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1.
EMBO J ; 43(1): 61-86, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177310

RESUMO

Accumulation of DNA damage in the lung induces cellular senescence and promotes age-related diseases such as idiopathic pulmonary fibrosis (IPF). Hence, understanding the mechanistic regulation of DNA damage repair is important for anti-aging therapies and disease control. Here, we identified an m6A-independent role of the RNA-binding protein YTHDC1 in counteracting stress-induced pulmonary senescence and fibrosis. YTHDC1 is primarily expressed in pulmonary alveolar epithelial type 2 (AECII) cells and its AECII expression is significantly decreased in AECIIs during fibrosis. Exogenous overexpression of YTHDC1 alleviates pulmonary senescence and fibrosis independent of its m6A-binding ability, while YTHDC1 deletion enhances disease progression in mice. Mechanistically, YTHDC1 promotes the interaction between TopBP1 and MRE11, thereby activating ATR and facilitating DNA damage repair. These findings reveal a noncanonical function of YTHDC1 in delaying cellular senescence, and suggest that enhancing YTHDC1 expression in the lung could be an effective treatment strategy for pulmonary fibrosis.


Assuntos
Senescência Celular , Fibrose Pulmonar Idiopática , Proteínas do Tecido Nervoso , Fatores de Processamento de RNA , Animais , Camundongos , Envelhecimento/genética , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Fatores de Processamento de RNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo
2.
Drug Resist Updat ; 73: 101052, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38262246

RESUMO

AIMS: This investigation aims to elucidate the mechanism underlying sorafenib-induced ferroptosis in hepatocellular carcinoma (HCC). METHODS: The role of dual specificity phosphatase 4 (DUSP4) in sorafenib-treated HCC was investigated using comprehensive assessments both in vitro and in vivo, including Western blotting, qRT-PCR, cell viability assay, lipid reactive oxygen species (ROS) assay, immunohistochemistry, and xenograft tumor mouse model. Additionally, label-free quantitative proteomics was employed to identify potential proteins associated with DUSP4. RESULTS: Our study revealed that suppression of DUSP4 expression heightens the susceptibility of HCC cells to ferroptosis inducers, specifically sorafenib and erastin, in both in vitro and in vivo settings. Furthermore, we identified DUSP4-mediated regulation of key ferroptosis-related markers, such as ferritin light chain (FTL) and ferritin heavy chain 1 (FTH1). Notably, label-free quantitative proteomics unveiled the phosphorylation of threonine residue T148 on YTH Domain Containing 1 (YTHDC1) by DUSP4. Further investigations unraveled that YTHDC1, functioning as an mRNA nuclear export regulator, is a direct target of DUSP4, orchestrating the subcellular localization of FTL and FTH1 mRNAs. Significantly, our study highlights a strong correlation between elevated DUSP4 expression and sorafenib resistance in HCC. CONCLUSIONS: Our findings introduce DUSP4 as a negative regulator of sorafenib-induced ferroptosis. This discovery opens new avenues for the development of ferroptosis-based therapeutic strategies tailored for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Monoéster Fosfórico Hidrolases/uso terapêutico , Ferroptose/genética , Linhagem Celular Tumoral
3.
Mol Ther ; 30(8): 2828-2843, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35524408

RESUMO

Translational reprogramming is part of the unfolded protein response (UPR) during endoplasmic reticulum (ER) stress, which acts to the advantage of cancer growth and development in different stress conditions, but the mechanism of ER stress-related translational reprogramming in colorectal carcinoma (CRC) progression remains unclear. Here, we identified that Krüppel-like factor 16 (KLF16) can promote CRC progression and stress tolerance through translational reprogramming. The expression of KLF16 was upregulated in CRC tissues and associated with poor prognosis for CRC patients. We found that ER stress inducers can recruit KLF16 to the nucleolus and increase its interaction with two essential proteins for nucleolar homeostasis: nucleophosmin1 (NPM1) and fibrillarin (FBL). Moreover, knockdown of KLF16 can dysregulate nucleolar homeostasis in CRC cells. Translation-reporter system and polysome profiling assays further showed that KLF16 can effectively promote cap-independent translation of ATF4, which can enhance ER-phagy and the proliferation of CRC cells. Overall, our study unveils a previously unrecognized role for KLF16 as an ER stress regulator through mediating translational reprogramming to enhance the stress tolerance of CRC cells and provides a potential therapeutic vulnerability.


