Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
1.
Int J Mol Sci ; 22(8)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918878

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome, characterized from pathological changes in lipid and carbohydrate metabolism. Its main characteristics are excessive lipid accumulation and oxidative stress, which create a lipotoxic environment in hepatocytes leading to liver injury. Recently, many studies have focused on the identification of the genetic and epigenetic modifications that also contribute to NAFLD pathogenesis and their prognostic implications. The present review is aimed to discuss on cellular and metabolic alterations associated with NAFLD, which can be helpful to identify new noninvasive biomarkers. The identification of accumulated lipids in the cell membranes, as well as circulating cytokeratins and exosomes, provides new insights in understanding of NAFLD. This review also suggests that lifestyle modifications remain the main prevention and/or treatment for NAFLD.


Assuntos
Biomarcadores , Suscetibilidade a Doenças , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Citocinas/metabolismo , Dieta , Gerenciamento Clínico , Exercício Físico , Exossomos , Ácidos Graxos/metabolismo , Comportamentos Relacionados com a Saúde , Hepatócitos/metabolismo , Humanos , Estilo de Vida , Metabolismo dos Lipídeos , Lipidômica , Lipídeos/sangue , Microbiota , Hepatopatia Gordurosa não Alcoólica/diagnóstico
2.
Int J Mol Sci ; 19(5)2018 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-29783729

RESUMO

Chlorogenic acid (CGA) is a polyphenol present in many human dietary foods. Several studies indicated a beneficial role of CGA in the prevention of cancer and an enhancement of chemotherapy when combined with CGA in the treatment of human hepatocarcinoma (HCC). Drug toxicity, resistance and subsequent disease progression represent a problem in HCC management, although treatment with the multikinase inhibitor Regorafenib improved overall survival. This study focused on the evaluation of the effects of combined treatment using both low Regorafenib concentrations and CGA as natural compound in HCC cells. The analysis of cell proliferation by Ki67 staining and cell cycle progression showed that CGA enhanced Regorafenib-mediated cell growth inhibition. Moreover, CGA potentiated the apoptotic effect of Regorafenib by the activation of the pro-apoptotic Annexin V, Bax and Caspase 3/7 and the inhibition of anti-apoptotic Bcl2 and Bcl-xL. Combined treatments were also effective in inhibiting cell motility. The mechanisms underlying the positive effects of combining CGA and Regorafenib were also addressed and an increased inhibition of MAPK (mitogen-activated protein kinase)and PI3K/Akt/mTORC (phosphatidylinositol-3-kinase (PI3K)/Akt and the mammalian target of rapamycin (mTOR) signaling was observed. Overall, these data demonstrated that co-treatment with Regorafenib and CGA enhanced Regorafenib action, reducing its cytotoxicity in HCC cells. In conclusion, this drug combination could be considered as a safe and more effective approach in HCC therapy.


Assuntos
Antineoplásicos/farmacologia , Ácido Clorogênico/farmacologia , Sinergismo Farmacológico , Compostos de Fenilureia/farmacologia , Piridinas/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Sistema de Sinalização das MAP Quinases , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
3.
J Cell Physiol ; 230(12): 2973-80, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25893829

RESUMO

Quercetin, the major constituent of flavonoid and widely present in fruits and vegetables, is an attractive compound for cancer prevention due to its beneficial anti proliferative effects, showing a crucial role in the regulation of apoptosis and cell cycle signaling. In vitro studies have demonstrated that quercetin specifically influences colon cancer cell proliferation. Our experiments, using human colon adenocarcinoma cells, confirmed the anti proliferative effect of quercetin and gave intriguing new insight in to the knowledge of the mechanisms involved. We observed a significant increase in the expression of the endocannabinoids receptor (CB1-R) after quercetin treatment. CB1-R can be considered an estrogen responsive receptor and quercetin, having a structure similar to that of the estrogens, can interact with CB1-R leading to the regulation of cell growth. In order to clarify the contribution of the CB1-R to the quercetin action, we investigated some of the principal molecular pathways that are inhibited or activated by this natural compound. In particular we detected the inhibition of the major survival signals like the PI3K/Akt/mTOR and an induction of the pro apoptotic JNK/JUN pathways. Interestingly, the metabolism of ß-catenin was modified by flavonoid both directly and through activated CB1-R. In all the experiments done, the quercetin action has proven to be reinforced by anandamide (Met-F-AEA), a CB1-R agonist, and partially counteracted by SR141716, a CB1-R antagonist. These findings open new perspectives for anticancer therapeutic strategies.


