Figure 3
(A) Effect of natural and synthetic 1 on HCT-116 colony formation at GI50 (see Table 1). Mean survival fraction (%) of treated cells as a percentage of the control population for HCT-116. Cells were seeded (400 per well) and allowed 24 h to attach before being challenged with jerantinine A (24 h). The number of colonies forming after 8 d incubation was determined. Mean (±S.E.M.) values are given. Data were generated from ≥3 separate trials; n = 2 per trial; (B) In vitro tubulin polymerisation in the presence of vehicle control, paclitaxel (5 μM; positive control), nocodazole (5 μM; negative control) or 1 (1 µM); (C) Immunofluorescent and DRAQ5 staining of x) untreated MCF-7 cells and y-z) cells exposed to synthetic 1 (1 × GI50 = 0.81 μM; 24 h), showing the effect on microtubules (green) and the cellular DNA (purple). Synthetic (−)-jerantinine A (1) caused multinucleation (i), nuclear fragmentation (ii) and formation of multipolar spindles (iii).
