RESUMEN
Rap2b, a proto-oncogene upregulated in colorectal cancer (CRC), undergoes protein S-palmitoylation at specific C-terminus sites (C176/C177). These palmitoylation sites are crucial for Rap2b localization on the plasma membrane (PM), as mutation of C176 or C177 results in cytosolic relocation of Rap2b. Our study demonstrates that Rap2b influences cell migration and invasion in CRC cells, independent of proliferation, and this activity relies on its palmitoylation. We identify ABHD17a as the depalmitoylating enzyme for Rap2b, altering PM localization and inhibiting cell migration and invasion. EGFR/PI3K signaling regulates Rap2b palmitoylation, with PI3K phosphorylating ABHD17a to modulate its activity. These findings highlight the potential of targeting Rap2b palmitoylation as an intervention strategy. Blocking the C176/C177 sites using an interacting peptide attenuates Rap2b palmitoylation, disrupting PM localization, and suppressing CRC metastasis. This study offers insights into therapeutic approaches targeting Rap2b palmitoylation for the treatment of metastatic CRC, presenting opportunities to improve patient outcomes.
Asunto(s)
Membrana Celular , Movimiento Celular , Neoplasias Colorrectales , Lipoilación , Proto-Oncogenes Mas , Proteínas de Unión al GTP rap , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/genética , Proteínas de Unión al GTP rap/metabolismo , Proteínas de Unión al GTP rap/genética , Membrana Celular/metabolismo , Animales , Línea Celular Tumoral , Metástasis de la Neoplasia , Transducción de Señal , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/metabolismo , Receptores ErbB/metabolismo , Proliferación CelularRESUMEN
Collective cell migration is crucial in various physiological processes, including wound healing, morphogenesis, and cancer metastasis. Adherens Junctions (AJs) play a pivotal role in regulating cell cohesion and migration dynamics during tissue remodeling. While the role and origin of the junctional mechanical tension at AJs have been extensively studied, the influence of the actin cortex structure and dynamics on junction plasticity remains incompletely understood. Moreover, the mechanisms underlying stress dissipation at junctions are not well elucidated. Here, we found that the ligand-independent phosphorylation of epithelial growth factor receptor (EGFR) downstream of de novo E-cadherin adhesion orchestrates a feedback loop, governing intercellular viscosity via the Rac pathway regulating actin dynamics. Our findings highlight how the E-cadherin-dependent EGFR activity controls the migration mode of collective cell movements independently of intercellular tension. This modulation of effective viscosity coordinates cellular movements within the expanding monolayer, inducing a transition from swirling to laminar flow patterns while maintaining a constant migration front speed. Additionally, we propose a vertex model with adjustable junctional viscosity, capable of replicating all observed cellular flow phenotypes experimentally.
Asunto(s)
Cadherinas , Movimiento Celular , Receptores ErbB , Fosforilación , Movimiento Celular/fisiología , Cadherinas/metabolismo , Receptores ErbB/metabolismo , Viscosidad , Humanos , Animales , Uniones Adherentes/metabolismo , PerrosRESUMEN
Acquired resistance is inevitable in the treatment of non-small cell lung cancer (NSCLC) with osimertinib, and one of the primary mechanisms responsible for this resistance is the epithelial-mesenchymal transition (EMT). We identify upregulation of the proviral integration site for Moloney murine leukemia virus 1 (PIM1) and functional inactivation of glycogen synthase kinase 3ß (GSK3ß) as drivers of EMT-associated osimertinib resistance. Upregulation of PIM1 promotes the growth, invasion, and resistance of osimertinib-resistant cells and is significantly correlated with EMT molecules expression. Functionally, PIM1 suppresses the ubiquitin-proteasome degradation of snail family transcriptional repressor 1 (SNAIL) and snail family transcriptional repressor 2 (SLUG) by deactivating GSK3ß through phosphorylation. The stability and accumulation of SNAIL and SLUG facilitate EMT and encourage osimertinib resistance. Furthermore, treatment with PIM1 inhibitors prevents EMT progression and re-sensitizes osimertinib-resistant NSCLC cells to osimertinib. PIM1/GSK3ß signaling is activated in clinical samples of osimertinib-resistant NSCLC, and dual epidermal growth factor receptor (EGFR)/PIM1 blockade synergistically reverse osimertinib-resistant NSCLC in vivo. These data identify PIM1 as a driver of EMT-associated osimertinib-resistant NSCLC cells and predict that PIM1 inhibitors and osimertinib combination therapy will provide clinical benefit in patients with EGFR-mutant NSCLC.
