Karen's research focuses on the tumour suppressor protein p53, which plays an important role in cancer prevention. Her lab is interested in understanding the signals that induce p53 and the functions of p53 that contribute to its ability to prevent cancer progression. This work has also expanded to encompass an interest in cancer metabolism. Ultimately, the hope is to be able find ways to translate this research for cancer therapy.

Karen has been elected as a Fellow of the Royal Society, the Royal Society of Edinburgh, the Academy of Medical Sciences, EMBO, the European Academy of Sciences, the American Academy of Arts and Sciences, the American Association of Cancer Research Academy and the National Academy of Sciences.