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1.
Molecules ; 28(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37836749

RESUMO

The aim of this study was to evaluate, for the first time, the antiproliferative, apoptotic and diminishing effects of the anchored growth-independent capacity of an ethanol macerate extract from the Annona cherimola seed (EMCHS) in the human gastric cancer cell line SNU-1. The cells treated with EMCHS (20 µg/mL) significantly reduced the capacity to form clones of the tumor cell. Moreover, 50 µg/mL of EMCHS extract induced apoptosis, as was shown by the Annexin-V assay. UHPLC-MS/MS analysis detected two acetogenins (Annonacinone and Annonacin) in the EMCHS, which could be largely responsible for its selective antiproliferative effect. The identification of fatty acids by GC-FID showed the presence of eight fatty acids, among which was, oleic acid, which has recognized activity as an adjuvant in antitumor treatments. Taken together, our results indicate that the EMCHS seems promising for use as a natural therapy against gastric cancer disease.


Assuntos
Annona , Carcinoma , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Espectrometria de Massas em Tandem , Extratos Vegetais/farmacologia , Linhagem Celular , Apoptose , Sementes , Acetogeninas/farmacologia , Ácidos Graxos/farmacologia , Linhagem Celular Tumoral
2.
Hepatology ; 73(5): 1783-1796, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32893372

RESUMO

BACKGROUND AND AIMS: Gallbladder cancer (GBC) is a neglected disease with substantial geographical variability: Chile shows the highest incidence worldwide, while GBC is relatively rare in Europe. Here, we investigate the causal effects of risk factors considered in current GBC prevention programs as well as C-reactive protein (CRP) level as a marker of chronic inflammation. APPROACH AND RESULTS: We applied two-sample Mendelian randomization (MR) using publicly available data and our own data from a retrospective Chilean and a prospective European study. Causality was assessed by inverse variance weighted (IVW), MR-Egger regression, and weighted median estimates complemented with sensitivity analyses on potential heterogeneity and pleiotropy, two-step MR, and mediation analysis. We found evidence for a causal effect of gallstone disease on GBC risk in Chileans (P = 9 × 10-5 ) and Europeans (P = 9 × 10-5 ). A genetically elevated body mass index (BMI) increased GBC risk in Chileans (P = 0.03), while higher CRP concentrations increased GBC risk in Europeans (P = 4.1 × 10-6 ). European results suggest causal effects of BMI on gallstone disease (P = 0.008); public Chilean data were not, however, available to enable assessment of the mediation effects among causal GBC risk factors. CONCLUSIONS: Two risk factors considered in the current Chilean program for GBC prevention are causally linked to GBC risk: gallstones and BMI. For Europeans, BMI showed a causal effect on gallstone risk, which was itself causally linked to GBC risk.


Assuntos
Índice de Massa Corporal , Proteína C-Reativa/análise , Neoplasias da Vesícula Biliar/etiologia , Cálculos Biliares/complicações , Adulto , Fatores Etários , Chile/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Neoplasias da Vesícula Biliar/epidemiologia , Neoplasias da Vesícula Biliar/genética , Cálculos Biliares/epidemiologia , Predisposição Genética para Doença/genética , Variação Genética , Humanos , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
3.
Plant Foods Hum Nutr ; 74(3): 322-327, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31154569

RESUMO

Annona cherimola is a tree belonging to the family Annonacea, whose fruit (cherimoya) is very desirable, but its seeds are considered waste. Present in these seeds are compounds that have been described as selective antiproliferative agents for cancer cells. The aim of this study was to evaluate the antiproliferative activity of ethanol macerate extract (EMCHS) obtained from A. cherimola seeds against the human stomach gastric adenocarcinoma (AGS) cell line and the normal human gastric epithelial cell line (GES-1). The EMCHS extract presented an IC50 of 80.43 µg/mL in AGS cells, and a selectivity index (SI) of 3.5-fold higher than that of cisplatin. In addition, the EMCHS extract showed apoptotic activity in AGS cells since 50 µg/mL. Overxpression of PUMA gene in both cells demonstrate that EMCHS activate the apoptotic route. Future studies should be carried out to elucidate anticancer activity of EMCHS in vivo. This work represents the first showing antiproliferative effects of crude extracts obtained from seeds of A. cherimola in AGS cells.


