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1.
Semin Cancer Biol ; 80: 73-86, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32088363

RESUMO

Colorectal cancer (CRC) is one of most common malignancies worldwide and its incidence is still growing. In spite of recent advances in targeted therapies, their clinical efficacy has been limited, non-curative and unaffordable. A growing body of literature indicates that CRC is a multi-modal disease, where a variety of factors within the tumor microenvironment play a significant role in its pathogenesis. For instance, imbalance in gut microbial profiles and impaired intestinal barrier function contribute to the overall intestinal inflammation and initiation of CRC. Moreover, persistent chronic inflammation favors a tumor microenvironment for the growth of cancer. In addition, autophagy or 'self-eating' is a surveillance mechanism involved in the degradation of cellular constituents that are generated under stressful conditions. Cancer stem cells (CSCs), on the other hand, engage in the onset of CRC and are able to endow cancer cells with chemo-resistance. Furthermore, the aberrant epigenetic alterations promote CRC. These evidences highlight the need for multi-targeted approaches that are not only safe and inexpensive but offer a more effective alternative to current generation of targeted drugs. Curcumin, derived from the plant Curcuma longa, represents one such option that has a long history of its use for a variety of chronic disease including cancer, in Indian ayurvedic and traditional Chinese medicine. Scientific evidence over the past few decades have overwhelmingly shown that curcumin exhibits a multitude of anti-cancer activities orchestrated through key signaling pathways associated with cancer. In this article, we will present a current update and perspective on this natural medicine - incorporating the basic cellular mechanisms it effects and the current state of clinical evidence, challenges and promise for its use as a cancer preventative and potential adjunct together with modern therapies for CRC patients.


Assuntos
Neoplasias Colorretais , Curcumina , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/patologia , Curcumina/farmacologia , Curcumina/uso terapêutico , Epigenômica , Humanos , Inflamação/tratamento farmacológico , Transdução de Sinais , Microambiente Tumoral
2.
Anal Chem ; 95(36): 13401-13406, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37565811

RESUMO

Assays for the molecular detection of miRNAs are typically constrained by the level of multiplexing, especially in a single tube. Here, we report a general and programmable diagnostic platform by combining mesophilic Clostridium perfringens Argonaute (CpAgo) with exponential isothermal amplification (EXPAR), which is a dual-signal amplification strategy, allowing for the rapid and sensitive detection of multiple miRNAs with single-nucleotide discrimination in one pot. The CpAgo-based One-Pot (COP) assay achieved a limit of detection of 1 zM miRNA within 30 min of turnaround time and a wide concentration range. This COP assay was applied to simultaneously detect four miRNAs in a single tube from clinical serum samples, showing superior analytical performance in distinguishing colorectal cancer patients from healthy individuals. This programmable, one-pot, multiplex, rapid, and specific strategy offers great promise in scientific research and clinical applications.


Assuntos
MicroRNAs , Humanos , MicroRNAs/genética , Clostridium perfringens/genética , Nucleotídeos , Técnicas de Amplificação de Ácido Nucleico
3.
Anal Chem ; 95(26): 10025-10033, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37343158

RESUMO

Exosomes are small extracellular vesicles that can be utilized as noninvasive biomarkers for diagnosis and treatment of cancer and other diseases. This study reports on a strategy involving a hybridized chain reaction-amplified chain coupled with an alkaline phosphatase-induced Ag-shell nanostructure for the ultrasensitive and rapid surface-enhanced Raman scattering immunoassay of exosomes. Exosomes from prostate cancer were captured using prostate-specific membrane antigen aptamer-modified magnetic beads; then, the hybridized chain reaction-amplified chain was released, incorporating a large number of functional moieties with signal amplification effects. Moreover, the steps of traditional immunoassay were simplified using magnetic materials, and the rapid, sensitive, and accurate detection of exosomes was achieved. Results could be obtained within 40 min with a detection limit of 19 particles/µL. Furthermore, the sera of human prostate cancer patients could be easily distinguished from those of healthy controls, highlighting the potential use of exosome analysis in clinical diagnostics.


