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1.
Biochem Pharmacol ; 222: 116102, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428828

RESUMO

Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, has known as one of the most significant pathological processes involved in diabetic kidney disease (DKD). Stimulator of interferon genes (STING) has been demonstrated its potential in regulating ferroptosis, but the regulatory role in DKD mice and underlying mechanisms haven't been illustrated. To elucidate whether and how STING regulates ferroptosis in DKD, we detected the influence of STING on diabetic-related ferroptosis in a diabetic model and in erastin-induced renal tubular epithelial cells (RTECs). Our study demonstrated that STING was abnormally activated and promoted ferroptosis in DKD. STING deficiency alleviated renal pathologic damages and disfunction in diabetic mice via alleviating ferroptosis and reducing oxidative stress. Mechanismly, STING inhibition was shown to improve ferroptosis and reduce oxidative stress in erastin-induced RTECs. The disruption of ferroportin1 (FPN1) on the basis of STING inhibition abolished the improvements in ferroptosis and promoted reactive oxygen species (ROS) generation. Further, STING inhibition alleviated ferroptosis via stabilizing FPN1 protein level by decreasing ubiquitinated FPN1 for proteasomal degradation. In conclusion, STING deficiency protected against diabetic renal injury via alleviating ferroptosis through stabilizing FPN1 and reducing oxidative stress, providing a possible potential approach for the treatment of DKD.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Ferroptose , Animais , Camundongos , Morte Celular , Diabetes Mellitus Experimental/complicações , Rim
2.
Cancer Res ; 84(6): 827-840, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38241695

RESUMO

N6-methyladenosine (m6A) RNA modification is the most common and conserved epigenetic modification in mRNA and has been shown to play important roles in cancer biology. As the m6A reader YTHDF1 has been reported to promote progression of hepatocellular carcinoma (HCC), it represents a potential therapeutic target. In this study, we evaluated the clinical significance of YTHDF1 using human HCC samples and found that YTHDF1 was significantly upregulated in HCCs with high stemness scores and was positively associated with recurrence and poor prognosis. Analysis of HCC spheroids revealed that YTHDF1 was highly expressed in liver cancer stem cells (CSC). Stem cell-specific conditional Ythdf1 knockin (CKI) mice treated with diethylnitrosamine showed elevated tumor burden as compared with wild-type mice. YTHDF1 promoted CSCs renewal and resistance to the multiple tyrosine kinase inhibitors lenvatinib and sorafenib in patient-derived organoids and HCC cell lines, which could be abolished by catalytically inactive mutant YTHDF1. Multiomic analysis, including RNA immunoprecipitation sequencing, m6A methylated RNA immunoprecipitation sequencing, ribosome profiling, and RNA sequencing identified NOTCH1 as a direct downstream of YTHDF1. YTHDF1 bound to m6A modified NOTCH1 mRNA to enhance its stability and translation, which led to increased NOTCH1 target genes expression. NOTCH1 overexpression rescued HCC stemness in YTHDF1-deficient cells in vitro and in vivo. Lipid nanoparticles targeting YTHDF1 significantly enhanced the efficacy of lenvatinib and sorafenib in HCC in vivo. Taken together, YTHDF1 drives HCC stemness and drug resistance through an YTHDF1-m6A-NOTCH1 epitranscriptomic axis, and YTHDF1 is a potential therapeutic target for treating HCC. SIGNIFICANCE: Inhibition of YTHDF1 expression suppresses stemness of hepatocellular carcinoma cells and enhances sensitivity to targeted therapies, indicating that targeting YTHDF1 may be a promising therapeutic strategy for liver cancer.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Compostos de Fenilureia , Quinolinas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Sorafenibe , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Adenosina/farmacologia , RNA Mensageiro , RNA , Receptor Notch1/genética , Proteínas de Ligação a RNA/genética
3.
Cell Biosci ; 13(1): 63, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949517

