Efficacy of liposomal curcumin in a human pancreatic tumor xenograft model: inhibition of tumor growth and angiogenesis.

ABSTRACT

BACKGROUND: Liposome-based drug delivery has been successful in the past decade, with some formulations being Food and Drug Administration (FDA)-approved and others in clinical trials around the world. The major disadvantage associated with curcumin, a potent anticancer agent, is its poor aqueous solubility and hence low systemic bioavailability. However, curcumin can be encapsulated into liposomes to improve systemic bioavailability. MATERIALS AND METHODS: We determined the antitumor effects of a liposomal curcumin formulation against human MiaPaCa pancreatic cancer cells both in vitro and in xenograft studies. Histological sections were isolated from murine xenografts and immunohistochemistry was performed. RESULTS: The in vitro (IC50) liposomal curcumin proliferation-inhibiting concentration was 17.5 µM. In xenograft tumors in nude mice, liposomal curcumin at 20 mg/kg i.p. three-times a week for four weeks induced 42% suppression of tumor growth compared to untreated controls. A potent antiangiogenic effect characterized by a reduced number of blood vessels and reduced expression of vascular endothelial growth factor and annexin A2 proteins, as determined by immunohistochemistry was observed in treated tumors. CONCLUSION: These data clearly establish the efficacy of liposomal curcumin in reducing human pancreatic cancer growth in the examined model. The therapeutic curcumin-based effects, with no limiting side-effects, suggest that liposomal curcumin may be beneficial in patients with pancreatic cancer.