Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 55
Filter
1.
J Nanobiotechnology ; 22(1): 479, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39134988

ABSTRACT

The prevention and treatment of gastrointestinal mucosal injury caused by a plateau hypoxic environment is a clinical conundrum due to the unclear mechanism of this syndrome; however, oxidative stress and microbiota dysbiosis may be involved. The Robinia pseudoacacia L. flower, homologous to a functional food, exhibits various pharmacological effects, such as antioxidant, antibacterial, and hemostatic activities. An increasing number of studies have revealed that plant exosome-like nanoparticles (PELNs) can improve the intestinal microbiota and exert antioxidant effects. In this study, the oral administration of Robinia pseudoacacia L. flower exosome-like nanoparticles (RFELNs) significantly ameliorated hypoxia-induced gastric and small intestinal mucosal injury in mice by downregulating hypoxia-inducible factor-1α (HIF-1α) and HIF-2α expression and inhibiting hypoxia-mediated ferroptosis. In addition, oral RFELNs partially improved hypoxia-induced microbial and metabolic disorders of the stomach and small intestine. Notably, RFELNs displayed specific targeting to the gastrointestinal tract. In vitro experiments using gastric and small intestinal epithelial cell lines showed that cell death caused by elevated HIF-1α and HIF-2α under 1% O2 mainly occurred via ferroptosis. RFELNs obviously inhibited HIF-1α and HIF-2α expression and downregulated the expression of NOX4 and ALOX5, which drive reactive oxygen species production and lipid peroxidation, respectively, suppressing ferroptosis under hypoxia. In conclusion, our findings underscore the potential of oral RFELNs as novel, naturally derived agents targeting the gastrointestinal tract, providing a promising therapeutic approach for hypoxia-induced gastric and small intestinal mucosal ferroptosis.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors , Exosomes , Ferroptosis , Flowers , Gastric Mucosa , Hypoxia-Inducible Factor 1, alpha Subunit , Intestinal Mucosa , Intestine, Small , Lipid Peroxidation , Nanoparticles , Animals , Ferroptosis/drug effects , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mice , Exosomes/metabolism , Exosomes/drug effects , Lipid Peroxidation/drug effects , Intestine, Small/drug effects , Intestine, Small/metabolism , Intestine, Small/pathology , Administration, Oral , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Male , Basic Helix-Loop-Helix Transcription Factors/metabolism , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Flowers/chemistry , Nanoparticles/chemistry , Hypoxia/drug therapy , Hypoxia/metabolism , Humans , Mice, Inbred C57BL
2.
Mol Pharm ; 20(8): 4007-4020, 2023 08 07.
Article in English | MEDLINE | ID: mdl-37427910

ABSTRACT

Distant metastasis of malignant tumors is considered to be the main culprit for the failure of current antitumor treatments. Conventional single treatments often exhibit limited efficacy in inhibiting tumor metastasis. Therefore, there is a growing interest in developing collaborative antitumor strategies based on photothermal therapy (PTT) and free-radical-generated photodynamic therapy (PDT), especially utilizing oxygen-independent nanoplatforms, to address this challenge. Such antitumor strategies can enhance the therapeutic outcomes by ensuring the cytotoxicity of free radicals even in the hypoxic tumor microenvironment, thereby improving the effective suppression of primary tumors. Additionally, these approaches can stimulate the production of tumor-associated antigens and amplify the immunogenic cell death (ICD) effects, potentially feasible for enhancing the therapeutic outcomes of immunotherapy. Herein, we fabricated a functional nanosystem that co-loads IR780 and 2,2'-azobis[2-(2-imidazolin-2-yl)propane]-dihydrochloride (AIPH) to realize PTT-triggered thermodynamic combination therapy via the oxygen-independent pathway for the elimination of primary tumors. Furthermore, the nanocomposites were surface-decorated with a predesigned complex peptide (PLGVRGC-anti-PD-L1 peptide, MMP-sensitive), which facilitated the immunotherapy targeting distant tumors. Through the specific recognition of matrix metalloproteinase (MMP), the sensitive segment on the obtained aNC@IR780A was cleaved. As a result, the freed anti-PD-L1 peptide effectively blocked immune checkpoints, leading to the infiltration and activation of T cells (CTLs). This nanosystem was proven to be effective at inhibiting both primary tumors and distant tumors, providing a promising combination strategy for tumor PTT/TDT/immunotherapy.


Subject(s)
Nanoparticles , Phototherapy , Cell Line, Tumor , Immunotherapy , Oxygen , Peptides , Polymers , Thermodynamics , Tumor Microenvironment , Humans
3.
Mol Cell ; 53(5): 752-65, 2014 Mar 06.
Article in English | MEDLINE | ID: mdl-24530303

ABSTRACT

Impaired phosphatase activity contributes to the persistent activation of STAT3 in tumors. Given that STAT family members with various or even opposite functions are often phosphorylated or dephosphorylated by the same enzymes, the mechanism for STAT3-specific dephosphorylation in cells remains largely unknown. Here, we report that GdX (UBL4A) promotes STAT3 dephosphorylation via mediating the interaction between TC45 (the nuclear isoform of TC-PTP) and STAT3 specifically. GdX stabilizes the TC45-STAT3 complex to bestow upon STAT3 an efficient dephosphorylation by TC45. Inasmuch, GdX suppresses tumorigenesis and tumor development by reducing the level of phospho-STAT3 (p-STAT3), whereas deletion of GdX results in a high level of p-STAT3 and accelerated colorectal tumorigenesis induced by AOM/DSS. Thus, GdX converts TC45, a nonspecific phosphatase, into a STAT3-specific phosphatase by bridging an association between TC45 and STAT3.


