RESUMEN
BACKGROUND: Variations in untranslated regions (UTR) alter regulatory pathways impacting phenotype, disease onset, and course of disease. Protein kinase C Zeta (PRKCZ), a serine-threonine kinase, is implicated in cardiovascular, neurological and oncological disorders. Due to limited research on PRKCZ, this study aimed to investigate the impact of UTR genetic variants' on binding sites for transcription factors and miRNA. RNA secondary structure, eQTLs, and variation tolerance analysis were also part of the study. METHODS: The data related to PRKCZ gene variants was downloaded from the Ensembl genome browser, COSMIC and gnomAD. The RegulomeDB database was used to assess the functional impact of 5' UTR and 3'UTR variants. The analysis of the transcription binding sites (TFBS) was done through the Alibaba tool, and the Kyoto Encyclopaedia of Genes and Genomes (KEGG) was employed to identify pathways associated with PRKCZ. To predict the effect of variants on microRNA binding sites, PolymiRTS was utilized for 3' UTR variants, and the SNPinfo tool was used for 5' UTR variants. RESULTS: The results obtained indicated that a total of 24 variants present in the 3' UTR and 25 variants present in the 5' UTR were most detrimental. TFBS analysis revealed that 5' UTR variants added YY1, repressor, and Oct1, whereas 3' UTR variants added AP-2alpha, AhR, Da, GR, and USF binding sites. The study predicted TFs that influenced PRKCZ expression. RNA secondary structure analysis showed that eight 5' UTR and six 3' UTR altered the RNA structure by either removal or addition of the stem-loop. The microRNA binding site analysis highlighted that seven 3' UTR and one 5' UTR variant altered the conserved site and also created new binding sites. eQTLs analysis showed that one variant was associated with PRKCZ expression in the lung and thyroid. The variation tolerance analysis revealed that PRKCZ was an intolerant gene. CONCLUSION: This study laid the groundwork for future studies aimed at targeting PRKCZ as a therapeutic target.
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Regiones no Traducidas 3' , MicroARNs , Proteína Quinasa C , ARN Mensajero , Humanos , Regiones no Traducidas 3'/genética , Regiones no Traducidas 5'/genética , Sitios de Unión , MicroARNs/genética , Conformación de Ácido Nucleico , Polimorfismo de Nucleótido Simple , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Estabilidad del ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Regiones no Traducidas/genéticaRESUMEN
BACKGROUND: Epithelial ovarian cancer, especially high grade serous ovarian cancer (HGSOC) is by far, the most lethal gynecological malignancy with poor prognosis and high relapse rate. Despite of availability of several therapeutic interventions including poly-ADP ribose polymerase (PARP) inhibitors, HGSOC remains unmanageable and identification of early detection biomarkers and therapeutic targets for this lethal malady is highly warranted. Aberrant expression of protein kinase C iota (PKCί) is implicated in many cellular and physiological functions involved in tumorigenesis including cell proliferation and cell cycle deregulation. METHODS AND RESULTS: Two high grade serous ovarian cancer cells SKOV3 and COV362 were employed in this study. PKCί was genetically knocked down or pharmacologically inhibited and several functional and biochemical assays were performed. We report that PKCί is overexpressed in HGSOC cells and patient tissue samples with a significant prognostic value. Pharmacological inhibition of PKCί by Na-aurothiomalate or its shRNA-mediated genetic knockdown suppressed HGSOC cell proliferation, EMT and induced apoptosis. Moreover, PKCί positively regulated GLUT1 and several other glycolytic genes including HK1, HK2, PGK1, ENO1 and LDHA to promote elevated glucose uptake and glycolysis in HGSOC cells. Mechanistically, PKCί drove glycolysis via PI3K/AKT/mTOR signalling. Na-aurothiomalate and highly selective, dual PI3K/mTOR inhibitor dactolisib could serve as novel anti-glycolytic drugs in HGSOC. CONCLUSION: Taken together, our results indicate PKCί/PI3K/AKT/mTOR signalling cascade could be a novel therapeutic target in a lethal pathology like HGSOC.
