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The importance of hemostasis in tumor development is increasingly being recognized. Many tumor cells express procoagulant activity consistent with a putative role for coagulation in tumor cell migration, invasion, and metastasis. To explore and observe the affects of coagulation components, particularly fibrin(ogen), on tumor growth and invasion we utilized the chicken chorioallantoic membrane (CAM) model for the propagation of cancer cell lines grown in human plasma and fibrinogen clots. Cell lines of human breast cancer MCF-7, MDAMB231; ovarian cancer 2008, SKOV3; and prostate cancer PC3 were placed onto 9d CAMs (1x106 cells) in culture medium (CM), human fibrinogen clot (HFC), or human plasma clot (HPC) and incubated until 11d or 14d. CAMs were fixed in formalin; paraffin embedded and cross sections were prepared. Alterations in the CAM were monitored at 24-hour intervals with light microscopy and digital imaging. Cancer cell invasion into the CAM, angiogenesis, inflammation, and epithelial proliferation were evaluated and quantified on a + to 4+ basis from hematoxylin, eosin stained and immunohistochemically treated sections. Cancer cell colonies formed on all of the CAMs by 24h. In section at 48h cancer cells were observed within the parenchyma of the CAM, associated with damage to or removal of the epithelial layer. Cancer cell invasion increased when cells were grown in HPC (3+) compared to HFC (2+) and cells cultured in HFC displayed a higher level of invasion than CM (+/−) cells. There was limited evidence of angiogenesis, and this was similar among the growth conditions, but epithelial proliferation and inflammation demonstrated a similar trend to invasiveness. Breast cancer cell lines grown in HPC showed the greatest increase in invasive potential (3+), and as well were associated with the most enhanced angiogenesis, epithelial proliferation and inflammation compared to other growth conditions. Ovarian cancer cells displayed an intermediate response to culture in HPC (2+), and prostate cancer cells were the least responsive (+). A correlation between cancer cell invasiveness in the presence of HPC and to a lesser extent in HFC suggests a significant relationship among coagulation factors and metastasis. The increased potential of plasma clot compared to fibrinogen clot is consistent with the involvement of other coagulation components in tumor growth and metastasis. It is possible that a clot environment induces a more aggressive phenotype stimulating the production of matrix metalloproteinases and growth factors. The elucidation of the interplay of other coagulation factors, thrombin or tissue factor, and the distinct mechanisms of the interactions with tumor invasion and metastasis may impact cancer treatment.

[Proc Amer Assoc Cancer Res, Volume 45, 2004]