Assuntos
Adenocarcinoma/tratamento farmacológico , Annona/química , Apoptose/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sementes/química , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Etanol , Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas/genética , Estômago/patologia
4.
Pol J Microbiol ; 67(1): 11-18, 2018 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-30015420

RESUMO

The aim of this study was to develop a non-invasive diagnostic test for the detection of Helicobacter pylori in stool samples from digestive symptomatic patients, using a new protocol of nested-qPCR. A total of 143 patients were invited to participate in the study. A gastric biopsy of each patient was collected for Rapid Urease Testing (RUT) and histology by Giemsa stain. A fecal sample for nested-qPCR analysis was also obtained. DNA was extracted from the fecal samples, and conventional PCR followed by qPCR of the ureC gene of H. pylori was carried out. We evaluated the presence of H. pylori, in 103 females and 40 males, mean (± SD) age of 56.5 ± 14.18. The sensitivity of RUT to detect the infection was 67.0% (95% C.I.: 57.2 - 75.8) and specificity was 92.3% (95% C.I.: 76.5 - 99.1). Histology by Giemsa stain, commonly used as a reference for H. pylori detection, showed a sensitivity of 98.6% (95% C.I.: 92.5 - 100.0) and a specificity of 89.7% (95% C.I.: 72.7 - 97.8). In contrast, detection of H. pylori infection in stools by nested-qPCR showed a sensitivity of 100% (95% C.I.: 94.9 - 100.0) and a specificity of 83.9% (95% C.I.: 66.3 - 94.6). Our test, based in nested-qPCR is a better diagnostic alternative than conventional RUT, and is similar to histology by Giemsa stain in the detection of H. pylori, by which the test could be used for non-invasive diagnosis in clinical practice.


Assuntos
Proteínas de Bactérias/genética , Fezes/microbiologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Adulto , Idoso , Feminino , Helicobacter pylori/genética , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
5.
Rev Med Chil ; 146(5): 596-602, 2018 May.
Artigo em Espanhol | MEDLINE | ID: mdl-30148923

RESUMO

BACKGROUND: Helicobacter pylori is the most significant pathogen associated with gastric diseases, including gastric cancer. Infected patients with strains that are CagA-positive generally have worse outcomes than those infected with CagA-negative strains. Patients infected with CagA-positive strains have a higher risk for developing gastric cancer. AIM: To determine the prevalence of CagA-positive H. pylori strains in fecal samples of patients from the Coquimbo Region of Chile, using a non-invasive, nested-qPCR method. MATERIAL AND METHODS: We evaluated 160 patients with gastrointestinal symptoms subjected to an upper gastrointestinal endoscopy. DNA was extracted from fecal samples and tested for the presence of H. pylori using nested-qPCR for the ureC gene, and subsequently compared with the results of histology-Giemsa stain from the patients' endoscopic biopsies. When H. pylori was found, the presence of CagA-positive strains was determined via nested-qPCR. RESULTS: The histology-Giemsa stain was positive for H. pylori infection in 123 patients (76.9%), while the analysis of fecal samples detected H. pylori in 129 patients (80.6%). The sensitivity and specificity of nested-qPCR to detect the bacterium was 96.7 and 73.0% respectively. Among patients with the infection, 25% had CagA-positive strains. CONCLUSIONS: In this sample of patients, there is a low prevalence of CagA-positive H. pylori strains.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , DNA Bacteriano/análise , Fezes/microbiologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/genética , Gastropatias/microbiologia , Antígenos de Bactérias/isolamento & purificação , Proteínas de Bactérias/isolamento & purificação , Endoscopia do Sistema Digestório , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Gastropatias/diagnóstico
6.
Foods ; 13(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38540820

