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The 22q11.2 region is highly susceptible to genomic rearrangements leading to multiple genomic disorders, including 22q11.2 microdeletion syndrome (22q11.2 DS) (MIM# 188400), 22q11.2 microduplication syndrome (MIM# 608363), supernumerary der(22)t(11;22) syndrome (also known as Emanuel Syndrome; MIM# 609029), and Cat Eye Syndrome (MIM# 115470). In this study, we present data on causes of mortality, average age of death, and the existing associated risk factors in patients with 22q11.2 rearrangements. Our cohort included 223 patients (120 males and 103 females) with confirmed diagnoses of 22q11.2 rearrangements diagnosed through molecular techniques (FISH, MLPA, and CMA). Relatives from patients who have been molecularly confirmed with 22q11.2 rearrangements have also been added to the study, regardless of the presence or absence of symptoms. Of these 223 individuals, 21 (9.4%) died. Deceased patients' rearrangements include 19 microdeletions, 1 microduplication, and 1 patient with a marker chromosome. The median age of death was 3 months and 18 days (ranging from 3 days to 34 years). There were 17 patients who died at pediatric age (80.95%), 3 died at adult age (14.28%), and for 1 of whom, the age of death is unknown (4.76%). Eighteen patients were White Mediterranean (European non-Finnish) (85.71%) whereas three were Amerindian (South American) (14.28%). Mortality from cardiac causes accounted for 71.42%. The second most frequent cause of death was sepsis in two patients (9.52%). One patient died from respiratory failure (4.76%) and one from renal failure (4.76%). Information regarding the cause of death was not available in two patients (9.52%). Most patients who died were diagnosed within the first week of life, the majority on the first day. This study adds additional information on mortality in one of the largest cohorts of patients with 22q11.2 rearrangements in more than 30 years of follow-up.

Phelan-McDermid syndrome (PMS, OMIM# 606232) results from either different rearrangements at the distal region of the long arm of chromosome 22 (22q13.3) or pathogenic sequence variants in the SHANK3 gene. SHANK3 codes for a structural protein that plays a central role in the formation of the postsynaptic terminals and the maintenance of synaptic structures. Clinically, patients with PMS often present with global developmental delay, absent or severely delayed speech, neonatal hypotonia, minor dysmorphic features, and autism spectrum disorders (ASD), among other findings. Here, we describe a cohort of 210 patients with genetically confirmed PMS. We observed multiple variant types, including a significant number of small deletions (<0.5 Mb, 64/189) and SHANK3 sequence variants (21 cases). We also detected multiple types of rearrangements among microdeletion cases, including a significant number with post-zygotic mosaicism (9.0%, 17/189), ring chromosome 22 (10.6%, 20/189), unbalanced translocations ( de novo or inherited, 6.4%), and additional rearrangements at 22q13 (6.3%, 12/189) as well as other copy number variations in other chromosomes, unrelated to 22q deletions (14.8%, 28/189). We compared the clinical and genetic characteristics among patients with different sizes of deletions and with SHANK3 variants . Our findings suggest that SHANK3 plays an important role in this syndrome but is probably not uniquely responsible for all the spectrum features in PMS. We emphasize that only an adequate combination of different molecular and cytogenetic approaches allows an accurate genetic diagnosis in PMS patients. Thus, a diagnostic algorithm is proposed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Nevado, García-Miñaúr, Palomares-Bralo, Vallespín, Guillén-Navarro, Rosell, Bel-Fenellós, Mori, Milá, Campo, Barrúz, Santos-Simarro, Obregón, Orellana, Pachajoa, Tenorio, Galán, Cigudosa, Moresco, Saleme, Castillo, Gabau, Pérez-Jurado, Barcia, Martín, Mansilla, Vallcorba, García-Murillo, Cammarata-Scalisi, Gonçalves Pereira, Blanco-Lago, Serrano, Ortigoza-Escobar, Gener, Seidel, Tirado, Lapunzina and Spanish PMS Working Group.)

Objective: Prenatal diagnoses of microdeletion syndromes without ultrasound findings in the first and second trimester are always difficult. The objective of this study is to report the prenatal ultrasound findings in four foetuses diagnosed with 17q21.31 microdeletions (Koolen-de Vries syndrome) using chromosomal microarrays (CMA)., Patients and Methods: We present four foetuses with 17q21.31 microdeletion. All showed CNS anomalies in the third trimester, three had ventriculomegaly, and one hypogenesis of corpus callosum at 31 weeks of pregnancy., Results: Array-SNPs and CGH-array were performed on uncultured amniocytes and peripheral blood revealing a 17q21.31 microdeletion., Conclusions: Prenatal CNS anomalies (mainly ventriculomegaly) at third trimester, in spite of isolate, should be considered a prenatal ultrasound marker of this syndrome. This kind of malformations raise the possibility of an underlying genetic conditions including 17q21.31 microdeletion; thus, CMA should be taken into consideration when offering prenatal genetic counselling., (© 2021 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals LLC.)

