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1.
Front Mol Biosci ; 9: 818552, 2022.
Article in English | MEDLINE | ID: mdl-35340765

ABSTRACT

The extracellular matrix (ECM) plays an undisputable role in tissue homeostasis and its deregulation leads to altered mechanical and biochemical cues that impact cancer development and progression. Herein, we undertook a novel approach to address the role of gastric ECM in tumorigenesis, which remained largely unexplored. By combining decellularization techniques with a high-throughput quantitative proteomics approach, we have performed an extensive characterization of human gastric mucosa, uncovering its composition and distribution among tumor, normal adjacent and normal distant mucosa. Our results revealed a common ECM signature composed of 142 proteins and indicated that gastric carcinogenesis encompasses ECM remodeling through alterations in the abundance of 24 components, mainly basement membrane proteins. Indeed, we could only identify one de novo tumor-specific protein, the collagen alpha-1(X) chain (COL10A1). Functional analysis of the data demonstrated that gastric ECM remodeling favors tumor progression by activating ECM receptors and cellular processes involved in angiogenesis and cell-extrinsic metabolic regulation. By analyzing mRNA expression in an independent GC cohort available at the TGCA, we validated the expression profile of 12 differentially expressed ECM proteins. Importantly, the expression of COL1A2, LOX and LTBP2 significantly correlated with high tumor stage, with LOX and LTBP2 further impacting patient overall survival. These findings contribute for a better understanding of GC biology and highlight the role of core ECM components in gastric carcinogenesis and their clinical relevance as biomarkers of disease prognosis.

2.
J Agric Food Chem ; 66(28): 7275-7285, 2018 Jul 18.
Article in English | MEDLINE | ID: mdl-29925239

ABSTRACT

In the present work, hydrophobic nanoprecipitates (HNPs) of inclusion complexes formed between ß-cyclodextrin (ßCD) and the avermectins (AVMs) named eprinomectin (EPRI) and ivermectin (IVER) were synthesized and characterized, and their larvicidal activity against Aedes aegypti and human safety against fibroblasts were evaluated. Initially, thermogravimetric analysis/differential thermal analysis data revealed that inclusion increased the thermal stability of AVMs in the presence of ßCD. Nuclear magnetic resonance experiments and density functional theory calculations pointed out the inclusion of the benzofuran ring of the two AVMs in the ßCD cavity. Isothermal titration calorimetry experiments allowed identification of different binding constants for EPRI/ßCD ( Kb = 1060) and ßCD/IVER ( Kb = 1700) systems, despite the structural similarity. Dynamic light scattering titrations of AVMs' dimethyl sulfoxide solution in ßCD aqueous solution demonstrated that the formed HNPs have lower sizes in the presence of ßCD. Finally, the inclusion of EPRI in ßCD increased its larval toxicity and reduced its human cytotoxicity, while for IVER/ßCD no beneficial effect was observed upon inclusion. These results were rationalized in terms of structural differences between the two molecules. Finally, the EPRI/ßCD complex has great potential as an insecticide against A. aegypti larvae with high human safety.


Subject(s)
Aedes/drug effects , Fibroblasts/drug effects , Insecticides/toxicity , Ivermectin/analogs & derivatives , Larva/drug effects , Nanostructures/toxicity , beta-Cyclodextrins/pharmacology , Aedes/growth & development , Animals , Cell Survival/drug effects , Female , Hydrophobic and Hydrophilic Interactions , Insecticides/chemistry , Ivermectin/chemistry , Ivermectin/toxicity , Larva/growth & development , Magnetic Resonance Spectroscopy , Male , Nanostructures/chemistry , Solubility , beta-Cyclodextrins/chemistry
3.
Hum Mol Genet ; 24(20): 5891-900, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26246502

ABSTRACT

Epithelial-cadherin (Ecad) deregulation affects cell-cell adhesion and results in increased invasiveness of distinct human carcinomas. In gastric cancer, loss of Ecad expression is a common event and is associated with disease aggressiveness and poor prognosis. However, the molecular mechanisms underlying the invasive process associated to Ecad dysfunction are far from understood. We hypothesized that deregulation of cell-matrix interactions could play an important role during this process. Thus, we focussed on LM-332, which is a major matrix component, and in Ecad/LM-332 crosstalk in the process of Ecad-dependent invasion. To verify whether matrix deregulation was triggered by Ecad loss, we used the Drosophila model. To dissect the key molecules involved and unveil their functional significance, we used gastric cancer cell lines. The relevance of this relationship was then confirmed in human primary tumours. In vivo, Ecad knockdown induced apoptosis; nonetheless, at the invasive front, cells ectopically expressed Laminin A and ßPS integrin. In vitro, we demonstrated that, in two different gastric cancer cell models, Ecad-defective cells overexpressed Laminin γ2 (LM-γ2), ß1 and ß4 integrin, when compared with Ecad-competent ones. We showed that LM-γ2 silencing impaired invasion and enhanced cell death, most likely via pSrc and pAkt reduction, and JNK activation. In human gastric carcinomas, we found a concomitant decrease in Ecad and increase in LM-γ2. This is the first evidence that ectopic Laminin expression depends on Ecad loss and allows Ecad-dysfunctional cells to survive and invade. This opens new avenues for using LM-γ2 signalling regulators as molecular targets to impair gastric cancer progression.


Subject(s)
Cadherins/genetics , Gene Deletion , Laminin/genetics , Stomach Neoplasms/metabolism , Animals , Cell Line, Tumor , Drosophila , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Humans , Neoplasm Invasiveness , Stomach Neoplasms/pathology , Stomach Neoplasms/physiopathology , Up-Regulation
4.
Aliment. nutr ; 6(29): 41-4, 1986. ilus
Article in Portuguese | LILACS | ID: lil-38271

ABSTRACT

Salienta-se a importância da participaçäo do nutricionista na relaçäo saúde-doença dentro do real contexto social, econômico e político da populaçäo. Na rede de atençäo à saúde, o nutricionista atua nos três níveis de prevençäo, fazendo parte integrante da equipe multiprofissional. Na prevençäo primária, período pré-patogênico, atua na promoçäo da saúde orientando a alimentaçäo adequada aos diversos grupos, como também na proteçäo específica priorizando e orientando a distribuiçäo de suplementos alimentares. Competem ao nutricionista, integrante da equipe multiprofissional, a discussäo e implantaçäo de programas de nutriçäo dentro dos programas de prevençäo da saúde. Experiências nessa área vêm sendo desenvolvida na regiäo de Campinas/SP. Recomenda-se que as Secretarias Municipais de Saúde, Promoçäo Social e Educaçäo contratem este profissional para atuar nos diferentes níveis


Subject(s)
Primary Health Care
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