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1.
J Environ Manage ; 344: 118401, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37364487

RESUMO

As the requirements for environmental protection and high-efficiency economies increase, grain production (GP) across the globe faces more stringent ecological constraints and economic pressure. Understanding the relationships between natural resources and economic and agricultural factors in grain-producing regions is paramount for ensuring global food security. This paper proposes a methodological framework to explore the relationships between water and soil resources (WSRs), economic input factors (EIFs), and GP. We employed the northeast region of China as a case study to advance our understanding of the factors driving the development of grain-producing capacity. We first constructed and calculated the region's water and soil comprehensive index (WSCI) to describe water-soil properties. We then used hotspot analysis to explore the spatial agglomeration characteristics of WSRs, EIFs, and GP. Finally, we used threshold regression analysis to understand the effects of EIFs and GP with the WSCI as the threshold variable. With the improvement of the WSCI, the positive impact of fertilizer and irrigation on GP shows a U-shaped curve in elasticity coefficients. The positive effect of agricultural machinery on GP decreases significantly, and the impact of labor input on GP is insignificant. These results provide new insights into the relationship between WSRs, EIFs, and GP and a reference for improving GP efficiency globally. This work thus contributes to advancing our capabilities to enable food security while considering aspects of sustainable agriculture in important grain-producing regions across the globe.


Assuntos
Solo , Água , Agricultura , Grão Comestível , Conservação dos Recursos Naturais/métodos , China , Recursos Hídricos
2.
Anticancer Res ; 43(4): 1437-1448, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36974813

RESUMO

BACKGROUND/AIM: Urothelial carcinoma (UC) of the urinary bladder is the second most common tumor in the field of urology and is characterized by a relatively aggressive growth behavior. New therapeutic approaches are required to improve the prognosis of affected patients. We hypothesized a link between dysregulation of eIFs and the development of UC. Therefore, in the present work, we investigated the expression behavior of eIF1, eIF1AY, eIF1AX, eIF2α, eIF3a, eIF3b, eIF4B, eIF4E, eIF4G, eIF5A, eIF5B, and eIF6 in UC compared with that in urothelial tissue. MATERIALS AND METHODS: Paraffin-embedded tumor tissue samples from 107 patients suffering from UC were examined. Seventy-six patients contained adjacent urothelial tissue. Three tumor tissue cylinders (tumor collective) and two urothelial tissue cylinders (control collective) were collected per patient and embedded in tissue microarray (TMA) blocks. Immunohistochemical staining of the TMA sections was then performed. The staining results were assessed semi-quantitatively. Staining intensities and immunoreactive scores (IRS) of both collectives were compared. In each case, a distinction was made between cytoplasmic and nuclear staining. RESULTS: Significant up-regulation of eIF1AY, eIF2α, eIF3a, eIF3b, eIF4B, eIF4G, eIF5B, and eIF6 was found in the cytoplasm of UC. In contrast, eIF1 and eIF5A were significantly down-regulated in the cytoplasm of UC. eIF5A and eIF6 were significantly down-regulated in the nuclei of UC. CONCLUSION: Dysregulation of eIFs in the urothelium of the urinary bladder is linked to carcinogenesis at this site.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Fator de Iniciação Eucariótico 4G/metabolismo , Prognóstico , Fator de Iniciação 2 em Eucariotos , Urotélio/patologia , Biomarcadores Tumorais/metabolismo
3.
Front Oncol ; 12: 817916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574327

