Figure 2.

Exposure of6-aminonicotinamide (6-AN) suppresses the proliferation of lung cancer cells. (A) Representative images of colony-forming assays in A549 (upper panel) and H460 (lower panel) stained with crystal violet after indicated doses of 6-AN treatment for 48 h. Graphs indicate the number of colonies formed after each treatment condition in both cell lines. (B) Cellular expression of the Ki-67 proliferation marker in A549 and H460 lung cancer cells after 48 h of 6-AN treatment at low (10 μM) and high (200 μM) doses. Cells were labeled by immunofluorescence for Ki-67 (red) with 4,6-diamidino-2-phenylindole (DAPI; blue) as the nuclear counterstain. * p < 0.05; ** p < 0.01; *** p < 0.001.