RESUMEN
The dorsal and ventral human telencephalons contain different neuronal subtypes, including glutamatergic, GABAergic, and cholinergic neurons, and how these neurons are generated during early development is not well understood. Using scRNA-seq and stringent validations, we reveal here a developmental roadmap for human telencephalic neurons. Both dorsal and ventral telencephalic radial glial cells (RGs) differentiate into neurons via dividing intermediate progenitor cells (IPCs_div) and early postmitotic neuroblasts (eNBs). The transcription factor ASCL1 plays a key role in promoting fate transition from RGs to IPCs_div in both regions. RGs from the regionalized neuroectoderm show heterogeneity, with restricted glutamatergic, GABAergic, and cholinergic differentiation potencies. During neurogenesis, IPCs_div gradually exit the cell cycle and branch into sister eNBs to generate distinct neuronal subtypes. Our findings highlight a general RGs-IPCs_div-eNBs developmental scheme for human telencephalic progenitors and support that the major neuronal fates of human telencephalon are predetermined during dorsoventral regionalization with neuronal diversity being further shaped during neurogenesis and neural circuit integration.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Linaje de la Célula/genética , Regulación del Desarrollo de la Expresión Génica , Neurogénesis/genética , Neuronas/metabolismo , Telencéfalo/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Ciclo Celular/genética , Diferenciación Celular , Colina/metabolismo , Proteína Doblecortina/genética , Proteína Doblecortina/metabolismo , Feto , Ontología de Genes , Glutamato Descarboxilasa/genética , Glutamato Descarboxilasa/metabolismo , Ácido Glutámico/metabolismo , Humanos , Proteínas con Homeodominio LIM/genética , Proteínas con Homeodominio LIM/metabolismo , Anotación de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neuroglía/citología , Neuroglía/metabolismo , Neuronas/clasificación , Neuronas/citología , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo , Transducción de Señal , Estatmina/genética , Estatmina/metabolismo , Telencéfalo/citología , Telencéfalo/crecimiento & desarrollo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Proper microtubule dynamics are critical for neuronal morphogenesis and functions, and their dysregulation results in neurological disorders and regeneration failure. Superior cervical ganglion-10 (SCG10, also known as stathmin-2 or STMN2) is a well-known regulator of microtubule dynamics in neurons, but its functions in the peripheral nervous system remain largely unknown. Here, we show that Scg10 knockout mice exhibit severely progressive motor and sensory dysfunctions with significant sciatic nerve myelination deficits and neuromuscular degeneration. Additionally, increased microtubule stability, shown by a significant increase in tubulin acetylation and decrease in tubulin tyrosination, and decreased axonal transport were observed in Scg10 knockout dorsal root ganglion (DRG) neurons. Furthermore, SCG10 depletion impaired axon regeneration in both injured mouse sciatic nerve and cultured DRG neurons following replating, and the impaired axon regeneration was found to be induced by a lack of SCG10-mediated microtubule dynamics in the neurons. Thus, our results highlight the importance of SCG10 in peripheral axon maintenance and regeneration.
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Axones , Tubulina (Proteína) , Animales , Ratones , Axones/fisiología , Ganglios Espinales , Regeneración Nerviosa/genética , Neuronas , Estatmina/genéticaRESUMEN
Axon integrity is essential for functional connectivity in the nervous system. The degeneration of stressed or damaged axons is a common and sometimes initiating event in neurodegenerative disorders. Stathmin-2 (Stmn2) is an axon maintenance factor that is depleted in amyotrophic lateral sclerosis, and replenishment of Stmn2 can restore neurite outgrowth in diseased neurons. However, mechanisms responsible for Stmn2-mediated axon maintenance in injured neurons are not known. We used primary sensory neurons to interrogate the role of Stmn2 in the degeneration of severed axons. We discover that membrane association of Stmn2 is critical for its axon-protective activity. Structure-function studies revealed that axonal enrichment of Stmn2 is driven by palmitoylation as well as tubulin interaction. Using live imaging, we discover that another Stmn, Stmn3, comigrates with Stmn2-containing vesicles. We also demonstrate that Stmn3 undergoes regulated degradation through dual leucine zipper kinase (DLK)-c-Jun N-terminal kinase signaling. The Stmn2 membrane-targeting domain is both necessary and sufficient for localization to a specific vesicle population and confers sensitivity to DLK-dependent degradation. Our findings reveal a broader role for DLK in tuning the local abundance of palmitoylated Stmns in axon segments. Moreover, palmitoylation is a critical component of Stmn-mediated axon protection, and defining the Stmn2-containing vesicle population will provide important clues toward mechanisms of axon maintenance.
