Confocal microscopic immunofluorescent images of the microtubule structure within ESE-16-exposed HeLa cells. Alexa-488 fluorescent labeled tubulin-α antibodies fluoresce green allowing visualization of the tubulin network, while DAPI stained nuclear material blue. (ai) DMSO exposure (vehicle control) demonstrated cell confluency, various stages of cell division and intact organised tubulin networks as seen in medium only exposed cells (not shown). (aii) A cell in telophase, demonstrating intact microskeletal structure. (bi) and (bii) HeLa cells exposed to 2-ME as a positive control for a microtubule depolymerizing agent, demonstrated compromised cell density and cells in metaphase block with disorganised tubulin structures. (ci) and (cii) 24 Hour ESE-16 exposure showed complete tubulin disintegration together with apoptotic body formation, DNA margination and a decrease in cell density. (Arrow colour key: orange = nucleoli; yellow = DNA margination; white = apoptotic bodies; red = microtubules, organized and intact in the DMSO vehicle control, and disintegration in the 2-ME control and ESE-16-treated cells).