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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

Increased Mcl1 Is Responsible for H-RasV12-Enhanced Mitotic Slippage(A) Mcl1 depletion by siRNA in control (Cntr) or induced (Ras) ERRAS cells. siC, non-targeting siRNA; siM, Mcl1-targeting siRNA; -, no transfection. Actin is a loading control.(B) Time-lapse analysis of duration and outcome of individual mitoses in control (Cntr) or 4-day-induced (Ras) ERRAS cells transfected with either Mcl1-targeting (siM) or non-targeting (siC) siRNA, treated with DME for 3 days. 207–337 mitoses per condition. Percentage of slippage is shown at top.(C) Percentage of mitotic slippage quantified from (B). Data indicate mean ± SEM from three biological replicates, 63–115 mitoses each.(D) Mcl1 level in ERRAS cells infected with retrovirus expressing HA-Mcl1 or vector only. Actin is a loading control.(E) Time-lapse analysis of duration and outcome of individual mitoses in DME-treated HA-Mcl1 or vector-expressing uninduced ERRAS cells, 141–165 mitoses per condition.(F) Percentage of mitotic slippage quantified from (E). Data indicate mean ± SEM from three replicates, 43–61 mitoses each.
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fig5: Increased Mcl1 Is Responsible for H-RasV12-Enhanced Mitotic Slippage(A) Mcl1 depletion by siRNA in control (Cntr) or induced (Ras) ERRAS cells. siC, non-targeting siRNA; siM, Mcl1-targeting siRNA; -, no transfection. Actin is a loading control.(B) Time-lapse analysis of duration and outcome of individual mitoses in control (Cntr) or 4-day-induced (Ras) ERRAS cells transfected with either Mcl1-targeting (siM) or non-targeting (siC) siRNA, treated with DME for 3 days. 207–337 mitoses per condition. Percentage of slippage is shown at top.(C) Percentage of mitotic slippage quantified from (B). Data indicate mean ± SEM from three biological replicates, 63–115 mitoses each.(D) Mcl1 level in ERRAS cells infected with retrovirus expressing HA-Mcl1 or vector only. Actin is a loading control.(E) Time-lapse analysis of duration and outcome of individual mitoses in DME-treated HA-Mcl1 or vector-expressing uninduced ERRAS cells, 141–165 mitoses per condition.(F) Percentage of mitotic slippage quantified from (E). Data indicate mean ± SEM from three replicates, 43–61 mitoses each.

Mentions: To test the requirement for a high level of Mcl1 in Ras-induced resistance to mitotic death, we depleted Mcl1 from control and induced ERRAS cells using small interfering RNA (siRNA) (Figure 5A). Tracking individual mitoses in time-lapse images revealed that depletion of Mcl1 reduced slippage out of DME-induced mitotic arrest and increased mitotic cell death (Figures 5B and 5C). Furthermore, ectopic expression of Mcl1 (Figure 5D) in control cells increased slippage and reduced death in DME-treated cells (Figures 5E and 5F), recapitulating the effect of Ras activation. Thus, in ERRAS cells, Ras-mediated upregulation of Mcl1 is necessary and sufficient for enhanced survival and increased slippage of damaged mitoses, contributing to generation of MNCs by activated H-RasV12.


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)

Increased Mcl1 Is Responsible for H-RasV12-Enhanced Mitotic Slippage(A) Mcl1 depletion by siRNA in control (Cntr) or induced (Ras) ERRAS cells. siC, non-targeting siRNA; siM, Mcl1-targeting siRNA; -, no transfection. Actin is a loading control.(B) Time-lapse analysis of duration and outcome of individual mitoses in control (Cntr) or 4-day-induced (Ras) ERRAS cells transfected with either Mcl1-targeting (siM) or non-targeting (siC) siRNA, treated with DME for 3 days. 207–337 mitoses per condition. Percentage of slippage is shown at top.(C) Percentage of mitotic slippage quantified from (B). Data indicate mean ± SEM from three biological replicates, 63–115 mitoses each.(D) Mcl1 level in ERRAS cells infected with retrovirus expressing HA-Mcl1 or vector only. Actin is a loading control.(E) Time-lapse analysis of duration and outcome of individual mitoses in DME-treated HA-Mcl1 or vector-expressing uninduced ERRAS cells, 141–165 mitoses per condition.(F) Percentage of mitotic slippage quantified from (E). Data indicate mean ± SEM from three replicates, 43–61 mitoses each.
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fig5: Increased Mcl1 Is Responsible for H-RasV12-Enhanced Mitotic Slippage(A) Mcl1 depletion by siRNA in control (Cntr) or induced (Ras) ERRAS cells. siC, non-targeting siRNA; siM, Mcl1-targeting siRNA; -, no transfection. Actin is a loading control.(B) Time-lapse analysis of duration and outcome of individual mitoses in control (Cntr) or 4-day-induced (Ras) ERRAS cells transfected with either Mcl1-targeting (siM) or non-targeting (siC) siRNA, treated with DME for 3 days. 207–337 mitoses per condition. Percentage of slippage is shown at top.(C) Percentage of mitotic slippage quantified from (B). Data indicate mean ± SEM from three biological replicates, 63–115 mitoses each.(D) Mcl1 level in ERRAS cells infected with retrovirus expressing HA-Mcl1 or vector only. Actin is a loading control.(E) Time-lapse analysis of duration and outcome of individual mitoses in DME-treated HA-Mcl1 or vector-expressing uninduced ERRAS cells, 141–165 mitoses per condition.(F) Percentage of mitotic slippage quantified from (E). Data indicate mean ± SEM from three replicates, 43–61 mitoses each.
Mentions: To test the requirement for a high level of Mcl1 in Ras-induced resistance to mitotic death, we depleted Mcl1 from control and induced ERRAS cells using small interfering RNA (siRNA) (Figure 5A). Tracking individual mitoses in time-lapse images revealed that depletion of Mcl1 reduced slippage out of DME-induced mitotic arrest and increased mitotic cell death (Figures 5B and 5C). Furthermore, ectopic expression of Mcl1 (Figure 5D) in control cells increased slippage and reduced death in DME-treated cells (Figures 5E and 5F), recapitulating the effect of Ras activation. Thus, in ERRAS cells, Ras-mediated upregulation of Mcl1 is necessary and sufficient for enhanced survival and increased slippage of damaged mitoses, contributing to generation of MNCs by activated H-RasV12.

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