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1.
Gastroenterology ; 160(4): 1194-1207.e28, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32946903

RESUMO

BACKGROUND & AIMS: Squalene epoxidase (SQLE), a rate-limiting enzyme in cholesterol biosynthesis, is suggested as a proto-oncogene. Paradoxically, SQLE is degraded by excess cholesterol, and low SQLE is associated with aggressive colorectal cancer (CRC). Therefore, we studied the functional consequences of SQLE reduction in CRC progression. METHODS: Gene and protein expression data and clinical features of CRCs were obtained from public databases and 293 human tissues, analyzed by immunohistochemistry. In vitro studies showed underlying mechanisms of CRC progression mediated by SQLE reduction. Mice were fed a 2% high-cholesterol or a control diet before and after cecum implantation of SQLE genetic knockdown/control CRC cells. Metastatic dissemination and circulating cancer stem cells were demonstrated by in vivo tracking and flow cytometry analysis, respectively. RESULTS: In vitro studies showed that SQLE reduction helped cancer cells overcome constraints by inducing the epithelial-mesenchymal transition required to generate cancer stem cells. Surprisingly, SQLE interacted with GSK3ß and p53. Active GSK3ß contributes to the stability of SQLE, thereby increasing cell cholesterol content, whereas SQLE depletion disrupted the GSK3ß/p53 complex, resulting in a metastatic phenotype. This was confirmed in a spontaneous CRC metastasis mice model, where SQLE reduction, by a high-cholesterol regimen or genetic knockdown, strikingly promoted CRC aggressiveness through the production of migratory cancer stem cells. CONCLUSIONS: We showed that SQLE reduction caused by cholesterol accumulation aggravates CRC progression via the activation of the ß-catenin oncogenic pathway and deactivation of the p53 tumor suppressor pathway. Our findings provide new insights into the link between cholesterol and CRC, identifying SQLE as a key regulator in CRC aggressiveness and a prognostic biomarker.


Assuntos
Colesterol/metabolismo , Neoplasias Colorretais/patologia , Esqualeno Mono-Oxigenase/metabolismo , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Colo/patologia , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Mucosa Intestinal/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/patologia , Oxirredução , Proto-Oncogene Mas , Reto/patologia , Esqualeno Mono-Oxigenase/genética , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem , beta Catenina/metabolismo
2.
Genomics ; 113(6): 4136-4148, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34715294

RESUMO

Hereditary Spastic Paraplegias (HSP) are a group of rare inherited neurological disorders characterized by progressive loss of corticospinal motor-tract function. Numerous patients with HSP remain undiagnosed despite screening for known genetic causes of HSP. Therefore, identification of novel genetic variations related to HSP is needed. In this study, we identified 88 genetic variants in 54 genes from whole-exome data of 82 clinically well-defined Korean HSP families. Fifty-six percent were known HSP genes, and 44% were composed of putative candidate HSP genes involved in the HSPome and originally reported neuron-related genes, not previously diagnosed in HSP patients. Their inheritance modes were 39, de novo; 33, autosomal dominant; and 10, autosomal recessive. Notably, ALDH18A1 showed the second highest frequency. Fourteen known HSP genes were firstly reported in Koreans, with some of their variants being predictive of HSP-causing protein malfunction. SPAST and REEP1 mutants with unknown function induced neurite abnormality. Further, 54 HSP-related genes were closely linked to the HSP progression-related network. Additionally, the genetic spectrum and variation of known HSP genes differed across ethnic groups. These results expand the genetic spectrum for HSP and may contribute to the accurate diagnosis and treatment for rare HSP.


Assuntos
Paraplegia Espástica Hereditária , Povo Asiático , Exoma , Humanos , Proteínas de Membrana Transportadoras/genética , Mutação , República da Coreia , Paraplegia Espástica Hereditária/diagnóstico , Paraplegia Espástica Hereditária/genética , Espastina/genética
3.
Mol Carcinog ; 55(4): 387-96, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25647515

