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1.
Mol Med ; 30(1): 9, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216914

RESUMO

BACKGROUND: Lysine demethylase 5C (KDM5C) has been implicated in the development of several human cancers. This study aims to investigate the role of KDM5C in the progression of colorectal cancer (CRC) and explore the associated molecular mechanism. METHODS: Bioinformatics tools were employed to predict the target genes of KDM5C in CRC. The expression levels of KDM5C and prefoldin subunit 5 (PFDN5) in CRC cells were determined by RT-qPCR and western blot assays. The interaction between KDM5C, H3K4me3, and PFDN5 was validated by chromatin immunoprecipitation. Expression and prognostic values of KDM5C and PFDN5 in CRC were analyzed in a cohort of 72 patients. The function of KDM5C/PFDN5 in c-Myc signal transduction was analyzed by luciferase assay. Silencing of KDM5C and PFDN5 was induced in CRC cell lines to analyze the cell malignant phenotype in vitro and tumorigenic activity in nude mice. RESULTS: KDM5C exhibited high expression, while PFDN5 displayed low expression in CRC cells and clinical CRC samples. High KDM5C levels correlated with poor survival and unfavorable clinical presentation, whereas elevated PFDN5 correlated with improved patient outcomes. KDM5C mediated demethylation of H3K4me3 on the PFDN5 promoter, suppressing its transcription and thereby enhancing the transcriptional activity of c-Myc. KDM5C knockdown in CRC cells suppressed cell proliferation, migration and invasion, epithelial-mesenchymal transition, and tumorigenic activity while increasing autophagy and apoptosis rates. However, the malignant behavior of cells was restored by the further silencing of PFDN5. CONCLUSION: This study demonstrates that KDM5C inhibits PFDN5 transcription, thereby activating c-Myc signal transduction and promoting CRC progression.


Assuntos
Neoplasias Colorretais , Lisina , Chaperonas Moleculares , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Lisina/genética , Lisina/metabolismo , Camundongos Nus , Processos Neoplásicos , Transdução de Sinais
2.
Clin Exp Pharmacol Physiol ; 50(7): 561-572, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36946190

RESUMO

Aerobic glycolysis is critical for the energy metabolism of cancer cells. This study focuses on the regulation of forkhead box A2 (FOXA2) on pyruvate kinase M2 (PKM2) and their effects on the glycolytic activity and malignant phenotype of thyroid carcinoma (THCA) cells. By analysing four Gene Expression Omnibus datasets and querying bioinformatics systems, we obtained FOXA2 as a poorly expressed transcription factor in THCA. Later, we validated decreased mRNA and protein levels of FOXA2 in THCA cells by quantitative polymerase chain reaction and western blot assays. FOXA2 upregulation in THCA cells suppressed the glucose uptake and lactate production, and it reduced the extracellular acidification rate, but increased the oxygen consumption rate of cells. Meanwhile, the FOXA2 overexpression blocked the proliferation and mobility, and the tumourigenic activity of cancer cells. The chromatin immunoprecipitation and luciferase assays showed that FOXA2 bound to PKM2 promoter and suppressed the transcription of PKM2, which was highly expressed in THCA cells. Further upregulation of PKM2 elevated the ß-catenin, c-Myc and cyclin D1 levels and restored the glycolytic activity as well as the malignant properties of cancer cells. Collectively, this work reveals that FOXA2 suppresses aerobic glycolysis and progression of THCA by blocking PKM2 transcription and inactivating the Wnt/ß-catenin pathway.


Assuntos
Neoplasias da Glândula Tireoide , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Via de Sinalização Wnt/genética , Regulação para Cima , Neoplasias da Glândula Tireoide/genética , Glicólise/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Fator 3-beta Nuclear de Hepatócito/genética , Fator 3-beta Nuclear de Hepatócito/metabolismo
3.
Appl Biochem Biotechnol ; 195(10): 6050-6067, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36418715

