Low-dose heparin treatment does not inhibit SW480 human colon cancer growth and metastasis in vivo.

We investigated heparin effects on the biological behavior of SW480 human colon adenocarcinoma cells in vivo. Tumor growth, pathological features, metastatic potential and karyotype, were studied after the twelve week low-dose heparin treatment of nude mice subcutaneously injected with SW480 cells. A non statistically significant increase in tumor growth was observed (0.05 < p < 0.1, compared to the control group). No differences in tumor histology and karyotype were detected. Two of the six heparin-treated animals exhibited an increase in tumor vascularization. Metastasis to the lungs and liver was not inhibited. These results do not support the role of heparin in the prevention of the in vivo growth and metastasis of SW 480 colon cancer cells.