De novo Unbalanced 1;22 Translocation with 22q11 Deletion Syndrome.

This report describes a newborn girl presenting with some of the common features of DiGeorge syndrome/velocardiofacial syndrome (DGS/VCFS), including hypocalcemia, atrial septal defect, and aortic stenosis. Several genetic tests were carried out to determine the origin of the clinical phenotype. MLPA was initially performed followed by aCGH, cytogenetic analysis, and FISH. Cytogenetic analysis of the proband's parents was also done. MLPA revealed a deletion in 22q11.1q11.2 spanning from the cat eye syndrome region to the most commonly deleted region in DGS/VCFS patients. The size of the deletion as defined by aCGH was 3.2 Mb. The karyotype of the proband was 45,XX,der(1)t(1;22)(p36.3;q11.2)dn,-22, the karyotypes of the parents were normal. FISH analysis showed that the 22q11 deletion occurred in the der(1). No loss or gain of chromosomal material was evident for chromosome 1, as confirmed by MLPA, aCGH, and FISH. Unbalanced translocations resulting in DGS are relatively rare, with limited reports in the literature. To our knowledge, this is the second case involving chromosome 1 and the first one with breakpoints in 1p36 and 22q11.2. This case also emphasizes the importance of combining diagnostic methods to better understand a given genetic abnormality.

An uncommon case of chronic myeloid leukemia with variant cytogenetic.

Chronic Myeloid Leukemia (CML) is myeloproliferative neoplasm characterized by Philadelphia chromosome which is a balanced translocation between chromosome 9 and 22 in 90% of cases. However, variant cytogenetic still happens in 5-10 % of cases, the importance of which is controversial as well as its response to therapy, prognosis and progression to acute leukemias. Here we report a male patient with CML and variant cytogenetic who responded to low dose of Dasatinib (50 mg daily).

[Di George syndrome: not always a pediatric diagnosis]. / Sindrome di Di George: una diagnosi non sempre pediatrica.

We describe a delayed diagnosis of Di George syndrome, in a 51 yr-old woman, with past medical history of epilepsy, mental retardation, chronic psychosis, nephrocalcinosis. She presented facial dysmorphism, multiple encephalic calcifications, hypocalcemia and lymphopenia. A microdeletion of 22q 11.2 was detected by fluorescence in situ hybridization (FISH), confirming the clinical suspicion .

22q11.2 deletion presenting with severe hypocalcaemia, seizure and basal ganglia calcification in an adult man.

We report a 40-year-old man who was found to have profound hypocalcaemia and hypoparathyroidism when investigated for multiple, generalized, tonic/clonic seizures and a chest infection. Computed tomography scan of the brain revealed extensive symmetric bilateral calcification within the cerebellum, thalamus and basal ganglia. Molecular cytogenetic testing by fluorescent in situ hybridization using the commercial Vysis LSI DiGeorge/VCFS dual colour probe set showed a deletion of 22q11.2. The extraordinary feature of this case is the adult presentation of hypocalcaemia, hypoparathyroidism and basal ganglia calcification due to 22q11.2 deletion.

Centromere activity in dicentric small supernumerary marker chromosomes.

Twenty-five dicentric small supernumerary marker chromosomes (sSMC) derived from #13/21, #14, #15, #18, and #22 were studied by immunohistochemistry for their centromeric activity. Centromere protein (CENP)-B was applied as marker for all centromeres and CENP-C to label the active ones. Three different 'predominant' activation patterns could be observed, i.e., centric fusion or either only one or all two centromeres were active. In one inherited case, the same activation pattern was found in mother and son. In acrocentric-derived sSMC, all three activation patterns could be present. In contrary, in chromosome 18-derived sSMC, only the fusion type was observed. In concordance with previous studies a certain centromeric plasticity was observed in up to 13% of the cells of an individual case. Surprisingly, the obtained data suggests a possible influence of the sSMC carrier's gender on the implementation of the predominant activation pattern; especially, only one active centromere was found more frequently in female than in male carriers. Also, it might be suggested that dicentric sSMC with one active centromere could be less stable than such with two active ones-centromeric plasticity might have an influence here, as well. Also, centromere activity in acrocentric-derived dicentrics could be influenced by heteromorphisms of the corresponding short arms. Finally, evidence is provided that the closer the centromeres of a dicentric are and if they are not fused, the more likely it was that both of them became active. In concordance and refinement with previous studies, a distance of 1.4 Mb up to about 13 Mb the two active centromere state was favored, while centromeric distance of over approximately 15 Mb lead to inactivation of one centromere. Overall, here, the first and largest ever undertaken study in dicentric sSMC is presented, providing evidence that the centromeric activation pattern is, and parental origin may be of interest for their biology. Influence of mechanisms similar or identical to meiotic imprinting in the centromeric regions of human chromosomes might be present. Furthermore, centromeric activation pattern could be at least in parts meaningful for the clinical outcome of dicentric sSMC, as sSMC stability and mosaicism can make the difference between clinically normal and abnormal phenotypes.

Low thymic output in the 22q11.2 deletion syndrome measured by CCR9+CD45RA+ T cell counts and T cell receptor rearrangement excision circles.

