RESUMO
Lagerstroemia ovalifolia Teijsm. & Binn. (LO) (crape myrtle) has reportedly been used as traditional herbal medicine (THM) in Java, Indonesia. Our previous study revealed that the LO leaf extract (LOLE) exerted anti-inflammatory effects on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Based on this finding, the current study aimed to evaluate the protective effects of LOLE in a mouse model of LPS-induced acute lung injury (ALI). The results showed that treatment with LPS enhanced the inflammatory cell influx into the lungs and increased the number of macrophages and the secretion of the inflammatory cytokines in the bronchoalveolar lavage fluid (BALF) of mice. However, these effects were notably abrogated with LOLE pretreatment. Furthermore, the increase of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and monocyte chemoattractant protein-1 (MCP-1) expression in the lung tissues of mice with ALI was also reversed by LOLE. In addition, LOLE significantly suppressed the LPS-induced activation of the MAPK/NF-κB signaling pathway and led to heme oxygenase-1 (HO-1) induction in the lungs. Additionally, in vitro experiments showed that LOLE enhanced the expression of HO-1 in RAW264.7 macrophages. The aforementioned findings collectively indicate that LOLE exerts an ameliorative effect on inflammatory response in the airway of ALI mice.
Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Lagerstroemia/química , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Anti-Inflamatórios/farmacologia , Quimiocina CCL2 , Ciclo-Oxigenase 2 , Citocinas/metabolismo , Heme Oxigenase-1 , Indonésia , Macrófagos/efeitos dos fármacos , Masculino , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II , Folhas de Planta/química , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacosRESUMO
Focal adhesion kinase (FAK) is overexpressed in highly invasive and metastatic cancers. To identify novel FAK inhibitors, we designed and synthesized various thieno[3,2-d]pyrimidine derivatives. An intensive structure-activity relationship (SAR) study led to the identification of 26 as a lead. Moreover, 26, a multitargeted kinase inhibitor, possesses excellent potencies against FLT3 mutants as well as FAK. Gratifyingly, 26 remarkably inhibits recalcitrant FLT3 mutants, including F691L, that cause drug resistance. Importantly, 26 is superior to PF-562271 in terms of apoptosis induction, anchorage-independent growth inhibition, and tumor burden reduction in the MDA-MB-231 xenograft mouse model. Also, 26 causes regression of tumor growth in the MV4-11 xenograft mouse model, indicating that it could be effective against acute myeloid leukemia (AML). Finally, in an orthotopic mouse model using MDA-MB-231, 26 remarkably prevents metastasis of orthotopic tumors to lymph nodes. Taken together, the results indicate that 26 possesses potential therapeutic value against highly invasive cancers and relapsed AML.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Tiofenos/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Molecular , Metástase Neoplásica/prevenção & controle , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/síntese química , Pirimidinas/metabolismo , Pirimidinas/farmacologia , Relação Estrutura-Atividade , Tiofenos/síntese química , Tiofenos/metabolismo , Tiofenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/metabolismoRESUMO
Increased proliferation and protein synthesis are characteristics of transformed and tumor cells. Although the components of the translation machinery are often dysregulated in cancer, the role of tRNAs in cancer cells has not been well studied. Nevertheless, the number of related studies has recently started increasing. With the development of high throughput technologies such as next-generation sequencing, genome-wide differential tRNA expression patterns in breast cancer-derived cell lines and breast tumors have been investigated. The genome-wide transcriptomics analyses have been linked with many studies for functional and phenotypic characterization, whereby tRNAs or tRNA-related fragments have been shown to play important roles in breast cancer regulation and as promising prognostic biomarkers. Here, we review their expression patterns, functions, prognostic value, and potential therapeutic use as well as related technologies.
