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Mitotic Stress Is an Integral Part of the Oncogene-Induced Senescence Program that Promotes Multinucleation and Cell Cycle Arrest.

Dikovskaya D, Cole JJ, Mason SM, Nixon C, Karim SA, McGarry L, Clark W, Hewitt RN, Sammons MA, Zhu J, Athineos D, Leach JD, Marchesi F, van Tuyn J, Tait SW, Brock C, Morton JP, Wu H, Berger SL, Blyth K, Adams PD - Cell Rep (2015)

Bottom Line: ERK-dependent transcriptional upregulation of Mcl1 was, at least in part, responsible for enhanced survival and slippage of cells with mitotic defects.Importantly, mitotic slippage and oncogene signaling cooperatively induced senescence and key senescence effectors p21 and p16.In summary, activated Ras coordinately triggers mitotic disruption and enhanced cell survival to promote formation of multinucleate senescent cells.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cancer Sciences, CR-UK Beatson Laboratories, University of Glasgow, Glasgow G61 1BD, UK. Electronic address: ddikovskaya@gmail.com.

No MeSH data available.


Related in: MedlinePlus

Mitotic Abnormalities in Pre-senescent Cells with Activated H-RasV12(A) Mitotic spindles in control (top, Cntr) and induced (bottom, Ras) ERRAS cells, stained for microtubules (left panels, red in overlay) or DAPI (blue in overlay). Scale bars, 20 μm.(B) Quantification of chromatin and spindle defects (exemplified in A and D) in prometaphases (prometa) and metaphases (meta) of control (Cntr) or 5-day-induced (Ras) ERRAS cells. Data indicate means ± SD and p values from three replicates, 53–65 mitoses each.(C and D) Normal mitotic chromatin (C) or Ras-induced chromatin defect (D) in mitotic cells from prophase to metaphase. Single optical sections of 3D confocal images of control (Cntr) (C) or 3-day-induced ERRAS (D) cells stained for microtubules (left panels, red in overlay) or DAPI (middle panels, blue in overlay). Scale bars, 2 μm. Yellow frames show the visible width of chromosomes.(E) Quantification of chromatin decompaction in high-resolution 3D confocal images in two independent experiments. DAPI-stained prometaphases (prometa) and metaphases (meta) in control (Cntr) or 3-day-induced (Ras) ERRAS cells were scored for decompacted (decomp), partially decompacted (mixed), or normal chromatin (normal). Two independent experiments are shown. 15–26 mitoses per condition per experiment. p values for distribution changes calculated with two-way ANOVA.(F) Normal anaphase (left), aberrant anaphase with bridge (middle), or anaphase with a lagging chromosome (right). Scale bars, 10 μm.(G) Quantification of anaphase defects, shown in (F), in 3- and 4-day-induced (Ras) or control (Cntr) ERRAS cells. Data indicate means ± SD and p values from three replicas, 155–532 anaphases each.
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fig2: Mitotic Abnormalities in Pre-senescent Cells with Activated H-RasV12(A) Mitotic spindles in control (top, Cntr) and induced (bottom, Ras) ERRAS cells, stained for microtubules (left panels, red in overlay) or DAPI (blue in overlay). Scale bars, 20 μm.(B) Quantification of chromatin and spindle defects (exemplified in A and D) in prometaphases (prometa) and metaphases (meta) of control (Cntr) or 5-day-induced (Ras) ERRAS cells. Data indicate means ± SD and p values from three replicates, 53–65 mitoses each.(C and D) Normal mitotic chromatin (C) or Ras-induced chromatin defect (D) in mitotic cells from prophase to metaphase. Single optical sections of 3D confocal images of control (Cntr) (C) or 3-day-induced ERRAS (D) cells stained for microtubules (left panels, red in overlay) or DAPI (middle panels, blue in overlay). Scale bars, 2 μm. Yellow frames show the visible width of chromosomes.(E) Quantification of chromatin decompaction in high-resolution 3D confocal images in two independent experiments. DAPI-stained prometaphases (prometa) and metaphases (meta) in control (Cntr) or 3-day-induced (Ras) ERRAS cells were scored for decompacted (decomp), partially decompacted (mixed), or normal chromatin (normal). Two independent experiments are shown. 15–26 mitoses per condition per experiment. p values for distribution changes calculated with two-way ANOVA.(F) Normal anaphase (left), aberrant anaphase with bridge (middle), or anaphase with a lagging chromosome (right). Scale bars, 10 μm.(G) Quantification of anaphase defects, shown in (F), in 3- and 4-day-induced (Ras) or control (Cntr) ERRAS cells. Data indicate means ± SD and p values from three replicas, 155–532 anaphases each.

Mentions: Consistent with observed mitotic failure in induced ERRAS cells, we found a significant increase in spindle defects (Figures 2A and 2B) and abnormal chromatin morphology (Figures 2B–2E) in prometaphase and metaphase cells 3–5 days after Ras activation. Specifically, mitotic spindles were either misshapen or had low microtubule content (Figure 2A; data not shown), and prometaphase and metaphase chromatin appeared de-compacted (Figures 2C–2E; compare the diameters of individual chromosomes indicated in Figures 2C and 2D). Furthermore, the proportion of anaphases with either lagging chromosomes or anaphase bridges (Figure 2F) was significantly higher in cells after Ras activation (Figure 2G). Thus, H-RasV12 activation triggers mitotic abnormalities in primary human fibroblasts.