Assuntos
Exossomos , Nanoestruturas , Neoplasias da Próstata , Masculino , Humanos , Fosfatase Alcalina/análise , Exossomos/química , Análise Espectral Raman , Neoplasias da Próstata/diagnóstico , Imunoensaio/métodos
4.
Anal Chem ; 94(32): 11290-11297, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35894425

RESUMO

The simultaneous analysis of the levels of multiple microRNAs (miRNAs) is critical to the early diagnosis of cancer. However, this analysis is challenging because of the low concentrations of miRNAs and their high sequence homology. Here, we report a general and programmable diagnostic strategy for miRNA analysis: Thermus thermophilus Argonaute (TtAgo)-assisted exponential isothermal amplification for multiplex detection (TEAM). This system combines exponential isothermal amplification (EXPAR), for target amplification, with programmable TtAgo cleavage, for the generation of the reporting signal. The TEAM assay achieved attomolar sensitivity with a rapid turnaround time (30-35 min). Because of the single-nucleotide precision of TtAgo, the system demonstrated robust multiplex capability in the simultaneous detection of four miRNA targets and the classification of let-7 family members. The TEAM assay was superior in differentiating colorectal cancer patients from healthy individuals relative to the conventional EXPAR and reverse transcription polymerase chain reaction (RT-PCR) methods. This tunable and scalable approach is a powerful nucleic acid analysis tool that holds promise in scientific and clinical applications.


Assuntos
MicroRNAs , Neoplasias , Proteínas Argonautas/genética , Humanos , MicroRNAs/análise , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Thermus thermophilus/genética
5.
FASEB J ; 34(9): 11900-11912, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32741018

RESUMO

Lung cancer is one of most common malignancies worldwide. We have previously identified retinoic acid-induced gene G (Rig-G) as a tumor suppressor in not only acute promyelocytic leukemia, but also in other solid tumors. However, the clinical significance of Rig-G and the underlying mechanism(s) for its biological function in lung cancer remain largely unexplored. Herein, we first compared the expression of Rig-G between lung cancer (n = 138) and normal tissues (n = 23), from public-available data sets and our patient cohort. We further analyzed the correlation of Rig-G expression with key clinico-pathological features and survival outcomes in a multi-site clinical cohort of 300 lung cancer patients. Functional studies for Rig-G were performed in cell lines, and an animal model to support clinical findings. We found that Rig-G was frequently downregulated in lung cancer tissues and cell lines, and correlated with poor prognosis in lung cancer patients. Overexpression of Rig-G led to significantly reduced cell growth and suppressed migration in A549 and NCI-H1944 cells, accompanied by reduced epithelial-mesenchymal transition. Likewise, restoration of Rig-G in Lewis lung carcinoma cells permitted development of fewer cancer metastases versus controls in an animal model. Gene expression profiling results identified p53 pathway as a key downstream target of Rig-G, and p53 inhibition by pifithrin-α caused abrogation of tumor-suppressive effects of Rig-G in lung cancer. In conclusion, we, for the first time, have identified Rig-G as a novel and important tumor suppressor, which may serve as a potential therapeutic target for restoring p53 expression in lung cancer patients.


Assuntos
Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Neoplasias Pulmonares/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/biossíntese , Células A549 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Proteína Supressora de Tumor p53/genética
6.
Mikrochim Acta ; 188(9): 307, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34453211

RESUMO

Currently, the determination of DNA methylation is still a challenge due to the limited efficiency of enrichment, bisulfite modification, and detection. In this study, a dual-modality loop-mediated isothermal amplification integrated with magnetic bead isolation is  proposed for the determination of methylated Septin9 gene in colorectal cancer. Magnetic beads modified with anti-methyl cytosine antibody were prepared for fast enrichment of methylated DNA through specific immunoaffinity (30 min). One-pot real-time fluorescence and colorimetric loop-mediated isothermal amplification were simultaneously developed for detecting methylated Septin9 gene (60 min). The real-time fluorescence generating by SYTO-9 dye (excitation: 470 nm and emission: 525 nm) and pH indicator (neutral red) was used for quantitative and visualized detection of methylated DNA. This method was demonstrated to detect methylated DNA from HCT 116 cells ranging from 2 to 0.02 ng/µL with a limit of detection of 0.02 ± 0.002 ng/µL (RSD: 9.75%). This method also could discriminate methylated Septin9 in 0.1% HCT 116 cells (RSD: 6.60%), suggesting its high specificity and sensitivity. The feasibility of this assay was further evaluated by clinical plasma samples from 20 colorectal cancer patients and 20 healthy controls, which shows the potential application in simple, low cost, quantitative, and visualized detection of methylated nucleic acids. A dual-modality loop-mediated isothermal amplification (LAMP) integrated with immuno-magnetic beads (IMB) enrichment was proposed for the determination of methylated Septin9 gene in colorectal cancer (CRC).