Assuntos
Neoplasias Colorretais , Fatores de Transcrição Kruppel-Like , Resposta a Proteínas não Dobradas , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Estresse do Retículo Endoplasmático/genética , Homeostase , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo
4.
BMC Med Imaging ; 23(1): 210, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087207

RESUMO

BACKGROUND: Mutated KRAS may indicate an invasive nature and predict prognosis in locally advanced rectal cancer (LARC). We aimed to establish a radiomic model using pretreatment T2W MRIs to predict KRAS status and explore the association between the KRAS status or model predictions and lung metastasis. METHODS: In this retrospective multicentre study, LARC patients from two institutions between January 2012 and January 2019 were randomly divided into training and testing cohorts. Least absolute shrinkage and selection operator (LASSO) regression and the support vector machine (SVM) classifier were utilized to select significant radiomic features and establish a prediction model, which was validated by radiomic score distribution and decision curve analysis. The association between the model stratification and lung metastasis was investigated by Cox regression and Kaplan‒Meier survival analysis; the results were compared by the log-rank test. RESULTS: Overall, 103 patients were enrolled (73 and 30 in the training and testing cohorts, respectively). The median follow-up was 38.1 months (interquartile range: 26.9, 49.4). The radiomic model had an area under the curve (AUC) of 0.983 in the training cohort and 0.814 in the testing cohort. Using a cut-off of 0.679 defined by the receiver operating characteristic (ROC) curve, patients with a high radiomic score (RS) had a higher risk for lung metastasis (HR 3.565, 95% CI 1.337, 9.505, p = 0.011), showing similar predictive performances for the mutant and wild-type KRAS groups (HR 3.225, 95% CI 1.249, 8.323, p = 0.016, IDI: 1.08%, p = 0.687; NRI 2.23%, p = 0.766). CONCLUSIONS: We established and validated a radiomic model for predicting KRAS status in LARC. Patients with high RS experienced more lung metastases. The model could noninvasively detect KRAS status and may help individualize clinical decision-making.


Assuntos
Neoplasias Pulmonares , Neoplasias Retais , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/genética , Neoplasias Retais/terapia
5.
Phytother Res ; 37(9): 4210-4223, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37253360

RESUMO

Type 2 diabetes mellitus (T2DM) and its complications have become a serious global health epidemic. Cardiovascular complications have considered as a major cause of high mortality in diabetic patients. Fucoidans from brown algae have diverse medicinal activities, however, few studies reported pharmacological activity of Sargassum. pallidum fucoidan (Sp-Fuc). Therefore, the aim of this study was to investigate the effects of Sp-Fuc on diabetic symptoms and cardiac injury in spontaneous diabetic db/db mice. SP-Fuc at 200 mg/(kg/d) was administered intragastrically to db/db mice for 8 weeks, the effects on hyperlipidemia, hyperglycemia, insulin resistance, and cardiac damage, as well as oxidative stress, inflammation, Nrf2/ARE, and NF-κB signaling pathways, were investigated. Our data demonstrated that Sp-Fuc significantly (p < 0.05) decreased body weights, hyperlipidemia, and hyperglycemia in db/db mice, along with improved insulin sensitivity. Additionally, Sp-Fuc significantly (p < 0.05) alleviated cardiac dysfunction and pathological morphology of cardiac tissue. Sp-Fuc also significantly (p < 0.05) decreased lipid peroxidation, increased antioxidant function, as well as reduced cardiac inflammation, possibly through Nrf2/ARE and NF-κB signaling. Sp-Fuc can ameliorate the metabolism disorders of glucose and lipid in diabetic mice by activating Nrf2/ARE antioxidant signaling, simultaneously reducing cardiac redox imbalance and inflammatory damage. The present findings provide a perspective on the therapy strategy for T2DM and its complications.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Sargassum , Camundongos , Animais , Antioxidantes/farmacologia , NF-kappa B/metabolismo , Fígado , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Experimental/complicações , Fator 2 Relacionado a NF-E2/metabolismo , Globo Pálido/metabolismo , Estresse Oxidativo , Inflamação/tratamento farmacológico , Hiperglicemia/metabolismo
6.
Mol Cancer ; 21(1): 93, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366894

