mRNA expression of apoptotic genes in A549 cells treated with ethanol extracts and water fractions from Prunella vulgaris var. lilacina . Cells were treated with the ethanol extract and water fraction of P. vulgaris var. lilacina at 10 μg/ml. Values are the mean ± SEM; different marks within treatments indicate significant differences (*p < 0.05, **p < 0.01, ***p < 0.001).