In MDA-468 cells treated with exogenous TIMP-1 (100 ng/mL, Cat#: 970-TM, R&D systems), Akt phosphorylation (primarily at Ser473) increased within 5 min (Fig. 5f), suggesting that the Akt signaling pathway is involved in TIMP-1-induced breast cancer cell proliferation. Here, AKT1 is linked to breast cancer.