RESUMO

The aim of this work is to describe the effect of convective drying (CD), vacuum drying (VD), infrared drying (IRD), low-temperature vacuum drying (LTVD) and freeze drying (FD) on bio-compound retention of red cabbage and its beneficial health properties. The total phenolics content (TPC), flavonoids (TFC), anthocyanin (TAC) and glucosinolates (TGC) were determined by spectrophotometry. The profiles of phenolic acids, amino acids and fatty acids were determined by HPLC-UV-DAD, LC-DAD and GC-FID, respectively. Antioxidant potential was verified by DPPH and ORAC assays. The antiproliferative activity was measured in the human gastric cell line (AGS). Anti-inflammatory activity was evaluated by phorbol 12-myristate 13-acetate and arachidonic acid models. VD showed high values of TPC = 11.89 ± 0.28 mg GAE/g d.m.; TFC = 11.30 ± 0.9 mg QE/g d.m.; TAC = 0.265 ± 0.01 mg Cya3glu/g d.m.; and TGC = 51.15 ± 3.31 µmol SE/g d.m. Caffeic acid, ferulic acid and sinapic acid were identified. The predominant amino acid and fatty acid were glutamic acid and γ-linolenic acid, respectively. The antioxidant potential was dependent on drying methods for both DPPH and ORAC assays. Dried red cabbage extracts showed clear anti-inflammatory and antiproliferative activity. The dehydration process is an alternative for the retention of bio-compounds and health-promoting properties of red cabbage.

7.
Nat Prod Res ; 36(17): 4482-4486, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34587849

RESUMO

The objective of the present study was to investigate the antioxidant and antiproliferative effects of lemon extracts (LE) against human gastric cancer cells (SNU-1) and normal human gastric epithelial cells (GES-1), and their mechanism of inducing cellular death. LE was obtained by three extraction methods: conventional (CE), ultrasound (UAE) and high hydrostatic pressure (HHPE). Experimental results show that the extraction method used to obtain the LE had a significant influence on antioxidant capacity, cellular proliferation, and induction of apoptosis in SNU-1 cells. LE was showed to be cytotoxic with an IC50 of 1747.0 µg mL-1 and 1704.3 µg mL-1, as obtained by UAE and HHPE, respectively. In addition, this extract induces apoptosis as evidenced by confocal microscopy. Our findings indicate that LE would be an attractive source of bioactive compounds with antioxidant and antiproliferative capacity and can improve the functional value of food.


Assuntos
Antioxidantes , Neoplasias Gástricas , Antioxidantes/farmacologia , Apoptose , Humanos , Pressão Hidrostática , Extratos Vegetais/farmacologia , Neoplasias Gástricas/tratamento farmacológico
8.
Eur J Pharmacol ; 896: 173910, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33508285

RESUMO

Despite current achievements and innovations in cancer treatment, conventional chemotherapy has several limitations, such as unsatisfactory long-term survival, cancer drug resistance and toxicity against non-tumoral cells. In the search for safer therapeutic alternatives, docosahexaenoic acid (DHA) has shown promising effects inhibiting tumor growth without significant side effects in several types of cancer, but in gastric cancer (GC) its effects have not been completely described. In this study, we characterized the effects of DHA in GC using in vivo and in vitro models. Among all of the evaluated Ω-3 and Ω-6 fatty acids, DHA showed the highest antiproliferative potency and selectivity against the GC-derived cell line AGS. 10-100 µM DHA decreased AGS cell viability in a concentration-dependent manner but had no effect on non-tumoral GES-1 cells. To evaluate if the effects of DHA were due to apoptosis induction, cells were stained with Annexin V-PI, observing that 75 and 100 µM DHA increased apoptosis in AGS, but not in GES-1 cells. Additionally, levels of several proapoptotic and antiapoptotic regulators were assessed by qPCR, western blot and activity assays, showing similar results. In order to evaluate DHA efficacy in vivo, xenografts in an immunodeficient mouse model (BALB/cNOD-SCID) were used. In these experiments, DHA treatment for six weeks consistently reduced subcutaneous tumor size, ascitic fluid volume and liver metastasis. In summary, we found that DHA has a selective antiproliferative effect on GC, being this effect driven by apoptosis induction. Our investigation provides promising features for DHA as potential therapeutic agent in GC.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos SCID , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Mol Diagn ; 23(9): 1127-1137, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34186175

