PAK1 and breast cancer: PAK‐1 has also been suggested to be involved in the early stages of breast cancer and may partially participate in the mechanisms mediating the transformation of mammary epithelial cells into mesenchymal malignant cells.12 Studies have also shown that overexpressed or hyperactivated PAK‐1 mediates the anchorage independence of transformed epithelial cells during the progression of breast cancer.12, 13 PAK‐1 is also essential for AKT‐ and Ras‐induced oncogenic transformations in both prostate and breast cancer cells.14, 15