Figure 1

TACE and TIMP3 mRNA expression were detected by RNA in situ hybridisation (A–I, hybridisation signals: blue). (A) Moderate TACE mRNA expression in dysplastic epithelium and (C) strong TACE hybridisation signals in HNSCC. (E) No TACE mRNA expression in normal epithelium. Control riboprobes in sense orientation against TACE ((B) control to (A), (D) control to (C), and TIMP3 (H) to (G)) yielded no signals. Moderate to strong TIMP3 mRNA-specific signals are found in dysplastic epithelium (F), in HNSCC (G) and stromal areas adjacent to HNSCC (I). EGFR protein detected by immunohistochemistry (J–L). EGFR protein is highly expressed in basal and parabasal cells of normal epithelium (J), dysplastic (K) and HNSCC (L) epithelia. Slides were counterstained with nuclear fast red dye (in situ hybridisation, pink) and haematoxylin (immunohistochemistry, blue); original magnification: × 200.