Cancer
metastasis that is resistant to conventional therapies has
become a major cause of patient death. Recent reports indicate that
the neutrophil extracellular trap (NET) is closely associated with
cancer distant metastases, and the cell-free DNA of NETs has been
identified as the ligand of the transmembrane protein CCDC25 of cancer
cells, acting as a chemokine to induce cancer cell migration to distant
organs. In this work, we present the poly(aspartic acid) based-cationic
materials to interfere with the interaction between NET-DNA and CCDC25,
and furthermore to inhibit NET-DNA-mediated cancer cell chemotaxis
and migration. Because of a stronger binding affinity to DNA and favorable
retention in the liver, nanoparticulate poly(aspartic acid) derivatives
(cANP) efficiently reduce the level of hepatic NET-DNA infiltration,
leading to a significant suppression of cancer metastases in mice
and several human metastatic models. Moreover, the cANP exhibits no
toxicity to organs of animals during the entire treatment. Thus, this
work suggests a strategy for controlling cancer metastases, which
will benefit patients in clinics