Effects of Vacuolar H+-ATPase Inhibition on Activation of Cathepsin B and Cathepsin L Secreted from MDA-MB231 Breast Cancer Cells

Activity of cathepsins B and L in conditioned media and cell lysates following V-ATPase inhibition. Conditioned media (a) and cell lysates (b) from cells grown for 24 h in the absence (0 nM) or presence (100 nM) of concanamycin A were assayed for cathepsin activity. N = 5, error bars – std. dev, Student t test * p < 0.005, ** p < 0.0001. (c) Percent reduction in cathepsin activity following treatment with concanamycin A in conditioned media (CM) and cell lysates (Lysate). N = 5, error bars – std. dev., Student t test *** p < 0.0