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Molecular Biology Reports Nov 2022The process of cell division plays a vital role in cancer progression. Cell proliferation and error-free chromosomes segregation during mitosis are central events in... (Review)
Review
The process of cell division plays a vital role in cancer progression. Cell proliferation and error-free chromosomes segregation during mitosis are central events in life cycle. Mistakes during cell division generate changes in chromosome content and alter the balances of chromosomes number. Any defects in expression of TIF1 family proteins, SAC proteins network, mitotic checkpoint proteins involved in chromosome mis-segregation and cancer development. Here we discuss the function of organelles deal with the chromosome segregation machinery, proteins and correction mechanisms involved in the accurate chromosome segregation during mitosis.
Topics: Humans; Chromosome Segregation; Mitosis; Cell Cycle; M Phase Cell Cycle Checkpoints; Cell Cycle Proteins; Neoplasms; Kinetochores
PubMed: 35931874
DOI: 10.1007/s11033-022-07788-1 -
Methods in Molecular Biology (Clifton,... 2022The cell cycle is the series of events that take place in a cell that drives it to divide and produce two new daughter cells. Through more than 100 years of efforts by... (Review)
Review
The cell cycle is the series of events that take place in a cell that drives it to divide and produce two new daughter cells. Through more than 100 years of efforts by scientists, we now have a much clearer picture of cell cycle progression and its regulation. The typical cell cycle in eukaryotes is composed of the G1, S, G2, and M phases. The M phase is further divided into prophase, prometaphase, metaphase, anaphase, telophase, and cytokinesis. Cell cycle progression is mediated by cyclin-dependent kinases (Cdks) and their regulatory cyclin subunits. However, the driving force of cell cycle progression is growth factor-initiated signaling pathways that controls the activity of various Cdk-cyclin complexes. Most cellular events, including DNA duplication, gene transcription, protein translation, and post-translational modification of proteins, occur in a cell-cycle-dependent manner. To understand these cellular events and their underlying molecular mechanisms, it is desirable to have a population of cells that are traversing the cell cycle synchronously. This can be achieved through a process called cell synchronization. Many methods have been developed to synchronize cells to the various phases of the cell cycle. These methods could be classified into two groups: synchronization methods using chemical inhibitors and synchronization methods without using chemical inhibitors. All these methods have their own merits and shortcomings.
Topics: Anaphase; Cell Cycle; Cell Cycle Proteins; Cyclin-Dependent Kinases; Cyclins; Mitosis
PubMed: 36045194
DOI: 10.1007/978-1-0716-2736-5_1 -
Cells Aug 2022Cell cycle and cell adhesion are two interdependent cellular processes regulating each other, reciprocally, in every cell cycle phase. The cell adhesion to the... (Review)
Review
Cell cycle and cell adhesion are two interdependent cellular processes regulating each other, reciprocally, in every cell cycle phase. The cell adhesion to the extracellular matrix (ECM) via integrin receptors triggers signaling pathways required for the cell cycle progression; the passage from the G1 to S phase and the completion of cytokinesis are the best-understood events. Growing evidence, however, suggests more adhesion-dependent regulatory aspects of the cell cycle, particularly during G2 to M transition and early mitosis. Conversely, the cell cycle machinery regulates cell adhesion in manners recently shown driven mainly by cyclin-dependent kinase 1 (CDK1). This review summarizes the recent findings regarding the role of integrin-mediated cell adhesion and its downstream signaling components in regulating the cell cycle, emphasizing the cell cycle progression through the G2 and early M phases. Further investigations are required to raise our knowledge about the molecular mechanisms of crosstalk between cell adhesion and the cell cycle in detail.
Topics: Cell Adhesion; Cell Cycle; Cell Cycle Checkpoints; Integrins; Mitosis
PubMed: 36010598
DOI: 10.3390/cells11162521 -
Science (New York, N.Y.) Aug 2023Nonhomologous end-joining (NHEJ) and homologous recombination (HR) are the primary pathways for repairing DNA double-strand breaks (DSBs) during interphase, whereas...
Nonhomologous end-joining (NHEJ) and homologous recombination (HR) are the primary pathways for repairing DNA double-strand breaks (DSBs) during interphase, whereas microhomology-mediated end-joining (MMEJ) has been regarded as a backup mechanism. Through CRISPR-Cas9-based synthetic lethal screens in cancer cells, we identified subunits of the 9-1-1 complex (RAD9A-RAD1-HUS1) and its interacting partner, RHINO, as crucial MMEJ factors. We uncovered an unexpected function for RHINO in restricting MMEJ to mitosis. RHINO accumulates in M phase, undergoes Polo-like kinase 1 (PLK1) phosphorylation, and interacts with polymerase θ (Polθ), enabling its recruitment to DSBs for subsequent repair. Additionally, we provide evidence that MMEJ activity in mitosis repairs persistent DSBs that originate in S phase. Our findings offer insights into the synthetic lethal relationship between the genes and and and the synergistic effect of Polθ and poly(ADP-ribose) polymerase (PARP) inhibitors.