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Colorretais/diagnóstico , Metilação de DNA , DNA/sangue , Septinas/genética , Biomarcadores Tumorais/química , Linhagem Celular Tumoral , Neoplasias Colorretais/sangue , Colorimetria , DNA/química , Corantes Fluorescentes/química , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Compostos Orgânicos/química , Espectrometria de Fluorescência
7.
Anal Bioanal Chem ; 411(26): 6877-6887, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31388715

RESUMO

The increasing threat of Streptococcus gallolyticus subsp. gallolyticus (SGG) infections has gained considerable attention for its strong association with colorectal cancer (CRC). Herein, we proposed real-time fluorescence loop-mediated isothermal amplification (LAMP) as a novel, simple, rapid, and highly sensitive assay for identifying SGG for the first time. This assay was capable of detecting SGG with initial DNA concentrations ranging from 102 to 108 copies per microliter, under isothermal conditions within 30 min via real-time fluorescence monitoring. Our method was tested for specific identification of SGG strains without cross-reaction with other Streptococcus gallolyticus subspecies and Escherichia coli. The developed LAMP shows a superior performance with shorter time and higher sensitivity compared with conventional polymerase chain reaction (PCR). Significantly, this proposed approach was successfully applied for detecting SGG in clinical urine samples, which is non-invasive diagnosis, showing excellent accuracy and reliability to discriminate healthy controls and CRC patients. For comparison, these samples were also tested against PCR assay. These results yielded an analytical sensitivity of 100% and a specificity of 100% for SGG testing using LAMP. The findings suggest LAMP can be employed for detecting SGG infections which is useful for diagnosis and screening of CRC.


Assuntos
Neoplasias Colorretais/microbiologia , DNA Bacteriano/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Streptococcus gallolyticus subspecies gallolyticus/genética , Adulto , Idoso , Neoplasias Colorretais/urina , DNA Bacteriano/isolamento & purificação , Feminino , Fluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico/economia , Streptococcus gallolyticus subspecies gallolyticus/isolamento & purificação , Fatores de Tempo
8.
Mol Cancer ; 17(1): 16, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382334

RESUMO

BACKGROUND: Emerging evidence suggests that PIWI-interacting RNAs (piRNAs) may be important epigenetic regulators of gene expression in human cancers; however, their functional and clinical significance in colorectal cancer (CRC) remains unknown. METHODS: We performed piRNA expression profiling in paired cancer and normal tissues through small RNA-sequencing. The clinical significance of candidate piRNAs was investigated, and independently validated in 771 CRC patients from three independent cohorts. The biological function of piRNAs was characterized in cell lines, followed by identification and validation of downstream target genes in CRC tissues. RESULTS: We identified piR-1245 as a novel and frequently overexpressed noncoding RNA in CRC, and its expression significantly correlated with advanced and metastatic disease. Patients with high piR-1245 expression experienced significantly shorter overall survival, and multivariate analysis identified its expression to serve as an independent prognostic biomarker in CRC. Functionally, piR-1245 acts as an oncogene and promotes tumor progression, and gene expression profiling results identified a panel of downstream target-genes involved in regulating cell survival pathway. Based upon piRNA:mRNA sequence complementarity, we identified a panel of tumor suppressor genes (ATF3, BTG1, DUSP1, FAS,NFKBIA, UPP1, SESN2, TP53INP1 and MDX1) as direct targets of piR-1245, and successfully validated an inverse correlation between their expression and piR-1245 in CRC. CONCLUSIONS: We for the first time have identified the role for a PIWI-interacting noncoding RNA, piR-1245, as a novel oncogene and a potential prognostic biomarker in colorectal cancer.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Oncogenes , RNA Interferente Pequeno , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Morte Celular/genética , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Interferência de RNA
9.
Gastroenterology ; 152(4): 851-866.e24, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27876571

