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1.
Anticancer Res ; 40(1): 109-119, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892559

RESUMO

BACKGROUND/AIM: Although molecular targeting therapy is an attractive treatment for cancer, resistance eventually develops in most cases. Here, we evaluated chemotherapeutic efficacy on non-small cell lung cancer (NSCLC) with acquired resistance to epidermal growth factor receptor inhibitors mechanistically. MATERIALS AND METHODS: Antitumor effects of taxotere were evaluated using multiple models, including xenograft, and patient-derived models developed from adenocarcinoma cancer patients. Protein expressions were analyzed after drug treatment. RESULTS: Taxotere inhibited tumor growth of NSCLC cells harboring drug resistance, and reduced the expression of phosphorylated MET proto-oncogene, receptor tyrosine kinase (MET). A tumor-inhibitory effect of taxotere was also demonstrated in vivo in xenografts in mice, patient-derived primary lung tumor cells and patient-derived xenograft with concomitant repression of phosphorylated MET expression. Chemotherapeutic and MET-targeting drug exhibited a synergistic cell growth-inhibitory effect. CONCLUSION: These results suggest that the anticancer drug taxane may be an adjuvant for lung tumors exhibiting enhanced signaling of MET networks.


Assuntos
Antineoplásicos/farmacologia , Docetaxel/farmacologia , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Oncotarget ; 10(14): 1473, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30858930

RESUMO

[This corrects the article DOI: 10.18632/oncotarget.19700.].

3.
J Pathol Transl Med ; 53(2): 94-103, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30646673

RESUMO

BACKGROUND: Development of chemotherapeutics for the treatment of advanced hepatocellular carcinoma (HCC) has been lagging. Screening of candidate therapeutic agents by using patient-derived preclinical models may facilitate drug discovery for HCC patients. METHODS: Four primary cultured HCC cells from surgically resected tumor tissues and six HCC cell lines were used for high-throughput screening of 252 drugs from the Prestwick Chemical Library. The efficacy and mechanisms of action of the candidate anti-cancer drug were analyzed via cell viability, cell cycle assays, and western blotting. RESULTS: Guanabenz acetate, which has been used as an antihypertensive drug, was screened as a candidate anti-cancer agent for HCC through a drug sensitivity assay by using the primary cultured HCC cells and HCC cell lines. Guanabenz acetate reduced HCC cell viability through apoptosis and autophagy. This occurred via inhibition of growth arrest and DNA damage-inducible protein 34, increased phosphorylation of eukaryotic initiation factor 2α, increased activating transcription factor 4, and cell cycle arrest. CONCLUSIONS: Guanabenz acetate induces endoplasmic reticulum stress-related cell death in HCC and may be repositioned as an anti-cancer therapeutic agent for HCC patients.

4.
Anticancer Res ; 38(1): 287-293, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29277785

RESUMO

BACKGROUND/AIM: To maximize success rate for development of HER2-targeted therapeutics, patient-derived xenograft (PDX) models reflecting HER2-positive gastric cancer (HER2+ GC) patients were established. MATERIALS AND METHODS: GC tissues obtained from surgery of GC patients were implanted into immune-deficient mice, and tumor tissue of HER2+ PDXs were verified of the patient-mimic HER2 expression by immunohistochemistry and explored for the feasibility by testing with Herceptin, the approved therapeutics and novel HER2 antibody therapeutics being developed. RESULTS: We obtained 5 cases of HER2+ GC PDX models reflecting patient's GC tumor, consisting of 2 cases of HER2 3+ and 2 cases of HER2 2+. Novel HER2 antibody displayed significantly improved anti-cancer efficacy in combination with Herceptin. CONCLUSION: The HER2+ GC PDX models were successfully established to be utilized for preclinical evaluation of HER2-targeting drugs and combined therapies for GC treatment, as an ideal platform of personalized tools for precision therapy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Imunológicos/uso terapêutico , Receptor ErbB-2/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Trastuzumab/uso terapêutico , Adenocarcinoma/patologia , Idoso , Animais , Antineoplásicos Imunológicos/farmacologia , Feminino , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Medicina de Precisão , Receptor ErbB-2/imunologia , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/patologia , Trastuzumab/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Oncotarget ; 8(47): 82491-82505, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29137280

