CDRI-85/287 inhibits EGF- EGFR interaction and antagonizes EGF- induced EGFR activation.

<p>(A) Effect on EGF-EGFR complex formation as determined by co-immunoprecipitation in MDA-MB 231 cells. Cells were incubated as shown in the figure for 48 h. Cell lysates were immunoprecipitated with anti-EGFR antibody and subsequently immunoblotted with anti-EGF. NC is the negative control. Left panel shows the representative blot showing EGF-EGFR complex and right panel shows the densitometric analysis of bands. The results are presented as mean± SEM of three independent experiments. p values are a-p<0.001, b-p<0.01, c-p<0.05 and d-p>0.05 vs. control. (B, C) Effect of CDRI-85/287 on EGFR activation was determined by ELISA. Cells were treated as indicated in the figure and analyzed for the expression of phosphorylated EGFR and total EGFR using ELISA kit as per manufacturer’s instructions. Activation of EGFR at different concentrations (left panel) and at various time points (right panel) in (B) MDA-MB 231 and (C) primary breast adenocarcinoma cells was determined by normalizing the expression of p-EGFR with EGFR. p values are a-p<0.001, b<0.01, c-p<0.05 and d-p>0.05 vs. control.