RESUMO

BACKGROUND & AIMS: Nearly 20% of the global cancer burden can be linked to infectious agents. Fusobacterium nucleatum promotes tumor formation by epithelial cells via unclear mechanisms. We aimed to identify microRNAs (miRNAs) induced by F nucleatum and evaluate their ability to promote colorectal carcinogenesis in mice. METHODS: Colorectal cancer (CRC) cell lines were incubated with F nucleatum or control reagents and analyzed in proliferation and would healing assays. HCT116, HT29, LoVo, and SW480 CRC cell lines were incubated with F nucleatum or phosphate-buffered saline (PBS [control]) and analyzed for miRNA expression patterns and in chromatin immunoprecipitation assays. Cells were incubated with miRNAs mimics, control sequences, or small interfering RNAs; expression of reporter constructs was measured in luciferase assays. CRC cells were incubated with F nucleatum or PBS and injected into BALB/C nude mice; growth of xenograft tumors was measured. C57BL adenomatous polyposis colimin/+, C57BL miR21a-/-, and C57BL mice with full-length miR21a (controls) were given F nucleatum by gavage; some mice were given azoxymethane and dextran sodium sulfate to induce colitis and colon tumors. Intestinal tissues were collected and tumors were counted. Serum samples from mice were analyzed for cytokine levels by enzyme-linked immunosorbent assay. We performed in situ hybridization analyses to detect enrichment of F nucleatum in CRC cells. Fusobacterium nucleatum DNA in 90 tumor and matched nontumor tissues from patients in China were explored for the expression correlation analysis; levels in 125 tumor tissues from patients in Japan were compared with their survival times. RESULTS: Fusobacterium nucleatum increased proliferation and invasive activities of CRC cell lines compared with control cells. CRC cell lines infected with F nucleatum formed larger tumors, more rapidly, in nude mice than uninfected cells. Adenomatous polyposis colimin/+ mice gavaged with F nucleatum developed significantly more colorectal tumors than mice given PBS and had shorter survival times. We found several inflammatory factors to be significantly increased in serum from mice given F nucleatum (interleukin 17F, interleukin 21, and interleukin 22, and MIP3A). We found 50 miRNAs to be significantly up-regulated and 52 miRNAs to be significantly down-regulated in CRCs incubated with F nucleatum vs PBS; levels of miR21 increased by the greatest amount (>4-fold). Inhibitors of miR21 prevented F nucleatum from inducing cell proliferation and invasion in culture. miR21a-/- mice had a later appearance of fecal blood and diarrhea after administration of azoxymethane and dextran sodium sulfate, and had longer survival times compared with control mice. The colorectum of miR21a-/- mice had fewer tumors, of smaller size, and the miR21a-/- mice survived longer than control mice. We found RASA1, which encodes an RAS GTPase, to be one of the target genes consistently down-regulated in cells that overexpressed miR21 and up-regulated in cells exposed to miR21 inhibitors. Infection of cells with F nucleatum increased expression of miR21 by activating Toll-like receptor 4 signaling to MYD88, leading to activation of the nuclear factor-κB. Levels of F nucleatum DNA and miR21 were increased in tumor tissues (and even more so in advanced tumor tissues) compared with non-tumor colon tissues from patients. Patients whose tumors had high amounts of F nucleatum DNA and miR21 had shorter survival times than patients whose tumors had lower amounts. CONCLUSIONS: We found infection of CRC cells with F nucleatum to increase their proliferation, invasive activity, and ability to form xenograft tumors in mice. Fusobacterium nucleatum activates Toll-like receptor 4 signaling to MYD88, leading to activation of the nuclear factor-κB and increased expression of miR21; this miRNA reduces levels of the RAS GTPase RASA1. Patients with both high amount of tissue F nucleatum DNA and miR21 demonstrated a higher risk for poor outcomes.