RESUMO

TRAIL (TNF-related apoptosis inducing ligand) is a promising anti-cancer drug target that selectively induces apoptosis in cancer cells. However, many cancer cells are resistant to TRAIL-induced apoptosis. Therefore, reversing TRAIL resistance is an important step for the development of effective TRAIL-based anti-cancer therapies. We previously reported that knockdown of the TOR signaling pathway regulator-like (TIPRL) protein caused TRAIL-induced apoptosis by activation of the MKK7-c-Jun N-terminal Kinase (JNK) pathway through disruption of the MKK7-TIPRL interaction. Here, we identified Taraxacum officinale F.H. Wigg (TO) as a novel TRAIL sensitizer from a set of 500 natural products using an ELISA system and validated its activity by GST pull-down analysis. Furthermore, combination treatment of Huh7 cells with TRAIL and TO resulted in TRAIL-induced apoptosis mediated through inhibition of the MKK7-TIPRL interaction and subsequent activation of MKK7-JNK phosphorylation. Interestingly, HPLC analysis identified chicoric acid as a major component of the TO extract, and combination treatment with chicoric acid and TRAIL induced TRAIL-induced cell apoptosis via JNK activation due to inhibition of the MKK7-TIPRL interaction. Our results suggest that TO plays an important role in TRAIL-induced apoptosis, and further functional studies are warranted to confirm the importance of TO as a novel TRAIL sensitizer for cancer therapy. © 2015 Wiley Periodicals, Inc.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Taraxacum/química , Antineoplásicos Fitogênicos/química , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , MAP Quinase Quinase 7/metabolismo , Mapas de Interação de Proteínas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
4.
Aging Cell ; : e14152, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517197

RESUMO

As people age, the risk and progression of colorectal cancer (CRC), along with cholesterol levels, tend to increase. Nevertheless, epidemiological studies on serum lipids and CRC have produced conflicting results. We previously demonstrated that the reduction of squalene epoxidase (SQLE) due to accumulated cholesterol within cells accelerates CRC progression through the activation of the ß-catenin pathway. This study aimed to investigate the mechanism by which age-related cholesterol accumulation within tissue accelerates CRC progression and to assess the clinical significance of SQLE in older individuals with elevated CRC risk. Using machine learning-based digital image analysis with fluorescence-immunohistochemistry, we assessed SQLE, GSK3ßpS9 (GSK3ß activity inhibition through serine 9 phosphorylation at GSK3ß), p53 wild-type (p53WT), and p53 mutant (p53MT) levels in CRC tissues. Our analysis revealed a significant reduction in SQLE, p53WT, and p53MT and increase in GSK3ßpS9 levels, all associated with the substantial accumulation of intra-tissue cholesterol in aged CRCs. Cox analysis underscored the significant influence of SQLE on overall survival and progression-free survival in grade 2-3 CRC patients aged over 50. SQLE and GSK3ßpS9 consistently exhibited outstanding prognostic and diagnostic performance, particularly in older individuals. Furthermore, combining SQLE with p53WT, p53MT, and GSK3ßpS9 demonstrated a robust diagnostic ability in the older population. In conclusion, we have identified that individuals aged over 50 face an increased risk of CRC progression due to aging-linked cholesterol accumulation within tissue and the subsequent reduction in SQLE levels. This study also provides valuable biomarkers, including SQLE and GSK3ßpS9, for older patients at elevated risk of CRC.

5.
Br J Pharmacol ; 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745399

RESUMO

BACKGROUND AND PURPOSE: Chitinase-3-like 1 (CHI3L1) causes skin inflammation in the progression of atopic dermatitis. We investigated if anti-CHI3L1 antibody could prevent the development of atopic dermatitis and its mechanisms of action. EXPERIMENTAL APPROACH: The effect of CHI3L1 antibody on phthalic anhydride-induced atopic dermatitis animal model and in vitro reconstructed human skin (RHS) model were investigated. Expression and release of atopic dermatitis-related cytokines were determined using an enzyme-linked immunosorbent assay, and RT-qPCR, STAT3 and CXCL8 signalling were measured by western blotting. KEY RESULTS: Anti-CHI3L1 antibody suppressed phthalic anhydride-induced epidermal thickening, clinical score, IgE level and infiltration of inflammatory cells, and reduced phthalic anhydride-induced inflammatory cytokines concentration. In addition, CHI3L1 antibody treatment inhibited the expression of STAT3 activity in phthalic anhydride-treated skin. It was also confirmed that CHI3L1 antibody treatment alleviated atopic dermatitis-related inflammation in the RHS model. The inhibitory effects of CHI3L1 antibody was similar or more effective compared with that of the IL-4 antibody. We further found that CHI3L1 is associated with CXCL8 by protein-association network analysis. siRNA of CHI3L1 blocked the mRNA levels of CHI3L1, IL-1ß, IL-4, CXCL8, TSLP, and the expression of CHI3L1 and p-STAT, and the level of CXCL8, whereas recombinant level of CXCL8 was elevated. Moreover, siRNA of STAT3 reduced the mRNA level of these cytokines. CHI3L1 and p-STAT3 expression correlated with the reduced CXCL8 level in the RHS in vitro model. CONCLUSION AND IMPLICATIONS: Our data demonstrated that CHI3L1 antibody could be a promising effective therapeutic drug for atopic dermatitis.

