# DNA Aptamers: Reloaded Tools for Breast Cancer Therapeutics

## TL;DR

This paper reviews how DNA aptamers can improve breast cancer diagnostics and treatment, especially in regions with limited access to advanced therapies.

## Contribution

The paper provides a comprehensive review of recent advances in aptamer-based theranostics for breast cancer.

## Key findings

- Aptamers offer advantages like low immunogenicity and scalable synthesis for cancer targeting.
- Aptamers enable sensitive diagnostics and targeted drug delivery through biosensors and nanomedicine.
- Aptamers may democratize precision oncology in regions with limited access to advanced technologies.

## Abstract

Breast cancer is still a leading cause of mortality among women, mainly due to late detection, tumor heterogeneity, and limited access to advanced therapies. Therefore, there is a need for precise, reproducible, and affordable tools for diagnostics and therapeutics. Aptamers—synthetic single-stranded oligonucleotides that fold into specific three-dimensional structures—offer high affinity and selectivity for cancer targets, with advantages such as low immunogenicity, chemical stability, and scalable synthesis. This review summarizes recent progress in the use of aptamers for breast cancer, including biosensors and liquid biopsy applications, prognostic profiling of aggressive subtypes, and therapeutic conjugates such as aptamer–drug and aptamer–siRNA combinations. Upon overcoming current challenges in pharmacokinetics and clinical validation, aptamers should become transformative tools for breast cancer by enabling precision oncology and broad accessibility.

Breast cancer continues to be a major challenge in global health, in part due to significant inequalities in access to costly diagnostic and therapeutic technologies based on antibodies. Their manufacturing requires complex and expensive bioproduction systems, resulting in limited availability of these tools—essential for early detection and targeted treatment—in many regions, particularly in Latin America. This gap has highlighted the need for cost-effective and scalable theranostic alternatives, increasing interest in aptamers. Obtained through SELEX technology, aptamers are synthetic DNA or RNA oligomers that fold into functional structures. Among their advantages are high affinity for their target, low immunogenicity, and chemical synthesis, which assures reproducible production. Aptamers have expanded the landscape of diagnostic platforms through the development of sensitive aptasensors, liquid biopsy strategies, and imaging systems based on nanomedicines. They also contribute to targeted therapy by recognizing cancer biomarkers selectively and enabling controlled drug delivery. This review presents a critical summary of advances in aptamer-based theranostics for breast cancer, addressing molecular mechanisms, structural folding, selective ligand binding, and nanomaterial interfacing. We also discuss applications in extracellular vesicle capture, cancer stem cell detection, and therapeutic conjugates, emphasizing their advantages and limitations relative to approaches based on antibodies. Overall, current advances show aptamers as emerging tools capable of democratizing precision oncology, particularly in regions where access to advanced technologies remains limited.