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor developing from the esophageal squamous epithelium, and is the most common histological subtype of esophageal cancer (EC). EC ranks 10th in morbidity and sixth in mortality worldwide. The morbidity and mortality rates in China are both higher than the world average. Current treatments of ESCC are surgical treatment, radiotherapy, and chemotherapy. Neoadjuvant chemoradiotherapy plus surgical resection is recommended for advanced patients. However, it does not work in the significant promotion of overall survival (OS) after such therapy. Research on targeted therapy in ESCC mainly focus on EGFR and PD-1, but neither of the targeted drugs can significantly improve the 3-year and 5-year survival rates of disease. Phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway is an important survival pathway in tumor cells, associated with its aggressive growth and malignant progression. Specifically, proliferation, apoptosis, autophagy, and so on. Related genetic alterations of this pathway have been investigated in ESCC, such as PI3K, AKT and mTOR-rpS6K. Therefore, the PI3K/AKT/mTOR pathway seems to have the capability to serve as research hotspot in the future. Currently, various inhibitors are being tested in cells, animals, and clinical trials, which targeting at different parts of this pathway. In this work, we reviewed the research progress on the PI3K/AKT/mTOR pathway how to influence biological behaviors in ESCC, and discussed the interaction between signals downstream of this pathway, especially eukaryotic translation initiation factors (eIFs) and the development and progression of ESCC, to provide reference for the identification of new therapeutic targets in ESCC.

4.
Trends Cell Biol ; 32(9): 762-772, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35466028

RESUMO

Translation factors have traditionally been viewed as proteins that drive ribosome function and ensure accurate mRNA translation. Recent discoveries have highlighted that these factors can also moonlight in gene regulation, but through functions distinct from their canonical roles in protein synthesis. Notably, the additional functions that translation factors encode are diverse, ranging from transcriptional control and extracellular signaling to RNA binding, and are highly regulated in response to external cues and the intrinsic cellular state. Thus, this multifunctionality of translation factors provides an additional mechanism for exquisite control of gene expression.


Assuntos
Biossíntese de Proteínas , Ribossomos , Regulação da Expressão Gênica , Humanos , Proteínas/metabolismo , Ribossomos/genética , Ribossomos/metabolismo
5.
Int J Mol Sci ; 23(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408777

RESUMO

Adenomyosis, endometriosis, endometritis, and typical endometrial hyperplasia are common non-cancerous diseases of the endometrium that afflict many women with life-impacting consequences. The mammalian target of the rapamycin (mTOR) pathway interacts with estrogen signaling and is known to be dysregulated in endometrial cancer. Based on this knowledge, we attempt to investigate the role of mTOR signaling in benign endometrial diseases while focusing on how the interplay between mTOR and eukaryotic translation initiation factors (eIFs) affects their development. In fact, mTOR overactivity is apparent in adenomyosis, endometriosis, and typical endometrial hyperplasia, where it promotes endometrial cell proliferation and invasiveness. Recent data show aberrant expression of various components of the mTOR pathway in both eutopic and ectopic endometrium of patients with adenomyosis or endometriosis and in hyperplastic endometrium as well. Moreover, studies on endometritis show that derangement of mTOR signaling is linked to the establishment of endometrial dysfunction caused by chronic inflammation. This review shows that inhibition of the mTOR pathway has a promising therapeutic effect in benign endometrial conditions, concluding that mTOR signaling dysregulation plays a critical part in their pathogenesis.


Assuntos
Adenomiose , Hiperplasia Endometrial , Endometriose , Endometrite , Doenças Uterinas , Adenomiose/metabolismo , Adenomiose/patologia , Hiperplasia Endometrial/patologia , Endometriose/patologia , Endometrite/patologia , Endométrio/metabolismo , Feminino , Humanos , Sirolimo , Serina-Treonina Quinases TOR/metabolismo , Doenças Uterinas/patologia
6.
Cells ; 11(3)2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35159342