6.
Mol Neurobiol ; 59(3): 1398-1418, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34997539

RESUMO

TREX1 is an exonuclease that degrades extranuclear DNA species in mammalian cells. Herein, we show a novel mechanism by which TREX1 interacts with the BiP/GRP78 and TREX1 deficiency triggers ER stress through the accumulation of single-stranded DNA and activates unfolded protein response (UPR) signaling via the disruption of the TREX1-BiP/GRP78 interaction. In TREX1 knockdown cells, the activation of ER stress signaling disrupted ER Ca2+ homeostasis via the ERO1α-IP3R1-CaMKII pathway, leading to neuronal cell death. Moreover, TREX1 knockdown dysregulated the Golgi-microtubule network through Golgi fragmentation and decreased Ac-α-tubulin levels, contributing to neuronal injury. These alterations were also observed in neuronal cells harboring a TREX1 mutation (V91M) that has been identified in hereditary spastic paraplegia (HSP) patients in Korea. Notably, this mutation leads to defects in the TREX1-BiP/GRP78 interaction and mislocalization of TREX1 from the ER and possible disruption of the Golgi-microtubule network. In summary, the current study reveals TREX1 as a novel regulator of the BiP/GRP78 interaction and shows that TREX1 deficiency promotes ER stress-mediated neuronal cell death, which indicates that TREX1 may hold promise as a therapeutic target for neurodegenerative diseases such as HSP.


Assuntos
Retículo Endoplasmático , Proteínas de Choque Térmico , Animais , Morte Celular , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Homeostase , Humanos , Mamíferos/metabolismo
7.
J Microencapsul ; 28(3): 220-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21425947

RESUMO

When an inflammatory stimulus is given, vascular endothelial cells express various cell adhesion molecules including the vascular cell adhesion molecule (VCAM)-1. In this study, the possibility of specifically delivering anti-inflammatory drugs to activated endothelial cells by utilizing VCAM-1 as a target receptor was explored by loading celecoxib, a selective cyclooxygenase-2 inhibitor, into liposomes coupled to the Fab' fragment against VCAM-1. Anti-VCAM-1-Fab'-conjugated liposomes were prepared by forming an amide linkage between amino groups of Fab' and the carboxylic group of glutaryl-N-phosphatidylethanolamine in liposomes using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as a cross-linker in the presence of sulpho-N-hydroxysuccinimide. The coupling of Fab' to phospholipids constituting liposomes was confirmed by SDS-PAGE analysis. Under our optimized conjugation conditions, 130.0 µg Fab' was coupled to 1 µmol liposomes. Immunoblotting analysis showed that VCAM-1 protein expression could be induced by incubating human umbilical vein endothelial cells (HUVEC) with TNF-α. Confocal laser microsopy analysis revealed that Fab' conjugation to liposomes selectively increased liposomal uptake in TNF-α-pre-stimulated (VCAM-1-expressed) HUVECs, but not in cells without VCAM-1 expression. The concentration of celecoxib loaded in Fab'-conjugated liposomes was 281.1 ± 29 µg/mL, suggesting that liposomal loading also helped to overcome the limitations in celecoxib administration caused by its poor water solubility. Celecoxib loaded in Fab'-conjugated liposomes inhibited prostaglandin E2 (PGE2) production induced by TNF-α-pre-stimulation more efficiently than when loaded in conventional liposomes. Therefore, Fab'-conjugated liposomes served as a drug delivery system with dual functions: targeted delivery and solubilizing capacity.


