Detection of the distribution of HA in shHAS3 knockdown xenografts by double staining for tumour cells (CK18) and HA. Section from the same series as in Figure 3 were double stained for HA (red) and CK18 (green) to determine the exact location of HA in the xenograft tumour sections. (A) Scrambled control sections revealed a strong HA signal in tumour and stroma. (B) HA staining in shHAS3 samples showed a strong signal in the stroma and tumour/stroma interface (arrows). However, HA was much less pronounced within the tumour cell clusters. Scale bars, 30 μm. Shown are representative images of n = 6 (control) and n = 7 (shHAS3) experiments.