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Esclerosis Amiotrófica Lateral , Estatmina , Humanos , Estatmina/genética , Estatmina/metabolismo , Axones/metabolismo , Neuronas/metabolismo , Transducción de Señal , Esclerosis Amiotrófica Lateral/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismoRESUMEN
BACKGROUND: Upregulation of SMC1A (Structural maintenance of chromosomes 1A) is linked with many types of cancer and its oncogenic function, which has been associated with crucial cellular mechanisms (cell division, cell cycle checkpoints regulation and DNA repair). Recent studies have shown that SMC1A was involved in breast cancer, although the exact mechanisms of SMC1A remain to be determined. METHODS: Using The Cancer Genome Atlas (TCGA) database, we examined SMC1A expression and its relation to other genes, including FOXM1 and STMN1. Short hairpin RNA was used to subsequently examine the biological roles of SMC1A in MDA-MB-231 and MDA-MB-468 cell lines. Bioinformatics were performed to identify the SMC1A-related gene FOXM1. RESULTS: Here, we used the TCGA database to show that SMC1A is overexpressed in breast cancer. Later investigations showed SMC1A's role in breast cancer cell survival, apoptosis and invasion. Using bioinformatics and western blot assays, we confirmed that FOXM1 acted as the downstream of SMC1A, and SMC1A knockdown significantly downregulated the FOXM1 expression via the AKT signal pathway. Interestingly, the inhibition effects induced by SMC1A downregulation could be reversed by FOXM1 overexpression. In the clinic, SMC1A expression is favorably linked with FOXM1 expression in breast cancer tumor tissues. CONCLUSIONS: Collectively, our results not only enhance our knowledge of SMC1A's molecular pathways in breast cancer, but also suggest a potential new therapeutic target.
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Neoplasias de la Mama , Proteínas de Ciclo Celular , Proteínas Cromosómicas no Histona , Transducción de Señal , Femenino , Humanos , Neoplasias de la Mama/patología , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/genética , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Estatmina/genética , Proteínas Cromosómicas no Histona/genética , Proteínas de Ciclo Celular/genéticaRESUMEN
Nuclear clearance and cytoplasmic accumulations of the RNA-binding protein TDP-43 are pathological hallmarks in almost all patients with amyotrophic lateral sclerosis (ALS) and up to 50% of patients with frontotemporal dementia (FTD) and Alzheimer's disease. In Alzheimer's disease, TDP-43 pathology is predominantly observed in the limbic system and correlates with cognitive decline and reduced hippocampal volume. Disruption of nuclear TDP-43 function leads to abnormal RNA splicing and incorporation of erroneous cryptic exons in numerous transcripts including Stathmin-2 (STMN2, also known as SCG10) and UNC13A, recently reported in tissues from patients with ALS and FTD. Here, we identify both STMN2 and UNC13A cryptic exons in Alzheimer's disease patients, that correlate with TDP-43 pathology burden, but not with amyloid-ß or tau deposits. We also demonstrate that processing of the STMN2 pre-mRNA is more sensitive to TDP-43 loss of function than UNC13A. In addition, full-length RNAs encoding STMN2 and UNC13A are suppressed in large RNA-seq datasets generated from Alzheimer's disease post-mortem brain tissue. Collectively, these results open exciting new avenues to use STMN2 and UNC13A as potential therapeutic targets in a broad range of neurodegenerative conditions with TDP-43 proteinopathy including Alzheimer's disease.
