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1.
BMC Cancer ; 24(1): 525, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664644

RESUMO

BACKGROUND: Regorafenib, a multi-targeted kinase inhibitor, has been used in the treatment of Hepatocellular carcinoma (HCC). The purpose of this study is to investigate the mechanism of Regorafenib in HCC. METHODS: Regorafenib's impact on the sensitivity of HCC cells was assessed using CCK8. Differential gene expression analysis was performed by conducting mRNA sequencing after treatment with Regorafenib. The m6A methylation status of CHOP and differential expression of m6A methylation-related proteins were assessed by RIP and Western Blot. To explore the molecular mechanisms involved in the therapeutic effects of Regorafenib in HCC and the impact of METTL14 and CHOP on Regorafenib treatment, we employed shRNA/overexpression approaches to transfect METTL14 and CHOP genes, as well as conducted in vivo experiments. RESULTS: Treatment with Regorafenib led to a notable decrease in viability and proliferation of SK-Hep-1 and HCC-LM3 cells. The expression level of CHOP was upregulated after Regorafenib intervention, and CHOP underwent m6A methylation. Among the m6A methylation-related proteins, METTL14 exhibited the most significant downregulation. Mechanistic studies revealed that Regorafenib regulated the cell cycle arrest in HCC through METTL14-mediated modulation of CHOP, and the METTL14/CHOP axis affected the sensitivity of HCC to Regorafenib. In vivo, CHOP enhanced the anticancer effect of Regorafenib. CONCLUSION: The inhibition of HCC development by Regorafenib is attributed to its modulation of m6A expression of CHOP, mediated by METTL14, and the METTL14/CHOP axis enhances the sensitivity of HCC to Regorafenib. These findings provide insights into the treatment of HCC and the issue of drug resistance to Regorafenib.


Assuntos
Adenosina/análogos & derivados , Carcinoma Hepatocelular , Pontos de Checagem do Ciclo Celular , Neoplasias Hepáticas , Metiltransferases , Compostos de Fenilureia , Piridinas , Fator de Transcrição CHOP , Humanos , Piridinas/farmacologia , Piridinas/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Camundongos , Animais , Linhagem Celular Tumoral , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Metiltransferases/metabolismo , Metiltransferases/genética , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição CHOP/genética , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus
2.
Small ; : e2305764, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368252

RESUMO

Photothermal therapy (PTT) is a new treatment modality for tumors. However, the efficient delivery of photothermal agents into tumors remains difficult, especially in hypoxic tumor regions. In this study, an approach to deliver melanin, a natural photothermal agent, into tumors using genetically engineered bacteria for image-guided photothermal and immune therapy is developed. An Escherichia coli MG1655 is transformed with a recombinant plasmid harboring a tyrosinase gene to produce melanin nanoparticles. Melanin-producing genetically engineered bacteria (MG1655-M) are systemically administered to 4T1 tumor-bearing mice. The tumor-targeting properties of MG1655-M in the hypoxic environment integrate the properties of hypoxia targeting, photoacoustic imaging, and photothermal therapeutic agents in an "all-in-one" manner. This eliminates the need for post-modification to achieve image-guided hypoxia-targeted cancer photothermal therapy. Tumor growth is significantly suppressed by irradiating the tumor with an 808 nm laser. Furthermore, strong antitumor immunity is triggered by PTT, thereby producing long-term immune memory effects that effectively inhibit tumor metastasis and recurrence. This work proposes a new photothermal and immune therapy guided by an "all-in-one" melanin-producing genetically engineered bacteria, which can offer broad potential applications in cancer treatment.

3.
Int J Nanomedicine ; 18: 4871-4884, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662687

RESUMO

Purpose: Ultrasound molecular imaging (UMI) has proven promising to diagnose the onset and progression of diseases such as angiogenesis, inflammation, and thrombosis. However, microbubble-based acoustic probes are confined to intravascular targets due to their relatively large particle size, greatly reducing the application value of UMI, especially for extravascular targets. Extradomain B fibronectin (ED-B FN) is an important glycoprotein associated with tumor genesis and development and highly expressed in many types of tumors. Here, we developed a gas vesicles (GVs)-based nanoscale acoustic probe (ZD2-GVs) through conjugating ZD2 peptides which can specially target to ED-B FN to the biosynthetic GVs. Materials and Methods: ED-B FN expression was evaluated in normal liver and tumor tissues with immunofluorescence and Western blot. ZD2-GVs were prepared by conjugating ZD2 to the surface of GVs by amide reaction. The inverted microscope was used to analyze the targeted binding capacity of ZD2-GVs to MB49 cells (bladder cancer cell line). The contrast-enhanced imaging features of GVs, non-targeted control GVs (CTR-GVs), and targeted GVs (ZD2-GVs) were compared in three MB49 tumor mice. The penetration ability of ZD2-GVs in tumor tissues was assessed by fluorescence immunohistochemistry. The biosafety of GVs was evaluated by CCK8, blood biochemistry, and HE staining. Results: Strong ED-B FN expression was observed in tumor tissues while little expression in normal liver tissues. The resulting ZD2-GVs had only 267.73 ± 2.86 nm particle size and exhibited excellent binding capability to the MB49 tumor cells. The in vivo UMI experiments showed that ZD2-GVs produced stronger and longer retention in the BC tumors than that of the non-targeted CTR-GVs and GVs. Fluorescence immunohistochemistry confirmed that ZD2-GVs could penetrate the tumor vascular into the interstitial space of the tumors. Biosafety analysis revealed there was no significant cytotoxicity to these tested mice. Conclusion: Thus, ZD2-GVs can function as a potential UMI probe for the early diagnosis of bladder cancer.


