以深度標的基因定序血漿中DNA來鑑定泌尿道上皮細胞癌的突變
楊昀達、陳文祥、吳俊德、林政鋒、林承家
基隆長庚醫院 外科部 泌尿科
Identification of urothelial cancer mutations by targeted deep sequencing of plasma DNA
Yun-Ta Yang, Wen-Hsiang Chen, Chun-Te Wu, Cheng-Feng Lin, Cheng-Chia Lin
Divisions of Urology, Department of Surgery, Chang Gung Memorial Hospital, Keelung, Taiwan
Purpose: Repeat tumor biopsies to study genomic changes during therapy are difficult, invasive and data are confounded by tumoral heterogeneity. The analysis of circulating tumor DNA (ctDNA) can provide a non-invasive approach to assess prognosis and the genetic evolution of tumors in response to therapy. Circulating tumor DNA (ctDNA) is now being extensively studied as it is a noninvasive “real-time” biomarker that can provide diagnostic and prognostic information before, during treatment and at progression. Technologies Targeted plasma re-sequencing (TAm-Seq) were performed to variant cancers including pancreatic cancer, colorectal cancer, lung cancer and breast cancer. But in urothelial cancer did not have the investigation of the correlation between somatic mutation and ctDNA.
Materials and Methods: In this study, the NGS using Ion AmpliSeq™ Cancer Hotspot Panel v2 was performed to urothelial DNA samples from cancer tissue and plasma. The Ion AmpliSeq™ Cancer Hotspot Panel v2 (Ion Torrent), covering 2800 COSMIC mutations from 50 cancer genes was used to analyze 6 tumor and 6 plasma samples from 6 urothelial cancer patients. The targeted coverage for tumor DNA was ×1000 and for plasma cell-free DNA ×25 000.
Results and Conclusion: We found the liquid biopsy should be available in urothelial cancer. Almost variants found in urothelial cancer were also found in cell-free DNA. Some technical concern should be taken in future investigation, one is depth of sequencing, more variants should be found in higher depth sequencing; another is methods of variant analysis, robust and accuracy bioinformatics analysis should be developed to clinical application.