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) metastasis and recurrence lead to therapy failure, which are closely associated with the proteome. However, the role of post-translational modification (PTM) in HCC, especially for the recently discovered lysine crotonylation (Kcr), is elusive. RESULTS: We investigated the correlation between crotonylation and HCC in 100 tumor tissues and performed stable isotope labeling by amino acids and liquid chromatography tandem mass spectrometry in HCC cells, and we found that crotonylation was positively correlated with HCC metastasis, and higher crotonylation in HCC cells facilitated cell invasiveness. Through bioinformatic analysis, we found that the crotonylated protein SEPT2 was significantly hypercrotonylated in highly invasive cells, while the decrotonylated mutation of SEPT2-K74 impaired SEPT2 GTPase activity and inhibited HCC metastasis in vitro and in vivo. Mechanistically, SIRT2 decrotonylated SEPT2, and P85α was found to be the downstream effector of SEPT2. Moreover, we identified that SEPT2-K74cr was correlated with poor prognosis and recurrence in HCC patients, thus indicating its clinical potential as an independent prognostic factor. CONCLUSIONS: We revealed the role of nonhistone protein crotonylation in regulating HCC metastasis and invasion. Crotonylation facilitated cell invasion through the crotonylated SEPT2-K74-P85α-AKT pathway. High SEPT2-K74 crotonylation predicted poor prognosis and a high recurrence rate in HCC patients. Our study revealed a novel role of crotonylation in promoting HCC metastasis.

4.
Bioresour Technol ; 369: 128462, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36503087

RESUMO

This study evaluated the compostability of rice straw as the main feedstock (75 % in dry weight), supplemented with three different nitrogen-rich wastes, namely food waste (FW), dairy manure (DM), and sewage sludge (SS). Organic matter (OM) degradation, maturity and fertility of the end-product, and bacterial community structure during the composting processes were compared. All composting processes generated mature end-product within 51 days. Notably, FW addition was more effective to accelerate rice straw OM degradation and significantly improved end-product fertility with a high yield of Chinese cabbage. The succession of the bacterial community was accelerated with FW supplementation. Genera Geobacillus, Chryseolinea, and Blastocatella were significantly enriched during the composting of rice straw with FW supplementation. Finally, temperature, total nitrogen, moisture, pH, and total carbon were the key factors affecting microorganisms. This study provides a promising alternative method to enhance the disposal of larger amounts of rice straw in a shorter time.


Assuntos
Compostagem , Oryza , Eliminação de Resíduos , Nitrogênio/metabolismo , Oryza/metabolismo , Solo/química , Bactérias/metabolismo , Esterco/microbiologia , Suplementos Nutricionais , Esgotos
5.
Hepatology ; 75(5): 1123-1138, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34435708

RESUMO

BACKGROUND AND AIMS: Androgen receptor (AR) has been reported to play an important role in the development and progression of man's prostate cancer. Hepatocellular carcinoma (HCC) is also male-dominant, but the role of AR in HCC remains poorly understood. Mechanistic target of rapamycin complex 1 (mTORC1) also has been reported to be highly activated in HCC. In this study, we aimed to explore the role of AR phosphorylation and its relationship with mTORC1 in hepatocarcinogenesis. APPROACH AND RESULTS: In vitro experiment, we observed that mTORC1 interacts with hepatic AR and phosphorylates it at S96 in response to nutrient and mitogenic stimuli in HCC cells. S96 phosphorylation promotes the stability, nuclear localization, and transcriptional activity of AR, which enhances de novo lipogenesis and proliferation in hepatocytes and induces liver steatosis and hepatocarcinogenesis in mice independently and cooperatively with androgen. Furthermore, high ARS96 phosphorylation is observed in human liver steatotic and HCC tissues and is associated with overall survival and disease-free survival, which has been proven as an independent survival predictor for patients with HCC. CONCLUSIONS: AR S96 phosphorylation by mTORC1 drives liver steatosis and HCC development and progression independently and cooperatively with androgen, which not only explains why HCC is man-biased but also provides a target molecule for prevention and treatment of HCC and a potential survival predictor in patients with HCC.


