Total RNA from 8 cell lines, blood samples, 75 cancer tissues of NSCLC and the adjacent normal tissues were extracted in TRIZOL RNA extraction reagent (Invitrogen) by manual. The experiment was performed as follows: the tissues were added with 500 ul Trizol and 200 ul chloroform in order, after vibrating and standing, then were placed into centrifugal machine for 10 min, mixing with isopropanol and ethanol to discard supernatant by centrifugation; following that, the tissues were added with 20-50 ul DEPC-ddH2O to dissolving dissolve RNA using 20-50ul DEPC-ddH2O and preserved saving with absolute ethanol in refrigerator at −70°C.