RESUMO

Drug resistance is a major obstacle leading to treating failure and poor outcome in gastric cancer (GC). This study explores the interaction between SMAD family member 1 (SMAD1) and Yes1-associated transcriptional regulator (YAP1) and their roles in cisplatin (DDP) resistance in GC. Transcriptome analysis predicted that SMAD1 is highly expressed in DDP-resistant cells. Elevated SMAD1 expression was detected in GC tissue and cells, especially in DDP-resistant cells (MKN-45/DDP and AGS/DDP). SMAD1 downregulation in cells decreased 50% inhibition value of DDP, reduced proliferation, migration, and invasion, and promoted cell cycle arrest and apoptosis. A protein-protein interaction network suggested a possible SMAD1 and YAP1 interaction in GC. The SMAD1 and YAP1 interaction was validated by chromatin immunoprecipitation (ChIP), co-immunoprecipitation (Co-IP), and luciferase assays. SMAD1 bound to YAP1 and activated its transcription. SMAD1 formed complexes with YAP1 in nucleus, and YAP1 upregulation enhanced SMAD1 activity as well. Upregulation of YAP1 restored the malignant behaviors of GC cells suppressed by SMAD1 silencing. In vivo, SMAD1 silencing suppressed growth and DDP resistance of xenograft tumors in nude mice, and this suppression was blocked by YAP1 overexpression again. In conclusion, this study demonstrates that SMAD1 can interact with YAP1 to enhance the DDP resistance of GC cells.


Assuntos
MicroRNAs , Neoplasias Gástricas , Animais , Camundongos , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias Gástricas/metabolismo , Camundongos Nus , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Proliferação de Células , MicroRNAs/metabolismo
4.
Front Oncol ; 12: 1021453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36457490

RESUMO

Objectives: To investigate the short-term efficacy and radiotoxicity 3.543of chronoradiotherapy in patients with cervical cancer. We also examined the overall symptom score and quality of life (QOL) of patients who underwent morning radiotherapy and evening radiotherapy. Methods: We conducted a multicenter randomized controlled trial to compare the effects of morning radiotherapy (9:00-11:00 AM) with evening radiotherapy (7:00-9:00 PM) in cervical cancer patients receiving radiotherapy. From November 2021 to June 2022, 114 cervical cancer patients admitted to eight cancer center hospitals in Tianjin, Chongqing, Hubei, Shanxi, Shandong, Shaanxi, Hebei, and Cangzhou were randomly divided into the morning radiotherapy group (MG; N = 61) and the evening radiotherapy group (EG; N = 53). The short-term efficacy of radiotherapy on cervical cancer patients at different time points and the occurrence of radiotoxicity were explored after patients had undergone radiotherapy. Results: The total effective response (partial remission [PR] + complete remission [CR]) rate was similar across the two groups (93.5% vs. 96.3%, p > 0.05). However, the incidence of bone marrow suppression and intestinal reaction in the two groups were significantly different (p < 0.05). The patients in the MG had significantly higher Anderson symptom scores than patients in the EG (21.64 ± 7.916 vs. 18.53 ± 4.098, p < 0.05). In terms of physical activity, functional status, and overall QOL, the MG had significantly lower scores than the EG (p < 0.05). No other measures showed a significant difference between the groups. Conclusion: The radiotherapy effect of the MG was consistent with that of the EG. The incidence of radiation enteritis and radiation diarrhea in the MG was significantly higher than that in the EG; however, bone marrow suppression and blood toxicity in the EG were more serious than in the MG. Because of the small sample size of the study, we only examined the short-term efficacy of radiotherapy. Therefore, further clinical trials are needed to verify the efficacy and side effects of chronoradiotherapy. Clinical Trial Registration: http://www.chictr.org.cn/searchproj.aspx, Registration Number: ChiCTR2100047140.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36193123