Subject(s)
Carcinogenesis , Gene Expression Regulation, Neoplastic , Protein Tyrosine Phosphatase, Non-Receptor Type 2/chemistry , STAT3 Transcription Factor/chemistry , Ubiquitins/chemistry , Animals , COS Cells , Cell Transformation, Neoplastic , Chlorocebus aethiops , Cytokines/metabolism , Fibroblasts/metabolism , Gene Deletion , Humans , MCF-7 Cells , Melanoma, Experimental , Mice , Mice, Inbred BALB C , Neoplasm Metastasis , Neoplasm Transplantation , Phosphorylation , Protein Binding , Ubiquitins/genetics
4.
Br J Cancer ; 124(8): 1437-1448, 2021 04.
Article in English | MEDLINE | ID: mdl-33531691

ABSTRACT

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) has been shown to upregulate gene transcription during tumorigenesis. However, how STAT3 initiates transcription remains to be exploited. This study is to reveal the role of CREPT (cell cycle-related and elevated-expression protein in tumours, or RPRD1B) in promoting STAT3 transcriptional activity. METHODS: BALB/c nude mice, CREPT overexpression or deletion cells were employed for the assay of tumour formation, chromatin immunoprecipitation, assay for transposase-accessible chromatin using sequencing. RESULTS: We demonstrate that CREPT, a recently identified oncoprotein, enhances STAT3 transcriptional activity to promote tumorigenesis. CREPT expression is positively correlated with activation of STAT3 signalling in tumours. Deletion of CREPT led to a decrease, but overexpression of CREPT resulted in an increase, in STAT3-initiated tumour cell proliferation, colony formation and tumour growth. Mechanistically, CREPT interacts with phosphorylated STAT3 (p-STAT3) and facilitates p-STAT3 to recruit p300 to occupy at the promoters of STAT3-targeted genes. Therefore, CREPT and STAT3 coordinately facilitate p300-mediated acetylation of histone 3 (H3K18ac and H3K27ac), further augmenting RNA polymerase II recruitment. Accordingly, depletion of p300 abolished CREPT-enhanced STAT3 transcriptional activity. CONCLUSIONS: We propose that CREPT is a co-activator of STAT3 for recruiting p300. Our study provides an alternative strategy for the therapy of cancers related to STAT3.


Subject(s)
Cell Cycle Proteins/metabolism , Cell Transformation, Neoplastic/pathology , E1A-Associated p300 Protein/metabolism , Neoplasm Proteins/metabolism , STAT3 Transcription Factor/genetics , STAT3 Transcription Factor/metabolism , Animals , Cell Cycle Proteins/genetics , Cell Line, Tumor , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Female , HEK293 Cells , Humans , MCF-7 Cells , Mice , Mice, Inbred BALB C , Mice, Nude , NIH 3T3 Cells , Neoplasm Proteins/genetics , Neoplasm Transplantation , Phosphorylation , Transcription, Genetic
5.
J Cell Biochem ; 121(2): 1541-1551, 2020 02.
Article in English | MEDLINE | ID: mdl-31535402

ABSTRACT

Mesenchymal stem cells (MSCs) have been proved to exert anti-inflammatory effects and regulate immune reactions. Traditional Chinese medicine (TCM), qi-fang-bi-min-tang, is effective for some patients with allergic diseases. However, it remains unclear whether MSCs combined with TCM could benefit the treatment of allergic rhinitis (AR). In this study, we reported an additional effect of TCM (qi-fang-bi-min-tang) on the therapy of AR under MSCs treatment. Intriguingly, we observed that TCM-treated MSCs significantly inhibited the symptoms of AR and reduced the pathological changes of nasal mucosa in ovalbumin (OVA)-induced rats. The expression levels of interferon Î³ (IFN-γ), interleukin-17 (IL-17), and IL-4 were significantly decreased in the plasma of AR rats after injection of TCM-treated MSCs. TCM-treated MSCs reduced the levels of histamine secreted by mast cells and immunoglobulin E (IgE) secreted by plasma cells. In addition, we found that MSCs combined with TCM had a better therapeutic effect than TCM alone on AR in an OVA-induced mouse model. After OVA induction, MSCs combined with TCM significantly reduced the ratio of T helper type 1 (Th1), Th2, and Th17, but increased the proportion of Treg in the spleen of mice. Consistently, the expression levels of IFN-γ, IL-4, and IL-17 were significantly decreased, but transforming growth factor-ß1 was significantly increased in the plasma of AR mice after treated with TCM and MSCs. Our results from both rats and mice indicated that the effects of TCM combined with MSCs on the AR might be through regulating the secretion of Th1, Th2, and Th17 cytokines. This study suggested that TCM (qi-fang-bi-min-tang)-treated MSCs could be used in the clinical therapy of AR.


