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Mutations in genes encoding subunits of the SWI/SNF chromatin remodeling complex are frequently found in different human cancers. While the tumor suppressor function of this complex is widely established in solid tumors, its role in hematologic malignancies is largely unknown. Recurrent point mutations in BCL7Agene, encoding a subunit of the SWI/SNF complex, have been reported in diffuse large B-cell lymphoma (DLBCL), but their functional impact remains to be elucidated. Here we show that BCL7A often undergoes biallelic inactivation, including a previously unnoticed mutational hotspot in the splice donor site of intron one. The splice site mutations render a truncated BCL7A protein, lacking a portion of the amino-terminal domain. Moreover, restoration of wild-type BCL7A expression elicits a tumor suppressor-like phenotype in vitro and in vivo. In contrast, splice site mutations block the tumor suppressor function of BCL7A by preventing its binding to the SWI/SNF complex. We also show that BCL7A restoration induces transcriptomic changes in genes involved in B-cell activation. In addition, we report that SWI/SNF complex subunits harbor mutations in more than half of patients with germinal center B-cell (GCB)-DLBCL. Overall, this work demonstrates the tumor suppressor function of BCL7A in DLBCL, and highlights that the SWI/SNF complex plays a relevant role in DLBCL pathogenesis.

Epigenetic regulators that exhibit aberrant enzymatic activities or expression profiles are potential therapeutic targets for cancers. Specifically, enzymes responsible for methylation at histone-3 lysine-9 (like G9a) and aberrant DNA hypermethylation (DNMTs) have been implicated in a number of cancers. Recently, molecules bearing a 4-aminoquinoline scaffold were reported as dual inhibitors of these targets and showed a significant in vivo efficacy in animal models of hematological malignancies. Here, we report a detailed exploration around three growing vectors born by this chemotype. Exploring this chemical space led to the identification of features to navigate G9a and DNMT1 biological spaces: not only their corresponding exclusive areas, selective compounds, but also common spaces. Thus, we identified from selective G9a and first-in-class DNMT1 inhibitors, >1 log unit between their IC50values, with IC50< 25 nM (e.g., 43and 26, respectively) to equipotent inhibitors with IC50< 50 nM for both targets (e.g., 13). Their ADME/Tox profiling and antiproliferative efficacies, versus some cancer cell lines, are also reported.

Using knowledge- and structure-based approaches, we designed and synthesized reversible chemical probes that simultaneously inhibit the activity of two epigenetic targets, histone 3 lysine 9 methyltransferase (G9a) and DNA methyltransferases (DNMT), at nanomolar ranges. Enzymatic competition assays confirmed our design strategy: substrate competitive inhibitors. Next, an initial exploration around our hit 11was pursued to identify an adequate tool compound for in vivo testing. In vitro treatment of different hematological neoplasia cell lines led to the identification of molecules with clear antiproliferative efficacies (GI50values in the nanomolar range). On the basis of epigenetic functional cellular responses (levels of lysine 9 methylation and 5-methylcytosine), an acceptable therapeutic window (around 1 log unit) and a suitable pharmacokinetic profile, 12was selected for in vivo proof-of-concept (Nat. Commun.2017, 8, 15424). Herein, 12achieved a significant in vivo efficacy: 70% overall tumor growth inhibition of a human acute myeloid leukemia (AML) xenograft in a mouse model.

In hematopoietic malignancies, oncogenic alterations interfere with cellular differentiation and lead to tumoral development. Identification of the proteins regulating differentiation is essential to understand how they are altered in malignancies. Chronic myelogenous leukemia (CML) is a biphasic disease initiated by an alteration taking place in hematopoietic stem cells. CML progresses to a blast crisis (BC) due to a secondary differentiation block in any of the hematopoietic lineages. However, the molecular mechanisms of CML evolution to T-cell BC remain unclear. Here, we have profiled the changes in DNA methylation patterns in human samples from BC-CML, in order to identify genes whose expression is epigenetically silenced during progression to T-cell lineage-specific BC. We have found that the CpG-island of the ENGRAILED-2(EN2) gene becomes methylated in this progression. Afterwards, we demonstrate that En2is expressed during T-cell development in mice and humans. Finally, we further show that genetic deletion of En2in a CML transgenic mouse model induces a T-cell lineage BC that recapitulates human disease. These results identify En2as a new regulator of T-cell differentiation whose disruption induces a malignant T-cell fate in CML progression, and validate the strategy used to identify new developmental regulators of hematopoiesis.

We find the behavior of the solution of the optimal transport problem for the Euclidean distance (and its approximation by p−Laplacian problems) when the involved measures are supported in a domain that is contracted in one direction.