Assuntos
Neoplasias da Mama , Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , RNA de Transferência/genéticaRESUMO
BACKGROUND AND AIMS: Endobiliary brushings are routinely used in the diagnosis, treatment, and prognostication of biliary strictures. However, standard Papanicolaou (Pap) staining has a low sensitivity in this setting, and the accuracy of brush cytology has not been established for indeterminate strictures. We therefore evaluated the diagnostic merit of methionyl-transfer RNA synthetase 1 (MARS1) immunofluorescence (IF) staining in such cytologic specimens. METHODS: During ERCP, endobiliary brushings were obtained from patients with extrahepatic biliary strictures prospectively enrolled at 6 tertiary hospitals. Using liquid-based cytologic preparations of these samples, we performed Pap and MARS1 IF staining. RESULTS: In total, 240 patients were eligible; of these, we compared the Pap and MARS1 IF staining results of 218 (malignant, 157; benign, 61). By conventional Pap staining, the diagnoses were distributed as follows: malignant, 55; suspicious of malignancy, 60; atypical, 45; negative for malignancy, 58. MARS1 IF staining was strongly positive in malignant biliary stricture but not so in specimens negative for malignancy. The diagnostic parameters (sensitivity, specificity, positive predictive value, negative predictive value, and accuracy) of the MARS1 IF (93.6%, 96.7%, 98.7%, 85.5%, and 94.5%, respectively) and conventional Pap (73.2%, 100%, 100%, 59.2%, and 80.7%, respectively) staining methods differed significantly (P < .0001). CONCLUSIONS: The high sensitivity and accuracy of MARS1 IF staining enabled the detection of malignancy in patients with biliary strictures. Further prospective studies are needed to validate our findings. (Clinical trial registration number: NCT03708445.).
Assuntos
Neoplasias dos Ductos Biliares , Colestase , Metionina tRNA Ligase , Colangiopancreatografia Retrógrada Endoscópica , Constrição Patológica , Humanos , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
Recently, non-canonical roles of Lysyl-tRNA Synthetase (KRS), which is associated with cell migration and cancer metastasis, have been reported. Therefore, KRS has emerged as a promising target for the treatment of cell migration-related diseases, especially cancer metastasis, although the satisfying chemical inhibitors targeting KRS have not yet been identified. Here, we report the discovery of novel, mechanistically unique, and potent cell migration inhibitors targeting KRS, including the chemical and biological studies on the most effective N,N-dialkylthiazolo [5,4-b]pyridin-2-amine (SL-1910). SL-1910 exhibited highly potent migration inhibition (EC50 = 81 nM against the mutant KRS-overexpressed MDA-MB-231 cells) and was superior to the previously reported KRS inhibitor (migration inhibitory EC50 = 8.5 µM against H226 cells). The KRS protein binding study via fluorescence-based binding titration and KRS protein 2D-NMR mapping study, in vitro concentration-dependent cell migration inhibition, and in vivo anti-metastatic activity of SL-1910, which consists of a new scaffold, have been reported in this study. In addition, in vitro absorption, distribution, metabolism, and excretion studies and mouse pharmacokinetics experiments for SL-1910 were conducted.
Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Lisina-tRNA Ligase/antagonistas & inibidores , Piridinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Feminino , Humanos , Lisina-tRNA Ligase/metabolismo , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Relação Estrutura-AtividadeRESUMO
To understand the potential effects of cancer cells on surrounding normal mammary epithelial cells, we performed direct co-culture of non-tumorigenic mammary epithelial MCF10A cells and various breast cancer cells. Firstly, we observed dynamic cell-cell interactions between the MCF10A cells and breast cancer cells including lamellipodia or nanotube-like contacts and transfer of extracellular vesicles. Co-cultured MCF10A cells exhibited features of epithelial-mesenchymal transition, and showed increased capacity of cell proliferation, migration, colony formation, and 3-dimensional sphere formation. Direct co-culture showed most distinct phenotype changes in MCF10A cells followed by conditioned media treatment and indirect co-culture. Transcriptome analysis and phosphor-protein array suggested that several cancer-related pathways are significantly dysregulated in MCF10A cells after the direct co-culture with breast cancer cells. S100A8 and S100A9 showed distinct up-regulation in the co-cultured MCF10A cells and their microenvironmental upregulation was also observed in the orthotropic xenograft of syngeneic mouse mammary tumors. When S100A8/A9 overexpression was induced in MCF10A cells, the cells showed phenotypic features of directly co-cultured MCF10A cells in terms of in vitro cell behaviors and signaling activities suggesting a S100A8/A9-mediated transition program in non-tumorigenic epithelial cells. This study suggests the possibility of dynamic cell-cell interactions between non-tumorigenic mammary epithelial cells and breast cancer cells that could lead to a substantial transition in molecular and functional characteristics of mammary epithelial cells.