Subject(s)
Drugs, Chinese Herbal/pharmacology , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/immunology , Rhinitis, Allergic/therapy , Allografts , Animals , Cytokines/immunology , Male , Mesenchymal Stem Cells/pathology , Mice , Mice, Inbred BALB C , Rats , Rats, Sprague-Dawley , Rhinitis, Allergic/immunology , Rhinitis, Allergic/pathology , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/pathology
6.
FASEB J ; 33(7): 8375-8385, 2019 07.
Article in English | MEDLINE | ID: mdl-31002527

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune disease associated with synovial hyperplasia and bone and cartilage destruction. T cells, notably T helper (Th)-1 and Th17 cells, play a critical role in the pathologic process of RA. However, it remains unclear how Th1 and Th17 cells are regulated during RA. In this study, we report that the small ubiquitin-like protein X-linked gene in the G6PD cluster at Xq28 (GdX) regulates the balance of Th17 and regulatory T (Treg) cells during collagen-induced arthritis (CIA). We discovered that the splenocytes of GdX-knockout (KO) mice were insensitive to T-cell stimulants. Correspondingly, GdX-KO mice showed alleviative Th1-mediated delayed-type hypersensitivity and were resistant to CIA compared with wild-type mice. GdX-KO mice showed fewer swollen paws, lower serum proinflammatory cytokine and anti-collagen IgG levels, and decreased synovial hyperplasia. Mechanistically, we observed that deletion of GdX decreased the transcription of proinflammatory cytokines and impaired the Th1 and Th17 differentiation but increased the Treg cell proliferation. Consistently, deletion of GdX decreased the transcription level of T-cell-specific T-box transcription factor and RAR-related orphan receptor-γ transcription factor but increased that of forkhead box P3 after being challenged with type-II collagen. These findings suggested that GdX functions as an important regulator of Th1 or Th17 and Treg cell balance during the inflammatory responses. Therefore, GdX may be a potential target for the therapy of RA.-Fu, Y., Liu, S., Wang, Y., Ren, F., Fan, X., Liang, J., Liu, C., Li, J., Ju, Y., Chang, Z. GdX/UBL4A-knockout mice resist collagen-induced arthritis by balancing the population of Th1/Th17 and regulatory T cells.


Subject(s)
Arthritis, Experimental/enzymology , T-Lymphocytes, Regulatory/enzymology , Th1 Cells/enzymology , Th17 Cells/enzymology , Ubiquitins/deficiency , Animals , Arthritis, Experimental/genetics , Arthritis, Experimental/pathology , Cytokines/genetics , Cytokines/metabolism , Male , Mice , Mice, Knockout , Th1 Cells/pathology , Th17 Cells/pathology , Transcription, Genetic , Ubiquitins/metabolism
7.
J Biol Chem ; 293(20): 7618-7628, 2018 05 18.
Article in English | MEDLINE | ID: mdl-29618509

ABSTRACT

We previously demonstrated that p15RS, a newly discovered tumor suppressor, inhibits Wnt/ß-catenin signaling by interrupting the formation of ß-catenin·TCF4 complex. However, it remains unclear how p15RS helps exert such an inhibitory effect on Wnt signaling based on its molecular structure. In this study, we reported that dimerization of p15RS is required for its inhibition on the transcription regulation of Wnt-targeted genes. We found that p15RS forms a dimer through a highly conserved leucine zipper-like motif in the coiled-coil terminus domain. In particular, residues Leu-248 and Leu-255 were identified as being responsible for p15RS dimerization, as mutation of these two leucines into prolines disrupted the homodimer formation of p15RS and weakened its suppression of Wnt signaling. Functional studies further confirmed that mutations of p15RS at these residues results in diminishment of its inhibition on cell proliferation and tumor formation. We therefore concluded that dimerization of p15RS governed by the leucine zipper-like motif is critical for its inhibition of Wnt/ß-catenin signaling and tumorigenesis.


Subject(s)
Gene Expression Regulation, Neoplastic , Leucine Zippers , Melanoma/prevention & control , Repressor Proteins/chemistry , Animals , Apoptosis , Cell Proliferation , Female , Melanoma/metabolism , Melanoma/pathology , Mice , Mice, Inbred BALB C , Mice, Nude , Protein Multimerization , Repressor Proteins/genetics , Repressor Proteins/metabolism , Transcription Factor 4/antagonists & inhibitors , Transcription Factor 4/genetics , Transcription Factor 4/metabolism , Tumor Cells, Cultured , Wnt Signaling Pathway , beta Catenin/antagonists & inhibitors , beta Catenin/metabolism
8.
Mol Carcinog ; 57(10): 1408-1420, 2018 10.
Article in English | MEDLINE | ID: mdl-29938829

