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1.
Se Pu ; 42(5): 465-473, 2024 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-38736390

RESUMO

A method based on gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) coupled with one-step QuEChERS technique was developed for the simultaneous determination of 15 N-nitrosamines in air-dried yak meat. The hydration volume, extraction solvent, extracting salt, and cleaning material were optimized according to the characteristics of the N-nitrosamines and sample matrix. The optimized conditions were as follows: 10 mL of purified water for sample hydration, acetonitrile as the extraction solvent for the sample after hydration, 4.0 g of anhydrous MgSO4 and 1.0 g of NaCl as extracting salts, 500 mg of MgSO4+25 mg of C18+50 mg of PSA as cleaning materials. Favorable recoveries of the 15 N-nitrosamines were obtained when the extraction solution was incompletely dried. Thus, the final extract was dried to below 0.5 mL under a mild nitrogen stream and then redissolved to 0.5 mL with acetonitrile. After filtration, 200 µL of the sample was transferred to an autosampler vial for GC-MS/MS analysis. The 15 N-nitrosamines were determined using GC-MS/MS on a DB-HeavyWAX column (30 m×0.25 mm×0.25 µm) with an electron impact ion source in multiple-reaction monitoring (MRM) mode, and quantified using an external standard method. Under the optimized experimental conditions, the results showed that the calibration curves exhibited good linearities for the 15 N-nitrosamines, with correlation coefficients (r2) greater than 0.9990. The limits of detection (LODs) and the limits of quantification (LOQs) ranged from 0.05 to 0.20 µg/kg and from 0.10 to 0.50 µg/kg, respectively. At spiked levels of 1LOQ, 2LOQ, and 10LOQ, the average recoveries were 79.4%-102.1%, 80.6%-109.5%, and 83.0%-110.6%, respectively, and the relative standard deviations were in the range of 0.8%-16.0%. The low matrix effects of the 15 N-nitrosamines indicated the high sensitivity of the proposed method. The method was applied to detect representative commercial air-dried yak meat samples obtained using different processing techniques. Seven N-nitrosamines, including N-nitrosodimethylamine, N-nitrosodiisobutylamine, N-nitrosodibutylamine, N-methyl-N-phenylnitrous amide, N-ethyl-N-nitrosoaniline, N-nitrosopyrrolidine, and N-nitrosodiphenylamine were detected in all samples. The average contents of the seven N-nitrosamines was 0.08-20.18 µg/kg. The detection rates and average contents of the N-nitrosamines in cooked air-dried yak meat samples were higher than those in traditional raw air-dried yak meat samples. Compared with the manual QuEChERS method, the one-step QuEChERS method developed integrated the extraction and clean-up procedures into one single run, and the detection efficiency was considerably improved. The developed method is simple, rapid, highly sensitive, and insusceptible to human errors. Thus, it is useful for the determination of N-nitrosamines in air-dried yak meat and can be extended to the qualitative and quantitative analysis of N-nitrosamines in other meat products. It also provides method support and a data reference for the general determination of N-nitrosamines, which is of great significance for food safety.


Assuntos
Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Carne , Nitrosaminas , Animais , Nitrosaminas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Bovinos , Contaminação de Alimentos/análise , Carne/análise
3.
Inflamm Bowel Dis ; 30(2): 257-272, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37454278

RESUMO

BACKGROUND: Various extracellular matrix (ECM) reshaping events are involved in inflammatory bowel disease (IBD). LAMB3 is a vital subunit of laminin-332, an important ECM component. Data on the biological function of LAMB3 in intestinal inflammation are lacking. Our aim is to discuss the effect of LAMB3 in IBD. METHODS: LAMB3 expression was assessed in cultured intestinal epithelial cells, inflamed mucosal tissues of patients and mouse colitis models. RNA sequencing, quantitative real-time polymerase chain reaction and Western blotting were used to detect the LAMB3 expression distribution and potential downstream target genes. Dual-luciferase assays and chromatin immunoprecipitation-quantitative polymerase chain reaction were used to determine whether P65 could transcriptionally activate LAMB3 under tumor necrosis factor α stimulation. RESULTS: LAMB3 expression was increased in inflammatory states in intestinal epithelial cells and colonoids and was associated with adverse clinical outcomes in Crohn's disease. Knockdown of LAMB3 inhibited the expression of proinflammatory cytokines. Mechanistically, LAMB3 expression was directly transcriptionally activated by P65 and was inhibited by nuclear factor kappa B inhibitors under tumor necrosis factor α stimulation. Furthermore, RNA sequencing and replenishment experiments revealed that LAMB3 upregulated SERPINA3 to promote intestinal inflammation via the integrin α3ß1/FAK pathway. CONCLUSION: We propose that LAMB3 could serve as a potential therapeutic target of IBD and a predictor of intestinal stenosis of Crohn's disease. Our findings demonstrate the important role of ECM in the progression of IBD and offer an experimental basis for the treatment and prognosis of IBD.


