MUC1.CT directly interacts with transcriptional repressor ZEB1.

<p>A) Co-immunoprecipitation (Co-IP) was utilized to evaluate the interaction of the MUC1.CT and ZEB1 in S2.013.Neo and S2.013.MUC1 cells. Cell lysates were immunoprecipitated with an antibody against the MUC1.CT, and the subsequent western was blotted with an antibody to ZEB1. Non-immunoprecipitated lysates were used as a loading control, and steady state levels of ZEB1 were higher in S2.013.MUC1 cells compared to S2.013.Neo cells. B-C) Proximity ligation assay (PLA) was used to visualize MUC1.CT and ZEB1 interaction in S2.013.Neo and S2.013.MUC1 cells, B, and Panc1.Neo and Panc1.MUC1 cells, C (with representative compressed z-stack image for each). These data show quantitative levels of MUC1.CT and ZEB1 interactions, indicating that MUC1.CT and ZEB1 interact in both cell lines. In the S2.013.Neo and S2.013.MUC1 cell lines, the interaction was significantly higher in the MUC1 expressing cells, confirming the Co-IP in A. However, there was no significant difference in interaction in the Panc1.Neo and Panc1.MUC1 cells. (Student’s t-test: *** p < 0.0005).