Sequence variants at the TERT-CLPTM1L locus in chromosome 5p have been recently associated with disposition for various cancers. Here we show that this locus including the gene encoding the telomerase reverse-transcriptase TERT at 5p13.33 is rarely but recurrently targeted by somatic chromosomal translocations to IGH and non-IG loci in B-cell neoplasms, including acute lymphoblastic leukemia, chronic lymphocytic leukemia, mantle cell lymphoma and splenic marginal zone lymphoma. In addition, cases with genomic amplification of TERT locus were identified. Tumors bearing chromosomal aberrations involving TERT showed higher TERT transcriptional expression and increased telomerase activity. These data suggest that deregulation of TERT gene by chromosomal abnormalities leading to increased telomerase activity might contribute to B-cell lymphomagenesis.

Abstract: We tested the hypothesis that fertilized containerized Pinus canariensis seedlings increases survival when planted in semiarid sites through the improvement of their physiological status during the establishment phase by an increment in root growth. Seedlings were cultured under two different regimes: traditional (in non-fertilized natural soil) and alternative (in fertilized peat). Morphological attributes and nitrogen content were measured before planting. Measurements of survival and growth in the plantation were made periodically for 2 years and physiological plant responses (leaf water potential, gas exchange and chlorophyll fluorescence) during the third summer after planting were tested and finally a set of plants were excavated to measure the same parameters as before planting. Seedlings cultivated using fertilized peat achieved the highest values for all of evaluated parameters. During the third dry season, big seedlings exhibited better physiological status. Therefore, enhanced root growth can result in better water uptake during the dry period thereby increasing survival and growth in the next few years after planting. A feed-back physiological model is proposed to explain P. canariensis establishment in a semiarid environment.

Abstract: We studied correlates of habitat use of riparian feral American minkMustela vison Schreber, 1777 during winter in Biscay (Northern Iberian Peninsula). We live-trapped and radio-tagged 10 American mink (5 males and 5 females) and successfully radiotracked 7 of them (3 males and 4 females). During resting periods both sexes selected areas with dense scrub and near to deep waters. Both sexes used underground dens as well as resting sites located above the ground, but during cold days females rested in buildings much more often than males. Active females used areas of dense scrub, and males used large scrub patches. The results are interpreted in the light of mink hunting techniques and perceived predation risk: on larger scales, mink select areas primarily by food abundance, while on very small scales they use scrub and similar structures providing safe areas to hunt, forage and rest. The strong preference for banks with dense scrub provides options for management of the species.

Since the XIX century, there is a controversy about the existence of biennial maturation of the acorns in Quercus suber L. While some authors recognised biennial cycles as an adaptation to habitats with short vegetative periods, other authors discarded the biennial pattern. Successive flowering events from spring to autumn and annual acorn ripening are proposed as an explanation of the multiple acorn crops typical of Iberian forests. To clarify this discussion, the presence of annual and biennial acorns was assessed in seven cork oak stands, covering a wide range of environmental conditions. In each stand, 100 individuals were sampled once in spring and once in autumn. Biennial acorns were observed with variable frequencies in all populations. There was a significant and positive relationship between latitude and the percentage of trees with biennial acorns within northern and central populations. On the contrary, this trend was not significant among southern populations. The hypothesis that the presence of biennial acorns in Quercus suber is related to individual female flowering phenology was confirmed in four populations located in the southwestern Iberian Peninsula. Unregarding local differences in the distribution of phenological stages anticipated trees bore significantly less biennial acorns than delayed individuals of the same stand. This result is coherent with the idea that the length of the vegetative period plays a crucial role in the frequency of annual and biennial acorn ripening patterns. The relationship between annual and biennial ripening cycles and the multiple acorn crops is discussed.

Shoot elongation and flowering were assessed for a season (January–November) in 25 grafts from five clones of Pinus halepensis growing in a seed orchard. A co-dominant shoot from the upper crown and a dominated, low shoot were measured from each ramet. Upper shoots elongated continuously from a variable onset date between January and March and followed a logistic function against Julian day and a Gompertz function against heat sum above 0°C. Three to seven (averaging five) successive cycles were formed through the growing season; usually, two of them were preformed in the terminal bud (spring cycles) and one to four were neo-formed, summer cycles. The number of summer cycles and their contribution to the annual shoot growth were the only variables with a significant clonal influence. Ovulate strobili appeared from February to April and in October. Some ramets showing two female flowering cycles in the same shoot were observed. Lower shoots, bearing pollinate strobili always displayed a single spring cycle preformed in the winter bud.

