Fig. 4

Pathologically, EGFR and SAE2 were concurrently expressed in LADC patients with poor survival. a Using a Western blotting method, expression of EGFR was detected with various molecular weights in 18 tumor and eight non-tumor fractions of 20 pair of LADC biopsies. β-actin was used as a monitoring standard. b Using the same method, expression of SAE2 was detected as a 100-kDa protein in 19 tumor and two non-tumor fractions of LADC specimens. N non-tumor lung tissue (NTLT), T tumor fraction of surgical resections. c Representative examples of SAE2 expression in pathological specimens of LADC was determined by immunohistochemical staining (crimson precipitates). Expression of SAE2 was detected in the LADC tumor nests of (c1) papillary, (c2) acinar, (c3) solid, and (c4) mixed subtypes. (c5) In the NTLT, signal of SAE2 was detected in type II pneumocytes (the enlarged area), but not in type I pneumocytes of the air sac. d Comparison of Kaplan-Meier product limit estimates of survival analysis in LADC patients. (d1) Patients were divided into two groups depending on the expression of SAE2. The difference in survival between the two groups was compared by the log-rank test. Survival of patients with low SAE2 level was significantly better than those with high SAE2 level. The hazard ratio between these two groups was 1.708, and the difference in cumulative survival was significant (P = 0.002). (d2) Survival of stage I patients with low SAE2 level was significantly better as well. The hazard ratio was 4.08, and the difference in cumulative survival was significant (P = 0.0053)