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Proliferación Celular , Glucólisis , Isoenzimas , Neoplasias Ováricas , Fosfatidilinositol 3-Quinasas , Proteína Quinasa C , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Humanos , Femenino , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Línea Celular Tumoral , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proliferación Celular/genética , Isoenzimas/metabolismo , Isoenzimas/genética , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patología , Apoptosis/genética , Regulación Neoplásica de la Expresión Génica , Carcinoma Epitelial de Ovario/metabolismo , Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/patología , PronósticoRESUMEN
Chronic fibrotic tissue disrupts various organ functions. Despite significant advances in therapies, mortality and morbidity due to heart failure remain high, resulting in poor quality of life. Beyond the cardiomyocyte-centric view of heart failure, it is now accepted that alterations in the interstitial extracellular matrix (ECM) also play a major role in the development of heart failure. Here, we show that protein kinase N (PKN) is expressed in cardiac fibroblasts. Furthermore, PKN mediates the conversion of fibroblasts into myofibroblasts, which plays a central role in secreting large amounts of ECM proteins via p38 phosphorylation signaling. Fibroblast-specific deletion of PKN led to a reduction of myocardial fibrotic changes and cardiac dysfunction in mice models of ischemia-reperfusion or heart failure with preserved ejection fraction. Our results indicate that PKN is a therapeutic target for cardiac fibrosis in heart failure.
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Fibroblastos , Fibrosis , Insuficiencia Cardíaca , Miocardio , Miofibroblastos , Proteína Quinasa C , Animales , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/genética , Miofibroblastos/metabolismo , Miofibroblastos/patología , Fibroblastos/metabolismo , Fibroblastos/patología , Ratones , Miocardio/patología , Miocardio/metabolismo , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Masculino , Humanos , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Ratones Noqueados , Matriz Extracelular/metabolismo , Fosforilación , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Transducción de SeñalRESUMEN
Obesity causes a range of tissue dysfunctions that increases the risk for morbidity and mortality. Protein kinase D (PKD) represents a family of stress-activated intracellular signalling proteins that regulate essential processes such as cell proliferation and differentiation, cell survival, and exocytosis. Evidence suggests that PKD regulates the cellular adaptations to the obese environment in metabolically important tissues and drives the development of a variety of diseases. This review explores the role that PKD plays in tissue dysfunction in obesity, with special consideration of the development of obesity-mediated cardiomyopathy, a distinct cardiovascular disease that occurs in the absence of common comorbidities and leads to eventual heart failure and death. The downstream mechanisms mediated by PKD that could contribute to dysfunctions observed in the heart and other metabolically important tissues in obesity, and the predicted cell types involved are discussed to suggest potential targets for the development of therapeutics against obesity-related disease.
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Obesidad , Proteína Quinasa C , Humanos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Obesidad/metabolismo , Obesidad/patología , Obesidad/genética , Animales , Miocardio/metabolismo , Miocardio/patología , Transducción de Señal , Cardiomiopatías/metabolismo , Cardiomiopatías/genética , Cardiomiopatías/patologíaRESUMEN
Protein kinase D (PKD) is a family of serine/threonine kinases that play important roles in various signalling pathways in cells, including neuronal cells. In the nervous system, PKD has been shown to be involved in learning and memory formation by regulating neurotransmitter release, neurite outgrowth and dendrite development, synapse formation and synaptic plasticity. In addition, PKD has been implicated in pain perception or neuroprotection during oxidative stress. Dysregulation of PKD expression and activity has been linked to several neurological disorders, including autism and epilepsy. In this review, we summarize the current knowledge on the function of the PKD family members in neuronal cells, including the spatial regulation of their downstream signalling pathways. We will further discuss the potential role of PKD in the pathogenesis of neurological disorders.