Assuntos
Adenocarcinoma/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Agonistas de Receptores de Canabinoides/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Quercetina/farmacologia , Receptor CB1 de Canabinoide/agonistas , Adenocarcinoma/genética , Adenocarcinoma/patologia , Células CACO-2 , Movimento Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Humanos , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
4.
BMC Cancer ; 14: 43, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24468103

RESUMO

BACKGROUND: Thrombocytopenia has been reported to be associated with small size HCCs, and thrombocytosis to be associated with large size HCCs. The aim was to examine the effects of platelets in relation to HCC cell growth. METHODS: The effects of time-expired pooled normal human platelets were examined on human HCC cell line growth and invasion. RESULTS: Blood platelet numbers increased with increasing HCC tumor size and portal vein invasion. Platelet extracts enhanced cell growth in 4 human HCC cell lines, as well as cell migration, medium AFP levels and decreased apoptosis. Cell invasion was significantly enhanced, using a Matrigel-coated trans-well membrane and 3D (Real-Time Imaging) invasion assay. Western blots showed that platelets caused enhanced phospho-ERK and phospho-JNK signaling and anti-apoptotic effect with increase of Bcl-xL (anti-apoptotic marker) and decrease of Bid (pro-apoptotic marker) levels. Their growth effects were blocked by a JNK inhibitor. CONCLUSIONS: Platelets stimulated growth and invasion of several HCC cell lines in vitro, suggesting that platelets or platelet growth factors could be a potential pharmacological target.


Assuntos
Plaquetas/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Apoptose , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Transdução de Sinais , Esferoides Celulares , Células Tumorais Cultivadas
5.
BMC Cancer ; 14: 351, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24885890

RESUMO

BACKGROUND: Platelets are frequently altered in hepatocellular carcinoma (HCC) patients. Platelet lysates (hPL) can enhance HCC cell growth and decrease apoptosis. The aims were to evaluate whether hPL can modulate the actions of sorafenib or regorafenib, two clinical HCC multikinase antagonists. METHODS: Several human HCC cell lines were grown in the presence and absence of sorafenib or regorafenib, with or without hPL. Growth was measured by MTT assay, apoptosis was assessed by Annexin V and by western blot, and autophagy and MAPK growth signaling were also measured by western blot, and migration and invasion were measured by standard in vitro assays. RESULTS: Both sorafenib and regorafenib-mediated inhibition of cell growth, migration and invasion were all antagonized by hPL. Drug-mediated apoptosis and decrease in phospho-ERK levels were both blocked by hPL, which also increased anti-apoptotic phospho-STAT, Bax and Bcl-xL levels. Preliminary data, obtained with epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I), included in hPL, revealed that these factors were able to antagonized sorafenib in a proliferation assay, in particular when used in combination. CONCLUSIONS: Platelet factors can antagonize sorafenib or regorafenib-mediated growth inhibition and apoptosis in HCC cells. The modulation of platelet activity or numbers has the potential to enhance multikinase drug actions.


Assuntos
Antineoplásicos/farmacologia , Plaquetas/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Hepatocelular/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática , Fator de Crescimento Epidérmico/sangue , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Hep G2 , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias Hepáticas/patologia , Invasividade Neoplásica , Niacinamida/farmacologia , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Sorafenibe , Fatores de Tempo
6.
J Cell Physiol ; 228(2): 292-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22777740

