Chemotherapy using curcumin (Cur) and 5-fluorouracil
(5-FU) has
been broadly applied to treat colorectal cancer (CRC). In situ chemotherapy
mediated by biological macromolecule platforms, such as gelatin-based
injectable hydrogels, has recently attracted sizable attention due
to their injectability, biocompatibility, and high therapeutic efficacy.
Here, a microgel-embedded and micelle-cross-linked injectable hydrogel
composite (MMHC) was synthesized for combinational local delivery
of 5-FU and curcumin. The hydrophobic core of Pluronic-based micelles
in injectable hydrogel was prepared for loading curcumin as a hydrophobic
drug. The microgels were physically entrapped into the injectable
hydrogel for sustained hydrophilic drug delivery. 5-FU release could
be sustained for more than a month from these composite hydrogels,
which is considerably longer than that achievable using the microgels
alone. The proliferation inhibitory effect and cell cycle arrest were
observed in HT-29 cells using the dual drug loaded MMHC system. In
conclusion, the Cur/5-FU@MMHC system is a synergistic therapeutic
delivery system that can achieve prolonged, sustained-release action
for the combination of 5-FU and curcumin against the human colon cancer
cell line HT-29.