Fig. 4

Zinc enhances tumorigenic potential of H460 lung cancer cells. a H460 cells were pre-treated with zinc (0–50 µM) for 24 h. The treated cells were subjected to 3D tumorigenesis assay. The cells were suspended in RPMI medium containing 4 % matrigel and zinc (0–50 µM) and plated onto agarose-coated plate. After 10 days, colonies were visualized under microscope; scale bar 500 µm. b Value was represented as average diameter and number of colonies in each field relatively to control cells using image analyzer. Values are means of independent triplicate experiments ± SD. *p < 0.05 versus untreated control