Assuntos
Doença de Crohn , Doenças Inflamatórias Intestinais , Serpinas , Animais , Humanos , Camundongos , Doença de Crohn/patologia , Inflamação/patologia , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Serpinas/metabolismo , Serpinas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
4.
Adv Sci (Weinh) ; 10(32): e2303378, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37786278

RESUMO

Although the MAPK/MEK/ERK pathway is prevalently activated in colorectal cancer (CRC), MEK/ERK inhibitors show limited efficiency in clinic. As a downstream target of MAPK, ELK4 is thought to work primarily by forming a complex with SRF. Whether ELK4 can serve as a potential therapeutic target is unclear and the transcriptional regulatory mechanism has not been systemically analyzed. Here, it is shown that ELK4 promotes CRC tumorigenesis. Integrated genomics- and proteomics-based approaches identified SP1 and SP3, instead of SRF, as cooperative functional partners of ELK4 at genome-wide level in CRC. Serum-induced phosphorylation of ELK4 by MAPKs facilitated its interaction with SP1/SP3. The pathological neoangiogenic factor LRG1 is identified as a direct target of the ELK4-SP1/SP3 complex. Furthermore, targeting the ELK4-SP1/SP3 complex by combination treatment with MEK/ERK inhibitor and the relatively specific SP1 inhibitor mithramycin A (MMA) elicited a synergistic antitumor effect on CRC. Clinically, ELK4 is a marker of poor prognosis in CRC. A 9-gene prognostic model based on the ELK4-SP1/3 complex-regulated gene set showed robust prognostic accuracy. The results demonstrate that ELK4 cooperates with SP1 and SP3 to transcriptionally regulate LRG1 to promote CRC tumorigenesis in an SRF-independent manner, identifying the ELK4-SP1/SP3 complex as a potential target for rational combination therapy.


Assuntos
Neoplasias Colorretais , Regulação da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Neoplasias Colorretais/genética , Carcinogênese/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Elk-4 do Domínio ets/genética , Glicoproteínas
5.
Front Immunol ; 14: 1171380, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529050

RESUMO

The proliferative potential of mast cells after activation for 3-4h was found to be decreased, which suggests that mast cell degranulation and cell proliferation are differentially regulated. ELK4, a member of the ternary complex factor (TCF) subfamily of Ets transcription factors, is one of the downstream effectors of MAPK signaling that is critical for cell proliferation. And Elk4 has been identified to be vital for macrophage activation in response to zymosan and the transcriptional response to 12-O-tetrade canoyl phorbol-13-acetate (TPA) stimulation in fibroblast. However, the effect of ELK4 on the mast cell transcriptional response to FcϵRI and GPCR mediated activation and its potential functional significance in mast cells remain unclear. Here, we showed that ELK4 expression is downregulated in activated mast cells. Elk4 knockout suppresses cell proliferation and impedes the cell cycle in bone marrow-derived mast cells (BMMCs), which is associated with decreased transcription of cell cycle genes. Additionally, the transcriptional activation of cytokines and chemokines is diminished while mast cell degranulation is enhanced in Elk4 knockout BMMCs. Mechanistically, ELK4 might positively modulate Hdc, Ccl3 and Ccl4 transcription by interacting with MITF and negatively regulate the transcription of degranulation-related genes by complexing with SIRT6. Overall, our study identifies a new physiological role of the transcription factor ELK4 in mast cell proliferation and activation.


