34 research outputs found
ERBB2 in Cat Mammary Neoplasias Disclosed a Positive Correlation between RNA and Protein Low Expression Levels: A Model for erbB-2 Negative Human Breast Cancer
Human ERBB2 is a proto-oncogene that codes for the erbB-2 epithelial growth factor receptor. In human breast cancer (HBC), erbB-2 protein overexpression has been repeatedly correlated with poor prognosis. In more recent works, underexpression of this gene has been described in HBC. Moreover, it is also recognised that oncogenes that are commonly amplified or deleted encompass point mutations, and some of these are associated with HBC. In cat mammary lesions (CMLs), the overexpression of ERBB2 (27%–59.6%) has also been described, mostly at the protein level and although cat mammary neoplasias are considered to be a natural model of HBC, molecular information is still scarce. In the present work, a cat ERBB2 fragment, comprising exons 10 to 15 (ERBB2_10–15) was achieved for the first time. Allelic variants and genomic haplotype analyses were also performed, and differences between normal and CML populations were observed. Three amino acid changes, corresponding to 3 non-synonymous genomic sequence variants that were only detected in CMLs, were proposed to damage the 3D structure of the protein. We analysed the cat ERBB2 gene at the DNA (copy number determination), mRNA (expression levels assessment) and protein levels (in extra- and intra protein domains) in CML samples and correlated the last two evaluations with clinicopathological features. We found a positive correlation between the expression levels of the ERBB2 RNA and erbB-2 protein, corresponding to the intracellular region. Additionally, we detected a positive correlation between higher mRNA expression and better clinical outcome. Our results suggest that the ERBB2 gene is post-transcriptionally regulated and that proteins with truncations and single point mutations are present in cat mammary neoplastic lesions. We would like to emphasise that the recurrent occurrence of low erbB-2 expression levels in cat mammary tumours, suggests the cat mammary neoplasias as a valuable model for erbB-2 negative HBC.POCI/CVT/62940/2004 and by the PhD grants (SFRH/BD/23406/2005 and SFRH/BD/31754/2006, of the Science and Technology Foundation (FCT) from Portugal
Identification of Vascular and Hematopoietic Genes Downstream of etsrp by Deep Sequencing in Zebrafish
The transcription factor etsrp/Er71/Etv2 is a master control gene for vasculogenesis in all species studied to date. It is also required for hematopoiesis in zebrafish and mice. Several novel genes expressed in vasculature have been identified through transcriptional profiling of zebrafish embryos overexpressing etsrp by microarrays. Here we re-examined this transcriptional profile by Illumina RNA-sequencing technology, revealing a substantially increased number of candidate genes regulated by etsrp. Expression studies of 50 selected candidate genes from this dataset resulted in the identification of 39 new genes that are expressed in vascular cells. Regulation of these genes by etsrp was confirmed by their ectopic induction in etsrp overexpressing and decreased expression in etsrp deficient embryos. Our studies demonstrate the effectiveness of the RNA-sequencing technology to identify biologically relevant genes in zebrfish and produced a comprehensive profile of genes previously unexplored in vascular endothelial cell biology
Gut mucosal DAMPs in IBD: From mechanisms to therapeutic implications
Endogenous damage-associated molecular patterns (DAMPs) are released during tissue damage and have increasingly recognized roles in the etiology of many human diseases. The inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn’s disease (CD), are immune-mediated conditions where high levels of DAMPs are observed. DAMPs such as calprotectin (S100A8/9) have an established clinical role as a biomarker in IBD. In this review, we use IBD as an archetypal common chronic inflammatory disease to focus on the conceptual and evidential importance of DAMPs in pathogenesis and why DAMPs represent an entirely new class of targets for clinical translation. </p
Understanding the functional properties of tools: chimpanzees (Pan troglodytes) and capuchin monkeys (Cebus apella) attend to tool features differently
We examined whether eight capuchins and eight chimpanzees were able to retrieve a reward placed inside a tube, of varying length, by selecting the correct stick from different sets of three sticks differing in length (functional feature) and handle (non-functional feature). Moreover, to investigate whether seeing the stick inside the tube (visual feedback) improves performance, half of the subjects were tested with a transparent apparatus and the other half with an opaque apparatus. Phase 1 included (a) Training 1 in which each stick had a different handle and (b) Transfer 1 in which the handles were switched among sticks, so that the functional tool had the same length but a different handle than before. The seven chimpanzees and one capuchin that passed Transfer 1 received Transfer 2. The other subjects received (a) Training 2, which used the same sticks from Phase 1 with handles switched in every trial, and (b) Transfer 2 in which the tube was longer, all sticks had the same new handle, and the formerly longest tool became intermediate in length. Eight chimpanzees and three capuchins passed Transfer 2. Results showed that (1) chimpanzees applied relational structures in tool using tasks more quickly than capuchins and (2) capuchins required more varied experience to attend to the functional feature of the tool. Interestingly, visual feedback did not improve performance in either species