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1.
Int J Mol Sci ; 22(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925480

RESUMO

Conventional chemotherapy for acute myeloid leukemia regimens generally encompass an intensive induction phase, in order to achieve a morphological remission in terms of bone marrow blasts (<5%). The majority of cases are classified as Primary Induction Response (PIR); unfortunately, 15% of children do not achieve remission and are defined Primary Induction Failure (PIF). This study aims to characterize the gene expression profile of PIF in children with Acute Myeloid Leukemia (AML), in order to detect molecular pathways dysfunctions and identify potential biomarkers. Given that NUP98-rearrangements are enriched in PIF-AML patients, we investigated the association of NUP98-driven genes in primary chemoresistance. Therefore, 85 expression arrays, deposited on GEO database, and 358 RNAseq AML samples, from TARGET program, were analyzed for "Differentially Expressed Genes" (DEGs) between NUP98+ and NUP98-, identifying 110 highly confident NUP98/PIF-associated DEGs. We confirmed, by qRT-PCR, the overexpression of nine DEGs, selected on the bases of the diagnostic accuracy, in a local cohort of PIF patients: SPINK2, TMA7, SPCS2, CDCP1, CAPZA1, FGFR1OP2, MAN1A2, NT5C3A and SRP54. In conclusion, the integrated analysis of NUP98 mutational analysis and transcriptome profiles allowed the identification of novel putative biomarkers for the prediction of PIF in AML.


Assuntos
Biomarcadores Tumorais/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Quinase 6 Dependente de Ciclina/genética , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/genética , Humanos , Lactente , Recém-Nascido , Masculino , Família Multigênica , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Falha de Tratamento
2.
Biomedicines ; 9(5)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926064

RESUMO

Carnosine (ß-alanyl-L-histidine) is a naturally occurring endogenous peptide widely distributed in excitable tissues such as the brain. This dipeptide has well-known antioxidant, anti-inflammatory, and anti-aggregation activities, and it may be useful for treatment of neurodegenerative disorders such as Alzheimer's disease (AD). In this disease, peripheral infiltrating macrophages play a substantial role in the clearance of amyloid beta (Aß) peptides from the brain. Correspondingly, in patients suffering from AD, defects in the capacity of peripheral macrophages to engulf Aß have been reported. The effects of carnosine on macrophages and oxidative stress associated with AD are consequently of substantial interest for drug discovery in this field. In the present work, a model of stress induced by Aß1-42 oligomers was investigated using a combination of methods including trypan blue exclusion, microchip electrophoresis with laser-induced fluorescence, flow cytometry, fluorescence microscopy, and high-throughput quantitative real-time PCR. These assays were used to assess the ability of carnosine to protect macrophage cells, modulate oxidative stress, and profile the expression of genes related to inflammation and pro- and antioxidant systems. We found that pre-treatment of RAW 264.7 macrophages with carnosine counteracted cell death and apoptosis induced by Aß1-42 oligomers by decreasing oxidative stress as measured by levels of intracellular nitric oxide (NO)/reactive oxygen species (ROS) and production of peroxynitrite. This protective activity of carnosine was not mediated by modulation of the canonical inflammatory pathway but instead can be explained by the well-known antioxidant and free-radical scavenging activities of carnosine, enhanced macrophage phagocytic activity, and the rescue of fractalkine receptor CX3CR1. These new findings obtained with macrophages challenged with Aß1-42 oligomers, along with the well-known multimodal mechanism of action of carnosine in vitro and in vivo, substantiate the therapeutic potential of this dipeptide in the context of AD pathology.

