Ratio-tunable nucleic acid nanohybrids enable precision therapy for esophageal squamous cell carcinoma

Abstract Esophageal squamous cell carcinoma (ESCC) progression is strongly associated with the overexpression of bromodomain-containing protein 4 (BRD4) and syndecan-binding protein (SDCBP), identifying them as promising therapeutic targets. Conventional inhibitors, however, are frequently constrained by off-target effects and insufficient tumor specificity. Gene therapy, with nucleic acid drugs as its core, offers the advantage of directly modulating disease-causing gene expression, therefore overcoming these limitations. Therefore, this study aims to develop a multifunctional nucleic acid nanohybrid integrating an ESCC-specific aptamer, BRD4 DNAzyme (BDz), and SDCBP DNAzyme (SDz) for tumor-targeted therapy. This nanohybrid is engineered to respond to the acidic lysosomal environment by releasing BDz and SDz, enabling dual gene silencing, while tumor-specific delivery is mediated by the aptamer. Systematic adjustment of the molar ratios of BDz, SDz, and aptamer A components revealed that a 3:2:1 ratio produced optimal antitumor efficacy. This approach establishes a tunable-ratio dual-DNAzyme delivery platform that maximizes synergistic therapeutic effects while balancing targeted delivery with effective gene silencing, achieving precise dual-target therapy against ESCC. The results provide a base for the development of customizable multifunctional precision gene therapies.