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Histone methyltransferases (HMTs) are important epigenetic regulators of gene transcription and are disrupted at the genomic level in a spectrum of human tumors including haematological malignancies. Using high-resolution SNP-arrays, we identified recurrent deletions of the SETD2 locus in 3% (8/261) of chronic lymphocytic leukemia (CLL) patients. Further validation in two independent cohorts showed that SETD2 deletions were associated with loss of TP53, genomic complexity and chromothripsis. With next generation sequencing we detected mutations of SETD2 in an additional 3.8% of patients (23/602). In most cases, SETD2-deletions or mutations were often observed as a 56 clonal event and always as a mono-allelic lesion, leading to reduced mRNA expression in SETD2-disrupted cases. Patients with SETD2 abnormalities and wild-type TP53 and ATM from five clinical trials employing chemotherapy or chemo-immunotherapy, had reduced progression-free and overall survival compared to cases wild-type for all three genes. Consistent with its postulated role as a tumor suppressor, our data highlights SETD2 aberration as a recurrent, early loss-of-function event in CLL pathobiology linked to aggressive disease.

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic disorder with heterogeneous clinical, morphological and genetic characteristics. Clonal cytogenetic abnormalities are found in 20-30% of patients with CMML. Patients with low risk cytogenetic features (normal karyotype and isolated loss of Y chromosome) account for similar to 80% of CMML patients and often fall into the low risk categories of CMML prognostic scores. We hypothesized that single nucleotide polymorphism arrays (SNP-A) karyotyping could detect cryptic chromosomal alterations with prognostic impact in these subgroup of patients. SNP-A were performed at diagnosis in 128 CMML patients with low risk karyotypes or uninformative results for conventional G-banding cytogenetics (CC). Copy number alterations (CNAs) and regions of copy number neutral loss of heterozygosity (CNN-LOH) were detected in 67% of patients. Recurrent CNAs included gains in regions 8p12 and 21q22 as well as losses in 10q21.1 and 12p13.2. Interstitial CNN-LOHs were recurrently detected in the following regions: 4q24-4q35, 7q32.1-7q36.3, and 11q13.3-11q25. Statistical analysis showed that some of the alterations detected by SNP-A associated with the patients' outcome. A shortened overall survival (OS) and progression free survival (PFS) was observed in cases where the affected size of the genome (considering CNAs and CNN-LOHs) was >11 Mb. In addition, presence of interstitial CNN-LOH was predictive of poor OS. Presence of CNAs (>= 1) associated with poorer OS and PFS in the patients with myeloproliferative CMML. Overall, SNP-A analysis increased the diagnostic yield in patients with low risk cytogenetic features or uninformative CC and added prognostic value to this subset of patients. (C) 2015 Wiley Periodicals, Inc.

We report on markedly different frequencies of genetic lesions within subsets of chronic lymphocytic leukemia patients carrying mutated or unmutated stereotyped B-cell receptor immunoglobulins in the largest cohort (n=565) studied for this purpose. By combining data on recurrent gene mutations (BIRC3, MYD88, NOTCH1, SF3B1 and TP53) and cytogenetic aberrations, we reveal a subset-biased acquisition of gene mutations. More specifically, the frequency of NOTCH1 mutations was found to be enriched in subsets expressing unmutated immunoglobulin genes, i.e. #1, #6, #8 and #59 (22-34%), often in association with trisomy 12, and was significantly different (P