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Enfermedad de Alzheimer , Esclerosis Amiotrófica Lateral , Demencia Frontotemporal , Enfermedad de Pick , Humanos , Enfermedad de Alzheimer/genética , Proteínas de Unión al ADN/genética , Empalme del ARN , ARN Mensajero/genética , Estatmina/genéticaRESUMEN
As part of the central nervous system (CNS), the retina senses light and also conducts and processes visual impulses. The damaged development of the retina not only causes visual damage, but also leads to epilepsy, dementia and other brain diseases. Recently, we have reported that copper (Cu) overload induces retinal developmental defects and down-regulates microtubule (MT) genes during zebrafish embryogenesis, but whether the down-regulation of microtubule genes mediates Cu stress induced retinal developmental defects is still unknown. In this study, we found that microtubule gene stmn4 exhibited obviously reduced expression in the retina of Cu overload embryos. Furthermore, stmn4 deficiency (stmn4-/-) resulted in retinal defects similar to those seen in Cu overload embryos, while overexpression of stmn4 effectively rescued retinal defects and cell apoptosis occurred in the Cu overload embryos and larvae. Meanwhile, stmn4 deficient embryos and larvae exhibited reduced mature retinal cells, the down-regulated expression of microtubules and cell cycle-related genes, and the mitotic cell cycle arrests of the retinal cells, which subsequently tended to apoptosis independent on p53. The results of this study demonstrate that Cu stress might lead to retinal developmental defects via down-regulating expression of microtubule gene stmn4, and stmn4 deficiency leads to impaired cell cycle and the accumulation of retinal progenitor cells (RPCs) and their subsequent apoptosis. The study provides a certain referee for copper overload in regulating the retinal development in fish.
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Cobre , Retina , Estatmina , Pez Cebra , Animales , Apoptosis/genética , Ciclo Celular , Cobre/efectos adversos , Larva , Retina/patología , Pez Cebra/genética , Estatmina/genética , Proteínas de Pez Cebra/genéticaRESUMEN
Epigenetic regulators play key roles in cancer and are increasingly being targeted for treatment. However, for many, little is known about mechanisms of resistance to the inhibition of these regulators. We have generated a model of resistance to inhibitors of protein arginine methyltransferase 5 (PRMT5). This study was conducted in KrasG12D;Tp53-null lung adenocarcinoma (LUAD) cell lines. Resistance to PRMT5 inhibitors (PRMT5i) arose rapidly, and barcoding experiments showed that this resulted from a drug-induced transcriptional state switch, not selection of a preexisting population. This resistant state is both stable and conserved across variants arising from distinct LUAD lines. Moreover, it brought with it vulnerabilities to other chemotherapeutics, especially the taxane paclitaxel. This paclitaxel sensitivity depended on the presence of stathmin 2 (STMN2), a microtubule regulator that is specifically expressed in the resistant state. Remarkably, STMN2 was also essential for resistance to PRMT5 inhibition. Thus, a single gene is required for both acquisition of resistance to PRMT5i and collateral sensitivity to paclitaxel in our LUAD cells. Accordingly, the combination of PRMT5i and paclitaxel yielded potent and synergistic killing of the murine LUAD cells. Importantly, the synergy between PRMT5i and paclitaxel also extended to human cancer cell lines. Finally, analysis of The Cancer Genome Atlas patient data showed that high STMN2 levels correlate with complete regression of tumors in response to taxane treatment. Collectively, this study reveals a recurring mechanism of PRMT5i resistance in LUAD and identifies collateral sensitivities that have potential clinical relevance.
