School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China.
Henan Provincial Cooperative Innovation Center for Cancer Chemoprevention, Zhengzhou 450001, China.
Int J Mol Sci. 2024 Jul 21;25(14):7959. doi: 10.3390/ijms25147959.
Esophageal cancer ranks the seventh in cancer incidence and the sixth in cancer death. Esophageal squamous cell carcinoma (ESCC) accounts for approximately 90% of the total cases of esophageal cancer. Chemotherapy is the most effective drug-based method for treatment of esophageal cancer. However, severe side effects of traditional chemotherapy limit its treatment efficacy. Targeted chemotherapy can deliver chemotherapeutic drugs to cancer cells and specifically kill these cells with reduced side effects. In the work, the bivalent aptamer-DNA carrier (BAD) was designed by using an ESCC cell-specific aptamer as the recognition molecule and a GC base-rich DNA sequence as the drug carrier. With doxorubicin (Dox) as chemotherapeutic drugs, the bivalent aptamer-DNA-Dox conjugate (BADD) was constructed for targeted killing of ESCC cells. Firstly, the truncated A2(35) aptamer with a retained binding ability was obtained through optimization of an intact A2(80) aptamer and was used to fuse with DNA carrier sequences for constructing the BAD through simple DNA hybridization. The results of gel electrophoresis and flow cytometry analysis showed that the BAD was successfully constructed and had a stronger binding affinity than monovalent A2(35). Then, the BAD was loaded with Dox drugs to construct the BADD through noncovalent intercalation. The results of fluorescence spectra and flow cytometry assays showed that the BADD was successfully constructed and can bind to target cells strongly. Confocal imaging further displayed that the BADD can be specifically internalized into target cells and release Dox. The results of CCK-8 assays, Calcein AM/PI staining, and wound healing assays demonstrated that the BADD can specifically kill target cells, but not control cells. Our results demonstrate that the developed BADD can specifically deliver doxorubicin to target ESCC cells and selectively kill these cells, offering a potentially effective strategy for targeted chemotherapy of ESCC.
食管癌的发病率位居癌症第七位，死亡率位居癌症第六位。食管鳞状细胞癌（ESCC）约占食管癌总病例的 90%。化疗是治疗食管癌最有效的药物方法。然而，传统化疗的严重副作用限制了其治疗效果。靶向化疗可以将化疗药物递送到癌细胞中，并特异性地杀死这些细胞，同时减少副作用。在这项工作中，设计了双价适体-DNA 载体（BAD），使用 ESCC 细胞特异性适体作为识别分子，GC 碱基丰富的 DNA 序列作为药物载体。以阿霉素（Dox）作为化疗药物，构建了双价适体-DNA-Dox 缀合物（BADD），用于靶向杀伤 ESCC 细胞。首先，通过优化完整的 A2(80)适体，获得了保留结合能力的截短 A2(35)适体，并将其与 DNA 载体序列融合，通过简单的 DNA 杂交构建 BAD。凝胶电泳和流式细胞术分析结果表明，BAD 成功构建，且具有比单价 A2(35)更强的结合亲和力。然后，通过非共价嵌入将 BAD 加载 Dox 药物，构建 BADD。荧光光谱和流式细胞术检测结果表明，BADD 成功构建，能够与靶细胞强烈结合。共聚焦成像进一步显示，BADD 可以特异性地内化到靶细胞中并释放 Dox。CCK-8 检测、Calcein AM/PI 染色和划痕愈合检测结果表明，BADD 可以特异性杀死靶细胞，而对对照细胞无影响。我们的结果表明，所开发的 BADD 可以特异性地将阿霉素递送到靶 ESCC 细胞，并选择性地杀死这些细胞，为 ESCC 的靶向化疗提供了一种潜在有效的策略。
