Supporting Information Text S1 (DLS). (DOC) Detail description of Dynamic Light Scattering Figure S1 Immunoblotting analysis of EGFR, Src, Stat3, and RHA from Panc-1, MDA-MB-231, or A549 cells. Immunoblotting analysis of (A and B) fractions collected from gel filtration chromatographic analysis of Panc-1 cell lysates probing for EGFR, Src, Stat3,or RHA (A), or EGFR immunecomplex from the pooled fractions 23–27 probing for Stat3, Src or EGFR (B), or (C) immunecomplexes of EGFR or Stat3 from nuclear extracts of human breast cancer, MDA-MB-231 or non-small cell lung cancer, A549 cells probing for EGFR, Stat3 and Src. Bands corresponding to proteins in gel are shown; Data are representative of 2 independent studies. (TIF) Figure S2 The principle of DANS technology (Detection and Analysis through Nanoparticle Sizing) for protein complex detection and binding partner analysis. (TIF) References 1. Ulrich A, Schlessinger J (1990) Signal transduction by receptors with tyrosine kinase activity. 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