Assuntos
Carcinoma Hepatocelular , Fígado Gorduroso , Neoplasias Hepáticas , Androgênios , Animais , Carcinogênese , Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica , Humanos , Neoplasias Hepáticas/patologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Fosforilação , Receptores Androgênicos/metabolismo
6.
Waste Manag ; 135: 130-139, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34496309

RESUMO

Aerobic composting is a promising alternative for the recycling of rice straw (RS), and an applicable nitrogen source is necessary to improve the process. The aim of this study was to compare the performance and microbial community dynamics of RS composting using urea or protein hydrolysate from leather waste (PHL) as a nitrogen source. Results showed that PHL addition achieved a faster temperature increase rate at start-up (1.85 ℃·h-1 vs 1.07 ℃·h-1), higher volatile solid degradation efficiency (48.04% vs 46.98%), and greater germination indices (111.72% vs 89.87%) in the end products, as compared to urea. The major bacterial phyla included Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria in both composting processes. Although the bacterial communities in both processes succeeded in a similar pattern according to different composting phases, PHL addition accelerated the succession rate of the microbial community. Co-occurrence network analysis revealed that bacterial community composition was strongly correlated with physicochemical properties such as dissolved organic carbon (DOC), NH4+, pH, temperature, and total nitrogen (TN) content. These results proved the potential of using PHL as a nitrogen source to improve the RS composting process.


Assuntos
Compostagem , Microbiota , Oryza , Esterco , Nitrogênio/análise , Hidrolisados de Proteína , Solo , Ureia
8.
Aging (Albany NY) ; 12(12): 12187-12205, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32544882

RESUMO

Recent studies demonstrate that immune checkpoint inhibitor (ICI) therapy has achieved success in many types of advanced cancers including advanced hepatocellular carcinoma (HCC). However, ICI therapy is beneficial in only some HCC patients, suggesting that immune-responses are highly variable in HCCs. Therefore, understanding the immune status in HCC microenvironment will facilitate ICI immunotherapy and guide patient selection for the therapy. In this study, we first analyzed the expression profile of immune-modulating genes and their relationship with survival of HCC patients using the data downloaded from The Cancer Genome Atlas - Liver Hepatocellular Carcinoma (TCGA-LIHC) database, and found that the higher expressions of CD276 (B7-H3) and CD47 were significantly associated with poor survival. Then we identified 4 immune subtypes of HCCs with different survivals by using the combination expression of B7-H3 (or CD47) and CD8. Patients with B7-H3low/CD8high or CD47low/CD8high have the best survival while ones with B7-H3high/CD8low or CD47high/CD8low have the worst survival. The 4 immune subtypes were validated in another 72 HCC patients obtained from South China. In conclusion, our findings suggest that HCC patient prognosis is associated with immunophenotypes by T cell infiltration (CD8 expression) and the expression of the adaptive immune resistance gene (B7-H3 or CD47), and this immune classification system will facilitate HCC patient selection for ICI immunotherapy.


Assuntos
Antígenos B7/metabolismo , Antígeno CD47/metabolismo , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos T/metabolismo , Adulto , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , China/epidemiologia , Conjuntos de Dados como Assunto , Progressão da Doença , Feminino , Hepatectomia , Humanos , Imunoterapia , Estimativa de Kaplan-Meier , Fígado/imunologia , Fígado/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Prognóstico , RNA-Seq , Estudos Retrospectivos , Linfócitos T/imunologia , Microambiente Tumoral/imunologia
9.
Food Funct ; 11(6): 5156-5165, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32432601

