Figure 6. Association of the expression of Nrf2, MKP-1, and HO-1 in human lung adenoma tissues. Images of immunochemical staining for MKP-1 (A–C), Nrf2 (D–F), and HO-1 (G–I) from three representative lung adenoma tissues. Case 1, well-differentiated adenoma with weak positive staining for MKP-1 (A), Nrf2 (D), and HO-1 (G). Case 2, moderately-differentiated adenoma with moderate positive staining for MKP-1 (B), Nrf2 (E), and HO-1 (H). Case 3, poorly-differentiated adenoma with strong positive staining for MKP-1 (C), Nrf2 (F), and HO-1 (I). Original magnification ×400; scale bar, 50 μm.