Related Experiment Video
Updated: Jul 18, 2025
A Flow Cytometry-Based Cell Surface Protein Binding Assay for Assessing Selectivity and Specificity of an Anticancer Aptamer
Published on: September 13, 2022
A truncated DNA aptamer with high selectivity for estrogen receptor-positive breast cancer cells
Ying Cong1, Shu-Yue Zhang2, Hong-Mei Li1
1State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China.
Abstract:
The estrogen receptor-positive (ER+) breast cancers constitute more than 50 % of breast cancers, seriously threatening the health of women. Unfortunately, the detection and targeted therapy of ER+ breast cancers remain a challenge. Here, a novel nucleic acid aptamer S1-4 was developed to specifically target ER+ breast cancer MCF-7 cells by using Cell-SELEX and nucleic acid truncation strategies. The affinity dissociation constant of the binding of aptamer S1-4 to MCF-7 cells was 97.6 ± 7.5 nM in vitro. Compared with HER2+ breast cells SK-BR-3 and triple-negative breast cancer cells MDA-MB-231, MCF-7 cells were selectively recognized and targeted by aptamer S1-4. Fluorescence tracing in vivo results also indicated that aptamer S1-4 selectively targeted the cell membrane of tumor tissues in MCF-7- but not in SK-BR3 or MDB-MA-231-bearing mice. This selectively developed novel aptamer probe S1-4 with high affinity could be used for the diagnosis and treatment of ER+ breast cancers.
Insights
A new aptamer, S1-4, selectively targets estrogen receptor-positive (ER+) breast cancer cells. This high-affinity aptamer shows promise for improved diagnosis and targeted therapy of ER+ breast cancers.
Area of Science:
- Biomedical Engineering
- Molecular Biology
- Oncology
Background:
- Estrogen receptor-positive (ER+) breast cancers account for over 50% of all breast cancer cases.
- Effective detection and targeted therapy for ER+ breast cancer remain significant clinical challenges.
Purpose of the Study:
- To develop a novel nucleic acid aptamer for specific targeting of ER+ breast cancer cells.
- To evaluate the affinity and selectivity of the developed aptamer for diagnostic and therapeutic applications.
Main Methods:
- Cell-SELEX (Systematic Evolution of Ligands by Exponential Enrichment) and nucleic acid truncation strategies were employed to develop the aptamer.
- In vitro binding assays were performed to determine the affinity of the aptamer for target cells.
- In vivo fluorescence tracing was conducted in mice bearing different breast cancer cell types to assess tumor targeting selectivity.
Main Results:
- A novel nucleic acid aptamer, S1-4, was successfully developed.
- Aptamer S1-4 demonstrated high affinity for ER+ breast cancer MCF-7 cells with a dissociation constant (Kd) of 97.6 ± 7.5 nM.
- S1-4 exhibited selective targeting of MCF-7 cells over HER2+ (SK-BR-3) and triple-negative (MDA-MB-231) breast cancer cells in vitro and in vivo.
Conclusions:
- The novel aptamer S1-4 exhibits high affinity and selectivity for ER+ breast cancer cells.
- Aptamer S1-4 holds potential as a diagnostic and therapeutic probe for ER+ breast cancers.
