Cellular senescence and oncogene induced senescence in particular is a potent tumour suppressor mechanism. Hepatocytes from subjects with chronic liver disease demonstrate evidence of senescence which may underpin declining liver function and place subjects at risk of HCC. We have utilised plasma membrane proteomics to develop a cell surface phenotype of senescence in order to identify signalling pathways that develop, reinforce and transmit the senescent phenotype to surrounding cells. We are developing tools to identify cellular senescence in vivo and are developing in vivo imaging modalities to image senescence in live subjects.