Effect of MβCD treatment on MUC1 and MAL2 distribution in lipid raft fractions. SK-BR-3 and MDA-MB-435(M) cells were treated (+Mβ), or not (-Mβ), with 20 mM MβCD, extracted with 1% Triton X-100 at 4°C, and subjected to sucrose gradient centrifugation. Twelve fractions of 1 ml (Fr, as shown above each top panel) were collected and 15 μl aliquots were subjected to SDS-PAGE and Western blot analysis with antibodies to MUC1, MAL2 or CAV1, as indicated at the left, with sizes of detected proteins indicated at the right. In all panels, vertical lines between fractions 8 and 9 distinguish samples loaded on different gels. In fractions 2–4, MUC1, MAL2 and CAV1 were not detected in SK-BR-3 cells, or were significantly reduced in MDA-MB-435 [M] cells following MβCD treatment. Results shown represent those obtained from 3 independent experiments.