Increased cathepsin K in human cervical cancer specimens. A) Tumor tissues from stages I-III cervical cancer and normal tissues were obtained and prepared as described. 10 μg of protein were loaded for multiplex cathepsin zymography, and a representative zymogram with protein ladder (lad), cathepsin K, L and S positive controls is shown and cropped for clarity. B) Cathepsins K, L, and S activities were quantified by band densitometry and represented by the box and whisker plot shown to exhibit patient to patient variability. For box and whisker plots, the top and bottom of the box represent the 75th and 25th quartile, and whiskers +1.5 SD and -1.5 SD, respectively (n = 4-7, #p < 0.05 compared to normal). C) Patient-matched comparisons of normal to tumor cervical tissue cathepsin K activity yielded an increase of ~12 fold (n = 5, *p < 0.05).