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1.
Hepatology ; 67(1): 188-203, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28802060

RESUMEN

Cancer cells display altered glucose metabolism characterized by a preference for aerobic glycolysis. The aerobic glycolytic phenotype of hepatocellular carcinoma (HCC) is often correlated with tumor progression and poorer clinical outcomes. However, the issue of whether glycolytic metabolism influences metastasis in HCC remains unclear. In the current study, we showed that knockdown of taurine up-regulated gene 1 (TUG1) induces marked inhibition of cell migration, invasion, and glycolysis through suppression of microRNA (miR)-455-3p. MiR-455-3p, which is transcriptionally repressed by p21, directly targets the 3' untranslated region of adenosine monophosphate-activated protein kinase subunit beta 2 (AMPKß2). The TUG1/miR-455-3p/AMPKß2 axis regulates cell growth, metastasis, and glycolysis through regulation of hexokinase 2 (HK2). TUG1 is clearly associated with HK2 overexpression and unfavorable prognosis in HCC patients. CONCLUSION: Our data collectively highlight that novel regulatory associations among TUG1, miR-455-3p, AMPKß2, and HK2 are an important determinant of glycolytic metabolism and metastasis in HCC cells and support the potential utility of targeting TUG1/HK2 as a therapeutic strategy for HCC. (Hepatology 2018;67:188-203).


Asunto(s)
Carcinoma Hepatocelular/genética , Regulación Neoplásica de la Expresión Génica/genética , Glucólisis/genética , Neoplasias Hepáticas/genética , ARN Largo no Codificante/genética , Biopsia con Aguja , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/patología , Masculino , MicroARNs/genética , Metástasis de la Neoplasia/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Transducción de Señal/efectos de los fármacos , Taurina/farmacología , Regulación hacia Arriba
2.
BMC Cancer ; 19(1): 176, 2019 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-30808421

RESUMEN

BACKGROUND: Zoledronic acid (ZA), a nitrogen-containing bisphosphonate, inhibits osteoclastogenesis. Emerging evidence suggests that ZA has anti-tumor and anti-metastatic properties for breast cancer cells. In a mouse model of ZA-related osteonecrosis of the jaw, ZA administration was found to suppress regulatory T-cells (Tregs) function. Our previous reports also demonstrated ZA acted as an immune modulator to block Tregs. Manipulation of Tregs represents a new strategy for cancer treatment. However, the relationship among ZA, Tregs, and cancer cells remains unclear. In this study, we investigated the effects of ZA on the interaction of breast cancer cells and Tregs. METHODS: The anti-tumor effect of ZA on triple negative breast cancer cell lines were validated by XTT, wound healing and apoptosis analysis. A flow cytometry-based assay was used to analyze the immunosuppressive effect of Tregs treated with media conditioned by breast cancer cells, and a transwell assay was used to evaluate the chemotactic migration of Tregs. Differential gene expression profile on MDA-MB-231 treated with ZA (25 µM) was analyzed by. microarrays to describe the molecular basis of actions of ZA for possible direct anti-tumor effects. Enzyme-linked immunosorbent assays and quantitative real-time PCR were used to investigate the effect of ZA on the expression of cytokines/factors by breast cancer cells. RESULTS: ZA was found to inhibit the proliferation and migration of breast cancer cells. Media conditioned by the MDA-MB-231 cells promoted the expansion, chemotactic migration, and immunosuppressive activity of Tregs, and these effects were attenuated in a dose-dependent manner by ZA treatment, and the attenuation was due to reduced expression of selected breast cancer cell factors (CCL2, CCL5, and IDO). CONCLUSIONS: ZA can significantly affect the interaction between breast cancer cells and Tregs. Our findings indicate that ZA is a potential therapeutic agent that can be used to reduce cancer aggressiveness by abolishing the supportive role of Tregs.