3.
Optom Vis Sci ; 98(2): 159-169, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33534380

RESUMO

SIGNIFICANCE: Contact lens (CL) wearing may cause discomfort and eye dryness. We describe here the efficacy of a synthetic polymer in protecting both the corneal epithelial cells and the CL from desiccation damage. Artificial tears containing this polymer might be helpful to treat or prevent ocular surface damage in CL wearers. PURPOSE: We aimed to investigate the protective effects of the synthetic polymer 2-methacryloyloxyethyl phosphorylcholine (poly-MPC) on corneal epithelial cells and CLs subjected to desiccation damage. METHODS: The interaction of poly-MPC with the cell membrane was evaluated on human primary corneal epithelial cells (HCE-F) by the sodium dodecyl sulfate damage protection assay or the displacement of the cell-binding lectin concanavalin A (ConA). Survival in vitro of HCE-F cells and ex vivo of porcine corneas exposed to desiccating conditions after pre-treatment with poly-MPC or hyaluronic acid (HA), hypromellose (HPMC), and trehalose was evaluated by a colorimetric assay. Soft CLs were soaked overnight in a solution of poly-MPC/HPMC and then let dry in ambient air. Contact lens weight, morphology, and transparency were periodically registered until complete dryness. RESULTS: Polymer 2-methacryloyloxyethyl phosphorylcholine and HPMC were retained on the HCE-F cell membrane more than trehalose or HA. Polymer 2-methacryloyloxyethyl phosphorylcholine, HA, and HPMC either alone or in association protected corneal cells from desiccation significantly better than did trehalose alone or in association with HA. Contact lens permeation by poly-MPC/HPMC preserved better their shape and transparency than did saline. CONCLUSIONS: Polymer 2-methacryloyloxyethyl phosphorylcholine coats and protects corneal epithelial cells and CLs from desiccation damage more efficiently compared with trehalose and as good as other reference compounds.


Assuntos
Lentes de Contato Hidrofílicas , Dessecação , Epitélio Corneano/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Ácidos Polimetacrílicos/farmacologia , Falha de Prótese/efeitos dos fármacos , Animais , Células Cultivadas , Síndromes do Olho Seco/tratamento farmacológico , Humanos , Ácido Hialurônico/farmacologia , Derivados da Hipromelose/farmacologia , Fosforilcolina/farmacologia , Dodecilsulfato de Sódio/toxicidade , Suínos , Trealose/farmacologia
4.
J Clin Med ; 9(11)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126475

RESUMO

The pathophysiological mechanisms of venous thromboembolism are venous stasis, endothelial damage, and hypercoagulability, while less attention has been given to the role of both innate and native immunity. In this paper, we investigate the involvement of the activated immune system detected through some indicators such as TIM3 and Dectin-1 expressed by T lymphocytes. TIM3 and Dectin-1, two surface molecules that regulate the fine-tuning of innate and adaptive immune responses, were evaluated in patients affected by deep vein thrombosis of lower limbs (DVTLL). CD3+, CD4+ and CD8+ T lymphocytes obtained from patients affected by DVTLL were analysed using fluorescence-conjugated antibodies for TIM3 and Dectin-1 by an imaging flow cytometer. DVTLL patients showed a higher number of CD4+ and CD8+ T lymphocytes. TIM3 expression in T lymphocytes was very low in both DVTLL patients and controls. On the contrary, an increase in Dectin-1+ cells among CD4+ and CD8+ T lymphocytes from DVTLL patients was observed. Dectin-1 is known to play a role in inflammation and immunity and our result suggests its potential involvement in thrombotic venous disease.