Purpose: NKG2D ligands (NKG2DL) are expressed on various tumor types and immunosuppressive cells within tumor microenvironments, providing suitable targets for cancer therapy. Various immune cells express NKG2D receptors, including natural killer (NK) cells and CD8 + T cells. Interactions between NKG2DL and NKG2D receptors are essential for NK-cell elimination of osteosarcoma tumor-initiating cells. In this report, we used NKG2D-NKG2DL interactions to optimize an immunotherapeutic strategy against osteosarcoma. We evaluated in vitro and in vivo the safety and cytotoxic capacity against osteosarcoma cells of CD45RA - memory T cells expressing an NKG2D-4-1BB-CD3z chimeric antigen receptor (CAR). Experimental Design: CD45RA - cells from healthy donors were transduced with NKG2D CARs containing 4-1BB and CD3z signaling domains. NKG2D CAR expression was analyzed by flow cytometry. In vitro cytotoxicity of NKG2D-CAR + CD45RA - T cells against osteosarcoma was evaluated by performing conventional 4-hour europium-TDA release assays. For the in vivo orthotopic model, 531MII YFP-luc osteosarcoma cells were used as targets in NOD-scid IL2Rg null mice. Results: Lentiviral transduction of NKG2D-4-1BB-CD3z markedly increased NKG2D surface expression in CD45RA - cells. Genetic stability was preserved in transduced cells. In vitro , NKG2D-CAR + memory T cells showed significantly increased cytolytic activity than untransduced cells against osteosarcoma cell lines, while preserving the integrity of healthy cells. NKG2D-CAR + memory T cells had considerable antitumor activity in a mouse model of osteosarcoma, whereas untransduced T cells were ineffective. Conclusions: Our results demonstrate NKG2D-4-1BB-CD3z CAR-redirected memory T cells target NKG2DL-expressing osteosarcoma cells in vivo and in vitro and could be a promising immunotherapeutic approach for patients with osteosarcoma. Clin Cancer Res; 23(19); 5824-35. ©2017 AACR ., (©2017 American Association for Cancer Research.)

Chromosomal abnormalities are detected in 40-60% of patients with de novo myelodysplastic syndromes (MDS). This study used the FISH technique in 773 patients with de novo MDS without evidence of monosomy 7 (-7) or 7q deletion (7q-) by conventional G-banding cytogenetics (CC) to analyze their prognostic impact by FISH alone. FISH detected -7/7q- in 5.2% of patients. Presence of -7/7q- was associated with shorter overall survival than absence of such aberrations. Our results suggest that FISH 7q could be beneficial in patients with intermediate WHO morphologic risk stratification and no evidence of -7/7q- by CC., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

In two patients with hematological neoplasias a tandem repetition of chromosome 21 in the bone marrow was revealed by cytogenetic analysis. The disease was different in the two patients: one was of the lymphoid type, acute lymphoblastic leukemia type L1, and the other was of the myeloid type, acute nonlymphoblastic leukemia type M2. In one case this chromosomal abnormality resulted in amplification of the AML1 gene (HUGO nomenclature: RUNX1), whereas in the other case the AML1 gene was not included in the tandem repetition, showing that apparently similar cytogenetic aberrations may be different at the molecular level.

The evaluation of an automated system for Fluorescence In Situ Hybridization (FISH) spot counting in interphase nuclei is presented in this paper. Different types of experiments have been performed with samples from known populations. In all of them the goal is to detect mosaicism of chromosome X in leukocytes from mixtures in known proportions of healthy male and female blood. First the initial results from the automatic FISH analysis system were obtained and evaluated. Then the analysis was modified to reduce systematic errors, so that the results are closer to what an experienced human operator would have obtained (system calibration step). Finally, an additional control probe of chromosome Y was used to detect and discard cells where incorrect hybridization or other abnormal situations had occurred. In each step the system sensitivity was determined by the use of two statistical validation tests, so that the improvement brought about by the correction methods could be assessed. The results obtained in the study showed that, using both corrections, the system is able to detect 10% monosomies with a significance level alpha = 0.1%.

Cluster division is a critical issue in fluorescence microscopy-based analytical cytology when preparation protocols do not provide appropriate separation of objects. Overlooking clustered nuclei and analyzing only isolated nuclei may dramatically increase analysis time or affect the statistical validation of the results. Automatic segmentation of clustered nuclei requires the implementation of specific image segmentation tools. Most algorithms are inspired by one of the two following strategies: 1) cluster division by the detection of internuclei gradients; or 2) division by definition of domains of influence (geometrical approach). Both strategies lead to completely different implementations, and usually algorithms based on a single view strategy fail to correctly segment most clustered nuclei, or perform well just for a specific type of sample. An algorithm based on morphological watersheds has been implemented and tested on the segmentation of microscopic nuclei clusters. This algorithm provides a tool that can be used for the implementation of both gradient- and domain-based algorithms, and, more importantly, for the implementation of mixed (gradient- and shape-based) algorithms. Using this algorithm, almost 90% of the test clusters were correctly segmented in peripheral blood and bone marrow preparations. The algorithm was valid for both types of samples, using the appropriate markers and transformations.

We exposed human peripheral lymphocytes in vitro to 0.3 and 1 Gy of 60Co gamma rays to evaluate whether the ability and sensitivity to detect chromosomal aberrations by chromosome painting is independent or not to the specific paint probes. To detect structural aberrations (translocations), we painted chromosome spreads simultaneously with two whole-chromosome libraries for chromosomes 1, 2, 3, 4, 5, 6, 7, 11, 13, 16, and 18. To compare the rate of chromosome translocations detected by the different pairs of chromosomes, data were normalized according to the fraction of genome painted and evaluated by unconditional logistic regression. Our results show that any combination of paint probes can be used to score induced chromosomal aberrations. We observed that the amounts of translocations are dose dependent and quite homogeneous within each dose of radiation, independently of chromosomes painted. However, the use of small chromosome probes is not recommended because of the high number of cells to be analyzed due to the small amount of genome painted and because it is more difficult to detect translocations in small chromosomes.

The origin of a de novo metacentric small marker chromosome found in a cytogenetic study in amniotic fluid was determined by fluorescence in situ hybridization (FISH) using chromosome specific probes. It was identified as an isochromosome 18p. We want to emphasize that when an extra chromosome is found in prenatal diagnosis and it cannot be identified by conventional cytogenetics banding, FISH should be applied in order to give real risks for fetal anomalies and an accurate genetic counselling.