Time-lapse analysis of HT1080 invasion: LPA and S1P induce ~700 μm of invasion of 3D collagen matrices. (A) HT1080 cells were seeded onto 3.75 mg/ml collagen gels in glass casings (see methods for details) and allowed to invade for 48 hours in the presence of DMEM, LPA, S1P, LPA and S1P (1 μM each) or LPA (1 μM) + GM6001 (5 μM). Digital images of representative fields were captured at ten minute intervals. Using Metamorph®, invasion distance measurements at each time point from triplicate wells were obtained (n = 15). Magnification = 10×. Scale bars = 200 μm. (B) Data from panel A were plotted versus time and rates of invasion were calculated using linear regression (see Table 1). Data are expressed as mean invasion distance (n = 3 wells, ± S.D.) for each time point from triplicate experiments.