Khatami Fatemeh, Larijani Bagher, Nasiri Shirzad, Tavangar Seyed Mohammad
Chronic Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
Int J Mol Cell Med. 2019 Winter;8(Suppl1):19-29. doi: 10.22088/IJMCM.BUMS.8.2.19. Epub 2019 May 29.
In the blood of cancer patients, some nucleic acid fragments and tumor cells can be found that make it possible to trace tumor changes through a simple blood test called "liquid biopsy". The main components of liquid biopsy are fragments of DNA and RNA shed by tumors into the bloodstream and circulate freely (ctDNAs and ctRNAs). Tumor cells which are shed into the blood (circulating tumor cells or CTCs), and exosomes that have been investigated for non-invasive detection and monitoring several tumors including thyroid cancer. Genetic and epigenetic alterations of a thyroid tumor can be a driver for tumor genesis or essential for tumor progression and invasion. Liquid biopsy can be real-time representative of such genetic and epigenetic alterations to trace tumors. In thyroid tumors, the circulating mutation is now taken into account for both thyroid cancer diagnosis and determination of the most effective treatment strategy. Several recent studies have indicated the ctDNA methylation pattern of some iodine transporters and DNA methyltransferase as a diagnostic and prognostic biomarker in thyroid cancer as well. There has been a big hope that the recent advances of genome sequencing together with liquid biopsy can be a game changer in oncology.
在癌症患者的血液中，可以发现一些核酸片段和肿瘤细胞，这使得通过一种名为“液体活检”的简单血液检测来追踪肿瘤变化成为可能。液体活检的主要成分是肿瘤脱落到血液中并自由循环的DNA和RNA片段（循环肿瘤DNA和循环肿瘤RNA）。脱落到血液中的肿瘤细胞（循环肿瘤细胞或CTCs），以及已被研究用于包括甲状腺癌在内的多种肿瘤的无创检测和监测的外泌体。甲状腺肿瘤的基因和表观遗传改变可能是肿瘤发生的驱动因素，或者是肿瘤进展和侵袭所必需的。液体活检可以实时代表此类基因和表观遗传改变以追踪肿瘤。在甲状腺肿瘤中，循环突变现在已被用于甲状腺癌的诊断和最有效治疗策略的确定。最近的几项研究表明，一些碘转运体和DNA甲基转移酶的循环肿瘤DNA甲基化模式也可作为甲状腺癌的诊断和预后生物标志物。人们一直寄予厚望，基因组测序与液体活检的最新进展能够成为肿瘤学领域的变革力量。