RESUMO

BACKGROUND: Circular RNAs (circRNAs) regulate various biological activities and have been shown to play crucial roles in hepatocellular carcinoma (HCC) progression. However, only a few coding circRNAs have been identified in cancers, and their roles in HCC remain elusive. This study aimed to identify coding circRNAs and explore their function in HCC. METHODS: CircMAP3K4 was selected from the CIRCpedia database. We performed a series of experiments to determine the characteristics and coding capacity of circMAP3K4. We then used in vivo and in vitro assays to investigate the biological function and mechanism of circMAP3K4 and its protein product, circMAP3K4-455aa, in HCC. RESULTS: We found circMAP3K4 to be an upregulated circRNA with coding potential in HCC. IGF2BP1 recognized the circMAP3K4 N6-methyladenosine modification and promoted its translation into circMAP3K4-455aa. Functionally, circMAP3K4-455aa prevented cisplatin-induced apoptosis in HCC cells by interacting with AIF, thus protecting AIF from cleavage and decreasing its nuclear distribution. Moreover, circMAP3K4-455aa was degraded through the ubiquitin-proteasome E3 ligase MIB1 pathway. Clinically, a high level of circMAP3K4 is an independent prognostic factor for adverse overall survival and adverse disease-free survival of HCC patients. CONCLUSIONS: CircMAP3K4 is a highly expressed circRNA in HCC. Driven by m6A modification, circMAP3K4 encoded circMAP3K4-455aa, protected HCC cells from cisplatin exposure, and predicted worse prognosis of HCC patients. Targeting circMAP3K4-455aa may provide a new therapeutic strategy for HCC patients, especially for those with chemoresistance. CircMAP3K4 is a highly expressed circRNA in HCC. Driven by m6A modification, IGF2BP1 facilitates circMAP3K4 peptide translation, then the circMAP3K4 peptide inhibits AIF cleavage and nuclear distribution, preventing HCC cells from cell death under stress and promoting HCC progression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Adenosina/análogos & derivados , Apoptose , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Peptídeos
7.
Cancer Sci ; 113(6): 2008-2021, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35348274

RESUMO

DNA high methylation is one of driving force for colorectal carcinoma (CRC) pathogenesis. Transcription factors (TFs) can determine cell fate and play fundamental roles in multistep process of tumorigenesis. Dysregulation of DNA methylation of TFs should be vital for the progression of CRC. Here, we demonstrated that TBX20, a T-box TF family protein, was downregulated with hypermethylation of promoter in early-stage CRC tissues and correlated with a poor prognosis for CRC patients. Moreover, we identified PDZRN3 as the E3 ubiquitin ligase of TBX20 protein, which mediated the ubiquitination and degradation of TBX20. Furthermore, we revealed that TBX20 suppressed cell proliferation and tumor growth through impairing non-homologous DNA end joining (NHEJ)-mediated double-stranded break repair by binding the middle domain of both Ku70 and Ku80 and therefore inhibiting their recruitment on chromatin in CRC cells. Altogether, our results reveal the tumor-suppressive role of TBX20 by inhibiting NHEJ-mediated DNA repair in CRC cells, and provide a potential biomarker for predicting the prognosis of patients with early-stage CRC and a therapeutic target for combination therapy.


Assuntos
Neoplasias Colorretais , Quebras de DNA de Cadeia Dupla , Proteínas com Domínio T , Proteínas Mutadas de Ataxia Telangiectasia , Carcinogênese , Neoplasias Colorretais/genética , DNA , Reparo do DNA por Junção de Extremidades/genética , Reparo do DNA/genética , Humanos , Proteínas com Domínio T/genética
8.
Br J Cancer ; 127(2): 249-257, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35368044

RESUMO

BACKGROUND: To analyse the performance of multicentre pre-treatment MRI-based radiomics (MBR) signatures combined with clinical baseline characteristics and neoadjuvant treatment modalities to predict complete response to neoadjuvant (chemo)radiotherapy in locally advanced rectal cancer (LARC). METHODS: Baseline MRI and clinical characteristics with neoadjuvant treatment modalities at four centres were collected. Decision tree, support vector machine and five-fold cross-validation were applied for two non-imaging and three radiomics-based models' development and validation. RESULTS: We finally included 674 patients. Pre-treatment CEA, T stage, and histologic grade were selected to generate two non-imaging models: C model (clinical baseline characteristics alone) and CT model (clinical baseline characteristics combining neoadjuvant treatment modalities). The prediction performance of both non-imaging models were poor. The MBR signatures comprising 30 selected radiomics features, the MBR signatures combining clinical baseline characteristics (CMBR), and the CMBR incorporating neoadjuvant treatment modalities (CTMBR) all showed good discrimination with mean AUCs of 0.7835, 0.7871 and 0.7916 in validation sets, respectively. The three radiomics-based models had insignificant discrimination in performance. CONCLUSIONS: The performance of the radiomics-based models were superior to the non-imaging models. MBR signatures seemed to reflect LARC's true nature more accurately than clinical parameters and helped identify patients who can undergo organ preservation strategies.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Imageamento por Ressonância Magnética/métodos , Terapia Neoadjuvante/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Reto/patologia , Estudos Retrospectivos
9.
Mol Cancer ; 20(1): 103, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34412652