ABSTRACT

CREPT (Cell-cycle-related and expression-elevated protein in tumor)/RPRD1B, a novel protein that enhances the transcription of Cyclin D1 to promote cell proliferation during tumorigenesis, was demonstrated highly expressed in most of tumors. However, it remains unclear how CREPT is regulated in colorectal cancers. In this study, we report that miR-383 negatively regulates CREPT expression. We observed that CREPT was up-regulated but the expression of miR-383 was down regulated in both colon cancer cell lines and colon tumor tissues. Intriguingly, we found that enforced expression of miR-383 inhibited the expression of CREPT at both the mRNA and protein level. Using a luciferase reporter, we showed that miR-383 targeted the 3'-UTR of CREPT mRNA directly. Consistently we observed that over expression of miR-383 shortened the half-life of CREPT mRNA in varieties of colorectal cancer cells. Furthermore, restoration of miR-383 inhibited cell growth and colony formation of colon cancer cells accompanied by inhibition of expression of CREPT and related downstream genes. Finally, we demonstrated that stable over expression of miR-383 in colon cancer cells decreased the growth of the tumors. Our results revealed that the abundant expression of CREPT in colorectal cancers is attributed to the decreased level of miR-383. This study shed a new light on the potential therapeutic therapy strategy for colorectal cancers using introduced miRNA.


Subject(s)
Cell Cycle Proteins/genetics , Colorectal Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , MicroRNAs/genetics , Neoplasm Proteins/genetics , 3' Untranslated Regions/genetics , Aged , Cell Cycle Proteins/metabolism , Cell Line , Cell Line, Tumor , Cell Proliferation/genetics , Colorectal Neoplasms/metabolism , Female , HCT116 Cells , HEK293 Cells , HT29 Cells , Humans , Male , Middle Aged , Neoplasm Proteins/metabolism , RNA Stability/genetics
9.
Cell Biochem Funct ; 36(3): 129-136, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29464742

ABSTRACT

GdX, also named ubiquitin-like protein 4A, is a ubiquitin-domain protein characterized by a ubiquitin-like domain that regulates the movement of misfolded proteins from the endoplasmic reticulum membrane to proteasome. However, its function in skeletal biology remains unclear. Here, we report that GdX plays a crucial role in skeletal development as mice lacking GdX exhibit skeletal dysplasias, mild kyphosis, and scoliosis. During embryonic stage, GdX knockout mice display decreased bone mineral density and trabecular bone accompanied by delayed osteogenic formation. GdX knockout mice also have blended spine and small body size. At the molecular level, GdX knockout mice showed perturbed expression of osteogenesis-related genes and cartilage developmental genes, indicative of altered differentiation of mesenchymal cell lineage. Collectively, our results uncovered GdX as a novel regulator in bone development and a potential candidate gene for skeletal dysplasias.


Subject(s)
Chondrogenesis , Kyphosis/metabolism , Osteoblasts/metabolism , Osteogenesis , Scoliosis/metabolism , Ubiquitins/metabolism , Animals , Cells, Cultured , Mice, Knockout , Ubiquitins/deficiency
10.
Cell Biochem Funct ; 35(7): 420-425, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28940415

ABSTRACT

Mesenchymal stromal cells (MSCs) have been extensively investigated as a potential antiinflammatory treatment in many inflammatory-related diseases; however, it remains unclear whether MSCs could be used to treat acute allergic rhinitis. A rat model of allergic rhinitis was treated with MSCs. The effect of MSCs on the inflammation of allergic rhinitis was evaluated by sneezing, nose rubbing, the pathology of the nasal mucosa, and the expression of interleukin 4, tumour necrosis factor alpha, and immunoglobulin E in the serum of rats. Also, the population of MSCs isolated from umbilical cords of humans was evaluated to determine if they could inhibit the symptoms and inflammation of acute allergic rhinitis in a rat model. We observed that this population of cells inhibited sneezing, nose rubbing, and changes in the pathology of the nasal mucosa. Intriguingly, we observed that MSCs reduced the expression of interleukin 4, tumour necrosis factor alpha, and immunoglobulin E in the serum. Furthermore, MSCs reduced the expression of histamine and the recruitment of macrophages in the nasal mucosa of allergic rhinitis rats. We reasoned that the effect of MSCs on allergic rhinitis might be through its regulation of the secretion of related cytokines from macrophages during the process of acute allergic rhinitis. This work suggested that MSCs from the umbilical cords of humans could be used as a positive clinical therapy for the human disease.