Assuntos
Neoplasias da Mama/metabolismo , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Comunicação Celular , Células Epiteliais/metabolismo , Glândulas Mamárias Humanas/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Células Epiteliais/patologia , Feminino , Humanos , Glândulas Mamárias Humanas/patologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Aminoacyl-tRNA synthetase-interacting multifunctional protein 2 (AIMP2) is a non-enzymatic component required for the multi-tRNA synthetase complex. While exon 2 skipping alternatively spliced variant of AIMP2 (AIMP2-DX2) compromises AIMP2 activity and is associated with carcinogenesis, its clinical potential awaits further validation. Here, we found that AIMP2-DX2/AIMP2 expression ratio is strongly correlated with major cancer signaling pathways and poor prognosis, particularly in acute myeloid leukemia (AML). Analysis of a clinical patient cohort revealed that AIMP2-DX2 positive AML patients show decreased overall survival and progression-free survival. We also developed targeted RNA-sequencing and single-molecule RNA-FISH tools to quantitatively analyze AIMP2-DX2/AIMP2 ratios at the single-cell level. By subclassifying hematologic cancer cells based on their AIMP2-DX2/AIMP2 ratios, we found that downregulating AIMP2-DX2 sensitizes cells to anticancer drugs only for a subgroup of cells while it has adverse effects on others. Collectively, our study establishes AIMP2-DX2 as a potential biomarker and a therapeutic target for hematologic cancer.
Assuntos
Processamento Alternativo , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/genética , Proteínas Nucleares/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias Hematológicas/mortalidade , Humanos , Processamento de Imagem Assistida por Computador , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Paclitaxel/farmacologia , Prognóstico , Análise de Célula Única , Adulto JovemRESUMO
AIMP2-DX2, an exon 2-deleted splice variant of AIMP2 (aminoacyl-tRNA synthetase-interacting multifunctional protein 2), is highly expressed in lung cancer and involved in tumor progression in vivo. Oncogenic function of AIMP2-DX2 and its correlation with poor prognosis of cancer patients have been well established; however, the application of this potentially important biomarker to cancer research and diagnosis has been hampered by a lack of antibodies specific for the splice variant, possibly due to the poor immunogenicity and/or stability of AIMP2-DX2. In this study a monoclonal antibody, H5, that specifically recognizes AIMP2-DX2 and its isoforms was generated via rabbit immunization and phage display techniques, using a short peptide corresponding to the exon 1/3 junction sequence as an antigen. Furthermore, based on mutagenesis, limited cleavage, and mass spectrometry studies, it is also suggested that the endogenous isoform of AIMP2-DX2 recognized by H5 is produced by proteolytic cleavage of 33 amino acids from N-terminus and is capable of inducing cell proliferation similarly to the uncleaved protein. H5 monoclonal antibody is applicable to enzyme-linked immunosorbent assay, immunoblot, immunofluorescence, and immunohistochemistry, and expected to be a valuable tool for detecting AIMP2-DX2 with high sensitivity and specificity for research and diagnostic purposes.