Asunto(s)
Factores Inmunológicos/farmacología , Linfocitos T Reguladores/inmunología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Ácido Zoledrónico/farmacología , Comunicación Celular , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Quimiocina CCL2/metabolismo , Quimiocina CCL5/metabolismo , Femenino , Perfilación de la Expresión Génica , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Linfocitos T Reguladores/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/inmunología , Microambiente Tumoral
3.
BMC Immunol ; 17(1): 45, 2016 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-27887569

RESUMEN

BACKGROUND: CD4+CD25+ regulatory T (Treg) cells suppress tumor immunity by inhibiting immune cells. Manipulation of Treg cells represents a new strategy for cancer treatment. Zoledronic acid (ZA), a nitrogen-containing bisphosphonate, inhibits the expression of receptor activator of nuclear factor kappa-B ligand (RANKL) on osteoblasts to inhibit osteoclastogenesis. In a mouse model of bisphosphonate-related osteonecrosis of the jaw, administration of ZA suppressed Treg-cell activity and activated inflammatory Th17 cells. However, the interaction between ZA and Treg cells remained unclear. This study investigated the immune modulation of Treg cells by ZA. METHODS: Flow cytometry was used to analyze the phenotypic and immunosuppressive characteristics of Treg cells treated with ZA. Chemotactic migration was evaluated using transwell assays. Quantitative real-time PCR (qRT-PCR) was used to investigate the effect of ZA on the expression of suppressive molecules by Treg cells. RESULTS: Proliferation of isolated Treg cells in culture was inhibited by ZA, although ZA did not induce apoptosis. qRT-PCR and flow cytometry showed that ZA significantly downregulated the expression of CCR4, CTLA4, PD-1 and RANKL on Treg cells. Chemotactic migration and immunosuppressive functions were also significantly attenuated in Treg cells pretreated with ZA, and these effects were dose-dependent. Co-culture with Treg cells significantly increased the migration rate of breast cancer cells, while pretreatment of Treg cells with ZA attenuated this effect. CONCLUSIONS: Our findings demonstrated that ZA acted as an immune modulator by significantly inhibiting the expansion, migration, immunosuppressive function and pro-metastatic ability of Treg cells. Immunomodulation of Treg cells by ZA represents a new strategy for cancer therapy.


Asunto(s)
Neoplasias de la Mama/inmunología , Vacunas contra el Cáncer/inmunología , Difosfonatos/farmacología , Imidazoles/farmacología , Factores Inmunológicos/farmacología , Inmunoterapia/métodos , Osteogénesis , Linfocitos T Reguladores/inmunología , Células Th17/inmunología , Neoplasias de la Mama/tratamiento farmacológico , Antígenos CD4/metabolismo , Movimiento Celular , Células Cultivadas , Técnicas de Cocultivo , Difosfonatos/uso terapéutico , Femenino , Humanos , Imidazoles/uso terapéutico , Factores Inmunológicos/uso terapéutico , Inmunoterapia/tendencias , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Activación de Linfocitos , FN-kappa B/metabolismo , Ligando RANK/metabolismo , Transducción de Señal , Linfocitos T Reguladores/efectos de los fármacos , Ácido Zoledrónico
4.
Int J Cancer ; 137(1): 37-49, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25430639

RESUMEN

The thyroid hormone, 3,3',5-triiodo-l-thyronine (T3 ), mediates several physiological processes, including embryonic development, cellular differentiation, metabolism and regulation of cell proliferation. Thyroid hormone (T3 ) and its receptor (TR) are involved in metabolism and growth. In addition to their developmental and metabolic functions, TRs play a tumor suppressor role, and therefore, their aberrant expression can lead to tumor transformation. Aberrant epigenetic silencing of tumor suppressor genes promotes cancer progression. The epigenetic regulator, Ubiquitin-like with PHD and ring finger domains 1 (UHRF1), is overexpressed in various cancers. In our study, we demonstrated that T3 negatively regulates UHRF1 expression, both in vitro and in vivo. Our results further indicate that UHRF1 regulation by T3 is indirect and mediated by Sp1. Sp1-binding elements of UHRF1 were identified at positions -664/-505 of the promoter region using the luciferase and chromatin immunoprecipitation assays. Notably, UHRF1 and Sp1 levels were elevated in subgroups of hepatocellular carcinoma patients and inversely correlated with TRα1 expression. Knockdown of UHRF1 expression should therefore provide a means to inhibit hepatoma cell proliferation. Expression of UHRF1 was downregulated by TRs, in turn, relieving silencing of the UHRF1 target gene, p21. Based on the collective findings, we propose that T3 /TR signaling induces hepatoma cell growth inhibition via UHRF1 repression.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/genética , Proliferación Celular/efectos de los fármacos , Neoplasias Hepáticas/patología , Receptores de Hormona Tiroidea/metabolismo , Triyodotironina/farmacología , Animales , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Regiones Promotoras Genéticas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factor de Transcripción Sp1/metabolismo , Ubiquitina-Proteína Ligasas
5.
J Hepatol ; 62(6): 1328-40, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25617495

