Coagulation proteases activate the secretory pathway in the 4T1 cell line. (A) 4T1 cells were treated for the indicated amount of time with SFM, FXa, thrombin, or 200nM PMA. Blots were probed with antibodies for p-PKCμ and GAPDH. Data shown is representative of 3 independent experiments. (B) 4T1^GFP, 4T1^ΔPAR-1, and 4T1^ΔPAR-2 cells were treated with SFM, FXa, thrombin, or PMA for 5 minutes. Blots were probed with antibodies for p-PKCμ and GAPDH. Phosphorylated PKCμ was quantified by dividing the background-corrected p-PKCμ signal intensity by the background corrected GAPDH signal intensity. The blot shown is representative of at least 3 independent experiments. Quantification results are shown as mean ± SEM of at least 3 independent experiments. *P ≤ .05 (4T1^GFP versus 4T1^ΔPAR-1) and ^#P ≤ .05 (4T1^ΔPAR-1 versus 4T1^ΔPAR-2).