RESUMO

About 4% to 7% of the non-small-cell lung cancer patients have anaplastic lymphoma kinase (ALK) rearrangements, and specific targeted therapies improve patients' outcomes significantly. ALK gene fusions are detected by immunohistochemistry or fluorescent in situ hybridization as gold standards in South America. Next-generation sequencing-based assays are a reliable alternative, able to perform simultaneous detection of multiple events from a single sample. We analyzed 4240 non-small-cell lung cancer samples collected in 37 hospitals from Chile, Brazil, and Peru, where ALK rearrangements were determined as part of their standard of care (SofC) using either immunohistochemistry or fluorescent in situ hybridization. A subset of 1450 samples was sequenced with the Oncomine Focus Assay (OFA), and the concordance with the SofC tests was measured. An orthogonal analysis was performed using a real-time quantitative PCR echinoderm microtubule-associated protein-like 4-ALK fusion detection kit. ALK fusion prevalence is similar for Chile (3.67%; N = 2142), Brazil (4.05%; N = 1013), and Peru (4.59%; N = 675). Although a comparison between OFA and SofC assays showed similar sensitivity, OFA had significantly higher specificity and higher positive predictive value, which opens new opportunities for a more specific determination of ALK gene rearrangements.


Assuntos
Quinase do Linfoma Anaplásico/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Fusão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Proteínas de Fusão Oncogênica/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Chile/epidemiologia , Feminino , Rearranjo Gênico , Humanos , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente/métodos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Padrão de Cuidado , Adulto Jovem
10.
J Gastrointest Cancer ; 51(2): 571-578, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31407248

RESUMO

PURPOSE: In this work, we present a recently developed ruthenium complex that shows anticancer activity in gallbladder cancer cells. METHODS: After the synthesis of the new ruthenium complexes, the antiproliferative, cytotoxicity, and apoptosis activities were evaluated in vitro by the triple assay ApoTox-Glo. Then, the transcription levels of genes related to apoptosis were evaluated by real-time PCR (q-PCR). RESULTS: The ruthenium complex, called Ru-UCN3, inhibits the proliferation of gallbladder cancer cells G-415 by means of apoptosis, which was demonstrated by the overexpression of the pro-apoptotic genes Puma, Diablo, and Caspasa-9 together with the repression of the anti-apoptotic genes Bcl-xL and Bcl-2. In addition, we found strong caspase 3/7 activity in the cells at 24 h of the Ru-UCN3 exposure, which was evaluated by the triple ApoTox-Glo assay. CONCLUSION: The new ruthenium complexes evaluated had an inhibitory effect on G-415 cells. We think that Ru-UCN3 could be a promising anticancer agent, which should be explored with more in vitro and in vivo assays and probably with the chemical modulation of this molecule.


Assuntos
Morte Celular/efeitos dos fármacos , Neoplasias da Vesícula Biliar/tratamento farmacológico , Rutênio/química , Linhagem Celular Tumoral , Proliferação de Células , Humanos
11.
Sci Rep ; 10(1): 10534, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601436

RESUMO

The cytotoxic mechanism of the saponin QS-21 and its aglycone quillaic acid (QA) was studied on human gastric cancer cells (SNU1 and KATO III). Both compounds showed in vitro cytotoxic activity with IC50 values: 7.1 µM (QS-21) and 13.6 µM (QA) on SNU1 cells; 7.4 µM (QS-21) and 67 µM (QA) on KATO III cells. QS-21 and QA induce apoptosis on SNU1 and KATO III, as demonstrated by TUNEL, Annexin-V and Caspase Assays. Additionally, we performed in silico docking studies simulating the binding of both triterpenic compounds to key proteins involved in apoptotic pathways. The binding energies (∆Gbin) thus calculated, suggest that the pro-apoptotic protein Bid might be a plausible target involved in the apoptotic effect of both triterpenic compounds. Although QA shows some antiproliferative effects on SNU1 cells cultured in vitro, our results suggest that QS-21 is a more powerful antitumor agent, which merits further investigation regarding their properties as potential therapeutic agents for gastric cancer.


