Cell-free DNA and exoDNA analysis in metastatic colorectal cancer patients (mCRC).

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e16093-e16093
Author(s):  
Antonio Galvano ◽  
Marta Castiglia ◽  
Aurelia Guarini ◽  
Valerio Gristina ◽  
Sofia Cutaia ◽  
...  

e16093 Background: Liquid biopsy is a growing field in translational cancer research. Two of the most studied liquid biopsy biomarkers are cell-free DNA (cfDNA) and exosomes, nano-sized vesicles that transport protein and nucleic acids including DNA (exoDNA). Therefore, both cfDNA and exoDNA are potentially useful to investigate the molecular landscape of tumor with a minimally invasive approach. Here we investigate the prognostic and predictive role of both cfDNA and exoDNA in mCRC using Next Generation Sequencing (NGS) analysis. Methods: From July 2017 to September 2018, samples of 40 mCRC patients were collected at the Medical Oncology of the AOUP Paolo Giaccone of Palermo. Blood samples were collected in EDTA-tubes before chemotherapy infusion (T1), at the first instrumental evaluation (T2) and every 2-3 months (T3). Plasma was used to isolate cfDNA and exosomes using the QIAamp Circulating Nucleic Acid and ExoEasy Maxi Kit respectively. ExoDNA was isolated through the QIAamp DNA micro kit. NGS analysis was conducted on IonS5 with AmpliSeq Cancer Hotspot Panel v2, which includes hotspot regions of 50 cancer-related genes. Results: Patients with cfDNA concentration > 0.47ng/μl have worse PFS compared with those with < 0.47 ng/μl cfDNA level. NGS analysis from 16 cfDNA samples showed a total of 292 mutations, with a median of 5 non-synonymous mutations in T1 vs. 8 non-synonymous mutations in T2 sample. We report an inverse and significant correlation between non-synonymous mutations count and disease-specific survival (DSS). Only 2 cfDNA samples carried KRAS mutations, despite it were previously reported in 5 paired tissue samples. An interesting result emerged from exoDNA sequencing of CRC20. KRAS mutation was identified in T1 exoDNA but not in the paired cfDNA samples, suggesting that exoDNA is able to intercept KRAS mutation earlier than cfDNA. Conclusions: cfDNA analysis could be a useful tool for better patients’ stratification. exoDNA could allow an early interception of disease recurrence that could be explained by the ability of exosomes to protect their cargo from degradation.

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Alexander Hendricks ◽  
Philip Rosenstiel ◽  
Sebastian Hinz ◽  
Greta Burmeister ◽  
Christoph Röcken ◽  
...  

Abstract Background Liquid biopsies of blood plasma cell free DNA can be used to monitor treatment response and potentially detect mutations that are present in resistant clones in metastatic cancer patients. Case presentation In our non-interventional liquid biopsy study, a male patient in his fifties diagnosed with stage IV colorectal cancer and polytope liver metastases rapidly progressed after completing chemotherapy and deceased 8 months after diagnosis. Retrospective cell free DNA testing showed that the APC/TP53/KRAS major clone responded quickly after 3 cycles of FOLFIRI + Bevacizumab. Retrospective exome sequencing of pre-chemotherapy and post-chemotherapy tissue samples including metastases confirmed that the APC/TP53/KRAS and other major clonal mutations (GPR50, SLC5A, ZIC3, SF3A1 and others) were present in all samples. After the last chemotherapy cycle, CT imaging, CEA and CA19–9 markers validated the cfDNA findings of treatment response. However, 5 weeks later, the tumour had rapidly progressed. Conclusion As FOLFIRI+Bevacizumab has recently also been associated with sustained complete remission in a APC/TP53/KRAS triple-mutated patient, these driver genes should be tested and monitored in a more in-depth manner in future patients. Patients with metastatic disease should be monitored more closely during and after chemotherapy, ideally using cfDNA.


2018 ◽  
Vol 64 (4) ◽  
pp. 726-734 ◽  
Author(s):  
Min Kyeong Kim ◽  
Sang Myung Woo ◽  
Boram Park ◽  
Kyong-Ah Yoon ◽  
Yun-Hee Kim ◽  
...  

