Figure 4.

ABC transporter expression of the investigated SW480 cell clones. (A) Protein expression of ABC transporters was investigated in membrane-enriched fractions of the indicated cell lines by Western blotting. GADPH and β-actin were used as loading controls and A549 as positive control for ABCC1 and ABCG2 expression. Borders between cell lines indicate the rearrangement of original lanes of the same blot. (B) Immunofluorescence staining of ABCC1 (green) in SW480 and SW480/Coti cells. Cells were transferred to microscopy slides by cytospin and fixed with 4% PFA. DAPI (blue) and rhodamine-conjugated wheat-germ agglutinin (red) were used as counterstains for nuclei and membranes, respectively. (Scale bar: 50 μm).