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1.
J Biochem Mol Toxicol ; 38(2): e23647, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348718

RESUMO

Hepatocellular carcinoma (HCC) is among the world's worst malignancies. Nuclear division cycle 1 (NDC1) is an essential membrane-integral nucleoporin, found in this study to be significantly increased in primary HCC. A multivariate analysis revealed that higher NDC1 expression was linked to worse outcome in HCC patients. Mouse xenograft tumors overexpressing NDC1 grew rapidly, and HCC cells overexpressing NDC1 showed enhanced proliferation, invasion, and migration in vitro. In contrast, knocking down NDC1 had the opposite effects in vitro. Furthermore, co-immunoprecipitation and liquid chromatograph mass spectrometer analyses revealed that NDC1 activated PI3K/AKT signaling by interacting with BCAP31. In summary, NDC1 and BCAP31 cooperate to promote the PI3K/AKT pathway, which is essential for HCC carcinogenesis. This suggests that NDC1 is predictive of prognosis in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinogênese , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Divisão do Núcleo Celular , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
2.
J Cell Sci ; 137(1)2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38224461

RESUMO

Chromosomal instability (CIN), an increased rate of chromosome segregation errors during mitosis, is a hallmark of cancer cells. CIN leads to karyotype differences between cells and thus large-scale heterogeneity among individual cancer cells; therefore, it plays an important role in cancer evolution. Studying CIN and its consequences is technically challenging, but various technologies have been developed to track karyotype dynamics during tumorigenesis, trace clonal lineages and link genomic changes to cancer phenotypes at single-cell resolution. These methods provide valuable insight not only into the role of CIN in cancer progression, but also into cancer cell fitness. In this Cell Science at a Glance article and the accompanying poster, we discuss the relationship between CIN, cancer cell fitness and evolution, and highlight techniques that can be used to study the relationship between these factors. To that end, we explore methods of assessing cancer cell fitness, particularly for chromosomally unstable cancer.


Assuntos
Neoplasias , Humanos , Neoplasias/genética , Carcinogênese , Instabilidade Cromossômica/genética , Transformação Celular Neoplásica , Divisão do Núcleo Celular
3.
J Cell Sci ; 136(21)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815466

RESUMO

Connections between the nucleus and the cytoskeleton are important for positioning and division of the nucleus. In most eukaryotes, the linker of nucleoskeleton and cytoskeleton (LINC) complex spans the outer and inner nuclear membranes and connects the nucleus to the cytoskeleton. In opisthokonts, it is composed of Klarsicht, ANC-1 and Syne homology (KASH) domain proteins and Sad1 and UNC-84 (SUN) domain proteins. Given that the nucleus is positioned at the posterior pole of Toxoplasma gondii, we speculated that apicomplexan parasites must have a similar mechanism that integrates the nucleus and the cytoskeleton. Here, we identified three UNC family proteins in the genome of the apicomplexan parasite T. gondii. Whereas the UNC-50 protein TgUNC1 localised to the Golgi and appeared to be not essential for the parasite, the SUN domain protein TgSLP2 showed a diffuse pattern throughout the parasite. The second SUN domain protein, TgSLP1, was expressed in a cell cycle-dependent manner and was localised close to the mitotic spindle and, more detailed, at the kinetochore. We demonstrate that conditional knockout of TgSLP1 leads to failure of nuclear division and loss of centrocone integrity.


Assuntos
Parasitos , Toxoplasma , Animais , Toxoplasma/genética , Membrana Nuclear/metabolismo , Fuso Acromático , Divisão do Núcleo Celular
4.
Medicine (Baltimore) ; 102(35): e34717, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37657045