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Acrilamidas , Compuestos de Anilina , Carcinoma de Pulmón de Células no Pequeñas , Resistencia a Antineoplásicos , Transición Epitelial-Mesenquimal , Receptores ErbB , Glucógeno Sintasa Quinasa 3 beta , Neoplasias Pulmonares , Proteínas Proto-Oncogénicas c-pim-1 , Transducción de Señal , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Acrilamidas/farmacología , Acrilamidas/uso terapéutico , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Proteínas Proto-Oncogénicas c-pim-1/genética , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Compuestos de Anilina/farmacología , Compuestos de Anilina/uso terapéutico , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Ratones , Línea Celular Tumoral , Mutación/genética , Ratones Desnudos , Factores de Transcripción de la Familia Snail/metabolismo , Factores de Transcripción de la Familia Snail/genética , Indoles , PirimidinasRESUMEN
Non-small cell lung cancer (NSCLC) remains a significant challenge, as it is one of the leading causes of cancer-related deaths, and the development of resistance to anticancer therapy makes it difficult to treat. In this study, we investigated the anticancer mechanism of deoxybouvardin (DB), a cyclic hexapeptide, in gefitinib (GEF)-sensitive and -resistant NSCLC HCC827 cells. DB inhibited the viability and growth of HCC827 cells in a concentration- and time-dependent manner. In vitro kinase assay showed DB inhibited epidermal growth factor receptor (EGFR), mesenchymal-epithelial transition (MET), and AKT, and their phosphorylation was suppressed in HCC827 cells treated with DB. A molecular docking model suggested that DB interacts with these kinases in the ATP-binding pockets. DB induces ROS generation and cell cycle arrest. DB treatment of HCC827 cells leads to mitochondrial membrane depolarization. The induction of apoptosis through caspase activation was confirmed by Z-VAD-FMK treatment. Taken together, DB inhibited the growth of both GEF-sensitive and GEF-resistant NSCLC cells by targeting EGFR, MET, and AKT and inducing ROS generation and caspase activation. Further studies on DB can improve the treatment of chemotherapy-resistant NSCLC through the development of effective DB-based anticancer agents.
Asunto(s)
Apoptosis , Carcinoma de Pulmón de Células no Pequeñas , Receptores ErbB , Neoplasias Pulmonares , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas c-met , Transducción de Señal , Humanos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Receptores ErbB/metabolismo , Gefitinib/farmacología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Simulación del Acoplamiento Molecular , Péptidos Cíclicos/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
The epidermal growth factor (EGF) receptor (EGFR) is activated by the binding of one of seven EGF-like ligands to its ectodomain. Ligand binding results in EGFR dimerization and stabilization of the active receptor conformation subsequently leading to activation of downstream signaling. Aberrant activation of EGFR contributes to cancer progression through EGFR overexpression/amplification, modulation of its positive and negative regulators, and/or activating mutations within EGFR. EGFR targeted therapeutic antibodies prevent dimerization and interaction with endogenous ligands by binding the ectodomain of EGFR. However, these antibodies have had limited success in the clinic, partially due to EGFR ectodomain resistance mutations, and are only applicable to a subset of patients with EGFR-driven cancers. These limitations suggest that alternative EGFR targeted biologics need to be explored for EGFR-driven cancer therapy. To this end, we analyze the EGFR interfaces of known inhibitory biologics with determined structures in the context of endogenous ligands, using the Rosetta macromolecular modeling software to highlight the most important interactions on a per-residue basis. We use this analysis to identify the structural determinants of EGFR targeted biologics. We suggest that commonly observed binding motifs serve as the basis for rational design of new EGFR targeted biologics, such as peptides, antibodies, and nanobodies.