RESUMEN

BACKGROUND & AIMS: Thyroid hormone (T3) and its receptor (TR) are involved in cell growth and cancer progression. Although deregulation of microRNA (miRNA) expression has been detected in many tumor types, the mechanisms underlying functional impairment and specific involvement of miRNAs in tumor metastasis remain unclear. In the current study, we aimed to elucidate the involvement of deregulated miRNA-130b (miR-130b) and its target genes mediated by T3/TR in cancer progression. METHODS: Quantitative reverse transcription-PCR, luciferase and chromatin immunoprecipitation assays were performed to identify the miR-130b transcript and the mechanisms implicated in its regulation. The effects of miR-130b on hepatocellular carcinoma (HCC) invasion were further examined in vitro and in vivo. Clinical correlations among miR-130b, TRs and interferon regulatory factor 1 (IRF1) were examined in HCC samples using Spearman correlation analysis. RESULTS: Our experiments disclosed negative regulation of miR-130b expression by T3/TR. Overexpression of miR-130b led to marked inhibition of cell migration and invasion, which was mediated via suppression of IRF1. Cell migration ability was promoted by T3, but partially suppressed upon miR-130b overexpression. Furthermore, miR-130b suppressed expression of epithelial-mesenchymal transition (EMT)-related genes, matrix metalloproteinase-9, phosphorylated mammalian target of rapamycin (mTOR), p-ERK1/2, p-AKT and p-signal transducer and activator of transcription (STAT)-3. Notably, miR-130b was downregulated in hepatoma samples and its expression patterns were inversely correlated with those of TRα1 and IRF1. CONCLUSIONS: Our data collectively highlight a novel pathway interlinking T3/TR, miR-130b, IRF1, the EMT-related genes, p-mTOR, p-STAT3 and the p-AKT cascade, which regulates the motility and invasion of hepatoma cells.


Asunto(s)
Movimiento Celular/genética , Movimiento Celular/fisiología , MicroARNs/genética , MicroARNs/metabolismo , Triyodotironina/metabolismo , Anciano , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Regulación hacia Abajo , Transición Epitelial-Mesenquimal , Femenino , Células Hep G2 , Humanos , Factor 1 Regulador del Interferón/genética , Factor 1 Regulador del Interferón/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Invasividad Neoplásica/fisiopatología , Receptores de Hormona Tiroidea/metabolismo , Transducción de Señal
6.
J Nutr Biochem ; 121: 109438, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37666476

RESUMEN

Combination therapies to induce mixed-type cell death and synthetic lethality have the potential to overcome drug resistance in cancer. In this study, we demonstrated that the curcumin-enhanced cytotoxicity of cisplatin/carboplatin in combination with gemcitabine was associated with Aurora A suppression-mediated G2/M arrest, and thus apoptosis, as well as MEK/ERK-mediated autophagy in human bladder cancer cells. Animal study data confirmed that curcumin combined with cisplatin/gemcitabine reduced tumorigenesis of xenograft in mice and this phenomenon was associated with elevated expressions of p-ERK and reduced p-Aurora A in tumors. Gene analyses using data repositories further revealed that reduced Aurora A expression alone did not significantly elevate the sensitivity of human bladder carcinoma cells to these anticancer drugs. Unlike other major cancer types, human bladder urothelial carcinoma tissue coexpressed higher AURKA and lower MAP1LC3B than normal tissue, and reduced Aurora A and induction of autophagy have been clinically associated with a better prognosis in patients with early but not advanced stage bladder cancer. Therefore, our results suggest that treatment strategies can utilize the synthetic lethal pair to concurrently suppress oncogenic Aurora A and induce autophagy by coadministrating curcumin with anticancer drugs for early-stage bladder cancer with high expression of Aurora A.