RESUMO

NUMB has been initially identified as a critical cell fate determinant that modulates cell differentiation via asymmetrical partitioning during mitosis, including tumor cells. However, it remains absent that a systematic assessment of the mechanisms underlying NUMB and its homologous protein NUMBLIKE (NUMBL) involvement in cancer. This study aimed to investigate the prognostic significance for NUMB and NUMBL in pan-cancer. In this study, using the online databases TIMER2.0, gene expression profiling interactive analysis, cBioPortal, the University of ALabama at Birmingham CANcer data analysis Portal, SearchTool for the Retrieval of Interacting Genes/Proteins, and R software, we focused on the relevance between NUMB/NUMBL and oncogenesis, progression, mutation, phosphorylation, function and prognosis. This study demonstrated that abnormal expression of NUMB and NUMBL were found to be significantly associated with clinicopathologic stages and the prognosis of survival. Besides, genetic alternations of NUMB and NUMBL focused on uterine corpus endometrial carcinoma, and higher genetic mutations of NUMBL were correlated with more prolonged overall survival and disease-free survival in different cancers. Moreover, S438 locus of NUMB peptide fragment was frequently phosphorylated in 4 cancer types and relevant to its phosphorylation sites. Furthermore, endocytosis processing and neurogenesis regulation were involved in the functional mechanisms of NUMB and NUMBL separately. Additionally, the pathway enrichment suggested that NUMB was implicated in Hippo, Neurotrophin, Thyroid hormone, and FoxO pathways, while MAPK, Hippo, Rap1, mTOR, and Notch pathways were related to the functions of NUMBL. This study highlights the predictive roles of NUMB and NUMBL in pan-cancer, suggesting NUMB and NUMBL might be served as potential biomarkers for diagnosis and prognosis in various malignant tumors.


Assuntos
Carcinogênese , Carcinoma Endometrioide , Humanos , Feminino , Prognóstico , Diferenciação Celular , Divisão do Núcleo Celular , Peptídeos e Proteínas de Sinalização Intracelular
5.
Nat Commun ; 14(1): 5652, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37704606

RESUMO

The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities by distinct protein scaffolds. Plasmodium spp., the causative agents of malaria, are unicellular eukaryotes with three unique and highly divergent aurora-related kinases (ARK1-3) that are essential for asexual cellular proliferation but lack most canonical scaffolds/activators. Here we investigate the role of ARK2 during sexual proliferation of the rodent malaria Plasmodium berghei, using a combination of super-resolution microscopy, mass spectrometry, and live-cell fluorescence imaging. We find that ARK2 is primarily located at spindle microtubules in the vicinity of kinetochores during both mitosis and meiosis. Interactomic and co-localisation studies reveal several putative ARK2-associated interactors including the microtubule-interacting protein EB1, together with MISFIT and Myosin-K, but no conserved eukaryotic scaffold proteins. Gene function studies indicate that ARK2 and EB1 are complementary in driving endomitotic division and thereby parasite transmission through the mosquito. This discovery underlines the flexibility of molecular networks to rewire and drive unconventional mechanisms of chromosome segregation in the malaria parasite.


Assuntos
Divisão do Núcleo Celular , Segregação de Cromossomos , Animais , Plasmodium berghei/genética , Proliferação de Células , Meiose , Aurora Quinases , Eucariotos
6.
Nat Commun ; 14(1): 5317, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658044

RESUMO

Accurate chromosome segregation in mitosis depends on multiprotein structures called kinetochores that are built on the centromeric region of sister chromatids and serve to capture mitotic spindle microtubules. In early mitosis, unattached kinetochores expand a crescent-shaped structure called fibrous corona whose function is to facilitate initial kinetochore-microtubule attachments and chromosome transport by microtubules. Subsequently, the fibrous corona must be timely disassembled to prevent segregation errors. Although recent studies provided new insights on the molecular content and mechanism of fibrous corona assembly, it remains unknown what triggers the disassembly of the outermost and dynamic layer of the kinetochore. Here, we show that Aurora A and B kinases phosphorylate CENP-E to release it from an autoinhibited state. At kinetochores, Aurora B phosphorylates CENP-E to prevent its premature removal together with other corona proteins by dynein. At the spindle poles, Aurora A phosphorylates CENP-E to promote chromosome congression and prevent accumulation of corona proteins at the centrosomes, allowing for their intracellular redistribution. Thus, we propose the Aurora A/B-CENP-E axis as a critical element of the long-sought-for mechanism of fibrous corona disassembly that is essential for accurate chromosome segregation.