Assuntos
Citocinas , Mastócitos , Citocinas/metabolismo , Mastócitos/metabolismo , Regulação da Expressão Gênica , Quimiocinas/metabolismo , Transdução de Sinais
6.
Eur J Surg Oncol ; 49(11): 106981, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37455182

RESUMO

BACKGROUND: BRAF V600E mutant-metastatic colorectal cancer (mCRC) is characterized by its short survival time. Treatment approaches vary depending on whether or not the metastases are initially resectable. The benefit of metastasectomy remains unclear, and the optimal first-line treatment is controversial. This study aimed to describe the prognosis of BRAF V600E mutant-mCRC, analyze the recurrence pattern in resectable patients, and explore the optimal first-line treatment for unresectable patients. METHODS: Patients diagnosed with BRAF V600E mutant-mCRC between February 2014 and January 2022 in five hospitals were enrolled. Date on clinical and pathological characteristics, treatment features, and survival outcomes were collected. RESULTS: Of the 220 included patients, 64 initially resectable patients had a significantly longer overall survival (OS) (37.07 vs. 20.20 months, P < 0.001) than initially unresectable patients. Of 156 unresectable patients, 54 received doublet (FOLFOX, XELOX or FOLFIRI) or triplet (FOLFOXIRI) chemotherapies (Chemo), 55 received Chemo plus Bevacizumab (Chemo+Bev), and 33 received vemurafenib plus cetuximab and irinotecan (VIC). The VIC regimen had a better progression-free survival (PFS) (12.70 months) than the Chemo (6.70 months, P < 0.001) and Chemo+Bev (8.8 months, P = 0.044) regimens. Patients treated with VIC had the best overall response rate (60.16%, P < 0.001), disease control rate (93.94%, P < 0.001) and conversional resection rate (24.24%, P = 0.003). CONCLUSIONS: Metastasectomy is beneficial to the survival of patients with BRAF V600E mutant-mCRC. For initially unresectable patients, VIC as first-line therapy is associated with a better prognosis and efficacy than doublet and triplet chemotherapy with or without bevacizumab.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Bevacizumab/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Colorretais/terapia , Neoplasias Colorretais/tratamento farmacológico , Irinotecano , Neoplasias do Colo/tratamento farmacológico , Neoplasias Retais/tratamento farmacológico , Cetuximab/uso terapêutico , Vemurafenib/uso terapêutico , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica , Fluoruracila , Leucovorina
7.
Int Orthop ; 47(3): 781-791, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36348088

RESUMO

PURPOSE: Kashin-Beck disease (KBD) is an endemic osteoarthropathy affecting the epiphyseal growth plate of multiple joints in young and adolescent patients. Previous studies have focused on the visible deformed extremities instead of the spinal radiological features, especially the atlantoaxial joint. The aim of this study was to determine the prevalence and radiographic features of atlantoaxial dislocation (AAD) in adult patients with KBD. METHODS: This study was conducted on KBD patients in three typical endemic counties between October 2017 and November 2019. The patients were evaluated by collecting basic information, clinical signs and symptoms. They underwent dynamic cervical radiography, by which AAD was diagnosed. For those patients with confirmed or suspected AAD, computed tomography (CT) imaging was performed to observe the odontoid morphology and degenerative changes in the lateral atlantoaxial joints. Radiographic evaluations were reviewed to determine the prevalence and features of AAD. RESULTS: A total of 39 (14.6%) of 267 KBD patients were diagnosed with AAD. Compared with the non-AAD patients, the detection rate of AAD was associated with a longer disease duration and stage and was not associated with age, sex or BMI. Thirty-two patients had symptoms at the neck or neurological manifestations, while seven had no symptoms. There were three types of morphologies of the odontoid process in AAD patients: separating in 19 cases, hypoplastic in 15 cases and intact in five cases. Anterior dislocation was noted in 29 cases, and posterior dislocation was noted in ten cases. Thirty-four cases were reducible, and five were irreducible. The lateral atlantoaxial joints had different severities of degenerative changes in 17 cases. CONCLUSIONS: This study revealed that the prevalence of AAD was 14.6% in adult KBD patients. The radiographic features of AAD include manifestations of odontoid dysplasia and chronic degenerative changes in atlantoaxial joints. KBD patients with severe stages and longer disease duration were more vulnerable to the occurrence of AAD. We postulate that this atlantoaxial anomaly might originate from chondronecrosis of the epiphyseal growth plate of the odontoid process in young and adolescent individuals. This study may provide a clinical reference to help clinicians screen, prevent and treat AAD in adult patients with KBD.


