Liposome-based anchoring and core-encapsulation for combinatorial cancer therapy

Downregulated pro-apoptotic protein in cancer cells compromises the chemotherapy by a cytotoxic drug. Here, we report co-delivery of a pro-apoptotic protein, caspase 3 (Cas 3), and cytotoxic agent, oridonin (ORD), for synergistic cancer treatment, using a method of liposome-based anchoring and core encapsulation. First, ORD is modified with hyaluronic acid (HA) to improve its solubility. Then, the targeted co-delivery system is prepared by assembling the conjugate HA-ORD onto the Cas 3-loaded liposomes, which the surface HA can target the CD44 receptor on cancer cells. In vitro, the co-loaded liposomes (120 nm) are specifically taken up by 4T1 cells and endow a 1.5-fold increase of Cas 3. After intravenous injection into the tumor-bearing mice, the liposomes accumulate in the tumor with high efficacy and significantly inhibit tumor growth via promoting apoptosis and anti-proliferation of cancer cells. Mechanistically, the co-delivery works synergistically by upregulating the activated Cas form, cleaved-Cas 3.