Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 128
Filter
Add more filters

Country/Region as subject
Affiliation country
Publication year range
1.
J Am Chem Soc ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38859621

ABSTRACT

Color encoding plays a crucial role in painting, digital photography, and spectral analysis. Achieving accurate, target-responsive color encoding at the molecular level has the potential to revolutionize scientific research and technological innovation, but significant challenges persist. Here, we propose a multibit DNA self-assembly system based on computer-aided design (CAD) technology, enabling accurate, target-responsive, amplified color encoding at the molecular level, termed fluorescence encoding (FLUCO). As a model, we establish a quaternary FLUCO system using four-bit DNA self-assembly, which can accurately encode 51 colors, presenting immense potential in applications such as spatial proteomic imaging and multitarget analysis. Notably, FLUCO enables the simultaneous imaging of multiple targets exceeding the limitations of channels using conventional imaging equipment, and marks the integration of computer science for molecular encoding and decoding. Overall, our work paves the way for target-responsive, controllable molecular encoding, facilitating spatial omics analysis, exfoliated cell analysis, and high-throughput liquid biopsy.

2.
Cancer Sci ; 113(7): 2258-2271, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35441753

ABSTRACT

IL-27 is an anti-inflammatory cytokine that triggers enhanced antitumor immunity, particularly cytotoxic T lymphocyte responses. In the present study, we sought to develop IL-27 into a therapeutic adjutant for adoptive T cell therapy using our well-established models. We have found that IL-27 directly improved the survival status and cytotoxicity of adoptive OT-1 CD8+ T cells in vitro and in vivo. Meanwhile, IL-27 treatment programs memory T cell differentiation in CD8+ T cells, characterized by upregulation of genes associated with T cell memory differentiation (T-bet, Eomes, Blimp1, and Ly6C). Additionally, we engineered the adoptive OT-1 CD8+ T cells to deliver IL-27. In mice, the established tumors treated with OT-1 CD8+ T-IL-27 were completely rejected, which demonstrated that IL-27 delivered via tumor antigen-specific T cells enhances adoptive T cells' cancer immunity. To our knowledge, this is the first application of CD8+ T cells as a vehicle to deliver IL-27 to treat tumors. Thus, this study demonstrates IL-27 is a feasible approach for enhancing CD8+ T cells' antitumor immunity and can be used as a therapeutic adjutant for T cell adoptive transfer to treat cancer.


Subject(s)
CD8-Positive T-Lymphocytes , Interleukin-27 , Animals , Cell Differentiation , Cell Line, Tumor , Cell Survival , Immunotherapy, Adoptive , Memory T Cells , Mice , Mice, Inbred C57BL
3.
J Sep Sci ; 45(15): 3054-3062, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35754361

ABSTRACT

Phosphorylation is one of the most important protein post-translational modifications, which possesses dramatic regulatory effects on the function of proteins. In consideration of the low abundance and low stoichiometry of phosphorylation and non-specific signal suppression, efficient capture of the phosphoproteins from complex biological samples is critical to meet the need for protein profiling. In this work, a facile preparation of titanium (IV)-immobilized O-phospho-L-tyrosine modified magnetic nanoparticles was developed for the enrichment of intact phosphoproteins. The prepared magnetic nanoparticles were characterized by various instruments and had a spherical shape with an average diameter of 300 nm. The adsorption isotherms were investigated and the maximum capacity for ß-casein was calculated to be 961.5 mg/g. Standard protein mixtures and biological samples (non-fat milk and human serum) were selected to test the enrichment performance. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis demonstrated the excellent enrichment performance with high selectivity. With the superparamagnetic property, titanium (IV)-immobilized O-phospho-L-tyrosine modified magnetic nanoparticles were convenient for the practical application and clinical promotion, thus having a promising prospect in the field of phosphoprotein research.