Assuntos
Articulação Atlantoaxial , Luxações Articulares , Doença de Kashin-Bek , Adolescente , Humanos , Adulto , Doença de Kashin-Bek/complicações , Prevalência , Radiografia , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/epidemiologia , Luxações Articulares/complicações , Tomografia Computadorizada por Raios X , Articulação Atlantoaxial/diagnóstico por imagem
8.
Nat Commun ; 13(1): 4995, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008411

RESUMO

Dysregulation of Hippo pathway leads to hyperactivation of YAP-TEAD transcriptional complex in various cancers, including colorectal cancer (CRC). In this study, we observed that HHEX (Hematopoietically expressed homeobox) may enhance transcription activity of the YAP-TEAD complex. HHEX associates with and stabilizes the YAP-TEAD complex on the regulatory genomic loci to coregulate the expression of a group of YAP/TEAD target genes. Also, HHEX may indirectly regulate these target genes by controlling YAP/TAZ expression. Importantly, HHEX is required for the pro-tumorigenic effects of YAP during CRC progression. In response to serum stimulation, CK2 (Casein Kinase 2) phosphorylates HHEX and enhances its interaction with TEAD4. A CK2 inhibitor CX-4945 diminishes the interaction between HHEX and TEAD4, leading to decreased expression of YAP/TEAD target genes. CX-4945 synergizes the antitumor activity of YAP-TEAD inhibitors verteporfin and Super-TDU. Elevated expression of HHEX is correlated with hyperactivation of YAP/TEAD and associated with poor prognosis of CRC patients. Overall, our study identifies HHEX as a positive modulator of YAP/TEAD to promote colorectal tumorigenesis, providing a new therapeutic strategy for targeting YAP/TEAD in CRC.


Assuntos
Caseína Quinase II , Neoplasias Colorretais , Fatores de Transcrição de Domínio TEA/metabolismo , Proteínas de Sinalização YAP/metabolismo , Carcinogênese , Caseína Quinase II/genética , Caseína Quinase II/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Proteínas Musculares/metabolismo , Fatores de Transcrição/metabolismo
9.
Front Oncol ; 11: 657210, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026633

RESUMO

BACKGROUND: Amine oxidase copper containing 1 (AOC1) is a gene whose biological function in colorectal cancer (CRC) has not been elucidated. Therefore, the purpose of this study was to investigate the clinical significance of AOC1 expression in CRC and its biological function in CRC cell lines. MATERIALS AND METHODS: AOC1 expression levels were examined in paired CRC and peritumoral tissues, and distant liver metastatic tissues were examined using quantitative real-time PCR, western blotting, and immunohistochemistry staining. The log-rank test and Cox regression model were used to analyze the relationship between AOC1 expression and prognosis. Proliferation assays (Cell Counting Kit-8 and colony formation assays), migration assays (Transwell and wound healing assays) and xenograft tumor formation in nude mice were performed to assess the biological role of AOC1 in CRC cells. RESULTS: AOC1 expression significantly increased in human CRC tissues, especially in liver metastases, and was associated with a worse prognosis. In addition, AOC1 had higher expression in tumor organoids than in normal organoids, suggesting that it was highly expressed in the tumor epithelium. Functional analysis demonstrated that AOC1 knockdown inhibited the proliferation and migration of CRC cells by inducing EMT in vitro. Xenograft tumor formation in nude mice showed that knockdown of AOC1 inhibited the tumor xenografts growth in vivo. CONCLUSION: High expression of AOC1 was significantly associated with worse clinical outcomes, was an independent risk factor for poor prognosis, and promoted aggressive CRC cell phenotypes. AOC1 is expected to become a novel biomarker for predicting the prognosis of patients with CRC and an effective therapeutic target in clinical practice.

10.
Biochim Biophys Acta Mol Basis Dis ; 1866(12): 165923, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800944

RESUMO

OBJECTIVE: Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality. The bromodomain and extra-terminal domain (BET) inhibitors suppresses the gene expressions of various oncogenes and shows a good efficacy in the preclinical CRC models. We investigate the mechanism of action of BET inhibitors in CRC. METHODS: The effect of BET inhibitor (JQ1) on the HGF-MET signaling was assessed by qPCR, western blot and immunohistochemical staining in CRC and cancer-associated fibroblasts (CAFs). The effect of JQ1 on the CAFs was investigated using the primary CAFs derived from CRC tissues and induced-CAFs derived from isolating foreskin fibroblasts. The effect of JQ1 on the gene expression profile of CAFs was explored by RNA-sequence, qPCR and bioinformatic analysis. RESULTS: JQ1 decreased the mRNA and protein levels of MET in CRC cells and downregulated the mRNA and protein levels of HGF in both CRC cells and CAFs. JQ1 attenuated the pro-migratory activity of CAFs through downregulation of HGF expression in CAFs. Meanwhile, JQ1 also reduced the ability of contracting collagen gels, decreased the cell proliferation, induced G1 arrest and repressed the pro-inflammatory gene expressions in CAFs. MYC expression was suppressed by JQ1 in CAFs. Knockdown of MYC induced G1 arrest in CAFs. CONCLUSION: Our results demonstrate the inhibitory effect of BET inhibition on the HGF-MET signaling and the pro-tumor activity of CAFs, revealing a new mechanism by which BET inhibition suppresses CRC progression.


Assuntos
Antineoplásicos/farmacologia , Azepinas/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Fibroblastos/efeitos dos fármacos , Fator de Crescimento de Hepatócito/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Triazóis/farmacologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/metabolismo , Fibroblastos/patologia , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
11.
Theranostics ; 10(13): 5845-5864, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32483423

RESUMO

Colorectal cancer (CRC) is the leading cause of cancer death; however, targets with broad anti-CRC effects are limited. Sirtuin6 (SIRT6) is a conserved nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase that is widely pathologically downregulated in CRC, but its pharmacological effect in CRC remains undefined due to the lack of small-molecule SIRT6 activators. We searched for a compound activating SIRT6 and investigated its anti-CRC effect in various models. Methods: We identified an allosteric SIRT6 activator, MDL-811. Its ability to enhance SIRT6 deacetylation at protein and cellular levels was evaluated by Fluor de Lys (FDL) and western blots. We assessed the proliferation of 26 CRC cell lines and patient-derived organoids (PDOs) treated with MDL-811. In vivo efficacy of MDL-811 was evaluated in HCT116 cell line- and patient-derived xenografts as well as a spontaneous CRC model. RNA sequencing and real-time quantitative PCR assays were performed to analyze gene expression changes in MDL-811-treated HCT116 cells. Along with controls in SIRT6-overexpressing HCT116 cells, the SIRT6-mediated histone H3 deacetylation at the Cytochrome P450 family 24 subfamily A member 1 (CYP24A1) gene locus was assessed by chromatin immunoprecipitation (ChIP) in MDL-811-treated HCT116 cells. A combination therapy against CRC based on the downstream gene of SIRT6 activation was evaluated in cells and mouse models. Results: MDL-811 significantly activated SIRT6 histone H3 deacetylation (H3K9Ac, H3K18Ac, and H3K56Ac) in vitro and had broad antiproliferative effects on diverse CRC cell lines and PDOs. More importantly, the in vivo anti-tumor efficacy of MDL-811 was demonstrated across cell line- and patient-derived xenografts and in the APCmin/+ spontaneous CRC model. Mechanically, we identified a new downstream target gene of SIRT6 in CRC, CYP24A1. Based on these findings, a combination drug strategy with MDL-811 to synergistically enhance the anti-CRC effect of vitamin D3 was validated in vitro and in vivo. Conclusions: Our data provide proof of concept that targeting SIRT6 using a small-molecule activator is an attractive therapeutic strategy for CRC and that MDL-811 could be a promising lead compound for further preclinical and clinical studies of treatments for CRC.