Assuntos
Centrômero , Cinetocoros , Divisão do Núcleo Celular , Centrossomo , Fuso Acromático , Humanos
7.
PLoS Genet ; 19(8): e1010854, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37639467

RESUMO

Transcription of ribosomal RNA (rRNA) by RNA Polymerase (Pol) I in the nucleolus is necessary for ribosome biogenesis, which is intimately tied to cell growth and proliferation. Perturbation of ribosome biogenesis results in tissue specific disorders termed ribosomopathies in association with alterations in nucleolar structure. However, how rRNA transcription and ribosome biogenesis regulate nucleolar structure during normal development and in the pathogenesis of disease remains poorly understood. Here we show that homozygous null mutations in Pol I subunits required for rRNA transcription and ribosome biogenesis lead to preimplantation lethality. Moreover, we discovered that Polr1a-/-, Polr1b-/-, Polr1c-/- and Polr1d-/- mutants exhibit defects in the structure of their nucleoli, as evidenced by a decrease in number of nucleolar precursor bodies and a concomitant increase in nucleolar volume, which results in a single condensed nucleolus. Pharmacological inhibition of Pol I in preimplantation and midgestation embryos, as well as in hiPSCs, similarly results in a single condensed nucleolus or fragmented nucleoli. We find that when Pol I function and rRNA transcription is inhibited, the viscosity of the granular compartment of the nucleolus increases, which disrupts its phase separation properties, leading to a single condensed nucleolus. However, if a cell progresses through mitosis, the absence of rRNA transcription prevents reassembly of the nucleolus and manifests as fragmented nucleoli. Taken together, our data suggests that Pol I function and rRNA transcription are required for maintaining nucleolar structure and integrity during development and in the pathogenesis of disease.


Assuntos
Nucléolo Celular , Divisão do Núcleo Celular , Nucléolo Celular/genética , Ciclo Celular , Proliferação de Células , RNA Polimerase I/genética , RNA Ribossômico/genética
8.
Nat Commun ; 14(1): 5246, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37640708

RESUMO

Molecular chaperone HSP70s are attractive targets for cancer therapy, but their substrate broadness and functional non-specificity have limited their role in therapeutical success. Functioning as HSP70's cochaperones, HSP40s determine the client specificity of HSP70s, and could be better targets for cancer therapy. Here we show that tumors defective in HSP40 member DNAJA2 are benefitted from immune-checkpoint blockade (ICB) therapy. Mechanistically, DNAJA2 maintains centrosome homeostasis by timely degrading key centriolar satellite proteins PCM1 and CEP290 via HSC70 chaperone-mediated autophagy (CMA). Tumor cells depleted of DNAJA2 or CMA factor LAMP2A exhibit elevated levels of centriolar satellite proteins, which causes aberrant mitosis characterized by abnormal spindles, chromosome missegregation and micronuclei formation. This activates the cGAS-STING pathway to enhance ICB therapy response in tumors derived from DNAJA2-deficient cells. Our study reveals a role for DNAJA2 to regulate mitotic division and chromosome stability and suggests DNAJA2 as a potential target to enhance cancer immunotherapy, thereby providing strategies to advance HSPs-based cancer therapy.


Assuntos
Divisão do Núcleo Celular , Mitose , Humanos , Cromogranina A , Nucleotidiltransferases/genética , Instabilidade Cromossômica , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico HSP40
9.
Phys Rev E ; 108(1-1): 014401, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37583222

RESUMO

Saccharomyces cerevisiae and Candida albicans, the two well-known human pathogens, can be found in all three morphologies, i.e., yeast, pseudohyphae, and true hyphae. The cylindrical daughter-bud (germ tube) grows very long for true hyphae, and the cell cycle is delayed compared to the other two morphologies. The place of the nuclear division is specific for true hyphae determined by the position of the septin ring. However, the septin ring can localize anywhere inside the germ tube, unlike the mother-bud junction in budding yeast. Since the nucleus often migrates a long path in the hyphae, the underlying mechanism must be robust for executing mitosis in a timely manner. We explore the mechanism of nuclear migration through hyphae in light of mechanical interactions between astral microtubules and the cell cortex. We report that proper migration through constricted hyphae requires a large dynein pull applied on the astral microtubules from the hyphal cortex. This is achieved when the microtubules frequently slide along the hyphal cortex so that a large population of dyneins actively participate, pulling on them. Simulation shows timely migration when the dyneins from the mother cortex do not participate in pulling on the microtubules. These findings are robust for long migration and positioning of the nucleus in the germ tube at the septin ring.


Assuntos
Dineínas , Proteínas Fúngicas , Humanos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Dineínas/metabolismo , Hifas/metabolismo , Septinas/metabolismo , Mitose , Saccharomyces cerevisiae/metabolismo , Divisão do Núcleo Celular , Microtúbulos/metabolismo
10.
Proc Natl Acad Sci U S A ; 120(35): e2305037120, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37603740

RESUMO

Polo-like kinase 1 (Plk1) is considered an attractive target for anticancer therapy. Over the years, studies on the noncatalytic polo-box domain (PBD) of Plk1 have raised the expectation of generating highly specific protein-protein interaction inhibitors. However, the molecular nature of the canonical PBD-dependent interaction, which requires extensive water network-mediated interactions with its phospholigands, has hampered efforts to identify small molecules suitable for Plk1 PBD drug discovery. Here, we report the identification of the first allosteric inhibitor of Plk1 PBD, called Allopole, a prodrug that can disrupt intracellular interactions between PBD and its cognate phospholigands, delocalize Plk1 from centrosomes and kinetochores, and induce mitotic block and cancer cell killing. At the structural level, its unmasked active form, Allopole-A, bound to a deep Trp-Phe-lined pocket occluded by a latch-like loop, whose adjoining region was required for securely retaining a ligand anchored to the phospho-binding cleft. Allopole-A binding completely dislodged the L2 loop, an event that appeared sufficient to trigger the dissociation of a phospholigand and inhibit PBD-dependent Plk1 function during mitosis. Given Allopole's high specificity and antiproliferative potency, this study is expected to open an unexplored avenue for developing Plk1 PBD-specific anticancer therapeutic agents.


Assuntos
Proteínas de Ciclo Celular , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Divisão do Núcleo Celular
11.
Sci Rep ; 13(1): 14306, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653108

RESUMO

Automatic mitosis detection from video is an essential step in analyzing proliferative behaviour of cells. In existing studies, a conventional object detector such as Unet is combined with a link prediction algorithm to find correspondences between parent and daughter cells. However, they do not take into account the biological constraint that a cell in a frame can correspond to up to two cells in the next frame. Our model called GNN-DOL enables mitosis detection by complementing a graph neural network (GNN) with a differentiable optimization layer (DOL) that implements the constraint. In time-lapse microscopy sequences cultured under four different conditions, we observed that the layer substantially improved detection performance in comparison with GNN-based link prediction. Our results illustrate the importance of incorporating biological knowledge explicitly into deep learning models.


Assuntos
Divisão do Núcleo Celular , Mitose , Redes Neurais de Computação , Algoritmos , Conhecimento
12.
Nat Commun ; 14(1): 2402, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160908

RESUMO

A fundamental goal in the organogenesis field is to understand how cells organize into tubular shapes. Toward this aim, we have established the hydro-vascular organ in the sea star Patiria miniata as a model for tubulogenesis. In this animal, bilateral tubes grow out from the tip of the developing gut, and precisely extend to specific sites in the larva. This growth involves cell migration coupled with mitosis in distinct zones. Cell proliferation requires FGF signaling, whereas the three-dimensional orientation of the organ depends on Wnt signaling. Specification and maintenance of tube cell fate requires Delta/Notch signaling. Moreover, we identify target genes of the FGF pathway that contribute to tube morphology, revealing molecular mechanisms for tube outgrowth. Finally, we report that FGF activates the Six1/2 transcription factor, which serves as an evolutionarily ancient regulator of branching morphogenesis. This study uncovers distinct mechanisms of tubulogenesis in vivo and we propose that cellular dynamics in the sea star hydro-vascular organ represents a key comparison for understanding the evolution of vertebrate organs.