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Neuronas , Proteína Quinasa C , Transducción de Señal , Humanos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Neuronas/metabolismo , Animales , Plasticidad NeuronalRESUMEN
The PKC-related kinases (PRKs, also termed PKNs) are important in cell migration, cancer, hepatitis C infection, and nutrient sensing. They belong to a group of protein kinases called AGC kinases that share common features like a C-terminal extension to the catalytic domain comprising a hydrophobic motif. PRKs are regulated by N-terminal domains, a pseudosubstrate sequence, Rho-binding domains, and a C2 domain involved in inhibition and dimerization, while Rho and lipids are activators. We investigated the allosteric regulation of PRK2 and its interaction with its upstream kinase PDK1 using a chemical biology approach. We confirmed the phosphoinositide-dependent protein kinase 1 (PDK1)-interacting fragment (PIF)-mediated docking interaction of PRK2 with PDK1 and showed that this interaction can be modulated allosterically. We showed that the polypeptide PIFtide and a small compound binding to the PIF-pocket of PRK2 were allosteric activators, by displacing the pseudosubstrate PKL region from the active site. In addition, a small compound binding to the PIF-pocket allosterically inhibited the catalytic activity of PRK2. Together, we confirmed the docking interaction and allostery between PRK2 and PDK1 and described an allosteric communication between the PIF-pocket and the active site of PRK2, both modulating the conformation of the ATP-binding site and the pseudosubstrate PKL-binding site. Our study highlights the allosteric modulation of the activity and the conformation of PRK2 in addition to the existence of at least two different complexes between PRK2 and its upstream kinase PDK1. Finally, the study highlights the potential for developing allosteric drugs to modulate PRK2 kinase conformations and catalytic activity.
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Proteína Quinasa C , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Humanos , Regulación Alostérica , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Proteína Quinasa C/química , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , Dominio Catalítico , Simulación del Acoplamiento Molecular , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/química , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/genética , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/química , Unión ProteicaRESUMEN
BACKGROUND: Diabetes mellitus (DM) affects up to one-third of breast cancer (BC) patients. Patients with co-existing BC and DM (BC-DM) have worsened BC prognosis. Nevertheless, the molecular mechanisms orchestrating BC-DM prognosis remain poorly understood. tRNA-derived fragments (tRFs) have been shown to regulate cancer progression. However, the biological role of tRFs in BC-DM has not been explored. METHODS: tRF levels in tumor tissues and cells were detected by tRF sequencing and qRT-PCR. The effects of tRF on BC cell malignancy were assessed under euglycemic and hyperglycemic conditions in vitro. Metabolic changes were assessed by lactate, pyruvate, and extracellular acidification rate (ECAR) assays. Diabetic animal model was used to evaluate the impacts of tRF on BC tumor growth. RNA-sequencing (RNA-seq), qRT-PCR, Western blot, polysome profiling, luciferase reporter assay, and rescue experiments were performed to explore the regulatory mechanisms of tRF in BC-DM. RESULTS: We identified that tRF-Cys-GCA-029 was downregulated in BC-DM tissues and under hyperglycemia conditions in BC cells. Functionally, downregulation of tRF-Cys-GCA-029 promoted BC cell proliferation and migration in a glucose level-dependent manner. tRF-Cys-GCA-029 knockdown also enhanced glycolysis metabolism in BC cells, indicated by increasing lactate/pyruvate production and ECAR levels. Notably, injection of tRF-Cys-GCA-029 mimic significantly suppressed BC tumor growth in diabetic-mice. Mechanistically, tRF-Cys-GCA-029 regulated BC cell malignancy and glycolysis via interacting with PRKCG in two ways: binding to the coding sequence (CDS) of PRKCG mRNA to regulate its transcription and altering polysomal PRKCG mRNA expression to modify its translation. CONCLUSIONS: Hyperglycemia-downregulated tRF-Cys-GCA-029 enhances the malignancy and glycolysis of BC cells. tRF-Cys-GCA-029-PRKCG-glycolysis axis may be a potential therapeutic target against BC-DM.
