Figure 6.

Knockdown of C1r and C1s suppresses growth of cutaneous squamous cell carcinoma (cSCC) in vivo. (a) cSCC cells (UT‐SCC‐91) were transfected with C1R small interfering (si)RNA_5 (n = 7), C1S siRNA_5 (n = 8) (120 nmol L⁻¹) or control siRNA (n = 8) and incubated for 72 h. Cells (7 × 10⁶) were injected subcutaneously into the back of severe combined immunodeficient mice and the size of tumours was measured twice a week (mean ± SEM). (b) Xenografts were harvested after 16 days and stained with haematoxylin and eosin (HE), and for immunohistochemistry for the proliferation marker Ki‐67, the vascular endothelial marker CD34 and the apoptotic marker active caspase‐3, with Mayer's haematoxylin as counterstain. Representative stainings from each group are shown. Arrows indicate CD34‐positive blood vessels. Scale bar = 100 μm. (c–e) The percentage of Ki‐67‐positive cells (c), the number of CD34‐positive blood vessels (d) and the percentage of active caspase‐3‐positive cells (e) were counted. *P < 0·05, **P < 0·01, ***P < 0·001 by Mann–Whitney U‐test.