Subject(s)
Mesenchymal Stem Cell Transplantation , Rhinitis, Allergic/therapy , Acute Disease , Animals , Cells, Cultured , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Histamine/blood , Humans , Immunoglobulin E/blood , Interleukin-4/blood , Macrophages/cytology , Macrophages/immunology , Male , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Nasal Mucosa/cytology , Nasal Mucosa/metabolism , Nasal Mucosa/pathology , Rats , Rats, Sprague-Dawley , Rhinitis, Allergic/metabolism , Rhinitis, Allergic/pathology , Transplantation, Heterologous , Tumor Necrosis Factor-alpha/blood , Umbilical Cord/cytology
11.
J Biol Chem ; 290(2): 861-71, 2015 Jan 09.
Article in English | MEDLINE | ID: mdl-25378394

ABSTRACT

TNF receptor 2 (TNFR2) exerts diverse roles in the pathogenesis of inflammatory and autoimmune diseases. Here, we report that TNFR2 but not TNFR1 forms a heteromer with interleukin-17 receptor D (IL-17RD), also named Sef, to activate NF-κB signaling. TNFR2 associates with IL-17RD, leading to mutual receptor aggregation and TRAF2 recruitment, which further activate the downstream cascade of NF-κB signaling. Depletion of IL-17RD impaired TNFR2-mediated activation of NF-κB signaling. Importantly, IL-17RD was markedly increased in renal tubular epithelial cells in nephritis rats, and a strong interaction of TNFR2 and IL-17RD was observed in the renal epithelia. The IL-17RD·TNFR2 complex in activation of NF-κB may explain the role of TNFR2 in inflammatory diseases including nephritis.


Subject(s)
Inflammation/metabolism , NF-kappa B/metabolism , Nephritis/metabolism , Receptors, Interleukin-17/metabolism , Receptors, Tumor Necrosis Factor, Type II/metabolism , Animals , Epithelial Cells/metabolism , Epithelial Cells/pathology , Humans , Inflammation/etiology , Inflammation/pathology , Kidney Tubules, Distal/metabolism , Kidney Tubules, Distal/pathology , NF-kappa B/genetics , Nephritis/etiology , Nephritis/pathology , Protein Multimerization , Rats , Receptors, Interleukin-17/chemistry , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type I/metabolism , Receptors, Tumor Necrosis Factor, Type II/chemistry , Signal Transduction/genetics , Transcriptional Activation/genetics
12.
J Biol Chem ; 290(15): 9701-13, 2015 Apr 10.
Article in English | MEDLINE | ID: mdl-25697359

ABSTRACT

We previously reported that p15RS (p15INK4b-related sequence), a regulation of nuclear pre-mRNA domain containing protein, inhibited Wnt signaling by interrupting the formation of the ß-catenin·TCF4 complex. However, how p15RS functions as an intrinsic repressor to repress transcription remains unclear. In this study, we show that p15RS, through a specific interaction with HDAC2 (histone deacetylase 2), a deacetylase that regulates gene transcription, maintains histone H3 in a deacetylated state in the promoter region of Wnt-targeted genes where ß-catenin·TCF4 is bound. We observed that histone deacetylase inhibitors impair the ability of p15RS in inhibiting Wnt/ß-catenin signaling. Depletion of HDAC2 markedly disabled p15RS inhibition of Wnt/ß-catenin-mediated transcription. Interestingly, overexpression of p15RS decreases the level of acetylated histone H3 in the c-MYC promoter. Finally, we demonstrate that p15RS significantly enhances the association of HDAC2 and TCF4 and enhances the occupancy of HDAC2 to DNA, resulting in the deacetylation of histone H3 and the failure of ß-catenin interaction. We propose that p15RS acts as an intrinsic transcriptional repressor for Wnt/ß-catenin-mediated gene transcription at least partially through recruiting HDAC2 to occupy the promoter and maintaining deacetylated histone H3.


Subject(s)
Cell Cycle Proteins/metabolism , Histone Deacetylase 2/metabolism , Repressor Proteins/metabolism , Wnt Signaling Pathway , beta Catenin/metabolism , Acetylation , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Blotting, Western , Cell Cycle Proteins/genetics , Cell Proliferation/genetics , Cyclin D1/genetics , Cyclin D1/metabolism , Gene Expression , HEK293 Cells , Histone Deacetylase 2/genetics , Histones/metabolism , Humans , MCF-7 Cells , Microscopy, Confocal , Promoter Regions, Genetic/genetics , Protein Binding , Proto-Oncogene Proteins c-myc/genetics , RNA Interference , Repressor Proteins/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factor 4 , Transcription Factors/genetics , beta Catenin/genetics
13.
J Biol Chem ; 289(33): 22589-22599, 2014 Aug 15.
Article in English | MEDLINE | ID: mdl-24982424

