Glucose is the main source of fuel that cancer cells use to divide and reproduce uncontrollably. For some time, this had led scientists to believe that most of the cell mass in new cancer cells comes from glucose. Now new findings from a group including KI members Eisen and Chang Career Development Professor Matt Vander Heiden and Andrew and Erna Viterbi Professor Scott Manalis, suggest that the largest source for new cell material is amino acids, which growing cells consume in considerably smaller quantities than glucose. The paper, published in Developmental Cell, offers a new way to look at cancer metabolism, a process that Vander Heiden mentioned in a recent NPR interview plays an important role in cancer development.