MDM2 and neoplasm: PDCD5 regulates the activities of TIP60 (Histone acetyl transferase), HDAC3 (Histone deacetylase 3), MDM2 (E3 ubiquitin-protein ligase–an antagonist of tumour suppressor activity of p53) and TP53 (Tumour suppressor protein 53) transcription factors [66].