Department of cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang 110122, PR China.
Department of cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang 110122, PR China; Analytical Instrumentation Center, Shenyang Agricultural University, Shenyang 110001, PR China.
Talanta. 2019 Jul 1;199:634-642. doi: 10.1016/j.talanta.2019.03.016. Epub 2019 Mar 2.
Gastric cancer (GC) is associated with high morbidity and mortality rates worldwide. Poorly differentiated GC predicts a poor prognosis and is related to patients' response to chemotherapy and targeted therapy. Therefore, it is very important to accurately evaluate the tumour differentiation status for the treatment of poorly differentiated GC. To develop a molecular probe to analyse poorly differentiated GC, we selected aptamers against poorly differentiated GC by subtractive Cell-SELEX using the poorly differentiated GC cell line BGC-823 as the target and the moderately differentiated GC cell line SGC-7901 as the negative control. After 15 rounds of selection, aptamer PDGC21 exhibited the highest affinity, and the K value of the truncated aptamer PDGC21-T was 35.2 ± 1.1 nM. Aptamer PDGC21-T not only specifically bound to the target cells but also bound to other poorly differentiated GC cells. When combined with fluorescent nanoparticle quantum dots (QDs), the PDGC21-T-QD probe could distinguish poorly differentiated GC cells in mixed culture cells and clinical specimens. Furthermore, in a tissue microarray containing 15 cases from patients, there was a higher positive rate in GC tissues compared with adjacent normal tissues; in poorly differentiated tissues, in particular, the fluorescence signal was significantly higher than that in well/moderately differentiated tissues. Therefore, aptamer PDGC21-T holds great potential for use as a molecular imaging probe for the detection of poorly differentiated GC, which is of great significance for diagnosis and treatment.
胃癌（GC）在全球范围内与高发病率和死亡率相关。低分化 GC 预示着预后不良，与患者对化疗和靶向治疗的反应有关。因此，准确评估肿瘤分化状态对于治疗低分化 GC 非常重要。为了开发一种分析低分化 GC 的分子探针，我们使用低分化 GC 细胞系 BGC-823 作为靶标和中分化 GC 细胞系 SGC-7901 作为阴性对照，通过减法 Cell-SELEX 选择针对低分化 GC 的适体。经过 15 轮筛选，适体 PDGC21 表现出最高的亲和力，截断适体 PDGC21-T 的 K 值为 35.2±1.1 nM。适体 PDGC21-T 不仅特异性地与靶细胞结合，还与其他低分化 GC 细胞结合。当与荧光纳米颗粒量子点 (QDs) 结合时，PDGC21-T-QD 探针可以区分混合培养细胞和临床标本中的低分化 GC 细胞。此外，在包含 15 例患者的组织微阵列中，GC 组织的阳性率高于相邻正常组织；特别是在低分化组织中，荧光信号明显高于高/中分化组织。因此，适体 PDGC21-T 有可能作为低分化 GC 的分子成像探针，对于诊断和治疗具有重要意义。