Assuntos
Anticorpos Monoclonais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Proteínas Nucleares/genética , Isoformas de Proteínas/genética , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Células Cultivadas , Cricetulus , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/isolamento & purificação , Proteínas Nucleares/metabolismo , CoelhosRESUMO
BACKGROUND AND AIMS: Identifying malignant biliary strictures using endobiliary brushing cytology specimens is important for treatment decision-making and prognosis prediction. The sensitivity of brushing cytology specimens based on Papanicolaou (Pap) staining is low, which hampers accurate diagnosis of indeterminate strictures. Here, we assessed the diagnostic value of immunohistochemical (IHC) and immunofluorescence (IF) staining for methionyl-tRNA synthetase 1 (MARS1). METHODS: Endobiliary brushing cytology specimens were obtained during ERCP from 80 patients with an extrahepatic biliary stricture. Pap and MARS1 IF staining were performed on liquid-based cytology slides derived from these specimens. Sections of bile duct adenocarcinoma and normal bile duct tissue were obtained from 45 patients who underwent surgery for malignant biliary stricture, and MARS1 levels were evaluated by IHC staining. RESULTS: MARS1 IF staining was applied to brushing cytology specimens, and the results showed strong signals in malignant biliary structures but not in the negative for malignancy specimens. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 70.4%, 96.2%, 97.4%, 56.8%, and 78.8%, respectively, for conventional Pap staining and 98.1%, 96.1%, 98.1%, 96.2%, and 97.5%, respectively, for MARS1 IF (P < .0001). When IHC staining was used, MARS1 was detected in 45 bile duct adenocarcinoma sections but not in 15 normal bile duct sections. Moreover, MARS1 mRNA and protein levels were significantly higher in bile duct adenocarcinoma sections according to polymerase chain reaction and Western blot, respectively. CONCLUSIONS: The high sensitivity and accuracy of MARS1 IF staining enabled detection of malignancy in patients with indeterminate biliary stricture. Further prospective studies are needed to validate our findings. (Clinical trial registration number: KCT 0003285.).
Assuntos
Neoplasias dos Ductos Biliares , Metionina tRNA Ligase , Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares , Ductos Biliares Intra-Hepáticos , Colangiopancreatografia Retrógrada Endoscópica , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade , Coloração e RotulagemRESUMO
Tyrosyl-tRNA synthetase ligates tyrosine to its cognate tRNA in the cytoplasm, but it can also be secreted through a noncanonical pathway. We found that extracellular tyrosyl-tRNA synthetase (YRS) exhibited proinflammatory activities. In addition to acting as a monocyte/macrophage chemoattractant, YRS initiated signaling through Toll-like receptor 2 (TLR2) resulting in NF-κB activation and release of tumor necrosis factor α (TNFα) and multiple chemokines, including MIP-1α/ß, CXCL8 (IL8), and CXCL1 (KC) from THP1 monocyte and peripheral blood mononuclear cell-derived macrophages. Furthermore, YRS up-regulated matrix metalloproteinase (MMP) activity in a TNFα-dependent manner in M0 macrophages. Because MMPs process a variety of intracellular proteins that also exhibit extracellular moonlighting functions, we profiled 10 MMPs for YRS cleavage and identified 55 cleavage sites by amino-terminal oriented mass spectrometry of substrates (ATOMS) positional proteomics and Edman degradation. Stable proteoforms resulted from cleavages near the start of the YRS C-terminal EMAPII domain. All of the MMPs tested cleaved at ADS386↓387LYV and VSG405↓406LVQ, generating 43- and 45-kDa fragments. The highest catalytic efficiency for YRS was demonstrated by MMP7, which is highly expressed by monocytes and macrophages, and by neutrophil-specific MMP8. MMP-cleaved YRS enhanced TLR2 signaling, increased TNFα secretion from macrophages, and amplified monocyte/macrophage chemotaxis compared with unprocessed YRS. The cleavage of YRS by MMP8, but not MMP7, was inhibited by tyrosine, a substrate of the YRS aminoacylation reaction. Overall, the proinflammatory activity of YRS is enhanced by MMP cleavage, which we suggest forms a feed-forward mechanism to promote inflammation.