ABSTRACT

CREPT (cell cycle-related and expression elevated protein in tumor)/RPRD1B (regulation of nuclear pre-mRNA domain-containing protein 1B), highly expressed during tumorigenesis, was shown to enhance transcription of CCND1 and to promote cell proliferation by interacting with RNA polymerase II. However, which signaling pathway is involved in CREPT-mediated activation of gene transcription remains unclear. In this study, we reveal that CREPT participates in transcription of the Wnt/ß-catenin signaling activated genes through the ß-catenin and the TCF4 complex. Our results demonstrate that CREPT interacts with both ß-catenin and TCF4, and enhances the association of ß-catenin with TCF4, in response to Wnt stimulation. Furthermore, CREPT was shown to occupy at TCF4 binding sites (TBS) of the promoters of Wnt-targeted genes under Wnt stimulation. Interestingly, depletion of CREPT resulted in decreased occupancy of ß-catenin on TBS, and over-expression of CREPT enhances the activity of the ß-catenin·TCF4 complex to initiate transcription of Wnt target genes, which results in up-regulated cell proliferation and invasion. Our study suggests that CREPT acts as an activator to promote transcriptional activity of the ß-catenin·TCF4 complex in response to Wnt signaling.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Cell Cycle Proteins/metabolism , Neoplasm Proteins/metabolism , Transcription Factors/metabolism , Wnt Signaling Pathway/physiology , beta Catenin/metabolism , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Cell Cycle Proteins/genetics , Cell Proliferation/physiology , HEK293 Cells , HeLa Cells , Humans , Mice , Multiprotein Complexes/genetics , Multiprotein Complexes/metabolism , NIH 3T3 Cells , Neoplasm Proteins/genetics , Transcription Factor 4 , Transcription Factors/genetics , Transcription, Genetic/physiology , Up-Regulation/physiology , beta Catenin/genetics
14.
J Biol Chem ; 289(16): 11230-11241, 2014 Apr 18.
Article in English | MEDLINE | ID: mdl-24616100

ABSTRACT

Wnt signaling plays a pivotal role in cell proliferation, tissue homeostasis, and tumorigenesis. Dishevelled (Dvl) is a central node of Wnt signaling. Insulin receptor substrates (IRSs), as a critical component of insulin signaling, are involved in cell proliferation, metabolism, and cancer development. In this study, we report that IRS1/2 promotes Wnt/ß-catenin signaling by stabilizing Dvl2. We found that IRS1/2 interacts with Dvl2. Overexpression of IRS1/2 increased the protein level of Dvl2 and promoted canonical Wnt signaling, as evidenced by the increased T cell-specific factor 4 transcriptional activity and the up-regulation of expression of CYCLIN D1 and c-MYC, two Wnt target genes critical for cell growth, whereas depletion of IRS1/2 reduced the level of Dvl2 and attenuated Wnt/ß-catenin signaling. Biochemical analyses revealed that IRS1/2 decreased Lys-63-linked ubiquitination of Dvl2 and stabilized Dvl2 protein via suppressing its autophagy-mediated degradation. We further revealed that IRS1/2 blocks autophagy-induced formation of the Dvl2-p62/SQSTM1 complex, resulting in disabled association of Dvl2 to autophagosomes. We demonstrated that IRS1/2 promoted the induction of epithelial-mesenchymal transition (EMT) and cell proliferation in response to Wnt stimulation, whereas depletion of Dvl2 impaired the IRS1/2-mediated EMT and cell growth. Our findings revealed that IRS1/2 promotes EMT and cell proliferation through stabilizing Dvl2.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Autophagy/physiology , Epithelial-Mesenchymal Transition/physiology , Insulin Receptor Substrate Proteins/metabolism , Phosphoproteins/metabolism , Wnt Signaling Pathway/physiology , Adaptor Proteins, Signal Transducing/genetics , Cell Proliferation , Cyclin D1/genetics , Cyclin D1/metabolism , Dishevelled Proteins , HEK293 Cells , Humans , Insulin Receptor Substrate Proteins/genetics , Multiprotein Complexes/genetics , Multiprotein Complexes/metabolism , Phosphoproteins/genetics , Protein Stability , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Sequestosome-1 Protein , Transcription Factor 7-Like 2 Protein/genetics , Transcription Factor 7-Like 2 Protein/metabolism , Ubiquitination/physiology , Wnt Proteins/genetics , Wnt Proteins/metabolism , beta Catenin/genetics , beta Catenin/metabolism
15.
Biochim Biophys Acta ; 1843(7): 1237-47, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24657641

ABSTRACT

Fibroblast growth factors (FGFs) and their receptors (FGFRs) play significant roles in vertebrate organogenesis and morphogenesis. FGFR3 is a negative regulator of chondrogenesis and multiple mutations with constitutive activity of FGFR3 result in achondroplasia, one of the most common dwarfisms in humans, but the molecular mechanism remains elusive. In this study, we found that chondrocyte-specific deletion of BMP type I receptor a (Bmpr1a) rescued the bone overgrowth phenotype observed in Fgfr3 deficient mice by reducing chondrocyte differentiation. Consistently, using in vitro chondrogenic differentiation assay system, we demonstrated that FGFR3 inhibited BMPR1a-mediated chondrogenic differentiation. Furthermore, we showed that FGFR3 hyper-activation resulted in impaired BMP signaling in chondrocytes of mouse growth plates. We also found that FGFR3 inhibited BMP-2- or constitutively activated BMPR1-induced phosphorylation of Smads through a mechanism independent of its tyrosine kinase activity. We found that FGFR3 facilitates BMPR1a to degradation through Smurf1-mediated ubiquitination pathway. We demonstrated that down-regulation of BMP signaling by BMPR1 inhibitor dorsomorphin led to the retardation of chondrogenic differentiation, which mimics the effect of FGF-2 on chondrocytes and BMP-2 treatment partially rescued the retarded growth of cultured bone rudiments from thanatophoric dysplasia type II mice. Our findings reveal that FGFR3 promotes the degradation of BMPR1a, which plays an important role in the pathogenesis of FGFR3-related skeletal dysplasia.


