Fig. 2

Effects of NB and NB-acid on the inhibition of colony formation and apoptotic induction in NSCLC cells (H460, H292, H23, and A549) (A) NSCLC cells (H460 and H292) were seeded and treated with 0–25 µM of NB-acid and NB for 24 h. After that, they were further cultured for 7 days and stained with crystal violet for counting the colony number. (B) The cells were seeded and treated with 0–25 µM of NB and NB-acid for 24 h. Then, Hoechst 33,342 and PI were added to stain the cell nucleuses. Images were captured using a fluorescence microscope and the percentages of nuclear condensed and propidium iodide (PI)-positive cells were calculated. Data represent the mean ± SD (n = 3) (* 0.01 ≤ p < 0.05, ** p < 0.01, compared with the untreated control)