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Spalt-like proteins are Zinc finger transcription factors from Caenorhabditis elegans to vertebrates, with critical roles in development. In vertebrates, four paralogues have been identified (SALL1-4), and SALL2 is the family's most dissimilar member. SALL2 is required during brain and eye development. It is downregulated in cancer and acts as a tumor suppressor, promoting cell cycle arrest and cell death. Despite its critical functions, information about SALL2 regulation is scarce. Public data indicate that SALL2 is ubiquitinated and phosphorylated in several residues along the protein, but the mechanisms, biological consequences, and enzymes responsible for these modifications remain unknown. Bioinformatic analyses identified several putative phosphorylation sites for Casein Kinase II (CK2) located within a highly conserved C-terminal PEST degradation motif of SALL2. CK2 is a serine/threonine kinase that promotes cell proliferation and survival and is often hyperactivated in cancer. We demonstrated that CK2 phosphorylates SALL2 residues S763, T778, S802, and S806 and promotes SALL2 degradation by the proteasome. Accordingly, pharmacological inhibition of CK2 with Silmitasertib (CX-4945) restored endogenous SALL2 protein levels in SALL2-deficient breast MDA-MB-231, lung H1299, and colon SW480 cancer cells. Silmitasertib induced a methuosis-like phenotype and cell death in SW480 cells. However, the phenotype was significantly attenuated in CRISPr/Cas9-mediated SALL2 knockout SW480 cells. Similarly, Sall2-deficient tumor organoids were more resistant to Silmitasertib-induced cell death, confirming that SALL2 sensitizes cancer cells to CK2 inhibition. We identified a novel CK2-dependent mechanism for SALL2 regulation and provided new insights into the interplay between these two proteins and their role in cell survival and proliferation.

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BACKGROUND: Genetically engineered mice (GEM) are essential tools for understanding gene function and disease modeling. Historically, gene targeting was first done in embryonic stem cells (ESCs) derived from the 129 family of inbred strains, leading to a mixed background or congenic mice when crossed with C57BL/6 mice. Depending on the number of backcrosses and breeding strategies, genomic segments from 129-derived ESCs can be introgressed into the C57BL/6 genome, establishing a unique genetic makeup that needs characterization in order to obtain valid conclusions from experiments using GEM lines. Currently, SNP genotyping is used to detect the extent of 129-derived ESC genome introgression into C57BL/6 recipients; however, it fails to detect novel/rare variants. RESULTS: Here, we present a computational pipeline implemented in the Galaxy platform and in BASH/R script to determine genetic introgression of GEM using next generation sequencing data (NGS), such as whole genome sequencing (WGS), whole exome sequencing (WES) and RNA-Seq. The pipeline includes strategies to uncover variants linked to a targeted locus, genome-wide variant visualization, and the identification of potential modifier genes. Although these methods apply to congenic mice, they can also be used to describe variants fixed by genetic drift. As a proof of principle, we analyzed publicly available RNA-Seq data from five congenic knockout (KO) lines and our own RNA-Seq data from the Sall2 KO line. Additionally, we performed target validation using several genetics approaches. CONCLUSIONS: We revealed the impact of the 129-derived ESC genome introgression on gene expression, predicted potential modifier genes, and identified potential phenotypic interference in KO lines. Our results demonstrate that our new approach is an effective method to determine genetic introgression of GEM.

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The Sall2 transcription factor is deregulated in several cancers; however, little is known about its cellular functions, including its target genes. Recently, we demonstrated that p53 directly regulates Sall2 expression under genotoxic stress. Here, we investigated the role of Sall2 in the context of cellular response to genotoxic stress. In addition, we further examined the Sall2-p53 relationship during genotoxic stress in primary mouse embryo fibroblasts (MEFs), which are derived from Sall2 knockout mice separately, or in combination with the p53ERTAM knock-in mice. We found that the levels of Sall2 mRNA and protein are dynamically modulated in response to doxorubicin. At early times of stress, Sall2 is downregulated, but increases under extension of the stress in a p53-independent manner. Based on caspase-3/7 activities, expression of cleaved poly (ADP-ribose) polymerase, expression of cleaved caspase-3 and induction of proapoptotic proteins, Sall2 expression was correlated with cellular apoptosis. Consequently, Sall2-/- MEFs have decreased apoptosis, which relates with increased cell viability in response to doxorubicin. Importantly, Sall2 was required for apoptosis even in the presence of fully activated p53. Searching for putative Sall2 targets that could mediate its role in apoptosis, we identified proapoptotic NOXA/PMAIP1 (phorbol-12-myristate-13-acetate-induced protein 1). We demonstrated that Sall2 positively regulates Noxa promoter activity. Conserved putative Sall2-binding sites at the NOXA promoter were validated in vitro by electrophoretic mobility shift assay and in vivo by ChIP experiments, identifying NOXA as a novel Sall2 target. In agreement, induction of Noxa protein and mRNA in response to doxorubicin was significantly decreased in Sall2-/- MEFs. In addition, studies in leukemia Jurkat T cells support the existence of the Sall2/Noxa axis, and the significance of this axis on the apoptotic response to doxorubicin in cancer cells. Our study highlights the relevance of Sall2 in the apoptotic response to extended genotoxic stress, which is important for understanding its role in normal physiology and disease.