7.
Oncogene ; 41(2): 159-172, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34716430

RESUMEN

Pseudogenes are generally considered "junk" DNA or "genomic fossils" generated during the evolution process that lack biological activity. However, accumulating reports indicate that pseudogenes have biological functions critical for cancer development. Experiments from the current study showed marked overexpression of the cytidine monophospho-N-acetylneuraminic acid hydroxylase pseudogene (CMAHP) in gastric cancer, which was associated with poor overall survival. However, the mechanisms underlying the activity of CMAHP in tumor development are largely unknown. Gene Set Enrichment Analysis (GSEA) revealed that CMAHP-correlated genes are significantly involved in epithelial-mesenchymal transition (EMT) and angiogenesis. Functional studies further confirmed that CMAHP mediates metastasis and angiogenesis in vitro and in vivo. Furthermore, CMAHP promoted cancer cell migration, invasion, and metastasis through Snail overexpression, which decreased ubiquitination mediated by NF-κB signaling. Angiogenesis is known to be induced by granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation. CMAHP increased GM-CSF transactivation via promoting direct binding of c-Jun to the -1981/-1975 region of the GM-CSF promoter. Notably, CMAHP interacts with Histone H1.4 promoting histone acetylation to enhance c-Jun and RelA (p65) expression. Our collective findings provide novel evidence that CMAHP contributes to tumor progression and modulates metastasis and angiogenesis in gastric cancer.


Asunto(s)
Inductores de la Angiogénesis/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Neoplasias Gástricas/genética , Ubiquitinación/efectos de los fármacos , Inductores de la Angiogénesis/farmacología , Línea Celular Tumoral , Humanos , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Análisis de Supervivencia
8.
Theranostics ; 9(8): 2361-2379, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31149049

RESUMEN

Background & Aims: Hepatocellular carcinoma (HCC) is among the leading causes of cancer deaths worldwide. Many studies indicate that disruption of cellular thyroid hormone signaling promotes HCC progression. However, the mechanisms underlying the regulation of genes downstream of thyroid hormone actions in HCC have remained elusive. In the current study, we identified NUPR1 (nuclear protein-1), a stress-induced protein that overexpresses in various neoplasia, is upregulated by triiodothyronine/thyroid hormone receptor (T3/TR) signaling and aimed to elucidate its role in angiogenesis in cancer progression. Methods: Quantitative reverse transcription-PCR, luciferase promoter and chromatin immunoprecipitation assays were performed to identify the NUPR1 regulatory mechanism by T3/TR. In vitro and In vivo vascular formations were performed to detect the angiogenic function of NUPR1. Human angiogenesis arrays were performed to identify the downstream angiogenic pathway. The sorafenib resistant ability of TR/NUPR1 was further examined in vitro and in vivo. Clinical relevance of TR, NUPR1 and platelet-derived growth factor A (PDGFA) were investigate in HCC samples using qRT-PCR and western blot. Results: Our experiments disclosed positive regulation of NUPR1 expression by T3/TR through direct binding to the -2066 to -1910 region of the NUPR1 promoter. Elevated NUPR1 and TR expression link to poor survival in clinical HCC specimens. An analysis of clinicopathological parameters showed that expression of NUPR1 is associated with vascular invasion and pathology stage. Functional studies revealed that NUPR1 induced endothelial cell angiogenesis in vitro and in vivo. Using a human angiogenesis array, we identified PDGFA as a target of NUPR1 in the downstream angiogenic pathway. NUPR1 induced transcription of PDGFA through direct binding to the corresponding promoter region, and inhibition of the PDGFA signaling pathway impaired angiogenesis in human umbilical vein endothelial cells (HUVECs). Notably, the angiogenic effects of NUPR1/PDGFA were mediated by the MEK/ERK signaling pathway. TR/NUPR1 expression increased cell viability and resistance to sorafenib treatment. Moreover NUPR1 expression was positively correlated with TRα, TRß, and PDGFA expression. Conclusions: We propose that the T3/TR/NUPR1/PDGFA/MEK/ERK axis has a vital role in hepatocarcinogenesis and suggest NUPR1 as a potential therapeutic target in HCC.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Carcinoma Hepatocelular/fisiopatología , Neoplasias Hepáticas/fisiopatología , Proteínas de Neoplasias/biosíntesis , Neovascularización Patológica , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Triyodotironina/metabolismo , Animales , Línea Celular Tumoral , Perfilación de la Expresión Génica , Humanos , Immunoblotting , Inmunoprecipitación , Ratones Endogámicos BALB C , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Hormona Tiroidea/metabolismo , Transducción de Señal
9.
Neoplasia ; 20(1): 57-68, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29195126