Asunto(s)
Receptores ErbB , Receptores ErbB/química , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Receptores ErbB/genética , Humanos , Productos Biológicos/química , Productos Biológicos/farmacología , Productos Biológicos/metabolismo , Modelos Moleculares , Unión Proteica , Sitios de Unión , Diseño de Fármacos , LigandosRESUMEN
Human epidermal growth factor receptors (HER)-also known as EGFR or ErbB receptors-are a subfamily of receptor tyrosine kinases (RTKs) that play crucial roles in cell growth, division, and differentiation. HER4 (ErbB4) is the least studied member of this family, partly because its expression is lower in later stages of development. Recent work has suggested that HER4 can play a role in metastasis by regulating cell migration and invasiveness; however, unlike EGFR and HER2, the precise role that HER4 plays in tumorigenesis is still unresolved. Early work on HER family proteins suggested that there are direct interactions between the four members, but to date, there has been no single study of all four receptors in the same cell line with the same biophysical method. Here, we quantitatively measure the degree of association between HER4 and the other HER family proteins in live cells with a time-resolved fluorescence technique called pulsed interleaved excitation fluorescence cross-correlation spectroscopy (PIE-FCCS). PIE-FCCS is sensitive to the oligomerization state of membrane proteins in live cells, while simultaneously measuring single-cell protein expression levels and diffusion coefficients. Our PIE-FCCS results demonstrate that HER4 interacts directly with all HER family members in the cell plasma membrane. The interaction between HER4 and other HER family members intensified in the presence of a HER4-specific ligand. Our work suggests that HER4 is a preferred dimerization partner for all HER family proteins, even in the absence of ligands.
Asunto(s)
Receptores ErbB , Multimerización de Proteína , Receptor ErbB-4 , Receptor ErbB-4/metabolismo , Receptor ErbB-4/química , Receptor ErbB-4/genética , Humanos , Receptores ErbB/metabolismo , Receptores ErbB/química , Receptores ErbB/genética , Espectrometría de FluorescenciaRESUMEN
Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (EGFR-TKI) approved for patients with EGFR T790M resistance mutations as first- or second-line treatment of EGFR-positive patients. Resistance to Osimertinib will inevitably develop, and the underlying mechanisms are largely unknown. In this study, we discovered that acquired resistance to Osimertinib is associated with abnormal DNA damage response (DDR) in lung adenocarcinoma cells. We discovered that the polycomb protein Lethal(3) Malignant Brain Tumor-Like Protein 1 (L3MBTL1) regulates chromatin structure, thereby contributing to DDR and Osimertinib resistance. EGFR oncogene inhibition reduced L3MBTL1 ubiquitination while stabilizing its expression in Osimertinib-resistant cells. L3MBTL1 reduction and treatment with Osimertinib significantly inhibited DDR and proliferation of Osimertinib-resistant lung cancer cells in vitro and in vivo. L3MBTL1 binds throughout the genome and plays an important role in EGFR-TKI resistance. It also competes with 53BP1 for H4K20Me2 and inhibits the development of drug resistance in Osimertinib-resistant lung cancer cells in vitro and in vivo. Our findings suggest that L3MBTL1 inhibition is a novel approach to overcoming EGFR-TKI-acquired resistance.
