Figure 1.

Schematic Illustration of HER2 Aptamer-EGFR siRNA-HER3 Aptamer, H2EH3, and Characterization of H2EH3

(A) Structure of H2EH3. HER2 aptamer was conjugated with HER3 aptamer through 21 bases of EGFR siRNA and 2–4 unpaired base linkers. (B) Western blot detection of the expression levels of HER2, HER3, and EGFR in a panel of breast cancer cell lines. (C) Evaluation of the cytotoxicity of H2EH3 by CCK-8 assay. Breast cancer cell lines, including BT474, SKBR3, MCF7, MDA-MB-231, and Hs587T cells, were treated with varying concentrations of H2EH3 or controls for 72 hr, and cell viability was detected with the CCK-8 agent. Data are the mean ± SD from three independent experiments. (D) Evaluation of EGFR-silencing capability of H2EH3 using western blot. (E) Evaluation of H2EH3-binding capability compared with HER2 aptamer and HER3 aptamer.