RESUMO

To evaluate the growth-inhibitory properties of the potent multi-kinase antagonist Regorafenib (Fluoro-Sorafenib), which was synthesized as a more potent Sorafenib, a Raf inhibitor and to determine whether similar mechanisms were involved, human hepatoma cell lines were grown in the presence or absence of Regorafanib and examined for growth inhibition. Western blots were performed for Raf targets, apoptosis, and autophagy. Regorafenib inhibited growth of human Hep3B, PLC/PRF/5, and HepG2 cells in a concentration- and time-dependent manner. Multiple signaling pathways were altered, including MAP kinases phospho-ERK and phospho-JNK and its target phospho-c-Jun. There was evidence for apoptosis by FACS, cleavage of caspases and increased Bax levels; as well as induction of autophagy, as judged by increased Beclin-1 and LC3 (II) levels. Prolonged drug exposure resulted in cell quiescence. Full growth recovery occurred after drug removal, unlike with doxorubicin chemotherapy. Regorafenib is a potent inhibitor of cell growth. Cells surviving Regorafenib treatment remain viable, but quiescent and capable of regrowth following drug removal. The reversibility of tumor cell growth suppression after drug removal may have clinical implications.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/metabolismo , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos , Transdução de Sinais/efeitos dos fármacos
7.
J Cell Physiol ; 228(6): 1344-50, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23169148

RESUMO

Sorafenib was shown in clinical trial to enhance survival in hepatocellular carcinoma (HCC) patients, but with minimal tumor shrinkage. To correlate several indices of HCC growth at various drug concentrations, HCC cells were grown in various low concentrations of two multikinase inhibitors, regorafenib (Stivarga) and sorafenib (Nexavar) and their effects were examined on alpha-fetoprotein (AFP), cell growth, migration, and invasion. In two AFP positive human HCC cell lines, AFP was inhibited at 0.1-1 µM drug concentrations. Cell migration and invasion were also inhibited at similar low drug concentrations. However, 10-fold higher drug concentrations were required to inhibit cell growth in both AFP positive and negative cells. To investigate this concentration discrepancy of effects, cells were then grown for prolonged times and sub-cultured in low drug concentrations and then their growth was re-tested. The growth in these drug-exposed cells was found to be slower than cells without prior drug exposure and they were also more sensitive to subsequent drug challenge. Evidence was also found for changes in cell signaling pathways in these slow-growth cells. Low multikinase inhibitor concentrations thus modulate several aspects of HCC cell biology.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/enzimologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/enzimologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , alfa-Fetoproteínas/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Invasividade Neoplásica , Niacinamida/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sorafenibe , Fatores de Tempo , alfa-Fetoproteínas/genética
8.
Front Oncol ; 13: 1129832, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874116

RESUMO

Introduction: Paclitaxel (PTX) interferes with microtubule architecture by binding to ß-tubulin, thereby blocking progression at the G2/M phase and inducing apoptosis. This study aimed to investigate molecular processes underlying PTX-mediated resistance in gastric cancer (GC) cells. Methods: PTX-mediated resistance involves many processes, and in this work some of the factors involved in the resistance mechanism were identified by comparing two GC lines with PTX induced resistance to their sensitive counterparts. Results: Thus, the key feature of PTX-resistant cells was the overexpression of pro-angiogenic factors such as VEGFA, VEGFC, and Ang2, known to support tumor cell growth. A second relevant change detected in PTX-resistant lines was the elevated level of TUBßIII, a tubulin isoform that opposes microtubule stabilization. A third identified factor contributing to PTX-resistance was P-glycoprotein (P-gp), a transporter responsible for chemotherapy efflux from the cells, highly expressed in PTX-resistant lines. Discussion: These findings were in line with a greater sensitivity of resistant cells to treatment with both Ramucirumab and Elacridar. Ramucirumab significantly reduced the expression of angiogenic molecules and TUBßIII, while Elacridar restored the access of chemotherapy, recovering its anti-mitotic and pro-apoptotic effects. Finally, this study highlighted the role played by exosomes in spreading factors responsible for resistance in the tumor microenvironment.