RESUMO

BACKGROUND: Constitutive activation of nuclear factor-κB (NF-κB) signaling plays a key role in the development and progression of colorectal carcinoma (CRC). However, the underlying mechanisms of excessive activation of NF-κB signaling remain largely unknown. METHODS: We used high throughput RNA sequencing to identify differentially expressed circular RNAs (circRNAs) between normal human intestinal epithelial cell lines and CRC cell lines. The identification of protein encoded by circPLCE1 was performed using LC-MS. The function of novel protein was validated in vitro and in vivo by gain or loss of function assays. Mechanistic results were concluded by immunoprecipitation analyses. RESULTS: A novel protein circPLCE1-411 encoded by circular RNA circPLCE1 was identified as a crucial player in the NF-κB activation of CRC. Mechanistically, circPLCE1-411 promoted the ubiquitin-dependent degradation of the critical NF-κB regulator RPS3 via directly binding the HSP90α/RPS3 complex to facilitate the dissociation of RPS3 from the complex, thereby reducing NF-κB nuclear translocation in CRC cells. Functionally, circPLCE1 inhibited tumor proliferation and metastasis in CRC cells, as well as patient-derived xenograft and orthotopic xenograft tumor models. Clinically, circPLCE1 was downregulated in CRC tissues and correlated with advanced clinical stages and poor survival. CONCLUSIONS: circPLCE1 presents an epigenetic mechanism which disrupts NF-κB nuclear translocation and serves as a novel and promising therapeutic target and prognostic marker.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , NF-kappa B/metabolismo , Fosfoinositídeo Fosfolipase C/genética , RNA Circular , Proteínas Ribossômicas/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Cromatografia Líquida , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Modelos Biológicos , Proteólise , Proteômica/métodos , Transdução de Sinais , Espectrometria de Massas em Tandem , Ubiquitina/metabolismo , Ubiquitinação
10.
Mol Ther ; 28(3): 914-928, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-31951832

RESUMO

Increasing studies indicated that circular RNAs (circRNAs) play important roles in cancer progression. However, the roles of circRNAs in colorectal cancer (CRC) remain largely unknown. In this study, we determined the circRNA expression profile by next-generation RNA sequencing from eight CRC and paired non-cancerous matched tissues. circCAMSAP1 (originating from exon 2 to exon 3 of the CAMSAP1 gene, hsa_circ_0001900) was significantly upregulated in CRC tissues. Increased circCAMSAP1 expression was significantly correlated with advanced tumor/node/metastasis (TNM) stage and shortened overall survival. An elevation of circCAMSAP1 expression was detected via droplet digital PCR in the serum of CRC patients prior to surgery. Functionally, circCAMSAP1 promoted the malignant behavior of CRC. Mechanism study of upstream biogenesis of circCAMSAP1 indicated that circCAMSAP1 cyclization in CRC was mediated by splicing factor epithelial-splicing regulatory protein 1. Moreover, circCAMSAP1 acted as a sponge for miR-328-5p and abrogated its suppression on transcription factor E2F1. Taken together, our data indicated an essential role of the circCAMSAP1/miR-328-5p/E2F1 axis in the progression of CRC, which implied that circCAMSAP1 could serve as a diagnostic and prognostic biomarker as well as a potential therapeutic target for CRC.


