scholarly journals A Study of Hypermethylated Circulating Tumor DNA as a Universal Colorectal Cancer Biomarker

2016 ◽  
Vol 62 (8) ◽  
pp. 1129-1139 ◽  
Author(s):  
Sonia Garrigou ◽  
Geraldine Perkins ◽  
Fanny Garlan ◽  
Corinne Normand ◽  
Audrey Didelot ◽  
...  

Abstract BACKGROUND Circulating tumor DNA (ctDNA) has emerged as a good candidate for tracking tumor dynamics in different cancer types, potentially avoiding repeated tumor biopsies. Many different genes can be mutated within a tumor, complicating procedures for tumor monitoring, even with highly sensitive next-generation sequencing (NGS) strategies. Droplet-based digital PCR (dPCR) is a highly sensitive and quantitative procedure, allowing detection of very low amounts of circulating tumor genetic material, but can be limited in the total number of target loci monitored. METHODS We analyzed hypermethylation of 3 genes, by use of droplet-based dPCR in different stages of colorectal cancer (CRC), to identify universal markers for tumor follow-up. RESULTS Hypermethylation of WIF1 (WNT inhibitory factor 1) and NPY (neuropeptide Y) genes was significantly higher in tumor tissue compared to normal tissue, independently of tumor stage. All tumor tissues appeared positive for one of the 2 markers. Methylated ctDNA (MetctDNA) was detected in 80% of metastatic CRC and 45% of localized CRC. For samples with detectable mutations in ctDNA, MetctDNA and mutant ctDNA (MutctDNA) fractions were correlated. During follow-up of different stage CRC patients, MetctDNA changes allowed monitoring of tumor evolution. CONCLUSIONS These results indicate that MetctDNA could be used as a universal surrogate marker for tumor follow-up in CRC patients, and monitoring MetctDNA by droplet-based dPCR could avoid the need for monitoring mutations.

2016 ◽  
Vol 34 (4_suppl) ◽  
pp. 622-622
Author(s):  
Geraldine Perkins ◽  
Sonia Garrigou ◽  
Fanny Garlan ◽  
Corinne Normand ◽  
Audrey Didelot ◽  
...  

622 Background: Circulating tumor DNA (ctDNA) is thoroughly investigated as a surrogate biomarker of tumor follow-up, in different cancer types, such as colorectal cancer (CRC). Droplet-based digital PCR (ddPCR) is a highly sensitive and also quantitative method for detection of very low amount of ctDNA. Since many different genes can be mutated within a specific tumor type and also wide mutation spectrum can occur within a specific gene, procedures for ctDNA monitoring can be time consuming and need to be improved for a routinely use. To overcome these drawbacks, we characterized the methylation status of 3 genes frequently hypermethylated in CRC to identify universal markers for tumor follow-up. Methods: The characterization of the methylated status of the WIF, NPY and PENK genes in the tumor DNA was performed in 56 CRC of different stages and 45 corresponding plasma samples using droplet-based dPCR, after DNA bisulfite conversion. A two-panels assay (with albumin as a reference) was developed. Methylation level of these 3 genes in tumor tissues was compared to corresponding normal tissues (n = 22) and plasma samples (MetctDNA). To validate, plasma samples of additional 91 patients were analyzed for the presence of ctDNA both by the characterization of KRAS, BRAF, TP53 and PIK3CA mutations (MutctDNA) and of MetctDNA, at various stages of their follow-up, and 9 of them had MetctDNA assessment during treatment follow-up. Results: All tumor samples were positive for WIF1 and/or NPY markers. Hypermethylation of these two genes was significantly higher in tumor tissue compared to normal, independently of the tumor stage (p < 0.0001). MetctDNA could be detected in 75% of metastatic CRC patients and 24% of localized CRC patients (stage 1 to 3). MetctDNA and MutctDNA fractions were strongly correlated (R2 > 0.9, p < 0.0001). During follow-up, MetctDNA levels changes allowed monitoring of tumor evolution in different stages CRC patients. Conclusions: These results indicate that determination of MetctDNA by droplet-based dPCR can reach same efficiency than MutctDNA for ctDNA assessment, using only 2 markers, and thus could be considered as a universal surrogate marker of tumor follow-up in CRC patients.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anaïs Prouteau ◽  
Jérôme Alexandre Denis ◽  
Pauline De Fornel ◽  
Edouard Cadieu ◽  
Thomas Derrien ◽  
...  