RESUMO

Viral infections or persistent alcohol or drug abuse, together with intrinsic factors, lead to hepatitis, which often ends in the development of liver cirrhosis or hepatocellular carcinoma (HCC). With this review, we describe inflammatory liver diseases, such as acute liver failure, virus-induced hepatitis, alcoholic- and non-alcoholic steatohepatitis, and autoimmune hepatitis, and highlight their driving mechanisms. These include external factors such as alcohol misuse, viral infection and supernutrition, as well as intrinsic parameters such as genetic disposition and failure, in immune tolerance. Additionally, we describe what is known about the translational machinery within all these diseases. Distinct eukaryotic translation initiation factors (eIFs) with specific functional roles and aberrant expression in HCC are reported. Many alterations to the translational machinery are already triggered in the precancerous lesions described in this review, highlighting mTOR pathway proteins and eIFs to emphasize their putative clinical relevance. Here, we identified a lack of knowledge regarding the roles of single eIF proteins. A closer investigation will help to understand and treat HCC as well as the antecedent diseases.


Assuntos
Carcinoma Hepatocelular , Hepatite Viral Humana , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Carcinogênese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Etanol , Humanos , Inflamação , Cirrose Hepática , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Serina-Treonina Quinases TOR
7.
Cell Rep ; 37(5): 109934, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34731628

RESUMO

Fragile X-related protein-1 (FXR1) gene is highly amplified in patients with ovarian cancer, and this amplification is associated with increased expression of both FXR1 mRNA and protein. FXR1 expression directly associates with the survival and proliferation of cancer cells. Surface sensing of translation (SUnSET) assay demonstrates that FXR1 enhances the overall translation in cancer cells. Reverse-phase protein array (RPPA) reveals that cMYC is the key target of FXR1. Mechanistically, FXR1 binds to the AU-rich elements (ARE) present within the 3' untranslated region (3'UTR) of cMYC and stabilizes its expression. In addition, the RGG domain in FXR1 interacts with eIF4A1 and eIF4E proteins. These two interactions of FXR1 result in the circularization of cMYC mRNA and facilitate the recruitment of eukaryotic translation initiation factors to the translation start site. In brief, we uncover a mechanism by which FXR1 promotes cMYC levels in cancer cells.


Assuntos
Fator de Iniciação 4F em Eucariotos/metabolismo , Neoplasias Ovarianas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas , Elementos Ricos em Adenilato e Uridilato , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Fator de Iniciação 4F em Eucariotos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Nus , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Iniciação Traducional da Cadeia Peptídica , Proteínas Proto-Oncogênicas c-myc/genética , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Carga Tumoral
8.
Cancers (Basel) ; 13(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807050

RESUMO

Glioblastoma (GBM) is an utterly devastating cerebral neoplasm and current therapies only marginally improve patients' overall survival (OS). The PI3K/AKT/mTOR pathway participates in gliomagenesis through regulation of cell growth and proliferation. Since it is an upstream regulator of the rate-limiting translation initiation step of protein synthesis, controlled by eukaryotic initiation factors (eIFs), we aimed for a profound basic characterization of 17 eIFs to identify potential novel therapeutic targets for gliomas. Therefore, we retrospectively analyzed expressions of mTOR-related proteins and eIFs in human astrocytoma samples (WHO grades I-IV) and compared them to non-neoplastic cortical control brain tissue (CCBT) using immunoblot analyses and immunohistochemistry. We examined mRNA expression using qRT-PCR and additionally performed in silico analyses to observe the influence of eIFs on patients' survival. Protein and mRNA expressions of eIF3B, eIF3I, eIF4A1, eIF4H, eIF5 and eIF6 were significantly increased in high grade gliomas compared to CCBT and partially in low grade gliomas. However, short OS was only associated with high eIF3I gene expression in low grade gliomas, but not in GBM. In GBM, high eIF4H gene expression significantly correlated with shorter patient survival. In conclusion, we identified eIF3I and eIF4H as the most promising targets for future therapy for glioma patients.