Assuntos
Neoplasias Colorretais/genética , Fator de Transcrição E2F1/genética , MicroRNAs/genética , Proteínas Associadas aos Microtúbulos/genética , RNA Circular/genética , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Modelos Biológicos , Prognóstico , Interferência de RNA , Splicing de RNA
11.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668146

RESUMO

Independent component analysis (ICA) is one of the most effective approaches in extracting independent signals from a global navigation satellite system (GNSS) regional station network. However, ICA requires the involved time series to be complete, thereby the missing data of incomplete time series should be interpolated beforehand. In this contribution, a modified ICA is proposed, by which the missing data are first recovered based on the reversible property between the original time series and decomposed principal components, then the complete time series are further processed with FastICA. To evaluate the performance of the modified ICA for extracting independent components, 24 regional GNSS network stations located in North China from 2011 to 2019 were selected. After the trend, annual and semiannual terms were removed from the GNSS time series, the first two independent components captured 17.42, 18.44 and 17.38% of the total energy for the North, East and Up coordinate components, more than those derived by the iterative ICA that accounted for 16.21%, 17.72% and 16.93%, respectively. Therefore, modified ICA can extract more independent signals than iterative ICA. Subsequently, selecting the 7 stations with less missing data from the network, we repeatedly process the time series after randomly deleting parts of the data and compute the root mean square error (RMSE) from the differences of reconstructed signals before and after deleting data. All RMSEs of modified ICA are smaller than those of iterative ICA, indicating that modified ICA can extract more exact signals than iterative ICA.

12.
Pak J Pharm Sci ; 34(6 Spec): 2479-2485, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-35039263

RESUMO

This study aims to investigate the curative effect of Kangfuyan capsule in the treatment of damp-heat and blood stasis type of pelvic inflammatory disease (PID), and its influence on serum inflammatory factors IL-6, CRP and TNF-α. A total of 83 patients with PID were randomly divided into two groups: Western medicine group (control group, n=41) received oral antibiotics (azithromycin + metronidazole) alone and the traditional Chinese medicine combined with Western medicine group (experimental group, n=42) received Kangfuyan capsule based on Western medicine therapy. Clinical efficacy between these two groups and the influence of drugs in serum inflammatory factors (IL-6, CRP and TNF-α) were compared. The total effective rate was 78.05% in the control group and 97.62% in the experimental group and difference between these two groups was statistically significant (P<0.01). The symptoms and signs in the two groups significantly improved after treatment (P<0.05) and improvement rate was significantly better in the experimental group than in the control group (P<0.05). After treatment, serum inflammatory factor levels in the two groups were significantly lower than levels before treatment (P<0.05) and improvement rate was significantly better in the experimental group than in the control group (P<0.05). Kangfuyan capsule combined with antibiotics can effectively relieve the symptoms and signs of patients, improve the efficiency of treatment, provide high safety, and does not increase adverse reactions. The possible mechanism may be that this therapy suppresses chronic PID by reducing serum inflammatory factor (IL-6, CRP and TNF-α) levels.


Assuntos
Antibacterianos , Azitromicina , Medicamentos de Ervas Chinesas , Metronidazol , Doença Inflamatória Pélvica , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Azitromicina/efeitos adversos , Azitromicina/uso terapêutico , Biomarcadores/sangue , China , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Mediadores da Inflamação/sangue , Metronidazol/efeitos adversos , Metronidazol/uso terapêutico , Doença Inflamatória Pélvica/sangue , Doença Inflamatória Pélvica/diagnóstico , Doença Inflamatória Pélvica/tratamento farmacológico , Fatores de Tempo , Resultado do Tratamento
13.
Mol Cancer ; 19(1): 60, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188489

RESUMO

BACKGROUND: Metastasis causes the vast majority of colorectal carcinoma (CRC)-related deaths. However, little is known about the specific traits and underlying mechanisms of metastasis-initiating cells in primary CRC. And whether or not circular RNAs (circRNAs) take part in this particular event remain not adequately stated yet. METHODS: A screening method based on Transwell assay was first applied to build CRC subgroups with different metastatic potential. High throughput RNA sequencing was used to find out novel metastatic drivers in CRC metastasis-initiating step. A series of in vitro and in vivo assays were further applied to elucidate the functions and underlying molecular mechanisms of circRNAs in CRC metastasis. RESULTS: A circRNA consisting of exon 8-11 of LONP2, termed as circLONP2, was upregulated in metastasis-initiating CRC subgroups. Aberrant higher expression of circLONP2 was observed in primary CRC tissues with established metastasis, and along the invasive margin in metastatic site. High expression of circLONP2 predicted unfavorable overall survival. Functional studies revealed that circLONP2 could enhance the invasiveness of CRC cells in vitro, and targeting circLONP2 through anti-sense oligonucleotide (ASO) dramatically reduced the penetrance of metastasis to foreign organs in vivo. Mechanically, circLONP2 directly interacted with and promoted the processing of primary microRNA-17 (pri-miR-17), through recruiting DiGeorge syndrome critical region gene 8 (DGCR8) and Drosha complex in DDX1-dependent manner. Meanwhile, upregulated mature miR-17-5p could be assembled into exosomes and internalized by neighboring cells to enhance their aggressiveness. CONCLUSIONS: Our data indicate that circLONP2 acts as key metastasis-initiating molecule during CRC progression through modulating the intracellular maturation and intercellular transfer of miR-17, resulting in dissemination of metastasis-initiating ability in primary site and acceleration of metastasis formation in foreign organs. circLONP2 could serve as an effective prognostic predictor and/or novel anti-metastasis therapeutic target in CRC treatment.