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Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Paclitaxel/farmacología , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular , Sinergismo Farmacológico , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Ratones , Mutación , Estatmina/genética , Estatmina/metabolismoRESUMEN
BACKGROUNDS: Nasopharyngeal carcinoma is a common malignancy in the head and neck. Baicalein has been reported to exert the anticancer effects on various cancers. In this study, our aim was to explore the function of baicalein in the development of nasopharyngeal carcinoma and further investigate the potential underlying mechanisms. METHODS: Cell Counting Kit (CCK)-8 assay, EdU assay, sphere formation assay, flow cytometry, and transwell invasion assay were conducted to determine cell proliferation, stemness, apoptosis, and invasion, respectively. Western blot was performed to examine the protein levels of PCNA, MMP9, STMN1, ß-catenin, and Wnt3A. The mRNA level of STMN1 was assessed using real-time quantitative polymerase chain reaction (RT-qPCR). Xenograft tumor model was carried out to evaluate the effects of baicalein on tumor growth in vivo. Immunohistochemistry (IHC) assay was used to detect the levels of PCNA, MMP9, and STMN1 in tumor tissues from mice. RESULTS: Baicalein significantly induced cell apoptosis and impeded cell proliferation, invasion, and stemness of nasopharyngeal carcinoma cells. STMN1 was highly expressed in nasopharyngeal carcinoma, and baicalein could directly downregulate STMN1 expression. STMN1 knockdown hampered the progression of nasopharyngeal carcinoma cells. Moreover, the effects of baicalein on cell proliferation, stemness, invasion, and apoptosis in nasopharyngeal carcinoma cells were harbored by STMN1 overexpression. Baicalein regulated STMN1 to inhibit the activation of the Wnt/ß-catenin pathway. SKL2001, an agonist of the Wnt/ß-catenin pathway, could reverse the effects of STMN1 knockdown on the progression of nasopharyngeal carcinoma. In addition, baicalein markedly impeded tumor growth in vivo. CONCLUSION: Baicalein regulated the STMN1/Wnt/ß-catenin pathway to restrain the development of nasopharyngeal carcinoma.
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Flavanonas , Metaloproteinasa 9 de la Matriz , Neoplasias Nasofaríngeas , Animales , Humanos , Ratones , Apoptosis/genética , beta Catenina/genética , beta Catenina/metabolismo , Movimiento Celular/genética , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Metaloproteinasa 9 de la Matriz/metabolismo , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , Estatmina/genética , Estatmina/metabolismo , Estatmina/farmacologíaRESUMEN
Microtubule dynamics is modulated by many cellular factors including stathmin family proteins. Vertebrate stathmins sequester two αß-tubulin heterodimers into a tight complex that cannot be incorporated in microtubules. Stathmins are regulated at the expression level during development and among tissues; they are also regulated by phosphorylation. Here, we study the dissociation kinetics of tubulin:stathmin assemblies in presence of different tubulin-binding proteins and identify a critical role of the C-terminus of the stathmin partner. Destabilizing this C-terminal region may represent an additional regulatory mechanism of the interaction with tubulin of stathmin proteins.
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Estatmina , Tubulina (Proteína) , Proteínas de Microtúbulos/análisis , Proteínas de Microtúbulos/metabolismo , Microtúbulos/metabolismo , Fosfoproteínas/metabolismo , Unión Proteica , Estatmina/metabolismo , Tubulina (Proteína)/metabolismoRESUMEN
Synapses exhibit an astonishing degree of adaptive plasticity in healthy and disease states. We have investigated whether synapses also adjust to life stages imposed by novel developmental programs for which they were never molded by evolution. Under conditions in which Drosophila larvae are terminally arrested, we have characterized synaptic growth, structure and function at the neuromuscular junction (NMJ). Although wild-type larvae transition to pupae after 5â days, arrested third instar (ATI) larvae persist for 35â days, during which time NMJs exhibit extensive overgrowth in muscle size, presynaptic release sites and postsynaptic glutamate receptors. Remarkably, despite this exuberant growth, stable neurotransmission is maintained throughout the ATI lifespan through a potent homeostatic reduction in presynaptic neurotransmitter release. Arrest of the larval stage in stathmin mutants also reveals a degree of progressive instability and neurodegeneration that was not apparent during the typical larval period. Hence, an adaptive form of presynaptic depression stabilizes neurotransmission during an extended developmental period of unconstrained synaptic growth. More generally, the ATI manipulation provides a powerful system for studying neurodegeneration and plasticity across prolonged developmental timescales.
