Figure 1.
Characteristics of the mouse melanoma model. (A) Cell viability was determined by the MTT assay in triplicate. (B) Tumorigenicity assay in vivo. Mice were subcutaneously injected with 2 x 105 cells. Bars: SD of the mean of five animals per group. ***P < .0001. (C) Survival curves (100% x number of mice alive after each day / total number of mice at day 0) for mice inoculated with 4C3- and 4C3+. Experimental metastasis assay: 2 x 105 4C3+ cells (D) and 4C3- (E, F, and G) were injected through the caudal vein. Mice were killed 20 (D and E), 40 (F), and 80 (G) days later; their lungs were removed; and metastatic foci in the lungs were identified and some are indicated in panel D by the white arrows. ma indicates melan-a cells; 2C and 4C, melan-a cells submitted to two and four substrate adhesion blockade cycles, respectively; 4C3-, slow-growing melanoma cell line; 4C3+, fast-growing melanoma cell line.