RESUMO

Liver fibrosis is a histological change that often occurs due to hepatic stellate cell (HSC) activation and excessive formation of an extracellular matrix in the liver. Pelargonidin (PEL) is a natural anthocyanidin existing in blueberries, berries, strawberries, and red radishes and has been demonstrated to possess health beneficial effects. Herein, we investigated the effect of PEL on liver fibrosis induced by CCl4 and hepatic stellate cells induced by transforming growth factor-ß (TGF-ß). We found that PEL administration prevented liver injury and liver fibrosis induced by CCl4 in a dose-dependent manner. Further data revealed that PEL increased liver nuclear factor E2-related factor 2 (Nrf2) and reduced liver oxidative stress and the expression levels of NLRP3, caspase-1 and IL-1ß. In TGF-ß-challenged HSCs (LX-2 cells), PEL effectively inhibited the LX-2 cell activation. In addition, the anti-fibrosis effects of PEL in LX-2 cells were abolished by Nrf2 knockdown. In summary, our study demonstrated that PEL ameliorated CCl4-induced liver fibrosis and HSC activation induced by TGF-ß. The possible molecular mechanisms of PEL in liver fibrosis may be attributed to its suppression of ROS-NLRP3-IL-1ß signaling by Nrf2 activation.


Assuntos
Antocianinas/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Fígado/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Actinas/metabolismo , Animais , Tetracloreto de Carbono , Linhagem Celular , Colágeno/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta/metabolismo
10.
Bioresour Technol ; 306: 123091, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32169511

RESUMO

The aim of this work was to study the dynamic change in structure and potential function of bacterial community during dairy manure composting process using high-throughput sequencing and advanced bioinformatics tools. Alpha diversity of microbial community significantly decreased during the thermophilic phase and then recovered gradually. Beta diversity analysis showed unique community structures in different composting phases. Keystone microbes such as genus Corynebacterium, Bacillus, Luteimonas and Nonomuraea were identified for different composting phases. Six functional modules were identified for bacterial community during the composting process using co-occurrence analysis. These modules were significantly associated with temperature, pH, degradation of organic matter and maturation of compost. Predicted metagenomics analysis showed that the relative abundance of amino acid, lipid, energy and xenobiotics metabolism increased during the composting process. These results provide valuable insights into the microbiota during dairy manure composting and how the structures and metabolic functions changed in response to composting phases.

11.
J Cancer ; 10(18): 4178-4188, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413736

RESUMO

Gastric cancer (GC) is a leading global health problem as it is the fifth most common cancer type and the third most common cause of cancer-related deaths worldwide. In most areas of the world, the incidence rate of GC is 1.5- to 3-fold higher in males than in females. The androgen receptor (AR) is an independent adverse prognostic factor in patients with GC. However, the mechanism by which AR regulates the progression of GC remains unclear. In this study, we found that AR expression was upregulated in 6/8 GC cell lines, and this expression was higher than that in immortalized gastric cells. AR expression was also higher in GC tissues than in adjacent tissues. Moreover, the ectopic expression of AR promoted the colony formation ability, migration and invasion of GC cells. In contrast, AR knockdown had the opposite effects on GC cell lines. Remarkably, we found that AR regulated cell cycle-related kinase (CCRK) expression through transcriptional mechanisms. The AR-CCRK axis promoted GC development through the phosphorylation of GSK3ß and ß-catenin. Furthermore, TCGA data revealed that high expression of AR or CCRK was related to poor prognosis in GC patients. The prognosis was significantly worse in patients with concurrent high AR and CCRK expression than in patients with low AR and CCRK expression. In conclusion, our study demonstrated that AR and CCRK acted as oncogenes in GC progression. However, their clinical roles require further exploration.

