Additional file 1: Figure S1. Supporting data to Fig. 1. A. Example dot plots for apoptosis assay in Fig. 1C. B. Densitometric analysis of phospho-SMAD1/5 relative to GAPDH levels in Fig. 1D. C. Densitometric analysis of phospho-SMAD2/3 relative to GAPDH levels in Fig. 1D.