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Neoplasias de la Mama , Regulación Neoplásica de la Expresión Génica , Glucólisis , Hiperglucemia , Humanos , Femenino , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Hiperglucemia/metabolismo , Hiperglucemia/genética , Ratones , Proliferación Celular , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Línea Celular Tumoral , Carcinogénesis/genética , Regulación hacia Abajo , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Regulación hacia Arriba , PronósticoRESUMEN
The Pcdhg gene cluster encodes 22 γ-Protocadherin (γ-Pcdh) cell adhesion molecules that critically regulate multiple aspects of neural development, including neuronal survival, dendritic and axonal arborization, and synapse formation and maturation. Each γ-Pcdh isoform has unique protein domains-a homophilically interacting extracellular domain and a juxtamembrane cytoplasmic domain-as well as a C-terminal cytoplasmic domain shared by all isoforms. The extent to which isoform-specific versus shared domains regulate distinct γ-Pcdh functions remains incompletely understood. Our previous in vitro studies identified protein kinase C (PKC) phosphorylation of a serine residue within a shared C-terminal motif as a mechanism through which γ-Pcdh promotion of dendrite arborization via myristoylated alanine-rich C-kinase substrate (MARCKS) is abrogated. Here, we used CRISPR/Cas9 genome editing to generate two new mouse lines expressing only non-phosphorylatable γ-Pcdhs, due either to a serine-to-alanine mutation (PcdhgS/A) or to a 15-amino acid C-terminal deletion resulting from insertion of an early stop codon (PcdhgCTD). Both lines are viable and fertile, and the density and maturation of dendritic spines remain unchanged in both PcdhgS/A and PcdhgCTD cortex. Dendrite arborization of cortical pyramidal neurons, however, is significantly increased in both lines, as are levels of active MARCKS. Intriguingly, despite having significantly reduced levels of γ-Pcdh proteins, the PcdhgCTD mutation yields the strongest phenotype, with even heterozygous mutants exhibiting increased arborization. The present study confirms that phosphorylation of a shared C-terminal motif is a key γ-Pcdh negative regulation point and contributes to a converging understanding of γ-Pcdh family function in which distinct roles are played by both individual isoforms and discrete protein domains.
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Proteínas Relacionadas con las Cadherinas , Cadherinas , Corteza Cerebral , Dendritas , Proteína Quinasa C , Animales , Corteza Cerebral/metabolismo , Corteza Cerebral/citología , Cadherinas/metabolismo , Cadherinas/genética , Fosforilación/fisiología , Dendritas/metabolismo , Ratones , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Sustrato de la Proteína Quinasa C Rico en Alanina Miristoilada/metabolismo , Sustrato de la Proteína Quinasa C Rico en Alanina Miristoilada/genética , Secuencias de Aminoácidos/fisiología , Ratones TransgénicosRESUMEN
How can short-lived molecules selectively maintain the potentiation of activated synapses to sustain long-term memory? Here, we find kidney and brain expressed adaptor protein (KIBRA), a postsynaptic scaffolding protein genetically linked to human memory performance, complexes with protein kinase Mzeta (PKMζ), anchoring the kinase's potentiating action to maintain late-phase long-term potentiation (late-LTP) at activated synapses. Two structurally distinct antagonists of KIBRA-PKMζ dimerization disrupt established late-LTP and long-term spatial memory, yet neither measurably affects basal synaptic transmission. Neither antagonist affects PKMζ-independent LTP or memory that are maintained by compensating PKCs in ζ-knockout mice; thus, both agents require PKMζ for their effect. KIBRA-PKMζ complexes maintain 1-month-old memory despite PKMζ turnover. Therefore, it is not PKMζ alone, nor KIBRA alone, but the continual interaction between the two that maintains late-LTP and long-term memory.
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Péptidos y Proteínas de Señalización Intracelular , Potenciación a Largo Plazo , Ratones Noqueados , Proteína Quinasa C , Animales , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Ratones , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Memoria/fisiología , Memoria a Largo Plazo/fisiología , Sinapsis/metabolismo , Sinapsis/fisiología , Unión Proteica , FosfoproteínasAsunto(s)
Medicina de Precisión , Inhibidores de Proteínas Quinasas , Humanos , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Proteína Quinasa C/genética , Proteína Quinasa C/antagonistas & inhibidores , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Reposicionamiento de Medicamentos , Malformaciones Vasculares/tratamiento farmacológico , Malformaciones Vasculares/genética , Malformaciones Vasculares/patologíaRESUMEN
The voltage-gated Kv1.5 potassium channel, conducting the ultra-rapid delayed rectifier K+ current (IKur) in human cells, plays important roles in the repolarization of atrial action potentials and regulation of the vascular tone. We previously reported that activation of protein kinase C (PKC) by phorbol 12-myristate 13-acetate (PMA) induces endocytic degradation of cell-surface Kv1.5 channels, and a point mutation removing the phosphorylation site, T15A, in the N terminus of Kv1.5 abolished the PMA-effect. In the present study, using mutagenesis, patch clamp recording, Western blot analysis, and immunocytochemical staining, we demonstrate that ubiquitination is involved in the PMA-mediated degradation of mature Kv1.5 channels. Since the expression of the Kv1.4 channel is unaffected by PMA treatment, we swapped the N- and/or C-termini between Kv1.5 and Kv1.4. We found that the N-terminus alone did not but both N- and C-termini of Kv1.5 did confer PMA sensitivity to mature Kv1.4 channels, suggesting the involvement of Kv1.5 C-terminus in the channel ubiquitination. Removal of each of the potential ubiquitination residue Lysine at position 536, 565, and 591 by Arginine substitution (K536R, K565R, and K591R) had little effect, but removal of all three Lysine residues with Arginine substitution (3K-R) partially reduced PMA-mediated Kv1.5 degradation. Furthermore, removing the cysteine residue at position 604 by Serine substitution (C604S) drastically reduced PMA-induced channel degradation. Removal of the three Lysines and Cys604 with a quadruple mutation (3K-R/C604S) or a truncation mutation (Δ536) completely abolished the PKC activation-mediated degradation of Kv1.5 channels. These results provide mechanistic insight into PKC activation-mediated Kv1.5 degradation.