10.
Biomedicines ; 11(10)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37893095

RESUMO

Metastatic gastric cancer (mGC) often has a poor prognosis and may benefit from a few targeted therapies. Ramucirumab-based anti-angiogenic therapy targeting the VEGFR2 represents a milestone in the second-line treatment of mGC. Several studies on different cancers are focusing on the major VEGFR2 ligand status, meaning VEGFA gene copy number and protein overexpression, as a prognostic marker and predictor of response to anti-angiogenic therapy. Following this insight, our study aims to examine the role of VEGFA status as a predictive biomarker for the outcome of second-line therapy with Ramucirumab and paclitaxel in mGC patients. To this purpose, the copy number of the VEGFA gene, by fluorescence in situ hybridization experiments, and its expression in tumor tissue as well as the density of micro-vessels, by immunohistochemistry experiments, were assessed in samples derived from mGC patients. This analysis found that amplification of VEGFA concomitantly with VEGFA overexpression and overexpression of VEGFA with micro-vessels density are more represented in patients showing disease control during treatment with Ramucirumab. In addition, in the analyzed series, it was found that amplification was not always associated with overexpression of VEGFA, but overexpression of VEGFA correlates with high micro-vessel density. In conclusion, overexpression of VEGFA could emerge as a potential biomarker to predict the response to anti-angiogenic therapy.

11.
Front Oncol ; 12: 862116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463372

RESUMO

The combination of paclitaxel and ramucirumab is the second-line therapy of choice in the treatment of advanced gastric cancer. To date, no biomarkers are available in gastric cancer to predict the outcome of antiangiogenic therapy. The present prospective study included 35 patients undergoing second-line therapy with ramucirumab and paclitaxel. Serum samples were systematically collected from the beginning of therapy and at each cycle until disease progression. Multiplex analysis of a panel of angiogenic factors identified markers for which the changes at defined time intervals were significantly different in patients with progression-free survival ≤3 (Rapid Progression Group) compared to those with progression-free survival >3 (Control Disease Group). Comparative analysis revealed significantly different results in the two groups of patients for VEGFC and Angiopoietin-2, both involved in angiogenesis and lymphangiogenesis. VEGFC increased in the progressive-disease group, while it decreased in the control-disease group. This decrease persisted beyond the third cycle, and it was statistically significant compared to the basal level in patients with longer progression-free survival. Angiopoietin-2 decreased significantly after 2 months of therapy. At progression time, there was a significant increase in VEGFC and Angiopoietin-2, suggesting the activation pathways counteracting the blockade of VEGFR2 by ramucirumab. Overall results showed that a greater change in VEGFC and Angiopoietin-2 levels measured at the beginning of the third cycle of therapy corresponded to a lower risk of progression and thus to longer progression-free survival.

12.
Lipids Health Dis ; 10: 10, 2011 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21244676

RESUMO

BACKGROUND: n-3 and n-6 polyunsaturated fatty acids (PUFAs) are the two major classes of PUFAs encountered in the diet, and both classes of fatty acids are required for normal human health. Moreover, PUFAs have effects on diverse pathological processes impacting chronic disease, such as cardiovascular and immune disease, neurological disease, and cancer. AIM: To investigate the effects of eicosapentaenoic acid (EPA) and arachidonic acid (ARA) on the proliferation and apoptosis of human hepatoma cell line HepG2 after exposure to increasing concentrations of EPA or ARA for 48 h. Moreover, in the same cells the gene expression of Fatty Acid Synthase (FAS) and 3-Hydroxy-3-Methyl-Glutaryl Coenzyme A Reductase (HMG-CoAR) was also investigated. METHOD: Cell growth and apoptosis were assayed by MTT and ELISA test, respectively after cell exposure to increasing concentrations of EPA and ARA. Reverse-transcription and real-time PCR was used to detect FAS and HMG-CoAR mRNA levels in treated cells. RESULTS: Our findings show that EPA inhibits HepG2 cell growth in a dose-dependent manner, starting from 25 µM (P < 0.01, one-way ANOVA test and Dunnett's post test) and exerts a statistically significant pro-apoptotic effect already at 1 µM of EPA. Higher doses of ARA were need to obtain a statistically significant inhibition of cell proliferation and a pro-apoptotic effect in these cells (100 µM, P < 0.01, one-way ANOVA test and Dunnett's post test). Moreover, a down-regulation of FAS and HMG-CoAR gene expression was observed after EPA and ARA treatment in HepG2 cells, starting at 10 µM (P < 0.05, one-way ANOVA test and Dunnett's post test). CONCLUSION: Our results demonstrate that EPA and ARA inhibit HepG2 cell proliferation and induce apoptosis. The down-regulation of FAS and HMG-CoAR gene expression by EPA and ARA might be one of the mechanisms for the anti-proliferative properties of PUFAs in an in vitro model of hepatocellular carcinoma.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Araquidônico/farmacologia , Ácido Eicosapentaenoico/farmacologia , Ácido Graxo Sintases/biossíntese , Hidroximetilglutaril-CoA Redutases/biossíntese , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Ácido Graxo Sintases/genética , Células Hep G2 , Humanos , Hidroximetilglutaril-CoA Redutases/genética
13.
Lipids Health Dis ; 9: 135, 2010 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-21118482

