Rapidly growing
cancer cells exhibit a strong dependence on
iron for their survival. Thus,
iron-removing drugs,
iron chelators, have potential applications in
cancer treatment.
Deferoxamine (DFO) is an efficient
iron chelator, but its short circulation half-life and ability to induce
hypoxia-inducible factor 1α (HIF1α) overexpression restricts its use as an
antitumor agent. In the present study, we first found that a pattern of
iron-related
protein expression favoring higher intracellular
iron closely correlates with shorter overall and relapse-free survival in
pancreatic cancer patients. We subsequently found that a combination of DFO and the HIF1α inhibitor, lificiguat (also named YC1), significantly enhanced the antitumor efficacy of DFO in vitro. We then employed
transferrin receptor 1 (TFR1) targeting
liposomes to codeliver DFO and YC1 to pancreatic
tumors in a mouse model. The encapsulation of DFO prolonged its circulation time, improved its accumulation in
tumor tissues via the enhanced permeability and retention (EPR) effect, and facilitated efficient uptake by
cancer cells, which express high level of TFR1. After entering the
tumor cells, the encapsulated DFO and YC1 were released to elicit a synergistic antitumor effect in subcutaneous and orthotopic
pancreatic cancer xenografts. In summary, our work overcame two major obstacles in DFO-based
cancer treatment through a simple
liposome-based drug delivery system. This nanoencapsulation and targeting paradigm lays the foundation for future application of
iron chelation in
cancer therapy.