Taxol-induced paraptosis-like A549 cell death is not senescence

摘要

Our previous studies have shown that taxol, a potent anticancer agent, induces caspase-independent cell death and cytoplasmic vacuolization in human lung cancer cells. However, the mechanisms of taxol-induced cytoplasmic vacuolization are poorly understood. Cytoplasmic vacuolization have been reported to be a characteristic of cell senescence. Here, we employed confocal fluorescence microscopy imaging to study the reversibility of taxol-induced cytoplasmic vacuolization and whether taxol triggers senescence in A549 cells. We found that taxol-induced cytoplasmic vacuolization at 6 or 9 h after treatment with taxol did not decrease but increase at 24 h or 72 h after refreshing the culture medium without taxol, indicating taxol-induced cytoplasmic vacuolization is irreversible. We used SA-P-Gal (senescence-associated P-galactosidase) to assess whether taxol-induced cell death in cytoplasmic vacuolization fashion is senescence, and found that hydrogen peroxide (H_2O_2)-treated, but not taxol-treated cells is significantly stained by the SA-(3-Gal, a senescence testing kit, indicating that the form of taxol-induced cell death is not senescence.