Assuntos
Células Endoteliais/citologia , Fragmentos Fab das Imunoglobulinas/química , Pirazóis , Sulfonamidas , Veias Umbilicais/citologia , Molécula 1 de Adesão de Célula Vascular/química , Celecoxib , Células Cultivadas , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacocinética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Lipossomos , Pirazóis/química , Pirazóis/farmacocinética , Pirazóis/farmacologia , Solubilidade , Sulfonamidas/química , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Veias Umbilicais/metabolismo , Molécula 1 de Adesão de Célula Vascular/biossíntese , Molécula 1 de Adesão de Célula Vascular/imunologia , Água/química
8.
Cancers (Basel) ; 13(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208132

RESUMO

Recently, we reported the involvement of TIPRL/LC3/CD133 in liver cancer aggressiveness. This study assessed the human TOR signaling regulator (TIPRL)/microtubule-associated light chain 3 (LC3)/prominin-1 (CD133)/cluster of differentiation 44 (CD44) as potential diagnostic and prognostic biomarkers for early liver cancer. For the assessment, we stained tissues of human liver disease/cancer with antibodies against TIPRL/LC3/CD133/CD44/CD46, followed by confocal observation. The roles of TIPRL/LC3/CD133/CD44/CD46 in liver normal and cancer cell lines were determined by in vitro studies. We analyzed the prognostic and diagnostic potentials of TIPRL/LC3/CD133/CD44/CD46 using the receiver-operating characteristic curve, a Kaplan-Meier and uni-/multi-Cox analyses. TIPRL and LC3 were upregulated in tissues of HCCs and adult hepatocytes-derived liver diseases while downregulated in iCCA. Intriguingly, TIPRL levels were found to be critically associated with liver cancer patients' survivability, and TIPRL is the key player in liver cancer cell proliferation and viability via stemness and self-renewal induction. Furthermore, we demonstrate that TIPRL/LC3/CD133 have shown prominent efficiency for diagnosing patients with grade 1 iCCA. TIPRL/LC3/CD133/CD44 have also provided excellent potential for prognosticating patients with grade 1 iCCA and grade 1 HCCs, together with demonstrating that TIPRL/LC3/CD133/CD44 are, either individually or in conjunction, potential biomarkers for early liver cancer.

10.
Genet Test Mol Biomarkers ; 24(1): 54-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31829726

RESUMO

Aim: Lennox-Gastaut syndrome (LGS) is a severe type of childhood-onset epilepsy with multiple types of seizures, specific discharges on electroencephalography, and intellectual disability. However, LGS-related genes are largely unknown. To identify causative genes related to LGS, we collected and analyzed data from a three-generation Korean family in which one member had LGS and two had intellectual disability. Methods: Genomic DNAs were extracted from blood samples of all participants and used in whole-exome sequencing (WES). Genetic variants were detected by the Genome Analysis Toolkit and confirmed by Sanger sequencing. Variant pathogenicity was evaluated by prediction programs and the American College of Medical Genetics criteria. The LGS patient had generalized slow spike-and-wave discharges, multiple types of seizures, and developmental delay. Results: Analyses of the WES data from the family revealed a novel variant (c.1048G>A, p.Ala350Thr) in the IQ motif and Sec7 domain 2 (IQSEC2). This variant is within a highly evolutionarily conserved IQ-like motif, indicating a decrease in the calmodulin-binding capacity or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid transmission. The hemizygous variant in the male with LGS was a maternally inherited X-linked variant from the heterozygous maternal grandmother and mother, both of whom had intellectual disability. Conclusion: These findings indicate that the variant of IQSEC2 triggered both LGS and intellectual disability dependent on sex in this family. We report a novel X-linked inherited IQSEC2 variant for LGS and intellectual disability, which enhances the spectrum of variants in the IQ-like motif of IQSEC2.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Deficiência Intelectual/genética , Síndrome de Lennox-Gastaut/genética , Adulto , Criança , Epilepsia/genética , Família , Feminino , Genes Ligados ao Cromossomo X/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Masculino , Linhagem , República da Coreia , Sequenciamento do Exoma
11.
Front Genet ; 11: 590924, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33584793

