KRAS and non-small cell lung carcinoma: To determine the effect of berberine and coptisine on the KRAS transcription levels, a quantitative reverse transcription PCR (qRT-PCR) experiment was performed on non-small cell lung cancer cells (H460 and A549) which harbor KRAS mutations with unfavorable therapeutic outcomes, and normal human bronchial epithelial cells (BEAS-2B)3,64.