Assuntos
Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ácido Oleanólico/análogos & derivados , Quillaja , Saponinas/química , Neoplasias Gástricas/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Ácido Oleanólico/uso terapêutico , Saponinas/farmacologia , Saponinas/uso terapêutico
12.
Cancer Epidemiol ; 65: 101643, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058310

RESUMO

BACKGROUND: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. METHODS: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. RESULTS: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. CONCLUSION: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Neoplasias da Vesícula Biliar/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Chile/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Neoplasias da Vesícula Biliar/epidemiologia , Estudos de Associação Genética , Humanos , Indígenas Sul-Americanos/genética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , População Branca/genética
13.
J Gastrointest Cancer ; 50(1): 175-180, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30632030

RESUMO

PURPOSE: Music has recognized beneficial effects on cancer patients; however, very little is known about the molecular processes which produce these benefits. The aim of this work was to evaluate the effect of music on proliferation and gene expression in gastric cancer cells. METHODS: AGS gastric cancer cells were exposed to metal and classical music, and subsequently cell proliferation and expression of genes associated with apoptosis and cell-cycle control were evaluated. RESULTS: Proliferation of AGS cells increased when exposed to metal music, but not when exposed to classical music. Gene expression of caspase-3 and 8 and cyclin B1 increased in response to both musical genres; classical music repressed the expression of p53, and metal music repressed the expression of PUMA. CONCLUSIONS: This is the first study to demonstrate music as a modulator of gene expression in a cancer cell line. Additional experiments are required to better understand the mechanisms of how different musical genres can induce changes in gene expression.


Assuntos
Música/psicologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Gástricas/patologia
14.
Life Sci ; 217: 193-201, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30528721

RESUMO

AIMS: Ruthenium-based compounds exhibit critical biochemical properties making them suitable for diverse pharmacological applications. The aim of this work was to study the anticancer effects of three ruthenium complexes on a human gastric cancer cell line. MAIN METHODS: We synthetized three [Ru(η6-anethole)(en)X]PF6 complexes, where (en) is ethylenediamine and X is Cl (1), Br (2) or I (3), which were then evaluated by MTT assay, RT-qPCR and flow cytometry on the human gastric cancer cell line AGS. KEY FINDINGS: Compound 3 exhibited the highest cytotoxicity (IC50 = 11.27 ±â€¯1.08 µM) of the series, with an activity almost three-fold more potent than the commercial drug cisplatin, and also revealed a 4.5-fold less potent cytotoxicity in the human normal gastric cell line GES-1. The exchange of the halogen (Cl, Br or I) on the organometallic compound slightly alters its solubility in PBS and lipophilicity (expressed as Log P). Studies of gene expression revealed that compound 3 induces a significant overexpression of the pro-apoptotic genes Caspase-3, PUMA and DIABLO in the gastric cancer cell line AGS after 6 h. In contrast, only PUMA was significantly overexpressed in the normal gastric cell line GES-1. Compound 3 induced the activation of multiple caspases in AGS cells: a sign of apoptosis. Characterization via single-crystal X-ray diffraction for compound 3 confirmed the key structural features for this type of organometallic complexes. SIGNIFICANCE: Our data suggests that compound 3 may be an interesting anticancer molecule for the treatment of gastric cancer.


Assuntos
Anisóis/química , Anisóis/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Rutênio/química , Rutênio/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Derivados de Alilbenzenos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Humanos , Modelos Moleculares , Solubilidade , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Água/química
15.
Front Pharmacol ; 10: 612, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249523

