Mystique is highly expressed in MCF10A cells and is induced by IGF-I or ECM adhesion. (A) Cell lysates were prepared from MCF10A, MCF-7, and R+ and R– cells cultured in complete medium and assessed for Mystique 2 expression by using the anti-Mystique antiserum. Blots were reprobed with anti-RACK1 anti body as a loading control. (B) MCF10A or MCF-7 cells were starved from serum (24 h) before stimulation with IGF-I for the indicated times. Cell lysates were prepared for Western blotting with anti-Mystique antiserum or anti-β-actin as a loading control. (C) R+, MCF-7, or MCF10A cells were detached from tissues culture plates for 24 h before replating. At the indicated times, cell lysates were prepared for Western blotting with anti-Mystique antiserum and anti β-actin as a loading control.