Fig. 4.

Reciprocal activation of receptor tyrosine kinases induced by the crosstalk. a Distribution of phosphorylation ratio of pY peptides. Blue dots: log 2 transformed ratio of MDA-MB-231-co-cultured versus MDA-MB-231; Red dots: log 2 transformed ratio of 82T-co-cultured versus 82T. b, c Representative spectrum of FGFR1 (b) and EGFR (c) identified in cancer epithelium and CAFs. Top panels: MS spectra and bottom panels: MS/MS spectra for phosphotyrosine-containing peptides identified for FGFR1 and EGFR