In summary, our data show that the pharmacological effect of IPA‐3 is mediated, in part, by PAK‐1, demonstrate some of the first data suggesting that IPA‐3 is a potential therapeutic treatment for breast cancer and melanoma, and demonstrate the efficacy of liposome‐encapsulated IPA‐3 in breast cancer cells. The gene discussed is PAK1; the disease is breast carcinoma.