Assuntos
Neoplasias do Colo/microbiologia , DNA Bacteriano/análise , Infecções por Fusobacterium/genética , Fusobacterium nucleatum , MicroRNAs/genética , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Idoso , Animais , Azoximetano , Carcinogênese , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colite/induzido quimicamente , Neoplasias do Colo/química , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Sulfato de Dextrana , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/antagonistas & inibidores , Prognóstico , RNA Interferente Pequeno/farmacologia , Transdução de Sinais , Receptor 4 Toll-Like/genética , Regulação para Cima , Proteína p120 Ativadora de GTPase/genética
11.
Cell Physiol Biochem ; 45(2): 474-490, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29402771

RESUMO

BACKGROUND/AIMS: Recent studies have demonstrated that the manipulation of the gut microbiome represents a promising treatment for inflammatory bowel disease (IBD). We previously identified micro integral membrane protein (MIMP) as the smallest domain of surface layer protein from Lactobacillus Plantarum. However, the therapeutic relevance of MIMP in IBD remains unknown. METHODS: We initially employed a dextran sodium sulphate (DSS)-induced colitis model and evaluated the effect of MIMP on the inflammation response, intestinal barrier and gut microbiota using histological examination, Fluorescein isothiocyanate-Dextran detection and pyrosequencing analysis respectively. We then established peripheral blood mononuclear cells (PBMCs) and an epithelial CaCO-2 co-culture model to investigate the regulatory role of MIMP in inflammatory cytokines. The level changes of inflammatory cytokines were detected using Enzyme-linked immunosorbent and real-time polymerase chain reaction assay. The involved regulatory mechanisms were investigated mainly using dual luciferase reporter and chromatin immunoprecipitation assay. RESULTS: In the DSS-induced colitis model, we observed that MIMP intervention effectively improved the body weight loss, increased the colon length and decreased disease activity index. Consistently, the inflammation scores in the MIMP treatment group were significantly lower than those in the DSS treatment group. Furthermore, MIMP intervention was found to successfully neutralize DSS treatment by decreasing the expression of pro-inflammatory cytokines (IFN-γ, IL-17 and IL-23) and increasing the expression of anti-inflammatory cytokines (IL-4 and IL-10). Notably, the permeability assay demonstrated that the MIMP treatment group was remarkably lower than that in the DSS treatment group. We also showed that MIMP improved gut microbiota dysbiosis caused by DSS-induced inflammation. Additionally, in PBMCs and the CaCO-2 co-culture model, MIMP showed an obvious suppressive effect on lipopolysaccharide-induced inflammation in a time- and dose-dependent manner. Furthermore, we revealed that MIMP could modulate inflammatory cytokine expression through the toll-like receptor 4 pathway and histone acetylation. CONCLUSIONS: Our results suggested that MIMP showed a significant anti-inflammatory effect through regulating the gut barrier, microbiota and inflammatory cytokines. MIMP may have translational relevance as clinically relevant therapy for IBD patients.


Assuntos
Proteínas de Bactérias/farmacologia , Citocinas/análise , Intestinos/microbiologia , Lactobacillus plantarum/metabolismo , Proteínas de Membrana/farmacologia , Microbiota/efeitos dos fármacos , Animais , Proteínas de Bactérias/uso terapêutico , Células CACO-2 , Colite/induzido quimicamente , Colite/patologia , Colite/prevenção & controle , Citocinas/genética , Citocinas/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Humanos , Mucosa Intestinal/metabolismo , Intestinos/patologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Masculino , Proteínas de Membrana/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo
12.
Int J Cancer ; 136(3): 493-502, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24420815

RESUMO

Colorectal cancer (CRC) remains one of the most common types of cancer and leading causes of cancer death worldwide. Although the introduction of cytotoxic drugs such as oxaliplatin, irinotecan and fluorouracil has improved the treatment of advanced CRC, the individual response to chemoradiotherapy varies tremendously from one patient to another. However, recent progress in CRC molecular therapies may provide new insight into the treatment of this disease. Currently, components of the EGFR, VEGF, Wnt and NF-kB pathways are the most important targets for CRC therapy. This review chronicles the development of molecular CRC therapies over the past few decades. We also provide an update on the current progress of research concerning the molecular pathways leading to CRC and discuss the possible implications for CRC therapy.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Receptores ErbB/antagonistas & inibidores , Humanos , Terapia de Alvo Molecular , NF-kappa B/antagonistas & inibidores , NF-kappa B/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Via de Sinalização Wnt/efeitos dos fármacos
13.
Future Oncol ; 11(12): 1791-808, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075447