RESUMEN

Thyroid hormone, 3,3',5-triiodo-l-thyronine (T3), mediates several physiological processes, including embryonic development, cellular differentiation and cell proliferation, via binding to its nuclear thyroid receptors (TR). Previous microarray and Chromatin immunoprecipitation (ChIP)-on-ChIP analyses have revealed that interferon-stimulated gene 20 kDa (ISG20), an exoribonuclease involved in the antiviral function of interferon, is up-regulated by T3 in HepG2-TR cells. However, the underlying mechanisms of ISG20 action in tumor progression remain unknown to date. Here, we verified induction of ISG20 mRNA and protein expression by T3 in HepG2-TR cells. Based on the ChIP-on-ChIP database, potential thyroid hormone responsive element of the ISG20 promoter region was predicted, and the result confirmed with the ChIP assay. Functional assays showed that forced expression of ISG20 leads to significant promotion of metastasis and angiogenesis, both in vitro and in vivo. Furthermore, the angiogenic-related protein, interleukin-8 (IL-8), was up-regulated through a T3-mediated increase in ISG20, as determined using a human angiogenesis array kit. Induction of IL-8 signaling activated the p-JAK2/p-STAT3 pathway, in turn, leading to promotion of tumor metastasis and angiogenesis. Furthermore, ISG20 overexpression in hepatocellular carcinoma (HCC) specimens was positively correlated with clinical parameters, including vascular invasion, α-fetoprotein and tumor size. Higher ISG20 expression was significantly correlated with poorer recurrence-free survival in HCC patients. Our results collectively indicate higher TR-dependent expression of ISG20 in a subset of HCC, supporting an oncogenic role in HCC progression.


Asunto(s)
Exonucleasas/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Hormonas Tiroideas/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Exonucleasas/metabolismo , Exorribonucleasas , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Técnicas de Inactivación de Genes , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Transducción de Señal
10.
Endocr Relat Cancer ; 25(12): 967-979, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30400024

RESUMEN

Thyroid hormone (T3) and its receptor (TR) are involved in cancer progression. While deregulation of long non-coding RNA (lncRNA) expression has been detected in many tumor types, the mechanisms underlying specific involvement of lncRNAs in tumorigenicity remain unclear. Experiments from the current study revealed negative regulation of BC200 expression by T3/TR. BC200 was highly expressed in hepatocellular carcinoma (HCC) and effective as an independent prognostic marker. BC200 promoted cell growth and tumor sphere formation, which was mediated via regulation of cell cycle-related genes and stemness markers. Moreover, BC200 protected cyclin E2 mRNA from degradation. Cell growth ability was repressed by T3, but partially enhanced upon BC200 overexpression. Mechanistically, BC200 directly interacted with cyclin E2 and promoted CDK2-cyclin E2 complex formation. Upregulation of cell cycle-related genes in hepatoma samples was positively correlated with BC200 expression. Our collective findings support the utility of a potential therapeutic strategy involving targeting of BC200 for the treatment of HCC.