Histone methyltransferases (HMTs) are important epigenetic regulators of gene transcription and are disrupted at the genomic level in a spectrum of human tumours including haematological malignancies. Using high-resolution single nucleotide polymorphism (SNP) arrays, we identified recurrent deletions of the SETD2 locus in 3% (8/261) of chronic lymphocytic leukaemia (CLL) patients. Further validation in two independent cohorts showed that SETD2 deletions were associated with loss of TP53, genomic complexity and chromothripsis. With next-generation sequencing we detected mutations of SETD2 in an additional 3.8% of patients (23/602). In most cases, SETD2 deletions or mutations were often observed as a clonal event and always as a mono-allelic lesion, leading to reduced mRNA expression in SETD2-disrupted cases. Patients with SETD2 abnormalities and wild-type TP53 and ATM from five clinical trials employing chemotherapy or chemo-immunotherapy had reduced progression-free and overall survival compared with cases wild type for all three genes. Consistent with its postulated role as a tumour suppressor, our data highlight SETD2 aberration as a recurrent, early loss-of-function event in CLL pathobiology linked to aggressive disease., This work was funded by Bloodwise (11052, 12036), the Kay Kendall Leukaemia Fund (873), Cancer Research UK (C34999/A18087, ECMC C24563/A15581), Wessex Medical Research and the Bournemouth Leukaemia Fund. SS is supported by the Else Kröner-FreseniusStiftung (2012_A146) and Deutsche Forschungsgemeinschaft (SFB 1074 projects B1, B2). The LRF CLL4 trial was funded by a core grant from Leukaemia and Lymphoma Research. DG and DC acknowledge the support by The Royal Marsden Hospital and The Institute of Cancer Research National Institute of Health Research Biomedical Research Center. RR is supported by the Swedish Cancer Society, the Swedish Research Council, Science for Life Laboratory, Uppsala University, Uppsala University Hospital, and the Lion’s Cancer Research Foundation, Uppsala.

La expresión de VEGFA y sus receptores en las células tumorales de pulmón puede indicar que además de la regulación paracrina sobre las células endoteliales, exista otra de tipo autocrino implicada en la progresión tumoral. La activación del loop autocrino en las células tumorales puede afectar de manera diferente al fenotipo tumoral dependiendo de la histología de cada tumor. Para contrastar esta hipótesis se propusieron los siguientes objetivos: 1. Determinación del valor pronóstico de VEGFA y sus receptores en estadios precoces de NSCLC. 2. Análisis de la expresión de VEGFA, sus isoformas y receptores en células de pulmón normal y líneas celulares tumorales. Estudio del loop autocrino en las líneas de pulmón. 3. Generación de modelos celulares de modificación de la expresión de VEGF-R2 y evaluación de su efecto sobre las células tumorales. 4. Estudio del efecto de las terapias anti-VEGFA/VEGFR en modelos murinos de cáncer de pulmón (diferencias entre ADC y CE). 5. Estudio del papel de las isoformas b de VEGFA en NSCLC.

Background: Different isoforms of VEGF-A (mainly VEGF121, VEGF165 and VEGF189) have been shown to display particular angiogenic properties in the generation of a functional tumor vasculature. Recently, a novel class of VEGF-A isoforms, designated as VEGFxxxb, generated through alternative splicing, have been described. Previous studies have suggested that these isoforms may inhibit angiogenesis. In the present work we have produced recombinant VEGF121/165b proteins in the yeast Pichia pastoris and constructed vectors to overexpress these isoforms and assess their angiogenic potential. Results: Recombinant VEGF121/165b proteins generated either in yeasts or mammalian cells activated VEGFR2 and its downstream effector ERK1/2, although to a lesser extent than VEGF165. Furthermore, treatment of endothelial cells with VEGF121/165b increased cell proliferation compared to untreated cells, although such stimulation was lower than that induced by VEGF165. Moreover, in vivo angiogenesis assays confirmed angiogenesis stimulation by VEGF121/165b isoforms. A549 and PC-3 cells overexpressing VEGF121b or VEGF165b (or carrying the PCDNA3.1 empty vector, as control) and xenotransplanted into nude mice showed increased tumor volume and angiogenesis compared to controls. To assess whether the VEGFxxxb isoforms are differentially expressed in tumors compared to healthy tissues, immunohistochemical analysis was conducted on a breast cancer tissue microarray. A significant increase (p < 0.05) in both VEGFxxxb and total VEGF-A protein expression in infiltrating ductal carcinomas compared to normal breasts was observed. A positive significant correlation (r = 0.404, p = 0.033) between VEGFxxxb and total VEGF-A was found. Conclusions: Our results demonstrate that VEGF121/165b are not anti-angiogenic, but weakly angiogenic isoforms of VEGF-A. In addition, VEGFxxxb isoforms are up-regulated in breast cancer in comparison with non malignant breast tissues. These results are to be taken into account when considering a possible use of VEGF121/165b-based therapies in patients.