosis practice need to be explained to the couple.</p> <p>Methods</p> <p>From a routine ICSI attempt, using ejaculated sperm from male with severe oligozoospermia and having normal karyotype, a 30 years old pregnant woman was referred to prenatal diagnosis in the 17^thweek for bichorionic biamniotic twin gestation. Amniocentesis was performed because of the detection of an increased foetal nuchal translucency for one of the fetus by the sonographic examination during the 12^thweek of gestation (WG). Chromosome and DNA studies of the fetus were realized on cultured amniocytes</p> <p>Results</p> <p>Conventional, molecular cytogenetic and microarray CGH experiments allowed us to conclude that the fetus had a <it>de novo </it>pericentromeric inversion associated with a duplication of the 9p22.1-p24 chromosomal region, 46,XY,invdup(9)(p22.1p24) [arrCGH 9p22.1p24 (RP11-130C19 → RP11-87O1)x3]. As containing the critical 9p22 region, our case is in coincidence with the general phenotype features of the partial trisomy 9p syndrome with major growth retardation, microcephaly and microretrognathia.</p> <p>Conclusion</p> <p>This de novo complex chromosome rearrangement illustrates the possible risk of chromosome or gene defects in ICSI program and the contribution of array-CGH for mapping rapidly de novo chromosomal imbalance.</p

Anophthalmia, hearing loss, abnormal pituitary development and response to growth hormone therapy in three children with microdeletions of 14q22q23

BACKGROUND: Microdeletions of 14q22q23 have been associated with eye abnormalities and pituitary defects. Other phenotypic features in deletion carriers including hearing loss and response to growth hormone therapy are less well recognized. We studied genotype and phenotype of three newly identified children with 14q22q23 deletions, two girls and one boy with bilateral anophthalmia, and compared them with previously published deletion patients and individuals with intragenic defects in genes residing in the region. RESULTS: The three deletions were de novo and ranged in size between 5.8 and 8.9 Mb. All three children lacked one copy of the OTX2 gene and in one of them the deletion involved also the BMP4 gene. All three patients presented partial conductive hearing loss which tended to improve with age. Analysis of endocrine and growth phenotypes showed undetectable anterior pituitary, growth hormone deficiency and progressive growth retardation in all three patients. Growth hormone therapy led to partial catch-up growth in two of the three patients but just prevented further height loss in the third. CONCLUSIONS: The pituitary hypoplasia, growth hormone deficiency and growth retardation associated with 14q22q23 microdeletions are very remarkable, and the latter appears to have an atypical response to growth hormone therapy in some of the cases

Modeling the influence of stromal microenvironment in the selection of ENU-induced BCR-ABL1 mutants by tyrosine kinase inhibitors

International audienceTyrosine kinase inhibitors (TKIs) have profoundly changed the natural history of chronic myeloid leukemia (CML). However, acquired resistance to imatinib, dasatinib or nilotinib (1(st) and 2(nd) generation TKIs), due in part to BCR-ABL1 kinase mutations, has been largely described. These drugs are ineffective on the T315I gatekeeper substitution, which remains sensitive to 3(rd) generation TKI ponatinib. It has recently been suggested that the hematopoietic niche could protect leukemic cells from targeted therapy. In order to investigate the role of a stromal niche in mutation-related resistance, we developed a niche-based cell mutagenesis assay. For this purpose, ENU (N-ethyl-N-nitrosourea)-exposed UT-7 cells expressing non-mutated or T315I-mutated BCR-ABL1 were cultured with or without murine MS-5 stromal cells and in the presence of imatinib, dasatinib, nilotinib, or ponatinib. In the assays relative to 1(st) and 2(nd) generation TKIs, which were performed on non-mutated BCR-ABL1 cells, our data highlighted the increasing efficacy of the latter, but did not reveal any substantial effect of the niche. In ponatinib assays performed on both non-mutated and T315I-mutated BCR-ABL1 cells, an increased number of resistant clones were observed in the presence of MS-5. Present data suggested that T315I mutants need either compound mutations (e.g. E255K/T315I) or a stromal niche to escape from ponatinib. Using array-comparative genomic hybridization experiments, we found an increased number of variations (involving some recurrent chromosome regions) in clones cultured on MS-5 feeder. Overall, our study suggests that the hematopoietic niche could play a crucial role in conferring resistance to ponatinib, by providing survival signals and favoring genetic instability

Superoxide dismutase 2 (SOD2) contributes to genetic stability of native and T315I-mutated BCR-ABL expressing leukemic cells

