Human lactoferrin inhibits growth of solid tumors and development of experimental metastases in mice
Bezault, J.; Bhimani, R.; Wiprovnick, J.; Furmanski, P.
Cancer Research 54(9): 2310-2312
1994
ISSN/ISBN: 0008-5472 PMID: 8162571 Document Number: 431935
The antitumor effects of the multifunctional iron-binding glycoprotein, lactoferrin (Lf), were investigated. Lf inhibited growth in mice of transplantable solid tumors induced by v-ras transformed fibroblasts and a methylcholanthrene-induced fibrosarcoma. Lf also substantially reduced lung colonization (experimental metastasis) by B16-F10 melanoma cells in syngeneic mice. Iron-saturated and apo-Lf exhibited comparable levels of tumor inhibition and antimetastatic activity. Transferrin, a related iron-binding protein, had no effect on lung colonization. In the B16-F10 system, elimination of natural killer cell activity by pretreatment of mice with anti-asialo G-M1 antibody abrogated the effects of Lf, whereas inhibition of macrophage function with silica did not. The results demonstrate a novel activity for Lf and suggest a potentially important role for this molecule in the primary defense against tumorigenesis.