RESUMO

Metabolic reprogramming as a crucial emerging hallmark of cancer is critical for tumor cells to maintain cellular bioenergetics, biosynthesis and reduction/oxidation (REDOX) balance. Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear hormone receptor regulating transcription of diverse gene sets involved in inflammation, metabolism, and suppressing tumor growth. Thiazolidinediones (TZDs), as selective PPARγ ligands, are insulin-sensitizing drugs widely prescribed for type 2 diabetic patients in the clinic. Here, we report that sumoylation of PPARγ couples lipid metabolism to tumor suppressive function of the receptor in lung cancer. We found that ligand activation of PPARγ dramatically induced de novo lipid synthesis as well as fatty acid beta (ß)-oxidation in lung cancer both in vitro and in vivo. More importantly, it turns out that PPARγ regulation of lipid metabolism was dependent on sumoylation of PPARγ. Further biochemical analysis revealed that PPARγ-mediated lipid synthesis depletes nicotinamide adenine dinucleotide phosphate (NADPH), consequently resulting in increased mitochondrial reactive oxygen species (ROS) level that subsequently disrupted REDOX balance in lung cancer. Therefore, liganded PPARγ sumoylation is not only critical for cellular lipid metabolism but also induces oxidative stress that contributes to tumor suppressive function of PPARγ. This study provides an important insight of future translational and clinical research into targeting PPARγ regulation of lipid metabolism in lung cancer patients accompanying type 2 diabetes.

6.
Neoplasia ; 19(10): 805-816, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28886423

RESUMO

A versatile biomarker for detecting colonic adenoma and colon cancer has yet to be developed. Colon cancer secreted protein-2 (CCSP-2) is a protein specifically expressed and secreted in colon adenomas and cancers. We developed a fluorescent imaging method based on CCSP-2 targeting for a more sensitive and specific detection of colorectal tumors. CCSP-2 expression was evaluated in human colon adenoma and colorectal specimens. Anti-CCSP-2 antibody was labeled with a near-infrared fluorescent dye, FPR-675, and molecular imaging of surgical human colorectal tumors was performed. Immunohistochemistry identified CCSP-2 expression in 87.0% of colorectal cancer specimens and 89.5% of colon adenoma specimens. Fluorescence imaging of surgical human colon specimens after spraying treatment with the probe permitted a clear distinction of cancer from paired normal colon tissue (target-to-background ratio, 4.09±0.42; P<.001). CCSP-2 targeting imaging was also evaluated in patient-derived colon cancer xenograft mouse and liver metastasis murine models. CCSP-2-positive colon cancer xenografts and liver metastases were visualized by near-infrared fluorescence imaging after intravenous injection of the probe, which showed significantly higher fluorescence. Our results show that CCSP-2 is a promising marker for colorectal tumor detection in clinical settings and that a CCSP-2-targeting molecular imaging strategy might improve the diagnosis of colorectal tumors in metastatic or recurrent cancers and aid in early colonoscopic detection of premalignant lesions.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/metabolismo , Imagem Molecular , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Corantes Fluorescentes , Expressão Gênica , Xenoenxertos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Microscopia Confocal , Imagem Molecular/métodos , Metástase Neoplásica , Ligação Proteica , Carga Tumoral
7.
Clin Cancer Res ; 23(23): 7340-7350, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28939743

RESUMO

Purpose: Dysregulated expression of PLD1 has emerged as a hallmark feature of colorectal cancer, which remains a major cause of mortality worldwide. Aberrant activation of Wnt/ß-catenin signaling is a critical event in the development of colorectal cancer. Here, we investigated molecular crosstalk between the Wnt/ß-catenin and PI3K/Akt pathways via inhibitor of ß-catenin and T-cell factor (ICAT), a negative regulator of Wnt/ß-catenin signaling. We also explored the effect of PLD1 inhibition on growth of colorectal cancer hyperactivated by Wnt/ß-catenin and PI3K/Akt signaling.Experimental Design: Expression of ICAT via targeting of PLD1 was assessed in vivo in ApcMin/+ mice, an AOM/DSS model, and in vitro using various colorectal cancer cells. The relationship between ICAT/PLD1 expression and prognostic survival value of 153 colorectal cancer patients was examined. The therapeutic efficacy of PLD1 inhibitor was determined using a patient-derived xenograft model carrying APC and PI3K mutations.Results: PLD1 promoted the Wnt/ß-catenin signaling pathway by selectively downregulating ICAT via the PI3K/Akt-TopBP1-E2F1 signaling pathways. Low PLD1 expression and high ICAT expression were significantly associated with increased survival in colorectal cancer patients and vice versa. Furthermore, PLD1 inhibition suppressed growth of colorectal cancer activated by the Wnt/ß-catenin and PI3K signaling pathways.Conclusions: These results suggest that PLD1 linked to ICAT mediates molecular crosstalk between the Wnt/ß-catenin and PI3K/Akt pathways and thus could be proposed as a novel colorectal cancer prognostic biomarker. These results may assist in the clinical development of a PLD1 inhibitor for treatment of colorectal cancer patients carrying APC and PI3KCA mutations. PLD1, a nodal modifier, acts as a potential therapeutic target for the treatment of colorectal cancer hyperactivated by the Wnt/ß-catenin and PI3K/Akt signaling pathways. Clin Cancer Res; 23(23); 7340-50. ©2017 AACR.


Assuntos
Neoplasias Colorretais/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosfolipase D/genética , Transdução de Sinais/genética , Regulação para Cima , Animais , Linhagem Celular Tumoral , Células Cultivadas , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos Knockout , Mutação , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipase D/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Análise de Sobrevida , Transplante Heterólogo , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo
8.
Biomaterials ; 141: 136-148, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28688285

RESUMO

Designing nanocarriers with active targeting has been increasingly emphasized as for an ideal delivery mechanism of anti-cancer therapeutic agents, but the actualization has been constrained by lack of reliable strategy ultimately applicable. Here, we designed and verified a strategy to achieve active targeting nanomedicine that works in a living body, utilizing animal models bearing a patient's tumor tissue and subjected to the same treatments that would be used in the clinic. The concept for this strategy was that a novel peptide probe and its counterpart protein, which responded to a therapy, were identified, and then the inherent ability of the peptide to target the designated tumor protein was used for active targeting in vivo. An initial dose of ionizing radiation was locally delivered to the gastric cancer (GC) tumor of a patient-derived xenograft mouse model, and phage-displayed peptide library was intravenously injected. The peptides tightly bound to the tumor were recovered, and the counterpart protein was subsequently identified. Peptide-conjugated liposomal drug showed dramatically improved therapeutic efficacy and possibility of diagnostic imaging with radiation. These results strongly suggested the potential of our strategy to achieve in vivo functional active targeting and to be applied clinically for human cancer treatment.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Lipossomos/química , Peptídeos/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanomedicina , Nanopartículas/química , Biblioteca de Peptídeos , Neoplasias Gástricas/patologia
9.
Tumour Biol ; 39(6): 1010428317706225, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28621224

RESUMO

Achaete-scute homolog 1 is a lineage oncogene of high-grade pulmonary neuroendocrine tumors. Due to the relatively few studies investigating the epigenetic regulation of achaete-scute homolog 1 expression, we wanted to address whether DNA methylation of the achaete-scute homolog 1 CpG island is associated with clinicopathological features in pulmonary neuroendocrine tumors and to investigate its effect on the expression of this gene. Here, We performed multiplex immunohistochemistry (PerkinElmer, Waltham, MA, USA) to check for achaete-scute homolog 1 and Notch homolog 1 expression in 139 pulmonary neuroendocrine tumor samples. Quantitative measurements of achaete-scute homolog 1 CpG island methylation were conducted using the MassARRAY EpiTYPER (Sequenom, San Diego, CA, USA). The correlation between immunohistochemistry data, methylation data, and clinicopathological information was analyzed. Achaete-scute homolog 1 methylation levels were increased in pulmonary neuroendocrine tumors compared to those in normal controls (0.107 vs 0.061, p < 0.001), and among the achaete-scute homolog 1 CpG island, only CpG_6 and CpG_7.8 showed higher methylation levels in pulmonary neuroendocrine tumors (0.208 and 0.135, respectively) compared to those in normal lung tissues (0.072 and 0.087, respectively; p < 0.001). Moreover, the methylation level of CpG_6.7.8 was higher in patients with stage I pulmonary neuroendocrine tumors than in patients with stage II/III pulmonary neuroendocrine tumors (0.19 ± 0.16 vs 0.14 ± 0.07, p = 0.012). The hypermethylation of CpG_6.7.8 showed an inverse correlation with achaete-scute homolog 1 protein expression (r = -0.408, p = 0.007, Spearman test). Finally, we found that CpG_6.7.8 of the achaete-scute homolog 1 CpG island is frequently hypermethylated in early-stage pulmonary neuroendocrine tumors, and this aberrant hypermethylation is negatively correlated with achaete-scute homolog 1 expression in this tumor spectrum.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Metilação de DNA/genética , Neoplasias Pulmonares/genética , Tumores Neuroendócrinos/genética , Receptor Notch1/genética , Idoso , Linhagem da Célula/genética , Ilhas de CpG/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tumores Neuroendócrinos/patologia
11.
Cancer Lett ; 385: 21-27, 2017 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-27836735

RESUMO

Autophagy plays complex roles in tumor initiation and development, and the expression of autophagy-related genes (ATGs) is differentially regulated in various cancer cells, depending on their environment. In this study, we analyzed the expressional relationship between polypyrimidine tract-binding protein 1 (PTBP1) and ATG10 in metastatic colorectal cancer. PTBP1 is associated with tumor metastasis in primary colorectal tumors and colorectal cancer liver metastasis (CLM) tissues. In addition, PTPB1 directly interacts with mRNA of ATG10, and regulates ATG10 expression level in colorectal cancer cells. Ectopic expression of PTBP1 decreased ATG10 expression, whereas down-regulation of PTBP1 increased ATG10 level. In contrast to PTBP1, expression of ATG10 was decreased in CLM tissues. Knock down of ATG10 promoted cell migration and invasion of colorectal cancer cells. Moreover, depletion of ATG10 modulated epithelial-mesenchymal transition-associated proteins in colorectal cancer cells: N-cadherin, TCF-8/ZEB1, and CD44 were up-regulated, whereas E-cadherin was down-regulated. Taken together, our findings suggest that expression of ATG10 negatively regulated by PTBP1 is associated with metastasis of colorectal cancer cells.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Movimento Celular , Neoplasias Colorretais/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Antígenos CD/metabolismo , Proteínas Relacionadas à Autofagia/genética , Caderinas/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação para Baixo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Receptores de Hialuronatos/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Transfecção , Proteínas de Transporte Vesicular/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
12.
Cancer Res ; 77(1): 142-152, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27793841

RESUMO

The RB1/E2F1 signaling pathway is frequently deregulated in colorectal cancer and has been suggested to intersect with Wnt/ß-catenin and PI3K/Akt pathways, but molecular evidence for this link is lacking. In this study, we demonstrate that phospholipase D1 (PLD1), a transcriptional target of ß-catenin/TCF4, orchestrates functional interactions between these pathways during intestinal tumor development. Overexpression of PLD1 in intestinal epithelial cells protected cells from apoptosis induced by PLD1 ablation in the Apcmin/+ mouse model of intestinal tumorigenesis. Mechanistic investigations revealed that genetic and pharmacologic targeting of PLD1 promote the E2F1-dependent apoptotic program via both miR-192/4465-mediated downregulation of RB1 and inhibition of Akt-TopBP1 pathways. Moreover, the miRNA-RB1 axis and Akt pathway also contributed to the PLD1-mediated self-renewal capacity of colon cancer-initiating cells. Finally, PLD1-driven E2F1 target gene expression positively correlated with tumor stage in patients with colorectal cancer. Overall, our findings suggest that PLD1 mediates cross-talk between multiple major signaling pathways to promote the survival and malignancy of colon cancer cells and may therefore represent an ideal signaling node for therapeutic targeting. Cancer Res; 77(1); 142-52. ©2016 AACR.


Assuntos
Apoptose/fisiologia , Neoplasias Colorretais/patologia , Fator de Transcrição E2F1/metabolismo , Fosfolipase D/metabolismo , Transdução de Sinais/fisiologia , Animais , Western Blotting , Proteínas de Transporte/metabolismo , Imunoprecipitação da Cromatina , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Proteínas de Ligação a DNA/metabolismo , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Imunoprecipitação , Estimativa de Kaplan-Meier , Camundongos , Camundongos Knockout , Proteínas Nucleares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína do Retinoblastoma/metabolismo , Análise Serial de Tecidos
13.
J Pathol ; 241(5): 614-625, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28008607

RESUMO

Infection with Helicobacter pylori is closely linked to an increased risk of gastric cancer. Although cytotoxin-associated gene A (CagA), a major virulence factor of H. pylori, is known to be a causal factor for gastric carcinogenesis, the molecular link between CagA and gastric cancer-initiating cell (CIC)-like properties remains elusive. Here, we demonstrate that CagA is required for increased expression of ß-catenin and its target CIC markers via downregulation of microRNA (miR)-320a and miR-4496. CagA promoted gastric CIC properties and was responsible for chemoresistance. miR-320a and miR-4496 attenuated the in vitro self-renewal and tumour-initiating capacity of CagA-expressing CICs by targeting ß-catenin. Moreover, miR-320a and miR-4496 decreased CagA-induced chemoresistance by targeting ATP-binding cassette, subfamily G, member 2 (ABCG2) at the transcriptional and post-transcriptional levels, respectively. Combination therapy with 5-fluorouracil and miR-320a/miR-4496 suppressed gastric tumourigenesis and metastatic potential in an orthotopic mouse model, probably via suppression of CagA-induced CIC properties and chemoresistance. Our results provide novel evidence that CIC properties, chemoresistance and tumourigenesis associated with H. pylori are linked to CagA-induced upregulation of ß-catenin and ABCG2. These data provide novel insights into the molecular mechanisms of CagA-induced carcinogenisis and the therapeutic potential of of miR-320a and miR-4496. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Infecções por Helicobacter/genética , Helicobacter pylori/patogenicidade , MicroRNAs/genética , Neoplasias Gástricas/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Carcinogênese , Autorrenovação Celular , Transformação Celular Neoplásica , Citotoxinas/genética , Citotoxinas/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/fisiologia , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Regulação para Cima , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
14.
Oncotarget ; 7(47): 77664-77682, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27765910

RESUMO

Mutation of p53 occasionally results in a gain of function, which promotes tumor growth. We asked whether destabilizing the gain-of-function protein would kill tumor cells. Downregulation of the gene reduced cell proliferation in p53-mutant cells, but not in p53-null cells, indicating that the former depended on the mutant protein for survival. Moreover, phenformin and 2-deoxyglucose suppressed cell growth and simultaneously destabilized mutant p53. The AMPK pathway, MAPK pathway, chaperone proteins and ubiquitination all contributed to this process. Interestingly, phenformin and 2-deoxyglucose also reduced tumor growth in syngeneic mice harboring the p53 mutation. Thus, destabilizing mutant p53 protein in order to kill cells exhibiting "oncogene addiction" could be a promising strategy for combatting p53 mutant tumors.


Assuntos
Desoxiglucose/administração & dosagem , Mutação , Neoplasias/patologia , Fenformin/administração & dosagem , Proteína Supressora de Tumor p53/genética , Células A549 , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Desoxiglucose/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Introdução de Genes , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Metástase Neoplásica , Fenformin/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Sci Rep ; 6: 32770, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27596264

RESUMO

Aberrant Wnt/ß-catenin signalling is implicated in the progression of several human cancers, including non-small cell lung cancer (NSCLC). However, mutations in Wnt/ß-catenin pathway components are uncommon in NSCLC, and their epigenetic control remains unclear. Here, we show that KIF3A, a member of the kinesin-2 family, plays a role in suppressing Wnt/ß-catenin signalling in NSCLC cells. KIF3A knockdown increases both ß-catenin levels and transcriptional activity with concomitant promotion of malignant potential, such as increased proliferation and migration and upregulation of stemness markers. Because KIF3A binds ß-arrestin, KIF3A depletion allows ß-arrestin to form a complex with DVL2 and axin, stabilizing ß-catenin. Although primary cilia, whose biogenesis requires KIF3A, are thought to restrain the Wnt response, pharmacological inhibition of ciliogenesis failed to increase ß-catenin activity in NSCLC cells. A correlation between KIF3A loss and a poorer NSCLC prognosis as well as ß-catenin and cyclin D1 upregulation further suggests that KIF3A suppresses Wnt/ß-catenin signalling and tumourigenesis in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Cílios/metabolismo , Cinesina/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores Wnt/metabolismo , Transdução de Sinais , beta Catenina/metabolismo , beta-Arrestinas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Cinesina/genética , Neoplasias Pulmonares/patologia , Ligação Proteica
16.
Oncotarget ; 7(40): 65957-65967, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27602754

RESUMO

The tumor necrosis factor-related apoptosis inducing ligand (TRAIL) preferentially induces apoptosis in cancer cells. However, many tumors are resistant to TRAIL-induced apoptosis, and resistance mechanisms are not fully understood. To identify novel regulatory molecules of TRAIL resistance, we screened a siRNA library targeting the human kinome, and NEK4 (NIMA-related kinase-4) was identified. Knockdown of NEK4 sensitized TRAIL-resistant cancer cells and in vivo xenografts to cell death. In contrast, over expression of NEK4 suppressed TRAIL-induced cell death in TRAIL-sensitive cancer cells. In addition, loss of NEK4 resulted in decrease of the anti-apoptotic protein survivin, but an increase in apoptotic cell death. Interestingly, NEK4 was highly upregulated in tumor tissues derived from patients with lung cancer and colon cancer. These results suggest that inhibition of NEK4 sensitizes cancer cells to TRAIL-induced apoptosis by regulation of survivin expression.


Assuntos
Apoptose , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Pulmonares/patologia , Quinases Relacionadas a NIMA/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Animais , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Nus , Prognóstico , Survivina , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Arch Pharm Res ; 39(8): 1151-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27515054

RESUMO

Intracellular accumulation of free zinc contributes to neuronal death in brain injuries such as ischemia and epilepsy. Pyruvate, a glucose metabolite, has been shown to block zinc neurotoxicity. However, it is largely unknown how pyruvate shows such a selective and remarkable protective effect. In this study, we sought to find a plausible mechanism of pyruvate protection against zinc toxicity. Pyruvate almost completely blocked cortical neuronal death induced by zinc, yet showed no protective effects against death induced by calcium (ionomycin, NMDA) or ferrous iron. Of the TCA cycle intermediates, citrate, isocitrate, and to a lesser extent oxaloacetate, protected against zinc toxicity. We then noted with LC-MS/MS assay that exposure to pyruvate, and to a lesser degree oxaloacetate, increased levels of citrate and isocitrate, which are known zinc chelators. While pyruvate added only during zinc exposure did not reduce zinc toxicity, citrate and isocitrate added only during zinc exposure, as did extracellular zinc chelator CaEDTA, completely blocked it. Furthermore, addition of pyruvate after zinc exposure substantially reduced intracellular zinc levels. Our results suggest that the remarkable protective effect of pyruvate against zinc cytotoxicity may be mediated indirectly by the accumulation of intracellular citrate and isocitrate, which act as intracellular zinc chelators.


Assuntos
Quelantes/farmacologia , Ácido Cítrico/farmacologia , Isocitratos/farmacologia , Fármacos Neuroprotetores/farmacologia , Ácido Pirúvico/farmacologia , Zinco/toxicidade , Animais , Células Cultivadas , Técnicas de Cocultura , Camundongos , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia
18.
Oncotarget ; 7(35): 57186-57196, 2016 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-27527864

RESUMO

Autophagy is a catabolic degradation process and maintains cellular homeostasis. And autophagy is activated in response to various stress conditions. Although O-GlcNAcylation functions a sensor for nutrient and stress, the relationship between O-GlcNAcylation and autophagy is largely unknown. Here, we identified that ATG4B is novel target for O-GlcNAcylation under metabolic stress condition. Treatment with PugNAc, an O-GlcNAcase inhibitor increased activation of autophagy in SH-SY5Y cells. Both bimolecular fluorescence complementation and immunoprecipitation assay indicated that OGT directly interacts with ATG4B in SH-SY5Y cells. We also found that the O-GlcNAcylated ATG4B was increased in autophagy activation conditions, and down-regulation of OGT reduces O-GlcNAcylation of ATG4B under low glucose condition. Furthermore, the proteolytic activity of ATG4B for LC3 cleavage was enhanced in PugNAc-treated cells. Taken together, these results imply that O-GlcNAcylation of ATG4B regulates autophagy activation by increasing its proteolytic activity under metabolic stress condition.


Assuntos
Proteínas Relacionadas à Autofagia/química , Autofagia , Cisteína Endopeptidases/química , Regulação Enzimológica da Expressão Gênica , Oxigenases de Função Mista/química , N-Acetilglucosaminiltransferases/metabolismo , Acetilglucosamina/análogos & derivados , Acetilglucosamina/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Fibroblastos/metabolismo , Corantes Fluorescentes/química , Glucose/química , Humanos , Imunoprecipitação , Luciferases/metabolismo , Espectrometria de Massas , Camundongos , Oximas/metabolismo , Fenilcarbamatos/metabolismo , Transdução de Sinais , beta-N-Acetil-Hexosaminidases/metabolismo
19.
Mol Cancer Ther ; 14(11): 2613-22, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26351320

RESUMO

The MET receptor tyrosine kinase, the receptor for hepatocyte growth factor (HGF), has been implicated in cancer growth, invasion, migration, angiogenesis, and metastasis in a broad variety of human cancers, including human hepatocellular carcinoma (HCC). Recently, MET was suggested to be a potential target for the personalized treatment of HCC with an active HGF-MET signaling pathway. However, the mechanisms of resistance to MET inhibitors need to be elucidated to provide effective treatment. Here, we show that HCC cells exhibit different sensitivities to the MET inhibitor PHA665752, depending on the phosphorylation status of FGFR. Treatment of cells expressing both phospho-FGFR and phospho-MET with the inhibitor PHA665752 did not cause growth inhibition and cell death, whereas treatment with AZD4547, a pan-FGFR inhibitor, resulted in decreased colony formation and cleavage of caspase-3. Moreover, silencing of endogenous FGFR1 and FGFR2 by RNAi of HCC cells expressing phospho-FGFR, phospho-FGFR2, and phospho-MET overcame the resistance to PHA665752 treatment. Treatment of primary cancer cells from patients with HCC expressing both phospho-FGFR and phospho-MET with PHA665752 did not induce cell death, whereas AZD4547 treatment induced cell death through the cleavage of caspase-3. In addition, treatment of cells resistant to PHA665752 with AZD4547 abrogated the activation of downstream effectors of cell growth, proliferation, and survival. On the basis of these results, we conclude that the FGFR pathway is critical for HCC survival, and that targeting this pathway with AZD4547 may be beneficial for the treatment of patients with HCC-expressing phospho-FGFR and phospho-MET.


Assuntos
Proteínas Proto-Oncogênicas c-met/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Indóis/farmacologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Microscopia Confocal , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/genética , Pirazóis/farmacologia , Interferência de RNA , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sulfonas/farmacologia
20.
PLoS One ; 10(3): e0119379, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25781604

RESUMO

Histone modification plays a pivotal role on gene regulation, as regarded as global epigenetic markers, especially in tumor related genes. Hence, chemical approaches targeting histone-modifying enzymes have emerged onto the main stage of anticancer drug discovery. Here, we investigated the therapeutic potentials and mechanistic roles of the recently developed histone deacetylase inhibitor, CG200745, in non-small cell lung cancer cells. Treatment with CG200745 increased the global level of histone acetylation, resulting in the inhibition of cell proliferation. ChIP-on-chip analysis with an H4K16ac antibody showed altered H4K16 acetylation on genes critical for cell growth inhibition, although decreased at the transcription start site of a subset of genes. Altered H4K16ac was associated with changes in mRNA expression of the corresponding genes, which were further validated in quantitative RT-PCR and western blotting assays. Our results demonstrated that CG200745 causes NSCLC cell growth inhibition through epigenetic modification of critical genes in cancer cell survival, providing pivotal clues as a promising chemotherapeutics against lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Neoplasias Pulmonares/patologia , Naftalenos/farmacologia , Acetilação , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular , Imunoprecipitação da Cromatina , Epigenômica , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
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