Subject(s)
Magnetite Nanoparticles , Nanoparticles , Caseins/analysis , Humans , Phosphopeptides , Phosphoproteins , Titanium , Tyrosine/analogs & derivatives
4.
Anal Bioanal Chem ; 413(11): 2893-2901, 2021 May.
Article in English | MEDLINE | ID: mdl-33704525

ABSTRACT

Selective separation and enrichment of phosphoproteins possess the distinct clinical and biological importance in the diagnosis, treatment, and management of several fatal human diseases. In this study, a facile synthesis of titanium(IV) ion-immobilized arsenate-modified poly(glycidyl methacrylate) microparticles (denoted as Ti4+-arsenate-PGMA-MPs) was developed for the efficient enrichment of intact phosphoproteins found in biologically complex protein samples. By virtue of the strong interaction between the titanium ions immobilized on the surface of Ti4+-arsenate-PGMA-MPs and phosphate groups of phosphoproteins, Ti4+-arsenate-PGMA-MPs had a high saturated adsorption capacity for phosphoproteins (901 mg/g for ß-casein), which was much higher than that of non-phosphoproteins (73.5 mg/g for BSA). Ti4+-arsenate-PGMA-MPs were characterized by SEM, TEM, and FT-IR, and the average particle diameter was about 2.5 µm with good dispersibility. Besides, the application of Ti4+-arsenate-PGMA-MPs in real biological samples was investigated by SDS-PAGE analysis, and the results showed that Ti4+-arsenate-PGMA-MPs were able to enrich phosphoproteins efficiently.


Subject(s)
Arsenates/chemistry , Epoxy Compounds/chemistry , Methacrylates/chemistry , Phosphoproteins/chemistry , Polymers/chemistry , Titanium/chemistry , Adsorption , Caseins/analysis , Cell Line , Electrophoresis, Polyacrylamide Gel , Humans , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Microspheres , Spectrum Analysis/methods , Thermodynamics
5.
Mol Cancer ; 19(1): 24, 2020 Feb 04.
Article in English | MEDLINE | ID: mdl-32019547

ABSTRACT

After the publication of this work [1], the authors noticed that the affiliations were incorrectly provided. Updated affiliation section is provided in this paper.

6.
Carcinogenesis ; 40(9): 1121-1131, 2019 Sep 18.
Article in English | MEDLINE | ID: mdl-30715269

ABSTRACT

Emerging studies have revealed that O-GlcNAcylation plays pivotal roles in the tumorigenesis of colorectal cancers (CRCs). However, the underlying mechanism still remains largely unknown. Here, we demonstrated that Yin Yang 1 (YY1) was O-GlcNAcylated by O-GlcNAc transferase (OGT) and O-GlcNAcylation of YY1 could increase the protein expression by enhancing its stability. O-GlcNAcylation facilitated transformative phenotypes of CRC cell in a YY1-dependent manner. Also, O-GlcNAcylation stimulates YY1-dependent transcriptional activity. Besides, we also identified the oncoproteins, SLC22A15 and AANAT, which were regulated by YY1 directly, are responsible for the YY1 stimulated tumorigenesis. Furthermore, we identified the main putative O-GlcNAc site of YY1 at Thr236, and mutating of this site decreased the pro-tumorigenic capacities of YY1. We concluded that O-GlcNAcylation of YY1 stimulates tumorigenesis in CRC cells by targeting SLC22A15 and AANAT, suggesting that YY1 O-GlcNAcylation might be a potential effective therapeutic target for treating CRC.

7.
Mol Cancer ; 18(1): 188, 2019 12 23.
Article in English | MEDLINE | ID: mdl-31870368

ABSTRACT

BACKGROUND: N6-Methyladenosine (m6A) modification has been implicated in many biological processes. It is important for the regulation of messenger RNA (mRNA) stability, splicing, and translation. However, its role in cancer has not been studied in detail. Here we investigated the biological role and underlying mechanism of m6A modification in hepatoblastoma (HB). METHODS: We used Reverse transcription quantitative real-time PCR (RT-qPCR) and Western blotting to determine the expression of m6A related factors. And we clarified the effects of these factors on HB cells using cell proliferation assay, colony formation, apoptotic assay. Then we investigated of methyltransferase-like 13 (METTL3) and its correlation with clinicopathological features and used xenograft experiment to check METTL3 effect in vivo. m6A-Seq was used to profiled m6A transcriptome-wide in hepatoblastoma tumor tissue and normal tissue. Finally, methylated RNA immunoprecipitation (MeRIP) assay, RNA remaining assay to perform the regulator mechanism of MEETL3 on the target CTNNB1 in HB. RESULTS: In this research, we discovered that m6A modifications are increased in hepatoblastoma, and METTL3 is the main factor involved with aberrant m6A modification. We also profiled m6A across the whole transcriptome in hepatoblastoma tumor tissues and normal tissues. Our findings suggest that m6A is highly expressed in hepatoblastoma tumors. Also, m6A is enriched not only around the stop codon, but also around the coding sequence (CDS) region. Gene ontology analysis indicates that m6A mRNA methylation contributes significantly to regulate the Wnt/ß-catenin pathway. Reduced m6A methylation can lead to a decrease in expression and stability of the CTNNB1. CONCLUSION: Overall our findings suggest enhanced m6A mRNA methylation as an oncogenic mechanism in hepatoblastoma, METTL3 is significantly up-regulated in HB and promotes HB development. And identify CTNNB1 as a regulator of METTL3 guided m6A modification in HB.