Asunto(s)
Acrilamidas , Adenocarcinoma del Pulmón , Compuestos de Anilina , Daño del ADN , Resistencia a Antineoplásicos , Epigénesis Genética , Receptores ErbB , Neoplasias Pulmonares , Humanos , Acrilamidas/farmacología , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Compuestos de Anilina/farmacología , Compuestos de Anilina/uso terapéutico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/metabolismo , Daño del ADN/efectos de los fármacos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Epigénesis Genética/efectos de los fármacos , Animales , Línea Celular Tumoral , Receptores ErbB/metabolismo , Receptores ErbB/genética , Ratones , Proteínas del Grupo Polycomb/metabolismo , Proteínas del Grupo Polycomb/genética , Ratones Desnudos , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53/genética , Inhibidores de Proteínas Quinasas/farmacología , Proliferación Celular/efectos de los fármacos , Ubiquitinación/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Indoles , PirimidinasRESUMEN
BACKGROUND: CD155 is a transmembrane protein that inhibits antitumor immune response and represents a predictor of worse prognosis in non-small-cell lung cancer (NSCLC). However, it remains unexplored its association with clinical characteristics and genomic status of Latin American patients. This study characterizes the CD155 expression and its clinical implications in this population. METHODS: Tissue biopsies from 86 patients with locally-advanced or metastatic NSCLC were assessed for CD155 protein expression, ALK rearrangements and EGFR mutations. Cutoff values for high CD155 expression (CD155high) were determined from receiver operating characteristic (ROC) curves according to 2-year survival. It was evaluated its association with clinicopathological features, median progression-free survival (mPFS) and overall survival (mOS). RESULTS: the cutoff score for CD155high was 155 in the entire cohort and in patients without oncogenic alterations, and it was 110 in patients with oncogenic alterations. Eighty-four patients (97.7%) were CD155 positive, of which fifty-six (65.0%) had CD155high. EGFR L858R mutation related to lower CD155 IHC score than exon 19 deletion. Individuals with CD155high showed a shorter mOS (13.0 vs. 30.8 months; HR: 1.96 [95% CI, 1.15-3.35]; p = 0.014). Patients without oncogenic alterations having a CD155high displayed shorter mPFS (1.6 vs. 6.4 months, HR: 2.09 [95% CI, 1.06-4.20]; p = 0.034) and mOS (2.9 vs. 23.1 months; HR: 1.27 [95% CI, 1.07- 4.42]; p = 0.032). Patients with oncogenic alterations having CD155high only showed a trend to shorter mOS (26.3 vs. 52.0 months; HR: 2.39 [95% CI, 0.98-5.83]; p = 0.058). CONCLUSION: CD155high is a predictor of worse outcomes in patients with advanced NSCLC, predominantly among those without oncogenic alterations. CD155 could be a potential biomarker and a molecular target in patients with poor responses to current therapies.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Receptores Virales , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Masculino , Femenino , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Persona de Mediana Edad , Pronóstico , Anciano , Receptores Virales/genética , Receptores Virales/metabolismo , Mutación/genética , Adulto , Receptores ErbB/metabolismo , Receptores ErbB/genética , Anciano de 80 o más Años , Curva ROCRESUMEN
Lung cancer and cachexia are the leading causes of cancer-related deaths worldwide. Cachexia is manifested by weight loss and white adipose tissue (WAT) atrophy. Limited nutritional supplements are conducive to lung cancer patients, whereas the underlying mechanisms are poorly understood. In this study, we used a murine cancer cachexia model to investigate the effects of a nutritional formula (NuF) rich in fish oil and selenium yeast as an adjuvant to enhance the drug efficacy of an EGFR inhibitor (Tarceva). In contrast to the healthy control, tumor-bearing mice exhibited severe cachexia symptoms, including tissue wasting, hypoalbuminemia, and a lower food efficiency ratio. Experimentally, Tarceva reduced pEGFR and HIF-1α expression. NuF decreased the expression of pEGFR and HIF-2α, suggesting that Tarceva and NuF act differently in prohibiting tumor growth and subsequent metastasis. NuF blocked LLC tumor-induced PTHrP and expression of thermogenic factor UCP1 and lipolytic enzymes (ATGL and HSL) in WAT. NuF attenuated tumor progression, inhibited PTHrP-induced adipose tissue browning, and maintained adipose tissue integrity by modulating heat shock protein (HSP) 72. Added together, Tarceva in synergy with NuF favorably improves cancer cachexia as well as drug efficacy.
Asunto(s)
Caquexia , Suplementos Dietéticos , Receptores ErbB , Aceites de Pescado , Lipólisis , Selenio , Termogénesis , Animales , Caquexia/tratamiento farmacológico , Caquexia/patología , Ratones , Selenio/farmacología , Selenio/uso terapéutico , Lipólisis/efectos de los fármacos , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inhibidores , Termogénesis/efectos de los fármacos , Aceites de Pescado/farmacología , Aceites de Pescado/uso terapéutico , Ratones Endogámicos C57BL , Masculino , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Tejido Adiposo Blanco/patología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismoRESUMEN
A novel group of indolyl-1,2,4-triazole-chalcone hybrids was designed, synthesized, and assessed for their anticancer activity. The synthesized compounds exhibited significant antiproliferative activity. Compounds 9a and 9e exhibited significant cancer inhibition with GI50 ranging from 3.69 to 20.40 µM and from 0.29 to >100 µM, respectively. Both compounds displayed a broad spectrum of anticancer activity with selectivity ratios ranging between 0.50-2.78 and 0.25-2.81 at the GI50 level, respectively. The synthesized compounds were also screened for their cytotoxicity by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazol (MTT) assay and for inhibition of epidermal growth factor receptor (EGFR) and c-MET (mesenchymal-epithelial transition factor). Some of the tested compounds exhibited significant inhibition against EGFR and/or c-MET. Compound 9b showed the highest c-MET inhibition (IC50 = 4.70 nM) compared to foretinib (IC50 = 2.5 nM). Compound 9d showed equipotent activity compared with erlotinib against EGFR (IC50 = 0.052 µM) and displayed significant c-MET inhibition with an IC50 value of 4.90 nM.