International audienceManganese Superoxide dismutase 2 (SOD2) plays a crucial role in antioxidant defense but there are no data suggesting its role in genetic instability in CML. We evaluated the effects of SOD2 silencing in human UT7 cell line expressing either non-mutated or T315I-mutated BCR-ABL. Array-CGH experiments detected in BCR-ABL-expressing cells silenced for SOD2 a major genetic instability within several chromosomal loci, especially in regions carrying the glypican family (duplicated) and β-defensin genes (deleted). In a large cohort of patients with chronic myeloid leukemia (CML), a significant decrease of SOD2 mRNA was observed. This reduction appeared inversely correlated with leukocytosis and Sokal score, high-risk patients showing lower SOD2 levels. The analysis of anti-oxidant gene expression analysis revealed a specific down-regulation of the expression of PRDX2 in UT7-BCR-ABL and UT7-T315I cells silenced for SOD2 expression. Gene set enrichment analysis performed between the two SOD2-dependent classes of CML patients revealed a significant enrichment of Reactive Oxygen Species (ROS) Pathway. Our data provide the first evidence for a link between SOD2 expression and genetic instability in CML. Consequently, SOD2 mRNA levels should be analyzed in prospective studies as patients with low SOD2 expression could be more prone to develop a mutator phenotype under TKI therapies

Towards a clinical use of human embryonic stem cell-derived cardiac progenitors: a translational experience

International audienceAim This paper describes the multi-step translational approach that has resulted in the generation of clinical-grade human embryonic stem cell-derived cardiac progenitor cells for transplantation in patients with severe ischaemic heart failure. There is now compelling evidence that cells committed to a cardiac lineage are most effective for improving the function of infarcted hearts. This has been confirmed by our pre-clinical studies entailing transplantation of human embryonic stem cell (hESC)-derived cardiac progenitors in rat and non-human primate models of myocardial infarction. These data have paved the way for a translational programme aimed at a phase I clinical trial. Methods and results The main steps of this programme have included (i) the expansion of a clone of pluripotent hESC to generate a master cell bank under good manufacturing practice conditions (GMP); (ii) a growth factor-induced cardiac specification; (iii) the purification of committed cells by immunomagnetic sorting to yield a stage-specific embryonic antigen (SSEA)-1-positive cell population strongly expressing the early cardiac transcription factor Isl-1; (iv) the incorporation of these cells into a fibrin scaffold; (v) a safety assessment focused on the loss of teratoma-forming cells by in vitro (transcriptomics) and in vivo (cell injections in immunodeficient mice) measurements; (vi) an extensive cytogenetic and viral testing; and (vii) the characterization of the final cell product and its release criteria. The data collected throughout this process have led to approval by the French regulatory authorities for a first-in-man clinical trial of transplantation of these SSEA-1(+) progenitors in patients with severely impaired cardiac function. Conclusion Although several facets of this manufacturing process still need to be improved, these data may yet provide a useful platform for the production of hESC-derived cardiac progenitor cells under safe and cost-effective GMP conditions

Superoxide dismutase 2 (SOD2) contributes to genetic stability of native and T315I-mutated BCR-ABL expressing leukemic cells

International audienceManganese Superoxide dismutase 2 (SOD2) plays a crucial role in antioxidant defense but there are no data suggesting its role in genetic instability in CML. We evaluated the effects of SOD2 silencing in human UT7 cell line expressing either non-mutated or T315I-mutated BCR-ABL. Array-CGH experiments detected in BCR-ABL-expressing cells silenced for SOD2 a major genetic instability within several chromosomal loci, especially in regions carrying the glypican family (duplicated) and β-defensin genes (deleted). In a large cohort of patients with chronic myeloid leukemia (CML), a significant decrease of SOD2 mRNA was observed. This reduction appeared inversely correlated with leukocytosis and Sokal score, high-risk patients showing lower SOD2 levels. The analysis of anti-oxidant gene expression analysis revealed a specific down-regulation of the expression of PRDX2 in UT7-BCR-ABL and UT7-T315I cells silenced for SOD2 expression. Gene set enrichment analysis performed between the two SOD2-dependent classes of CML patients revealed a significant enrichment of Reactive Oxygen Species (ROS) Pathway. Our data provide the first evidence for a link between SOD2 expression and genetic instability in CML. Consequently, SOD2 mRNA levels should be analyzed in prospective studies as patients with low SOD2 expression could be more prone to develop a mutator phenotype under TKI therapies

OR04-4 Loss of KDM1A in Bilateral Macronodular Adrenal Hyperplasia With GIP-Dependent Cushing's Syndrome and in Acromegaly With Paradoxical GH Response to Oral Glucose

CONTEXT : Primary bilateral macronodular adrenal hyperplasia (PBMAH) with glucose-dependent insulinotropic polypeptide (GIP)-dependent Cushing's syndrome is caused by ectopic expression of GIP receptor (GIPR) in the adrenal lesions. Such ectopic expression of GIPR was also reported in other endocrine neoplasm, notably in somatotroph pituitary adenomas from acromegalic patients with paradoxical increase of GH after oral glucose load, suggesting a common molecular pathogenesis. We aimed to identify the driver event responsible for GIP-dependent PBMAH with Cushing's syndrome and ectopic GIPR expression in somatotropinomas. [...