This study explores whether the presence of somatic mutations or a biased use of IgVHgenes were associated with the clinical features in a series of 96 patients with mantle cell lymphoma (MCL). The cases were studied by seminested polymerase chain reaction using primers from the FR1 and JHregions. There was an unexpectedly high frequency of somatic mutations, with 29 of 103 sequences showing more than 2% of mutations. Biased usage of specific VHsegments was also found; the most widely used genes in this series wereVH3-21(10 cases),VH3-23(9 cases),VH4-34(11 cases), andVH4-59(9 cases).VHmutation frequency, taking into account different thresholds, did not distinguish different overall survival probabilities. Nevertheless, a more frequent use ofVH3-21or VH4-59(8 of 18) was observed in the group of long-term survivors (18 cases > 5 years; P< .01). None of these long-term survivors presented the VH3-23gene rearrangement. As in other lymphoproliferative disorders, the expression of CD38 or p53 or both was associated with a poorer survival probability. This nonrandom usage of IgVHsegments suggests that specific antigens may play a pathogenically relevant role in the genesis or progression of subsets of MCL cases and may help in distinguishing a significant group of MCL long-term survivors.

This study explores whether the presence of somatic mutations or a biased use of IgVH genes were associated with the clinical features in a series of 96 patients with mantle cell lymphoma (MCL). The cases were studied by seminested polymerase chain reaction using primers from the FR1 and JHregions. There was an unexpectedly high frequency of somatic mutations, with 29 of 103 sequences showing more than 2% of mutations. Biased usage of specific VH segments was also found; the most widely used genes in this series wereVH3-21 (10 cases),VH3-23 (9 cases),VH4-34 (11 cases), andVH4-59 (9 cases).VH mutation frequency, taking into account different thresholds, did not distinguish different overall survival probabilities. Nevertheless, a more frequent use ofVH3-21 or VH4-59 (8 of 18) was observed in the group of long-term survivors (18 cases > 5 years; P < .01). None of these long-term survivors presented the VH3-23 gene rearrangement. As in other lymphoproliferative disorders, the expression of CD38 or p53 or both was associated with a poorer survival probability. This nonrandom usage of IgVH segments suggests that specific antigens may play a pathogenically relevant role in the genesis or progression of subsets of MCL cases and may help in distinguishing a significant group of MCL long-term survivors.

Many B-cell malignancies bear chromosomal translocations juxtaposing immunoglobulin (IG) genes with oncogenes, resulting in deregulated expression of the latter. Translocations affecting the IG heavy chain (IGH) locus in chromosomal region 14q32 are most prevalent. However, variant translocations involving the IG kappa (IGK) locus in 2p12 or the IG lambda (IGL) locus in 22q11 occur recurrently in B-cell neoplasias. No routine methods for the detection of all breakpoints involving IG light chain loci independently of the translocation partner have been described. For this reason, we have designed 2 novel interphase fluorescence in situ hybridization (FISH) assays using differentially labeled probes flanking the IGK and IGL locus, respectively. Based on extensive control studies, the diagnostic thresholds for the detection of breakpoints were set at 0.3% for IGK and 1.4% for IGL. Fifteen cases of B-cell malignancies with cytogenetically detectable chromosomal abnormalities in 2p11-14 were investigated with the FISH assay for IGK. Breakpoints affecting the IGK locus were detected in 7 cases including all 4 variant Burkitt's translocations t(2;8)(p12;q24) and a variant BCL2-associated translocation t(2;18)(p12;q21). Other translocation partners were chromosome bands 7q21 and 16q24. Ten cases with abnormalities in 22q11-12 were investigated with the FISH assay for IGL. Breakpoints in the IGL locus were diagnosed in 7 cases including both variant Burkitt's translocations t(8;22)(q24;q11) and a t(3;22)(q27;q11) involving the BCL6 locus. Other translocation partners were 2p13-14, 4q13 and 16p12. Our results show that these FISH assays provide flexible, simple and reliable tools in the diagnosis and characterization of genetic changes in B-cell malignancies. © 2002 Wiley-Liss, Inc.

Background:Several syndromes in which melanocytic nevi and scoliosis were present in the same patient have been described. No control study has been made to date to determine whether there is a relationship between these disorders. Objective:We attempted to demonstrate the association between acquired melanocytic nevi (AMN) and idiopathic scoliosis (IS). Methods:We studied 93 patients with IS, aged 10 to 18 years, from our hospital. Controls were randomly selected from 2 schools; Adam's forward bending test was used to exclude persons with clinical scoliosis, and the control group finally comprised 101 pupils. An observational, cross-sectional study was done. All AMN 2 mm or larger observed on the body were counted by one dermatologist. Other variables reported as risk factors in the number of nevi were also considered. Reliability of AMN counts was previously demonstrated. Results:The median number of AMN was 18 (range, 10-42) in the IS group and 8 (range, 3-13) in controls (P< .001). The persons with scoliosis had more non-AMN dermatologic lesions than the controls (P< .05). Light phenotype correlated with many AMN. On multivariate analysis only scoliosis and age accounted independently for the number of AMN. Conclusion:IS is associated with many AMN. Multiple AMN may become a diagnostic marker for IS, and these two malformations might constitute a syndromic association. (J Am Acad Dermatol 2001;45:35-43.)