9.
Cancers (Basel) ; 12(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066449

RESUMO

Gastrointestinal stromal tumor (GIST) originates from interstitial cells of Cajal (ICCs) in the myenteric plexus of the gastrointestinal tract. Most GISTs arise due to mutations of KIT and PDGFRA gene activation, encoding the receptor tyrosine kinase (RTK). The clinical use of the RTK inhibitor imatinib has significantly improved the management of GIST patients; however, imatinib resistance remains a challenge. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway is a critical survival pathway for cell proliferation, apoptosis, autophagy and translation in neoplasms. Constitutive autophosphorylation of RTKs has an impact on the activation of the PI3K/AKT/mTOR pathway. In several preclinical and early-stage clinical trials PI3K/AKT/mTOR signaling inhibition has been considered as a promising targeted therapy strategy for GISTs. Various inhibitory drugs targeting different parts of the PI3K/AKT/mTOR pathway are currently being investigated in phase I and phase II clinical trials. This review highlights the progress for PI3K/AKT/mTOR-dependent mechanisms in GISTs, and explores the relationship between mTOR downstream signals, in particular, eukaryotic initiation factors (eIFs) and the development of GISTs, which may be instrumental for identifying novel therapeutic targets.

10.
Biochem Cell Biol ; 98(4): 502-510, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32008367

RESUMO

The natural product pateamineA (PatA) is a highly potent antiproliferative agent. PatA and the simplified analog desmethyl, desamino pateamineA (DMDAPatA) have exhibited cytotoxicity selective for rapidly proliferating cells, and have been shown to inhibit cap-dependent translation initiation through binding to eIF4A (eukaryotic initiation factor 4A) of the eIF4F complex. PatA and DMDAPatA are both known to stimulate the RNA-dependent ATPase, and ATP-dependent RNA helicase activities of eIF4A. The impact of other eIF4F components, eIF4E and eIF4G, on DMDAPatA action were investigated in vitro and in cultured mammalian cells. The perturbation of the eIF4A-eIF4G association was found to be eIF4E- and mRNA cap-dependent. An inhibitory effect on helicase activity of eIF4A was observed when it was part of a complex that mimicked the eIF4F complex. We propose a model of action for DMDAPatA (and by supposition PatA) where the cellular activity of the compound is dependent on an "active" eIF4F complex.


Assuntos
Adenosina Trifosfatases/metabolismo , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Fator de Iniciação 4A em Eucariotos/antagonistas & inibidores , Macrolídeos/química , Macrolídeos/farmacologia , Neoplasias/tratamento farmacológico , RNA Mensageiro/metabolismo , Tiazóis/química , Tiazóis/farmacologia , Adenosina Trifosfatases/genética , Produtos Biológicos , Linhagem Celular , Proliferação de Células , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , RNA Mensageiro/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
11.
Int J Mol Sci ; 20(3)2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30764584

RESUMO

The mTOR pathway is in the process of establishing itself as a key access-point of novel oncological drugs and targeted therapies. This is also reflected by the growing number of mTOR pathway genes included in commercially available next-generation sequencing (NGS) oncology panels. This review summarizes the portfolio of medium sized diagnostic, as well as research destined NGS panels and their coverage of the mTOR pathway, including 16 DNA-based panels and the current gene list of Foundation One as a major reference entity. In addition, we give an overview of interesting, mTOR-associated somatic mutations that are not yet incorporated. Especially eukaryotic translation initiation factors (eIFs), a group of mTOR downstream proteins, are on the rise as far as diagnostics and drug targeting in precision medicine are concerned. This review aims to raise awareness for the true coverage of NGS panels, which should be valuable in selecting the ideal platform for diagnostics and research.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Fatores de Iniciação em Eucariotos/genética , Fatores de Iniciação em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Mutação , Neoplasias/genética , Serina-Treonina Quinases TOR/genética
12.
RNA Biol ; 14(10): 1299-1305, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28277937

