RESUMO
Low glucose is a common microenvironment for rapidly growing solid tumors, which has developed multiple approaches to survive under glucose deprivation. However, the specific regulatory mechanism remains largely elusive. In this study, we demonstrate that glucose deprivation, while not amino acid or serum starvation, transactivates the expression of DCAF1. This enhances the K48-linked polyubiquitination and proteasome-dependent degradation of Rheb, inhibits mTORC1 activity, induces autophagy, and facilitates cancer cell survival under glucose deprivation conditions. This study identified DCAF1 as a new cellular glucose sensor and uncovered new insights into mechanism of DCAF1-mediated inactivation of Rheb-mTORC1 pathway for promoting cancer cell survival in response to glucose deprivation.
Assuntos
Sobrevivência Celular , Glucose , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteína Enriquecida em Homólogo de Ras do Encéfalo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/genética , Glucose/metabolismo , Linhagem Celular Tumoral , Autofagia , Ubiquitinação , Transdução de Sinais , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Células HEK293 , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genéticaRESUMO
Background: Hypothyroidism and hyperthyroidism are observationally associated with rheumatoid arthritis (RA), but causality is unclear. To evaluate the causal relationship between thyroid function and RA, we conducted a two-Sample bidirectional Mendelian Randomization (MR) study. Methods: Single nucleotide polymorphisms associated with six phenotypes were selected from the FinnGen biobank database, The ThyroidOmics Consortium database, and the IEU Open GWAS database. For the forward MR analysis, we selected hypothyroidism (N=213,390), Graves' disease (GD) (N=199,034), other types of hyperthyroidism (N=190,799), free thyroxine (FT4, N=49,269), and thyroid-stimulating hormone (TSH, N=54,288) as the five related thyroid function phenotypes for exposure, with RA (N=58,284) as the outcome. Reverse MR analysis selected RA as the exposure and five phenotypes of thyroid function as the outcome. The Inverse variance weighting (IVW) method was used as the primary analysis method, supplemented by weighted median (WM) and MR-Egger methods. Cochran's Q test, MR-PRESSO, MR-Egger regression methods, and leave-one-out analysis were employed to assess sensitivity and pleiotropy. Results: Forward MR evidence indicates that genetic susceptibility to hypothyroidism is associated with an increased risk of RA (ORIvw=1.758, P=7.61×10-5). Reverse MR evidence suggests that genetic susceptibility to RA is associated with an increased risk of hypothyroidism (ORIvw=1.274, P=3.88×10-20), GD (ORIvw=1.269, P=8.15×10-05), and other types of hyperthyroidism (ORIvw=1.141, P=1.80×10-03). There is no evidence to support a forward or reverse causal relationship between genetic susceptibility to RA and FT4, TSH. Conclusion: Our results provide genetic evidence supporting bidirectional causal relationships between thyroid function and RA. These findings inform preventive strategies and interventions targeting RA and thyroid dysfunction.
Assuntos
Artrite Reumatoide , Doença de Graves , Hipertireoidismo , Hipotireoidismo , Humanos , Análise da Randomização Mendeliana , Hipotireoidismo/genética , Artrite Reumatoide/genética , Predisposição Genética para Doença , TireotropinaRESUMO
AIM: The purpose of this study was to investigate the association between the metabolic score for insulin resistance (METS-IR) and bone mineral density (BMD) in American non-diabetic adults. METHODS: We conducted a cross-sectional study with 1114 non-diabetic adults from the National Health and Nutrition Examination Survey cycle (2013-2014). The associations between METS-IR and BMD of total femur and spine were assessed by the multiple linear regression and verified the non-linear relationship with a smooth curve fit and threshold effect model. Furthermore, we evaluated the relationship between METS-IR, FRAX score, and history of bone fractures. RESULTS: We found that BMD of the total femur and spine increased by 0.005 g/cm3 and 0.005 g/cm3, respectively, for a one-unit increase of METS-IR in all participants. This positive association was more pronounced among higher METS-IR participants, and there was a non-linear relationship, which was more significant when the MTTS-IRfemur was < 41.62 or the METS-IRspine was < 41.39 (ßfemur = 0.008, ßspine = 0.011, all P < 0.05). We also found that METS-IR was positively correlated with both FRAX scores in all female participants. However, METS-IR was positively correlated only with the 10-year hip fracture risk score in male participants with fractures. No significant association between METS-IR and a history of bone fractures. CONCLUSIONS: In American non-diabetic adults, there is a correlation between elevated levels of METS-IR within the lower range and increased BMD as well as decreased risk of fractures, suggesting that METS-IR holds promise as a novel biomarker for guiding osteoporosis (OP) prevention. However, it is important to carefully balance the potential benefits and risks of METS-IR in OP.
