Figure 2.

Characterization of shikonin-associated cancer stemness activities by sphere-forming assay and mRNA expression of stemness genes on chemoresistant lung cancer cells. The stemness of lung cancer and sublines were evaluated by the number of spheroids calculated from the secondary sphere-forming assay (A) followed by shikonin treatment on A549/D16 cells (B) and A549/V16 cells (C) at the beginning of the second assay with indicated concentrations. The spheroids were harvested for measuring Nanog and Oct4 expression by qRT-PCR (D). * p ≤ 0.05 is considered statistically significant (red scale bar length of 500 μm).