ALCAM in Melanoma Motility and Adhesion Figure 1. Uveal melanoma cell lines display different speeds of migration that correlate with ALCAM expression. Time-lapse imaging of a wound created with a pipet tip in a layer of confluent cells (A) reveals the difference in wound closure in MUM-2B vs. MUM-2C. The speed of 5 uveal melanoma cell lines (minimum 3 trials each) is quantified (B). Both OCM-1A and MUM-2C move at less than 0.5 microns per minute; MUM-2B, C918, and M619 move at approximately 1.2 microns per minute. The speed of OCM-1A and MUM-2C are significantly different when compared to MUM-2B (t-test; 1A vs. 2B, p = 0.0008; 2C vs. 2B, p,0.0001). ALCAM protein expression as assayed by western blot shows that the cell lines fall into two groups – those with detectable ALCAM, and those without detectable protein expression (C). Tubulin is shown as a loading control. RT-PCR analysis of 4 of the 5 cell lines reveals that ALCAM mRNA expression mirrors protein expression (D). GAPDH is shown as a positive control. Percent gap closure was tracked for MUM-2B (E) and MUM-2C (F), and revealed that these two representative cell lines differ in their modes of migration. PLoS ONE | www.plosone.org 5 June 2012 | Volume 7 | Issue 6 | e39330