Macrophage colony stimulating factor inhibits experimental liver metastases from colon cancer

This study investigated the inhibitory effect of human macrophage colony stimulating factor (hM-CSF) on experimental liver metastases. Murine colon cancer cell lines C-26 and C-36 were each injected into the spleen of BALB/c mice and the number of subsequent liver metastases was counted. An optimal dose (3,000U/body/day) of hM-CSF to inhibit liver metastases was identified. Additionally, hM-CSF (3,000U/body/day) administration for 7 days before and after the injection of the same cancer cell lines was investigated. The mean number of liver metastases decreased significantly in the hM-CSF group compared with the saline group. These results suggest potential therapeutic benefit for the use of hM-CSF in the adjuvant treatment of liver metastases.