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Drosophila/crecimiento & desarrollo , Drosophila/genética , Larva/crecimiento & desarrollo , Larva/genética , Depresión Sináptica a Largo Plazo/genética , Degeneración Nerviosa/genética , Unión Neuromuscular/crecimiento & desarrollo , Animales , Axones/patología , Proteínas de Drosophila/genética , Femenino , Homeostasis/genética , Masculino , Mutación , Unión Neuromuscular/metabolismo , Interferencia de ARN , Proteínas Smad Reguladas por Receptores/genética , Estatmina/genética , Sinapsis/metabolismo , Transmisión Sináptica/genéticaRESUMEN
ABSTRACT: Studies on the relationship between stathmin 1 (STMN1) and cutaneous squamous cell carcinoma (cSCC) are limited. We aimed to evaluate the relationship between clinicopathological factors and STMN1 and p53 expressions in cSCC and compare them with those in the precursor lesions of cSCC and normal tissue. A total of 195 patients, followed between January 2014 and December 2021, with diagnoses of primary cSCC (n = 129), in situ cSCC (n = 20), or actinic keratosis (n = 46), as well as 29 histopathologically normal tissue samples, were included in the study. Immunohistochemical staining for STMN1 and p53 was performed. In the cSCC group, STMN1 scores were higher in poorly differentiated ( P = 0.001) and ulcerated ( P < 0.001) tumors. A linear relationship between STMN1 score and tumor area, tumor thickness, and mitosis was found ( P = 0.001, P = 0.003, and P < 0.001, respectively). There was no statistically significant correlation between STMN1 and p53 scores. Our results support the previous view that STMN1 may be associated with some adverse clinicopathological and high-risk features of cSCC. To the best of our knowledge, this is the first and largest study to investigate STMN1 expression in cSCC, precancerous lesions of cSCC, and normal tissues.
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Carcinoma de Células Escamosas , Neoplasias Cutáneas , Humanos , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/patología , Neoplasias Cutáneas/patología , Estatmina/metabolismo , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
A precise sequence of axon guidance events is required for the development of the ocular motor system. Three cranial nerves grow toward, and connect with, six extraocular muscles in a stereotyped pattern, to control eye movements. The signaling protein alpha2-chimaerin (α2-CHN) plays a pivotal role in the formation of the ocular motor system; mutations in CHN1, encoding α2-CHN, cause the human eye movement disorder Duane Retraction Syndrome (DRS). Our research has demonstrated that the manipulation of α2-chn signaling in the zebrafish embryo leads to ocular motor axon wiring defects, although the signaling cascades regulated by α2-chn remain poorly understood. Here, we demonstrate that several cytoskeletal regulatory proteins-collapsin response mediator protein 2 (CRMP2; encoded by the gene dpysl2), stathmin1, and stathmin 2-bind to α2-CHN. dpysl2, stathmin1, and especially stathmin2 are expressed by ocular motor neurons. We find that the manipulation of dpysl2 and of stathmins in zebrafish larvae leads to defects in both the axon wiring of the ocular motor system and the optokinetic reflex, impairing horizontal eye movements. Knockdowns of these molecules in zebrafish larvae of either sex caused axon guidance phenotypes that included defasciculation and ectopic branching; in some cases, these phenotypes were reminiscent of DRS. chn1 knock-down phenotypes were rescued by the overexpression of CRMP2 and STMN1, suggesting that these proteins act in the same signaling pathway. These findings suggest that CRMP2 and stathmins signal downstream of α2-CHN to orchestrate ocular motor axon guidance and to control eye movements.SIGNIFICANCE STATEMENT The precise control of eye movements is crucial for the life of vertebrate animals, including humans. In humans, this control depends on the arrangement of nerve wiring of the ocular motor system, composed of three nerves and six muscles, a system that is conserved across vertebrate phyla. Mutations in the protein alpha2-chimaerin have previously been shown to cause eye movement disorders (squint) and axon wiring defects in humans. Our recent work has unraveled how alpha2-chimaerin coordinates axon guidance of the ocular motor system in animal models. In this article, we demonstrate key roles for the proteins CRMP2 and stathmin 1/2 in the signaling pathway orchestrated by alpha2-chimaerin, potentially giving insight into the etiology of eye movement disorders in humans.