Assuntos
Neoplasias Colorretais/patologia , RNA Helicases DEAD-box/metabolismo , Exossomos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/secundário , MicroRNAs/genética , RNA Circular/genética , Proteases Dependentes de ATP/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , RNA Helicases DEAD-box/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Mol Pharm ; 17(5): 1546-1557, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32267710

RESUMO

Antibody-coupled photosensitive molecules can achieve an ideal tumor-specific photodynamic therapy (PDT) and show strong clinical application potential. However, some inherent disadvantages, such as long circulation half-life, poor permeation into solid tumors, and difficulty in obtaining uniform coupling products, present potential problems to clinical applications. In this study, we propose a novel design of targeting photosensitizers, based on a very small targeting protein (an affibody molecule) coupled with photosensitive compounds, to address these problems. In the synthesis, photosensitive pyropheophorbide-a (Pyro) is modified with a PEG linker (molecular weight of 727 Da) and then site specifically coupled to the anti-HER2 ZHER2:2891 affibody protein to provide a homogeneous protein-coupled photosensitizer via a convenient process. In vitro and in vivo experiments show that this molecule has an ideal selectivity for binding and photocytotoxicity against HER2-positive cells (more than 50-fold selectivity between HER2-high expression and HER2-low expression cells) and highly specific tumor accumulation; at a relatively low dose, it effectively eliminated HER2-high expression NCI-N87 tumors in a mouse model. It is worth noting that Pyro only has a moderate photodynamic activity; however, the affibody-coupled Pyro molecule (Pyro-Linker-ZHER2) still shows excellent tumor therapeutic function. The more ideal tumor permeability of small ligands may be helpful to enhance the drug concentration in the tumor site and the ability to penetrate deeply inside the tumor. Coupling photosensitive compounds with affibody proteins may provide a new way for targeting PDT of tumors.


Assuntos
Anticorpos/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Receptor ErbB-2/imunologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo , Receptor ErbB-2/análise , Receptor ErbB-2/metabolismo
15.
Stem Cells ; 36(2): 180-191, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29119708

RESUMO

Cancer stem cells (CSCs)/cancer-initiating cells (CICs) are suggested responsible for driving cancer resistance to conventional therapies and for cancer recurrence and/or metastasis. CD133 is served as a key biomarker to identify and characterize this subpopulation of cells in hepatocellular carcinoma (HCC). Our previous study indicated that overexpression of eukaryotic initiation factor 5A2 (EIF5A2) promotes HCC cell metastasis and angiogenesis. In this study, we demonstrated that EIF5A2 might play a crucial role in CSCs regulation and investigated its potential molecular mechanisms. Using quantitative real-time polymerase chain reaction assay, we observed that the expression of EIF5A2 positively correlated with CD133 levels in a cohort of cancerous and noncancerous liver tissues and cells. Next, HCC cells with high expression of EIF5A2 have a strong capacity to form undifferentiated tumor spheres in vitro and show elevated levels of stem cell-related genes, leading to an increased ability to develop tumors when subcutaneously injected into nude mice. Furthermore, differential microRNA expression was profiling between two EIF5A2-depleted HCC cell lines and their control one identified a decreased expression of miR-29b in EIF5A2-depleted cell lines. Further functional studies illustrated that downregulated miR-29b level is responsible for EIF5A2-maintained HCC cell stemness either in vitro or in vivo. Moreover, enforced expression of EIF5A2 in HCC cells largely enhanced the binding of c-Myc on the promoter of miR-29b and downregulation of miR-29b by EIF5A2 was dependent on c-Myc. Our findings, collectively, reveal that EIF5A2 contributes to the maintenance of CD133+ HCC cells via the c-Myc/miR-29b axis. Stem Cells 2018;36:180-191.