8.
J Cell Physiol ; 234(1): 606-618, 2018 01.
Article in English | MEDLINE | ID: mdl-30078215

ABSTRACT

Although it is generally accepted that diabetes is one of the most important risk factors for liver cancer, the underlying mechanism is still not well understood. The purpose of the current study is to further investigate how high concentrations of glucose (HG), a major symptom of diabetes, stimulate the development of liver malignancy. Using data mining, gap junction protein gamma 1 (GJC1) was identified as a critical proto-oncoprotein that is essential for the HG stimulation of proliferative capacity in liver cancer cells. Furthermore, enhanced transcriptional expression of GJC1 might occur after stimulation by HG. A transcription factor zinc finger protein 410 (APA1)-binding motif was found to be located at the -82 to -77 nt region within the GJC1 promoter. Without APA1, HG was unable to increase GJC1 expression. Interestingly, APA1, but not GJC1, can be O-GlcNAcylated in liver cancer cells. Moreover, O-GlcNAcylation is essential for HG-induced APA1 binding to the GJC1 promoter. Notably, global O-GlcNAcylation and expression of APA1 and GJC1 were highly elevated in liver cancer patients with diabetes compared to those in patients without diabetes. The HG-stimulated proliferative capacity was abolished upon decreasing O-GlcNAcylation, which could be reversed gradually by the simultaneous overexpression of APA1 and GJC1. Therefore, GJC1 could be a potential target for preventing liver cancer in patients with diabetes.


Subject(s)
Connexins/genetics , Diabetes Mellitus/genetics , Liver Neoplasms/genetics , Transcription Factors/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Proliferation/genetics , Diabetes Complications/genetics , Diabetes Complications/pathology , Diabetes Mellitus/metabolism , Diabetes Mellitus/pathology , Gene Expression Regulation, Neoplastic/drug effects , Glucose/pharmacology , Glycosylation/drug effects , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , N-Acetylglucosaminyltransferases/genetics , Promoter Regions, Genetic
9.
Biochem Biophys Res Commun ; 495(1): 1555-1561, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29217192

ABSTRACT

AMOT has been identified as a YAP interactor. However, how AMOT regulates YAP remains unclear and controversy. Here, we identified that besides YAP, AMOT was another Hippo signaling core factor which could be O-GlcNAcylated. Moreover, high glucose (HG) was able to enhance the expression and O-GlcNAcylation of AMOT. We also found that HG stimulated nuclear accumulation, transcription activity, interaction with transcription factor and transcription of target genes of YAP via AMOT, while AMOT acted as a suppressor of YAP in normal glucose level. Finally, we observed the upregulation and nuclear accumulation of AMOT and YAP in Streptozocin (STZ) induced high glucose mice. Collectively, we have uncovered that AMOT acts as a YAP stimulator in high glucose level. Targeting the aberrantly regulated core factors in Hippo pathway might be a more effective therapeutic approach for liver cancer associated with possibly diabetes.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Blood Glucose/metabolism , Diabetes Complications/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/etiology , Liver Neoplasms/metabolism , Microfilament Proteins/metabolism , Phosphoproteins/metabolism , Angiomotins , Animals , Cell Cycle Proteins , Cell Nucleus/metabolism , Diabetes Complications/pathology , Liver Neoplasms/pathology , Mice , YAP-Signaling Proteins
10.
J Cell Physiol ; 232(12): 3347-3359, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28063214

