Taxol- and baccatin III-induced apoptosis in Jurkat cells assayed with PI staining followed by flow cytometry. Cells (0.25 × 106) were treated with indicated concentrations of taxol or baccatin III for 48 h, and analyzed by PI staining followed by flow cytometry to determine the hypodiploid DNA (fragmented DNA) proportions. 1 × 105 cells were analyzed. The percentage of hypodiploid cells (sub G1 peak) was calculated on the basis of the respective histograms. UT, Untreated cells; DMSO, Dimethylsulfoxide; TSTD, standard taxol; TFUNG, fungal taxol; BSTD, standard baccatin III; BFUNG, fungal baccatin III.