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Orientación del Axón/fisiología , Quimerina 1/metabolismo , Neuronas Motoras/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Músculos Oculomotores/inervación , Estatmina/metabolismo , Proteínas de Pez Cebra/metabolismo , Animales , Quimerina 1/genética , Síndrome de Retracción de Duane/genética , Movimientos Oculares , Transducción de Señal/fisiología , Pez CebraRESUMEN
Exposure of mucosal epithelial cells to the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 is known to disrupt epithelial cell junctions by impairing stathmin-mediated microtubule depolymerization. However, the pathological significance of this process and its underlying molecular mechanism remain unclear. Here we show that treatment of epithelial cells with pseudotyped HIV-1 viral particles or recombinant gp120 protein results in the activation of protein kinase G 1 (PKG1). Examination of epithelial cells by immunofluorescence microscopy reveals that PKG1 activation mediates the epithelial barrier damage upon HIV-1 exposure. Immunoprecipitation experiments show that PKG1 interacts with stathmin and phosphorylates stathmin at serine 63 in the presence of gp120. Immunoprecipitation and immunofluorescence microscopy further demonstrate that PKG1-mediated phosphorylation of stathmin promotes its autophagic degradation by enhancing the interaction between stathmin and the autophagy adaptor protein p62. Collectively, these results suggest that HIV-1 exposure exploits the PKG1/stathmin axis to affect the microtubule cytoskeleton and thereby perturbs epithelial cell junctions. Our findings reveal a novel molecular mechanism by which exposure to HIV-1 increases epithelial permeability, which has implications for the development of effective strategies to prevent mucosal HIV-1 transmission.
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Permeabilidad de la Membrana Celular , Proteínas Quinasas Dependientes de GMP Cíclico/metabolismo , Células Epiteliales/patología , VIH-1/fisiología , Microtúbulos/metabolismo , Estatmina/metabolismo , Movimiento Celular , Proteínas Quinasas Dependientes de GMP Cíclico/genética , Células Epiteliales/metabolismo , Células Epiteliales/virología , Infecciones por VIH/virología , Humanos , Microtúbulos/virología , Fosforilación , Estatmina/genéticaRESUMEN
Cell division ends when two daughter cells physically separate via abscission, the cleavage of the intercellular bridge. It is not clear how the anti-parallel microtubule bundles bridging daughter cells are severed. Here, we present a novel abscission mechanism. We identified chromokinesin KIF4A, which is adjacent to the midbody during cytokinesis, as being required for efficient abscission. KIF4A is regulated by post-translational modifications. We evaluated modification of KIF4A by the ubiquitin-like protein SUMO. We mapped lysine 460 in KIF4A as the SUMO acceptor site and employed CRISPR-Cas9-mediated genome editing to block SUMO conjugation of endogenous KIF4A. Failure to SUMOylate this site in KIF4A delayed cytokinesis. SUMOylation of KIF4A enhanced the affinity for the microtubule destabilizer stathmin 1 (STMN1). We here present a new level of abscission regulation through the dynamic interactions between KIF4A and STMN1 as controlled by SUMO modification of KIF4A.
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Mitosis , Estatmina , Citocinesis/genética , Proteínas de Unión al ADN , Células HeLa , Humanos , Cinesinas/genética , Proteínas Nucleares , Estatmina/genéticaRESUMEN
Stathmin 1 (STMN1) is a microtubule-destabilizing protein highly expressed in hematological malignancies and involved in proliferation and differentiation. Although a previous study found that the PML-RARα fusion protein, which contributes to the pathophysiology of acute promyelocytic leukemia (APL), positively regulates STMN1 at the transcription and protein activity levels, little is known about the role of STMN1 in APL. In this study, we aimed to investigate the STMN1 expression levels and their associations with laboratory, clinical, and genomic data in APL patients. We also assessed the dynamics of STMN1 expression during myeloid cell differentiation and cell cycle progression, and the cellular effects of STMN1 silencing and pharmacological effects of microtubule-stabilizing drugs on APL cells. We found that STMN1 transcripts were significantly increased in samples from APL patients compared with those of healthy donors (all p < 0.05). However, this had no effect on clinical outcomes. STMN1 expression was associated with proliferation- and metabolism-related gene signatures in APL. Our data confirmed that STMN1 was highly expressed in early hematopoietic progenitors and reduced during cell differentiation, including the ATRA-induced granulocytic differentiation model. STMN1 phosphorylation was predominant in a pool of mitosis-enriched APL cells. In NB4 and NB4-R2 cells, STMN1 knockdown decreased autonomous cell growth (all p < 0.05) but did not impact ATRA-induced apoptosis and differentiation. Finally, treatment with paclitaxel (as a single agent or combined with ATRA) induced microtubule stabilization, resulting in mitotic catastrophe with repercussions for cell viability, even in ATRA-resistant APL cells. This study provides new insights into the STMN1 functions and microtubule dynamics in APL.
