Fig. 3
a Gelatine zymography of total protein lysates from osteosarcoma pretreatment biopsies. Latent pro- and active forms of MMP2 and MMP9 were detected and are marked by arrows. Response to preoperative chemotherapy according to the six-grade scale of Salzer-Kuntschik is indicated. (P = positive control, N = negative control) (b) Densitometric quantification of pro- and active forms as well as the total amount of MMP2 and MMP9 in the good and poor responder group. The lower boundary of the box indicates the 25th percentile, and the upper boundary the 75th percentile. The whiskers indicate the highest and lowest values. Medians are indicated. P-values were determined by Mann-Whitney U-test (**p < 0.01, *p < 0.05). c Ratios of the active forms, the latent pro-forms and total MMP2/MMP9 in osteosarcoma biopsy samples from good and poor responders. P-values were determined by Mann-Whitney U-test (**p < 0.01, *p < 0.05)