MDM2 and tumour suppressor p53, illustration. Computer illustration showing MDM2 (mouse double minute 2 homolog, violet) bound to tumour protein p53 (blue), tagged with ubiquitin (yellow). p53 prevents cancer formation by acting as a tumour suppressor. It binds to the DNA (deoxyribonucleic acid) of cancerous cells and triggers self-destruction of that cell. MDM2 binds to p53, preventing it from binding to DNA and blocking its ability to destroy tumour cells. Several human tumour types have been shown to have increased levels of Mdm2. Therefore, MDM2 is being investigated as a potential target for cancer therapies.