Asunto(s)
Antineoplásicos , Proliferación Celular , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB , Indoles , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas c-met , Triazoles , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Humanos , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-met/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Triazoles/farmacología , Triazoles/química , Triazoles/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Indoles/farmacología , Indoles/química , Indoles/síntesis química , Relación Dosis-Respuesta a Droga , Estructura Molecular , Línea Celular Tumoral , Chalconas/farmacología , Chalconas/síntesis química , Chalconas/química , Chalcona/farmacología , Chalcona/química , Chalcona/síntesis químicaRESUMEN
Most cancer-related deaths are due to the spread of tumour cells throughout the body-a process known as metastasis. While in the vasculature, these cells are referred to as circulating tumour cells (CTCs) and can be found as either single cells or clusters of cells (often including platelets), with the latter having the highest metastatic potential. However, the biology of CTC clusters is poorly understood, and there are no therapies that specifically target them. We previously developed an in vitro model system for CTC clusters and proposed a new extravasation model that involves cluster dissociation, adherence, and single-cell invasion in response to TGF-ß1 released by platelets. Here, we investigated TGF-ß1-induced gene expression changes in this model, focusing on genes for which targeted drugs are available. In addition to the upregulation of the TGF-ß1 signalling pathway, we found that (i) genes in the EGF/EGFR pathway, including those coding for EGFR and several EGFR ligands, were also induced, and (ii) Erlotinib and Osimertinib, two therapeutic EGFR/tyrosine kinase inhibitors, decreased the TGF-ß1-induced adherence and invasion of the CTC cluster-like line despite the line expressing wild-type EGFR. Overall, we suggest that EGFR inhibitors have the potential to decrease the dispersal of CTC clusters that respond to TGF-ß1 and overexpress EGFR (irrespective of its status) and thus could improve patient survival.
Asunto(s)
Receptores ErbB , Células Neoplásicas Circulantes , Factor de Crecimiento Transformador beta1 , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Humanos , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/efectos de los fármacos , Células Neoplásicas Circulantes/patología , Factor de Crecimiento Transformador beta1/metabolismo , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Clorhidrato de Erlotinib/farmacología , Transducción de Señal/efectos de los fármacos , Acrilamidas , Compuestos de Anilina , Indoles , PirimidinasAsunto(s)
Antineoplásicos , Receptores ErbB , Fosfatidilinositol 3-Quinasas , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéuticoRESUMEN
Chinese1 is the predominant Toxoplasma gondii lineage in China, and significant phenotypic differences are observed within the lineage. WH3 and WH6 are two representative strains of Chinese 1, which exhibit divergent virulence and pathogenicity in mice. However, virulence determinants and their modulating mechanisms remain elusive. A global genome expression analysis of the WH3 and WH6 transcriptional profiles identified microneme secretory protein 6 (MIC6), which may be associated with the phenotypic difference observed in WH3. In the present study, the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome-editing technique was used to generate a T. gondii microneme secretory protein (TgMIC6) knockout in WH3. Wild-type mice and different mouse and human cell lines were infected with the WH3, WH3-Δmic6, and WH6 strains. The survival rate of mice, related cytokine levels in serum, and the proliferation of parasites were observed. These results suggested that TgMIC6 is an important effector molecule that determines the differential virulence of WH3 in vivo and in vitro. Furthermore, MIC6 may enhance WH3 virulence via inhibition of host cell autophagy and activation of key molecules in the epidermal growth factor receptor (EGFR)-Akt-mammalian target of rapamycin (mTOR) classical autophagy pathway. CD40L was cleared in vivo by i.p injection of CD40L monoclonal antibody, and it was found that the virulence of WH3-Δmic6 to mice was restored to a certain extent in the absence of CD40L. This study elucidates the virulence determinants and immune escape strategies of Toxoplasma gondii in China. Moreover, these data will aid the development of effective strategies for the prevention and control of toxoplasmosis.