RESUMO

Purpose: To assess the association between intestinal venous blood (IVB) circulating tumor cells (CTCs) and clinicopathological parameters in stage I-III colorectal cancer (CRC) patients. Methods: Participants were retrospectively retrieved, who were admitted to our hospital or took annual physical exams between December 1, 2015 and December 31, 2018. A negative enrichment-immunofluorescence in situ hybridization (NE-imFISH) technique was used to isolate and identify CTCs. Receiver operating characteristic (ROC) curves and Youden index values were used to determine the critical CTC cutoff value for the diagnosis of CRC. Kaplan-Meier and log-rank methods were used to conduct survival analyses, and multivariate Cox regression analyses were employed for multivariate corrections to comprehensively evaluate the value of CTCs in the diagnosis of CRC. Relationships between IVB CTCs, clinicopathological parameters, and prognosis were then analyzed based upon patient postoperative follow-up data. Results: In total, we retrieved 282 patients including 48 healthy controls, 72 patients with benign colorectal tumors, and 162 CRC patients. CRC patients exhibited significantly higher numbers of CTCs relative to control patients or those with benign disease. CTC numbers in CRC patient peripheral blood (PB) and IVB were closely associated with tumor node metastasis (TNM) staging (P < 0.01), carbohydrate antigen-125 (CA-125) levels (P < 0.001), and KRAS (Kirsten rat sarcoma virus oncogene) mutation status (P < 0.001). The disease-free survival (DFS) of patients in the CTC-negative group was significantly longer than that of patients in the CTC-positive group (24.60 ± 13.31 months vs. 18.70 ± 10.19 months, P < 0.05), with the same being true with respect to their overall survival (OS) (30.60 ± 12.44 months vs. 35.25 ± 11.57 months, P < 0.05). A multivariate analysis revealed that the detection ≥2 CTCs/3.2 ml was independently associated with poorer DFS and OS. CTC counts were independently predictive of CRC patients TNM staging, CA-125, and KRAS mutation status in both univariate and multivariate Cox proportional hazards regression analyses. Conclusion: CTCs are valuable biomarkers that can be monitored to predict CRC patient disease progression.

6.
Biochim Biophys Acta Mol Basis Dis ; 1868(11): 166487, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35840042

RESUMO

Clinically, hypoxia is a major risk factor for long QT syndrome (LQTS), which is associated with many diseases, such as myocardial ischemia. LQTS can be caused by the deficiency of hERG, a potassium ion channel that plays a key role in cardiac repolarization. Modifications such as acetylation of histones or non-histone proteins can affect the protein expression. In the present study, we explored the mechanism underlying hypoxia-induced LQTS and a potential reversal strategy. Experiments were performed under hypoxia to determine transcriptional and post-transcriptional expression changes. We used real-time PCR, chromatin immunoprecipitation assay, and western blotting to determine the histones acetylation in the hERG gene and the mechanism. Molecular docking, western blotting, IP, and patch -clamp assay were performed to determine the acetylation and ubiquitination levels of hERG protein and the mechanism. hERG mRNA and protein expression were found to decrease under hypoxia. The histone deacetylation level increased under hypoxia at both H3K27 and H4 of the hERG gene. HDAC1 and HDAC2 are the key enzymes for the mechanism. HDAC6 directly interacts with hERG. The acetylation level of hERG decreased and the ubiquitination level of hERG increased under hypoxia. The inhibitors of HDAC1, HDAC2, and HDAC6 could reverse the reduction of hERG mRNA and hERG protein expression under hypoxia. In conclusion, deacetylation of hERG gene-associated histones and hERG protein might be the mechanisms for LQTS in patients with hypoxia, and the inhibition of HDAC1, HDAC2, and HDAC6 might be a promising reversal strategy for reducing hERG expression under different pathological conditions.


Assuntos
Canais de Potássio Éter-A-Go-Go , Síndrome do QT Longo , Canais de Potássio Éter-A-Go-Go/genética , Canais de Potássio Éter-A-Go-Go/metabolismo , Humanos , Hipóxia , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/genética , Simulação de Acoplamento Molecular , RNA Mensageiro
7.
Anal Cell Pathol (Amst) ; 2022: 5374262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242497

RESUMO

The association between collagen type I alpha (COL1A) and chemoresistance has been verified in cancers. However, the specific role of COL1A2 in gastric cancer (GC) cell resistance to apatinib, a highly selective small-molecule inhibitor of vascular endothelial growth factor receptor 2, has not been investigated before. The purpose of this study was to explore the potential factors associated with COL1A2 regulation on GC cell apatinib resistance in vitro. With the aid of the Oncomine database and integrated bioinformatics methods, we identified COL1A2 overexpression in GC and its prognostic value. Mechanistically, the COL1A2 promoter has a distinct H3K27ac modification site and that E1A binding protein p300 (EP300) and twist family bHLH transcription factor 1 (TWIST1) can bind to the COL1A2 promoter, which in turn transcriptionally activated COL1A2 expression. In addition, overexpression of COL1A2 significantly promoted resistance to apatinib in GC cells, but knockdown of EP300 or TWIST1 remarkably inhibited COL1A2 expression and promoted sensitivity of GC cells to apatinib. Our findings demonstrated that the combination of EP300 and TWIST1 has a synergistically regulatory effect on COL1A2 expression, thus contributing to apatinib resistance in GC cells.