5.
Int J Mol Sci ; 21(15)2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32727075

RESUMO

Brain and other nervous system cancers are the 10th leading cause of death worldwide. Genome instability, cell cycle deregulation, epigenetic mechanisms, cytoarchitecture disassembly, redox homeostasis as well as apoptosis are involved in carcinogenesis. A diet rich in fruits and vegetables is inversely related with the risk of developing cancer. Several studies report that cruciferous vegetables exhibited antiproliferative effects due to the multi-pharmacological functions of their secondary metabolites such as isothiocyanate sulforaphane deriving from the enzymatic hydrolysis of glucosinolates. We treated human astrocytoma 1321N1 cells for 24 h with different concentrations (0.5, 1.25 and 2.5% v/v) of sulforaphane plus active myrosinase (Rapha Myr®) aqueous extract (10 mg/mL). Cell viability, DNA fragmentation, PARP-1 and γH2AX expression were examined to evaluate genotoxic effects of the treatment. Cell cycle progression, p53 and p21 expression, apoptosis, cytoskeleton morphology and cell migration were also investigated. In addition, global DNA methylation, DNMT1 mRNA levels and nuclear/mitochondrial sirtuins were studied as epigenetic biomarkers. Rapha Myr® exhibited low antioxidant capability and exerted antiproliferative and genotoxic effects on 1321N1 cells by blocking the cell cycle, disarranging cytoskeleton structure and focal adhesions, decreasing the integrin α5 expression, renewing anoikis and modulating some important epigenetic pathways independently of the cellular p53 status. In addition, Rapha Myr® suppresses the expression of the oncogenic p53 mutant protein. These findings promote Rapha Myr® as a promising chemotherapeutic agent for integrated cancer therapy of human astrocytoma.


Assuntos
Anoikis/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Astrocitoma/metabolismo , Metilação de DNA/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Proteínas de Neoplasias/metabolismo , Sirtuínas/metabolismo , Astrocitoma/tratamento farmacológico , Astrocitoma/patologia , Linhagem Celular Tumoral , Glicosídeo Hidrolases/farmacologia , Humanos , Isotiocianatos/farmacologia , Sulfóxidos
6.
Cornea ; 39(11): 1419-1425, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32452988

RESUMO

PURPOSE: To isolate and characterize an epithelial cell (EC) line from a human donor cornea, which may serve as a reliable test cell line to address biomolecular issues and study the response of corneal epithelium to stressing events and therapeutic treatments. METHODS: A corneal button from a donor patient was treated with enzymes to separate the epithelial sheet and to free EC, which were put in tissue culture. ECs were characterized by optic and electronic microscopies, cytokeratins and PAX6 were detected by SDS-PAGE and western immunoblotting, the barrier function was evaluated by transepithelial electric resistance and by the immune detection of membrane junction proteins, and the karyotype was characterized according to the classical methods. RESULTS: Morphological analyses returned the picture of classical homogeneous polygonal morphology as expecetd by EC that was maintained over time and several in vitro passages. Transepithelial electric resistance values were characteristic of a typical barrier-forming cell line. The cytokeratin expression pattern was the one expected for corneal EC with a predominance of CK3 and CK5 and different from a human keratocyte cell line. The male karyotype showed 2 trisomies, of chromosomes 8 and 11. CONCLUSIONS: All the data so far obtained with the HCE-F cells concur to certify this cell line as a stable, true primary human corneal EC line, which could then be used as a test cell line to study and address the questions concerning the biological response of human corneal epithelium to stressing and/or therapeutic treatments and as a term of comparison for EC derived from pathological corneas.


Assuntos
Epitélio Corneano/citologia , Western Blotting , Linhagem Celular , Impedância Elétrica , Epitélio Corneano/fisiologia , Humanos , Doadores de Tecidos
7.
Biomedicines ; 8(4)2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32260532

RESUMO

 Background: The etiology and the mechanism behind atropine treatment of progressive myopia are still poorly understood. Our study addressed the role of scleral and choroidal fibroblasts in myopia development and atropine function. METHODS: Fibroblasts treated in vitro with atropine or 7-methylxanthine were tested for ECM production by Western blotting. Corneal epithelial cells were treated with atropine in the presence or absence of colostrum or fucosyl-lactose, and cell survival was evaluated by the MTT metabolic test. RESULTS: Atropine and 7-methyl-xanthine stimulated collagen I and fibronectin production in scleral fibroblasts, while they inhibited their production in choroidal fibroblasts. Four days of treatment with atropine of corneal epithelial cells significantly decreased cell viability, which could be prevented by the presence of colostrum or fucosyl-lactose. CONCLUSIONS: Our results show that atropine may function in different ways in different eye districts, strengthening the scleral ECM and increasing permeability in the choroid. The finding that colostrum or fucosyl-lactose attenuate the corneal epithelial toxicity after long-term atropine treatment suggests the possibility that both compounds can efficiently blunt its toxicity in children subjected to chronic atropine treatment.

