Figure 1. PCAIs inhibit lung cancer cell viability.

(A) Human lung cancer (A549, NCI-H1573, NCI-H661, NCI-H460, NCI-H1975, NCI-H1563, and NCI-H1299) and human lung fibroblasts (WI-38) cells were cultured and seeded in 96-well plates at a density of 2 × 10⁴ per well and allowed to attach overnight at 37°C in 5% CO₂/95% humidified air. Cells were then treated with either 1 – 50 μM of PCAIs (● NSL-BA-036, ○ NSL-BA-040, ▲ NSL-BA-055, ▼ NSL-BA-056) or (■) Paclitaxel, (□) Docetaxel and (◊) Erlotinib for 48 h as described in the methods. Cell viability was determined after the final treatment by fluorescence using the resazurin reduction assay. Each point represents the mean ± SEM relative to the control untreated cells. (B) To evaluate the importance of the polyisoprenyl moiety on cytotoxicity, A549 cells were assayed as described in (A) above, except cells were treated with NSL-100 and NSL-101. These compounds have a similar structure to the PCAIs but lack the polyisoprenyl moiety.