Assuntos
Colecalciferol/farmacologia , Neoplasias Colorretais/metabolismo , Sirtuínas/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colecalciferol/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Ativadores de Enzimas/farmacologia , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Sirtuínas/farmacologia , Sirtuínas/fisiologia , Bibliotecas de Moléculas Pequenas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Oncogene ; 39(24): 4666-4680, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32398865

RESUMO

Aberrant expression of laminin-332 promotes tumour growth and metastasis in multiple cancers. However, the dysregulated expression and mechanism of action of LAMB3, which encodes the ß3 subunit of laminin-332, and the mechanism underlying dysregulated LAMB3 expression in CRC remain obscure. Here, we show that LAMB3 is overexpressed in CRC and that this overexpression is correlated with tumour metastasis and poor prognosis. Overexpression of LAMB3 promoted cell proliferation and cell migration in vitro and tumour growth and metastasis in vivo, while knockdown of LAMB3 elicited opposing effects. LAMB3 inhibited the tumour suppressive function of FOXO3/4 by activating AKT in CRC. Both the BET inhibitor JQ1 and the MEK inhibitor U0126 decreased the mRNA level of LAMB3 in multiple CRC cells. Mechanistically, ELK4 cooperated with BRD2 to regulate the transcription of LAMB3 in CRC by directly binding to the ETS binding motifs in the LAMB3 promoter. ELK4 was as acetylated at K125, which enhanced the interaction between ELK4 and BRD2. JQ1 disrupted the interaction between ELK4 and BRD2, resulting in decreased binding of BRD2 to the LAMB3 promoter and downregulation of LAMB3 transcription. Both ELK4 and BRD2 expression was associated with LAMB3 expression in CRC. LAMB3 expression was also negatively correlated with FOXO3/4 in CRC. Our study reveals the pro-tumorigenic role of LAMB3 through the AKT-FOXO3/4 axis and the transcriptional mechanism of LAMB3 in CRC, demonstrating that LAMB3 is a potential therapeutic target that can be targeted by BET inhibitors and MEK inhibitors.


Assuntos
Moléculas de Adesão Celular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias Colorretais/metabolismo , Proteína Forkhead Box O3/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Proteínas Elk-4 do Domínio ets/metabolismo , Acetilação , Animais , Moléculas de Adesão Celular/genética , Proteínas de Ciclo Celular/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Proteína Forkhead Box O3/genética , Fatores de Transcrição Forkhead/genética , Humanos , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-akt/genética , Fatores de Transcrição/genética , Proteínas Elk-4 do Domínio ets/genética , Calinina
13.
Mucosal Immunol ; 12(6): 1291-1303, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31481750

RESUMO

Alpha B-crystallin (CRYAB) is an important member of the small heat shock protein family, and plays a protective and therapeutic role in neurological inflammation. CRYAB expression was assessed in cultured HT29 and Caco-2 cells and inflamed mucosa of patients with inflammatory bowel disease (IBD) and colitis models in mice. Lentivirus-overexpressing and CRSIPR/Cas9 systems were used in different cells to upregulate and silence CRYAB expression, respectively. Cell permeable recombined fusion protein TAT-CRYAB was injected intraperitoneally into dextran sulfate sodium (DSS)- or 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice to assess its anti-inflammatory effects. CRYAB was found to be significantly decreased in the inflamed mucosa from IBD patients and DSS-induced colitis in mice, and negatively correlated with the levels of TNF-α and IL-6, respectively. Enforced expression of CRYAB suppressed expression of proinflammatory cytokines (e.g., TNF-α, IL-6, IL-1ß, and IL-8) via inhibiting the IKK complex formation, whereas lack of CRYAB expression markedly enhanced proinflammatory responses. Consistently, administration of TAT-CRYAB fusion protein significantly alleviated DSS- or TNBS-induced colitis in mice and protected intestinal barrier integrity. CRYAB regulates inflammatory response in intestinal mucosa by inhibiting IKKß-mediated signaling and may serve as a novel therapeutic approach in the treatment of IBD.


Assuntos
Colite Ulcerativa/metabolismo , Colo/metabolismo , Doença de Crohn/metabolismo , Quinase I-kappa B/metabolismo , Mucosa Intestinal/metabolismo , Cadeia B de alfa-Cristalina/metabolismo , Animais , Células CACO-2 , Estudos de Casos e Controles , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Colite Ulcerativa/prevenção & controle , Colo/patologia , Doença de Crohn/genética , Doença de Crohn/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Quinase I-kappa B/genética , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Células THP-1 , Cadeia B de alfa-Cristalina/genética
14.
DNA Cell Biol ; 38(6): 541-548, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31140864