RESUMO

Colorectal carcinogenesis represents a sequential progression of normal colonic mucosa from adenoma to carcinoma. It has become apparent that miRNA deregulation contributes to the initiation and progression of colorectal cancer (CRC). These oncogenic or tumor-suppressive miRNAs interact with intracellular signaling networks and lead to alteration of cell proliferation, apoptosis, metastasis and even response to chemotherapeutic treatments. This article aims to review the cutting edge progress in the discovery of the role of novel mechanisms for miRNAs in the development of CRC. We will also discuss the potential use of miRNAs as biomarkers for early diagnosis and prognosis of CRC. Furthermore, with advancements in RNA delivery technology, it is anticipated that manipulation of miRNAs may offer an alternative therapy for CRC treatment.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , MicroRNAs/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/secundário , Animais , Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Prognóstico , Interferência de RNA
14.
J Biol Chem ; 288(47): 33667-33681, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24089522

RESUMO

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.


Assuntos
Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitinação , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Regulação para Baixo/genética , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Fosforilação/genética , Estabilidade Proteica , Estrutura Terciária de Proteína , Transporte Proteico/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Ubiquitina-Proteína Ligases/genética
15.
Hepatology ; 58(3): 1011-20, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23532963

RESUMO

UNLABELLED: Yes-associated protein (YAP), the downstream effecter of the Hippo-signaling pathway as well as cyclic adenosine monophosphate response element-binding protein (CREB), has been linked to hepatocarcinogenesis. However, little is known about whether and how YAP and CREB interact with each other. In this study, we found that YAP-CREB interaction is critical for liver cancer cell survival and maintenance of transformative phenotypes, both in vitro and in vivo. Moreover, both CREB and YAP proteins are highly expressed in a subset of human liver cancer samples and are closely correlated. Mechanistically, CREB promotes YAP transcriptional output through binding to -608/-439, a novel region from the YAP promoter. By contrast, YAP promotes protein stabilization of CREB through interaction with mitogen-activated protein kinase 14 (MAPK14/p38) and beta-transducin repeat containing E3 ubiquitin protein ligase (BTRC). Gain-of-function and loss-of-function studies demonstrated that phosphorylation of CREB by MAPK14/p38 at ser133 ultimately leads to its degradation. Such effects can be enhanced by BTRC through phosphorylation of MAPK14/p38 at Thr180/Tyr182. However, YAP negatively controls phosphorylation of MAPK14/p38 through inhibition of BTRC expression. CONCLUSION: There is a novel positive autoregulatory feedback loop underlying the interaction between YAP and CREB in liver cancer, suggesting that YAP and CREB form a nexus to integrate the protein kinase A, Hippo/YAP, and MAPK14/p38 pathways in cancer cells and thus may be helpful in the development of effective diagnosis and treatment strategies against liver cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinogênese/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fosfoproteínas/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Células Cultivadas , Retroalimentação Fisiológica/fisiologia , Xenoenxertos , Homeostase/fisiologia , Humanos , Técnicas In Vitro , Camundongos , Camundongos Nus , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Fosforilação/fisiologia , Fatores de Transcrição , Proteínas de Sinalização YAP , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Biochem Biophys Res Commun ; 439(2): 167-72, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23994632

RESUMO

Yes-associated protein (YAP), the downstream effector of Hippo signaling pathway as well as c-Myc has been linked to hepatocarcinogenesis. However, little is known about whether and how YAP and c-Myc interacts with each other. In this study, we find YAP-c-Myc interaction is critical for liver cancer cell both in vitro and in vivo. Moreover, both c-Myc and YAP proteins are closely correlated in human liver cancer samples. Mechanistically, YAP promotes c-Myc transcriptional output through c-Abl. By contrast, c-Myc enhances protein expression independent of transcription. Taken together, our study uncovers a novel positive auto-regulatory feedback loop underlying the interaction between YAP and c-Myc in liver cancer, suggesting YAP and c-Myc links Hippo/YAP and c-Myc pathways, and thus may be helpful in the development of effective diagnosis and treatment strategies against liver cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fígado/patologia , Fosfoproteínas/metabolismo , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Humanos , Fígado/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-abl/metabolismo , Transdução de Sinais , Fatores de Transcrição , Proteínas de Sinalização YAP
17.
Front Public Health ; 11: 1251609, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074706

