Fig. 2

Cathepsin (CtsK) expression and distribution in MDA-MB-231 cells. a One representative Western blot of CtsK expression is shown from mock control and TRAP3^high cell lysate. Membranes were stained with anti-CtsK antibody and anti-β-Actin antibody. b Quantification of pro CtsK and mature CtsK (matCtsK) expression in mock control and TRAP3^high cell lysates from several Western blots with normalization to β-Actin (independent experiments n = 5, bar graphs represent means and Standard error) and statistically compared by ANOVA test (Fisher’s LSD test). c Immunocytochemistry (ICC) staining of total CtsK mock control and TRAP3^high cells (n = 3 independent cultures). Cells were stained with CtsK reactive rabbit antiserum (Alexa 488, green) and Hoechst (blue) and a representative maximum intensity projection is shown. d Coefficient of variation of Alexa 488 signal was calculated to analyze CtsK signal distribution over the cell. Means (8–20 cells in at least 3 fields of view) from 3 independent experiments were statistically compared by t-test