RESUMO

BACKGROUND: PUFAs are potent inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an enzyme catalyzing the conversion of HMGCoA to mevalonate, the rate limiting step in cholesterol biosynthesis. Statins represent a class of drugs that are widely used to treat hypercholesterolemia for their ability to inhibit cholesterol biosynthesis and to up-regulate the synthesis of Low Density Lipoprotein (LDL) receptors in the liver. PUFAs mediate many, if not all, actions of statins and this could be one mechanism by which they lower cholesterol levels. The purpose of this study was to investigate whether combined treatment with Eicosapentaenoic acid (EPA) and lovastatin enhanced the regulatory effect on gene expression of HMGCoA reductase and LDL receptor in HepG2 cell line. RESULTS: The combined treatment with EPA and lovastatin enhanced the regulatory effect on gene expression of HMGCoA reductase and LDL receptor in HepG2 cell line. Moreover, we detected a synergistic effect on the inhibition of cancer cell proliferation obtained by combination of EPA and Lovastatin. CONCLUSIONS: The use of EPA, in combination with low doses of Lovastatin may have potential value in treatment of neoplastic diseases.


Assuntos
Ácido Eicosapentaenoico/farmacologia , Hidroximetilglutaril-CoA Redutases/metabolismo , Lovastatina/farmacologia , Receptores de LDL/metabolismo , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos
14.
Sci Rep ; 10(1): 7162, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32346056

RESUMO

Ramucirumab is approved both as monotherapy and in combination with Paclitaxel for advanced gastric cancer in patients with disease progression after chemotherapy. In tumor cells, the VEGFA-VEGFR2 binding activates autocrine survival and migration signaling in angiogenesis independent manner. The present in vitro study investigated the effects of single and combined treatments with Ramucirumab and Paclitaxel on cell growth and migration highlighting the mechanisms underlying the interaction between the two drugs in gastric cancer cells. Cell growth and motility were investigated in human gastric cancer cell lines characterized by different tumorigenicity. The inhibitory effect on cell growth exerted by both drugs was potentiated by their combination and was synergistic. Ramucirumab was able to enhance the inhibitory effect exerted by Paclitaxel on cell cycle progression. A synergistic action was also observed in the expression of proteins crucial for cell motility, microtubule organization and epithelial-mesenchymal transition. Furthermore, synergistic inhibition of VEGFR2 expression was obtained by the drug combination. These findings highlighted the importance of the combined treatment to strongly inhibit all the main molecules of both PI3K/Akt/mTOR and MAPK pathways thus preventing possible reactivations due to cross-talk phenomena. The combined treatment with Ramucirumab seems to be a promising option to overcome the Paclitaxel resistance.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Paclitaxel/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Paclitaxel/agonistas , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Ramucirumab
15.
J Leukoc Biol ; 108(2): 633-646, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32170872