Assuntos
Espaço Extracelular/enzimologia , Mediadores da Inflamação/metabolismo , Metaloproteinases da Matriz/metabolismo , Tirosina-tRNA Ligase/metabolismo , Quimiocinas/metabolismo , Quimiotaxia , Estabilidade Enzimática , Humanos , Macrófagos/metabolismo , Modelos Biológicos , Monócitos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Especificidade por Substrato , Células THP-1 , Receptor 2 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Tirosina/metabolismoRESUMO
PURPOSE: Identification of lymph node (LN) metastasis in non-small cell lung cancer (NSCLC) is critical for disease staging and selection of therapeutic modalities. Sometimes it is not possible to obtain LN core tissue by endobronchial ultrasound-guided transbronchial needle aspirate (EBUS-TBNA), resulting in low diagnostic yield. MATERIALS AND METHODS: In this study, 138 specimens were collected from 108 patients who underwent EBUS-TBNA under the suspicion of LN metastasis of NSCLC. Diagnostic yields of anti-CD45 and anti-methionyl-tRNA synthetase (MRS), immunofluorescent (IF) staining on cytology specimens were compared with those of conventional cytology and positron emission tomography-computed tomography (PET-CT). RESULTS: MRS was strongly expressed in NSCLC cells metastasized to LNs, but weakly expressed in cells at the periphery of the LN germinal center. The majority of cells were CD20 positive, although a few cells were either CD3 or CD14 positive, indicating that CD45 staining is required for discrimination of non-malignant LN constituent cells from NSCLC cells. When the diagnostic efficacy of MRS/CD45 IF staining was evaluated using 138 LN cellular aspirates from 108 patients through EBUS-TBNA, the sensitivity was 76.7% and specificity was 90.8%, whereas those of conventional cytology test were 71.8% and 100.0%, respectively. Combining the results of conventional cytology testing and those of PET-CT showed a sensitivity and specificity of 71.6% and 100%, and the addition of MRS/CD45 dual IF data to this combination increased sensitivity and specificity to 85.1% and 97.8%, respectively. CONCLUSION: MRS/CD45 dual IF staining showed good diagnostic performance and may be a good tool complementing conventional cytology test for determining LN metastasis of NSCLC.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/enzimologia , Metástase Linfática/diagnóstico , Metionina tRNA Ligase/metabolismo , Idoso , Antígenos CD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROCRESUMO
Tryptophanyl-tRNA synthetase (WRS) is a cytosolic aminoacyl-tRNA synthetase essential for protein synthesis. WRS is also one of a growing number of intracellular proteins that are attributed distinct noncanonical "moonlighting" functions in the extracellular milieu. Moonlighting aminoacyl-tRNA synthetases regulate processes such as inflammation, but how these multifunctional enzymes are themselves regulated remains unclear. Here, we demonstrate that WRS is secreted from human macrophages, fibroblasts, and endothelial cells in response to the proinflammatory cytokine interferon γ (IFNγ). WRS signaled primarily through Toll-like receptor 2 (TLR2) in macrophages, leading to phosphorylation of the p65 subunit of NF-κB with associated loss of NF-κB inhibitor α (IκB-α) protein. This signaling initiated secretion of tumor necrosis factor α (TNFα) and CXCL8 (IL8) from macrophages. We also demonstrated that WRS is a potent monocyte chemoattractant. Of note, WRS increased matrix metalloproteinase (MMP) activity in the conditioned medium of macrophages in a TNFα-dependent manner. Using purified recombinant proteins and LC-MS/MS to identify proteolytic cleavage sites, we demonstrated that multiple MMPs, but primarily macrophage MMP7 and neutrophil MMP8, cleave secreted WRS at several sites. Loss of the WHEP domain following cleavage at Met48 generated a WRS proteoform that also results from alternative splicing, designated Δ1-47 WRS. The MMP-cleaved WRS lacked TLR signaling and proinflammatory activities. Thus, our results suggest that moonlighting WRS promotes IFNγ proinflammatory activities, and these responses can be dampened by MMPs.
