Squalene

To determine if metabolic intermediates of the mevalonate pathway or LDL treatment revert the cells’ atorvastatin-sensitive phenotype, the statin-sensitive cancer cell line HOP-92 was seeded in 12-well plates at a density of 1 × 10⁵ cells/mL (1 mL/well), incubated overnight, and then treated with 10 μM atorvastatin and various concentrations of R-mevalonic acid (10–50 μM; Sigma-Aldrich, St. Louis, MO), ubiquinone (25–200 μM; Wako, Osaka, Japan), dolichol (75–300 μM; Avanti Polar Lipids, Alabaster, AL), squalene (10–100 μM; Wako), FPP (1–25 μM; Echelon, Salt Lake City, UT), GGPP (1–25 μM; Sigma-Aldrich), or LDL (50–200 μg/mL; Alfa Aesar, Ward Hill, MA) for 48 hours. We chose the doses of each substrate according to published references [53 (link), 54 (link)]. In select experiments, we photographed these cells with a phase-contrast microscope to capture any morphological changes. After the incubation, cells were harvested, and cell numbers were counted using a Scepter handheld automated cell counter (Millipore). Statistical analyses were performed using one-way ANOVA and Bonferroni-Dunn post-hoc tests. P values of less than 0.05 were considered statistically significant.