RESUMO

Gastric cancer (GC) is characterized by extreme heterogeneity due to histopathological differences, molecular characteristics, and immune gene expression signature. Until recently, several targeted therapies failed due to this complexity. The recent immunotherapy resulted in more effective and safe approaches in several malignancies. All tumors could be considered potentially immunogenic and the new knowledge regarding the interactions among tumor cells, immune cells, and tumor microenvironment (TME) allowed to reverse possible immune resistance. The immune response is a complex multisteps process that finely regulates the balance between the recognition of non-self and the prevention of autoimmunity. Cancer cells can use these pathways to suppress tumor immunity as a major mechanism of immune resistance. The recent molecular classifications of GCs by The Cancer Genome Atlas (TCGA) and by the Asian Cancer Research (ACRG) networks, together with the identification of multiple biomarkers, open new perspectives for stratification of patients who might benefit from a long-term immune checkpoint therapy. One of the major processes that contribute to an immunosuppressive microenvironment is represented by tumor angiogenesis. The cellular mechanisms inducing both angiogenesis and immunosuppressive responses are often reached by the same cell types and soluble factors, such as vascular endothelial growth factor A (VEGFA). Recent studies point out that combinatorial strategies should be adapted as useful therapeutic approach to reverse the immunosuppressive status of microenvironment occurring in a relevant percentage of gastric tumors.


Assuntos
Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , Imunomodulação , Transdução de Sinais , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/metabolismo , Animais , Antineoplásicos Imunológicos , Gerenciamento Clínico , Suscetibilidade a Doenças , Humanos , Imunomodulação/efeitos dos fármacos , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Neovascularização Patológica , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/terapia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
16.
Cancers (Basel) ; 12(3)2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32164265

RESUMO

HCC (hepatocellular carcinoma) is the second leading cause of cancer deaths worldwide, with several etiologic causes, mostly inflammation-associated. Different inflammatory responses in the liver can be triggered by different etiological agents. The inflammatory process can be resolved or be persistent, depending on the etiology and multiple other factors. Chronic inflammation, tissue remodeling, genetic alterations, and modifications in cellular signaling are considered to be key processes promoting immunosuppression. The progressive immunosuppression leads to the inactivation of anti-tumor immunity involved in HCC carcinogenesis and progression. Tumor cellular processes including DNA damage, necrosis, and ER (endoplasmic reticulum) stress can affect both immune-surveillance and cancer-promoting inflammation, supporting a mutual interdependence. Here, we review the current understanding of how chronic liver injury and inflammation is triggered and sustained, and how inflammation is linked to HCC. The identification of many hepatic microenvironmental inflammatory processes and their effector molecules, has resulted in extensive translational work and promising clinical trials of new immunomodulatory agents.

17.
Int J Cancer ; 124(6): 1322-9, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19058178

RESUMO

N(6)-isopentenyladenosine (i6A) is a modified nucleoside with a pentaatomic isopentenyl derived from mevalonate that induces inhibition of tumor cell proliferation and apoptosis in several tumor cell lines. In this study, we reported that N(6)-isopentenyladenosine inhibited the proliferation and promotes apoptosis in DLD1 human colon cancer cells. It suppressed the proliferation of cells through inhibition of DNA synthesis, causing a cell cycle arrest that correlated with a decrease in the levels of cyclin E, cyclin A and cyclin D1 and with a concomitant increase in the levels of cyclin-dependent kinase inhibitor p21waf and p27kip1. Moreover, it induced apoptosis through an increase in the number of annexin V-positive cells, a downregulation of antiapoptotic products and caspase-3 activation. The apoptotic effects of N(6)-isopentenyladenosine were accompanied by sustained phosphorylation and activation of c-jun N-terminal kinase (JNK) that induced phosphorylation of c-jun. Overall, our data show that JNK, could play an important role in i6A-mediated apoptosis in DLD1 human colon cancer cells.


Assuntos
Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Isopenteniladenosina/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fosforilação , RNA Mensageiro/genética , RNA Neoplásico/genética
18.
Immunopharmacol Immunotoxicol ; 31(1): 108-16, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19234959