Assuntos
Fraturas do Quadril , Resistência à Insulina , Adulto , Feminino , Masculino , Humanos , Densidade Óssea , Estudos Transversais , Inquéritos NutricionaisRESUMO
Studies have demonstrated that autoantibodies to tumor-associated antigens (TAAs) may be used as efficient biomarkers with low-cost and highly sensitive characteristics. In this study, an enzyme-linked immunosorbent assay (ELISA) was conducted to analyze autoantibodies to paired box protein Pax-5 (PAX5), protein patched homolog 1 (PTCH1), and guanine nucleotide-binding protein subunit alpha-11 (GNA11) in sera from Hispanic Americans including hepatocellular carcinoma (HCC) patients, patients with liver cirrhosis (LC), patients with chronic hepatitis (CH), as well as normal controls. Meanwhile, 33 serial sera from eight HCC patients before and after diagnosis were used to explore the potential of these three autoantibodies as early biomarkers. In addition, an independent non-Hispanic cohort was used to evaluate the specificity of these three autoantibodies. In the Hispanic cohort, at the 95.0% specificity for healthy controls, 52.0%, 44.0%, and 44.0% of HCC patients showed significantly elevated levels of autoantibodies to PAX5, PTCH1, and GNA11, respectively. Among patients with LC, the frequencies for autoantibodies to PAX5, PTCH1, and GNA11 were 32.1%, 35.7%, and 25.0%, respectively. The area under the ROC curves (AUCs) of autoantibodies to PAX5, PTCH1, and GNA11 for identifying HCC from healthy controls were 0.908, 0.924, and 0.913, respectively. When these three autoantibodies were combined as a panel, the sensitivity could be improved to 68%. The prevalence of PAX5, PTCH1, and GNA11 autoantibodies has already occurred in 62.5%, 62.5%, or 75.0% of patients before clinical diagnosis, respectively. In the non-Hispanic cohort, autoantibodies to PTCH1 showed no significant difference; however, autoantibodies to PAX5, PTCH1, and GNA11 showed potential value as biomarkers for early detection of HCC in the Hispanic population and they may monitor the transition of patients with high-risk (LC, CH) to HCC. Using a panel of the three anti-TAA autoantibodies may enhance the detection of HCC.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Autoanticorpos , Receptor Patched-1 , Biomarcadores Tumorais , Cirrose Hepática , Hepatite Crônica , Hispânico ou Latino , Fator de Transcrição PAX5 , Subunidades alfa de Proteínas de Ligação ao GTPRESUMO
Esophageal squamous cell carcinoma is a severe malignancy for its high mortality and poor prognosis. Mainstay chemotherapies cause serious side effects for their ways of inducing cell death. Oridonin is the main bioactive constituent from natural plants that has anticancer ability and weak side effects. The proteomics method is efficient to understand the anticancer mechanism. However, proteins identified by proteomics aimed at understanding oridonin's anticancer mechanism is seldom overlapped by different groups. This study used proteomics based on two-dimensional electrophoresis sodium dodecyl sulfate-polyacrylamide gel electrophoresis (2-DE SDS-PAGE) integrated with mass spectrometry and Gene Set Enrichment Analysis (GSEA) to understand the anticancer mechanism of oridonin on esophageal squamous cell carcinoma (ESCC). The results showed that oridonin induced ESCC cell death via apoptosis by decreasing the protein expression of LASP1 and PDLIM1.
Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Proteínas com Domínio LIM , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Proteínas do Citoesqueleto/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Proteínas com Domínio LIM/antagonistas & inibidores , Proteínas com Domínio LIM/metabolismoRESUMO
BACKGROUND: Tumor-associated antigens (TAAs) have been investigated for many years as potential early diagnosis tools, especially for hepatocellular carcinoma (HCC). Nonetheless, very few studies have focused on the Hispanic HCC group that may be associated with distinct etiological risk factors. In the present study, we investigated novel anti-TAA autoantibodies as diagnostic biomarkers for Hispanic HCC patients. METHODS: Novel TAA targets were identified by the serological proteome analysis (SERPA) and from differentially expressed HCC driver genes via bioinformatics. The autoantibody levels were validated by enzyme-linked immunosorbent assay (ELISA). RESULTS: Among 19 potential TAA targets, 4 anti-TAA autoantibodies were investigated as potential diagnostic biomarkers with significantly high levels in Hispanic HCC sera, including DNA methyltransferase 3A (DNMT3A), p16, Hear shock protein 60 (Hsp60), and Heat shock protein A5 (HSPA5). The area under the ROC curve (AUC) value of the single autoantibodies varies from 0.7505 to 0.8885. After combining all 4 autoantibodies, the sensitivity of the autoantibody panel increased to 75% compared to the single one with the highest value of 45.8%. In a separate analysis of the Asian cohort, autoantibodies against HSPA5 and p16 showed significantly elevated levels in HCC compared to normal healthy controls, but not for DNMT3A or HSP60. CONCLUSION: Anti-DNMT3A, p16, HSPA5, and HSP60 autoantibodies have the potential to be diagnostic biomarkers for Hispanic HCC patients, of which DNMT3A and HSP60 might be exclusive for Hispanic HCC diagnosis.