Asunto(s)
Autofagia , Proteínas Protozoarias , Toxoplasma , Animales , Femenino , Humanos , Ratones , Línea Celular , China , Sistemas CRISPR-Cas , Citocinas/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/genética , Fenotipo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Toxoplasma/patogenicidad , Toxoplasma/inmunología , Toxoplasma/genética , Toxoplasmosis/inmunología , Toxoplasmosis/parasitología , Toxoplasmosis Animal/inmunología , VirulenciaRESUMEN
It is well known how the precise localization of glioblastoma multiforme (GBM) predicts the direction of tumor spread in the surrounding neuronal structures. The aim of the present review is to reveal the lateralization of GBM by evaluating the anatomical regions where it is frequently located as well as the main molecular alterations observed in different brain regions. According to the literature, the precise or most frequent lateralization of GBM has yet to be determined. However, it can be said that GBM is more frequently observed in the frontal lobe. Tractus and fascicles involved in GBM appear to be focused on the corticospinal tract, superior longitudinal I, II and III fascicles, arcuate fascicle long segment, frontal strait tract, and inferior frontooccipital fasciculus. Considering the anatomical features of GBM and its brain involvement, it is logical that the main brain regions involved are the frontaltemporalparietaloccipital lobes, respectively. Although tumor volumes are higher in the right hemisphere, it has been determined that the prognosis of patients diagnosed with cancer in the left hemisphere is worse, probably reflecting the anatomical distribution of some detrimental alterations such as TP53 mutations, PTEN loss, EGFR amplification, and MGMT promoter methylation. There are theories stating that the right hemisphere is less exposed to external influences in its development as it is responsible for the functions necessary for survival while tumors in the left hemisphere may be more aggressive. To shed light on specific anatomical and molecular features of GBM in different brain regions, the present review article is aimed at describing the main lateralization pathways as well as gene mutations or epigenetic modifications associated with the development of brain tumors.
Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Glioblastoma/genética , Glioblastoma/patología , Glioblastoma/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Mutación , Glioma/genética , Glioma/patología , Glioma/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Pronóstico , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Metilasas de Modificación del ADN/genética , Metilasas de Modificación del ADN/metabolismoRESUMEN
Establishing a nonproductive, quiescent infection within monocytes is essential for the spread of human cytomegalovirus (HCMV). We investigated the mechanisms through which HCMV establishes a quiescent infection in monocytes. US28 is a virally encoded G protein-coupled receptor (GPCR) that is essential for silent infections within cells of the myeloid lineage. We found that preformed US28 was rapidly delivered to monocytes by HCMV viral particles, whereas the de novo synthesis of US28 was delayed for several days. A recombinant mutant virus lacking US28 (US28Δ) was unable to establish a quiescent infection, resulting in a fully productive lytic infection able to produce progeny virus. Infection with US28Δ HCMV resulted in the phosphorylation of the serine and threonine kinase Akt at Ser473 and Thr308, in contrast with the phosphorylation of Akt only at Ser473 after WT viral infection. Inhibiting the dual phosphorylation of Akt prevented the lytic replication of US28Δ, and ectopic expression of a constitutively phosphorylated Akt variant triggered lytic replication of wild-type HCMV. Mechanistically, we found that US28 was necessary and sufficient to attenuate epidermal growth factor receptor (EGFR) signaling induced during the entry of WT virus, which led to the site-specific phosphorylation of Akt at Ser473. Thus, particle-delivered US28 fine-tunes Akt activity by limiting HCMV-induced EGFR activation during viral entry, enabling quiescent infection in monocytes.