Topics: Humans; Cell Cycle Proteins; DNA Breaks, Double-Stranded; DNA End-Joining Repair; Exonucleases; HEK293 Cells; Mitosis; Poly(ADP-ribose) Polymerases
PubMed: 37440612
DOI: 10.1126/science.adh3694 -
The Journal of Cell Biology May 2023Enduring chromosome segregation errors represent potential threats to genomic stability due to eventual chromosome copy number alterations (aneuploidy) and formation of... (Review)
Review
Enduring chromosome segregation errors represent potential threats to genomic stability due to eventual chromosome copy number alterations (aneuploidy) and formation of micronuclei-key intermediates of a rapid mutational process known as chromothripsis that is found in cancer and congenital disorders. The spindle assembly checkpoint (SAC) has been viewed as the sole surveillance mechanism that prevents chromosome segregation errors during mitosis and meiosis. However, different types of chromosome segregation errors stemming from incorrect kinetochore-microtubule attachments satisfy the SAC and are more frequent than previously anticipated. Remarkably, recent works have unveiled that most of these errors are corrected during anaphase and only rarely result in aneuploidy or formation of micronuclei. Here, we discuss recent progress in our understanding of the origin and fate of chromosome segregation errors that satisfy the SAC and shed light on the surveillance, correction, and clearance mechanisms that prevent their transmission, to preserve genomic stability.
Topics: Humans; Anaphase; Aneuploidy; Chromosome Segregation; Kinetochores; Microtubules; Mitosis; Spindle Apparatus; Genomic Instability
PubMed: 37017932
DOI: 10.1083/jcb.202301106 -
Nature Apr 2023Lactate is abundant in rapidly dividing cells owing to the requirement for elevated glucose catabolism to support proliferation. However, it is not known whether...
Lactate is abundant in rapidly dividing cells owing to the requirement for elevated glucose catabolism to support proliferation. However, it is not known whether accumulated lactate affects the proliferative state. Here we use a systematic approach to determine lactate-dependent regulation of proteins across the human proteome. From these data, we identify a mechanism of cell cycle regulation whereby accumulated lactate remodels the anaphase promoting complex (APC/C). Remodelling of APC/C in this way is caused by direct inhibition of the SUMO protease SENP1 by lactate. We find that accumulated lactate binds and inhibits SENP1 by forming a complex with zinc in the SENP1 active site. SENP1 inhibition by lactate stabilizes SUMOylation of two residues on APC4, which drives UBE2C binding to APC/C. This direct regulation of APC/C by lactate stimulates timed degradation of cell cycle proteins, and efficient mitotic exit in proliferative human cells. This mechanism is initiated upon mitotic entry when lactate abundance reaches its apex. In this way, accumulation of lactate communicates the consequences of a nutrient-replete growth phase to stimulate timed opening of APC/C, cell division and proliferation. Conversely, persistent accumulation of lactate drives aberrant APC/C remodelling and can overcome anti-mitotic pharmacology via mitotic slippage. In sum, we define a biochemical mechanism through which lactate directly regulates protein function to control the cell cycle and proliferation.
Topics: Humans; Anaphase; Anaphase-Promoting Complex-Cyclosome; Cell Cycle; Cell Cycle Proteins; Lactic Acid; Mitosis
PubMed: 36921622
DOI: 10.1038/s41586-023-05939-3 -
Science (New York, N.Y.) Mar 2024Mitotic duration is tightly constrained, and extended mitosis is characteristic of problematic cells prone to chromosome missegregation and genomic instability. We show...
Mitotic duration is tightly constrained, and extended mitosis is characteristic of problematic cells prone to chromosome missegregation and genomic instability. We show here that mitotic extension leads to the formation of p53-binding protein 1 (53BP1)-ubiquitin-specific protease 28 (USP28)-p53 protein complexes that are transmitted to, and stably retained by, daughter cells. Complexes assembled through a Polo-like kinase 1-dependent mechanism during extended mitosis and elicited a p53 response in G that prevented the proliferation of the progeny of cells that experienced an approximately threefold extended mitosis or successive less extended mitoses. The ability to monitor mitotic extension was lost in p53-mutant cancers and some p53-wild-type (p53-WT) cancers, consistent with classification of and as tumor suppressors. Cancers retaining the ability to monitor mitotic extension exhibited sensitivity to antimitotic agents.