Assuntos
Fibronectinas , Neoplasias da Bexiga Urinária , Animais , Camundongos , Ultrassonografia , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Imagem Molecular , Acústica
4.
Sci Rep ; 12(1): 5712, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35383254

RESUMO

Pulmonary cryptococcosis (PC) is a common fungal infectious disease, and infection can occur in patients with any immune function. To better understand PC, we compared the CT findings and histopathological results in immunocompetent and immunocompromised patients. The clinical data of 68 patients with PC were collected retrospectively and divided into the immunocompetent group and immunocompromised group. The clinical characteristics, CT manifestations and histopathological characteristics of the two groups of patients were compared. Forty-two patients (61.8%) were immunocompetent, and 26 patients (38.2%) were immunocompromised. Compared with immunocompromised patients, 57.14% (24/42) of immunocompetent patients were asymptomatic (p = 0.002). Compared with immunocompetent patients, cough (14/26, 53.9%) and fever (13/26, 50.0%) were the main symptoms in immunocompromised patients (p = 0.044, p = 0.007). Nodular lesions (97.6%, 41/42) were the most common CT type in immunocompetent patients, and the CT characteristic was a single lesion (25/42, 59.5%); the main histopathological type was nodular fibrogranuloma (30/42, 71.4%), and the main histopathological characteristic was inflammatory granuloma (31/42, 73.81%) formed by macrophage phagocytosis of Cryptococcus. Consolidation (15/26, 57.7%) was more common in the CT type of immunocompromised patients. Multiple lesions (24/26, 92.31%), air bronchial signs (19/26, 73.081%) and cavities (9/26, 34.62%) were the main CT characteristics. The mucinous colloid type (19/26, 73.1%) was its main histopathological type, which was mainly characterized by a small amount of surrounding inflammatory cell infiltration (17/26, 65.4%). There were significant differences in the classification and characteristics of CT and pathology between the two groups (p < 0.05). Through the CT manifestations and histopathological characteristics of PC under different immune function states, it was found that immune function has a significant impact on the CT manifestations and histopathological characteristics of patients with PC.


Assuntos
Criptococose , Pneumopatias Fúngicas , Humanos , Hospedeiro Imunocomprometido , Pneumopatias Fúngicas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
5.
Zhonghua Zhong Liu Za Zhi ; 37(8): 603-8, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26714601

RESUMO

OBJECTIVE: The aim of this study was to investigate the expression of microRNA-100 (miR-100) and its relation with prognosis in colorectal cancer (CRC). METHODS: The expression of miR-100 was analyzed by quantitative real-time PCR (qRT-PCR) in 172 CRC tissue samples. The relation of miR-100 expression patterns with clinical pathological significance in CRC was analyzed. The effects of alterations of miR-100 expression and its consequences on CRC cell proliferation, apoptosis and migration were demonstrated in cells cultured in vitro. RESULTS: The relative expression of miR-100 in CRC tissues and peritumoral tissues were -6.185 ± 1.921 and -3.698 ± 1.786, respectively, with a significant difference between the two groups (P<0.01). There was a significant difference between the relative expression of miR-100 in CRC with lymph node metastasis (-5.706 ± 1.809) and without lymph node metastasis (-6.775 ± 1.902, P<0.01). The relative expression of miR-100 in tumors of different TNM stages were -7.267 ± 1.888 in stage I, -6.443 ± 1.859 in stage II, -5.923 ± 1.796 in stage III, and -4.639 ± 1.516 in stage IV, with a significant difference among them (P<0.01). Different differentiation grades showed different expression of miR-100, i.e. -7.389 ± 1.828 in well differentiated tumors, -6.095 ± 1.843 in moderately differentiated tumors, and -5.476 ± 2.088 in poorly differentiated tumors (P<0.01). There was no significant correlation between miR-100 expression and overall survival rates of the CRC patients (P=0.179). Overexpression of miR-100 in the CRC cell line HCT-8 inhibited cell proliferation, but promoted cell apoptosis and migration. CONCLUSIONS: The expression of miR-100 is correlated with lymph node metastasis, TNM stage and differentiation grade, and may be a potential biomarker indicating the development of CRC.