ABSTRACT

We previously reported that both the ubiquitin E3 ligases ßTrCP (beta-transducin repeat-containing E3 ubiquitin protein ligase) and Smurf1 (SMAD-specific E3 ubiquitin protein ligase 1) play similar antitumorigenic roles in liver cancer cells. However, whether and how they are reciprocally regulated remains elusive. Here, we show that ßTrCP interacts with Smurf1 through the 7 × tryptophan (W) aspartic acid (D)(WD) 40 and the region homologous to the E6-AP carboxyl terminus (HECT) domains, which are the E3 ligase domains of ßTrCP and Smurf1, respectively. The E3 ligase domains of ßTrCP and Smurf1 are also critical for maintaining the protein expressions of Smurf1 and ßTrCP. Moreover, a positive correlation between ßTrCP and Smurf1 was also revealed by tissue microarray analysis, indicating that this relationship might be important in liver cancer. Further, we found that Smurf1 increases the protein stability of ßTrCP, possibly by reducing autoubiquitination of ßTrCP, and vice versa. Interestingly, such effects depended on the presence of E3 ligase domains. Importantly, depletion of Smurf1- or ßTrCP-enhanced proliferative capacity of liver cancer cells could be partially reversed by overexpression of wild-type ßTrCP or Smurf1 but not their E3 ligase-dead mutants. Collectively, a reciprocal post-translational regulation between ßTrCP and Smurf1 has been uncovered in this study. Simultaneous enhancement of ßTrCP and Smurf1 functions might be helpful in the treatment of liver cancer.


Subject(s)
Cell Proliferation , Liver Neoplasms/metabolism , Ubiquitin-Protein Ligases/metabolism , beta-Transducin Repeat-Containing Proteins/metabolism , Cell Line, Tumor , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Protein Stability , Ubiquitin-Protein Ligases/genetics , beta-Transducin Repeat-Containing Proteins/genetics
11.
Biochem Biophys Res Commun ; 487(2): 433-437, 2017 05 27.
Article in English | MEDLINE | ID: mdl-28427939

ABSTRACT

The Wnt pathway is crucial for animal development, as well as tumor formation. Understanding the regulation of Wnt signaling will help to elucidate the mechanism of the cell cycle, cell differentiation and tumorigenesis. It is generally accepted that in response to Wnt signals, ß-catenin accumulates in the cytoplasm and is imported into the nucleus where it recruits LEF/TCF transcription factors to activate the expression of target genes. In this study, we report that human NRAGE, a neurotrophin receptor p75 (p75NTR) binding protein, markedly suppresses the expression of genes activated by the Wnt pathway. Consistent with this finding, loss of function of NRAGE by RNA interference (RNAi) activates the Wnt pathway. Moreover, NRAGE suppresses the induction of axis duplication by microinjected ß-catenin in Xenopus embryos. To our surprise, NRAGE induces nuclear localization of ß-catenin and increases its DNA binding ability. Further studies reveal that NRAGE leads to the modification of ß-catenin/Arm with O-linked beta-N-acetylglucosamine (O-GlcNAc), and failure of the association between ß-catenin/Arm and pygopus(pygo) protein, which is required for transcriptional activation of Wnt target genes. Therefore, our findings suggest a novel mechanism for regulating Wnt signaling.


Subject(s)
Acetylglucosamine/metabolism , Antigens, Neoplasm/metabolism , DNA/metabolism , N-Acetylglucosaminyltransferases/metabolism , Neoplasm Proteins/metabolism , Wnt Signaling Pathway/physiology , beta Catenin/metabolism , Acylation/physiology , Armadillo Domain Proteins/metabolism , Cell Nucleus/metabolism , Down-Regulation/physiology , HEK293 Cells , Humans
12.
Tumour Biol ; 39(6): 1010428317708532, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28653878

ABSTRACT

Sirtuin 6, a member of sirtuin family, is generally regarded as a tumor suppressor as it participates in suppressing hypoxia-inducible factor 1α and MYC transcription activity by deacetylating H3K9 (histone H3 lysine 9) and H3K56 (histone H3 lysine) at promoters of target genes, leading to the aerobic glycolysis inhibition and cell growth suppression. However, its expression has recently been reported to be highly elevated in a series of tumors, including prostate cancer, breast cancer, and non-small cell lung cancer, indicating that sirtuin 6 plays dual roles in tumorigenicity in a cell/tumor type-specific manner. To our knowledge, the biological roles of sirtuin 6 in esophageal cancer cells have still been underestimated. In the study, data from quantitative reverse transcriptase polymerase chain reaction-based assays and immunohistochemical assays revealed that sirtuin 6 was remarkably overexpressed in esophageal squamous tumor tissues. Moreover, its upregulation was closely related with clinical features, such as gender, pathology, tumor-node-metastasis, and cell differentiation. Subsequently, the biological tests showed that it promoted cell proliferation and induced the expression of Bcl2, a key anti-apoptotic factor, in esophageal carcinoma cells. Moreover, using the ratio of LC3II/I, a widely recognized autophagy biomarker, we showed that it apparently induced cell autophagy, which was further confirmed by the autophagy flux assays. In addition, results from western blotting assays and immunoprecipitation assays displayed that sirtuin 6 specifically interacted with ULK1 and positively regulated its activity by inhibiting its upstream factor mammalian target of rapamycin activity. In summary, our studies shed insights into the crucial functions of sirtuin 6 in esophageal carcinoma cells and provide evidence supporting sirtuin 6-based personalized therapies in esophageal carcinoma cell patients.