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Canal de Potasio Kv1.5 , Proteína Quinasa C , Proteolisis , Acetato de Tetradecanoilforbol , Ubiquitinación , Canal de Potasio Kv1.5/metabolismo , Canal de Potasio Kv1.5/genética , Humanos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Acetato de Tetradecanoilforbol/farmacología , Células HEK293 , Animales , Fosforilación , Membrana Celular/metabolismo , Canal de Potasio Kv1.4/metabolismo , Canal de Potasio Kv1.4/genéticaRESUMEN
Members of the Protein kinases D (PKD) family are described as regulators of T cell responses. From the two T cell-expressed isoforms PKD2 and PKD3, so far mainly the former was thoroughly investigated and is well understood. Recently, we have investigated also PKD3 using conventional as well as conditional T cell-specific knockout models. These studies suggested PKD3 to be a T cell-extrinsic regulator of the cells' fate. However, these former model systems did not take into account possible redundancies with the highly homologous PKD2. To overcome this issue and thus properly unravel PKD3's T cell-intrinsic functions, here we additionally used a mouse model overexpressing a constitutively active isoform of PKD3 specifically in the T cell compartment. These transgenic mice showed a slightly higher proportion of central memory T cells in secondary lymphoid organs and blood. This effect could not be explained via differences upon polyclonal stimulation in vitro, however, may be connected to the observed developmental aberrances in the CD8 single positive compartment during thymic development. Lastly, the observed alterations in the CD8+ T cell compartment did not impact proper immune response upon immunization with ovalbumin or in a subcutaneous tumour model suggesting only a small to absent biological relevance. Taking together the knowledge of all our published studies on PKD3 in the T cell compartment, we now conclude that T cell-intrinsic PKD3 is a fine-tuner of central memory T cell as well as CD8 single positive thymocyte development.
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Linfocitos T CD8-positivos , Diferenciación Celular , Células T de Memoria , Proteína Quinasa C , Timocitos , Animales , Ratones , Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Timocitos/inmunología , Timocitos/metabolismoRESUMEN
The Ca2+-independent, but diacylglycerol-regulated, novel protein kinase C (PKC) theta (θ) is highly expressed in hematopoietic cells where it participates in immune signaling and platelet function. Mounting evidence suggests that PKCθ may be involved in cancer, particularly blood cancers, breast cancer, and gastrointestinal stromal tumors, yet how to target this kinase (as an oncogene or as a tumor suppressor) has not been established. Here, we examine the effect of four cancer-associated mutations, R145H/C in the autoinhibitory pseudosubstrate, E161K in the regulatory C1A domain, and R635W in the regulatory C-terminal tail, on the cellular activity and stability of PKCθ. Live-cell imaging studies using the genetically-encoded fluorescence resonance energy transfer-based reporter for PKC activity, C kinase activity reporter 2 (CKAR2), revealed that the pseudosubstrate and C1A domain mutations impaired autoinhibition to increase basal signaling. This impaired autoinhibition resulted in decreased stability of the protein, consistent with the well-characterized behavior of Ca2+-regulated PKC isozymes wherein mutations that impair autoinhibition are paradoxically loss-of-function because the mutant protein is degraded. In marked contrast, the C-terminal tail mutation resulted in enhanced autoinhibition and enhanced stability. Thus, the examined mutations were loss-of-function by different mechanisms: mutations that impaired autoinhibition promoted the degradation of PKC, and those that enhanced autoinhibition stabilized an inactive PKC. Supporting a general loss-of-function of PKCθ in cancer, bioinformatics analysis revealed that protein levels of PKCθ are reduced in diverse cancers, including lung, renal, head and neck, and pancreatic. Our results reveal that PKCθ function is lost in cancer.