Asunto(s)
Carcinogénesis/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , ARN Largo no Codificante/metabolismo , Hormonas Tiroideas/metabolismo , Anciano , Animales , Línea Celular Tumoral , Quinasa 2 Dependiente de la Ciclina/metabolismo , Ciclinas/metabolismo , Femenino , Humanos , Masculino , Ratones Desnudos , Persona de Mediana Edad , Receptores de Hormona Tiroidea/metabolismo
11.
Protein Sci ; 14(9): 2228-35, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16081647

RESUMEN

Transmissible spongiform encephalopathies (TSEs) are believed to be caused by an unconventional infectious agent, the prion protein. The pathogenic and infectious form of prion protein, PrPSc, is able to aggregate and form amyloid fibrils, very stable and resistant to most disinfecting processes and common proteases. Under specific conditions, PrPSc in bovine spongiform encephalopathy (BSE) brain tissue was found degradable by a bacterial keratinase and some other proteases. Since this disease-causing prion is infectious and dangerous to work with, a model or surrogate protein that is safe is needed for the in vitro degradation study. Here a nonpathogenic yeast prion-like protein, Sup35NM, cloned and overexpressed in E. coli, was purified and characterized for this purpose. Aggregation and deaggregation of Sup35NM were examined by electron microscopy, gel electrophoresis, Congo red binding, fluorescence, and Western blotting. The degradation of Sup35NM aggregates by keratinase and proteinase K under various conditions was studied and compared. These results will be of value in understanding the mechanism and optimization of the degradation process.


Asunto(s)
Endopeptidasa K/metabolismo , Péptido Hidrolasas/metabolismo , Priones/química , Priones/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Secuencia de Aminoácidos , Western Blotting , Rojo Congo/metabolismo , Escherichia coli/genética , Fluorescencia , Microscopía Electrónica/métodos , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/metabolismo , Factores de Terminación de Péptidos , Priones/aislamiento & purificación , Proteínas de Saccharomyces cerevisiae/aislamiento & purificación , Temperatura , Factores de Tiempo
12.
Oncotarget ; 6(17): 15050-64, 2015 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-25940797

RESUMEN

The thyroid hormone, 3,3',5-triiodo-L-thyronine (T3), regulates cell growth, development and differentiation via interactions with thyroid hormone receptors (TR), but the mechanisms underlying T3-mediated modulation of cancer progression are currently unclear. Lipocalin 2 (LCN2), a tumor-associated protein, is overexpressed in a variety of cancer types. Oligonucleotide microarray, coupled with proteomic analysis, has revealed that LCN2 is positively regulated by T3/TR. However, the physiological role and pathway of T3-mediated regulation of LCN2 in hepatocellular carcinogenesis remain to be characterized. Upregulation of LCN2 after T3 stimulation was observed in a time- and dose-dependent manner. Additionally, TRE on the LCN2 promoter was identified at positions -1444/-1427. Overexpression of LCN2 enhanced tumor cell migration and invasion, and conversely, its knockdown suppressed migration and invasion, both in vitro and in vivo. LCN2-induced migration occurred through activation of the Met/FAK cascade. LCN2 was overexpressed in clinical hepatocellular carcinoma (HCC) patients, compared with normal subjects, and positively correlated with TRα levels. Both TRα and LCN2 showed similar expression patterns in relation to survival rate, tumor grade, tumor stage and vascular invasion. Our findings collectively support a potential role of T3/TR in cancer progression through regulation of LCN2 via the Met/FAK cascade. LCN2 may thus be effectively utilized as a novel marker and therapeutic target in HCC.


Asunto(s)
Proteínas de Fase Aguda/genética , Quinasa 1 de Adhesión Focal/genética , Lipocalinas/genética , Neoplasias Hepáticas/genética , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas/genética , Transducción de Señal/genética , Hormonas Tiroideas/metabolismo , Proteínas de Fase Aguda/metabolismo , Animales , Western Blotting , Línea Celular Tumoral , Movimiento Celular/genética , Quinasa 1 de Adhesión Focal/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Lipocalina 2 , Lipocalinas/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones SCID , Invasividad Neoplásica , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Receptores de Hormona Tiroidea/metabolismo , Elementos de Respuesta/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Hormonas Tiroideas/farmacología , Trasplante Heterólogo , Triyodotironina/metabolismo , Triyodotironina/farmacología
13.
Oncotarget ; 6(11): 9341-54, 2015 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-25823820

