When the KRas-CSK biosensors were transfected in human normal BEAS-2B lung epithelial cells and human A549 non-small cell lung cancer cells (Figure 6D), we found that the ECFP/FRET ratio in these two cell types was within 0.35~0.5 (Figure 6E). The gene discussed is CSK; the disease is non-small cell lung carcinoma.