Correlation between HDAC1 and HDAC2 in NSCLC tissue . Both HDAC1 and HDAC2 expression is localized to the nucleus. Case 1 (A, B), squamous cell carcinoma, T1N0M0. Case 2 (C, D), squamous cell carcinoma, T2N0M0. Case 3 (E, F), adenocarcinoma, T3N1M0. Case 4 (G, H), adenocarcinoma, T1N0M0. Immunohistochemical streptavidin–peroxidase method, magnification × 200.