8.
Molecules ; 25(3)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046220

RESUMO

Honokiol (2) is a natural bisphenol neolignan showing a variety of biological properties, including antitumor activity. Some studies pointed out 2 as a potential anticancer agent in view of its antiproliferative and pro-apoptotic activity towards tumor cells. As a further contribution to these studies, we report here the synthesis of a small library of bisphenol neolignans inspired by honokiol and the evaluation of their antiproliferative activity. The natural lead was hence subjected to simple chemical modifications to obtain the derivatives 3-9; further neolignans (12a-c, 13a-c, 14a-c, and 15a) were synthesized employing the Suzuki-Miyaura reaction, thus obtaining bisphenols with a substitution pattern different from honokiol. These compounds and the natural lead were subjected to antiproliferative assay towards HCT-116, HT-29, and PC3 tumor cell lines. Six of the neolignans show GI50 values lower than those of 2 towards all cell lines. Compounds 14a, 14c, and 15a are the most effective antiproliferative agents, with GI50 in the range of 3.6-19.1 µM, in some cases it is lower than those of the anticancer drug 5-fluorouracil. Flow cytometry experiments performed on these neolignans showed that the inhibition of proliferation is mainly due to an apoptotic process. These results indicate that the structural modification of honokiol may open the way to obtaining antitumor neolignans more potent than the natural lead.


Assuntos
Compostos Benzidrílicos/síntese química , Compostos Benzidrílicos/farmacologia , Compostos de Bifenilo/química , Proliferação de Células/efeitos dos fármacos , Lignanas/síntese química , Lignanas/farmacologia , Fenóis/síntese química , Fenóis/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células HCT116 , Células HT29 , Humanos , Lignanas/química , Células PC-3
9.
Int J Mol Sci ; 20(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652751

RESUMO

The awareness of genome complexity brought a radical approach to the study of transcriptome, opening eyes to single RNAs generated from two or more adjacent genes according to the present consensus. This kind of transcript was thought to originate only from chromosomal rearrangements, but the discovery of readthrough transcription opens the doors to a new world of fusion RNAs. In the last years many possible intergenic cis-splicing mechanisms have been proposed, unveiling the origins of transcripts that contain some exons of both the upstream and downstream genes. In some cases, alternative mechanisms, such as trans-splicing and transcriptional slippage, have been proposed. Five databases, containing validated and predicted Fusion Transcripts of Adjacent Genes (FuTAGs), are available for the scientific community. A comparative analysis revealed that two of them contain the majority of the results. A complete analysis of the more widely characterized FuTAGs is provided in this review, including their expression pattern in normal tissues and in cancer. Gene structure, intergenic splicing patterns and exon junction sequences have been determined and here reported for well-characterized FuTAGs. The available functional data and the possible roles in cancer progression are discussed.


Assuntos
Neoplasias/genética , Trans-Splicing , Regulação Neoplásica da Expressão Gênica , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
BMC Cancer ; 18(1): 1265, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563495