Assuntos
Anticorpos Antineoplásicos , Antígenos de Neoplasias , Autoanticorpos , Biomarcadores Tumorais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Antígenos de Neoplasias/imunologia , Autoanticorpos/sangue , Biomarcadores Tumorais/imunologia , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Chaperona BiP do Retículo Endoplasmático/imunologia , Hispânico ou Latino , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/diagnóstico , Proteoma , Anticorpos Antineoplásicos/sangueRESUMO
The aim of this study was to explore the value of autoantibody to GNAS in the early detection of hepatocellular carcinoma (HCC). In a large-scale sample set of 912 participants (228 cases in each of HCC, liver cirrhosis (LC), chronic hepatitis B (CHB), and normal controls (NCs) groups), autoantibody to GNAS was detected with a positive result in 47.8% of HCC patients, which was significantly higher than that in patients with LC (35.1%), CHB (19.7%), and NCs (19.7%). Further analysis showed that the frequency of autoantibody to GNAS started increasing in compensated cirrhosis patients (37.0%) with a jump in decompensated cirrhosis patients (53.2%) and reached a peak in early HCC patients (62.4%). The increasing autoantibody response to GNAS in patients at different stages was closely associated with the progression of chronic liver lesions. The result from 44 human serial sera demonstrated that 5 of 11 (45.5%) HCC patients had elevated autoantibody to GNAS before and/or at diagnosis of HCC. Moreover, 46.1% and 62.4% of high positive rates in alpha-fetoprotein (AFP) negative and early-stage HCC patients can supplement AFP in early detection of HCC. These findings suggest that autoantibody to GNAS could be used as a potential biomarker for the early detection of HCC.
RESUMO
p62/IMP2 is an oncofetal protein that was first reported as a tumor-associated antigen in hepatocellular carcinoma (HCC). In our previous studies, we demonstrated a high frequency of p62/IMP2 autoantibodies appearing in various types of cancer. Therefore, we hypothesize that p62/IMP2 plays an important role in the progression of HCC, although the mechanism remains to be explored. In this study, we evaluated the expression of p62/IMP2 protein both in human tissues and liver cancer cell lines by immunohistochemistry and western blotting analysis and found that p62/IMP2 protein is overexpressed in human HCC tissue in comparison to normal human liver tissue. To explore the role that p62/IMP2 plays in HCC, p62/IMP2 was knocked out in two p62/IMP2-positive liver cancer cell lines (SNU449 and HepG2). Due to the low expression level of p62/IMP2 in SNU449, we overexpressed p62/IMP2 in this cell line. We subsequently demonstrated that high expression of p62/IMP2 in both cell lines can promote cell migration and invasion abilities in vitro by activating the Wnt/ß-catenin pathway. We also used the Wnt/ß-catenin pathway inhibitor, XAV 939, and a phosphoproteome assay to confirm our findings. Conclusion: Our results suggest that p62/IMP2 is an essential regulator of Wnt signaling pathways and plays an important role in HCC progression and metastasis.
RESUMO
In current study, we investigated the anti-tumor effect of luteolin in human ESCC cell lines in vitro and in vivo and tried to explore the potential mechanisms. Results from flow cytometry showed that luteolin could induce apoptosis and caspase-3 activation and induce cell cycle arrest at G2/M phase in a dose- and time-dependent manner in EC1 and KYSE450 cells. JC-1 test results showed that membrane potential of mitochondria after luteolin treatment was down-regulated and this was an indicator for intrinsic apoptosis. Western Blot results showed the expression of cell cycle regulatory protein p21 and p53 increased and three apoptosis related proteins that participate in mitochondrial apoptotic pathway, namely, Bim, CYT-c and cPARP, also increased in luteolin treated cells compared with control groups. We further confirmed that luteolin could significantly inhibit the growth of ESCC tumors in xenograft mouse models and no evidence of systemic toxicity was observed. Our results suggest that luteolin can induce cell apoptosis and cell cycle arrest in G2/M phase through mitochondrial pathway in EC1 and KYSE450 cell lines and proper utilization of luteolin might be a practical approach in ESCC chemotherapy.