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Neoplasias , Proteína Quinasa C-theta , Humanos , Proteína Quinasa C-theta/genética , Proteína Quinasa C-theta/metabolismo , Proteína Quinasa C-theta/química , Neoplasias/genética , Neoplasias/enzimología , Neoplasias/metabolismo , Mutación con Pérdida de Función , Células HEK293 , Dominios Proteicos , Mutación , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Proteína Quinasa C/químicaRESUMEN
The early mechanisms of spontaneous tumor initiation that precede malignancy are largely unknown. We show that reduced aPKC levels correlate with stem cell loss and the induction of revival and metaplastic programs in serrated- and conventional-initiated premalignant lesions, which is perpetuated in colorectal cancers (CRCs). Acute inactivation of PKCλ/ι in vivo and in mouse organoids is sufficient to stimulate JNK in non-transformed intestinal epithelial cells (IECs), which promotes cell death and the rapid loss of the intestinal stem cells (ISCs), including those that are LGR5+. This is followed by the accumulation of revival stem cells (RSCs) at the bottom of the crypt and fetal-metaplastic cells (FMCs) at the top, creating two spatiotemporally distinct cell populations that depend on JNK-induced AP-1 and YAP. These cell lineage changes are maintained during cancer initiation and progression and determine the aggressive phenotype of human CRC, irrespective of their serrated or conventional origin.
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Neoplasias Colorrectales , Células Epiteliales , Metaplasia , Proteína Quinasa C , Animales , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/genética , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Metaplasia/patología , Metaplasia/metabolismo , Ratones , Humanos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Células Madre/metabolismo , Células Madre/patología , Factor de Transcripción AP-1/metabolismo , Factor de Transcripción AP-1/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Proteínas Señalizadoras YAP/metabolismo , Transformación Celular Neoplásica/patología , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/deficiencia , Organoides/metabolismo , Organoides/patología , Linaje de la Célula , Isoenzimas/metabolismo , Isoenzimas/genética , Isoenzimas/deficiencia , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/metabolismoRESUMEN
BACKGROUND AND AIMS: PKC-fused blue naevi are a recently described group of melanocytic tumours that have distinctive morphological features, including a pigmented epithelioid melanocytoma-like junctional component or a dermal biphasic architecture associating with naevocytoid nests surrounded by dendritic and spindled pigmented melanocytes (so-called 'combined common and blue naevus'). There have been reports of smooth muscle hyperplasia in a hamartoma-like pattern in cases of combined blue naevi without genetic exploration. MATERIALS AND METHODS: Herein, we describe 12 cases of protein kinase C (PKC)-fused blue tumours associated with a co-existing smooth muscle hyperplasia, identified from a total of 98 PKC-fused melanocytic tumours. Archived slides of PKC-fused blue naevi with haematoxylin, eosin and phloxin staining, immunohistochemistry and molecular confirmation of a PKC-fusion by fluorescence in-situ hybridisation (FISH) or RNAseq were re-evaluated for identification of notable smooth muscle hyperplasia. Fifty-one of these slides had already been studied in a previous publication from our group. RESULTS: The hyperplasia ranged from hypertrophic arrector pili muscles to extensive horizontal bundles of disorganised fibres constantly associated and limited within a biphasic dermal melanocytic component. At least one arrector pili muscle was always visible within the tumour, with occasionally direct extension of the hyperplastic fibres from the main muscle body. These muscle fibres were devoid of a PKC-fusion signal by FISH. PKC molecules are involved in the regulation of smooth muscle function, offering an explanatory framework. CONCLUSIONS: These data suggest incorporating smooth muscle hyperplasia as a diagnostic morphological feature of PKC-fused blue melanocytic tumours.
