AR and breast cancer: For example, ZIF-8 modified with the novelMCF-7 breast cancer targeting peptides (AR peptide) was used for simultaneousencapsulation of DOX and indocyanine green (ICG) with high encapsulationefficiency.24 Such a composite providesa dual targeting mechanism as the AR peptide is bound to it and ZIF-8dissolves under acidic tumor conditions, allowing controlled releaseof ICG and DOX.