Subject(s)
Achondroplasia/genetics , Bone Morphogenetic Protein Receptors, Type I/genetics , Chondrocytes/metabolism , Growth Plate/metabolism , Receptor, Fibroblast Growth Factor, Type 3/genetics , Achondroplasia/metabolism , Achondroplasia/pathology , Animals , Bone Morphogenetic Protein 2/metabolism , Bone Morphogenetic Protein 2/pharmacology , Bone Morphogenetic Protein Receptors, Type I/metabolism , Cell Differentiation , Chondrocytes/cytology , Chondrocytes/drug effects , Embryo, Mammalian , Fibroblast Growth Factor 2/metabolism , Fibroblast Growth Factor 2/pharmacology , Gene Expression Regulation, Developmental , Growth Plate/cytology , Growth Plate/growth & development , Humans , Mice , Mice, Knockout , Morphogenesis/genetics , Phosphorylation/drug effects , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Receptor, Fibroblast Growth Factor, Type 3/deficiency , Signal Transduction , Smad Proteins/genetics , Smad Proteins/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination/drug effects
16.
Carcinogenesis ; 35(5): 983-91, 2014 May.
Article in English | MEDLINE | ID: mdl-24302614

ABSTRACT

The carboxyl terminus of Hsc70-interacting protein (CHIP, also named Stub1), a U-box containing E3 ubiquitin ligase, is involved in degradation of certain oncogenic proteins. Recent studies indicated that CHIP suppresses tumor progression in human cancers by targeting Src-3, hypoxia inducible factor 1α, NF-κB, ErbB2 and c-Myc. Here, we report that CHIP was downregulated, predominantly, in the late stages of human colorectal cancer (CRC), and that the CHIP promoter was hypermethylated in CRC specimens. Overexpression of CHIP in HCT-116 cells resulted in impaired tumor growth in nude mice and decreased abilities of tumor cell migration and invasion. Conversely, depletion of CHIP in HCT-116 cells promoted tumor growth and increased tumor cell migration and invasion. CHIP was further found to negatively regulate NF-κB signaling in HCT-116 cells by promoting ubiquitination and degradation of p65, a subunit of the NF-κB complex. The suppressive effect of CHIP led to decreased expression of NF-κB-targeted oncogenes including Cyclin D1, c-Myc, MMP-2, VEGF and IL-8. We proposed that CHIP inhibits the malignancy of CRC cells, possibly through targeting NF-κB signaling. This study provides functional evidence for CHIP as a potential tumor suppressor in CRC, and CHIP expression may be a marker for stages of CRC.


Subject(s)
Colorectal Neoplasms/metabolism , NF-kappa B/metabolism , Signal Transduction , Tumor Suppressor Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Aged , Aged, 80 and over , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , DNA Methylation , Disease Models, Animal , Female , Gene Expression Regulation, Neoplastic , HCT116 Cells , Heterografts , Humans , Male , Mice , Middle Aged , Neoplasm Staging , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Promoter Regions, Genetic , Transcription Factor RelA/metabolism , Tumor Burden , Tumor Suppressor Proteins/genetics , Ubiquitin-Protein Ligases/genetics
17.
Biochem Biophys Res Commun ; 446(1): 387-92, 2014 Mar 28.
Article in English | MEDLINE | ID: mdl-24613385

ABSTRACT

Transforming growth factor-ß (TGF-ß) signaling plays an important role in regulation of a wide variety of cellular processes. Canonical TGF-ß signaling is mediated by Smads which were further regulated by several factors. We previously reported that E3 ubiquitin ligase CHIP (carboxyl terminus of Hsc70-interacting protein, also named Stub1) controlled the sensitivity of TGF-ß signaling by modulating the basal level of Smad3 through ubiquitin-mediated degradation. Here, we present evidence that Hsp70 and Hsp90 regulate the complex formation of Smad3/CHIP. Furthermore, we observed that over-expressed Hsp70 or inhibition of Hsp90 by geldanamycin (GA) leads to facilitated CHIP-induced ubiquitination and degradation of Smad3, which finally enhances TGF-ß signaling. In contrast, over-expressed Hsp90 antagonizes CHIP mediated Smad3 ubiquitination and degradation and desensitizes cells in response to TGF-ß signaling. Taken together, our data reveal an opposite role of Hsp70 and Hsp90 in regulating TGF-ß signaling by implicating CHIP-mediated Smad3 ubiquitination and degradation. This study provides a new insight into understanding the regulation of the TGF-ß signaling by chaperones.