Assuntos
Inflamação/metabolismo , Interferon gama/metabolismo , Metaloproteinases da Matriz/metabolismo , Triptofano-tRNA Ligase/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Humanos , Macrófagos/metabolismoRESUMO
Aminoacyl-tRNA synthetases (ARSs) are essential enzymes for protein synthesis with evolutionarily conserved enzymatic mechanisms. Despite their similarity across organisms, scientists have been able to generate effective anti-infective agents based on the structural differences in the catalytic clefts of ARSs from pathogens and humans. However, recent genomic, proteomic and functionomic advances have unveiled unexpected disease-associated mutations and altered expression, secretion and interactions in human ARSs, revealing hidden biological functions beyond their catalytic roles in protein synthesis. These studies have also brought to light their potential as a rich and unexplored source for new therapeutic targets and agents through multiple avenues, including direct targeting of the catalytic sites, controlling disease-associated protein-protein interactions and developing novel biologics from the secreted ARS proteins or their parts. This Review addresses the emerging biology and therapeutic applications of human ARSs in diseases including autoimmune and rare diseases, and cancer.
Assuntos
Aminoacil-tRNA Sintetases , Descoberta de Drogas/métodos , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Aminoacil-tRNA Sintetases/metabolismo , Animais , Sítios de Ligação , Domínio Catalítico , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Evolução Molecular , Humanos , Infecções/tratamento farmacológico , Infecções/enzimologia , Terapia de Alvo Molecular , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/enzimologiaRESUMO
Various miRNAs play critical roles in the development and progression of solid tumors. In this study, we describe the role of miR-204-5p in limiting growth and progression of breast cancer. In breast cancer tissues, miR-204-5p was significantly downregulated compared with normal breast tissues, and its expression levels were associated with increased survival outcome in patients with breast cancer. Overexpression of miR-204-5p inhibited viability, proliferation, and migration capacity in human and murine breast cancer cells. In addition, miR-204-5p overexpression resulted in a significant alteration in metabolic properties of cancer cells and suppression of tumor growth and metastasis in mouse breast cancer models. The association between miR-204-5p expression and clinical outcomes of patients with breast cancer showed a nonlinear pattern that was reproduced in experimental assays of cancer cell behavior and metastatic capacities. Transcriptome and proteomic analysis revealed that various cancer-related pathways including PI3K/Akt and tumor-immune interactions were significantly associated with miR-204-5p expression. PIK3CB, a major regulator of PI3K/Akt pathway, was a direct target for miR-204-5p, and the association between PIK3CB-related PI3K/Akt signaling and miR-204-5p was most evident in the basal subtype. The sensitivity of breast cancer cells to various anticancer drugs including PIK3CB inhibitors was significantly affected by miR-204-5p expression. In addition, miR-204-5p regulated expression of key cytokines in tumor cells and reprogrammed the immune microenvironment by shifting myeloid and lymphocyte populations. These data demonstrate both cell-autonomous and non-cell-autonomous impacts of tumor suppressor miR-204-5p in breast cancer progression and metastasis. SIGNIFICANCE: This study demonstrates that regulation of PI3K/Akt signaling by miR-204-5p suppresses tumor metastasis and immune cell reprogramming in breast cancer.
