Figure 1: Serpins inhibit pancreatic cancer cell growth but not breast cancer growth in NOD/SCID mice. NOD/SCID mice transplanted with Hs766t (n =27 total), MIA PaCa-2 (n =10 total) or MDA231 cells (n =16 total) were treated with saline, Serp-1, or neuroserpin for 2 weeks. Four weeks after transplantation, tumors excised from each group were weighed. (A) Growth of Hs766t xenografts was inhibited in mice receiving neuroserpin (n =6, P= 0.01) or Serp-1 (n =9, P= 0.03) treatment, when compared to saline (n =12). (B) Serp-1 treatment (n=5) also inhibited growth of another pancreatic cancer cell line, MIA PaCa-2 in NOD/SCID mice when compared to saline treatment (n =5, P ≤ 0.02). (C) Growth of the breast cancer cell isolate, MDA231 cells in NOD/SCID mice was not inhibited by neuroserpin (n=5, P= 0.76) or Serp-1 (n=6, P= 0.70). (D) In the time course study, NOD/SCID mice transplanted with Hs766t cells were treated each day with saline or Serp-1 throughout the 4 week experiment. Tumor suppressive effects of Serp-1 were evident after three weeks of treatment (P < 0.02). * indicates significance of P ≤ 0.05.