Assuntos
Neoplasias Gástricas , Linhagem Celular Tumoral , Colágeno Tipo I/genética , Proteína p300 Associada a E1A/genética , Humanos , Proteínas Nucleares , Piridinas , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Proteína 1 Relacionada a Twist/genética , Fator A de Crescimento do Endotélio Vascular
8.
Dig Dis Sci ; 67(6): 2195-2208, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33982216

RESUMO

BACKGROUND: Mucin 16 (MUC16), a cell surface-associated mucin, has been implicated to be upregulated in a large repertoire of malignances. However, its function in the pathogenesis of colorectal cancer (CRC) is unknown. AIMS: Here, we explored the regulatory role of MUC16 in CRC. METHODS: First, tumor and paracancerous tissues, and serum samples from 162 CRC patients, peripheral blood samples from 48 healthy volunteers and 72 benign colorectal patients were collected. The correlation between the MUC16 expression and the clinical phenotypes of the patients was analyzed. Subsequently, HCT116 and SW480 cells with deletion of MUC16 were established to detect changes in the growth and metastatic capacities of CRC cells. The genes with the highest correlation with MUC16 were predicted by bioinformatics, and their binding relationships were detected by Co-IP and double-labeled immunofluorescence, followed by functional rescue experiments. RESULTS: Overexpression of MUC16 in CRC patients was positively correlated with serum biomarkers and poor prognosis of patients. It was demonstrated by in vitro and in vivo experiments that knocking-down the expression of MUC16 could significantly inhibit the growth and metastasis of CRC cells. MUC16 activated janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) by interacting with JAK2. Further overexpression of JAK2 in cells with poor expression of MUC16 revealed a significant increase in the proliferative and metastatic capacities of CRC cells. CONCLUSIONS: MUC16 contributes to the development and progression of CRC by binding to JAK2, thereby promoting phosphorylation of JAK2 and further activating STAT3 phosphorylation.


Assuntos
Antígeno Ca-125 , Neoplasias Colorretais , Janus Quinase 2 , Antígeno Ca-125/genética , Antígeno Ca-125/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Proteínas de Membrana , Fosforilação , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
9.
Mol Plant ; 14(3): 456-469, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33307246

RESUMO

Rice grain oil is a valuable nutrient source. However, the genetic basis of oil biosynthesis in rice grains remains unclear. In this study, we performed a genome-wide association study on oil composition and oil concentration in a diverse panel of 533 cultivated rice accessions. High variation for 11 oil-related traits was observed, and the oil composition of rice grains showed differentiation among the subpopulations. We identified 46 loci that are significantly associated with grain oil concentration or composition, 16 of which were detected in three recombinant inbred line populations. Twenty-six candidate genes encoding enzymes involved in oil metabolism were identified from these 46 loci, four of which (PAL6, LIN6, MYR2, and ARA6) were found to contribute to natural variation in oil composition and to show differentiation among the subpopulations. Interestingly, population genetic analyses revealed that specific haplotypes of PAL6 and LIN6 have been selected in japonica rice. Based on these results, we propose a possible oil biosynthetic pathway in rice grains. Collectively, our results provide new insights into the genetic basis of oil biosynthesis in rice grains and can facilitate marker-based breeding of rice varieties with enhanced oil and grain quality.


Assuntos
Oryza/genética , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Grão Comestível/metabolismo , Estudo de Associação Genômica Ampla/métodos
10.
Med Sci Monit ; 26: e925772, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33219199

