Figure 1: Animals with prostate cancer xenografts were randomized into control and treatment arms. Animals in treatment arm received 0.4% w/v Valproic Acid (VPA) in drinking water. Animals were treated for 35 days before excision of tumors. Tissue Microarrays (TMAs) of xenografts were created and expression of various markers was studied. Representative images of xenograft sections from control and VPA-treated groups; LNCaP, C4-2, and DU-145 (scanned at 20x magnification using the APERIO imaging system) are shown. (a) Immunohistochemistry (IHC) staining for acetylated histone 3. (b) Staining of cell cycle regulators (p21, p27, cyclin D1). (c) Staining for differentiation markers (Cytokeratin 18 (CK18), androgen receptor (AR)). (d) Staining for markers of proliferation (Ki-67), apoptosis (TUNEL), and angiogenesis (mean vascular density, MVD).