RESUMO

Lennox-Gastaut syndrome (LGS) is a severe type of childhood-onset epilepsy characterized by multiple types of seizures, specific discharges on electroencephalography, and intellectual disability. Most patients with LGS do not respond well to drug treatment and show poor long-term prognosis. Approximately 30% of patients without brain abnormalities have unidentifiable causes. Therefore, accurate diagnosis and treatment of LGS remain challenging. To identify causative mutations of LGS, we analyzed the whole-exome sequencing data of 17 unrelated Korean families, including patients with LGS and LGS-like epilepsy without brain abnormalities, using the Genome Analysis Toolkit. We identified 14 mutations in 14 genes as causes of LGS or LGS-like epilepsy. 64 percent of the identified genes were reported as LGS or epilepsy-related genes. Many of these variations were novel and considered as pathogenic or likely pathogenic. Network analysis was performed to classify the identified genes into two network clusters: neuronal signal transmission or neuronal development. Additionally, knockdown of two candidate genes with insufficient evidence of neuronal functions, SLC25A39 and TBC1D8, decreased neurite outgrowth and the expression level of MAP2, a neuronal marker. These results expand the spectrum of genetic variations and may aid the diagnosis and management of individuals with LGS.

12.
Sci Rep ; 10(1): 21295, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277610

RESUMO

The coiled-coil domain containing 50 (CCDC50) protein is a phosphotyrosine-dependent signalling protein stimulated by epidermal growth factor. It is highly expressed in neuronal cells in the central nervous system; however, the roles of CCDC50 in neuronal development are largely unknown. In this study, we showed that the depletion of CCDC50-V2 impeded the neuronal development process, including arbor formation, spine density development, and axonal outgrowth, in primary neurons. Mechanistic studies revealed that CCDC50-V2 positively regulated the nerve growth factor receptor, while it downregulated the epidermal growth factor receptor pathway. Importantly, JNK/c-Jun activation was found to be induced by the CCDC50-V2 overexpression, in which the interaction between CCDC50-V2 and JNK2 was also observed. Overall, the present study demonstrates a novel mechanism of CCDC50 function in neuronal development and provides new insight into the link between CCDC50 function and the aetiology of neurological disorders.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Crescimento Neuronal , Animais , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Células HEK293 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Transdução de Sinais
13.
Sci Rep ; 9(1): 16802, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727942

RESUMO

Studies have reported dysregulation of TIPRL, LC3 and CD133 in liver cancer tissues. However, their respective relationships to liver cancer and roles as biomarkers for prognosis and diagnosis of liver cancer have never been studied. Here we report that the level of TIPRL is significantly correlated with levels of LC3 (Spearman r = 0.9) and CD133 (r = 0.7) in liver cancer tissues. We observed significant upregulations of TIPRL, LC3 and CD133 in hepatocellular carcinomas (HCCs) compared with adjacent normal tissues. Importantly, TIPRL, tested among additional variables, showed a significant impact on the prognosis of HCC patients. TIPRL knockdown significantly reduced expressions of LC3, CD133, stemness-related genes, as well as viability and stemness of liver cancer cell-lines, which were promoted by ectopic TIPRL expression. Either alone or as a combination, TIPRL, LC3 and CD133 showed significant values of area under the curve (AUC) and sensitivity/specificity in early liver cancer tissues. Furthermore, the statistical association and the diagnostic efficacies of TIPRL, LC3 and CD133 in HCC tissues were confirmed in a different IHC cohort. This data demonstrates that the complex involvement of TIPRL/LC3/CD133 in liver cancer aggressiveness can together or individually serve as potential biomarkers for the early detection of liver cancer.


Assuntos
Antígeno AC133/metabolismo , Carcinoma Hepatocelular/diagnóstico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/diagnóstico , Proteínas Associadas aos Microtúbulos/metabolismo , Regulação para Cima , Antígeno AC133/genética , Área Sob a Curva , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Estudos de Coortes , Detecção Precoce de Câncer , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/genética , Células-Tronco Neoplásicas/metabolismo , Prognóstico
14.
Cell Death Dis ; 10(12): 959, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862913

