Abstract: One aspect according to the present disclosure relates to a novel nucleic acid ligand which is a new class of nucleic acid compound, the existence of which was considered impossible in the prior art. The novel nucleic acid ligand has specific binding affinity with respect to at least two different targets having three-dimensional structures, and the binding sites for the at least two targets are formed in or from a single nucleic acid ligand. The novel nucleic acid ligand according the present disclosure can simultaneously solve several problems of existing aptamers that the prior art could not solve. One aspect according to the present disclosure relates to a novel screening method for identifying the above-mentioned novel nucleic acid ligand. The novel screening method uses a step for sequentially contacting at least two different targets having three-dimensional structures to screen a novel nucleic acid ligand that was previously thought impossible.

Abstract: A composition for imaging a tumorous disease region includes a fluorescence- or radioactive isotope-labeled ERBB2 aptamer, wherein the ERBB2 aptamer labeled with a radioactive isotope or a fluorescent dye is used to image the tumorous disease region in vivo. The composition may include a labeled hybridized aptamer comprising an aptamer represented as formula 1 hybridized with a labeled-ODN represented as formula 2.

Abstract: A cancer targeted therapeutic agent includes a drug-linker-AS1411 structure. The drug may be selected from monomethyl auristatin E (MMAE), monomethyl auristatin F (MMAF), cytarabine, gemcitabine, maytansine, DM1, DM4, calicheamicin and a derivative thereof, doxorubicin, duocarmycin and a derivative thereof, pyrrolobenzodiazepine (PBD), SN-38, a-amanitin, or a tubulysin analog.

Abstract: A drug delivery system includes an atelocollagen-[aptamer-drug] complex which is prepared by mixing an aptamer-drug conjugate comprised of an aptamer and a drug attached to the aptamer with an atelocollagen dispersion. The aptamer is selected from the group consisting of AS1411, CRO, and ERBB2, and the drug is selected from the group consisting of Gemcitabine, Doxorubicin, and siRNA. An anticancer composition including the drug delivery system can compensate for shortcomings of existing anticancer agents and anticancer therapies.