12.
Pharmacol Res ; 149: 104352, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31323332

RESUMO

Mammalian / mechanistic target of rapamycin (mTOR) is a critical sensor of environmental cues that regulates cellular macromolecule synthesis and metabolism in eukaryotes. DNA methylation is the most well-studied epigenetic modification that is capable of regulating gene transcription and affecting genome stability. Both dysregulation of mTOR signaling and DNA methylation patterns have been shown to be closely linked to tumor progression and serve as promising targets for cancer therapy. Although their respective roles in tumorigenesis have been extensively studied, whether molecular interplay exists between them is still largely unknown. In this review, we provide a brief overview of mTOR signaling, DNA methylation as well as related serine and one-carbon metabolism, one of the most critical aspects of metabolic reprogramming in cancer. Based on the latest understanding regarding the regulation of metabolic processes by mTOR signaling as well as interaction between metabolism and epigenetics, we further discuss how serine and one-carbon metabolism may serve as a bridge that links mTOR signaling and DNA methylation to promote tumor growth. Elucidating their relationship may provide novel insight for cancer therapy in the future.


Assuntos
Metilação de DNA , Neoplasias/genética , Serina/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/metabolismo , Serina/genética , Serina-Treonina Quinases TOR/genética
13.
Acta Biochim Pol ; 65(3): 465-470, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30188965

RESUMO

Inflammation plays an important role in the development of many obesity-related diseases. This study aimed to investigate the effect of ezetimibe on inflammation and myocardial remodeling in obese rats. A rat model of obesity was established, and myocardial damage was examined by transmission electron microscopy and Masson staining. Twenty obese rats were divided into two groups (n=10): obese group and ezetimibe group. Ten SD rats were used as controls. Western blot was performed to monitor the expression of P-p38MAPK and interleukin (IL)-6. Immunohistochemical staining was used to monitor the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. In the obese rats group, we observed increased inflammatory factors and myocardial hypertrophy. In contrast, the ezetimibe group exhibited decreased expression of inflammatory factors and an improvement in myocardial remodeling compared to the obese group. Mechanistically, we found that ezetimibe decreased P-p38MAPK, IL-6, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 levels in the hearts of the obese rats. Taken together, these results indicate that ezetimibe may improve myocardial remodeling in obese rats by inhibiting inflammation.


Assuntos
Anticolesterolemiantes/farmacologia , Ezetimiba/farmacologia , Coração/efeitos dos fármacos , Inflamação/prevenção & controle , Obesidade/fisiopatologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Western Blotting , Proteína C-Reativa/metabolismo , Cardiomegalia/etiologia , Colágeno/metabolismo , Dieta Hiperlipídica , Inflamação/complicações , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Masculino , Miocárdio/metabolismo , Obesidade/complicações , Ratos Sprague-Dawley , Molécula 1 de Adesão de Célula Vascular/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Mol Cancer Ther ; 17(12): 2610-2621, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30224431

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common and deadly human cancers. The 5-year survival rate is very low. Unfortunately, there are few efficacious therapeutic options. Until recently, Sorafenib has been the only available systemic drug for advanced HCC. However, it has very limited survival benefits, and new therapies are urgently needed. In this study, we investigated the anti-HCC activity of carfilzomib, a second-generation, irreversible proteasome inhibitor, as a single agent and in combination with sorafenib. In vitro, we found that carfilzomib has moderate anticancer activity toward liver cancer cells, but strongly enhances the ability of sorafenib to suppress HCC cell growth, proliferation, migration, invasion, and survival. Remarkably, the drug combination exhibits even more potent antitumor activity when tested in animal tumor models. Mechanistically, the combined treatment activates caspase-dependent and endoplasmic reticulum stress/CHOP-mediated apoptotic pathways, and suppresses epithelial-mesenchymal transition. In conclusion, our results demonstrate that the combination of carfilzomib and sorafenib has synergistic antitumor activities against HCC, providing a potential therapeutic strategy to improve the mortality and morbidity of HCC patients.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Oligopeptídeos/farmacologia , Sorafenibe/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Cancer ; 9(16): 2807-2816, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123349