RESUMO

The aim of this research was to verify the mutation rate of the ring finger protein 43 (RNF43) of the transmembrane E3 ubiquitin ligase and investigate the influence of single nucleotide polymorphisms (SNPs) rs2257205 in RNF43 in a Chinese colorectal cancer (CRC) cohort. DNA from 177 diagnosed CRC patients' tissues or blood samples were extracted, amplified, and sequenced. Clinicopathological features, including age, gender, tumor location, tumor-lymph node-metastasis stage, and survival information, were analyzed. Four novel RNF43 mutations (including G659 and R117 sites) were validated in 177 CRC patients; all events were somatic frameshift mutations. Furthermore, we also found that an SNP (rs2257205) of the RNF43 X117 site was associated with overall survival (OS) instead of disease-free survival. G homozygote subjects were significantly correlated with poor OS compared with another group. Then we rescued RNF43 R117R (encoded by nucleotide CGC) and R117H (encoded by nucleotide CAC) expression in the HCT116 cells and analyzed the targets of the Wnt/ß-catenin pathway. The expression of CCND1 and c-Myc were decreased. The prognosis of CRC patients could be affected by the different functions of SNPs of RNF43.


Assuntos
Neoplasias Colorretais/mortalidade , Proteínas de Ligação a DNA/genética , Proteínas Oncogênicas/genética , Polimorfismo de Nucleotídeo Único , Idoso , Linhagem Celular Tumoral , China , Estudos de Coortes , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Prognóstico , Estudos Retrospectivos , Ubiquitina-Proteína Ligases
15.
Cell Death Dis ; 9(3): 315, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29472532

RESUMO

The bromodomain and extra-terminal domain inhibitors (BETi) are promising epigenetic drugs for the treatment of various cancers through suppression of oncogenic transcription factors. However, only a subset of colorectal cancer (CRC) cells response to BETi. We investigate additional agents that could be combined with BETi to overcome this obstacle. JQ1-resistant CRC cells were used for screening of the effective combination therapies with JQ1. RNA-seq was performed to explore the mechanism of synergistic effect. The efficacy of combinational treatment was tested in the CRC cell line- and patient-derived xenograft (PDX) models. In BETi-sensitive CRC cells, JQ1 also impaired tumor angiogenesis through the c-myc/miR-17-92/CTGF+THBS1 axis. CTGF knockdown moderately counteracted anti-angiogenic effect of JQ1 and led to partially attenuated tumor regression. JQ1 decreased c-myc expression and NF-κB activity in BETi-sensitive CRC cells but not in resistant cells. Bortezomib synergistically sensitized BETi-resistant cells to the JQ1 treatment, and JQ1+Bortezomib induced G2/M arrest in CRC cells. Mechanistically, inhibition of NF-κB by Bortezomib or NF-κB inhibitor or IKK1/2 siRNA all rendered BETi-resistant cells more sensitive to BETi by synergistic repression of c-myc, which in turn induces GADD45s' expression, and by synergistic repression of FOXM1 which in turn inhibit G2/M checkpoint genes' expression. Activation of NF-κB by IκBα siRNA induced resistance to JQ1 in BETi-sensitive CRC cells. Last, JQ1+Bortezomib inhibited tumor growth and angiogenesis in CRC cell line xenograft model and four PDX models. Our results indicate that anti-angiogenic effect of JQ1 plays a vital role in therapeutic effect of JQ1 in CRC, and provide a rationale for combined inhibition of BET proteins and NF-κB as a potential therapy for CRC.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Proteína Forkhead Box M1/genética , NF-kappa B/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteína Oncogênica p55(v-myc)/genética , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Azepinas/administração & dosagem , Bortezomib/administração & dosagem , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/fisiopatologia , Sinergismo Farmacológico , Feminino , Proteína Forkhead Box M1/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , NF-kappa B/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína Oncogênica p55(v-myc)/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Triazóis/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Crohns Colitis ; 12(5): 546-558, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29370346