Mitotic Stress Is an Integral Part of the Oncogene-Induced Senescence Program that Promotes Multinucleation and Cell Cycle Arrest.

Dikovskaya D, Cole JJ, Mason SM, Nixon C, Karim SA, McGarry L, Clark W, Hewitt RN, Sammons MA, Zhu J, Athineos D, Leach JD, Marchesi F, van Tuyn J, Tait SW, Brock C, Morton JP, Wu H, Berger SL, Blyth K, Adams PD - Cell Rep (2015)

Mitotic Abnormalities in Pre-senescent Cells with Activated H-RasV12(A) Mitotic spindles in control (top, Cntr) and induced (bottom, Ras) ERRAS cells, stained for microtubules (left panels, red in overlay) or DAPI (blue in overlay). Scale bars, 20 μm.(B) Quantification of chromatin and spindle defects (exemplified in A and D) in prometaphases (prometa) and metaphases (meta) of control (Cntr) or 5-day-induced (Ras) ERRAS cells. Data indicate means ± SD and p values from three replicates, 53–65 mitoses each.(C and D) Normal mitotic chromatin (C) or Ras-induced chromatin defect (D) in mitotic cells from prophase to metaphase. Single optical sections of 3D confocal images of control (Cntr) (C) or 3-day-induced ERRAS (D) cells stained for microtubules (left panels, red in overlay) or DAPI (middle panels, blue in overlay). Scale bars, 2 μm. Yellow frames show the visible width of chromosomes.(E) Quantification of chromatin decompaction in high-resolution 3D confocal images in two independent experiments. DAPI-stained prometaphases (prometa) and metaphases (meta) in control (Cntr) or 3-day-induced (Ras) ERRAS cells were scored for decompacted (decomp), partially decompacted (mixed), or normal chromatin (normal). Two independent experiments are shown. 15–26 mitoses per condition per experiment. p values for distribution changes calculated with two-way ANOVA.(F) Normal anaphase (left), aberrant anaphase with bridge (middle), or anaphase with a lagging chromosome (right). Scale bars, 10 μm.(G) Quantification of anaphase defects, shown in (F), in 3- and 4-day-induced (Ras) or control (Cntr) ERRAS cells. Data indicate means ± SD and p values from three replicas, 155–532 anaphases each.
© Copyright Policy - CC BY
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4562906&req=5

fig2: Mitotic Abnormalities in Pre-senescent Cells with Activated H-RasV12(A) Mitotic spindles in control (top, Cntr) and induced (bottom, Ras) ERRAS cells, stained for microtubules (left panels, red in overlay) or DAPI (blue in overlay). Scale bars, 20 μm.(B) Quantification of chromatin and spindle defects (exemplified in A and D) in prometaphases (prometa) and metaphases (meta) of control (Cntr) or 5-day-induced (Ras) ERRAS cells. Data indicate means ± SD and p values from three replicates, 53–65 mitoses each.(C and D) Normal mitotic chromatin (C) or Ras-induced chromatin defect (D) in mitotic cells from prophase to metaphase. Single optical sections of 3D confocal images of control (Cntr) (C) or 3-day-induced ERRAS (D) cells stained for microtubules (left panels, red in overlay) or DAPI (middle panels, blue in overlay). Scale bars, 2 μm. Yellow frames show the visible width of chromosomes.(E) Quantification of chromatin decompaction in high-resolution 3D confocal images in two independent experiments. DAPI-stained prometaphases (prometa) and metaphases (meta) in control (Cntr) or 3-day-induced (Ras) ERRAS cells were scored for decompacted (decomp), partially decompacted (mixed), or normal chromatin (normal). Two independent experiments are shown. 15–26 mitoses per condition per experiment. p values for distribution changes calculated with two-way ANOVA.(F) Normal anaphase (left), aberrant anaphase with bridge (middle), or anaphase with a lagging chromosome (right). Scale bars, 10 μm.(G) Quantification of anaphase defects, shown in (F), in 3- and 4-day-induced (Ras) or control (Cntr) ERRAS cells. Data indicate means ± SD and p values from three replicas, 155–532 anaphases each.
Mentions: Consistent with observed mitotic failure in induced ERRAS cells, we found a significant increase in spindle defects (Figures 2A and 2B) and abnormal chromatin morphology (Figures 2B–2E) in prometaphase and metaphase cells 3–5 days after Ras activation. Specifically, mitotic spindles were either misshapen or had low microtubule content (Figure 2A; data not shown), and prometaphase and metaphase chromatin appeared de-compacted (Figures 2C–2E; compare the diameters of individual chromosomes indicated in Figures 2C and 2D). Furthermore, the proportion of anaphases with either lagging chromosomes or anaphase bridges (Figure 2F) was significantly higher in cells after Ras activation (Figure 2G). Thus, H-RasV12 activation triggers mitotic abnormalities in primary human fibroblasts.

Bottom Line: ERK-dependent transcriptional upregulation of Mcl1 was, at least in part, responsible for enhanced survival and slippage of cells with mitotic defects.Importantly, mitotic slippage and oncogene signaling cooperatively induced senescence and key senescence effectors p21 and p16.In summary, activated Ras coordinately triggers mitotic disruption and enhanced cell survival to promote formation of multinucleate senescent cells.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cancer Sciences, CR-UK Beatson Laboratories, University of Glasgow, Glasgow G61 1BD, UK. Electronic address: ddikovskaya@gmail.com.

No MeSH data available.


Related in: MedlinePlus