Mesenchymal stem cells (MSCs), due to their
tumor tropism, are strongly recruited by various solid
tumors and mobilized by inflammatory signals in the tumor microenvironment. However, effective cellular uptake is critical for MSC-based
drug delivery. In this study, we synthesized a spherical copolymer,
polyethylenimine-poly(ε-
caprolactone), with aggregation-induced emission (AIE) material and the anticancer
drug,
paclitaxel, coloaded onto its inner core. This was followed by the addition of a
transactivator of transcription (TAT)
peptide, a type of
cell-penetrating peptide, to modify the nanoparticles (NPs). Finally, the MSCs were employed to carry the TAT-modified AIE-NPs
drug to the
tumor sites and assist in simultaneous
cancer diagnosis and targeted
tumor therapy. In vitro, the TAT-modified AIE-NPs showed good biocompatibility, targeting, and stability in an aqueous
solution besides high
drug-loading and encapsulation efficiency. In vitro, the AIE-NPs exhibited a controllable release under a mildly acidic environment. The in vivo and in vitro studies showed high antitumor efficacy and low cytotoxicity of the AIE-NP
drug, whereas biodistribution confirmed the
tumor tropism of MSCs. To summarize, the MSC-based AIE-NP drugs loaded with TAT possessed good biocompatibility and high antitumor efficacy via the enhanced NP-
drug uptake. In addition, the
tumor tropism of MSCs provided selective
drug uptake by the
tumor cells and thus reduced the systemic side effects.