RESUMO

Using genome-wide screening and TCGA-based data analysis, we identified a DNA methylation-related gene named metallothionein-1G (MT1G), which may play an important role in hepatocellular carcinoma (HCC). In this study, we found that MT1G expression was silenced in 4/6 HCC cell lines and negatively related to aberrant promoter hypermethylation. Its mRNA level was restored with demethylation treatment. Moreover, MT1G downregulation at both the transcriptional and protein level was also detected in 8 pairs of clinical HCC samples compared with its expression in adjacent normal tissues. Ectopic expression of MT1G in silenced HCC cell lines inhibited colony formation, suppressed cell migration and invasion, and repressed xenograft tumor growth in nude mice. In contrast, knockdown of MT1G by short hairpin RNA showed the opposite effect on cell proliferation and the malignant phenotype. Moreover, our data showed that MT1G suppressed tumor invasion and metastasis mainly through regulating the expression of proteins in the matrix metalloproteinase family (MMP) and modulating the epithelial-mesenchymal transition (EMT) process. To our surprise, the data from TCGA showed that hypermethylation of MT1G is associated with good survival of HCC patients. In conclusion, our study demonstrated that MT1G acts as a tumor suppressor gene in HCC development, but its clinical potential in HCC requires further evaluation.

16.
IEEE Trans Neural Netw Learn Syst ; 29(11): 5408-5418, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29994740

RESUMO

This paper considers a least square regularized regression algorithm for multi-task learning in a union of reproducing kernel Hilbert spaces (RKHSs) with Gaussian kernels. It is assumed that the optimal prediction function of the target task and those of related tasks are in an RKHS with the same but with unknown Gaussian kernel width. The samples for related tasks are used to select the Gaussian kernel width, and the sample for the target task is used to obtain the prediction function in the RKHS with this selected width. With an error decomposition result, a fast learning rate is obtained for the target task. The key step is to estimate the sample errors of related tasks in the union of RKHSs with Gaussian kernels. The utility of this algorithm is illustrated with one simulated data set and four real data sets. The experiment results illustrate that the underlying algorithm can result in significant improvements in prediction error when few samples of the target task and more samples of related tasks are available.

17.
Hepatology ; 67(6): 2271-2286, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29220539

RESUMO

Hepatocellular carcinoma (HCC) is a male-dominant cancer, and androgen receptor (AR) has been linked to the pathogenesis of HCC. However, AR expression and its precise role in HCC remain controversial. Moreover, previous antiandrogen and anti-AR clinical trials in HCC failed to demonstrate clinical benefits. In this study, we found that AR is overexpressed in the nucleus of approximately 37% of HCC tumors, which is significantly associated with advanced disease stage and poor survival. AR overexpression in HCC cells markedly alters AR-dependent transcriptome, stimulates oncogenic growth, and determines therapeutic response to enzalutamide, a second generation of AR antagonist. However, AR inhibition evokes feedback activation of AKT-mTOR (mechanistic target of rapamycin) signaling, a central regulator for cell growth and survival. On the other hand, mTOR promotes nuclear AR protein expression by restraining ubiquitin-dependent AR degradation and enhancing AR nuclear localization, providing a mechanistic explanation for nuclear AR overexpression in HCC. Finally, cotargeting AR and mTOR shows significant synergistic anti-HCC activity and decreases tumor burden by inducing apoptosis in vivo. CONCLUSION: Nuclear AR overexpression is associated with the progression and prognosis of HCC. However, enzalutamide alone has limited therapeutic utility attributed to feedback activation of the AKT-mTOR pathway. Moreover, mTOR drives nuclear AR overexpression. Cotargeting AR and mTOR is a promising therapeutic strategy for HCC. (Hepatology 2018;67:2271-2286).