RESUMO

BACKGROUND Increasing evidence suggests that the alternative splicing (AS) signature plays a role in the carcinogenesis and prognosis of various cancers. However, the prognostic role of AS in gastric cancer is not clear and needs to be clarified. MATERIAL AND METHODS To identify the differentially expressed AS (DEAS) events, we performed a differential expression analysis between normal and tumor tissue. The DEAS event was further applied to construct a prognostic signature by performing univariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) analysis. The Kaplan-Meier curve analysis and receiver operating characteristic curve (ROC) analysis were used to evaluate the prognostic value of the AS signature. In addition, the network of the splicing events with splicing factors was constructed using the Cytoscape software. RESULTS A total of 30 005 alternative splicing (AS) events with 372 patients were retrieved from the SpliceSeq database and TCGA database. By performing differential expression analysis, a total of 419 alternative splicing events were screened out, including 56 upregulated and 363 downregulated. We further constructed an AS-related prognostic signature by conducting a series bioinformatics analyses. Moreover, we identified that the AS signature could serve as an independent predictor for the prognosis of GC. We also found that AS signature had a more robust and precise efficacy for prognostic prediction in GC patients. Interestingly, the areas under 3- and 5-year survival curves are similar, both of which are greater than 1-year survival curve, suggesting that the long-term predictive accuracy of our prognostic model built upon AS signature is superior. CONCLUSIONS We performed a comprehensive analysis of overall prognostic-associated AS events concerning GC and constructed a prognostic model to predict the long-term prognostic survival outcomes in GC patients. We also developed a network of splicing events with splicing factors to reveal new potential molecular diagnostic biomarkers and therapeutic targets for GC patients.


Assuntos
Processamento Alternativo/genética , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Neoplasias Gástricas/genética , Estudos de Coortes , Redes Reguladoras de Genes , Humanos , Prognóstico , Modelos de Riscos Proporcionais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC , Análise de Sobrevida
11.
Curr Med Sci ; 40(3): 434-443, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32681248

RESUMO

Progressive memory loss and cognitive impairment are the main clinical manifestations of Alzheimer's disease (AD). Currently, there is no effective drug available for the treatment of AD. Previous studies have demonstrated that the cognitive impairment of AD is associated with oxidative stress and the inhibition of AKT and ERK phosphorylation. Grape seed proanthocyanidin extract (GSPE) has been shown to have strong antioxidant effect and can protect the nervous system from oxidative stress damage. This study aimed to investigate the protective effect of GSPE on the cognitive and synaptic impairments of AD using a sporadic AD rat model induced by intracerebroventricular (ICV) injection of streptozotocin (STZ) (ICV-STZ). Rats were treated with GSPE (50, 100, or 200 mg/kg every day) by intragastrical (ig.) administration for continuous 7 weeks, and ICV-STZ (3 mg/kg) was performed on the first day and third day of week 5. Learning and memory abilities were assessed by the Morris water maze (MWM) test at week 8. After behavioral test, hippocampal long-term potentiation (LTP) was recorded, and the levels of malondialdehyde (MDA), superoxide dismutases (SOD), glutathione (GSH) and the protein expression of AKT and ERK were measured in the hippocampus and cerebral cortex of rats. Our study revealed that ICV-STZ significantly impaired the working learning ability and hippocampal LTP of rats, significantly increased the levels of MDA, and decreased the activity of SOD and GSH in the hippocampus and cerebral cortex. In contrast, GSPE treatment prevented the impairment of cognitive function and hippocampal LTP induced by ICV-STZ, decreased the level of MDA, and increased the level of SOD and GSH. Furthermore, Western blot results showed that GSPE treatment could prevent the loss of AKT and ERK activities in the hippocampus and cerebral cortex induced by ICV-STZ. Our findings demonstrate that GSPE treatment could ameliorate the impairment of cognitive ability and hippocampal synaptic plasticity in a rat model of sporadic AD by inhibiting oxidative stress and preserving AKT and ERK activities. Therefore, GSPE may be an effective agent for the treatment of cognitive deficits associated with sporadic AD.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Extrato de Sementes de Uva/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proantocianidinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estreptozocina/farmacologia , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Antioxidantes/fisiologia , Cognição/efeitos dos fármacos , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Glutationa/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
12.
Nat Commun ; 11(1): 1580, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221286

RESUMO

ADAR RNA editing enzymes are high-affinity dsRNA-binding proteins that deaminate adenosines to inosines in pre-mRNA hairpins and also exert editing-independent effects. We generated a Drosophila AdarE374A mutant strain encoding a catalytically inactive Adar with CRISPR/Cas9. We demonstrate that Adar adenosine deamination activity is necessary for normal locomotion and prevents age-dependent neurodegeneration. The catalytically inactive protein, when expressed at a higher than physiological level, can rescue neurodegeneration in Adar mutants, suggesting also editing-independent effects. Furthermore, loss of Adar RNA editing activity leads to innate immune induction, indicating that Drosophila Adar, despite being the homolog of mammalian ADAR2, also has functions similar to mammalian ADAR1. The innate immune induction in fly Adar mutants is suppressed by silencing of Dicer-2, which has a RNA helicase domain similar to MDA5 that senses unedited dsRNAs in mammalian Adar1 mutants. Our work demonstrates that the single Adar enzyme in Drosophila unexpectedly has dual functions.