Assuntos
Divisão do Núcleo Celular , Estrelas-do-Mar , Animais , Diferenciação Celular , Movimento Celular , Estrelas-do-Mar/genética , Via de Sinalização Wnt
13.
PLoS Pathog ; 19(3): e1011255, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36928713

RESUMO

The mitotic exit is a key step in cell cycle, but the mechanism of mitotic exit network in the wheat head blight fungus Fusarium graminearum remains unclear. F. graminearum infects wheat spikelets and colonizes the entire head by growing through the rachis node at the bottom of each spikelet. In this study, we found that a small GTPase FgTem1 plays an important role in F. graminearum pathogenicity and functions in regulating the formation of infection structures and invasive hyphal growth on wheat spikelets and wheat coleoptiles, but plays only little roles in vegetative growth and conidiation of the phytopathogen. FgTem1 localizes to both the inner nuclear periphery and the spindle pole bodies, and negatively regulates mitotic exit in F. graminearum. Furthermore, the regulatory mechanisms of FgTem1 have been further investigated by high-throughput co-immunoprecipitation and genetic strategies. The septins FgCdc10 and FgCdc11 were demonstrated to interact with the dominant negative form of FgTem1, and FgCdc11 was found to regulate the localization of FgTem1. The cell cycle arrest protein FgBub2-FgBfa1 complex was shown to act as the GTPase-activating protein (GAP) for FgTem1. We further demonstrated that a direct interaction exists between FgBub2 and FgBfa1 which crucially promotes conidiation, pathogenicity and DON production, and negatively regulates septum formation and nuclear division in F. graminearum. Deletion of FgBUB2 and FgBFA1 genes caused fewer perithecia and immature asci formations, and dramatically down-regulated trichothecene biosynthesis (TRI) gene expressions. Double deletion of FgBUB2/FgBFA1 genes showed that FgBUB2 and FgBFA1 have little functional redundancy in F. graminearum. In summary, we systemically demonstrated that FgTem1 and its GAP FgBub2-FgBfa1 complex are required for fungal development and pathogenicity in F. graminearum.


Assuntos
Fusarium , Proteínas Monoméricas de Ligação ao GTP , Virulência , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Divisão do Núcleo Celular , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Esporos Fúngicos
14.
Proc Natl Acad Sci U S A ; 120(10): e2120536120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848565

RESUMO

During mitosis, cells round up and utilize the interphase adhesion sites within the fibrous extracellular matrix (ECM) as guidance cues to orient the mitotic spindles. Here, using suspended ECM-mimicking nanofiber networks, we explore mitotic outcomes and error distribution for various interphase cell shapes. Elongated cells attached to single fibers through two focal adhesion clusters (FACs) at their extremities result in perfect spherical mitotic cell bodies that undergo significant 3-dimensional (3D) displacement while being held by retraction fibers (RFs). Increasing the number of parallel fibers increases FACs and retraction fiber-driven stability, leading to reduced 3D cell body movement, metaphase plate rotations, increased interkinetochore distances, and significantly faster division times. Interestingly, interphase kite shapes on a crosshatch pattern of four fibers undergo mitosis resembling single-fiber outcomes due to rounded bodies being primarily held in position by RFs from two perpendicular suspended fibers. We develop a cortex-astral microtubule analytical model to capture the retraction fiber dependence of the metaphase plate rotations. We observe that reduced orientational stability, on single fibers, results in increased monopolar mitotic defects, while multipolar defects become dominant as the number of adhered fibers increases. We use a stochastic Monte Carlo simulation of centrosome, chromosome, and membrane interactions to explain the relationship between the observed propensity of monopolar and multipolar defects and the geometry of RFs. Overall, we establish that while bipolar mitosis is robust in fibrous environments, the nature of division errors in fibrous microenvironments is governed by interphase cell shapes and adhesion geometries.


Assuntos
Divisão do Núcleo Celular , Mitose , Centrossomo , Aeronaves , Axônios
15.
J Cell Sci ; 136(3)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36695178

RESUMO

Nuclear envelope (NE) expansion must be controlled to maintain nuclear shape and function. The nuclear membrane expands massively during closed mitosis, enabling chromosome segregation within an intact NE. Phosphatidic acid (PA) and diacylglycerol (DG) can both serve as biosynthetic precursors for membrane lipid synthesis. How they are regulated in time and space and what the implications are of changes in their flux for mitotic fidelity are largely unknown. Using genetically encoded PA and DG probes, we show that DG is depleted from the inner nuclear membrane during mitosis in the fission yeast Schizosaccharomyces pombe, but PA does not accumulate, indicating that it is rerouted to membrane synthesis. We demonstrate that DG-to-PA conversion catalyzed by the diacylglycerol kinase Dgk1 (also known as Ptp4) and direct glycerophospholipid synthesis from DG by diacylglycerol cholinephosphotransferase/ethanolaminephosphotransferase Ept1 reinforce NE expansion. We conclude that DG consumption through both the de novo pathway and the Kennedy pathway fuels a spike in glycerophospholipid biosynthesis, controlling NE expansion and, ultimately, mitotic fidelity.