RESUMO

Objective: We investigated the epidemiological surveillance of the intestinal colonization and nosocomial infection of carbapenem-resistant Enterobacteriales (CRE) isolates from inpatients, which can provide the basis for developing effective prevention. Methods: A total of 96 CRE strains were collected from 1,487 fecal samples of hospitalized children between January 2016 and June 2017, which were defined as the "CRE colonization" group. In total, 70 CRE clinical isolates were also randomly selected for the comparison analysis and defined as the "CRE infection" group. The antimicrobial susceptibility of all strains was determined by the microdilution broth method. Polymerase chain reaction (PCR) was used to analyze carbapenemase genes, plasmid typing, and integrons. Multilocus sequence typing was further used to determine clonal relatedness. Results: In the "CRE colonization" group, Klebsiella pneumoniae was mostly detected with a rate of 42.7% (41/96), followed by Escherichia coli (34.4%, 33/96) and Enterobacter cloacae (15.6%, 15/96). The ST11 KPC-2 producer, ST8 NDM-5 producer, and ST45 NDM-1 producer were commonly present in carbapenem-resistant K. pneumoniae (CRKPN), carbapenem-resistant E. coli (CRECO), and carbapenem-resistant E. cloacae (CRECL) isolates, respectively. In the "CRE infection" group, 70% (49/70) of strains were K. pneumoniae, with 21.4% E. cloacae (15/70) and 5.7% E. coli (4/70). The ST15 OXA-232 producer and ST48 NDM-5 producer were frequently observed in CRKPN isolates, while the majority of NDM-1-producing CRECL isolates were assigned as ST45. Phylogenetic analysis showed that partial CRE isolates from intestinal colonization and nosocomial infection were closely related, especially for ST11 KPC-2-producing CRKPN and ST45 NDM-1-producing CRECL. Furthermore, plasmid typing demonstrated that IncF and IncFIB were the most prevalent plasmids in KPC-2 producers, while IncX3/IncX2 and ColE were widely spread in NDM producer and OXA-232 producer, respectively. Then, class 1 integron intergrase intI1 was positive in 74.0% (71/96) of the "CRE colonization" group and 52.9% (37/70) of the "CRE infection" group. Conclusion: This study revealed that CRE strains from intestinal colonization and nosocomial infection showed a partial correlation in the prevalence of CRE, especially for ST11 KPC-2-producing CRKPN and ST45 NDM-1-producing CRECL. Therefore, before admission, long-term active screening of rectal colonization of CRE isolates should be emphasized.


Assuntos
Carbapenêmicos , Infecção Hospitalar , Criança , Humanos , Carbapenêmicos/farmacologia , Estudos Retrospectivos , Escherichia coli/genética , Antibacterianos/farmacologia , Infecção Hospitalar/epidemiologia , Prevalência , Filogenia , Klebsiella pneumoniae/genética
18.
ACS Appl Mater Interfaces ; 15(51): 59236-59245, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38096273

RESUMO

Circulating tumor cells (CTCs) are the "seeds" for malignant tumor metastasis, and they serve as an ideal target for minimally invasive tumor diagnosis. Abnormal glycolysis in tumor cells, characterized by glycometabolism disorder, has been reported as a universal phenomenon observed in various types of tumors. This provides a potential powerful tool for universal CTC capture. However, to the best of our knowledge, no metabolic glycoengineering-based CTC capture strategies have been reported. Here, we proposed a nondestructive CTC capture method based on metabolic glycoengineering and a nanotechnology-based proximity effect, allowing for highly specific, sensitive, and universal CTC capture. To achieve this goal, cells are first labeled with DNA tags through metabolic glycoengineering and then captured through a DNA tetrahedra-functionalized dual-tentacle magnetic nanodevice. Due to the difference in metabolic performance, only tumor cells are labeled with more densely packed DNA tags and captured through enhanced intermolecular interaction mediated by the proximity effect. In summary, we have constructed a versatile platform for nondestructive CTC capture, offering a novel perspective for the application of CTC liquid biopsy in tumor diagnosis and treatment.