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Leucemia Promielocítica Aguda , Diferenciación Celular , Proliferación Celular , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patología , Mitosis , Proteínas de Fusión Oncogénica/genética , Paclitaxel , Estatmina/genéticaRESUMEN
Uterine leiomyosarcoma is an aggressive soft tissue tumor. Stathmin, a phosphoprotein that modulates microtubule dynamics, is highly expressed in many malignancies including leiomyosarcoma. The microtubule-depolymerizing agent eribulin has been recently approved for treating malignant soft tissue tumors. Although eribulin inhibits microtubule polymerization, little is known about the relationship between eribulin treatment and stathmin dynamics. In this study, we explored the role of stathmin expression in the action of eribulin in leiomyosarcoma cells. Eribulin induced phosphorylation of stathmin and reduced expression of subunits A and C of protein phosphatase 2A (PP2A) in a leiomyosarcoma cell line. The PP2A activator FTY720 reduced levels of phosphorylated stathmin. Eribulin decreased stathmin protein levels without affecting stathmin mRNA expression. Furthermore, stathmin knockdown attenuated the inhibitory effects of eribulin on cell viability, whereas stathmin overexpression enhanced the anti-proliferative effect of eribulin. Eribulin-resistant leiomyosarcoma cell lines had enhanced expression of the class â ß-tubulin TUBB1, multi-drug resistance 1 protein MDR1 and breast cancer-resistance protein BCRP, and decreased expression of stathmin. Taken together, these results suggest that stathmin expression modulates the pharmacological efficacy of eribulin in uterine leiomyosarcoma cells.
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Leiomiosarcoma , Estatmina , Humanos , Estatmina/genética , Estatmina/metabolismo , Estatmina/farmacología , Leiomiosarcoma/tratamiento farmacológico , Leiomiosarcoma/genética , Leiomiosarcoma/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Proteínas de Neoplasias/metabolismo , Microtúbulos/metabolismo , Microtúbulos/patologíaRESUMEN
PURPOSE: Femoral head necrosis (FHN) is a common disease of hip. However, the pathogenesis of FHN is not well understood. This study attempted to explore the potentially important genes and proteins involved in FHN. METHODS: We integrated the transcriptomic and proteomic methods to quantitatively screen the differentially expressed genes (DEGs) and proteins (DEPs) between Control and FHN groups. Gene ontology (GO) terms and KEGG pathway enrichment analysis were used to assess the roles of DEGs and DEPs. qRT-PCR and western blot were performed to verify the key genes/proteins in FHN. CCK-8 assay was performed to measure cell viability. The protein expression of Bax and Bcl-2 were used to evaluate cell apoptosis. RESULTS: Transcriptome and proteome studies indicated 758 DEGs and 1097 DEPs between Control and FHN groups, respectively. Cell division, extracellular exosome, and serine-type endopeptidase activity were the most common terms in biological process (BP), cellular component (CC), and molecular function (MF) enrichment, respectively. DEPs were mainly enriched in cellular process, cell, and binding for BP, CC, and MF categories, respectively. DEGs were mainly involved in PI3K-Akt pathway and DEPs were mainly focused in glycolysis/gluconeogenesis pathway. Notably, 14 down-regulated and 22 up-regulated genes/proteins were detected at both the transcript and protein level. LRG1, SERPINE2, STMN1, COL14A1, SLC37A2, and MMP2 were determined as the key genes/proteins in FHN. SERPINE2/STMN1 overexpression increased viability and decreased apoptosis of dexamethasone-treated MC3T3-E1 cells. CONCLUSIONS: Our study investigated some pivotal regulatory genes/proteins in the pathogenesis of FHN, providing novel insight into the genes/proteins involved in FHN.
