Therefore, to further confirm these data, the selective binding capability of the EpCAM ALB aptamer, antibody, random sequence and mutant against EpCAM-positive cancer cells and negative cancer cells were used to measure the percentage of expression in the MDA-MB-231 and Kato III cell lines (Figure 3A), and the percentage of positive signals obtained with the QD565-labeled ALB aptamer increased accordingly from 1.2% to 98.8% (Figure 3B). The gene discussed is ALB; the disease is cancer.