Assuntos
Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/metabolismo , Separação Celular/métodos , Biópsia Líquida , DNA
19.
Lung Cancer ; 171: 70-81, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35930829

RESUMO

BACKGROUND & AIMS: Non-small cell lung cancer (NSCLC) accounts for about 80% of lung cancer diagnoses across the world. Despite recent appreciable improvements in treatment plans for patients with NSCLC, the prognosis for those with the cancer still remains poor. Recently, a growing number of studies have shown that N-myristoyltransferases (NMTs) may be critical in carcinogenesis, however, the functional and clinical significance of this pathway in NSCLC remains unclear and requires further research. METHODS: Initially, we evaluated the expression levels of NMT1 or NMT2 in a clinical cohort comprising of 303 paired primary NSCLC tissues and matched normal mucosae by using ELISA. We subsequently performed a tissue microarray analysis (TMA) to confirm its expression pattern in an independent validation cohort (n = 78). Then, we used a publicly available KM plotter database (n = 1921) to evaluate the prognostic impact of NMT1 and NMT2 in NSCLC. Lastly, a series of in-vitro molecular/cellular and animal experiments were performed for mechanistic understanding of the role of N-myristoyltransferases in NSCLC. RESULTS: Our ELISA data revealed that the expression level of NMT1 and NMT2 was down-regulated in tumor tissues (n = 303, P < 0.0001), which was confirmed in an independent validation cohort by TMA (n = 78, P = 0.014 for NMT1 and P < 0.0001 for NMT2). On the other hand, patients with low expression of NMT1 or NMT2 had shorter overall survival (P = 0.013, HR = 0.85 for NMT1; P = 0.00059, HR = 0.8, for NMT2). Mechanistically, we revealed that the interaction and co-localization of NMT1 and NMT2 in NSCLC, and N-terminus of NMT1 and NMT2 was observed to be crucial for their interaction as well as for their catalytic activity. Moreover, we found that NMT1 can significantly promote the expression of NMT2 by enhancing its stability. We corroborated these findings by performing functional assays in which the knockout of NMT1 and NMT2 resulted in enhanced cell proliferation, migration and invasion as well as increased tumorxenograftgrowth. In addition, we identified miR-182 as a novel regulator of both NMT1 and NMT2. More specifically, the overexpression or inhibition of miR-182 modulated globe N-myristoylation level, contributed to phenotypic alterations in NSCLS cells. CONCLUSIONS: NMT1 and NMT2 can act as potential tumor suppressors in NSCLC, and the inhibition of miR-182 expression or therapeutic NMTs replenishment may be a promising treatment option for patients with NSCLC.


Assuntos
Aciltransferases , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Aciltransferases/genética , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Prognóstico
20.
Biochem Biophys Res Commun ; 405(2): 278-84, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21219856

RESUMO

Tumor protein p53-induced nuclear protein 1 (TP53INP1) is a well known stress-induced protein that plays a role in both cell cycle arrest and p53-mediated apoptosis. Loss of TP53INP1 expression has been reported in human melanoma, breast carcinoma, and gastric cancer. However, TP53INP1 expression and its regulatory mechanism in esophageal squamous cell carcinoma (ESCC) remain unclear. Our findings are in agreement with previous reports in that the expression of TP53INP1 was downregulated in 28% (10/36 cases) of ESCC lesions, and this was accompanied by significant promoter methylation. Overexpression of TP53INP1 induced G1 cell cycle arrest and increased apoptosis in ESCC cell lines (EC-1, EC-109, EC-9706). Furthermore, our study showed that the oncoprotein c-Myc bound to the core promoter of TP53INP1 and recruited DNA methyltransferase 3A to methylate the local promoter region, leading to the inhibition of TP53INP1 expression. Our findings revealed that TP53INP1 is a tumor suppressor in ESCC and that c-Myc-mediated DNA methylation-associated silencing of TP53INP1 contributed to the pathogenesis of human ESCC.


Assuntos
Carcinoma de Células Escamosas/genética , Proteínas de Transporte/genética , Metilação de DNA , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Proteínas de Choque Térmico/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Regulação para Baixo , Humanos , Regiões Promotoras Genéticas
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