Carbohydrate Mimetic Peptides as Anti-Cancer Therapeutics

Abstract

Carbohydrate mimetic peptides were screened for inhibition of selectin-mediated hematogenous metastasis of cancer cells. One peptide, designated I-peptide, showed an affinity for selectin in vitro and suppressed lung metastasis of melanoma cells in a mouse model. However, subsequent studies revealed that the in vivo receptor of I-peptide was not selectin but serine/arginine-rich alternative mRNA splicing factor and annexin A1 (Anxa1). Anxa1 is expressed on the surface of vascular endothelial cells in various malignant tumors, including brain tumors. IF7 peptide, an analog of I-peptide, showed specificity to the N-terminal region of Anxa1. IF7 rapidly accumulated in cancer cells by crossing the vascular endothelial cells. An IF7-anticancer drug conjugate suppressed tumor growth in mouse models of subcutaneous and brain tumors. These results indicate that IF7 functions as an efficient drug delivery system.