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INTRODUCCIÓN: Violencia escolar es la persecución física o psicológica de un alumno o alumna contra otro, convirtiéndolo en víctima de repetidos ataques. Es un importante marcador de riesgo de conductas antisociales futuras, y se relaciona con mayor prevalencia de síntomas ansiosos. OBJETIVO: Establecer si existe asociación entre la presencia de ansiedad patológica y la práctica de violencia escolar. MATERIAL Y MÉTODOS: Estudio descriptivo observacional y transversal. Se estudió a 166 alumnos de cuarto a octavo básico, de un colegio particular subvencionado de la comuna de Lo Barnechea, en Santiago de Chile. De ellos, 77 fueron hombres y 89 mujeres, entre 9 y 16 años. Se aplicó la escala de Autoreporte de Ansiedad para Niños y Adolescentes (AANA) y el cuestionario de Maltrato entre Iguales por Abuso de Poder (MIAP). Además, se recopilaron datos tales como sexo, edad, número de personas que viven en el hogar y si vive o no con sus padres. RESULTADOS: De los estudiantes evaluados, el 46,99 por ciento clasificó como testigo de violencia escolar, 19,28 por ciento víctima, 10,84 por ciento agresor, 10,84 por ciento víctima-agresor, y un 12,05 por ciento no clasificó en ninguna categoría. Se obtuvo un 36,1 por ciento de prevalencia de ansiedad patológica en el total de individuos; un 41,67 por ciento en agresores y 30,61 por ciento en no agresores, con chi-cuadrado P > 0,05.DISCUSIÓN: La prevalencia de ansiedad patológica en agresores de violencia escolar es mayor que en quienes no la practican; sin embargo, esta asociación no llega a valores estadísticamente significativos.

INTRODUCTION: Bullying is the physical or psychological persecution of one student against another, making him a victim of recurrent attacks. It is one of the most important risk markers for future antisocial behavior, which has also been associated with higher prevalence of anxiety symptoms. OBJECTIVE: Establish if there is an association between pathological anxiety and bullying. METHODS: This is a descriptive, observational and transversal study. 166 students from fourth to eight grades were studied from a semi private school from Lo Barnechea, Santiago, Chile. From this population, 77 were male and89 female, between 9 and 16 years old. The Anxiety Scale for Children and Adolescents (AAA) and the Survey of High School Bullying Abuse of Power questionnaires were applied. Also, data such as sex, age, number of people who are living in their homes and whether they live with their parents or not was collected. RESULTS: From the students evaluated, 46.99 percent classified as bullying witnesses, 19.28 percent as victims, 10.84 percent as aggressors, 10.84 percent aggressor-victim and 12.05 percent didn't classify in any category. A 36.1 percent prevalence of pathologic anxiety was obtained from the totality of individuals. In the aggressor category 41.67 percent had pathological anxiety and 30.61 percent in non-aggressors, with a chi-square P > 0.05. DISCUSSION: Prevalence of pathological anxiety is higher in the aggressor than in the non-aggressor group, however this association is statistically non-significant

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The effect of verapamil and nimodipine on verbal learning was evaluated in a double-blind clinical trial. Thirty-seven healthy volunteers were distributed in three groups to receive a treatment with nimodipine, verapamil or placebo. Neither verapamil nor nimodipine modifies verbal learning as measured by the selective remembering test of Buschke and Fuld.

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