Subject(s)
Autophagy-Related Protein-1 Homolog/genetics , Biomarkers, Tumor/genetics , Esophageal Neoplasms/genetics , Intracellular Signaling Peptides and Proteins/genetics , Sirtuins/genetics , Apoptosis/genetics , Autophagy/genetics , Autophagy-Related Protein-1 Homolog/biosynthesis , Biomarkers, Tumor/biosynthesis , Cell Line, Tumor , Cell Proliferation/genetics , Esophageal Neoplasms/pathology , Gene Expression Regulation, Neoplastic , Glycolysis/genetics , Humans , Intracellular Signaling Peptides and Proteins/biosynthesis , Sirolimus/administration & dosage , Sirtuins/biosynthesis
13.
Tumour Biol ; 2016 Oct 14.
Article in English | MEDLINE | ID: mdl-27743378

ABSTRACT

The serine/threonine protein kinase CHK1 has been reported to bind to the recombinase RAD51 and facilitates its assembly in DNA damage sites via phosphorylation. However, the role of RAD51 in regulating the expression of CHK1 has never been explored. Here, we show that RAD51 is highly upregulated in esophageal squamous tumor tissues and its DMC1 domain significantly promotes cell growth of esophageal cancer (EC) cells through CHK1. To gain the mechanistic insights, firstly, in the presence of 3-methyladenine (3MA), an autophagy inhibitor, we found that the reduction of CHK1 and the inhibition of cell growth in RAD51-deficient EC109 cells were strikingly restored. Subsequently, the autophagy-related experiments revealed that RAD51 negatively participated in autophagy. Moreover, results from in vitro clonogenic survival assays showed that RAD51 depletion greatly enabled EC cells to resist the autophagy inhibitors 3MA and hydroxychloroquine (HCQ) treatments. Above all, our studies firstly highlight a direct role of RAD51 in autophagy process and characterize its functional domain in cell growth regulation. Moreover, our data firstly shed insights into the possible application of autophagy inhibitors in treating RAD51 overexpressed EC patients.

14.
Inorg Chem ; 55(11): 5710-8, 2016 Jun 06.
Article in English | MEDLINE | ID: mdl-27191197

ABSTRACT

A pair of chiral ruthenium(II) complexes, Λ- and Δ-[Ru(bpy)2(p-BEPIP)](ClO4)2 [Λ- and Δ-RM0627; bpy = 2,2-bipyridine; p-BEPIP = 2-(4-phenyacetylenephenyl)-1H-imidazo[4,5f][1,10]phenanthroline], were prepared using the Sonogashira coupling reaction under microwave irradiation. The study shows that Λ-RM0627 emitted strong phosphorescence in the range 500-700 nm with a maximum at 594 nm when excited at 365 nm (the Stokes shift is about 227 nm), which was mainly located in the cell nucleus with red phosphorescence. Further studies using real-time phosphorescence observation confirmed that Λ-RM0627 can be taken up quickly by MDA-MB-231 cells and enriched in the nucleus. The in vitro and in vivo toxicities of Λ-RM0627 were also evaluated, and it was found that Λ-RM0627 slightly inhibited the growth of MDA-MB-231 breast cancer cells and HaCaT normal human epidermal cells and had little influence on the development of Zebrafish embryos at low concentration. In conclusion, the levoisomer of chiral ruthenium complexes can act as a potential phosphorescent probe that targets nuclei of living cells with low toxicity.


