To determine whether these genes are regulated by MYC and the NuA4 complex in human cancer cells, MYC and Tip60 (the core HAT enzyme in the NuA4 complex) were knocked down in MB231 human breast cancer cells by using two independent shRNA clones targeting different genomic regions of MYC or Tip60 (see Materials and Methods). Here, KAT5 is linked to breast cancer.