RESUMO

Gastric cancer (GC) is the one of the most prevalent cancers and one of the leading causes of cancer-induced deaths. Previously, we found that the expression of purinergic P2Y2 receptor (P2Y2R) is increased in GC samples as compared to adjacent healthy mucosa taken from GC-diagnosed patients. In this work, we studied in detail purinergic signaling in the gastric adenocarcinoma-derived cell lines: AGS, MKN-45, and MKN-74, and compared them to a nontumoral epithelial cell line: GES-1. In GC-derived cells, we detected the expression of several purinergic receptors, and found important differences as compared to GES-1 cells. Functional studies revealed a strong contribution of P2Y2Rs in intracellular calcium increases, elicited by adenosine-triphosphate (ATP), uridine-triphosphate (UTP), and the P2Y2R agonist MRS2768. Responses were preserved in the absence of extracellular calcium and inhibited by P2Y2R antagonists. In GES-1 cells, ATP and UTP induced similar responses and the combination of P2X and P2Y receptor antagonists was able to block them. Proliferation studies showed that ATP regulates AGS and MKN-74 cells in a biphasic manner, increasing cell proliferation at 10-100 µM, but inhibiting at 300 µM ATP. On the other hand, 1-300 µM UTP, a P2Y2R agonist, increased concentration-dependent cell proliferation. The effects of UTP and ATP were prevented by both wide-range and specific purinergic antagonists. In contrast, in GES-1 cells ATP only decreased cell proliferation in a concentration-dependent manner, and UTP had no effect. Notably, the isolated application of purinergic antagonists was sufficient to change the basal proliferation of AGS cells, indicating that nucleotides released by the cells can act as paracrine/autocrine signals. Finally, in tumor-derived biopsies, we found an increase of P2Y2R and a decrease in P2X4R expression; however, we found high variability between seven different biopsies and their respective adjacent healthy gastric mucosa. Even so, we found a correlation between the expression levels of P2Y2R and P2X4R and survival rates of GC patients. Taken together, these results demonstrate the involvement of different purinergic receptors and signaling in GC, and the pattern of expression changes in tumoral cells, and this change likely directs ATP and nucleotide signaling from antiproliferative effects in healthy tissues to proliferative effects in cancer.

16.
World J Gastrointest Oncol ; 9(2): 62-69, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28255427

RESUMO

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world and the fourth principal cause of cancer deaths worldwide. Currently, there is a lack of low cost and noninvasive screening tests for CRC, becoming a serious health problem. In this context, a potential biomarker for the early detection of CRC has recently gained attention. Circular RNAs (circRNA), a re-discovered, abundant RNA specie, is a type of noncoding covalent closed RNAs formed from both exonic and intronic sequences. These circular molecules are widely expressed in cells, exceeding the abundance of the traditional linear mRNA transcript. They can regulate gene expression, acting as real sponges for miRNAs and also regulate alternative splicing or act as transcriptional factors and inclusive encoding for proteins. However, little is known about circRNA and its relationship with CRC. In this review, we focus on the biogenesis, function and role of these circRNAs in relation to CRC, including their potential as a new biomarker.

17.
Asian Pac J Cancer Prev ; 15(5): 1931-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24716914

RESUMO

BACKGROUND: Gastric cancer (GC) ranks as one of the major causes of mortality due to cancer worldwide. In Chile, it is currently the leading cause of cancer death. Identification of novel molecular markers that may help to improve disease diagnosis at early stages is imperative. MATERIALS AND METHODS: Using whole-genome DNA microarrays we determined differential mRNA levels in fresh human GC samples compared to adjacent healthy mucosa from the same patients. Genes significantly overexpressed in GC were validated by RT-PCR in a group of 14 GC cases. RESULTS: The genes CD248, NSD1, RAB17, ABCG8, Ephb1 and P2RY2 were detected as the top overexpressed in GC biopsies. P2RY2, Ephb1 and CD248 showed the best sensitivity for GC detection with values of 92.9%, 85.7% and 64.3% (p<0.05), respectively. Specificity was 85.7%, 71.4% and 71.4% (p<0.05), for each respectively.


