Reuben Harris, PhD of University of Minnesota, Minneapolis, MN talks about APOBEC-3B as a candidate biomarker for response to therapy. Tumors expressing higher levels of APOBEC-3B and APOBEC-3H are more likely to have a higher overall mutation rate and evolvability. Dr Harris points out that targeted therapies could become undermined by resistance mutations, especially in a tumor that is mutating at a high rate. Recorded at the 2016 National Cancer Research Institute (NCRI) Conference in Liverpool, UK.