Fig. 1

Protein ectodomain shedding during p95HER2-induced senescence. a Left, MCF7 Tet-Off p95HER2 cells were treated with or without doxycycline as indicated in two independent experiments (#1 and #2). The extracellular media were analyzed by label-free quantitative proteomics in triplicate (A-C) (Additional file 1: Figure. S1). The heatmap shows log₂FC of the normalized levels of soluble ectodomains. Right, transcriptomic analysis of the same cells treated as in left panel (a). b MCF7 Tet-Off p95HER2 cells were treated with or without doxycycline for 7 days. Conditioned media from the last two days and cell lysates were analyzed by Western blotting as indicated. c Quantitative results from at least three independent experiments performed as in (b) were expressed as average ± standard deviation. Note that the levels of Areg were determined by enzyme-linked immunosorbent assay. d log₂FC of the ectodomain levels and the log₂FC of their corresponding transcripts levels, determined as described in (a), are represented. Linear regression line is shown (R² = 0.528); P <0.001 using the Spearman correlation coefficient. APP amyloid precursor protein, Areg amphiregulin, EpCAM epithelial cell adhesion molecule, Ephrin type-B receptor 4, DDR1 discoidin domain receptor family, member 1, GAPDH glyceraldehyde 3-phosphate dehydrogenase