Assuntos
Antígenos CD/genética , Antígenos de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica/genética , Receptor EphB1/genética , Receptores Purinérgicos P2Y2/genética , Neoplasias Gástricas/genética , Biomarcadores Tumorais , Chile , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Mensageiro/genética
18.
Rev. méd. Chile ; 146(5): 596-602, mayo 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-961436

RESUMO

Background: Helicobacter pylori is the most significant pathogen associated with gastric diseases, including gastric cancer. Infected patients with strains that are CagA-positive generally have worse outcomes than those infected with CagA-negative strains. Patients infected with CagA-positive strains have a higher risk for developing gastric cancer. Aim: To determine the prevalence of CagA-positive H. pylori strains in fecal samples of patients from the Coquimbo Region of Chile, using a non-invasive, nested-qPCR method. Material and Methods: We evaluated 160 patients with gastrointestinal symptoms subjected to an upper gastrointestinal endoscopy. DNA was extracted from fecal samples and tested for the presence of H. pylori using nested-qPCR for the ureC gene, and subsequently compared with the results of histology-Giemsa stain from the patients' endoscopic biopsies. When H. pylori was found, the presence of CagA-positive strains was determined via nested-qPCR. Results: The histology-Giemsa stain was positive for H. pylori infection in 123 patients (76.9%), while the analysis of fecal samples detected H. pylori in 129 patients (80.6%). The sensitivity and specificity of nested-qPCR to detect the bacterium was 96.7 and 73.0% respectively. Among patients with the infection, 25% had CagA-positive strains. Conclusions: In this sample of patients, there is a low prevalence of CagA-positive H. pylori strains.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Gastropatias/microbiologia , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Helicobacter pylori/genética , Infecções por Helicobacter/diagnóstico , Fezes/microbiologia , Antígenos de Bactérias/genética , Gastropatias/diagnóstico , Proteínas de Bactérias/isolamento & purificação , Reação em Cadeia da Polimerase , Endoscopia do Sistema Digestório , Sensibilidade e Especificidade , Antígenos de Bactérias/isolamento & purificação
19.
Int J Biol Markers ; 27(2): e82-9, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22427189

RESUMO

Colorectal cancer is one of the most common forms of cancer worldwide. Early detection would allow patients to be treated surgically and halt the progression of the disease; however, the current methods of early detection are invasive (colonoscopy and sigmoidoscopy) or have low sensitivity (fecal occult blood test). The altered expression of genes in stool samples of patients with colorectal cancer can be determined by RT-PCR. This is a noninvasive and highly sensitive technique for colorectal cancer screening. According to information gathered in this review and our own experience, the use of fecal RNA to determine early alterations in gene expression due to malignancy appears to be a promising alternative to the current detection methods and owing to its low cost could be implemented in public health services.


Assuntos
Neoplasias Colorretais/diagnóstico , Fezes/química , RNA Neoplásico/isolamento & purificação , Colonoscopia/métodos , Neoplasias Colorretais/genética , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/métodos , Diagnóstico Precoce , Humanos , RNA Neoplásico/genética
20.
Mol Cell Biochem ; 303(1-2): 131-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17508131

RESUMO

The family of ATP-dependent chromatin-remodeling factors plays a central role in eukaryotic transcriptional regulation. These complexes can alter the structure of chromatin by mechanisms that involve nucleosome sliding, dissociation, or replacement over a specific promoter. The SWI/SNF chromatin-remodeling complex is required for transcriptional activation or repression in a subset of genes. In the present study we have isolated the spSWI/SNF complex from Schizosaccharomyces pombe, which has at least seven subunits among them spSwi1-like and the catalytic subunit spBrg1. These subunits are homologues to Swi1 and Swi2/Snf2, respectively in Sacharomyces cerevisiae. Moreover, we have demonstrated that spSWI/SNF is able to promote in vitro transcription by RNA polymerase II (RNAPII) in a reconstituted system. In our transcription assays with cellular extracts of Sc. pombe we did not observe inhibition when alpha-Swi1 antibodies were utilized, indicating that other chromatin-remodeling complexes may allow transcription in Sc. pombe.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/metabolismo , Nucleossomos/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Transcrição Gênica , Proteínas de Ciclo Celular/genética , Cromatina/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Células HeLa , Histonas/metabolismo , Humanos , Proteínas Serina-Treonina Quinases/genética , RNA Polimerase II/genética , Schizosaccharomyces/genética , Schizosaccharomyces/crescimento & desenvolvimento , Proteínas de Schizosaccharomyces pombe/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional
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