Subject(s)
Breast Neoplasms/pathology , Cell Nucleus/ultrastructure , Coordination Complexes/chemistry , Phenanthrolines/chemistry , Ruthenium Compounds/chemistry , Animals , Cell Line, Tumor , Humans , Spectrum Analysis/methods , Stereoisomerism , Zebrafish/embryology
15.
J Biol Chem ; 289(10): 6921-6933, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24482231

ABSTRACT

Cluster of differentiation 166 (CD166 or Alcam) is a cell surface molecule that can be greatly induced in liver cancer cells after serum deprivation, suggesting its role in influencing cell survival. However, whether and how CD166 acts as an anti-apoptotic regulator needs to be further investigated. Here, we report that gene silencing of CD166 promoted apoptosis via down-regulation of Bcl-2 in liver cancer cells. PI3K/AKT signaling was found to up-regulate CD166 expression independently of transcription. We also revealed that CD166 promoted both AKT expression and activity, thus providing a novel positive regulatory feedback between PI3K/AKT signaling and CD166. Moreover, Yes-associated protein (YAP) was identified as a CD166 downstream effecter, which can partly rescue CD166 knockdown-induced apoptosis and reduced in vivo cancer cell growth. Mechanically, CD166 modulated YAP expression and activity through at least two different ways, transcriptional regulation of YAP through cAMP-response element-binding protein and post-transcriptional control of YAP stability through inhibition to AMOT130. We also showed that CD9 enhanced CD166-mediated regulation of YAP via a mechanism involving facilitating CD166-CD166 homophilic interaction. Tissue microarray analysis revealed that CD166 and YAP were up-regulated and closely correlated in liver cancer samples, demonstrating the importance of their relationship. Taken together, this work summarizes a novel link between CD166 and YAP, explores the interplay among related important signaling pathways, and may lead to more effective therapeutic strategies for liver cancer.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Antigens, CD/biosynthesis , Apoptosis , Cell Adhesion Molecules, Neuronal/biosynthesis , Fetal Proteins/biosynthesis , Liver Neoplasms/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphoproteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Antigens, CD/genetics , Cell Adhesion Molecules, Neuronal/genetics , Fetal Proteins/genetics , Hep G2 Cells , Humans , Liver Neoplasms/pathology , Signal Transduction , Transcription Factors , YAP-Signaling Proteins
16.
Dev Growth Differ ; 57(8): 581-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26449203

ABSTRACT

Cellular retinoic acid binding protein 2 (CRABP2) is essential for myoblast differentiation, however, little is known about its role in osteogenic differentiation. This study mainly aims to explore the biological functions and the underlying molecular mechanisms of CRABP2 in osteogenesis. Using quantitative polymerase chain reaction and western blot assays, we found that the expression of CRABP2 at both mRNA and protein levels were downregulated during osteogenesis. Furthermore, CRABP2 knockdown displayed significant changes in the cell phenotype and the actin filaments (F-actin) polymerization in C2C12 cells treated with BMP2. Moreover, the western blotting of osteogenic differentiation biomarkers, alkaline phosphatase (ALP) staining and Alizarin red staining showed that CRABP2 dramatically inhibited osteogenic differentiation. The following investigation of molecular mechanisms implicated that CARBP2 specifically interacted with LIMK1, a key factor in acin cytoskeletal rearrangements in osteogenesis, to interrupt its activity and stability in an ubiquitin-proteasome pathway to prevent C2C12 cells from osteogenic differentiation in response to BMP2. Above all, our data suggest a novel function of CRABP2 in regulating actin remodeling and osteogenic differentiation via LIMK1, thus presenting a possible molecular target for promoting the osteogenic differentiation in bone degenerative diseases.


Subject(s)
Lim Kinases/metabolism , Receptors, Retinoic Acid/metabolism , Actins/metabolism , Animals , Bone Morphogenetic Protein 2/pharmacology , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Line , Lim Kinases/genetics , Mice , Osteogenesis/genetics , Osteogenesis/physiology , Protein Binding , Receptors, Retinoic Acid/genetics
17.
Carcinogenesis ; 35(7): 1643-51, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24710624

