FIGURE 2: Dose dependent inhibition of colony formation in AuNPs treated pancreatic cancer cell lines. Three pancreatic cancer cell lines, PANC-1 (a), AsPC-1 (b) and MIA-PaCa-2 (c), were first seeded with the complete medium (200 cells/well) and 24 h after seeding, treated with different concentrations of AuNPs (5 μg/ml, 10 μg/ml or 25 μg/ml). 7-10 days later, the colonies were stained with crystal violet and the numbers of colonies were counted (Gelcounter). (a-c) The colonies formed with different pancreatic cancer cells with different concentration of AuNPs treated. (d-f) Relative colony numbers corresponding to a-c. Independent experiments were repeated for at least three times and each time, at least triplicate wells were used. Values are means ± SD and statistical analysis were done using one-way ANOVA. *P≤0.05, **P≤0.01.