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Long-term Live-cell Imaging to Assess Cell Fate in Response to Paclitaxel
08:29

Long-term Live-cell Imaging to Assess Cell Fate in Response to Paclitaxel

Published on: May 14, 2018

Cellular senescence induced by aberrant MAD2 levels impacts on paclitaxel responsiveness in vitro

M Prencipe1, P Fitzpatrick, S Gorman

  • 1UCD School of Medicine and Medical Science (SMMS), University College Dublin, UCD, Belfield, Dublin 4, Ireland. maria.prencipe@ucd.ie

British Journal of Cancer
|November 26, 2009
PubMed
Abstract

Insights

Down-regulating MAD2 (mitotic arrest deficiency protein 2) triggers premature cellular senescence in breast cancer cells. These senescent cells evade paclitaxel chemotherapy, highlighting a new resistance mechanism.

Area of Science:

  • Cell Biology
  • Cancer Research
  • Molecular Biology

Background:

  • Mitotic arrest deficiency protein 2 (MAD2) is crucial for the spindle assembly checkpoint during mitosis.
  • MAD2 also influences cellular senescence and response to microtubule-targeting chemotherapy like paclitaxel.

Purpose of the Study:

  • To investigate the impact of MAD2 down-regulation on cellular senescence.
  • To determine how MAD2 depletion affects responsiveness to paclitaxel chemotherapy.

Main Methods:

  • Utilized siRNA to reduce MAD2 levels in MCF7 breast cancer cells.
  • Assessed senescence, cell viability, migration, cytokine secretion (IL-6, IL-8), cell cycle, and anaphase bridges.

Main Results:

  • MAD2 depletion induced premature senescence, replicative incompetence, and polyploidy in MCF7 cells.
  • MAD2-depleted cells exhibited increased senescence-associated secretory phenotype (SASP) with higher IL-6/IL-8 levels and enhanced migration.
  • These senescent cells showed increased viability and further senescence induction after paclitaxel treatment.

Conclusions:

  • Compromised MAD2 levels generate a senescent cell population resistant to paclitaxel.
  • Senescent cells evade cytotoxic effects of paclitaxel, suggesting MAD2's role in chemotherapy resistance.

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