Western Blot results validated the results from ELISA. Western Blot analysis with representative sera from lung cancer patients and NHC. Lanes 1–10 (research group), Lanes 11, 12 (validation group), sera from lung cancer patients; Lanes 13–16, sera from NHC. Lanes 4, 5, 7 and 9 show immunoreactivity with both MDM2 and c-Myc recombinant proteins; Lanes 6, 10 and 13 show strong reactivity with c-Myc recombinant protein, while they show weak reactivity with MDM2; Lanes 1, 8 and 12 show strong reactivity with MDM2 recombinant protein, while they show weak reactivity with c-Myc; Lanes 2, 3, 11, 14, 15 and 16 show no reactions with MDM2 or c-Myc. The last two lanes are negative control and positive control of MDM2 and c-Myc, respectively. Note: MDM2 and c-Myc proteins transferred to the NC membrane were purified his-tag proteins.