Assuntos
Adenosina Desaminase/genética , Encéfalo/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/imunologia , Imunidade Inata/genética , Edição de RNA/genética , Adenosina Desaminase/química , Monofosfato de Adenosina/metabolismo , Envelhecimento/patologia , Animais , Catálise , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica , Locomoção , Degeneração Neural/patologia , Mutação Puntual/genética , Domínios Proteicos , RNA Helicases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribonuclease III/metabolismo
13.
Plant J ; 102(3): 517-528, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31830332

RESUMO

Grain size is a major determinant of grain weight, a key component of grain yield of rice. Here, we identified the grain size gene WIDE GRAIN 7 (WG7) from a T-DNA insertion mutant. The grain size of WG7 knockout mutants and WG7 overexpression lines indicated that WG7 is a positive regulator of grain size. WG7 encodes a cysteine-tryptophan (CW) domain-containing transcriptional activator. EMSAs and ChIP-qPCR assay confirmed that WG7 directly bound to the promoter of OsMADS1, a grain size gene, and thereby significantly activated its expression. Point mutations showed that the cis-element CATTTC motif in the promoter was the binding site of WG7. Compared with the wild-type, deletion mutants of the cis-element motif exhibited lower expression of OsMADS1 and produced narrower grains, implicating the requirement of this motif for WG7 function. ChIP-qPCR assays showed that WG7 enhanced histone H3K4me3 enrichment in the promoter of OsMADS1. WG7 underwent directional selection due to the poor fertility of the non-functional mutant. These findings demonstrated that WG7 upregulated OsMADS1 expression by directly binding to its promoter, enhanced histone H3K4me3 enrichment in the promoter and ultimately increased grain width. This study will enrich the knowledge concerning the regulatory network of grain size formation in rice.


Assuntos
Oryza/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Sítios de Ligação/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética
14.
Genome Biol Evol ; 11(4): 1207-1222, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30918938

RESUMO

RNA virus high mutation rate is a double-edged sword. At the one side, most mutations jeopardize proteins functions; at the other side, mutations are needed to fuel adaptation. The relevant question then is the ratio between beneficial and deleterious mutations. To evaluate this ratio, we created a mutant library of the 6K2 gene of tobacco etch potyvirus that contains every possible single-nucleotide substitution. 6K2 protein anchors the virus replication complex to the network of endoplasmic reticulum membranes. The library was inoculated into the natural host Nicotiana tabacum, allowing competition among all these mutants and selection of those that are potentially viable. We identified 11 nonsynonymous mutations that remain in the viral population at measurable frequencies and evaluated their fitness. Some had fitness values higher than the wild-type and some were deleterious. The effect of these mutations in the structure, transmembrane properties, and function of 6K2 was evaluated in silico. In parallel, the effect of these mutations in infectivity, virus accumulation, symptoms development, and subcellular localization was evaluated in the natural host. The α-helix H1 in the N-terminal part of 6K2 turned out to be under purifying selection, while most observed mutations affect the link between transmembrane α-helices H2 and H3, fusing them into a longer helix and increasing its rigidity. In general, these changes are associated with higher within-host fitness and development of milder or no symptoms. This finding suggests that in nature selection upon 6K2 may result from a tradeoff between within-host accumulation and severity of symptoms.


Assuntos
Evolução Molecular , Mutação , Potyvirus/genética , Proteínas Virais/genética , Replicação Viral , Fenótipo
15.
Oncol Lett ; 14(2): 1309-1314, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28808482

RESUMO

Prunella vulgaris (PV), a traditional Chinese herb, has been shown to be rich in bioactive chemicals and possess anti-proliferative and pro-apoptotic effects on tumor cells. The effect of PV on human well-differentiated thyroid carcinoma (WDTC), which accounts for the majority of common endocrine malignancies, remains to be elucidated. The present study aimed to investigate the function of PV on WDTC cell lines and apoptosis-associated signaling pathway activity. Additional studies demonstrated that PV may induce apoptosis in WDTC TPC-1 and FTC-133 cell lines, using the Cell Counting Kit-8 assay. Morphological changes of apoptotic cells were observed by Hoechst 33342 and acridine orange/ethidium bromide staining. In addition, ladder pattern of fragmented DNA was observed by DNA gel electrophoresis. It was also observed that PV significantly increased Bcl-2-associated X protein and caspase-3 expression, and downregulated B-cell lymphoma-2 expression in TPC-1 and FTC-133 by reverse transcription-quantitative polymerase chain reaction (P<0.05). Thus, the present results indicated that PV has the potential to be a future WDTC therapeutic agent.