Assuntos
Neoplasias Colorretais/metabolismo , MicroRNAs/metabolismo , Apoptose , Diferenciação Celular , Proliferação de Células , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Estadiamento de Neoplasias , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real
6.
Nutr Cancer ; 67(7): 1151-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26359675

RESUMO

Epidemiological and experimental evidence supports the key role of diet in the development of many types of cancer. Recent studies have suggested that dietary modifications may be beneficial for individuals at high risk for hepatocellular carcinoma (HCC). In this study, we investigated the effect of a high-protein (HP; 20% casein) dietondiethylnitrosamine (DEN)-induced hepatocarcinogenesis. Mice were given free access to water with 30 µg/ml DEN and fed a normal or HP diet for 22 wk. The results showed mice consuming HP diets had reduced mortality rates and body weights and lower hepatic enzyme activity compared to DEN-treated mice on a normal diet. HP consumption also promoted collagen accumulation in the liver, and reduced numbers of proliferating hepatocytes and infiltrating inflammatory cells, as well as decreased expression of inflammatory factor interleukin-1ß, and nuclear factor κB activation. These data indicate that HP diets can inhibit DEN-induced hepatocarcinogenesis via suppression of the inflammatory response and provide a new evidence for the dietary management of clinical patients with hepatocellular carcinoma.


Assuntos
Proteínas Alimentares/farmacologia , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/dietoterapia , Animais , Caseínas/farmacologia , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Proteínas Alimentares/química , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Interleucina-1beta/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/mortalidade , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos Endogâmicos C3H , NF-kappa B/metabolismo , Taxa de Sobrevida
7.
Comput Biol Chem ; 52: 1-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25086506

RESUMO

Long noncoding RNAs (lncRNAs) play essential regulatory roles in the human cancer genome. Many identified lncRNAs are transcribed by RNA polymerase II in which they are polyadenylated, whereby the long intervening noncoding RNAs (lincRNAs) have been widely used for the researches of lncRNAs. To date, the mechanism of lincRNAs polyadenylation related to cancer is rarely fully understood yet. In this paper, first we reported a comprehensive map of global lincRNAs polyadenylation sites (PASs) in five human cancer genomes; second we proposed a grouping method based on the pattern of genes expression and the manner of alternative polyadenylation (APA); third we investigated the distribution of motifs surrounding PASs. Our analysis reveals that about 70% of PASs are located in the sense strand of lincRNAs. Also more than 90% PASs in the antisense strand of lincRNAs are located in the intron regions. In addition, around 40% of lincRNA genes with PASs has APA sites. Four obvious motifs i.e., AATAAA, TTTTTTTT, CCAGSCTGG, and RGYRYRGTGG were detected in the sequences surrounding PASs in the normal and cancer tissues. Furthermore, a novel algorithm was proposed to recognize the lincRNAs PASs of tumor tissues based on support vector machine (SVM). The algorithm can achieve the accuracies up to 96.55% and 89.48% for identification the tumor lincRNAs PASs from the non-polyadenylation sites and the non-lincRNA PASs, respectively.


Assuntos
Neoplasias/genética , Poliadenilação , RNA Longo não Codificante , Mama/metabolismo , Colo/metabolismo , Feminino , Genoma Humano , Humanos , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Máquina de Vetores de Suporte
8.
Artigo em Inglês | MEDLINE | ID: mdl-25571055

RESUMO

Polyadenylation including the cleavage of pre-mRNA and addition of a stretch of adenosines to the 3'-end is an essential step of pre-mRNA processing in eukayotes. The known regulatory role of polyadenylation in mRNA localization, stability, and translation and the emerging link between poly(A) and disease states underline the necessary to fully characterize polyadenylation sites. Several artificial intelligence methods have been proposed for poly(A) sites recognition. However, these methods are suitable to small subsets of genome sequences. It is necessary to propose a method for genome-wide recognition of poly(A) sites. Recent efforts have found a lot of poly(A) related factors on DNA level. Here, we proposed a novel genome-wide poly(A) recognition method based on the Condition Random Field (CRF) by integrating multiple features. Compared with the polya_svm (the most accurate program for prediction of poly(A) sites till date), our method had a higher performance with the area under ROC curve(0.8621 versus 0.6796). The result suggests that our method is an effective method in genome wide poly(A) sites recognition.


Assuntos
Genoma Humano , Poli A/análise , Regiões 3' não Traduzidas , Algoritmos , Área Sob a Curva , Inteligência Artificial , Sequência de Bases , Ilhas de CpG , Histonas/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Curva ROC , Máquina de Vetores de Suporte
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