RESUMO

Previous in vitro and in vivo studies have suggested that lactobacilli can exert antiproliferative effects on the gastrointestinal epithelium. However, their role in affecting the cellular proliferative mechanisms is not completely clear. The aim of this study was to investigate the effects of increasing concentrations of Lactobacillus rhamnosus strain GG (L. GG) homogenate on cell growth and proliferation (by MTT, [3H]-thymidine incorporation and polyamine biosynthesis) in neoplasms originating from different gastrointestinal tracts. Thus, HGC-27 human gastric cancer cells and DLD-1 human colonic adenocarcinoma cells were evaluated. Besides, in order to verify which bacterial fraction was involved in the antiproliferative effects, the cytoplasm and cell wall extracts were tested separately. Gastric HGC-27 and colonic DLD-1 cells showed significant differences in their proliferative behavior, in particular in their polyamine profile and biosynthesis. Notwithstanding, one and the other proved to be sensitive to the growth inhibition by the highest concentrations of bacterial homogenate. Both HGC-27 and DLD-1 cells were resistant to the bacterial cell wall fractions, whereas increasing cytoplasm fraction concentrations induced an evident antiproliferative effect. These data suggest that cytoplasm extracts could be the responsible for L. GG action on proliferation in these two cell lines from gastric and colonic neoplasms.


Assuntos
Poliaminas Biogênicas/biossíntese , Extratos Celulares/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Lacticaseibacillus rhamnosus/química , Neoplasias Gástricas/patologia , Vias Biossintéticas/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Citoplasma/química , Relação Dose-Resposta a Droga , Humanos , Ornitina Descarboxilase/metabolismo , Probióticos/química , Putrescina/biossíntese , Espermidina/biossíntese , Espermina/biossíntese , Neoplasias Gástricas/metabolismo
19.
Cancers (Basel) ; 11(6)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181647

RESUMO

Several new multikinase inhibitors have recently been introduced into clinical practice for hepatocellular carcinoma (HCC) therapy. Small increases in survival were reported as well as considerable toxicity. There is thus a need for effective therapies with lower toxicities. We examined whether a combination of sorafenib and regorafenib might also be effective at very low concentrations, with resulting potential for lessened clinical toxicity. MTT test, clonogenic assay, Ki67 staining and cell cycle analysis were assessed for cell proliferation and Annexin V and western blotting analysis relative to the expression of cleaved Caspase-3 and BID for cell apoptosis. In these experimental conditions cell growth and migration were potently inhibited and apoptosis induced even in HCC cells producing high alpha fetoprotein (AFP) levels (clinically worse prognosis). The combination also inhibited levels of the two HCC biomarkers, AFP and des gamma carboxy prothrombin (DCP). Additional inhibition of Vascular Endothelial Growth Factor Receptor (VEGFR) or Insulin-like Growth Factor 1 Receptor (IGF1R) enhanced effects on AFP and DCP levels, cell growth inhibition and MAPK and PI3K/Akt signaling inhibition due to sorafenib/regorafenib combination. These combinations have the potential for decreased toxicity while simultaneously enhancing therapeutic effects. This potential decrease in toxicity is being explored in ongoing studies.

20.
Cells ; 8(8)2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31349740

RESUMO

Extracellular vesicles (EVs) are involved in intercellular communication during carcinogenesis, and cancer cells are able to secrete EVs, in particular exosomes containing molecules, that can be transferred to recipient cells to induce pathological processes and significant modifications, as metastasis, increase of proliferation, and carcinogenesis evolution. FZD proteins, a family of receptors comprised in the Wnt signaling pathway, play an important role in carcinogenesis of the gastroenteric tract. Here, a still unknown role of Frizzled 10 (FZD10) protein was identified. In particular, the presence of FZD10 and FZD10-mRNA in exosomes extracted from culture medium of the untreated colorectal, gastric, hepatic, and cholangio cancer cell lines, was detected. A substantial reduction in the FZD10 and FZD10-mRNA level was achieved in FZD10-mRNA silenced cells and in their corresponding exosomes. Concomitantly, a significant decrease in viability of the silenced cells compared to their respective controls was observed. Notably, the incubation of silenced cells with the exosomes extracted from culture medium of the same untreated cells promoted the restoration of the cell viability and, also, of the FZD10 and FZD10-mRNA level, thus indicating that the FZD10 and FZD10-mRNA delivering exosomes may be potential messengers of cancer reactivation and play an active role in long-distance metastatization.


Assuntos
Exossomos/metabolismo , Receptores Frizzled/metabolismo , Neoplasias/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Vesículas Extracelulares/metabolismo , Imunofluorescência , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa