RESUMO
Dysregulated Wnt signaling is associated with malignant oncogenic transformation, especially in colon cancer. Recently, numerous drugs have been developed based on tumorigenesis biomarkers, thus having high potential as drug targets. Likewise, WNT/ß-catenin pathway members are attractive therapeutic targets for colon cancer and are currently in various stages of development. However, although inhibitors of proteins regulating the WNT/ß-catenin signaling pathway have been extensively studied, they have yet to be clinically approved, and the underlying molecular mechanism(s) of their anticancer effects remain poorly understood. Herein, we show that a novel WNT/ß-catenin inhibitor, DGG-300273, inhibits colon cancer cell growth in a Wnt-dependent manner due to upregulation of the BCL2-family protein Bim and caspase-dependent apoptotic cell death. Additionally, DGG-300273-mediated cell death occurs by increased reactive oxygen species (ROS), as shown by abrogation of apoptotic cell death and ROS production following pretreatment with the antioxidant N-acetylcysteine. These results suggest that DGG-300273 represents a promising investigational drug for the treatment of Wnt-associated cancer, thus warranting further characterization and study.
Assuntos
Neoplasias do Colo , beta Catenina , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Via de Sinalização WntRESUMO
SVCT2, Sodium-dependent Vitamin C Transporter 2, uniquely transports ascorbic acid (also known as vitamin C and ascorbate) into all types of cells. Vitamin C is an essential nutrient that must be obtained through the diet and plasma levels are tightly regulated by transporter activity. Vitamin C plays an important role in antioxidant defenses and is a cofactor for many enzymes that enable hormone synthesis, oxygen sensing, collagen synthesis and epigenetic pathways. Although SVCT2 has various functions, regulation of its expression/activity remains poorly understood. We found a p53-binding site, within the SVCT2 promoter, using a transcription factor binding-site prediction tool. In this study, we show that p53 can directly repress SVCT2 transcription by binding a proximal- (~-185 to -171 bp) and a distal- (~-1800 to -1787 bp) p53-responsive element (PRE), Chromatin immunoprecipitation assays showed that PRE-bound p53 interacts with the corepressor-histone deacetylase 3 (HDAC3), resulting in deacetylation of histones Ac-H4, at the proximal promoter, resulting in transcriptional silencing of SVCT2. Overall, our data suggests that p53 is a potent transcriptional repressor of SVCT2, a critical transporter of diet-derived ascorbic acid, across the plasma membranes of numerous essential tissue cell types.
Assuntos
Antioxidantes/metabolismo , Histona Desacetilases/genética , Transportadores de Sódio Acoplados à Vitamina C/genética , Proteína Supressora de Tumor p53/genética , Animais , Ácido Ascórbico/genética , Ácido Ascórbico/metabolismo , Sítios de Ligação/genética , Cromatina/genética , Fibroblastos , Células Hep G2 , Humanos , Camundongos , Ligação Proteica , Proteínas Repressoras/genética , Transportadores de Sódio Acoplados à Vitamina C/antagonistas & inibidoresRESUMO
Non-small lung cancer (NSCLC) is the most common cancer in the world. The epidermal growth factor receptor (EGFR) gene is mutated in approximately 10% of lung cancer cases in the US and 50% of lung cancer in Asia. The representative target therapeutic agent, erlotinib (EGFR tyrosine kinase inhibitor; EGFR TKI), is effective in inactivating EGFR in lung cancer patients. However, approximately 50-60% of patients are resistant to EGFR TKI. These populations are associated with the EGFR mutation. To overcome resistance to EGFR TKI, we discovered a JAK1 inhibitor, CJ14939. We investigated the efficacy of CJ14939 in human NSCLC cell lines in vitro and in vivo. Our results showed that CJ14939 induced the inhibition of cell growth. Moreover, we demonstrated that combination treatment with erlotinib and CJ14939 induced cell death in vitro and inhibited tumor growth in vivo. In addition, we confirmed the suppression of phosphorylated EGFR, JAK1, and Stat3 expression in erlotinib and CJ14939-treated human NSCLC cell lines. Our results provide evidence that JAK inhibition overcomes resistance to EGFR TKI in human NSCLCs.
Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cloridrato de Erlotinib/farmacologia , Janus Quinase 1/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Animais , Antineoplásicos/química , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/química , Feminino , Humanos , Janus Quinase 1/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Estrutura Molecular , Mutação , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
Inhibitor of apoptosis proteins (IAPs) are overexpressed in the majority of cancers and prevent apoptosis by inhibiting caspases. IAPs have therefore attracted considerable attention as potential targets for anticancer therapy. Here, we demonstrated that HM90822 (abbreviated HM822; a new synthetic IAP antagonist) induced apoptotic cell death via proteasome-dependent degradation of BIR2/3 domain-containing IAPs in human pancreatic cancer cells. HM822 inhibited the expression of XIAP and cIAP1/2 proteins in Panc-1 and BxPC-3 cells, which are sensitive to HM822. HM822 also induced IAP ubiquitination and promoted proteasome-dependent IAP degradation. However, cells expressing phospho-XIAP (Ser87) and AKT exhibited resistance to HM822. In other words, the overexpression of AKT-CA (constitutive active form for AKT) or AKT-WT induced resistance to HM822. In addition, in Panc-1 xenograft and orthotopic mouse models, we revealed that tumor growth was suppressed by the administration of HM822. Taken together, these results suggest that HM822 induces apoptosis through ubiquitin/proteasome-dependent degradation of BIR3 domain-containing IAPs. These findings suggest that phospho-XIAP and phospho-AKT may be used as biomarkers for predicting the efficacy of HM822 in pancreatic cancer patients.
Assuntos
Antineoplásicos/uso terapêutico , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carga Tumoral/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacosRESUMO
BACKGROUND: Mitogen-activated protein kinases (MEK 1/2) are central components of the RAS signalling pathway and are attractive targets for cancer therapy. These agents continue to be investigated in KRAS mutant colon cancer but are met with significant resistance. Clinical investigations have demonstrated that these strategies are not well tolerated by patients. METHODS: We investigated a biomarker of response for MEK inhibition in KRAS mutant colon cancers by LC-MS/MS analysis. We tested the MEK inhibitor in PIK3CA wild(wt) and mutant(mt) colon cancer cells. In addition, we tested the combinational effects of MEK and TNKS inhibitor in vitro and in vivo. RESULTS: We identified ß-catenin, a key mediator of the WNT pathway, in response to MEK inhibitor. MEK inhibition led to a decrease in ß-catenin in PIK3CA wt colon cancer cells but not in mt. Tumour regression was promoted by combination of MEK inhibition and NVP-TNS656, which targets the WNT pathway. Furthermore, inhibition of MEK promoted tumour regression in colon cancer patient-derived xenograft models expressing PIK3CA wt. CONCLUSIONS: We propose that inhibition of the WNT pathway, particularly ß-catenin, may bypass resistance to MEK inhibition in human PIK3CA mt colon cancer. Therefore, we suggest that ß-catenin is a potential predictive marker of MEK inhibitor resistance.
Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/genética , beta Catenina/metabolismo , Acetamidas/farmacologia , Animais , Biomarcadores Farmacológicos/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias do Colo/metabolismo , Farmacorresistência Viral , Humanos , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Pirimidinonas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/antagonistas & inibidoresRESUMO
Ionizing radiation is ubiquitous in the environment and can cause mutagenesis in living organisms. In this study, we examined the effects of neutron irradiation on tomato plants. Neutron irradiation decreased tomato germination rates, but most irradiated tomato plants did not show any significant phenotype. However, tomato mutants infected by Tomato yellow leaf curl virus (TYLCV) displayed resistance against TYLCV compared to the wild type (WT), which showed disease symptoms. RNA-Seq data demonstrated that the expression profiles of eight tomato mutants were significantly different from that of the WT. The transcriptomes obtained from presoaked seeds were highly altered compared to those of dry seeds. Increased irradiation time resulted in severe changes in the tomato transcriptome; however, different neutron irradiation intensities affected the expressions of different sets of genes. A high number of single-nucleotide polymorphisms in tomato transcriptomes suggest that neutron irradiation strongly impacts plant transcriptomes. The transition/transversion values among mutants were almost constant and were lower than that of the non-irradiated sample (WT), suggesting that neutron irradiation caused an effect. Taken together, this is the first report showing the effects of neutron irradiation on tomato plants by transcriptome analyses.
Assuntos
Begomovirus/patogenicidade , Perfilação da Expressão Gênica , Nêutrons , Solanum lycopersicum/genética , Solanum lycopersicum/virologia , Processamento Alternativo/genética , Processamento Alternativo/efeitos da radiação , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Germinação/efeitos da radiação , Solanum lycopersicum/efeitos da radiação , Mutação/genética , Doenças das Plantas/genética , Doenças das Plantas/virologia , Polimorfismo de Nucleotídeo Único/genética , Sementes/efeitos da radiação , Transcriptoma/genéticaRESUMO
Sphingosine-1-phosphate (S1P) regulates the proliferation of various cells and promotes the growth of cancer cells. Sphingosine kinase (SK), which transforms sphingosine into S1P, has two isotypes: SK1 and SK2. To date, both isotypes are known to be involved in the proliferation of cancer cells. PF-543, an SK1 inhibitor developed by Pfizer, strongly inhibits SK1. However, despite its strong SK1 inhibitory effect, PF-543 shows low anticancer activity in vitro. Therefore, additional biological evidence on the anticancer activity of SK1 inhibitor is required. The present study aimed to investigate the intracellular localization of PF-543 and identify its association with anticancer activity by introducing a fluoroprobe into PF-543. Boron-dipyrromethene (BODIPY)-introduced PF-543 has a similar SK1 inhibitory effect as PF-543. These results indicate that the introduction of BODIPY does not significantly affect the inhibitory effect of SK1. In confocal microscopy after BODIPY-PF-543 treatment, the compound was mainly located in the cytosol of the cells. This study demonstrated the possibility of introducing fluorescent material into an SK inhibitor and designing a synthesized compound that is permeable to cells while maintaining the SK inhibitory effect.
Assuntos
Compostos de Boro/química , Técnicas de Química Sintética , Pirrolidinas/química , Pirrolidinas/farmacologia , Sulfonas/química , Sulfonas/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Metanol , Estrutura Molecular , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Pirrolidinas/síntese química , Análise Espectral , Relação Estrutura-Atividade , Sulfonas/síntese químicaRESUMO
Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is a viral protein expressed in all EBV-infected cells that induces malignant transformation. EBNA1 is reported to contribute to tumor progression through an increase in reactive oxygen species via nicotinamide adenine dinucleotide phosphate oxidase. However, the underlying molecular mechanism of EBNA1-induced ROS accumulation in gastric cancer is poorly understood. Here, we demonstrated that miR34a regulation by EBNA1 determined cell fate in EBV-infected gastric cancer cells. ROS content and NOX2 expression were higher in EBNA1-expressing SNU719 cells than in EBNA1-nonexpressing SNU638 cells. Downregulation of NOX2 using siRNA technology in SNU719 cells decreased cell viability and ROS content. Regulation of EBNA1 expression in EBV-associated gastric cancers modulated NOX2 expression, ROS content and cell viability. We also showed that upregulation of NOX2 by EBNA1 was mediated by downregulating miRNA34a. Finally, overexpression of miR34a in EBNA1-expressing SNU719 cells induced typical apoptosis, suggesting that reactivation of miR34a in EBNA1-expressing gastric cancer cells could be a strategy for treatment of EBV-infected gastric cancer cells.
Assuntos
Sobrevivência Celular , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/fisiologia , MicroRNAs/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiologia , Linhagem Celular Tumoral , Humanos , Transdução de Sinais , Neoplasias Gástricas/patologiaRESUMO
The epithelial to mesenchymal transition (EMT), a hallmark of chronic kidney disease, is a key event in the conversion from tubular epithelial cells to myofibroblasts in renal fibrosis. Epstein-Barr virus (EBV) is a γ-herpes oncovirus associated with chronic kidney disease. However, the relationship between EBV and the EMT process in renal tubular epithelial cells is not well understood. Among EBV-latent genes, EBV-encoded latent membrane protein 1 (LMP1) induces EMT by regulating a variety of molecules in EBV-induced oncogenic transformation. In this study, we investigated EBV-encoded LMP1 and EMT process markers in human proximal tubule epithelial cell line HK-2. LMP1 overexpression induces cell morphological changes via the epithelial to mesenchymal process in HK-2 cells, and these changes accelerate cell proliferation, cell motility, and invasion. Furthermore, VSIG4 upregulation by EBV-LMP1 induced LMP1-mediated EMT, cell motility, and invasion. VSIG4 upregulation by LMP1 was regulated at the transcriptional level via the NF-kB signaling axis. These results suggest that EBV-encoded LMP1 regulates EMT through the NF-kB-VSIG4 axis in HK-2 cells, and VSIG4 is a potential target in EBV-induced chronic kidney diseases.
Assuntos
Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Túbulos Renais/metabolismo , NF-kappa B/metabolismo , Receptores de Complemento/genética , Proteínas da Matriz Viral/metabolismo , Animais , Células Cultivadas , Cães , Humanos , Túbulos Renais/citologia , Células Madin Darby de Rim Canino , Receptores de Complemento/metabolismoRESUMO
Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is an oncoviral protein that plays a pivotal role in EBV-induced oncogenic transformation. The function of LMP1 in EBV-induced oncogenesis has been well studied. However, the molecular mechanisms underlying LMP1 protein stability remain poorly understood. In this study, we found that ribosomal protein s27a (RPS27a) regulates LMP1 stability by a tandem affinity purification analysis. RPS27a interacts directly with LMP1 in vitro and in vivo. Furthermore, overexpression of RPS27a increases the half-life of LMP1 in 293T cells, whereas downregulation of RPS27a using lentiviral shRNA technology accelerates the decrease in LMP1 protein level in EBV-transformed B cells. We show that LMP1 ubiquitination via the proteasome is completely inhibited by overexpression of RPS27a. RPS27a also enhances LMP1-mediated proliferation and invasion, suggesting that RPS27a interacts with LMP1 and stabilizes it by suppressing proteasome-mediated ubiquitination. These results suggest that RSP27a could be a potential target in EBV-infected LMP1-positive cancer cells.
Assuntos
Transformação Celular Neoplásica/genética , Herpesvirus Humano 4/genética , Interações Hospedeiro-Patógeno , Proteínas Ribossômicas/genética , Ubiquitinas/genética , Proteínas da Matriz Viral/genética , Animais , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Cães , Regulação da Expressão Gênica , Células HEK293 , Meia-Vida , Herpesvirus Humano 4/crescimento & desenvolvimento , Herpesvirus Humano 4/metabolismo , Humanos , Células Madin Darby de Rim Canino , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Estabilidade Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/metabolismo , Transdução de Sinais , Ubiquitinação , Ubiquitinas/antagonistas & inibidores , Ubiquitinas/metabolismo , Proteínas da Matriz Viral/metabolismoRESUMO
YM155, which blocks the expression of survivin, a member of the inhibitor of apoptosis (IAP) family, induces cell death in a variety of cancer types, including prostate, bladder, breast, leukemia, and non-small lung cancer. However, the mechanism underlying gastric cancer susceptibility and resistance to YM155 is yet to be specified. Here, we demonstrate that cIAP1 stability dictates resistance to YM155 in human gastric cancer cells. Treatment of human gastric cancer cells with YM155 differentially induced cell death dependent on the stability of cIAP1 as well as survivin. Transfection with cIAP1 expression plasmids decreased cell sensitivity to YM155, whereas knockdown of endogenous cIAP1 using RNA interference enhanced sensitivity to YM155. In addition, double knockdown of survivin and cIAP1 significantly induced cell death in the YM155-resistant cell line, MKN45. We also showed that YM155 induced autoubiquitination and proteasome-dependent degradation of cIAP1. Surprisingly, survivin affected the stability of cIAP1 through binding, contributing to cell sensitivity to YM155. Thus, our findings reveal that YM155 sensitizes human gastric cancer cells to apoptotic cell death by degrading cIAP1, and furthermore, cIAP1 in gastric cancer cells may act as a PD marker for YM155 treatment.
Assuntos
Antineoplásicos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Imidazóis/farmacologia , Proteínas Inibidoras de Apoptose/genética , Naftoquinonas/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteólise , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Survivina , UbiquitinaçãoRESUMO
Pancreatic cancer is one of the most lethal cancers and remains a major unsolved health problem. Less than 20 % of patients are surgical candidates, and the median survival for non-resected patients is approximately 3 to 4 months. Despite the existence of many conventional cancer therapies, few targeted therapies have been developed for pancreatic cancer. Combination therapy using erlotinib and gemcitabine is an approved standard chemotherapy for advanced pancreatic cancer, but it has marginal therapeutic benefit. To try to improve the therapeutic outlook, we studied the efficacy of another combination treatment and the relevance to E-cadherin in human pancreatic cancer cells. We treated two human pancreatic cancer cell lines with the histone deacetylase inhibitor (HDACi) SAHA. Interestingly, in these Panc-1 and Capan1 cells, we observed that the expression levels of E-cadherin and phosphorylated EGFR were gradually upregulated after treatment with SAHA. Furthermore, these cells underwent induced cell death after exposure to the combination treatment of SAHA and erlotinib. In Panc-1 cells, overexpression of E-cadherin activated the phosphorylation of EGFR and increased the cell sensitivity to erlotinib. In Capan1 cells, knocking down E-cadherin decreased the expression of phosphorylated EGFR, and these cells did not respond to erlotinib. Therefore, we demonstrated the efficacy of the combined treatment with SAHA and erlotinib in human pancreatic cancer cells, and we determined that the increased efficacy was due, at least in part, to the effects of SAHA on the expression of E-cadherin. Our studies suggest that E-cadherin may be a potent biomarker for pancreatic cancer.
Assuntos
Caderinas/genética , Receptores ErbB/biossíntese , Cloridrato de Erlotinib/administração & dosagem , Inibidores de Histona Desacetilases/administração & dosagem , Ácidos Hidroxâmicos/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Caderinas/biossíntese , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Vorinostat , GencitabinaRESUMO
OBJECTIVE: To investigate the characteristics of recurrences that occurred 5 or more years after curative resection for gastric cancer. METHODS: We analyzed recurrences among 1,299 patients with gastric cancer who underwent curative operations at the Department of Surgery, Inje University Seoul Paik Hospital between September 1998 and December 2002. Recurrences were classified as within 2 years (early), 2-5 years (intermediate), and more than 5 years (late) after gastrectomy. The clinicopathologic findings of the patients with late recurrence were compared with those of patients in the other two recurrence groups, with special reference to the patterns of recurrence. Both univariate and multivariate analyses were performed, incorporating factors such as operation type, T-stage, N-stage, stage, lymphatic invasion, neural invasion, histology, tumor size, and recurrence site. RESULTS: At the time of last follow-up, recurrence occurred in 266 (20.5%) patients. Recurrence times were classified as <2 years (182 patients), 2-5 years (61 patients), or >5 years (23 patients). The late recurrence rate was 8.6%. The occurrence of recurrence >5 years after gastrectomy was significantly correlated with age, operation type, T-stage, N-stage, stage, lymphatic invasion, neural invasion, histology, tumor size, location and recurrence site (P<0.05). The main recurrence patterns in the 23 patients with late recurrence were locoregional metastasis (10 patients, 43.5%), peritoneal seeding (8 patients, 34.8%), hematogenous metastasis (2 patients, 8.7%), and multiple metastasis (3 patients, 13.0%). A multivariate analysis showed that larger tumor size and younger age were independent prognostic factors for late recurrence. Additionally, locoregional and peritoneal recurrences were significantly more common than hematogenous recurrences. CONCLUSIONS: Although late recurrence was uncommon, younger age and larger tumor size were associated with high risk. Follow-up surveillance is recommended for locoregional and peritoneal metastasis.
RESUMO
Deregulation of the PI3K-AKT/mTOR pathway due to mutation of the tumor suppressor gene PTEN frequently occurs in human prostate cancer and is therefore considered to be an attractive therapeutic target. Here, we investigated how the PTEN genotype affected the antitumor effect of NVP-BEZ235 in human prostate cancer cells. In this setting, NVP-BEZ235 induced cell death in a PTEN-independent manner. NVP-BEZ235 selectively induced apoptotic cell death in the prostate cancer cell line DU145, which harbors wild-type PTEN; however, in the PC3 cell line, which is PTEN-null, treatment with NVP-BEZ235 resulted in autophagic cell death. Consistently, NVP-BEZ235 treatment did not result in the cleavage of caspase-3; instead, it resulted in the conversion of LC3-I to LC3-II, indicating autophagic cell death; these results suggest that an alternate mechanism of cell death is induced by NVP-BEZ235 in PTEN-null prostate cancer cells. Based on our findings, we conclude that the PTEN/PI3K/Akt pathway is critical for prostate cancer survival, and targeting PI3K signaling by NVP-BEZ235 may be beneficial in the treatment of prostate cancer, independent of the PTEN genotype.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Imidazóis/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Neoplasias da Próstata/patologia , Quinolinas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Linhagem Celular Tumoral/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Genótipo , Humanos , Masculino , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
The MET proto-oncogene product, which is the receptor for hepatocyte growth factor (HGF), has been implicated in tumorigenesis and metastatic progression. Point mutations in MET lead to the aberrant activation of the receptor in many types of human malignancies, and the deregulated activity of MET has been correlated with tumor growth, invasion, and metastasis. MET has therefore attracted considerable attention as a potential target in anticancer therapy. Here, we report that a novel MET kinase inhibitor, NPS-1034, inhibits various constitutively active mutant forms of MET as well as HGF-activated wild-type MET. NPS-1034 inhibited the proliferation of cells expressing activated MET and promoted the regression of tumors formed from such cells in a mouse xenograft model through anti-angiogenic and pro-apoptotic actions. NPS-1034 also inhibited HGF-stimulated activation of MET signaling in the presence or absence of serum. Furthermore, when tested on 27 different MET variants, NPS-1034 inhibited 15 of the 17 MET variants that exhibited autophosphorylation with nanomolar potency; only the F1218I and M1149T variants were not inhibited by NPS-1034. Notably, NPS-1034 inhibited three MET variants that are resistant to the MET inhibitors SU11274, NVP-BVU972, and PHA665752. Together, these results suggest that NPS-1034 can be used as a potent therapeutic agent for human malignancies bearing MET point mutations or expressing activated MET.
Assuntos
Antineoplásicos/farmacologia , Compostos Heterocíclicos com 2 Anéis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Pirazóis/farmacologia , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Fator de Crescimento de Hepatócito/farmacologia , Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Humanos , Camundongos Mutantes , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Pirazóis/uso terapêutico , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: To compare the prevalence, location and magnitude of optic nerve head (ONH) OCT-detected, exposed neural canal (ENC), externally oblique choroidal border tissue (EOCBT) and exposed scleral flange (ESF) regions in 122 highly myopic (Hi-Myo) versus 362 nonhighly myopic healthy (Non-Hi-Myo-Healthy) eyes. DESIGN: Cross-sectional study. METHODS: After OCT radial B-scan, ONH imaging, Bruch's membrane opening (BMO), the anterior scleral canal opening (ASCO), and the scleral flange opening (SFO) were manually segmented in each B-scan and projected to BMO reference plane. The direction and magnitude of BMO/ASCO offset and BMO/SFO offset as well as the location and magnitude of ENC, EOCBT and ESF regions, perineural canal (pNC) retinal nerve fiber layer thickness (RNFLT) and pNC choroidal thickness (CT) were calculated within 30° sectors relative to the Foveal-BMO (FoBMO) axis. Hi-ESF eyes were defined to be those with an ESF region ≥100 µms in at least 1 sector. RESULTS: Hi-Myo eyes more frequently demonstrated Hi-ESF regions (87/122) than Non-Hi-myo-Healthy eyes (73/362) and contained significantly larger ENC, EOCBT, and ESF regions (P < .001) which were greatest in magnitude and prevalence within the inferior-temporal FoBMO sectors where Hi-Myo pNC-RNFLT and pNCCT were thinnest. BMO/ASCO offset and the BMO/SFO offset were both significantly increased (P < .001) in the Hi-Myo eyes, with the latter demonstrating a greater increase. CONCLUSIONS: ENC region tissue remodeling that includes the scleral flange is enhanced in Hi-Myo compared to Non-Hi-Myo-Healthy eyes. Longitudinal studies are necessary to determine whether the presence of an ENC region influences ONH susceptibility to aging and/or glaucoma.
Assuntos
Miopia , Disco Óptico , Humanos , Disco Óptico/anatomia & histologia , Tomografia de Coerência Óptica/métodos , Tubo Neural , Estudos Transversais , Miopia/diagnóstico , Lâmina Basilar da Corioide/anatomia & histologia , Pressão IntraocularRESUMO
The development of first-generation immune-checkpoint inhibitors targeting PD-1/PD-L1 and CTLA-4 ushered in a new era in anticancer therapy. Although immune-checkpoint blockade therapies have shown clinical success, a substantial number of patients yet fail to benefit. Many studies are under way to discover next-generation immunotherapeutic targets. Immunoglobulin superfamily member 1 (IGSF1) is a membrane glycoprotein proposed to regulate thyroid function. Despite containing 12 immunoglobin domains, a possible role for IGSF1, in immune response, remains unknown. Here, our studies revealed that IGSF1 is predominantly expressed in tumors but not normal tissues, and increased expression is observed in PD-L1low non-small cell lung cancer (NSCLC) cells as compared with PD-L1high cells. Subsequently, we developed and characterized an IGSF1-specific human monoclonal antibody, WM-A1, that effectively promoted antitumor immunity and overcame the limitations of first-generation immune-checkpoint inhibitors, likely via a distinct mechanism of action. We further demonstrated high WM-A1 efficacy in humanized peripheral blood mononuclear cells (PBMC), and syngeneic mouse models, finding additive efficacy in combination with an anti-PD-1 (a well-characterized checkpoint inhibitor). These findings support IGSF1 as an immune target that might complement existing cancer immunotherapeutics.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Imunoglobulinas , Neoplasias Pulmonares , Proteínas de Membrana , Animais , Humanos , Camundongos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antígeno B7-H1 , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoglobulinas/metabolismo , Imunoterapia , Leucócitos Mononucleares , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismoRESUMO
Members of the RAF family (ARAF, BRAF, and CRAF/RAF-1) are involved in a variety of cellular activities, including growth, survival, differentiation, and transformation. An oncogene encodes BRAF, the function of which is linked to MEK activation. BRAF is the most effective RAF kinase in terms of induction of MEK/ERK activity. However, the mechanisms involved in BRAF regulation remain unclear. In the present work, we used a tandem affinity purification approach to show that RNF149 (RING finger protein 149) interacts with wild-type BRAF. The latter protein is a RING domain-containing E3 ubiquitin ligase involved in control of gene transcription, translation, cytoskeletal organization, cell adhesion, and epithelial development. We showed that RNF149 bound directly to the C-terminal kinase-containing domain of wild-type BRAF and induced ubiquitination, followed by proteasome-dependent degradation, of the latter protein. Functionally, RNF149 attenuated the increase in cell growth induced by wild-type BRAF. However, RNF149 did not bind to mutant BRAF or induce ubiquitination thereof. Thus, we show that RNF149 is an E3 ubiquitin ligase active on wild-type BRAF.
Assuntos
Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Células HCT116 , Células HEK293 , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas B-raf/genética , Interferência de RNA , Sinvastatina/farmacologia , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/efeitos dos fármacosRESUMO
OBJECTIVE: The blood-brain barrier (BBB) is an obstacle for molecules to pass through from blood to the brain. Focused ultrasound is a new method which temporarily opens the BBB, which makes pharmaceutical delivery or removal of neurodegenerative proteins possible. This study was demonstrated to review our BBB opening procedure with magnetic resonance guided images and find specific patterns in the BBB opening. METHODS: In this study, we reviewed the procedures and results of two clinical studies on BBB opening using focused ultrasound regarding its safety and clinical efficacy. Magnetic resonance images were also reviewed to discover any specific findings. RESULTS: Two clinical trials showed clinical benefits. All clinical trials demonstrated safe BBB opening, with no specific side effects. Magnetic resonance imaging showed temporary T1 contrast enhancement in the sonication area, verifying the BBB opening. Several low-signal intensity spots were observed in the T2 susceptibility-weighted angiography images, which were also reversible and temporary. Although these spots can be considered as microbleeding, evidence suggests these are not ordinary microbleeding but an indicator for adequate BBB opening. CONCLUSION: Magnetic resonance images proved safe and efficient BBB opening in humans, using focused ultrasound.
RESUMO
OBJECTIVE: Stereotactic radiosurgery (SRS) is emerging as a treatment option for cavernous sinus dural arteriovenous fistula (CS dAVF); it is less invasive and has a lower complication rate than conventional surgeries. However, little is known regarding the advantages and limitations of SRS compared to those of endovascular treatment (EVT). The aim of this study was to compare the efficacy and safety between EVT and SRS for treatment of CS dAVF. METHODS: Between January 2011 and April 2021, a total of 86 consecutive patients diagnosed with CS dAVF were treated with EVT or SRS. Among them, 8 patients with ophthalmological emergency and 8 without follow-up data at ≥ 12 months were excluded. During the same period, no neurological deficit due to intracranial hemorrhage or seizure was noted in any of the patients. Ultimately, 70 patients (EVT 33, SRS 37) were included in this study. Demographic characteristics, initial clinical presentations, clinical outcomes, and radiological findings were retrospectively reviewed and compared. Procedure-related complications were also assessed after the treatments. RESULTS: The patients' baseline characteristics (except conjunctival symptoms) and angiographic features of CS dAVF were not significantly different between the EVT and SRS groups. Conjunctival symptoms were more frequently noted in the EVT than in the SRS group (69.7% vs 40.5%, p = 0.015). After EVT, initial complete obliteration was achieved in 20 cases (60.6%). Complete obliteration was achieved at 6 months in 86.4% of cases with EVT and in 77.8% of those treated with SRS (p = 0.507), and at 12 months in 86.4% cases with EVT and in 94.4% of those treated with SRS (p = 0.357). Worsening of symptoms developed at 1 month in 24.2% of cases with EVT and in 5.4% of those treated with SRS (p = 0.038); at 6 months in 22.6% of cases with EVT and in 10.8% of those treated with SRS; and at 12 months in 30.0% of cases with EVT and in 13.5% of those treated with SRS (p = 0.099). The angioarchitecture of CS dAVF did not affect angiographic obliteration after SRS. Procedure-related morbidity and mortality occurred more frequently in the EVT than in the SRS group (27.3% vs 8.1%, p = 0.034). CONCLUSIONS: Both EVT and SRS were effective for the treatment of CS dAVF without ophthalmological emergency. However, procedure-related morbidity and mortality was less frequent in SRS than in EVT, and consequently SRS may be more advantageous in terms of safety.