Abstract:
PURPOSE: A nucleic acid aptamer which specifically HER-2-overexpressing breast cancer cells or tissues is provided to enhance survival rate of breast cancer patients. CONSTITUTION: A nucleic acid aptamer of 15-60nts contains one nucleic acid of sequence numbers 9, 12, 13, and 17 and specifically binds to HER-2-overexpressing breast cancer cells or tissues. The nucleic acid aptamer includes chemical modification. The chemical modification is substitution of a hydroxyl group at ribose 2' site of a nucleotide into hydrogen atoms, fluorine, -O-alkyl group, -O-acyl group, or amino group. The nucleic acid aptamer is used for detecting breast cancer. A method for detecting breast cancer comprises a step of contacting the nucleic acid aptamer with breast tissue, breast cells, blood, serum, plasma, sputum, and urine.