Immunoblotting assays for Muc-1 expression in human MM and prostate cancer cell lines stimulated with Dex. Cell lysates obtained from human MM (S6B45 and RPMI 8226) and prostate cancer (DU145) cells cultured with media alone or with Dex (10⁻⁸mol/L) for 24 hours were examined by Western blot analysis using the VU-4H5 MoAb. Dual bands seen in the lysates from S6B45 and DU145 cells show coallelic expression of Muc-1.1 The DMA1 MoAb to -tubulin was used as a control antibody.