Assuntos
Membrana Nuclear , Schizosaccharomyces , Membrana Nuclear/metabolismo , Diglicerídeos/metabolismo , Mitose , Divisão do Núcleo Celular , Schizosaccharomyces/metabolismo , Glicerofosfolipídeos/metabolismo
16.
J Cell Sci ; 136(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36594556

RESUMO

Cancer cells have heterogeneous fitness, and this heterogeneity stems from genetic and epigenetic sources. Here, we sought to assess the contribution of asymmetric mitosis (AM) and time on the variability of fitness in sister cells. Around one quarter of sisters had differences in fitness, assessed as the intermitotic time (IMT), from 330 to 510 min. Phenotypes related to fitness, such as ERK activity (herein referring to ERK1 and ERK2, also known as MAPK3 and MAPK1, respectively), DNA damage and nuclear morphological phenotypes were also asymmetric at mitosis or turned asymmetric over the course of the cell cycle. The ERK activity of mother cell was found to influence the ERK activity and the IMT of the daughter cells, and cells with ERK asymmetry at mitosis produced more offspring with AMs, suggesting heritability of the AM phenotype for ERK activity. Our findings demonstrate how variabilities in sister cells can be generated, contributing to the phenotype heterogeneities in tumor cells.


Assuntos
Divisão do Núcleo Celular , Mitose , Mitose/genética , Ciclo Celular , Fosforilação , Células-Tronco
17.
Sci Rep ; 12(1): 20902, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463288

RESUMO

Breast cancer (BC) cell lines are useful experimental models to understand cancer biology. Yet, their relevance to modelling cancer remains unclear. To better understand the tumour-modelling efficacy of cell lines, we performed RNA-seq analyses on a combined dataset of 2D and 3D cultures of tumourigenic MCF7 and non-tumourigenic MCF10A. To our knowledge, this was the first RNA-seq dataset comprising of 2D and 3D cultures of MCF7 and MCF10A within the same experiment, which facilitates the elucidation of differences between MCF7 and MCF10A across culture types. We compared the genes and gene sets distinguishing MCF7 from MCF10A against separate RNA-seq analyses of clinical luminal A (LumA) and normal samples from the TCGA-BRCA dataset. Among the 1031 cancer-related genes distinguishing LumA from normal samples, only 5.1% and 15.7% of these genes also distinguished MCF7 from MCF10A in 2D and 3D cultures respectively, suggesting that different genes drive cancer-related differences in cell lines compared to clinical BC. Unlike LumA tumours which showed increased nuclear division-related gene expression compared to normal tissue, nuclear division-related gene expression in MCF7 was similar to MCF10A. Moreover, although LumA tumours had similar cell adhesion-related gene expression compared to normal tissues, MCF7 showed reduced cell adhesion-related gene expression compared to MCF10A. These findings suggest that MCF7 and MCF10A cell lines were limited in their ability to model cancer-related processes in clinical LumA tumours.


Assuntos
Divisão do Núcleo Celular , Transcriptoma , Humanos , Adesão Celular/genética , Células MCF-7 , RNA-Seq
18.
Med Oncol ; 40(1): 14, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352167

RESUMO

Hepatocellular carcinoma is the cancer with the highest incidence among liver cancers and how to treat this cancer effectively is still a difficult problem we must face. We selected meiotic nuclear divisions 1 (MND1) as the study object by combining data from The Cancer Genome Atlas (TCGA) database with prognostic survival analysis. We validated the value of MND1 in evaluating the prognosis of hepatocellular carcinoma through a diagnostic and prognostic model. At the same time, cellular experiments were used to demonstrate the effect of MND1 on hepatocellular carcinoma proliferation and migration. We used short hairpin RNA (shRNA) to knock down MND1 in Hun7 and HCCLM3 cell lines. Through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony formation assays, we found that knocking down MND1 reduced the proliferation of cells. Through wound healing and Transwell assays, we found that knocking down MND1 reduced cell migration and invasion. Moreover, we found that MND1 can promote the proliferation, migration, and invasion of Hep3B cells by overexpressing MND1. Therefore, in general, MND1 is expected to be a gene that can effectively diagnose and treat hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , RNA Interferente Pequeno , Divisão do Núcleo Celular , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Invasividade Neoplásica/genética
19.
Int J Mol Sci ; 23(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36232691

