CD44 expression/secretion of cleaved form is higher in parental Karpas 299 cells than in Dep1 or 6RD3 cells. A. Whole cell lysates (30 μg) from cells grown on collagen I plates in the presence or absence of 10 ng/ml PMA for 24 hr. B. Concentrated conditioned media (75 μg) isolated from cells grown on collagen I plates for 24 hr. Samples were run on 7.5% SDS gels, transferred, and probed with anti-CD44H, followed by anti-mouse HRP. Of note is that intact CD44 migrates as a 100 kD protein, whereas the cleaved form migrates as a 70–75 kD species [36, 67]. Data are representative of three independent experiments.