ABSTRACT

Neurotrophin receptor-interacting melanoma antigen-encoding gene homolog (NRAGE) is generally recognized as a tumor suppressor as it induces cell apoptosis and suppresses cell metastasis. However, it has recently been reported that NRAGE is overexpressed in lung cancer, melanoma and colon cancer, implicating a complicated role of NRAGE as we have expected. In the study, we aim to elucidate the functional roles and molecular mechanisms of NRAGE in esophageal carcinoma. We found that both NRAGE mRNA and protein were significantly overexpressed in esophageal tumor tissues. Consistently, both in vivo and in vitro analyses demonstrated that knockdown of NRAGE apparently inhibited cell growth, and cell cycle analysis further demonstrated that NRAGE knockdown cells were mainly arrested in G2M cell phase, accompanied with an apparent reduction of S phase. In the process of exploring molecular mechanisms, we found that either knockdown in vitro or knockout in vivo of NRAGE reduced proliferating cell nuclear antigen (PCNA) protein, expression of which could completely rescue the inhibited proliferation in NRAGE defective cells. Furthermore, NRAGE physically interacted with PCNA in esophageal cancer cells through DNA polymerase III subunit, and knockdown of NRAGE facilitated PCNA K48-linked polyubiquitination, leading PCNA to the proteasome-dependent degradation and a ubiquitin-specific protease USP10 was identified to be a key regulator in the process of K48 polyubiquitination in NRAGE-deleted cells. In conclusion, our study highlights a unique role of NRAGE and implies that NRAGE is likely to be an attractive oncotarget in developing novel genetic anticancer therapeutic strategies for esophageal squamous cell carcinomas.


Subject(s)
Antigens, Neoplasm/metabolism , Cell Proliferation , Esophageal Neoplasms/pathology , Esophagus/metabolism , Neoplasm Proteins/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Proteasome Endopeptidase Complex/metabolism , Ubiquitins/metabolism , Animals , Antigens, Neoplasm/genetics , Blotting, Western , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Cohort Studies , Esophageal Neoplasms/genetics , Esophageal Neoplasms/metabolism , Female , Fluorescent Antibody Technique , Humans , Immunoenzyme Techniques , Immunoprecipitation , Lymphatic Metastasis , Male , Mice , Mice, Nude , Middle Aged , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/genetics , Neoplasm Staging , Proliferating Cell Nuclear Antigen/genetics , Proteasome Endopeptidase Complex/genetics , Proteolysis , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tissue Array Analysis , Tumor Cells, Cultured , Ubiquitin Thiolesterase/genetics , Ubiquitin Thiolesterase/metabolism , Xenograft Model Antitumor Assays
18.
J Biol Chem ; 288(47): 33667-33681, 2013 Nov 22.
Article in English | MEDLINE | ID: mdl-24089522

ABSTRACT

Tribbles homolog 2 (TRIB2) is critical for both solid and non-solid malignancies. Recently, TRIB2 was identified as a liver cancer-specific Wnt/ß-catenin signaling downstream target and is functionally important for liver cancer cell survival and transformation. TRIB2 functions as a protein that interacts with E3 ubiquitin ligases and thereby modulates protein stability of downstream effectors. However, the regulation underlying TRIB2 protein stability per se has not yet been reported. In this study, we found that TRIB2 was up-regulated and exhibited high stability in liver cancer cells compared with other cells. We performed a structure-function analysis of TRIB2 and identified a domain (amino acids 1-5) at the N terminus that interacted with the E3 ubiquitin ligase Smurf1 and was critical for protein stability. Deletion of this domain extended TRIB2 half-life time accompanied with a more significant malignant property compared with wild type TRIB2. Furthermore, Smurf1-mediated ubiquitination required phosphorylation of TRIB2 by p70 S6 kinase (p70S6K) via another domain (amino acids 69-85) that is also essential for correct TRIB2 subcellular localization. Mutation of Ser-83 diminished p70S6K-induced phosphorylation of TRIB2. Moreover, the high stability of TRIB2 may be due to the fact that both p70S6K and Smurf1 were down-regulated and negatively correlated with TRIB2 expression in both liver cancer tissues and established liver cancer cell lines. Taken together, impaired phosphorylation and ubiquitination by p70S6K and Smurf1 increase the protein stability of TRIB2 in liver cancer and thus may be helpful in the development of diagnosis and treatment strategies against this malignant disease.