RESUMO

Autophagy, an intracellular system of degrading damaged organelles and misfolded proteins, is essential for cancer cell survival. Despite the progress made towards understanding the mechanism, identification of novel autophagy regulators presents a major obstacle in developing anticancer therapies. Here, we examine the association between the TOR signaling pathway regulator-like (TIPRL) protein and autophagy in malignant transformation of tumors. We show that TIPRL upregulation in non-small cell lung cancer (NSCLC) potentiated autophagy activity and enabled autophagic clearance of metabolic and cellular stress, conferring a survival advantage to cancer cells. Importantly, the interaction of TIPRL with eukaryotic initiation factor 2α (eIF2α) led to eIF2α phosphorylation and activation of the eIF2α-ATF4 pathway, thereby inducing autophagy. Conversely, TIPRL depletion increased apoptosis by reducing autophagic clearance, which was markedly enhanced in TIPRL-depleted A549 xenografts treated with 2-deoxy-D-glucose. Overall, the study indicated that TIPRL is a potential regulator of autophagy and an important drug target for lung cancer therapy.


Assuntos
Fator 4 Ativador da Transcrição/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Fator de Iniciação 2 em Eucariotos/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Células A549 , Animais , Apoptose , Autofagia/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Sobrevivência Celular , Estresse do Retículo Endoplasmático , Feminino , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Fosforilação , Transdução de Sinais , Esferoides Celulares/patologia
15.
Oncotarget ; 8(68): 112610-112622, 2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29348850

RESUMO

Hepatocellular carcinoma (HCC) is one of the most malignant tumors. Although various treatments, such as surgery and chemotherapy, have been developed, a novel alternative therapeutic approach for HCC therapy is urgently needed. Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a promising anti-cancer agent, but many cancer cells are resistant to TRAIL-induced apoptosis. To help overcome TRAIL resistance in HCC cancer cells, we have identified novel chemical compounds that act as TRAIL sensitizers. We first identified the hit compound, TRT-0002, from a chemical library of 6,000 compounds using a previously developed high-throughput enzyme-linked immunosorbent assay (ELISA) screening system, which was based on the interaction of mitogen-activated protein kinase kinase 7 (MKK7) and TOR signaling pathway regulator-like (TIPRL) proteins and a cell viability assay. To increase the efficacy of this TRAIL sensitizer, we synthesized 280 analogs of TRT-0002 and finally identified two lead compounds (TRT-0029 and TRT-0173). Co-treating cultured Huh7 cells with either TRT-0029 or TRT-0173 and TRAIL resulted in TRAIL-induced apoptosis due to the inhibition of the MKK7-TIPRL interaction and subsequent phosphorylation of MKK7 and c-Jun N-terminal kinase (JNK). In vivo, injection of these compounds and TRAIL into HCC xenograft tumors resulted in tumor regression. Taken together, our results suggest that the identified lead compounds serve as TRAIL sensitizers and represent a novel strategy to overcome TRAIL resistance in HCC.

16.
Oncotarget ; 7(48): 79774-79786, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27806330

RESUMO

Tumor metastasis is the leading cause of cancer death. In the metastatic process, EMT is a unique phenotypic change that plays an important role in cell invasion and changes in cell morphology. Despite the clinical significance, the mechanism underlying tumor metastasis is still poorly understood. Here we report a novel mechanism by which secreted plasma glutamate carboxypeptidase(PGCP) negatively involves Wnt/ß-catenin signaling by DKK4 regulation in liver cancer metastasis. Pathway analysis of the RNA sequencing data showed that PGCP knockdown in liver cancer cell lines enriched the functions of cell migration, motility and mesenchymal cell differentiation. Depletion of PGCP promoted cell migration and invasion via activation of Wnt/ß-catenin signaling pathway components such as phospho-LRP6 and ß-catenin. Also, addition of DKK4 antagonized the Wnt/ß-catenin signaling cascade in a thyroxine (T4)-dependent manner. In an in vivo study, metastatic nodules were observed in the lungs of the mice after injection of shPGCP stable cell lines. Our findings suggest that PGCP negatively associates with Wnt/ß-catenin signaling during metastasis. Targeting this regulation may represent a novel and effective therapeutic option for liver cancer by preventing metastatic activity of primary tumor cells.