16.
Medicine (Baltimore) ; 95(52): e5794, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28033304

RESUMO

BACKGROUND: It is widely accepted that maximal extrathyroidal extension (ETE) plays a vital role in the prognosis of papillary thyroid carcinoma (PTC). However, there is no consensus among researchers about the meaning of minimal ETE (mETE) in PTC. Herein, we conducted a systematic review and meta-analysis to examine the role of mETE in the prognosis of PTC. METHODS: We searched PubMed, EMBASE, and Cochrane search trials databases in English to identify studies comparing data on disease recurrence in PTC patients with mETE and those with no ETE. To summarize the data related to mETE status, risk ratios and hazard ratios adjusted for potential confounders were used to assess the number of recurrence and time-dependent risks related to mETE status, respectively. RESULTS: According to the inclusion criteria, a total of 7951 patients from 9 studies were included. The recurrence rate in patients with mETE is significantly higher when compared with those with no ETE (risk ratio = 1.70, 95% confidence interval: 1.26-2.28, I = 56%). According to the data summarized with hazard ratios, PTC patients with mETE showed a significantly increased risk of disease recurrence. CONCLUSION: mETE is a risk factor for poor prognosis in patients with PTC. Our innovative classification of ETE has its value in assessing the prognosis of PTC.


Assuntos
Carcinoma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Glândula Tireoide/patologia , Carcinoma Papilar , Intervalo Livre de Doença , Humanos , Fatores de Risco , Câncer Papilífero da Tireoide
17.
Clin Endocrinol (Oxf) ; 85(2): 299-305, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26732020

RESUMO

BACKGROUND: The prognostic value of the telomerase reverse transcriptase (TERT) promoter mutation, resulting in poor clinical outcomes of papillary thyroid carcinoma (PTC), has been generally confirmed. To data, there is no high-level evidence approving the association of TERT promoter mutation and aggressive clinical behaviours in PTC. To systematically evaluate it, a systematic review and meta-analysis of the published literatures were carried out. METHODS: We conducted a systematic search in PubMed, EMBASE, OVID and Web of Science databases for relevant studies. We selected all the studies that reported clinicopathological features of PTC patients with information available on TERT promoter mutation status. Individual study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, as were Mantel-Haenszel pooled odds ratios for the combined studies. RESULTS: Eight eligible trials involved 2035 patients were included in the analysis. The average prevalence of the TERT promoter mutation was 10·32%. Compared with the wild-type TERT promoter gene, the TERT promoter mutation was associated with male gender, lymph node metastasis, extrathyroidal extension, distant metastasis, advanced TNM stage III/IV, poor clinical outcome (persistence or recurrence) and mortality. The associations were generally consistent across the different study populations. CONCLUSIONS: Thus, our findings from this large meta-analysis definitively demonstrate that TERT promoter mutation-positive PTC is more likely to manifest with aggressive clinicopathological characteristics. In appropriate clinical settings, testing for the TERT promoter mutation is likely to be useful in assisting the risk stratification and management of PTC.


Assuntos
Carcinoma/genética , Telomerase/genética , Neoplasias da Glândula Tireoide/genética , Carcinoma/diagnóstico , Carcinoma Papilar , Humanos , Mutação , Prognóstico , Regiões Promotoras Genéticas , Medição de Risco , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/diagnóstico
18.
Plant Cell ; 27(9): 2455-68, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26296966