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Citomegalovirus , Receptores ErbB , Monocitos , Proteínas Proto-Oncogénicas c-akt , Proteínas Virales , Replicación Viral , Citomegalovirus/fisiología , Citomegalovirus/genética , Citomegalovirus/metabolismo , Humanos , Monocitos/virología , Monocitos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Fosforilación , Proteínas Virales/metabolismo , Proteínas Virales/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Virión/metabolismo , Virión/genética , Receptores de Quimiocina/metabolismo , Receptores de Quimiocina/genética , Infecciones por Citomegalovirus/metabolismo , Infecciones por Citomegalovirus/virología , Infecciones por Citomegalovirus/genética , Transducción de SeñalRESUMEN
Identifying biologically active ligands for membrane proteins is an important task in chemical biology. We report an approach to directly identify small molecule agonists against membrane proteins by selecting DNA-encoded libraries (DELs) on live cells. This method connects extracellular ligand binding with intracellular biochemical transformation, thereby biasing the selection toward agonist identification. We have demonstrated the methodology with three membrane proteins: epidermal growth factor receptor (EGFR), thrombopoietin receptor (TPOR), and insulin receptor (INSR). A â¼30 million and a 1.033 billion-compound DEL were selected against these targets, and novel agonists with subnanomolar affinity and low micromolar cellular activities have been discovered. The INSR agonists activated the receptor by possibly binding to an allosteric site, exhibited clear synergistic effects with insulin, and activated the downstream signaling pathways. Notably, the agonists did not activate the insulin-like growth factor 1 receptor (IGF-1R), a highly homologous receptor whose activation may lead to tumor progression. Collectively, this work has developed an approach toward "functional" DEL selections on the cell surface and may provide a widely applicable method for agonist discovery for membrane proteins.
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ADN , Receptores ErbB , Receptor de Insulina , Bibliotecas de Moléculas Pequeñas , Humanos , Receptor de Insulina/agonistas , Receptor de Insulina/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/síntesis química , ADN/química , ADN/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/agonistas , Proteínas de la Membrana/agonistas , Proteínas de la Membrana/metabolismo , Descubrimiento de Drogas , Células HEK293 , Ligandos , Antígenos CDRESUMEN
This work reports a cyclic peptide appended self-assembled scaffold that recognizes the membrane protein EGFR and arrests the EGFR signaling through multivalent interactions by assembly-induced aggregation. When incubated with cells, the oligomers of PAD-1 first recognize the overexpressed EGFR on cancer cell membranes for arresting EGFR, which then initiates cellular uptake through endocytosis. The accumulation of PAD-1 and EGFR in the lysosome results in the formation of nanofibers, leading to the lysosomal membrane permeabilization (LMP). These processes disrupt the homeostasis of EGFR and inhibit the downstream signaling transduction of EGFR for cancer cell survival. Moreover, LMP induced the release of protein aggregates that could generate endoplasmic reticulum (ER) stress, resulting in cancer cell death selectively. In vivo studies indicate the efficient antitumor efficiency of PAD-1 in tumor-bearing mice. As a first example, this work provides an alternative strategy for controlling protein behavior for tuning cellular events in living cells.
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Receptores ErbB , Lisosomas , Transducción de Señal , Humanos , Animales , Transducción de Señal/efectos de los fármacos , Receptores ErbB/metabolismo , Ratones , Línea Celular Tumoral , Lisosomas/metabolismo , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/química , Estrés del Retículo Endoplásmico/efectos de los fármacos , Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Endocitosis/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Proteínas de la Membrana/metabolismoRESUMEN
Bone cancer pain (BCP) represents a prevalent symptom among cancer patients with bone metastases, yet its underlying mechanisms remain elusive. This study investigated the transcriptional regulation mechanism of Kv7(KCNQ)/M potassium channels in DRG neurons and its involvement in the development of BCP in rats. We show that HDAC2-mediated transcriptional repression of kcnq2/kcnq3 genes, which encode Kv7(KCNQ)/M potassium channels in dorsal root ganglion (DRG), contributes to the sensitization of DRG neurons and the pathogenesis of BCP in rats. Also, HDAC2 requires the formation of a corepressor complex with MeCP2 and Sin3A to execute transcriptional regulation of kcnq2/kcnq3 genes. Moreover, EREG is identified as an upstream signal molecule for HDAC2-mediated kcnq2/kcnq3 genes transcription repression. Activation of EREG/EGFR-ERK-Runx1 signaling, followed by the induction of HDAC2-mediated transcriptional repression of kcnq2/kcnq3 genes in DRG neurons, leads to neuronal hyperexcitability and pain hypersensitivity in tumor-bearing rats. Consequently, the activation of EREG/EGFR-ERK-Runx1 signaling, along with the subsequent transcriptional repression of kcnq2/kcnq3 genes by HDAC2 in DRG neurons, underlies the sensitization of DRG neurons and the pathogenesis of BCP in rats. These findings uncover a potentially targetable mechanism contributing to bone metastasis-associated pain in cancer patients.