Assuntos
Neoplasias da Mama/patologia , MicroRNAs/fisiologia , Metástase Neoplásica/genética , Microambiente Tumoral , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Feminino , Xenoenxertos , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Análise de SobrevidaRESUMO
Lysyl-tRNA synthetase (KRS) functions canonically in cytosolic translational processes. However, KRS is highly expressed in colon cancer, and localizes to distinct cellular compartments upon phosphorylations (i.e., the plasma membranes after T52 phosphorylation and the nucleus after S207 phosphorylation), leading to probably alternative noncanonical functions. It is unknown how other subcellular KRSs crosstalk with environmental cues during cancer progression. Here, we demonstrate that the KRS-dependent metastatic behavior of colon cancer spheroids within 3D gels requires communication between cellular molecules and extracellular soluble factors and neighboring cells. Membranous KRS and nuclear KRS were found to participate in invasive cell dissemination of colon cancer spheroids in 3D gels. Cancer spheroids secreted GAS6 via a KRS-dependent mechanism and caused the M2 polarization of macrophages, which activated the neighboring cells via secretion of FGF2/GROα/M-CSF to promote cancer dissemination under environmental remodeling via fibroblast-mediated laminin production. Analyses of tissues from clinical colon cancer patients and Krs-/+ animal models for cancer metastasis supported the roles of KRS, GAS6, and M2 macrophages in KRS-dependent positive feedback between tumors and environmental factors. Altogether, KRS in colon cancer cells remodels the microenvironment to promote metastasis, which can thus be therapeutically targeted at these bidirectional KRS-dependent communications of cancer spheroids with environmental cues.
Assuntos
Neoplasias do Colo/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Lisina-tRNA Ligase/biossíntese , Macrófagos/enzimologia , Proteínas de Neoplasias/biossíntese , Esferoides Celulares/enzimologia , Microambiente Tumoral , Animais , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/enzimologia , Fibroblastos/patologia , Células HCT116 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Lisina-tRNA Ligase/genética , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Metástase Neoplásica , Proteínas de Neoplasias/genética , Esferoides Celulares/patologiaRESUMO
While transfer-RNAs (tRNAs) are known to transport amino acids to ribosome, new functions are being unveiled from tRNAs and their fragments beyond protein synthesis. Here we show that phosphorylation of 90-kDa RPS6K (ribosomal proteins S6 kinase) was enhanced by tRNALeu overexpression under amino acids starvation condition. The phosphorylation of 90-kDa RPS6K was decreased by siRNA specific to tRNALeu and was independent to mTOR (mammalian target of rapamycin) signaling. Among the 90-kDa RPS6K family, RSK1 (ribosomal S6 kinase 1) and MSK2 (mitogen-and stress-activated protein kinase 2) were the major kinases phosphorylated by tRNALeu overexpression. Through SILAC (stable isotope labeling by/with amino acids in cell culture) and combined mass spectrometry analysis, we identified EBP1 (ErbB3-binding protein 1) as the tRNALeu-binding protein. We suspected that the overexpression of free tRNALeu would reinforce ErbB2/ErbB3 signaling pathway by disturbing the interaction between ErbB3 and EBP1, resulting in RSK1/MSK2 phosphorylation, improving cell proliferation and resistance to death. Analysis of samples from patients with breast cancer also indicated an association between tRNALeu overexpression and the ErbB2-positive population. Our results suggested a possible link between tRNALeu overexpression and RSK1/MSK2 activation and ErbB2/ErbB3 signaling.
