Figure 4

Expression status of MUC1, surfactant apoprotein A, MUC4, ERbB2, p27, CEA, MUC5AC and p16 in micropapillary pattern and non-micropapillary pattern areas in cases of primary small-size lung adenocarcinoma. The matrix shows the correlation of expression of each protein in the micropapillary pattern and non-micropapillary pattern areas in carcinoma tissue, based on immunohistochemical staining. The expression level was determined by the percentage of tumor cells that stained positively. MUC4 expression in micropapillary pattern areas was lower than in non-micropapillary pattern areas (Fisher's exact probability test, P<0.05). All other proteins showed no significant difference in expression between micropapillary pattern and non-micropapillary pattern areas. MUC1 showed strong expression in both areas.