Topics: Humans; Cell Proliferation; Genomic Instability; Mitosis; Neoplasms; Tumor Suppressor Protein p53; Ubiquitin Thiolesterase; Tumor Suppressor p53-Binding Protein 1; Cell Line, Tumor; Polo-Like Kinase 1; Antimitotic Agents; Drug Resistance, Neoplasm
PubMed: 38547292
DOI: 10.1126/science.add9528 -
Methods in Molecular Biology (Clifton,... 2023Cellular division is a fundamental process of cellular growth. First, cells replicate their DNA in S phase and then undergo mitosis which, under normal conditions, leads...
Cellular division is a fundamental process of cellular growth. First, cells replicate their DNA in S phase and then undergo mitosis which, under normal conditions, leads to complete cell division. Moreover, mitotic activity correlates to cellular growth activity. The simplest and classical method to measure mitotic activity (mitotic index (MI)), is the manual counting of mitotic cells among a given cell population of interest. The latter can be accomplished via phase contrast microscope observation. However, Giemsa staining may improve accuracy and consistency. Fluorescence immunostaining targeting specific phosphorylations of proteins at critical cell cycle steps will provide further improved analysis via high-throughput capacity of flow or imaging cytometer. Finally, time lapse image analysis provides quantitative and qualitative metrics delineating the process of cellular division including timing of division, duration of mitosis, and failure to procced through or complete mitosis.
Topics: Cell Cycle; Mitosis; Mitotic Index; Phosphorylation; S Phase
PubMed: 36066706
DOI: 10.1007/978-1-0716-2433-3_3 -
Nature Feb 2021Whole-genome doubling (WGD) is common in human cancers, occurring early in tumorigenesis and generating genetically unstable tetraploid cells that fuel tumour...
Whole-genome doubling (WGD) is common in human cancers, occurring early in tumorigenesis and generating genetically unstable tetraploid cells that fuel tumour development. Cells that undergo WGD (WGD cells) must adapt to accommodate their abnormal tetraploid state; however, the nature of these adaptations, and whether they confer vulnerabilities that can be exploited therapeutically, is unclear. Here, using sequencing data from roughly 10,000 primary human cancer samples and essentiality data from approximately 600 cancer cell lines, we show that WGD gives rise to common genetic traits that are accompanied by unique vulnerabilities. We reveal that WGD cells are more dependent than WGD cells on signalling from the spindle-assembly checkpoint, DNA-replication factors and proteasome function. We also identify KIF18A, which encodes a mitotic kinesin protein, as being specifically required for the viability of WGD cells. Although KIF18A is largely dispensable for accurate chromosome segregation during mitosis in WGD cells, its loss induces notable mitotic errors in WGD cells, ultimately impairing cell viability. Collectively, our results suggest new strategies for specifically targeting WGD cancer cells while sparing the normal, non-transformed WGD cells that comprise human tissue.
Topics: Abnormal Karyotype; Breast Neoplasms; Cell Line, Tumor; Female; Genes, Lethal; Genome, Human; Humans; Kinesins; M Phase Cell Cycle Checkpoints; Male; Mitosis; Neoplasms; Proteasome Endopeptidase Complex; Reproducibility of Results; Spindle Apparatus; Tetraploidy
PubMed: 33505027
DOI: 10.1038/s41586-020-03133-3 -
Journal of Cell Science Sep 2020Human retinal pigment epithelial-1 (RPE-1) cells are increasingly being used as a model to study mitosis because they represent a non-transformed alternative to cancer...
Human retinal pigment epithelial-1 (RPE-1) cells are increasingly being used as a model to study mitosis because they represent a non-transformed alternative to cancer cell lines, such as HeLa cervical adenocarcinoma cells. However, the lack of an efficient method to synchronize RPE-1 cells in mitosis precludes their application for large-scale biochemical and proteomics assays. Here, we report a protocol to synchronize RPE-1 cells based on sequential treatments with the Cdk4 and Cdk6 inhibitor PD 0332991 (palbociclib) and the microtubule-depolymerizing drug nocodazole. With this method, the vast majority (80-90%) of RPE-1 cells arrested at prometaphase and exited mitosis synchronously after release from nocodazole. Moreover, the cells fully recovered and re-entered the cell cycle after the palbociclib-nocodazole block. Finally, we show that this protocol could be successfully employed for the characterization of the protein-protein interaction network of the kinetochore protein Ndc80 by immunoprecipitation coupled with mass spectrometry. This synchronization method significantly expands the versatility and applicability of RPE-1 cells to the study of cell division and might be applied to other cell lines that do not respond to treatments with DNA synthesis inhibitors.
Topics: Humans; Kinetochores; Mitosis; Nocodazole; Prometaphase; Retinal Pigments
PubMed: 32878943
DOI: 10.1242/jcs.247940