Subject(s)
HSP70 Heat-Shock Proteins/metabolism , HSP90 Heat-Shock Proteins/metabolism , Transforming Growth Factor beta/metabolism , Ubiquitin-Protein Ligases/metabolism , Animals , COS Cells , Cell Line , Chlorocebus aethiops , HEK293 Cells , HSP70 Heat-Shock Proteins/chemistry , HSP90 Heat-Shock Proteins/chemistry , Humans , Mink , Multiprotein Complexes/chemistry , Multiprotein Complexes/metabolism , Proteolysis , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Signal Transduction , Smad3 Protein/chemistry , Smad3 Protein/metabolism , Ubiquitin-Protein Ligases/chemistry , Ubiquitination
18.
AMB Express ; 14(1): 63, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824272

ABSTRACT

Adequate bowel cleansing is crucial for endoscopic diagnosis and treatment, and the recovery of gut microbiota after intestinal cleansing is also important. A hypertonic syrup predominantly comprising L-arabinose and D-xylose (20% xylo-oligosaccharides) can be extracted from the hemicellulose of corn husks and cobs. L-Arabinose and xylo-oligosaccharides have been reported to relieve constipation and improve the gut microbial environment. This study evaluated the bowel cleansing effect of the aforementioned syrup and its influence on the organism and intestinal microbiota after cleansing in comparison with polyethylene glycol-4000 (PEG-4000) in mice. Bowel cleansing was performed using syrup or PEG-4000 in C57BL/6J mice, and the effect of intestinal preparation and its influence on serum electrolytes and gut microbiota after bowel cleansing were evaluated. The volume of intestinal residual feces in the syrup group was significantly lower than that in the PEG-4000 group. Additionally, syrup disturbed serum electrolytes more mildly than PEG-4000. Alpha diversity in the gut microbiota was significantly higher in the syrup group than in the PEG-4000 group on the first day after bowel cleansing. However, no difference in beta diversity was observed between the two groups. Syrup increased the abundance of Bifidobacteria and Christensenella and decreased the abundance of Akkermansia in comparison with PEG-4000 on the first day after bowel cleansing. Thus, this syrup has potential clinical use as a bowel cleansing agent given the above effects, its benefits and safety, and better taste and acceptability.

19.
Theranostics ; 14(2): 662-680, 2024.
Article in English | MEDLINE | ID: mdl-38169511

ABSTRACT

Rationale: Cancer local recurrence increases the mortality of patients, and might be caused by field cancerization, a pre-malignant alteration of normal epithelial cells. It has been suggested that cancer-derived small extracellular vesicles (CDEs) may contribute to field cancerization, but the underlying mechanisms remain poorly understood. In this study, we aim to identify the key regulatory factors within recipient cells under the instigation of CDEs. Methods: In vitro experiments were performed to demonstrate that CDEs promote the expression of CREPT in normal epithelial cells. TMT-based quantitative mass spectrometry was employed to investigate the proteomic differences between normal cells and tumor cells. Loss-of-function approaches by CRISPR-Cas9 system were used to assess the role of CREPT in CDEs-induced field cancerization. RNA-seq was performed to explore the genes regulated by CREPT during field cancerization. Results: CDEs promote field cancerization by inducing the expression of CREPT in non-malignant epithelial cells through activating the ERK signaling pathway. Intriguingly, CDEs failed to induce field cancerization when CREPT was deleted, highlighting the importance of CREPT. Transcriptomic analyses revealed that CDEs elicited inflammatory responses, primarily through activation of the TNF signaling pathway. CREPT, in turn, regulates the transduction of downstream signals of TNF by modulating the expression of TNFR2 and PI3K, thereby promoting inflammation-to-cancer transition. Conclusion: CREPT not only serves as a biomarker for field cancerization, but also emerges as a target for preventing the cancer local recurrence.


Subject(s)
Extracellular Vesicles , Neoplasms , Humans , Cell Line, Tumor , Proteomics , Cell Cycle Proteins/metabolism , Cell Proliferation/genetics , Neoplasm Proteins/genetics , Extracellular Vesicles/metabolism , Neoplasms/genetics
20.
Cell Signal ; 106: 110592, 2023 06.
Article in English | MEDLINE | ID: mdl-36641081

ABSTRACT

Natural compounds that interfere with tumor cell growth have potential to be used as therapeutic agents to treat cancers. Lachnochromonin (p71) is a small molecule isolated from Lachnum virgineum. Here, we reported the effect of p71 on human tumor cells, especially on breast cancer MCF-7 cells. We found that p71 significantly suppresses cell growth and induces apoptosis. The luciferase results demonstrated that p71 specifically attenuates the activation of JAK/STAT3 signaling. Biochemical analysis revealed that p71 blocks the phosphorylation of STAT3 tyrosine 705 and serine 727, resulting in down-regulation of c-Myc and Cyclin D1 expression level. Importantly, p71 inhibited cell growth, colony-formation, and migration through affecting STAT3 activity. These results implied that p71 may be used as a therapeutic agent against breast cancer.


Subject(s)
Apoptosis , Breast Neoplasms , Humans , Female , Cell Line, Tumor , Signal Transduction , Cell Proliferation , Phosphorylation , Breast Neoplasms/pathology , STAT3 Transcription Factor/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL