Department of Hepatology, St Mary's Hospital, Imperial College, London, UK; Centre for Population Health, MacFarlane-Burnet Institute, Melbourne, Australia; Department of Medicine, The University of Melbourne, Melbourne, Australia.
Department of Hepatology, St Mary's Hospital, Imperial College, London, UK.
Transl Res. 2017 May;183:137-154. doi: 10.1016/j.trsl.2016.12.006. Epub 2016 Dec 22.
Circulating cell-free DNA (cfDNA) is DNA released from necrotic or apoptotic cells into the bloodstream. While both healthy cells and cancer cells release cfDNA, tumors are associated with higher levels of tumor-derived circulating cell-free DNA (ctDNA) detectable in blood. Absolute levels of ctDNA and its genetic mutations and epigenetic changes show promise as potentially useful biomarkers of tumor biology, progression, and response to therapy. Moreover, studies have demonstrated the discriminative accuracy of ctDNA levels for diagnosis of gastrointestinal cancer compared with benign inflammatory diseases. Therefore, ctDNA detected in blood offers a minimally invasive and easily repeated "liquid biopsy" of cancer, facilitating real-time dynamic analysis of tumor behavior that could revolutionize both clinical and research practices in oncology. In this review, we provide a critical summary of the evidence for the utility of ctDNA as a diagnostic and prognostic biomarker in gastrointestinal malignancies.
循环游离 DNA（cfDNA）是从坏死或凋亡细胞释放到血液中的 DNA。虽然健康细胞和癌细胞都会释放 cfDNA，但肿瘤与血液中可检测到的肿瘤来源的循环游离 DNA（ctDNA）水平更高有关。ctDNA 的绝对水平及其遗传突变和表观遗传变化显示出作为肿瘤生物学、进展和对治疗反应的潜在有用生物标志物的潜力。此外，研究已经证明了 ctDNA 水平在诊断胃肠道癌症与良性炎症性疾病相比的区分准确性。因此，血液中检测到的 ctDNA 提供了一种微创且易于重复的“液体活检”癌症方法，促进了对肿瘤行为的实时动态分析，这可能彻底改变肿瘤学的临床和研究实践。在这篇综述中，我们对 ctDNA 作为胃肠道恶性肿瘤的诊断和预后生物标志物的效用提供了批判性总结。
