<p>S1. Post-slippage cells arrest at G1 as tetraploid multinucleated cells. S2. Correlation of multinucleation and senescence post-slippage in response to various anti-mitotic drugs. S3. In vivo association of senescence and anti-mitotic drug treatment. S4. Post-slippage cells increase expression of factors associated with senescence and SASP. S5. SASP factors from post-slippage cells do not affect proliferation of neighbouring cells. S6. Autophagy mediates senescence. S7. Autophagy does not modulate cell fate during prolonged mitotic arrest. S8. Autophagy-dependent IL-1β and IL-8 expression mediate cell invasiveness in a paracrine manner. S9. Silencing of p53 increases post-slippage cell death. S10. p53 status determines synergistic effect of microtubule poisons and autophagy inhibition. Table S1. List of differentially regulated proteins after 48 h Noc treatment detected by SILAC mass spectrometry. Table S2. List of antibodies. Table S3. List of chemicals. Table S4. List of primers. Table S5. Quantitative H scoring method</p>
Chromosomal instability (CIN), a high rate of chromosome loss or gain, is often associated with poor prognosis and drug resistance in cancers. Aneuploid, including near-polyploid, cells contain an abnormal number of chromosomes and exhibit CIN. The post-mitotic cell fates following generation of different degrees of chromosome mis-segregation and aneuploidy are unclear. Here we used aneuploidy inducers, nocodazole and reversine, to create different levels of aneuploidy. A higher extent of aneuploid and near-polyploid cells in a given population led to senescence. This was in contrast to cells with relatively lower levels of abnormal ploidy that continued to proliferate. Our findings revealed that senescence was accompanied by DNA damage and robust p53 activation. These senescent cells acquired the senescence-associated secretory phenotype (SASP). Depletion of p53 reduced the number of senescent cells with concomitant increase in cells undergoing DNA replication. Characterisation of these SASP factors demonstrated that they conferred paracrine pro-tumourigenic effects such as invasion, migration and angiogenesis both in vitro and in vivo. Finally, a correlation between increased aneuploidy and senescence was observed at the invasive front in breast carcinomas. Our findings demonstrate functional non-equivalence of discernable aneuploidies on tumourigenesis and suggest a cell non-autonomous mechanism by which aneuploidy-induced senescent cells and SASP can affect the tumour microenvironment to promote tumour progression.
<p>S1. Post-slippage cells arrest at G1 as tetraploid multinucleated cells. S2. Correlation of multinucleation and senescence post-slippage in response to various anti-mitotic drugs. S3. In vivo association of senescence and anti-mitotic drug treatment. S4. Post-slippage cells increase expression of factors associated with senescence and SASP. S5. SASP factors from post-slippage cells do not affect proliferation of neighbouring cells. S6. Autophagy mediates senescence. S7. Autophagy does not modulate cell fate during prolonged mitotic arrest. S8. Autophagy-dependent IL-1β and IL-8 expression mediate cell invasiveness in a paracrine manner. S9. Silencing of p53 increases post-slippage cell death. S10. p53 status determines synergistic effect of microtubule poisons and autophagy inhibition. Table S1. List of differentially regulated proteins after 48 h Noc treatment detected by SILAC mass spectrometry. Table S2. List of antibodies. Table S3. List of chemicals. Table S4. List of primers. Table S5. Quantitative H scoring method</p>