Subject(s)
Gene Expression Regulation, Neoplastic , Intracellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/metabolism , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , Ubiquitin-Protein Ligases/biosynthesis , Ubiquitination , Calcium-Calmodulin-Dependent Protein Kinases , Down-Regulation/genetics , Hep G2 Cells , Humans , Intracellular Signaling Peptides and Proteins/genetics , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Phosphorylation/genetics , Protein Stability , Protein Structure, Tertiary , Protein Transport/genetics , Ribosomal Protein S6 Kinases, 70-kDa/genetics , Ubiquitin-Protein Ligases/genetics
19.
Biochim Biophys Acta ; 1832(10): 1528-37, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23688781

ABSTRACT

OBJECTIVES: The human genome encodes many long intergenic noncoding RNAs (lincRNAs). However, their biological functions, molecular mechanisms and prognostic values associated with bladder cancer remain to be elucidated. Here we investigated a lincRNA termed linc-UBC1 (Up-regulated in bladder cancer 1) and evaluated its prognostic value in bladder cancer patients. MATERIALS AND METHODS: Expression of linc-UBC1 was evaluated by quantitative reverse transcription PCR (qRT-PCR) in 102 bladder cancer tissue samples and normal adjacent tissues. The functions of linc-UBC1 on cell proliferation, migration, invasion, colony formation, tumorigenicity and metastatic potential were evaluated by knockdown strategy in vitro and in vivo. RNA immunoprecipitation (RIP) was performed to confirm that linc-UBC1 physically associates with EZH2 and SUZ12, core components of polycomb repressive complex 2 (PRC2). Chromatin immunoprecipitation (ChIP) was conducted to examine histone modification status. RESULTS: qRT-PCR confirmed that linc-UBC1 expression is up-regulated in 60 cases (58.8%) in bladder cancer tissues compared with normal adjacent tissues, and its overexpression correlates with lymph node metastasis and poor survival. Further functional analysis demonstrated that knockdown of linc-UBC1 attenuates bladder cancer cell proliferation, motility, invasion, colony formation ability, tumorigenicity and metastatic potential. Importantly, the inhibitory effect of linc-UBC1 on cell proliferation was also observed in primary bladder cancer cells obtained from patients. RIP and ChIP assay confirmed that linc-UBC1 physically associates with PRC2 complex and regulates histone modification status of target genes. CONCLUSIONS: Frequently overexpressed linc-UBC1 physically associates with PRC2 complex, and acts as a negative prognostic factor for lymph node metastasis and survival in bladder cancer.


Subject(s)
Lymphatic Metastasis , Polycomb Repressive Complex 2/metabolism , RNA, Long Noncoding , Urinary Bladder Neoplasms/metabolism , Aged , Animals , Female , Humans , Male , Mice , Middle Aged , Prognosis , Protein Binding , Survival Rate , Tumor Cells, Cultured , Urinary Bladder Neoplasms/pathology
20.
Biochem Biophys Res Commun ; 451(2): 334-8, 2014 Aug 22.
Article in English | MEDLINE | ID: mdl-25094049

ABSTRACT

Cluster of differentiation 166 (CD166) is critical for liver cancer cell survival. Our previously study demonstrated that CD166 exerts its anti-apoptotic role through interaction with YAP in liver cancer. However, the interaction between CD166 and other cell surface molecules remains unclear in liver cancer cells. In the current study, we found that both mRNA and protein of CD44 expression was significantly inhibited by knocking-down CD166. Moreover, CD166 affected-CD44 expression is dependent of transcription via blocking NF-κB pathway. On the contrary, CD44 promoted up-regulation of CD166 mRNA and protein. And it may be through E3 ubiquitin ligases COP1 and UBC3 to regulate CD166 protein degradation. Collectively, these results suggest that CD166 and CD44 play important roles in liver cancer development. Therefore, CD166 may develop as a potential therapeutic molecule target for the treatment of liver cancer.


Subject(s)
Antigens, CD/genetics , Antigens, CD/metabolism , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Cell Adhesion Molecules, Neuronal/genetics , Cell Adhesion Molecules, Neuronal/metabolism , Fetal Proteins/genetics , Fetal Proteins/metabolism , Hyaluronan Receptors/genetics , Hyaluronan Receptors/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , NF-kappa B/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Apoptosis , Carcinoma, Hepatocellular/pathology , Cell Adhesion Molecules, Neuronal/antagonists & inhibitors , Cell Line, Tumor , Cell Proliferation , Fetal Proteins/antagonists & inhibitors , Gene Knockdown Techniques , Humans , Liver Neoplasms/pathology , Phosphoproteins/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , Signal Transduction , Transcription Factors , Up-Regulation , YAP-Signaling Proteins
SELECTION OF CITATIONS
SEARCH DETAIL