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Hiperplasia , Músculo Liso , Nevo Azul , Proteína Quinasa C , Neoplasias Cutáneas , Humanos , Hiperplasia/patología , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Femenino , Masculino , Adulto , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/genética , Nevo Azul/patología , Nevo Azul/genética , Nevo Azul/diagnóstico , Músculo Liso/patología , Persona de Mediana Edad , Adolescente , Adulto Joven , Niño , AncianoRESUMEN
The Ser/Thr kinase protein kinase-D1 (PKD1) is involved in induction of various cell physiological processes in the heart such as myocellular hypertrophy and inflammation, which may turn maladaptive during long-term stimulation. Of special interest is a key role of PKD1 in the regulation of cardiac substrate metabolism. Glucose and fatty acids are the most important substrates for cardiac energy provision, and the ratio at which they are utilized determines the health status of the heart. Cardiac glucose uptake is mainly regulated by translocation of the glucose transporter GLUT4 from intracellular stores (endosomes) to the sarcolemma, and fatty acid uptake via a parallel translocation of fatty acid transporter CD36 from endosomes to the sarcolemma. PKD1 is involved in the regulation of GLUT4 translocation, but not CD36 translocation, giving it the ability to modulate glucose uptake without affecting fatty acid uptake, thereby altering the cardiac substrate balance. PKD1 would therefore serve as an attractive target to combat cardiac metabolic diseases with a tilted substrate balance, such as diabetic cardiomyopathy. However, PKD1 activation also elicits cardiac hypertrophy and inflammation. Therefore, identification of the events upstream and downstream of PKD1 may provide superior therapeutic targets to alter the cardiac substrate balance. Recent studies have identified the lipid kinase phosphatidylinositol 4-kinase IIIß (PI4KIIIß) as signaling hub downstream of PKD1 to selectively stimulate GLUT4-mediated myocardial glucose uptake without inducing hypertrophy. Taken together, the PKD1 signaling pathway serves a pivotal role in cardiac glucose metabolism and is a promising target to selectively modulate glucose uptake in cardiac disease.
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Transportador de Glucosa de Tipo 4 , Glucosa , Miocardio , Proteína Quinasa C , Transporte de Proteínas , Transducción de Señal , Transportador de Glucosa de Tipo 4/metabolismo , Humanos , Miocardio/metabolismo , Animales , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Glucosa/metabolismo , Antígenos CD36/metabolismo , Antígenos CD36/genética , Ácidos Grasos/metabolismoRESUMEN
Cribriform adenocarcinoma of the salivary gland (CASG) is an entity that is currently classified under polymorphous adenocarcinoma (PAC), cribriform subtype per the 2022 WHO classification of head and neck tumours. There is debate about whether CASG should be considered a separate diagnostic entity, as CASG differs from conventional PAC in anatomic site, clinical behaviors, and molecular patterns. Herein we describe a challenging and unique case which shares histologic and behavioral features between CASG and conventional PAC with a YLPM1::PRKD1 rearrangement not previously reported in the literature.
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Adenocarcinoma , Proteínas de Fusión Oncogénica , Neoplasias de las Glándulas Salivales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adenocarcinoma/genética , Adenocarcinoma/patología , Fusión Génica , Proteínas de Fusión Oncogénica/genética , Proteína Quinasa C/genética , Neoplasias de las Glándulas Salivales/genética , Neoplasias de las Glándulas Salivales/patología , Proteínas de Unión al ARN/genética , Proteínas Represoras/genéticaRESUMEN
BACKGROUND: Hypothermic ischemia-reperfusion arrhythmia is a common complication of cardiothoracic surgery under cardiopulmonary bypass, but few studies have focused on this type of arrhythmia. Our prior study discovered reduced myocardial Cx43 protein levels may be linked to hypothermic reperfusion arrhythmias. However, more detailed molecular mechanism research is required. METHOD: The microRNA and mRNA expression levels in myocardial tissues were detected by real-time quantitative PCR (RT-qPCR). Besides, the occurrence of hypothermic reperfusion arrhythmias and changes in myocardial electrical conduction were assessed by electrocardiography and ventricular epicardial activation mapping. Furthermore, bioinformatics analysis, applying antagonists of miRNA, western blotting, immunohistochemistry, a dual luciferase assay, and pearson correlation analysis were performed to investigate the underlying molecular mechanisms. RESULTS: The expression level of novel-miR-17 was up-regulated in hypothermic ischemia-reperfusion myocardial tissues. Inhibition of novel-miR-17 upregulation ameliorated cardiomyocyte edema, reduced apoptosis, increased myocardial electrical conduction velocity, and shortened the duration of reperfusion arrhythmias. Mechanistic studies showed that novel-miR-17 reduced the expression of Cx43 by directly targeting Gja1 while mediating the activation of the PKC/c-Jun signaling pathway. CONCLUSION: Up-regulated novel-miR-17 is a newly discovered pro-arrhythmic microRNA that may serve as a potential therapeutic target and biomarker for hypothermic reperfusion arrhythmias.