RESUMEN

Despite numerous investigations on metastasis, the determinants of metastatic processes remain unclear. We aimed to identify the metastasis-associated genes in hepatocellular carcinoma (HCC). Potent metastatic SK-hep-1 (SK) cells, designated 'SKM', were generated using Transwell assay followed by selection in a mouse model. Genes expressed differentially in SKM and SK cells were identified via microarray analyses. A small form of Neural precursor cell-expressed developmentally downregulated 4 (sNEDD4) was identified to be overexpressed in SKM cells, which was confirmed as a novel transcript using liquid chromatography-mass spectrometry. In clinical specimens, sNEDD4 was significantly overexpressed in tumors and serves as a poor prognostic factor for male patients with HCC (P = 0.035). Upon subcutaneous introduction of sNEDD4-overexpressing SK cells into flanks of nude mice, tumors grew faster than those of the control group. Furthermore, sNEDD4-mediated promotion of tumor metastasis was demonstrated in the orthotopic mouse model. Overexpression of sNEDD4 increased the invasive ability of SK cells through upregulation of matrix metalloproteinase 9 and inhibited serum deprivation-induced apoptosis via upregulation of myeloid cell leukemia 1. In conclusion, sNEDD4 is a novel metastasis-associated gene, which prevents apoptosis under nutrient restriction conditions. The present findings clearly support the prognostic potential of sNEDD4 for HCC.


Asunto(s)
Apoptosis/genética , Carcinoma Hepatocelular/patología , Complejos de Clasificación Endosomal Requeridos para el Transporte/fisiología , Neoplasias Hepáticas/patología , Ubiquitina-Proteína Ligasas/fisiología , Animales , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidad , Línea Celular Tumoral , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidad , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ratones SCID , Ubiquitina-Proteína Ligasas Nedd4 , Invasividad Neoplásica , Pronóstico , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiología , Ubiquitina-Proteína Ligasas/genética , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Protein Sci ; 11(3): 659-68, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11847288

RESUMEN

The two amino acid residues, Asp 99 and Asp 201, involved in the coordination of the two calcium atoms in the X-ray structure of bovine pancreatic (bp) DNase, were individually changed by site-directed mutagenesis. The two altered proteins, brDNase(D99A) and brDNase(D201A) were expressed in Escherichia coli and purified by anion exchange chromatography. Equilibrium dialysis showed that mutation destroyed one Ca(2+)-binding site each in brDNase(D99A) and brDNase(D201A). Compared with bpDNase, the Vmax value for brDNase(D99A) remained unchanged and that for brDNase(D201A) was decreased, whereas the K(m) values for the two variants were increased two- to threefold when the DNA hydrolytic hyperchromicity assay was used. Like bpDNase, brDNase(D99A) was able to make double scission on duplex DNA with Mg(2+) plus Ca(2+) and was effectively protected by Ca(2+) from the trypsin inactivation. But under the same conditions, brDNase(D201A) lost the double-scission ability and was not protected by Ca(2+). Nevertheless, the two variant proteins retained the characteristics of the Ca(2+)-induced conformational changes and the Ca(2+) protection against the beta-mercaptoethanol disruption of the essential disulfide bond, suggesting that other weaker Ca(2+)-binding sites not found in the X-ray structure were responsible for these properties. Therefore, the two structural calcium atoms are not for maintaining the overall conformation of the active DNase, as it has been indicated in the X-ray analysis, but rather play the role in the fine-tuning of the DNase activity.