RESUMO

CENP-A is a histone variant found in high abundance at the centromere in humans. At the centromere, this histone variant replaces the histone H3 found throughout the bulk chromatin. Additionally, the centromere comprises tandem repeats of α-satellite DNA, which CENP-A nucleosomes assemble upon. However, the effect of the DNA sequence on the nucleosome assembly and centromere formation remains poorly understood. Here, we investigated the structure of nucleosomes assembled with the CENP-A variant using Atomic Force Microscopy. We assembled both CENP-A nucleosomes and H3 nucleosomes on a DNA substrate containing an α-satellite motif and characterized their positioning and wrapping efficiency. We also studied CENP-A nucleosomes on the 601-positioning motif and non-specific DNA to compare their relative positioning and stability. CENP-A nucleosomes assembled on α-satellite DNA did not show any positional preference along the substrate, which is similar to both H3 nucleosomes and CENP-A nucleosomes on non-specific DNA. The range of nucleosome wrapping efficiency was narrower on α-satellite DNA compared with non-specific DNA, suggesting a more stable complex. These findings indicate that DNA sequence and histone composition may be two of many factors required for accurate centromere assembly.


Assuntos
Divisão do Núcleo Celular , Proteína Centromérica A , Centrômero , DNA , Histonas , Nucleossomos , Autoantígenos/química , Autoantígenos/genética , Divisão do Núcleo Celular/genética , Divisão do Núcleo Celular/fisiologia , Centrômero/genética , Centrômero/metabolismo , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Cromatina/genética , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , DNA/química , DNA/genética , DNA/metabolismo , DNA Satélite , Histonas/genética , Histonas/metabolismo , Humanos , Microscopia de Força Atômica , Nucleossomos/genética , Nucleossomos/metabolismo
20.
J Clin Lab Anal ; 36(9): e24647, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35949045

RESUMO

BACKGROUND: Kinesin family member 2A (KIF2A), nuclear division cycle 80 (NDC80), cyclin-dependent kinase 1 (CDK1), and cyclin B1 (CCNB1) exhibit a complex interrelation, which promote cancer progression via multiple ways, whereas their interaction and clinical implications in breast cancer are obscure. Hence, this study aimed to evaluate the correlation among KIF2A, NDC80, CDK1, CCNB1, and their linkage with clinicopathological features and prognosis in breast cancer patients. METHODS: 195 breast cancer patients underwent surgical resection were analyzed. KIF2A, NDC80, CDK1, and CCNB1 expressions were determined by immunohistochemical (IHC) assay and scored by a semiquantitative IHC score or positive cell percentage. RESULTS: KIF2A expression positively associated with NDC80, CDK1, and CCNB1 expressions (all p < 0.01). In terms of tumor features: KIF2A high expression linked with increased T stage (p = 0.011), N stage (p = 0.014), and TNM stage (p = 0.009) but not tumor differentiation (p = 0.651). NDC80 high expression only related to higher N stage (p = 0.010); CDK1 high expression only connected with elevated N stage (p = 0.035) and TNM stage (p = 0.023). In aspect of prognosis, high expression of KIF2A was correlated with worse disease-free survival (DFS) (p = 0.031), while NDC80 high (p = 0.329), CDK1 high (p = 0.276), and CCNB1 positive (p = 0.063) expressions only showed trends to link with poor DFS (without statistical significance). Furthermore, high expression of KIF2A (p = 0.063), NDC80 (p = 0.939), CDK1 (p = 0.413) and positive expression of CCNB1 (p = 0.296) did not relate to overall survival. CONCLUSION: KIF2A correlates with NDC80, CDK1, CCNB1, and may link with advanced tumor stages and poor prognosis in breast cancer patients.


Assuntos
Neoplasias da Mama , Proteína Quinase CDC2 , Neoplasias da Mama/patologia , Divisão do Núcleo Celular , Ciclina B1/genética , Proteínas do Citoesqueleto , Feminino , Humanos , Cinesinas , Prognóstico
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