We confirmed that PPP2R2B-associated PP2A targets p70S6K and 4EBP1 for dephosphorylation, and thus reduced expression of PPP2R2B in breast cancer cells is associated with diminished p70S6K and 4EBP1 dephosphorylation by anti-HER2 treatment. The gene discussed is PPP2R2B; the disease is breast cancer.