Splenic marginal zone lymphoma (SMZL) has recently been recognized in the World Health Organization classification of hematological diseases as distinct type of non-Hodgkin’s lymphoma. In contrast to the well-established chromosomal changes associated with other B-cell non-Hodgkin’s lymphoma, few genetic alterations have been found associated with SMZL. The aim of our study was to analyze by comparative genomic hybridization (CGH) the chromosomal imbalances in 29 patients with SMZL and to correlate these findings with clinical and biological characteristics and patient outcome. In 21 cases, cytogenetic studies were simultaneously performed. Most of the patients (83%) displayed genomic imbalances. A total of 111 DNA copy number changes were detected with a median of four abnormalities per case (range, 1 to 12). Gains (n= 92) were more frequent than losses (n= 16), while three high-level amplifications (3q26-q29, 5p11-p15, and 17q22-q25) were observed. The most frequent gains involved 3q (31%), 5q (28%), 12q and 20q (24% each), 9q (21%), and 4q (17%). Losses were observed in 7q (14%) and 17p (10%). SMZL patients with genetic losses had a shorter survival than the remaining SMZL patients (P< 0.05). In summary, chromosomal imbalances in regions 3q, 4q, 5q, 7q, 9q, 12q, and 20q have been detected by CGH in SMZL. Patients with SMZL displaying genetic losses by CGH had a short survival.

The development and construction of a specific instrument for measuring quality of life in adolescents with spine defomities was investigated.

Abstract:  Resinous heartwood (lightwood) is an important feature in Pinus canariensis (Canary Island pine), as this wood has very good mechanical and aesthetic characteristics. In order to determine anatomical traits related to lightwood formation, structure of axial resin canals, xylem cell connections and cell contents were studied on wood samples from sites with different environments. Specimens consisted of radial wood cores and stem discs at breast height. The unknown presence of a wide parenchymatous sheath in axial resin canals is highlighted, and a general description of this formation is provided. Quantitative anatomical traits were examined to explain deviations of heartwood radius from the values predicted by a regression model. Thus, percentage of rays and axial parenchyma were assayed in ten individuals. Those with a larger heartwood than predicted by their age and growth tend to display a higher percentage of axial parenchyma in the inner xylem (5th growth ring). More than 40% of heartwood′s dry weight is due to extractives, mainly resin, fats and phenolic compounds, ranging up to 4% in sapwood. This intense soaking is explained by the high proportion of living cells in the xylem, and their capability to accumulate large quantities of reserve starch. These traits are closely linked to other important features of the species, such as stem sprouting and resistance to extreme wounding.

Pese a la gran frecuencia de problemas de salud mental entre los consultantes de atención primaria, persiste el problema de unos inadecuados diagnóstico y tratamiento. Se necesita una buena capacitación de los médicos de familia para el manejo de estos trastornos, a fin de minimizar su impacto sanitario, económico y social. Entre otros elementos, se considera relevante la cooperación con los servicios de salud mental, para la cual existen diferentes modelos. Nuestro departamento de salud inició en 2006 una colaboración estable según el modelo de enlace. Se han obtenido resultados positivos en términos de reducción de demora para las primeras visitas al especialista y de aumento de la satisfacción de los profesionales, aunque deben interpretarse con cautela. Recientemente se han acumulado evidencias sobre la utilidad del modelo colaborativo, aunque su evaluación y extrapolación son complejas. Nos proponemos ahondar en la evaluación de nuestro modelo, de manera análoga a otras iniciativas de nuestro entorno.

No relevant conflicts of interest to declare.

The epigenomic changes that occur during the process of cellular differentiation, such as in the blood cell lineage, are currently not well understood, especially at distant regulatory regions such as enhancer sequences. To study the effects of DNA methylation on cellular (de)differentiation, we have used a human B Cell Acute Lymphoblastic Leukemia model of transdifferentiation (BLaER1), which has an estradiol-inducible CEBPA construct that allows the conversion of leukemic B cells to non-tumorigenic macrophage-like cells. By analyzing the DNA methylation landscape of these cells at different time points of transdifferentiation with an Illumina EPIC methylation array, we have found enhancer-associated CpGs that shifts their methylation levels at the end of the transdifferentiation. By merging these results with the data obtained by Genome-wide Chromosome Conformation Capture Capture (Hi-C) in naive B cells and macrophages, we studied the putative interaction between several gene-promoters and our differentially methylated CpGs. We then proceed further to characterize the impact of the observed interactions on gene expression. We have identified the DNA methylation dependent enhancer interactomes of B-cells and macrophages. These target genes are related with vesicle trafficking, endocytosis and immune response. Our data highlight the role of DNA methylation to determine cell identity in the blood cell lineage.

A group of 102 brace-treated adolescents, aged 10–19 years with spine deformities participated in a cross-sectional study.