AbstractCirculating tumor DNA (ctDNA) has become an attractive biomarker in human oncology, and its use may be informative in canine cancer. Thus, we used droplet digital PCR or PCR for antigen receptor rearrangement, to explore tumor-specific point mutations, copy number alterations, and chromosomal rearrangements in the plasma of cancer-affected dogs. We detected ctDNA in 21/23 (91.3%) of histiocytic sarcoma (HS), 2/8 (25%) of oral melanoma, and 12/13 (92.3%) of lymphoma cases. The utility of ctDNA in diagnosing HS was explored in 133 dogs, including 49 with HS, and the screening of recurrent PTPN11 mutations in plasma had a specificity of 98.8% and a sensitivity between 42.8 and 77% according to the clinical presentation of HS. Sensitivity was greater in visceral forms and especially related to pulmonary location. Follow-up of four dogs by targeting lymphoma-specific antigen receptor rearrangement in plasma showed that minimal residual disease detection was concordant with clinical evaluation and treatment response. Thus, our study shows that ctDNA is detectable in the plasma of cancer-affected dogs and is a promising biomarker for diagnosis and clinical follow-up. ctDNA detection appears to be useful in comparative oncology research due to growing interest in the study of natural canine tumors and exploration of new therapies.


2021 ◽  
Vol 14 (2) ◽  
pp. 128
Author(s):  
Silvia Galbiati ◽  
Francesco Damin ◽  
Dario Brambilla ◽  
Lucia Ferraro ◽  
Nadia Soriani ◽  
...  

It is widely accepted that assessing circular tumor DNA (ctDNA) in the plasma of cancer patients is a promising practice to evaluate somatic mutations from solid tumors noninvasively. Recently, it was reported that isolation of extracellular vesicles improves the detection of mutant DNA from plasma in metastatic patients; however, no consensus on the presence of dsDNA in exosomes has been reached yet. We analyzed small extracellular vesicle (sEV)-associated DNA of eleven metastatic colorectal cancer (mCRC) patients and compared the results obtained by microarray and droplet digital PCR (ddPCR) to those reported on the ctDNA fraction. We detected the same mutations found in tissue biopsies and ctDNA in all samples but, unexpectedly, in one sample, we found a KRAS mutation that was not identified either in ctDNA or tissue biopsy. Furthermore, to assess the exact location of sEV-associated DNA (outside or inside the vesicle), we treated with DNase I sEVs isolated with three different methodologies. We found that the DNA inside the vesicles is only a small fraction of that surrounding the vesicles. Its amount seems to correlate with the total amount of circulating tumor DNA. The results obtained in our experimental setting suggest that integrating ctDNA and sEV-associated DNA in mCRC patient management could provide a complete real-time assessment of the cancer mutation status.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e23025-e23025
Author(s):  
Yuji Takayama ◽  
Koichi Suzuki ◽  
Kosuke Ichida ◽  
Taro Fukui ◽  
Fumiaki Watanabe ◽  
...  

e23025 Background: Emergence of KRAS mutation in blood is observed in colorectal cancer patients who undergo chemotherapy, but its clinical significance is not well known. In this study, we focused on the difference in appearance of KRAS mutated circulating tumor DNA (MctDNA) and elucidated its association with treatments. Methods: Four hundred and fifty-one plasma samples were collected prospectively from 85 patients (pts) who underwent chemotherapy due to metastatic colorectal cancer in 2014 - 2016. Seven types of KRAS mutation in MctDNA were detected by droplet digital PCR creating oil droplets. To exclude false positive detection, mutation was validated. MctDNA amplified in oil droplets was selectively sorted by On-chip sorting system and mutation was determined by Sanger sequencing. Results: KRAS assessment in tumor tissues showed 29 pts with KRAS mutation (MT), 56 pts without KRAS mutation (WT). Among 29 pts with MT, KRAS assessment in plasma displayed 23 pts with MctDNA and 6 pts without MctDNA. The type of mutation in MctDNA was consistent with that detected in tumor tissues, indicating mutual exclusivity in KRAS mutation was confirmed. In 56 pts with WT, 28 pts showed MctDNA during treatments. Difference in appearance of MctDNA was recognized in several treatments. Gradual increase in detection of MctDNA was observed with anti-EGFR antibody, resulted in treatment resistance. Transient spike elevation was frequently seen in TAS-102, which associated with drug response. No specific appearance was recognized during treatments with other drugs including anti-VEGF antibody. MctDNA in oil droplets were successfully sorted even if a few droplets were targeted, and mutation was confirmed. Conclusions: Difference in appearance of MctDNA may associate with treatment response in patients with metastatic colorectal cancer during treatments. [Table: see text]


Cancers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2914 ◽  
Author(s):  
Alessandra Sacco ◽  
Laura Forgione ◽  
Marianeve Carotenuto ◽  
Antonella De Luca ◽  
Paolo A. Ascierto ◽  
...  

Malignant melanoma accounts for about 1% of all skin cancers, but it causes most of the skin cancer-related deaths. Circulating tumor DNA (ctDNA) testing is emerging as a relevant tool for the diagnosis and monitoring of cancer. The availability of highly sensitive techniques, including next generation sequencing (NGS)-based panels, has increased the fields of application of ctDNA testing. While ctDNA-based tests for the early detection of melanoma are not available yet, perioperative ctDNA analysis in patients with surgically resectable melanoma offers relevant prognostic information: i) the detection of ctDNA before surgery correlates with the extent and the aggressiveness of the disease; ii) ctDNA testing after surgery/adjuvant therapy identifies minimal residual disease; iii) testing ctDNA during the follow-up can detect a tumor recurrence, anticipating clinical/radiological progression. In patients with advanced melanoma, several studies have demonstrated that the analysis of ctDNA can better depict tumor heterogeneity and provides relevant prognostic information. In addition, ctDNA testing during treatment allows assessing the response to systemic therapy and identifying resistance mechanisms. Although validation in prospective clinical trials is needed for most of these approaches, ctDNA testing opens up new scenarios in the management of melanoma patients that could lead to improvements in the diagnosis and therapy of this disease.


2020 ◽  
Vol 66 (12) ◽  
pp. 1510-1520
Author(s):  
Smiths S Lueong ◽  
Andreas Herbst ◽  
Sven-Thorsten Liffers ◽  
Nicola Bielefeld ◽  
Peter A Horn ◽  
...  

Abstract Background We assessed the usefulness of circulating tumor DNA (ctDNA) pre- or post-treatment initiation for outcome prediction and treatment monitoring in metastatic colorectal cancer (mCRC). Methods Droplet digital PCR was used to measure absolute mutant V-Ki-ras2 Kirsten rat sarcoma viral oncogene ((mut)KRAS) ctDNA concentrations in 214 healthy controls (plasma and sera) and in 151 tissue-based mutKRAS positive patients with mCRC from the prospective multicenter phase 3 trial AIO KRK0207. Serial mutKRAS ctDNA was analyzed prior to and 2–3 weeks after first-line chemotherapy initiation with fluoropyrimidine, oxaliplatin, and bevacizumab in patients with mCRC and correlated with clinical parameters. Results mut KRAS ctDNA was detected in 74.8% (113/151) of patients at baseline and in 59.6% (90/151) at follow-up. mutKRAS ctDNA at baseline and follow-up was associated with poor overall survival (OS) (hazard ratio [HR] =1.88, 95% confidence interval [CI] 1.20–2.95; HR = 2.15, 95% CI 1.47–3.15) and progression-free survival (PFS) (HR = 2.53, 95% CI 1.44–4.46; HR = 1.90, 95% CI 1.23–2.95), respectively. mutKRAS ctDNA clearance at follow-up conferred better disease control (P = 0.0075), better OS (log-rank P = 0.0018), and PFS (log-rank P = 0.0018). Measurable positive mutKRAS ctDNA at follow-up was the strongest and most significant independent prognostic factor on OS in multivariable analysis (HR = 2.31, 95% CI 1.40–3.25). Conclusions Serial analysis of circulating mutKRAS concentrations in mCRC has prognostic value. Post treatment mutKRAS concentrations 2 weeks after treatment initiation were associated with therapeutic response in multivariable analysis and may be an early response predictor in patients receiving first-line combination chemotherapy. Clinicaltrialsgov Identifier NCT00973609.


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