Table 2.

Haptotactic migration of functional variants of MDA-MB 435 breast cancer cells

	Lung	Parent	β3D723R	β3WT	β3−
VN	473  ± 32	225  ± 18	1125  ± 85	478  ± 42	198  ± 15
FN	372  ± 42	441  ± 42	1085  ± 95	1205  ± 110	275  ± 22
Fg	33  ± 12	15  ± 11	70  ± 12	18  ± 6	6  ± 4

Migration toward vitronectin (VN), fibronectin (FN), or fibrinogen (Fg) was analyzed for MDA-MB 435 parental cells (parent), an in vivo selected metastatic variant (Lung), or the β3-integrin lacking variant (β₃⁻) and its transfectants expressing either β3 wild-type (β3_WT) or constitutively activated β3_D723R. Cells were starved overnight in 0.5% FBS, and migration was assayed in transwell chambers (6 × 10⁴ per well in duplicate, 14 h). Migrated cells were counted at the filter underside in 10 random optical fields per filter by two observers. Columns represent mean numbers of migrated cells per field (± SD). Data comparing the metastatic cell variant (Lung) to the parental cells and data comparing β3-lacking cells to its β3 transfectants are from independent experiments. Absolute numbers of migrated cells varied between experiments, but the ratios of migratory activities between the cell types remained constant.