Assuntos
Apoptose/efeitos dos fármacos , Luteolina/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Animais , Proteína 11 Semelhante a Bcl-2/genética , Proteína 11 Semelhante a Bcl-2/metabolismo , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Neoplasias Esofágicas , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In this paper, a novel velocimeter based on laser self-mixing Doppler technology has been developed for speed measurement. The laser employed in our experiment is a distributed feedback (DFB) fiber laser, which is an all-fiber structure using only one Fiber Bragg Grating to realize optical feedback and wavelength selection. Self-mixing interference for optical velocity sensing is experimentally investigated in this novel system, and the experimental results show that the Doppler frequency is linearly proportional to the velocity of a moving target, which agrees with the theoretical analysis commendably. In our experimental system, the velocity measurement can be achieved in the range of 3.58 mm/s-2216 mm/s with a relative error under one percent, demonstrating that our novel all-fiber configuration velocimeter can implement wide-range velocity measurements with high accuracy.
RESUMO
PURPOSE: Targeting the protein neddylation pathway has become an attractive anticancer strategy; however, the role of death receptor-mediated extrinsic apoptosis during treatment remained to be determined. EXPERIMENTAL DESIGN: The activation of extrinsic apoptosis and its role in MLN4924 treatment of human esophageal squamous cell carcinoma (ESCC) were evaluated both in vitro and in vivo The expression of the components of extrinsic apoptotic pathway was determined by immunoblotting analysis and downregulated by siRNA silencing for mechanistic studies. RESULTS: Pharmaceutical or genetic inactivation of neddylation pathway induced death receptor 5 (DR5)-mediated apoptosis and led to the suppression of ESCC in murine models. Mechanistically, neddylation inhibition stabilized activating transcription factor 4 (ATF4), a Cullin-Ring E3 ubiquitin ligases (CRL) substrate. Transcription factor CHOP was subsequently transactivated by ATF4 and further induced the expression of DR5 to activate caspase-8 and induce extrinsic apoptosis. Moreover, the entire neddylation pathway was hyperactivated in ESCC and was negatively associated with patient overall survival. CONCLUSIONS: Our findings highlight a critical role of ATF4-CHOP-DR5 axis-mediated extrinsic apoptosis in neddylation-targeted cancer therapy and support the clinical investigation of neddylation inhibitors (e.g., MLN4924) for the treatment of ESCC, a currently treatment-resistant disease with neddylation hyperactivation. Clin Cancer Res; 22(16); 4145-57. ©2016 AACR.
Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Apoptose , Neoplasias Esofágicas/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Transdução de Sinais , Fator de Transcrição CHOP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Biomarcadores , Caspase 8/metabolismo , Linhagem Celular Tumoral , Ciclopentanos/farmacologia , Modelos Animais de Doenças , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Inativação Gênica , Humanos , Camundongos , Modelos Biológicos , Prognóstico , Pirimidinas/farmacologia , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND/AIMS: Esophageal squamous cell carcinoma (ESCC) is a recalcitrant cancer. Mouse models of this disease could be used for discovery of more effective therapy for ESCC. MATERIALS AND METHODS: The green fluorescent protein (GFP)-expressing human esophageal cancer EC1 cell line was established with a lentiviral expression system. Subsequently, nude mice were injected subcutaneously, intracardiac or intravenously, or orthotopically implanted with EC1-GFP cells. Tumor growth and metastasis were examined by fluorescence in vivo imaging or by open fluorescence imaging after autopsy. RESULTS: Four different mouse xenograft models of ESCC expressing GFP were established. In the subcutaneous model, primary tumor growth was monitored in real-time by whole-body fluorescence imaging. No metastasis was observed in the subcutaneous or surgical orthotopic implantation model. By 55 days after implantation, all mice had developed orthotopic esophageal cancer, but without detectable metastasis. In contrast, experimental metastasis occurred in the intracardiac and intravenous models. In the intravenous injection model, the lung was the sole organ of experimental metastasis. In the intracardiac model, extensive experimental metastases occurred in the bone, brain and lung. CONCLUSION: The mouse xenograft models of ESCC developed in the present study can provide a means of discovering more effective therapy of this recalcitrant type of cancer.