FIGURE 4.

Mmp1a and PAR1 are required for invasive stellate colony formation of lung cancer cells in three-dimensional matrices. A, growth and invasion of LLC1 cells transduced with control (shLuc), Mmp1a knockdown (shMmp1a-2), or PAR1 knockdown (shPar1) after 7 days in three-dimensional (3D) Matrigel cultures. Digital images were acquired at 60× magnification, n = 3). B, the grade of invasiveness was measured for each colony in three 6× fields and scored (grade 0, 1, 2) as described under “Experimental Procedures.”