Assuntos
Antígeno AC133/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas de Ligação a RNA/metabolismo , Antígeno AC133/genética , Animais , Western Blotting , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos SCID , MicroRNAs/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Fatores de Iniciação de Peptídeos/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de Xenoenxerto , Fator de Iniciação de Tradução Eucariótico 5A
16.
Int J Gynecol Cancer ; 29(8): 1280-1284, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31570543

RESUMO

INTRODUCTION: The solute carrier family 12 member 5 (SLC12A5) gene is playing a putative oncogenic role in colorectal carcinoma. However, the status of SLC12A5 amplification and expression in ovarian carcinoma and its potential clinical and/or prognostic significance has not yet been investigated. METHODS: In the present study, semi-quantitative staining and fluorescence in situ hybridization were used to investigate SLC12A5 protein expression and gene amplification levels. Samples were obtained from archival, formalin-fixed, paraffin-embedded pathological specimens consisting of 30 normal ovaries, 30 ovarian cystadenomas, 30 borderline ovarian tumors, and 147 invasive ovarian carcinomas. SLC12A5 immunohistochemical staining results, pathological parameters, and patient prognosis were then evaluated using various statistical models. Patient survival rate was also assessed using receiver-operator curve analysis. RESULTS: Our results revealed no SLC12A5 protein overexpression in normal ovaries. However, 7% of cystadenomas had SLC12A5 protein overexpression along with 17% of borderline tumors and 37% of ovarian carcinomas (P<0.01). Amplification of SLC12A5 was detected in 10.3% of ovarian carcinomas. Further correlational analyses showed that SLC12A5 protein overexpression in ovarian carcinomas was significantly associated with ascending histological grade, pT/pN/pM status, as well as FIGO stage (P<0.05). A subsequent univariate survival analysis of our ovarian carcinoma cohorts resulted in a significant association between SLC12A5 protein overexpression and decreased patient survival (44.3 and 85.9 months for high and low SLC12A5 protein expression, respectively; P<0.001). Importantly, additional multivariate analysis revealed that SLC12A5 protein expression was a significant, independent prognostic factor for overall survival in ovarian carcinoma patients (P=0.003). CONCLUSIONS: Collectively, these findings support the conclusion that SLC12A5 protein overexpression could indicate an invasive and/or aggressive phenotype of ovarian carcinoma. Future work will need to investigate whether SLC12A5 protein can serve as an independent prognostic molecular marker in patients with ovarian carcinoma.


Assuntos
Carcinoma Epitelial do Ovário/metabolismo , Neoplasias Ovarianas/metabolismo , Simportadores/biossíntese , Carcinoma Epitelial do Ovário/patologia , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Ovarianas/patologia , Taxa de Sobrevida , Análise Serial de Tecidos
17.
Mol Pharm ; 15(4): 1505-1514, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29502410

RESUMO

Pyropheophorbide-a (Pyro) is a highly promising photosensitizer for tumor photodynamic therapy (PDT), although its very limited tumor-accumulation ability seriously restricts its clinical applications. A higher accumulation of photosensitizers is very important for the treatment of deeply seated and larger tumors. The conjugation of Pyro with tumor-homing peptide ligands could be a very useful strategy to optimize the physical properties of Pyro. Herein, we reported our studies on the conjugation of Pyro with a cyclic cRGDfK (cRGD) peptide, an integrin binding sequence, to develop highly tumor-specific photosensitizers for PDT application. To further reduce the nonspecific uptake and, thus, reduce the background distribution of the conjugates in normal tissues, we opted to add a highly hydrophilic polyethylene glycol (PEG) chain and an extra strongly hydrophilic carboxylic acid group as the linker to avoid the direct connection of the strongly hydrophobic Pyro macrocycle and cRGD ligand. We reported here the synthesis and characterization of these conjugates, and the influence of the hydrophilic modification on the biological function of the conjugates was carefully studied. The tumor-accumulation ability and photodynamic-induced cell-killing ability of these conjugates were evaluated through both in vitro cell-based experiment and in vivo distribution and tumor therapy experiments with tumor-bearing mice. Thus, the synthesized conjugate significantly improved the tumor enrichment and tumor selectivity of Pyro, as well as abolished the xenograft tumors in the murine model through a one-time PDT treatment.