Asunto(s)
Calcio/química , Desoxirribonucleasa I/química , Páncreas/enzimología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Calcio/metabolismo , Bovinos , Desoxirribonucleasa I/genética , Desoxirribonucleasa I/metabolismo , Desoxirribonucleasas/metabolismo , Escherichia coli , Humanos , Cinética , Metales/farmacología , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Páncreas/química , Plásmidos/metabolismo , Unión Proteica , Proteínas Recombinantes/química , Termodinámica , Tripsina/metabolismo
15.
Protein Sci ; 13(4): 875-83, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15044724

RESUMEN

We characterized the biochemical functions of the small nonessential (C101-C104) and the large essential (C173-C209) disulfides in bovine pancreatic (bp) DNase using alanine mutants [brDNase(C101A)] and [brDNase(C173A) and brDNase(C209A)], respectively. We also characterized the effects of an additional third disulfide [brDNase(F192C/A217C)]. Without the Ca(2+) protection, bpDNase and brDNase(C101A) were readily inactivated by trypsin, whereas brDNase(F192C/A217C) remained active. With Ca(2+), all forms of DNase, except for brDNase(C101A), were protected against trypsin. All forms of DNase, after being dissolved in 6 M guanidine-HCl, were fully reactivated by diluting into a Ca(2+)-containing buffer. However, when diluted into a Ca(2+)-free buffer, bpDNase and brDNase(C101A) remained inactive, but 60% of the bpDNase activity was restored with brDNase(F192C/A217C). When heated, bpDNase was inactivated at a transition temperature of 65 degrees C, brDNase(C101A) at 60 degrees C, and brDNase(F192C/A217C) at 73 degrees C, indicating that the small disulfide, albeit not essential for activity, is important for the structural integrity, and that the introduction of a third disulfide can further stabilize the enzyme. When pellets of brDNase(C173A) and brDNase(C209A) in inclusion bodies were dissolved in 6 M guanidine-HCl and then diluted into a Ca(2+)-containing buffer, 10%-18% of the bpDNase activity was restored, suggesting that the "essential" disulfide is not absolutely crucial for enzymatic catalysis. Owing to the structure-based sequence alignment revealing homology between the "nonessential" disulfide of bpDNase and the active-site motif of thioredoxin, we measured 39% of the thioredoxin-like activity for bpDNase based on the rate of insulin precipitation (DeltaA650nm/min). Thus, the disulfides in bpDNase not only play the role of stabilizing the protein molecule but also may engage in biological functions such as the disulfide/dithiol exchange reaction.


Asunto(s)
Desoxirribonucleasa I/química , Desoxirribonucleasa I/genética , Disulfuros/química , Sustitución de Aminoácidos/genética , Animales , Sitios de Unión , Calcio/química , Bovinos , Guanidina/química , Insulina/química , Desnaturalización Proteica , Homología Estructural de Proteína , Tiorredoxinas/química , Tripsina/química
16.
Cancer Lett ; 351(2): 222-31, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-24933454

RESUMEN

MicroRNAs (miRNAs) play an important role to contribute carcinogenesis. The aim of the current study was to identify useful biomarkers from miRNAs. Differential miRNA profiles were analyzed using the miRNA qRT-PCR-based assay. Two of the most upregulated miRNAs were selected and validated. The miR-196a/-196b levels were significantly increased in gastric cancer (GC) tissues (n=109). Overexpression of miR-196a/-196b was significantly associated with tumor progression and poorer 5-year survival outcomes. Overexpression of miR-196a/-196b enhances GC cell migration and invasion. Further, radixin was identified as a target gene of miR-196a/-196b. Elevated miR-196a/-196b expression in GC cells led to reduced radixin protein levels and vice versa. Notably, an inverse correlation between miR-196a/-196b and radixin mRNA and protein expression was observed in GC tissues with in situ hybridization and immunohistochemistry analyses. Together, miR-196a/-196b inhibitory oligonucleotides or overexpression of the radixin may thus have therapeutic potential in suppressing GC metastasis.


Asunto(s)
Proteínas del Citoesqueleto/genética , Regulación Neoplásica de la Expresión Génica , Proteínas de la Membrana/genética , MicroARNs/genética , Neoplasias Gástricas/genética , Anciano , Línea Celular Tumoral , Movimiento Celular/genética , Proteínas del Citoesqueleto/biosíntesis , Regulación hacia Abajo , Femenino , Genes Supresores de Tumor , Humanos , Inmunohistoquímica , Masculino , Proteínas de la Membrana/biosíntesis , MicroARNs/biosíntesis , MicroARNs/metabolismo , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Transfección , Células Tumorales Cultivadas , Regulación hacia Arriba
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