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Neoplasias Óseas , Dolor en Cáncer , Receptores ErbB , Ganglios Espinales , Histona Desacetilasa 2 , Canal de Potasio KCNQ2 , Animales , Histona Desacetilasa 2/metabolismo , Histona Desacetilasa 2/genética , Canal de Potasio KCNQ2/genética , Canal de Potasio KCNQ2/metabolismo , Ganglios Espinales/metabolismo , Ganglios Espinales/patología , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Neoplasias Óseas/secundario , Neoplasias Óseas/patología , Ratas , Dolor en Cáncer/genética , Dolor en Cáncer/metabolismo , Dolor en Cáncer/patología , Receptores ErbB/metabolismo , Receptores ErbB/genética , Canal de Potasio KCNQ3/genética , Canal de Potasio KCNQ3/metabolismo , Transcripción Genética , Proteína 2 de Unión a Metil-CpG/genética , Proteína 2 de Unión a Metil-CpG/metabolismo , Complejo Correpresor Histona Desacetilasa y Sin3/genética , Transducción de Señal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Humanos , Femenino , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Ratas Sprague-Dawley , Sistema de Señalización de MAP Quinasas/genéticaRESUMEN
TORC1 (target of rapamycin complex 1) is a highly conserved protein kinase that plays a central role in regulating cell growth. Given the role of mammalian TORC1 (mTORC1) in metabolism and disease, understanding mTORC1 downstream signaling and feedback loops is important. mTORC1 recognizes some of its substrates via a five amino acid binding sequence called the TOR signaling (TOS) motif. mTORC1 binding to a TOS motif facilitates phosphorylation of a distinct, distal site. Here, we show that LST2, also known as ZFYVE28, contains a TOS motif (amino acids 401 to 405) and is directly phosphorylated by mTORC1 at serine 670 (S670). mTORC1-mediated S670 phosphorylation promotes LST2 monoubiquitination on lysine 87 (K87). Monoubiquitinated LST2 is stable and displays a broad reticular distribution. When mTORC1 is inactive, unphosphorylated LST2 is degraded by the proteasome. The absence of LST2 enhances EGFR (epidermal growth factor receptor) signaling. We propose that mTORC1 negatively feeds back on its upstream receptor EGFR via LST2.
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Receptores ErbB , Diana Mecanicista del Complejo 1 de la Rapamicina , Transducción de Señal , Ubiquitinación , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Fosforilación , Humanos , Receptores ErbB/metabolismo , Células HEK293 , Animales , Secuencias de AminoácidosRESUMEN
In EGFR-mutated lung cancer, the duration of response to tyrosine kinase inhibitors (TKIs) is limited by the development of acquired drug resistance. Despite the crucial role played by apoptosis-related genes in tumor cell survival, how their expression changes as resistance to EGFR-TKIs emerges remains unclear. Here, we conduct a comprehensive analysis of apoptosis-related genes, including BCL-2 and IAP family members, using single-cell RNA sequence (scRNA-seq) and spatial transcriptomics (ST). scRNA-seq of EGFR-mutated lung cancer cell lines captures changes in apoptosis-related gene expression following EGFR-TKI treatment, most notably BCL2L1 upregulation. scRNA-seq of EGFR-mutated lung cancer patient samples also reveals high BCL2L1 expression, specifically in tumor cells, while MCL1 expression is lower in tumors compared to non-tumor cells. ST analysis of specimens from transgenic mice with EGFR-driven lung cancer indicates spatial heterogeneity of tumors and corroborates scRNA-seq findings. Genetic ablation and pharmacological inhibition of BCL2L1/BCL-XL overcome or delay EGFR-TKI resistance. Overall, our findings indicate that BCL2L1/BCL-XL expression is important for tumor cell survival as EGFR-TKI resistance emerges.