Figure 7.

Immunohistologic detection of Lamγ2 overexpression in vivo and its association with increased p-S6 and p-eIF4B levels in basal cells of oral premalignant dysplasias. In normal human oral mucosal epithelium (A), oral mucosal dysplasias (B–D), and a microinvasive oral SCC arising from a dysplasia (E), sections were stained with H&E and immunostained for Lamγ2 and p-S6. Enlargements of the areas demarcated by small rectangles are shown as corresponding insets, with the basal lamina traced by dotted lines. Scale bar = 200 μm. A: Normal oral epithelium showing no Lamγ2 and only suprabasal p-S6 staining. B: Margin between normal epithelium (left half) and dysplasia (right half), showing no Lamγ2 and p-S6 confined to suprabasal cells in the normal region, contrasting with Lamγ2 and basal cell p-S6 in the dysplastic region. C: Dysplasia in which not all basal cells are p-S6⁺, not all p-S6⁺ cells overexpress Lamγ2, and the intensity of Lamγ2 immunostaining varies greatly. D: Region of a dysplasia in which many basal cells are p-S6⁺, but none express Lamγ2. E: Dysplasia overlying microinvasive SCC (indicated by arrowheads in the H&E-stained panel), showing variable Lamγ2 and basal p-S6 staining in the dysplasia and strong Lamγ2 and basal p-S6 staining in areas of microinvasive SCC.