Thymic hypoplasia is a frequent feature of the 22q11.2 deletion syndrome, but we know little about patients' age-related thymic output and long-term consequences for their immune system. We measured the expression of T cell receptor rearrangement excision circles (TREC) and used flow cytometry for direct subtyping of recent thymic emigrant (RTE)-related T cells in 43 patients (aged 1-54 years; median 9 years) from all over Norway and in age-matched healthy controls. Thymic volumes were estimated by ultrasound in patients. TREC levels correlated well with RTE-related T cells defined by co-expression of CD3, CD45RA and CCR9 (r=0.84) as well as with the CD4+ and CD8+ T cell subtypes. RTE-related T cell counts also paralleled age-related TREC reductions. CD45RA+ T cells correlated well with absolute counts of CD4+ (r=0.87) and CD8+ (r=0.75) RTE-related T cells. Apart from CD45RA- T cells, all T cell subsets were lower in patients than in controls. Thymic volumes correlated better with RTE-related cells (r=0.46) than with TREC levels (r=0.38). RTE-related T cells and TREC levels also correlated well (r=0.88) in patients without an identifiable thymus. Production of RTEs is impaired in patients with a 22q11.2 deletion, and CCR9 appears to be a good marker for RTE-related T cells.

Automatic analysis of local nasal features in 22q11.2DS affected individuals.

The 22q11.2 deletion syndrome is a common genetic condition with an estimated prevalence between 1:2000 and 1:6000 live births in the US. The syndrome is manifested in multiple different craniofacial features. The nasal area is known to play a role in assessing the extent of dysmorphology of an individual patient. In this paper, we present a method for detecting and assessing the severity of a common nasal feature: the bulbous nasal tip. Our method locates the nose and computes four descriptors, each of which leads to a severity score. Experiments with the four severity scores and a combinations of the best two show that using all five scores gives the best prediction of bulbous nasal tip. Furthermore, the bulbous nasal tip measures outperformed the median of human experts and attains similar results to our own prior work on global descriptors [12] for prediction of 22q11.2DS.

Desmoplastic small round cell tumor in children: a new therapeutic approach.

PURPOSE: Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive malignancy with distinctive histologic and immunohistochemical features occurring in a young population with a male predominance. The tumor appears to arise as masses in the abdominal cavity without a clear visceral origin. Five patients with DSRCT were treated as usual with combined chemoradiation and surgery. In addition, in our center, patients underwent autologous bone marrow transplant (BMT), which is a novel approach to this disease. METHODS: Charts of 5 patients (4 males, mean age of 11 years) treated between 2000 and 2007 were reviewed. The diagnosis of DSRCT was made on the basis of clinical examination, computed tomographic scan, and explorative laparotomy with biopsy, and biochemical markers were negative. All patients were treated with aggressive chemoradiation and surgery. Three patients also had autologous BMT. RESULTS: Three patients (BMT recipients) responded to treatment. The responding patients had surgery with the intent of removing all disease. Two patients died of their cancer, neither of whom underwent BMT. CONCLUSION: The patients DSRCT are sensitive to an aggressive combination of chemotherapy, surgical debulking, and radiation therapy, followed by autologous BMT. It appears that this new multifaceted treatment offers good palliation, which may prolong survival and a possible cure.

Chronic neutrophilic leukemia with congenital Robertsonian translocation successfully treated with allogeneic bone marrow transplantation in a young man.

We present a 23-year-old man with chronic neutrophilic leukemia (CNL). Physical examination revealed hepatosplenomegaly. Leukocytosis was evident with predominance of mature neutrophils with basophilic granules. Bone marrow aspiration revealed mature myeloid hyperplasia. Congenital Robertsonian translocation [45,XY,der(13;22)(q10;q10), in all of analyzed 20 cells] was detected; however, cytogenetic and molecular studies for 9:22 translocation were negative. He was diagnosed with CNL and hydroxyurea was started to control his symptoms and white blood cell count. He was then successfully treated with allogeneic bone marrow transplantation (BMT). Although the prognosis of CNL was not determined, curative therapy including allogeneic hematopoietic stem cell transplantation should be attempted in young patients with CNL.

t(3;9;22) 3-way chromosome translocation in chronic myeloid leukemia is associated with poor prognosis.

Chronic myelogenous leukemia (CML) is genetically characterized by the reciprocal translocation of chromosome 9 and 22. Around 5-8% of CML develop complex variant Ph translocations involving one or more chromosomal regions besides 9 and 22. Chromosome 3 is not frequently involved in complex translocations in CML. We report in this study a case of CML displaying a t(3;9;22) 3-way translocation. A review of the literature appears to indicate that CML patients with this translocation tend to have an aggressive course and poor outcome. Additional 3-way chromosome translocations associated with CML are also reviewed.

[Case report of a subcutaneous peripheral primitive neuroectodermal tumor]. / Tumor subcutáneo neuroectodérmico primitivo periférico. A propósito de un caso.