RESUMO

BACKGROUND AND AIMS: The association between thiopurines and colorectal neoplasia risk remains controversial in inflammatory bowel disease [IBD] patients. We performed a systematic review and meta-analysis examining this association. METHODS: A comprehensive search of the PubMed, EMBASE and Cochrane Library databases was performed to identify relevant literature. Random-effects models were applied to calculate the pooled odds ratio [OR] and relative risk [RR] with corresponding 95% confidence intervals [CIs] among case-control and cohort studies. RESULTS: Eleven cohort and 16 case-control studies involving 95397 patients were included in this study. Overall, the use of thiopurines was associated with a reduced risk of colorectal neoplasia both in case-control [OR = 0.49, 95% CI: 0.34-0.70] and cohort studies [RR = 0.96, 95% CI: 0.94-0.98]. Moreover, a protective effect of thiopurines against advanced neoplasia [high-grade dysplasia and cancer] [OR = 0.51, 95% CI: 0.31-0.84 for case-control studies; RR = 0.96, 95% CI: 0.94-0.98 for cohort studies] and colorectal cancer [CRC] [OR = 0.56, 95% CI: 0.34-0.93 for case-control studies; RR = 0.96, 95% CI: 0.94-0.98 for cohort studies] was also observed. Furthermore, when the analysis was conducted on patients at a high risk for colorectal neoplasia, the chemopreventive effect was confirmed in patients with long disease duration [> 8 years] but not in those with extensive colitis or primary sclerosing cholangitis. CONCLUSIONS: This study demonstrated that thiopurine use was associated with a reduced risk of colorectal neoplasia, advanced neoplasia and CRC in IBD patients, especially those with long disease duration [> 8 years].


Assuntos
Neoplasias Colorretais/epidemiologia , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mercaptopurina/análogos & derivados , Mercaptopurina/uso terapêutico , Neoplasias Colorretais/etiologia , Humanos , Incidência , Doenças Inflamatórias Intestinais/complicações , Fatores de Proteção , Fatores de Risco
17.
Gastroenterol Res Pract ; 2016: 5037254, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27057160

RESUMO

Background. Functional dyspepsia (FD) is a functional upper gastrointestinal disorder with significant morbidity and medical costs. Previous studies investigated the association of G-protein ß3 (GNB3) genetic polymorphisms with FD but with inconsistent results. Therefore, we performed a meta-analysis to derive a precise estimation of the relationship between GNB3 polymorphisms and FD. Methods. We searched different databases including PubMed, EMBASE, CNKI, and the Ovid Library to gather eligible studies on GNB3 polymorphisms and FD. The association was assessed by the odds ratio (OR) with 95% confidence intervals (CI). Results. We identified 12 studies with 1109 cases and 2853 controls for the analysis. We found no associations of GNB3 C825T polymorphism with FD in the overall population (T versus C, OR = 1.06, 95% CI: 0.96-1.18, P = 0.26; TT versus CC + CT, OR = 1.16, 95% CI: 0.97-1.39, P = 0.11; TT + CT versus CC, OR = 1.01, 95% CI: 0.77-1.31, P = 0.96; TT versus CC, OR = 1.15, 95% CI: 0.93-1.44, P = 0.20). Subgroup analyses by genotyping method indicated that the magnitude of association was strengthened for additive model (OR = 1.15, 95% CI: 1.07-2.24, P = 0.02). Sensitivity analysis did not reveal significant associations under all models. Conclusions. This meta-analysis demonstrates that GNB3 C825T polymorphism may not be a risk factor for FD.

18.
Exp Ther Med ; 10(5): 1759-1767, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26640547

RESUMO

BK polyomavirus (BKV) is important pathogen for kidney transplant recipients, as it is frequently re-activated, leading to nephropathy. The aim of this study was to investigate the phylogenetic reconstruction and polymorphism of the VP2 gene in BKV isolated from Chinese kidney transplant recipients. Phylogenetic analysis was carried out in the VP2 region from 135 BKV-positive samples and 28 reference strains retrieved from GenBank. The unweighted pair-group method with arithmetic mean (UPGMA) grouped all strains into subtypes, but failed to subdivide strains into subgroups. Among the plasma and urine samples, all plasma (23/23) and 82 urine samples (82/95) were identified to contain subtype I; the other 10 urine samples contained subtype IV. A 86-bp fragment was identified as a highly conserved sequence. Following alignment with 36 published BKV sequences from China, 92 sites of polymorphism were identified, including 11 single nucleotide polymorphisms (SNPs) prevalent in Chinese individuals and 30 SNPs that were specific to the two predominant subtypes I and IV. The limitations of the VP2 gene segment in subgrouping were confirmed by phylogenetic analysis. The conserved sequence and polymorphism identified in this study may be helpful in the detection and genotyping of BKV.

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