A Novel Aptamer Developed for Breast Cancer Cell Internalization

Breast cancer affects one in eight women in the United States, with a mortality rate that is second only to lung cancer. Although chemotherapy is widely used in breast cancer treatment, its side effects remain a challenge. One way to address this problem is through drug delivery by the internalization of cell‐type‐specific probes. Although nucleic acid aptamers are excellent probes for molecular recognition, only a few studies have demonstrated that aptamers can be internalized into living cells. Therefore, herein we report the development of a cancer‐cell‐specific DNA aptamer probe, KMF2‐1a. By using the cell‐SELEX method, this aptamer was selected against breast cancer cell line MCF‐10AT1. Our results show that KMF2‐1a is internalized efficiently and specifically to the endosome of target breast cancer cells. These results indicate that KMF2‐1a is a promising agent for cell‐type‐specific intracellular delivery with both diagnostic and therapeutic implications.