Assuntos
Carboxipeptidases/sangue , Movimento Celular , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Animais , Carboxipeptidases/antagonistas & inibidores , Carboxipeptidases/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , RNA Interferente Pequeno/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Oncol Rep ; 32(3): 1117-23, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24969837

RESUMO

Induction of apoptosis through activation of the TRAIL pathway is considered to be a promising anticancer strategy due to its ability to selectively induce apoptosis in cancer cells. However, the ability of cancer cells to acquire TRAIL resistance has limited the clinical translation of this approach. We previously reported that the TOR signaling pathway regulator-like (TIPRL) protein contributes to the resistance to TRAIL-induced apoptosis by inhibiting the MKK7-c-Jun N-terminal kinase (JNK) pathway via MKK7­TIPRL interaction. In the present study, we identified Tussilago farfara L. (TF) as a novel TRAIL sensitizer among 500 natural products using an ELISA system that specifically detects the MKK7-TIPRL interaction, and we validated candidates by GST-pull down assay. Co-treatment of Huh7 cells with TF and TRAIL induced apoptosis via inhibition of the MKK7-TIPRL interaction and an increase in MKK7/JNK phosphorylation. This is the first report to describe TF as a novel TRAIL sensitizer, unveiling a potentially novel therapeutic strategy in cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tussilago/química , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia
18.
Korean J Pediatr ; 55(9): 330-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23049590

RESUMO

PURPOSE: Fractional exhaled nitric oxide (FeNO) and forced expiratory flow between 25% and 75% of vital capacity (FEF(25-75)) are not included in routine monitoring of asthma control. We observed changes in FeNO level and FEF(25-75) after FeNO-based treatment with inhaled corticosteroid (ICS) in children with controlled asthma (CA). METHODS: We recruited 148 children with asthma (age, 8 to 16 years) who had maintained asthma control and normal forced expiratory volume in the first second (FEV(1)) without control medication for ≥3 months. Patients with FeNO levels >25 ppb were allocated to the ICS-treated (FeNO-based management) or untreated group (guideline-based management). Changes in spirometric values and FeNO levels from baseline were evaluated after 6 weeks. RESULTS: Ninety-three patients had FeNO levels >25 ppb. These patients had lower FEF(25-75)% predicted values than those with FeNO levels ≤25 ppb (P<0.01). After 6 weeks, the geometric mean (GM) FeNO level in the ICS-treated group was 45% lower than the baseline value, and the mean percent increase in FEF(25-75) was 18.% which was greater than that in other spirometric values. There was a negative correlation between percent changes in FEF(25-75) and FeNO (r=-0.368, P=0.001). In contrast, the GM FeNO and spirometric values were not significantly different from the baseline values in the untreated group. CONCLUSION: The anti-inflammatory treatment simultaneously improved the FeNO levels and FEF(25-75) in CA patients when their FeNO levels were >25 ppb.

19.
J Korean Soc Coloproctol ; 27(6): 303-14, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22259746

RESUMO

PURPOSE: A retrorectal developmental cyst (tailgut cyst, epidermoid cyst, dermoid cyst, teratoma, and duplication) is very rare disease, and the symptoms are not characteristic so that sometimes this disease is still misdiagnosed as a supralevator abscess or a complex anal fistula. We would like to present a clinical approach to this disease. METHODS: We retrospectively examined the charts of 15 patients who were treated for retrorectal cysts from January 2001 to November 2009. RESULTS: All 15 patients were female. The average age was 41 years (range, 21 to 60 years). Fourteen patients (93.3%) were symptomatic, and the most common symptom was anal pain or discomfort. Nine patients (60%) had more than one previous operation (range, 1 to 9 times) for a supralevator abscess, an anal fistula, etc. In 12 patients (80%), the diagnosis could be made by using the medical history and physical examination. Thirteen cysts (80%) were excised completely through the posterior approach. The average diameter of the cysts was 4.8 cm (range, 2 to 10 cm). Pathologic diagnoses were 8 tailgut cysts (53.3%), 5 epidermoid cysts (33.3%) and 2 dermoid cysts (13.3%). The average follow-up period was 18.3 months (range, 1 to 64 months). CONCLUSION: In our experience, high suspicion and physical examination are the most important diagnostic methods. If a female patient has a history of multiple perianal operations, a retrorectal bulging soft mass, a posterior anal dimple, and no conventional creamy foul odorous pus in drainage, the possibility of a retrorectal developmental cyst must be considered.

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