RESUMO

The photoperiodic response is one of the most important factors determining heading date in rice (Oryza sativa). Although rhythmic expression patterns of flowering time genes have been reported to fine-tune the photoperiodic response, posttranslational regulation of key flowering regulators has seldom been elucidated in rice. Heading date 1 (Hd1) encodes a zinc finger transcription factor that plays a crucial role in the photoperiodic response, which determines rice regional adaptability. However, little is known about the molecular mechanisms of Hd1 accumulation during the photoperiod response. Here, we identify a C3HC4 RING domain-containing E3 ubiquitin ligase, Heading date Associated Factor 1 (HAF1), which physically interacts with Hd1. HAF1 mediates ubiquitination and targets Hd1 for degradation via the 26S proteasome-dependent pathway. The haf1 mutant exhibits a later flowering heading date under both short-day and long-day conditions. In addition, the haf1 hd1 double mutant headed as late as hd1 plants under short-day conditions but exhibited a heading date similar to haf1 under long-day conditions, thus indicating that HAF1 may determine heading date mainly through Hd1 under short-day conditions. Moreover, high levels of Hd1 accumulate in haf1. Our results suggest that HAF1 is essential to precise modulation of the timing of Hd1 accumulation during the photoperiod response in rice.


Assuntos
Flores/fisiologia , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Sequência de Aminoácidos , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Mutação , Fotoperíodo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae/genética , Nicotiana/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Dedos de Zinco
19.
Int J Clin Exp Pathol ; 8(5): 5371-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26191239

RESUMO

This study was to investigate the effects of intracerebral hemorrhage (ICH) and subsequent minimally invasive hematoma aspiration on the expression of apoptosis-related genes in rats. IV-collagenase was injected to the caudate nucleus of the rats to make ICH models. In the control group, 30 Sprague-Dawley (SD) rats were mock treated with saline instead of collagenase. Thirty SD rats with successful modeling were designated as the ICH group. Twenty-five SD rats with successful modeling and subsequent minimally invasive hematoma aspiration were designated as the therapy group. Expression of heat shock protein 70 (Hsp70), B-cell leukemia/lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) in the brain tissues was detected by immunohistochemical assays. The expression of Hsp70, Bcl-2 and Bax in the control group was very low, and significantly increased in the ICH group and the therapy group. At each indicated time point, Hsp70 expression in the therapy group was significantly lower than that of the ICH group, Bax expression in the therapy group was significantly lower than that of the ICH group and Bcl-2 expression in the therapy group was significantly higher than that of the ICH group. These results suggest that ICH led to increased expression of apoptosis-related genes in the brain tissues. Hematoma aspiration up-regulated ICH induced Bcl-2 expression while down-regulated ICH induced Hsp70 and Bax expression.


Assuntos
Apoptose , Encéfalo/metabolismo , Hemorragia Cerebral/terapia , Hematoma/terapia , Sucção , Animais , Apoptose/genética , Encéfalo/patologia , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/genética , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patologia , Colagenases , Modelos Animais de Doenças , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/metabolismo , Hematoma/induzido quimicamente , Hematoma/genética , Hematoma/metabolismo , Hematoma/patologia , Imuno-Histoquímica , Cinética , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Proteína X Associada a bcl-2/metabolismo
20.
Inflammation ; 38(4): 1617-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25687641

RESUMO

Inflammatory response plays an important role in the pathogenesis of ischemic stroke and anti-inflammatory agents may provide a choice of treatment. Triptolide is reported to be anti-inflammatory. In this study, we investigated the effects of triptolide on cultured neuronal cell line in vitro and experimental ischemic stroke in vivo. Oxygen-glucose deprivation (OGD) and tumor necrosis factor-α (TNF-α) stimulated SH-SY5Y cells were incubated with triptolide. In vivo, rats were subjected to middle cerebral artery occlusion (MCAO) for 1 h, followed by reperfusion for 23 h. Results of this study showed that triptolide treatment reduced the OGD-induced cytotoxicity and apoptosis and blocked TNF-α-induced activation of NF-κB and p38MAPK in SH-SY5Y cells. Intraperitoneal injection of triptolide showed significant neuroprotective actions in stroke rats. Triptolide attenuated neurological deficit, brain infarct volume, and brain water content, and inhibited activation of NF-κB and p38MAPK. These data show that triptolide protects rats against ischemic cerebral injury via inhibiting NF-κB and p38MAPK signaling pathways.


Assuntos
Isquemia Encefálica/prevenção & controle , Diterpenos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Fenantrenos/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Animais , Isquemia Encefálica/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Humanos , Masculino , Fármacos Neuroprotetores/farmacologia , Fenantrenos/farmacologia , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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