Assuntos
Neoplasias da Mama/genética , RNA de Transferência de Leucina/genética , Receptor ErbB-2/genética , Receptor ErbB-3/genética , Proteínas Quinases S6 Ribossômicas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Aminoácidos/deficiência , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação da Expressão Gênica , Células HEK293 , Células HT29 , Humanos , Células MCF-7 , Camundongos , Células NIH 3T3 , Fosforilação , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA de Transferência de Leucina/antagonistas & inibidores , RNA de Transferência de Leucina/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Transdução de SinaisRESUMO
Although abnormal increases in the level or activity of cyclin-dependent kinase 4 (CDK4) occur frequently in cancer, the underlying mechanism is not fully understood. Here, we show that methionyl-tRNA synthetase (MRS) specifically stabilizes CDK4 by enhancing the formation of the complex between CDK4 and a chaperone protein. Knockdown of MRS reduced the CDK4 level, resulting in G0/G1 cell cycle arrest. The effects of MRS on CDK4 stability were more prominent in the tumor suppressor p16INK4a-negative cancer cells because of the competitive relationship of the two proteins for binding to CDK4. Suppression of MRS reduced cell transformation and the tumorigenic ability of a p16INK4a-negative breast cancer cell line in vivo. Further, the MRS levels showed a positive correlation with those of CDK4 and the downstream signals at high frequency in p16INK4a-negative human breast cancer tissues. This work revealed an unexpected functional connection between the two enzymes involving protein synthesis and the cell cycle.
RESUMO
Leucyl-tRNA synthetase (LRS) is known to function as leucine sensor in the mammalian target of rapamycin complex 1 (mTORC1) pathway. However, the pathophysiological significance of its activity is not well understood. Here, we demonstrate that the leucine sensor function for mTORC1 activation of LRS can be decoupled from its catalytic activity. We identified compounds that inhibit the leucine-dependent mTORC1 pathway by specifically inhibiting the GTPase activating function of LRS, while not affecting the catalytic activity. For further analysis, we selected one compound, BC-LI-0186, which binds to the RagD interacting site of LRS, thereby inhibiting lysosomal localization of LRS and mTORC1 activity. It also effectively suppressed the activity of cancer-associated MTOR mutants and the growth of rapamycin-resistant cancer cells. These findings suggest new strategies for controlling tumor growth that avoid the resistance to existing mTOR inhibitors resulting from cancer-associated MTOR mutations.Leucyl-tRNA synthetase (LRS) is a leucine sensor of the mTORC1 pathway. Here, the authors identify inhibitors of the GTPase activating function of LRS, not affecting its catalytic activity, and demonstrate that the leucine sensor function of LRS can be a new target for mTORC1 inhibition.
Assuntos
Leucina-tRNA Ligase/metabolismo , Leucina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Neoplasias/enzimologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Leucina-tRNA Ligase/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Monoméricas de Ligação ao GTP/genética , Neoplasias/genética , Neoplasias/metabolismo , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologiaRESUMO
Aminoacyl-tRNA synthetase-interacting multi-functional protein 2 (AIMP2) works as potent tumor suppressor, while its splicing variant lacking exon 2 (AIMP2-DX2) competes with AIMP2 for binding to target proteins and compromises its anti-tumor activity. Assuming that AIMP2 and its variant AIMP2-DX2 could be released out to human sera in pathological condition, we investigated the diagnostic and prognostic usefulness of autoantibodies against AIMP2 and AIMP2-DX2 by measuring their serum levels in 80 normal and lung cancer samples that were matched in age, gender and smoking status. The area under the curve of AIMP2-DX2, AIMP2, and AIMP2-DX2/AIMP2 autoantibody ratio was low (0.416, 0.579, and 0.357, respectively), suggesting limited diagnostic value. A total of 165 lung cancer patients were classified into low and high AIMP2-DX2, AIMP2, and AIMP2-DX2/AIMP2 based on the median expression of each parameter. The high AIMP2-DX2 group was older and had larger tumors (>3 cm) than the low AIMP2-DX2 group. The high AIMP2-DX2/AIMP2 group had higher CYFRA-21 levels and significantly shorter overall survival than the low AIMP2-DX2/AIMP2 group (18.6 vs. 48.9 months, P = 0.021, Log Rank Test). Taken together, autoantibodies against AIMP2-DX2 and AIMP2 are detectable in the human blood and the increased ratio of AIMP2-DX2/AIMP2 is related to poor clinical outcome of lung cancer.