RESUMO

Translation is fundamental for many biologic processes as it enables cells to rapidly respond to stimuli without requiring de novo mRNA synthesis. The mammalian/mechanistic target of rapamycin (mTOR) is a key regulator of translation. Although mTOR affects global protein synthesis, translation of a subset of mRNAs appears to be exceptionally sensitive to changes in mTOR activity. Recent efforts to catalog these mTOR-sensitive mRNAs resulted in conflicting results. Whereas ribosome-profiling almost exclusively identified 5'-terminal oligopyrimidine (TOP) mRNAs as mTOR-sensitive, polysome-profiling suggested that mTOR also regulates translation of non-TOP mRNAs. This inconsistency was explained by analytical and technical biases limiting the efficiency of ribosome-profiling in detecting mRNAs showing differential translation. Moreover, genome-wide characterization of 5'UTRs of non-TOP mTOR-sensitive mRNAs revealed 2 subsets of transcripts which differ in their requirement for translation initiation factors and biologic functions. We summarize these recent advances and their impact on the understanding of mTOR-sensitive translation.


Assuntos
Biossíntese de Proteínas , Ribossomos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Regiões 5' não Traduzidas , Animais , Regulação da Expressão Gênica , Humanos , RNA Mensageiro/química , RNA Mensageiro/genética
13.
Biochim Biophys Acta ; 1849(11): 1313-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26381322

RESUMO

Eukaryotic translation initiation is an intricate and multi-step process that includes 43S Pre-Initiation Complex (PIC) assembly, attachment of the PIC to the mRNA, scanning, start codon selection and 60S subunit joining. Translation initiation of most mRNAs involves recognition of a 5'end m7G cap and ribosomal scanning in which the 5' UTR is checked for complementarity with the AUG. There is however an increasing number of mRNAs directing translation initiation that deviate from the predominant mechanism. In this review we summarize the canonical translation initiation process and describe non-canonical mechanisms that are cap-dependent but operate without scanning. In particular we focus on several examples of translation initiation driven either by mRNAs with extremely short 5' leaders or by highly complex 5' UTRs that promote ribosome shunting.


Assuntos
Iniciação Traducional da Cadeia Peptídica/fisiologia , Capuzes de RNA/metabolismo , Ribossomos/metabolismo , Animais , Humanos , Capuzes de RNA/genética , Ribossomos/genética
14.
Annu Rev Biochem ; 83: 779-812, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24499181

RESUMO

In eukaryotes, the translation initiation codon is generally identified by the scanning mechanism, wherein every triplet in the messenger RNA leader is inspected for complementarity to the anticodon of methionyl initiator transfer RNA (Met-tRNAi). Binding of Met-tRNAi to the small (40S) ribosomal subunit, in a ternary complex (TC) with eIF2-GTP, is stimulated by eukaryotic initiation factor 1 (eIF1), eIF1A, eIF3, and eIF5, and the resulting preinitiation complex (PIC) joins the 5' end of mRNA preactivated by eIF4F and poly(A)-binding protein. RNA helicases remove secondary structures that impede ribosome attachment and subsequent scanning. Hydrolysis of eIF2-bound GTP is stimulated by eIF5 in the scanning PIC, but completion of the reaction is impeded at non-AUG triplets. Although eIF1 and eIF1A promote scanning, eIF1 and possibly the C-terminal tail of eIF1A must be displaced from the P decoding site to permit base-pairing between Met-tRNAi and the AUG codon, as well as to allow subsequent phosphate release from eIF2-GDP. A second GTPase, eIF5B, catalyzes the joining of the 60S subunit to produce an 80S initiation complex that is competent for elongation.


Assuntos
Fator de Iniciação 1 em Eucariotos/metabolismo , Fator de Iniciação 3 em Eucariotos/metabolismo , Fator de Iniciação 5 em Eucariotos/metabolismo , RNA de Transferência de Metionina/genética , Subunidades Ribossômicas Menores de Eucariotos/química , Animais , Pareamento de Bases , Sítios de Ligação , Códon de Iniciação , Guanosina Trifosfato/química , Humanos , Hidrólise , Metionina/química , Ligação Proteica , RNA Helicases/química , Ribossomos/química , Tetrahymena
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