Asunto(s)
Necrosis de la Cabeza Femoral/genética , Proteoma/genética , Proteómica , Transcriptoma/genética , Células 3T3 , Animales , Supervivencia Celular/genética , Dexametasona/farmacología , Necrosis de la Cabeza Femoral/inducido químicamente , Necrosis de la Cabeza Femoral/patología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/genética , Ontología de Genes , Humanos , Ratones , Fosfatidilinositol 3-Quinasas/genética , Proteoma/clasificación , Proteínas Proto-Oncogénicas c-bcl-2/genética , Serpina E2/genética , Estatmina/genética , Esteroides/toxicidad , Proteína X Asociada a bcl-2/genéticaRESUMEN
Eribulin, an inhibitor of microtubule dynamics, is used for treating breast cancers and sarcomas. The microtubule-destabilizing protein stathmin may modulate the antiproliferative activity of eribulin on breast cancer cells and leiomyosarcoma cells. The antitumor activity of eribulin in ovarian cancers has not been fully explored, so the present study aimed to determine the antitumor efficacy of eribulin and the involvement of stathmin in ovarian cancers. In a xenograft model of ovarian cancer, eribulin treatment reduced the tumor weight, which was accompanied by an increased level of phosphorylated stathmin. Eribulin stimulated the phosphorylation of stathmin in cultured cancer cell lines. The eribulin-induced phosphorylation of stathmin was inhibited by treatment with FTY720, an activator of protein phosphatase 2A (PP2A), and eribulin downregulated the expression of PP2A subunits. Furthermore, stathmin knockdown abrogated the inhibitory effects of eribulin on cell viability. Eribulin enhanced the antiproliferative effects of paclitaxel and concomitantly decreased stathmin expression. These results suggest that eribulin-induced phosphorylation of stathmin, mediated in part by PP2A downregulation, reduces stathmin activity and enhances the antiproliferative effects of paclitaxel in ovarian cancer. Collectively, the results of this study indicate that eribulin may suppress the proliferation of ovarian cancer cells partly by regulating the activity of stathmin.
Asunto(s)
Neoplasias Ováricas , Paclitaxel , Humanos , Femenino , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Estatmina/metabolismo , Estatmina/farmacología , Línea Celular Tumoral , Neoplasias Ováricas/metabolismo , MicrotúbulosRESUMEN
Breast cancer is the most common malignant neoplasm among women, responsible for 30% of all malignant tumours, and the second most significant reason of cancer fatality in women. Treatment failure and tumour recurrence are common outcomes of chemotherapy when patients develop multidrug resistance (MDR). New therapeutic methods like molecularly targeted therapeutic interventions need a thorough understanding of malignant tumour's molecular processes. Numerous studies published in the last few years indicate that stathmin and tubulin-associated units (tau) are upregulated in a range of human malignant tumours, suggesting that they may enhance the incidence and progression of malignancies. By promoting cancer cell reproduction, infiltration and generating drug resistance, these proteins aid in the disease's development. Existing information on the expression of tau protein and stathmin in breast cancer, as well as their involvement in treatment methods, is summarized in this literature review.
Asunto(s)
Neoplasias de la Mama , Estatmina , Neoplasias de la Mama/patología , Femenino , Humanos , Masculino , Microtúbulos/metabolismo , Microtúbulos/patología , Recurrencia Local de Neoplasia/metabolismo , Estatmina/metabolismoRESUMEN
BACKGROUND: Upregulation of Stathmin 1 (STMN1), a cytoplasmic phosphoprotein that controls the dynamics of cellular microtubules, is linked to malignant behavior and poor prognosis in a range of malignancies. However, little research has been done on STMN1's potential role in HCC as a single factor in DNA methylation, m6A, or immunological modulation. RESULTS: STMN1 is overexpressed in hepatocellular carcinoma, where it is related to clinicopathological parameters and affects the prognosis of HCC patients. STMN1 overexpression plays an important role in the diagnosis and prognosis of hepatocellular carcinoma. Meanwhile, methylation of 7 CpG sites of STMN1 in HCC was correlated with prognosis, and STMN1 expression was closely related to m6A modification. In addition, STMN1 expression is associated with immune cell infiltration, immune molecules, and immune checkpoints in HCC. CONCLUSION: STMN1 has a significant role in hepatocellular carcinoma diagnosis and prediction. STMN1 is implicated not just in the onset and course but also in the immunological modulation of the disease. DNA methylation and m6A are both linked to STMN1. Therefore, STMN1 could be used as a diagnostic and prognostic biomarker for HCC, as well as a target for immunotherapy.