Assuntos
Clorofila/análogos & derivados , Peptídeos Cíclicos/química , Fármacos Fotossensibilizantes/química , Animais , Linhagem Celular Tumoral , Clorofila/química , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fotoquimioterapia/métodos , Polietilenoglicóis/química , Distribuição Tecidual
18.
Carcinogenesis ; 37(6): 557-566, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27207647

RESUMO

Trimethylation of lysine 27 on histone H3 (H3K27ME3) is a transcription-suppressive histone mark mediated by enhancer of zeste homolog 2 (EZH2). We have previously suggested that EZH2-mediated H3K27ME3 plays a critical oncogenic role in human hepatocellular carcinoma (HCC) aggressiveness. However, the direct downstream targets of EZH2-H3K27ME3 and the molecular mechanisms by which regulates HCC pathogenesis remain unclear. In this study, we used chromatin immunoprecipitation together with high-throughput sequencing (ChIP-seq) and gene expression profiling by microarray analysis to assess genome-wide chromatin occupancy of H3K27ME3 in HCC cells. We identified that claudin14 (CLDN14) is a potentially direct target for EZH2-mediated H3K27ME3 in HCC. In a large cohort of clinical HCC tissues, we found that low expression of CLDN14 was significantly associated with advanced tumor stage and determined to be an independent predictor of shortened survival of HCC patients. Next, functional experiment demonstrated that depletion of CLDN14 substantially restored EZH2-silenced HCC cells motility and invasive capacities and supported cell epithelial-mesenchymal transition (EMT). Furthermore, downregulation of CLDN14 dramatically re-enhanced the wnt/ß-catenin signaling activity in EZH2-silenced HCC cells by increasing the levels of active ß-catenin and promoting the nuclear localization of ß-catenin. These results, collectively, uncover that CLDN14 is a novel direct target of EZH2-mediated H3K27ME3, and provide an explanation for the aggressive nature of HCC with downregulation of CLDN14 and the underling mechanism that links the tumor suppressor CLDN14 to the wnt/ß-catenin signaling pathway.


Assuntos
Carcinoma Hepatocelular/genética , Claudinas/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias Hepáticas/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Claudinas/metabolismo , Intervalo Livre de Doença , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Metilação , Prognóstico , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
20.
BMC Cancer ; 14: 583, 2014 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-25109220

RESUMO

BACKGROUND: Hemostatic alterations occur during the development of cancer. Plasma D-dimer is a hypercoagulability and fibrinolytic system marker that is increased in patients with various solid tumours. The aim of this study was to evaluate the hemostatic status of nasopharyngeal carcinoma (NPC) patients by assessing plasma D-dimer levels to investigate its value as a prognostic marker. METHODS: We retrospectively analysed 717 patients with nasopharyngeal carcinoma, and we applied Cox regression and log-rank tests to assess the association of D-dimer levels with disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival (OS). D-dimer levels were measured using a quantitative D-dimer latex agglutination assay. RESULTS: Using the 3rd quartile values (0.8 µg/L) as the optimal cut-offs, we found that patients with high D-dimer levels have a shorter 3-year DFS, (79%, 95%CI (73.1-84.9)) vs. (69%, 95%CI (59.2-78.8)), DMFS (87%, 95%CI (83.1-90.9)) vs. (77%, 95%CI (69.2-84.8)), and overall survival (82%, 95%CI (76.1-87.9)) vs. (76%, 95%CI (66.2-85.8)). Multivariate analysis revealed that pre-treatment D-dimer levels and EBV DNA were significant independent factors for DFS, DMFS, and OS in NPC patients. Subgroup analyses indicated that the plasma D-dimer levels could effectively stratify patient prognosis for early cancer, advanced stage cancer, and patients with EBV DNA ≥4000 copies/ml. CONCLUSIONS: High D-dimer levels were associated with poor disease-free survival, distant metastasis-free survival, overall survival, and increased risk of mortality in NPC patients. Prospective trials are required to assess the prognostic value of D-dimer levels.


Assuntos
Quimiorradioterapia , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/terapia , Adulto , Idoso , Carcinoma , DNA Viral/sangue , Feminino , Herpesvirus Humano 4/genética , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/mortalidade , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
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