Peripheral primitive neuroectodermal tumors - also known as Ewing sarcomas - are a rare type of malignant tumor the histology of which characteristically reveals the presence of small round cells. Typically, t(11;22) translocation is observed. We describe the case of a 45-year-old man with a subcutaneous peripheral primitive neuroectodermal tumor in which the t(11;22) translocation was detected. He was satisfactorily treated with surgery and radiotherapy.

[Dermatofibrosarcoma protuberans]. / Dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans (DFSP) is a soft tissue neoplasm of intermediate malignancy that is initially localized to the skin from where it can invade deep structures (fat, fascia, muscle and bone). It is the most frequent fibrohistiocytic tumor, comprising approximately 1.8 % of all soft tissue sarcomas and 0.1 % of all cancers. It has an estimated incidence of 0.8-5 cases per one million persons per year. Treatment of localized disease consists in complete surgical excision of the lesion by conventional surgery with wide margins (>3 cm) or by micrographic Mohs surgery. Although the cases of metastatic DFSP do not reach 5 % of the total, almost all of them appear after previous local relapses. The prognosis for metastatic cases is very poor with a survival of less than 2 years following detection of metastatic disease. Patients with locally advanced DFSP are not candidates for an initial radical surgical therapy therefore neoadyuvant treatment is required prior to surgery in order to reduce tumor burden. In this regard, chemotherapy and radiotherapy have not been highly efficacious so it is necessary to consider new alternatives. The demonstration of the oncogenic power of the translocation COL1A1-PDGFB in DFSP has allowed the successful introduction of drug therapy with antagonists of the PDGFB receptor for metastatic or locally advanced cases.

Distinct patterns of histone methylation and acetylation in human interphase nuclei.

To study 3D nuclear distributions of epigenetic histone modifications such as H3(K9) acetylation, H3(K4) dimethylation, H3(K9) dimethylation, and H3(K27) trimethylation, and of histone methyltransferase Suv39H1, we used advanced image analysis methods, combined with Nipkow disk confocal microscopy. Total fluorescence intensity and distributions of fluorescently labelled proteins were analyzed in formaldehyde-fixed interphase nuclei. Our data showed reduced fluorescent signals of H3(K9) acetylation and H3(K4) dimethylation (di-me) at the nuclear periphery, while di-meH3(K9) was also abundant in chromatin regions closely associated with the nuclear envelope. Little overlapping (intermingling) was observed for di-meH3(K4) and H3(K27) trimethylation (tri-me), and for di-meH3(K9) and Suv39H1. The histone modifications studied were absent in the nucleolar compartment with the exception of H3(K9) dimethylation that was closely associated with perinucleolar regions which are formed by centromeres of acrocentric chromosomes. Using immunocytochemistry, no di-meH3(K4) but only dense di-meH3(K9) was found for the human acrocentric chromosomes 14 and 22. The active X chromosome was observed to be partially acetylated, while the inactive X was more condensed, located in a very peripheral part of the interphase nuclei, and lacked H3(K9) acetylation. Our results confirmed specific interphase patterns of histone modifications within the interphase nuclei as well as within their chromosome territories.

Interleukin-2 receptor beta chain locus rearrangement in a T-cell acute lymphoblastic leukemia.

A translocation t(1;22)(p13;q13) was detected in a child with T-cell acute lymphoblastic leukemia (T-ALL). FISH studies showed that the breakpoint was located in the 5' part of the interleukin-2 receptor beta chain (IL2RB) locus, but could only be located distal to 1p13.3 on the partner chromosome. This is the first case of the IL2RB locus rearrangement in T-ALL. The localization of the breakpoint suggests that the chromosomal translocation results in deregulation of IL2RB expression.

Molecular cytogenetic characterization of deletions on der(9) in chronic myelocytic leukemia.

The t(9;22)(q34;q11), generating the Philadelphia chromosome, is found in more than 90% of patients with chronic myelocytic leukemia (CML). Deletions adjacent to the translocation breakpoint on the derivative chromosome 9 have been described by several groups. These studies revealed two primary points: (1) genomic microdeletions were concomitant with the t(9;22) rearrangement; and (2) the location of the deleted sequence was centromeric to ABL and telomeric to BCR genes. We report on a detailed molecular cytogenetic characterization of chromosomal rearrangements in two CML patients bearing a complex variant t(9;22) and insertions of chromosome 22 sequences in 9q34. Our study shows that the location of the deleted sequences was downstream of the ABL gene and that genomic microdeletions were concomitant with the ins(9;22)(q34;q11q11) rearrangement.

Spinal epidural extraskeletal Ewing sarcoma in an adolescent boy: a case report.

Extraskeletal Ewing sarcoma (EES) represents a rare soft tissue malignant neoplasm histologically similar to skeletal Ewing sarcoma. It occurs mainly in adolescents and young adults and commonly affects the paravertebral regions. The differential diagnosis includes other small, blue round cells tumors. The authors report a case of an EES involving the spinal epidural and paravertebral spaces in an adolescent boy. EES diagnosis was confirmed by features of histologic analysis and immunohistochemistry and by the presence of the t(11;22)(q24;q12) chromosomal translocation by reverse transcriptase-polymerase chain reaction.