RESUMO

BACKGROUND: Broad copy number aberrations (BCNAs) represent a common form of genome instability in colorectal cancer (CRC). CRCs show large variations in their level of aneuploidy: microsatellite-instable (MSI) tumors are known to have a near-diploid karyotype while microsatellite-stable (MSS) tumors show high level of chromosomal instability. However, MSS tumors have great heterogeneity in the number of BCNAs, with a minor percentage of samples showing an almost normal karyotype. In the present work we subdivided MSS CRCs according to a "BCNA score" and characterized their transcriptome profiles, considered as a proxy to their phenotypic features. METHODS: Microsatellite testing, genome-wide DNA copy number and whole-transcript expression analysis (HTA) were performed on 33 tumor samples and 25 normal colonic tissue samples from 32 CRC patients. 15.1% of the samples were MSI tumors (n = 5), whereas 84.9% were MSS tumors (n = 28). Gene expression data of 34 additional MSI tumors was retrieved from a public functional genomics data repository. RESULTS: Using as a threshold the first quartile of the BCNA score distribution, MSS samples were classified as low-BCNA (LB, n = 7) or high-BCNA (HB, n = 21). LB tumors were enriched for mucinous CRCs and their gene-expression profile resembled that of MSI samples for what concerns a subset of genes involved in secretory processes, mucosal protection, and extracellular matrix remodeling. HB tumors were predominantly non-mucinous adenocarcinomas and showed overexpression of a subset of genes typical of surface colonocytes and EGF signaling. A large percentage of unclassified samples according to the consensus molecular subtypes (CMS) classifier was found in the LB group (43%), whereas 76% HB tumors belonged to CMS2. CONCLUSIONS: A classification of colorectal tumors based on the number of BCNAs identifies two groups of MSS tumors which differ for histopathology and gene expression profile. Such information can be exploited for its translational relevance in different aspects of CRC clinical management.


Assuntos
Neoplasias Colorretais/genética , Variações do Número de Cópias de DNA/genética , Instabilidade Genômica/genética , Transcriptoma/genética , Idoso , Instabilidade Cromossômica/genética , Colo , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade
11.
Sci Rep ; 8(1): 14826, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287863

RESUMO

We re-examined the correlation between Broad Genomic Aberrations (BGAs) and transcriptomic profiles in Colorectal Cancer (CRC). Two types of BGAs have been examined: Broad Copy-Number Abnormal regions (BCNAs), distinguished in gain- and loss-type, and Copy-Neutral Loss of Heterozygosities (CNLOHs). Transcripts are classified as "OverT" or "UnderT" if overexpressed or underexpressed comparing CRCs bearing a specific BGA to CRCs not bearing it and as "UpT" or "DownT" if upregulated or downregulated in cancer compared to normal tissue. BGA-associated effects were evaluated by changes in the "Chromosomal Distribution Index" (CDI) of different transcript classes. Data show that UpT are more sensitive than DownT to BCNA-associated gene dosage effects. "Over-UpT" genes are upregulated in cancer and further overexpressed by gene dosage, defining the so called "positive caricature transcriptomic effect". When Over-UpT genes are ranked according to overexpression, top positions are occupied by genes implicated at the functional and therapeutic level in CRC. We show that cancer-upregulated transcripts are sensitive markers of BCNA-induced effects and suggest that analysis of positive caricature transcriptomic effects can provide clues toward the identification of BCNA-associated cancer driver genes.


Assuntos
Neoplasias Colorretais/genética , Variações do Número de Cópias de DNA/genética , Genoma Humano , Perda de Heterozigosidade/genética , Transcriptoma/genética , Cromossomos Humanos/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
J Cell Biochem ; 119(12): 9707-9719, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30129075

RESUMO

Zinc is a transition metal and catalytic cofactor involved in many biological processes including proliferation, development, differentiation, and metabolism. Zinc transporters (ZnTs) play a fundamental role in cellular zinc homeostasis. ZnTs are responsible of zinc efflux and are encoded by 10 genes belonging to solute carrier family 30A (SLC30A1-10), while zinc-regulated transporter (ZRT)/iron-regulated transporter (IRT)-like protein (ZIP) transporters are responsible for the influx of zinc into the cytoplasm and are encoded by 14 genes belonging to solute carrier family 39A (SLC39A1-14). In this study, we analyzed, by transcriptome analysis, the microRNA levels of ZnT-encoding and ZIP-encoding genes in colorectal cancer (CRC) samples matched to normal colon tissues and in CRC cell lines. Results revealed an upregulation of specific ZnT and ZIP transcripts in CRC. Upregulation of SLC30A5, SLC30A6, SLC30A7 transcripts, encoding zinc efflux transporters ZnT5, ZnT6, ZnT7, localized on endoplasmic reticulum membranes, might be part of a coordinated transcriptional program associated to the increased activity of the early secretory pathway, while transcriptional upregulation of several specific ZIP transporters (SLC39A6, SLC39A7, SLC39A9, SLC39A10, and SLC39A11) could contribute in meeting the increased demand of zinc in cancer cells. Moreover, exon-level analysis of SLC30A9, a nuclear receptor coactivator involved in the transcriptional regulation of Wnt-responsive genes, revealed the differential expression of alternative transcripts in CRC and normal colonic mucosa.