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Arritmias Cardíacas , Conexina 43 , MicroARNs , Proteína Quinasa C , Transducción de Señal , Animales , Humanos , Masculino , Ratas , Apoptosis/genética , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/genética , Arritmias Cardíacas/etiología , Arritmias Cardíacas/patología , Conexina 43/metabolismo , Conexina 43/genética , MicroARNs/genética , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/etiología , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Proteína Quinasa C/metabolismo , Proteína Quinasa C/genética , Proteínas Proto-Oncogénicas c-jun/metabolismo , Regulación hacia ArribaRESUMEN
Regulated hydrolysis of the phosphoinositide phosphatidylinositol(4,5)-bis-phosphate to diacylglycerol and inositol-1,4,5-P3 defines a major eukaryotic pathway for translation of extracellular cues to intracellular signaling circuits. Members of the lipid-activated protein kinase C isoenzyme family (PKCs) play central roles in this signaling circuit. One of the regulatory mechanisms employed to downregulate stimulated PKC activity is via a proteasome-dependent degradation pathway that is potentiated by peptidyl-prolyl isomerase Pin1. Here, we show that contrary to prevailing models, Pin1 does not regulate conventional PKC isoforms α and ßII via a canonical cis-trans isomerization of the peptidyl-prolyl bond. Rather, Pin1 acts as a PKC binding partner that controls PKC activity via sequestration of the C-terminal tail of the kinase. The high-resolution structure of full-length Pin1 complexed to the C-terminal tail of PKCßII reveals that a novel bivalent interaction mode underlies the non-catalytic mode of Pin1 action. Specifically, Pin1 adopts a conformation in which it uses the WW and PPIase domains to engage two conserved phosphorylated PKC motifs, the turn motif and hydrophobic motif, respectively. Hydrophobic motif is a non-canonical Pin1-interacting element. The structural information combined with the results of extensive binding studies and experiments in cultured cells suggest that non-catalytic mechanisms represent unappreciated modes of Pin1-mediated regulation of AGC kinases and other key enzymes/substrates.
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Peptidilprolil Isomerasa de Interacción con NIMA , Unión Proteica , Peptidilprolil Isomerasa de Interacción con NIMA/metabolismo , Peptidilprolil Isomerasa de Interacción con NIMA/química , Peptidilprolil Isomerasa de Interacción con NIMA/genética , Humanos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/química , Proteína Quinasa C/genética , Conformación ProteicaRESUMEN
The latex of Euphorbia peplus and its major component 20-deoxyingenol-3-angelate (DI3A) displayed significant nematicidal activity against Caenorhabditis elegans and Panagrellus redivivus. DI3A treatment inhibited the growth and development of nematodes and caused significantly negative effects on locomotion behavior, reproduction, and accumulation of reactive oxygen species. Transcriptome analysis indicated that differential expression genes in DI3A-treated C. elegans were mainly associated with the metabolism, growth, and development process, which were further confirmed by RT-qPCR experiments. The expression level of TPA-1 gene encoding a protein kinase C isotype was obviously upregulated by DI3A treatment, and knockdown of TPA-1 by RNAi technology in the nematode could relieve the growth-inhibitory effect of DI3A. Metabolic analysis indicated that DI3A was hardly metabolized by C. elegans, but a glycosylated indole derivative was specifically accumulated likely due to the activation of detoxification. Overall, our findings suggested that DI3A from E. peplus latex exerted a potent nematicidal effect through the gene TPA-1, which provides a potential target for the control of nematodes and also suggests the potential application value of E. peplus latex and DI3A as botanical nematicides.