Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi, Taiwan.
Department of Surgical Pathology, Changhua Christian Hospital, Changhua, Taiwan; College of Medicine, National Chung Hsiung University, Taichung, Taiwan.
Biosens Bioelectron. 2022 Oct 15;214:114540. doi: 10.1016/j.bios.2022.114540. Epub 2022 Jul 6.
A new innovative approach is essential for early and effective diagnosis of gastric cancer, using promoter hypermethylation of the tumor suppressor, SOCS-1, that is frequently inactivated in human cancers. We have developed an amplification-free fiber optic nanoplasmonic biosensor for detecting DNA methylation of the SOCS-1 human genome. The method is based on the fiber optic nanogold-linked sorbent assay of PCR-free DNA from human gastric tumor tissue and cell lines. We designed a specific DNA probe fabricated on the fiber core surface while the other probe is bioconjugated with gold nanoparticles in free form to allow percentage determination and differentiating the methylated and unmethylated cell lines, further demonstrating the SOCS-1 methylation occurs in cancer patients but not in normal cell lines. The observed detection limit is 0.81 fM for methylated DNA, and the detection time is within 15 min. In addition, our data were significantly correlated to the data obtained from PCR-based pyrosequencing, and yet with superior accuracy. Hence our results provide new insight to the quantitative evaluation of methylation status of the human genome and can act as an alternative to PCR with a great potential.
一种新的创新方法对于早期和有效的胃癌诊断至关重要，该方法利用肿瘤抑制因子 SOCS-1 的启动子超甲基化，SOCS-1 在人类癌症中经常失活。我们已经开发了一种无扩增的光纤纳米等离子体生物传感器，用于检测 SOCS-1 人类基因组的 DNA 甲基化。该方法基于光纤纳米金连接的无 PCR 人类胃肿瘤组织和细胞系的 DNA 吸附测定。我们设计了一种特定的 DNA 探针，将其制造在光纤芯表面上，而另一种探针则以游离形式与金纳米颗粒结合，以允许进行百分比测定并区分甲基化和非甲基化的细胞系，进一步证明 SOCS-1 甲基化发生在癌症患者中，但不在正常细胞系中。观察到的检测限为 0.81 fM 的甲基化 DNA，检测时间在 15 分钟内。此外，我们的数据与基于 PCR 的焦磷酸测序获得的数据显著相关，但准确性更高。因此，我们的结果为人类基因组甲基化状态的定量评估提供了新的见解，并有可能替代 PCR。
