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Bastida-Lertxundi N.,University Hospital Alava | Lopez-Lopez E.,University of the Basque Country | Pinan M.A.,University Hospital Cruces | Puiggros A.,Laboratori Of Citogenetica Molecular | And 4 more authors.
Cancer Genetics | Year: 2014

The identification of new cryptic deletions and duplications can be used to improve prognostic classification in cancer. To obtain accurate results, it is necessary to discriminate between somatic alterations in the tumor cell and germline polymorphisms. For this purpose, copy number variation (CNV) public databases have been used as a reference. Nevertheless, the use of these databases may lead to erroneous results. Our main goal was to explore the limitations of the use of CNV databases, such as the Database of Genomic Variants (DGV), as the reference. To that end, we used pediatric acute lymphoblastic leukemia (ALL) as a model. We analyzed the genome-wide copy number profile of 23 ALL patients and conducted a comparison of the results obtained using the DGV with those obtained using the normal sample from the patient as the reference. Using only the DGV, 19% of alterations and 41% of polymorphisms were erroneously catalogued. Our results support the hypothesis that with the use of databases such as the DGV as the reference, a high percentage of the variations can be erroneously classified. © 2014 Elsevier Inc. Source

Costa D.,Unitat dHematopatologia | Munoz C.,Unitat dHematopatologia | Carrio A.,Unitat dHematopatologia | Nomdedeu M.,Hospital Clinic | And 26 more authors.
Genes Chromosomes and Cancer | Year: 2013

The infrequency of translocations in myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemias (CMML) makes their identification and reporting interesting for the recognition of the recurrent ones and the genes involved in these neoplasias. The aims of this study were to identify new translocations associated with MDS and CMML and to establish their frequency in a cohort of 8,016 patients from the Spanish Group of MDS database. The karyotype was evaluable in 5,654 (70%) patients. Among those, 2,014 (36%) had chromosomal abnormalities, including 213 (10%) translocations identified in 195 patients. The translocations were balanced in 183 (86%) cases and unbalanced in 30 (14%) cases. All chromosomes were found to be involved in translocations, with the single exception of the Y chromosome. The chromosomes most frequently involved were in decreasing frequency: 3, 1, 7, 2, 11, 5, 12, 6, and 17. Translocations were found in karyotypes as the unique chromosomal abnormality (33%), associated with another chromosomal abnormality (11%), as a part of a complex karyotype (17%), and as a part of a monosomal karyotype (38%). There were 155 translocations not previously described in MDS or CMML and nine of them appeared to be recurrent. © 2013 Wiley Periodicals, Inc. Source

Ramos F.,Hospital Universitario Of Leon | Ramos F.,University of Leon | Robledo C.,Research Center del Cancer CSIC | Izquierdo-Garcia F.M.,Hospital Universitario Of Leon | And 17 more authors.
Oncotarget | Year: 2016

The biological and molecular events that underlie bone marrow fibrosis in patients with myelodysplastic syndromes are poorly understood, and its prognostic role in the era of the Revised International Prognostic Scoring System (IPSS-R) is not yet fully determined. We have evaluated the clinical and biological events that underlie bone marrow fibrotic changes, as well as its prognostic role, in a well-characterized prospective patient cohort (n=77) of primary MDS patients. The degree of marrow fibrosis was linked to parameters of erythropoietic failure, marrow cellularity, p53 protein accumulation, WT1 gene expression, and serum levels of CXCL9 and CXCL10, but not to other covariates including the IPSS-R score. The presence of bone marrow fibrosis grade 2 or higher was associated with the presence of mutations in cohesin complex genes (31.5% vs. 5.4%, p=0.006). By contrast, mutations in CALR, JAK2, PDGFRA, PDGFRB, and TP53 were very rare. Survival analysis showed that marrow fibrosis grade 2 or higher was a relevant significant predictor for of overall survival, and independent of age, performance status, and IPSS-R score in multivariate analysis. Source

Serrano M.J.,University of Granada | Ortega F.G.,University of Granada | Alvarez-Cubero M.J.,University of Granada | Nadal R.,Hospital de Barcelona | And 14 more authors.
Oncotarget | Year: 2014

Circulating tumor cells (CTCs) are frequently associated with epithelial-mesenchymal transition (EMT).The objective of this study was to detect EMT phenotype through Vimentin (VIM) and Slug expression in cytokeratin (CK)-negative CTCs in non-metastatic breast cancer patients and to determine the importance of EGFR in the EMT phenomenon. In CK-negative CTCs samples, both VIM and Slug markers were co-expressed in the most of patients. Among patients EGFR+, half of them were positive for these EMT markers. Furthermore, after a systemic treatment 68% of patients switched from CK- to CK+ CTCs. In our experimental model we found that activation of EGFR signaling by its ligand on MCF-7 cells is sufficient to increase EMT phenotypes, to inhibit apoptotic events and to induce the loss of CK expression. The simultaneous detection of both EGFR and EMT markers in CTCs may improve prognostic or predictive information in patients with operable breast cancer. Source

Puiggros A.,Laboratori Of Citogenetica Molecular | Puiggros A.,Cancer Research Program | Delgado J.,University of Barcelona | Rodriguez-Vicente A.,University of Salamanca | And 23 more authors.
British Journal of Haematology | Year: 2013

Losses in 13q as a sole abnormality confer a good prognosis in chronic lymphocytic leukaemia (CLL). Nevertheless, its heterogeneity has been demonstrated and the clinical significance of biallelic 13q deletions remains controversial. We compared the clinico-biological characteristics of a series of 627 patients harbouring isolated 13q deletions by fluorescence in situ hybridization (FISH), either monoallelic (13q × 1), biallelic (13q × 2), or the coexistence of both clones (13qM). The most frequent 13q deletion was 13q × 1 (82·1%), while 13q × 2 and 13qM represented 8·6% and 9·3% of patients respectively. The median percentage of altered nuclei significantly differed across groups: 55%, 72·5% and 80% in 13q × 1, 13q × 2 and 13qM (P < 0·001). However, no significant differences in the clinical outcome among 13q groups were found. From 84 patients with sequential FISH studies, eight patients lost the remaining allele of 13q whereas none of them changed from 13q × 2 to the 13q × 1 group. The percentage of abnormal cells detected by FISH had a significant impact on the five-year cumulative incidence of treatment and the overall survival, 90% being the highest predictive power cut-off. In conclusion, loss of the remaining 13q allele is not enough to entail a worse prognosis in CLL. The presence of isolated 13q deletion can be risk-stratified according to the percentage of altered cells. © 2013 John Wiley & Sons Ltd. Source

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