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bioRxiv · 10.64898/2026.06.11.730265

An EpCAM-Targeted Mirror-Image DNA Nanostructure for Precise Drug Delivery in Triple-Negative Breast Cancer

Wu, S.·Farkaly, T.·Zhang, W.
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Abstract

Triple-negative breast cancer (TNBC) remains a major therapeutic challenge due to the lack of effective molecular targets and the dose-limiting off-target toxicity of conventional chemotherapy. Here, we design and construct a mirror-image DNA (L-DNA) nanostructure functionalized with an epithelial cell adhesion molecule (EpCAM)-specific aptamer for targeted delivery of doxorubicin (DOX) to TNBC cells. The L-DNA nanostructure retains thermodynamic properties comparable to natural D-DNA while exhibiting substantially enhanced resistance to nuclease and serum-mediated degradation due to its mirror-image chirality. Thermal melting and serum stability assays confirmed superior structural stability of the L-DNA nanostructure compared to D-DNA counterparts. In vitro cytotoxicity studies demonstrated that the EpCAM-targeted L-DNA nanostructure has the potential to selectively inhibit the growth of EpCAM-positive TNBC cells while reducing cytotoxicity in normal cells. These findings demonstrate that combining aptamer targeting with mirror-image DNA nanotechnology provides a stable and selective nanoplatform for chemotherapeutic delivery, which can potentially improve the precision and therapeutic efficacy of treatment for aggressive breast cancers.

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Wu, S., Farkaly, T., Zhang, W.. 2026-06-15. An EpCAM-Targeted Mirror-Image DNA Nanostructure for Precise Drug Delivery in Triple-Negative Breast Cancer. https://doi.org/10.64898/2026.06.11.730265

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