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Receptor Cross-Talk , Receptores Androgênicos/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Benzamidas , Carcinoma Hepatocelular/tratamento farmacológico , Núcleo Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/uso terapêutico , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Células Tumorais Cultivadas
18.
Cell Cycle ; 16(18): 1673-1682, 2017 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-28841361

RESUMO

p53R2 is a p53-inducible ribonucleotide reductase subunit involved in deoxyribonucleotide biosynthesis and DNA repair. Although p53R2 has been linked to human cancer, its role in cervical cancer remains unknown. In this study, we investigated the expression and clinical significance of p53R2 in early-stage cervical cancer. p53R2 expression is significantly upregulated at both mRNA and protein levels in cervical cancer cells and tissues, compared with that in matched normal cervical cells and tissues, respectively. p53R2 overexpression is associated with increased risk of pelvic lymph node metastasis (PLNM, p = 0.001) and cancer relapse (p = 0.009). Patients with high p53R2 expression have a shorter overall survival (OS) and disease-free survival (DFS). p53R2 is an independent factor for predicting OS and DFS of cervical cancer patients. We further show that p53R2 is important for oncogenic growth, migration and invasion in cervical cancer cells. Mechanistically, p53R2 promotes Akt signaling and epithelial-mesenchymal transition (EMT). In conclusion, our study demonstrates for the first time that p53R2 protein is overexpressed in early-stage cervical cancer and unravels some unconventional oncogenic functions of p53R2. p53R2 may be a useful prognostic biomarker and therapeutic target for cervical cancer.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Progressão da Doença , Transição Epitelial-Mesenquimal , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ribonucleotídeo Redutases/metabolismo , Transdução de Sinais , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Análise de Sobrevida
19.
Aging (Albany NY) ; 9(3): 914-931, 2017 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-28316326

RESUMO

Rab1B has recently been reported to be involved in human cancer, but the role of Rab1B in colorectal cancer (CRC) remains unclear. In this study, we investigated the expression of Rab1B and MMP9 in CRC by qRT-PCR, immunoblot and immunohistochemistry and analyzed the clinical significance. The results show that Rab1B and MMP9 are increased at both mRNA and protein levels in CRC cell lines and tissues, as measured by qRT-PCR and immunoblotting. The high protein expression of Rab1B and MMP9 in 179 CRC tissues is associated with deep tumor invasion, lymph-node metastasis and advanced TNM stage. Survival analysis indicates that patients with overexpression of Rab1B or MMP9 have significantly worse overall survival and progression-free survival, but better response to chemotherapy than those with low expression of proteins, and that Rab1B is an independent prognostic factor for CRC patients. Furthermore, when Rab1B and MMP9 are combined into a new risk model, it has a remarkably better prediction of prognosis than each protein alone. In conclusion, Rab1B and MMP9 are potential prognostic biomarkers and their combination significantly improves predictive power for survival and chemotherapy response in CRC patients.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/mortalidade , Metaloproteinase 9 da Matriz/metabolismo , Proteínas rab1 de Ligação ao GTP/metabolismo , Idoso , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento , Proteínas rab1 de Ligação ao GTP/genética
20.
J Res Med Sci ; 21: 4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27904550

RESUMO

BACKGROUND: To investigate the relation between serum leptin levels and cerebral infarction (CI) by meta-analysis. MATERIALS AND METHODS: Scientific literature databases were searched for studies published in Chinese and English. After retrieving relevant articles through database searches and screening using predefined selection criteria, high-quality studies related to our research topic were selected for inclusion in this meta-analysis. All statistical analyses were conducted using Comprehensive Meta-Analysis 2.0 (CMA 2.0, Biostat Inc., Englewood, New Jersey, USA). RESULTS: The study results revealed that serum leptin levels were significantly higher in CI patients as compared to normal controls. The outcomes of subgroup analysis by ethnicity suggested that the serum leptin levels in CI patients were significantly higher than normal controls in both Asian and Caucasian populations. Further, subgroup analysis based on the detection method indicated that the serum leptin levels in CI patients were significantly higher compared with normal controls when measured by radioimmunoassay (RIA) but enzyme-linked immunosorbent assay (ELISA)-based measurements did not show such statistically significant differences. CONCLUSION: Our meta-analysis results suggest that serum leptin levels in CI patients may be closely correlated with CI risks.

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