Assuntos
Proteínas de Transporte de Cátions/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Idoso , Neoplasias da Mama/genética , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Ciclina D1/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição , Via de Sinalização Wnt/genética , Zinco/metabolismo
13.
FEBS Open Bio ; 6(8): 794-806, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27516958

RESUMO

Copper homeostasis and distribution is strictly regulated by a network of transporters and intracellular chaperones encoded by a group of genes collectively known as copper homeostasis genes (CHGs). In this work, analysis of The Cancer Genome Atlas database for somatic point mutations in colorectal cancer revealed that inactivating mutations are absent or extremely rare in CHGs. Using oligonucleotide microarrays, we found a strong increase in mRNA levels of the membrane copper transporter 1 protein [CTR1; encoded by the solute carrier family 31 member 1 gene (SLC31A1 gene)] in our series of colorectal carcinoma samples. CTR1 is the main copper influx transporter and changes in its expression are able to induce modifications of cellular copper accumulation. The increased SLC31A1 mRNA level is accompanied by a parallel increase in transcript levels for copper efflux pump ATP7A, copper metabolism Murr1 domain containing 1 (COMMD1), the cytochrome C oxidase assembly factors [synthesis of cytochrome c oxidase 1 (SCO1) and cytochrome c oxidase copper chaperone 11 (COX11)], the cupric reductase six transmembrane epithelial antigen of the prostate (STEAP3), and the metal-regulatory transcription factors (MTF1, MTF2) and specificity protein 1 (SP1). The significant correlation between SLC31A1,SCO1, and COX11 mRNA levels suggests that this transcriptional upregulation might be part of a coordinated program of gene regulation. Transcript-level upregulation of SLC31A1,SCO1, and COX11 was also confirmed by the analysis of different colon carcinoma cell lines (Caco-2, HT116, HT29) and cancer cell lines of different tissue origin (MCF7, PC3). Finally, exon-level expression analysis of SLC31A1 reveals differential expression of alternative transcripts in colorectal cancer and normal colonic mucosa.

14.
J Inorg Biochem ; 156: 145-52, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26784148

RESUMO

Copper is a catalytic cofactor required for the normal function of many enzymes involved in fundamental biological processes but highly cytotoxic when in excess. Therefore its homeostasis and distribution is strictly regulated by a network of transporters and intracellular chaperones. ATOX1 (antioxidant protein 1) is a copper chaperone that plays a role in copper homeostasis by binding and transporting cytosolic copper to ATPase proteins in the trans-Golgi network. In the present study the Caco-2 cell line, a colon carcinoma cell line, was used as an in vitro model to evaluate if ATOX1 deficiency could affect sensitivity to experimentally induced copper dyshomeostasis. Silencing of ATOX1 increased toxicity of a short treatment with a high concentration of Cu(2+). Copper ionophores, such as 5-chloro-8-hydroxyquinoline, induced a copper-dependent cell toxicity which was significantly potentiated after ATOX1 silencing. The copper chelator TPEN (N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine) produced a form of cell toxicity that was reversed by the addition of Cu(2+). ATOX1 silencing increased Caco-2 cell sensitivity to TPEN toxicity. Our results suggest the possibility of a therapy with copper-chelating or ionophore drugs in subtypes of tumors showing specific alterations in ATOX1 expression.


Assuntos
Antineoplásicos/uso terapêutico , Inativação Gênica , Metalochaperonas/genética , Antineoplásicos/química , Células CACO-2 , Linhagem Celular Tumoral , Quelantes/química , Cobre/química , Proteínas de Transporte de Cobre , Humanos , Chaperonas Moleculares , RNA Mensageiro/genética
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