Abstract BACKGROUND Cell-free DNA (cfDNA) is known to provide potential biomarkers for predicting clinical outcome, but its value in pancreatic ductal adenocarcinoma (PDAC) has not been fully evaluated. The aim of this study was to evaluate the clinical applicability of quantitative analysis of multiplex KRAS mutations in cell-free DNA from patients with PDAC. METHODS A total of 106 patients with PDAC were enrolled in this prospective study. The concentration and fraction of KRAS mutations were determined through multiplex detection of KRAS mutations in plasma samples by use of a droplet digital PCR kit (Bio-Rad). RESULTS KRAS mutations were detected in 96.1% of tissue samples. Eighty patients (80.5%) harbored KRAS mutations in cfDNA, with a median KRAS mutation concentration of 0.165 copies/μL and a median fractional abundance of 0.415%. Multivariable analyses demonstrated that the KRAS mutation concentration [hazard ratio (HR), 2.08; 95% CI, 1.20–3.63] and KRAS fraction (HR, 1.73; 95% CI, 1.02–2.95) were significant factors for progression-free survival. KRAS mutation concentration (HR, 1.97; 95% CI, 1.05–3.67) also had prognostic implications for overall survival. Subgroup analyses showed that KRAS mutation concentration and fractional abundance significantly affected progression-free survival in resectable PDAC (P = 0.016). Moreover, when combined with the cancer biomarker CA19-9, the KRAS mutation concentration in cfDNA showed additive benefits for the prediction of overall survival. CONCLUSIONS This study demonstrates that multiplex detection of KRAS mutations in plasma cfDNA is clinically relevant, providing a potential candidate biomarker for prognosis of PDAC.


Cancers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 39
Author(s):  
Caroline Driescher ◽  
Katharina Fuchs ◽  
Lena Haeberle ◽  
Wolfgang Goering ◽  
Lisa Frohn ◽  
...  

Currently available serum biomarkers for pancreatobiliary cancers lack sensitivity and specificity and ultimate diagnosis still requires invasive procedures for histological confirmation. The detection of tumor-specific genetic aberrations with utilization of cell free DNA (cfDNA) is a less invasive approach than traditional tissue biopsies; however, it has not been implemented into clinical routine. In this study, we investigated bile as a liquid biopsy source in pancreatobiliary cancers and compared its potential as cell-free DNA source to plasma. Blood (n = 37) and bile (n = 21) samples were collected from patients affected by pancreatic ductal adenocarcinoma (PDAC) and extrahepatic cholangiocarcinoma (CCA) or with non-malignant biliary obstructions (blood n = 16; bile n = 21). Panel-based next generation sequencing (NGS) and digital droplet PCR (ddPCR) were applied for tumor mutation profiling. NGS results from matched tumor tissues (n = 29) served as comparison. Sequencing of cfDNA from bile resulted in detection of 96.2% of the pathogenic tumor mutations found in matched tissue samples. On the other hand, only 31.6% of pathogenic tumor mutations found in tissue could be detected in plasma. In a direct comparison, only half of the mutations detected in bile cfDNA were concordantly detected in plasma from the same patients. Panel NGS and ddPCR displayed comparable sensitivity. In conclusion, bile is a suitable source of cfDNA for the diagnosis of pancreatobiliary cancer and performs more reliably than plasma. Although primary diagnosis still requires histologic confirmation, bile-derived cfDNA could offer an alternative if tissue sampling is not feasible and might allow less invasive disease monitoring.


2020 ◽  
Vol 12 ◽  
pp. 175883592092823 ◽  
Author(s):  
Damián García-Olmo ◽  
Susana Olmedillas-López ◽  
Delia Cortés-Guiral ◽  
Pedro Villarejo ◽  
Irene López Rojo ◽  
...  

Background: Acellular pseudomyxoma peritonei ( aPMP) is a rare peritoneal malignancy characterized by the accumulation of large amounts of mucin (lacking tumor cells) in the peritoneum. Many cases account for several kilograms of mucin to be screened by the pathologist. This is a comprehensive study of three patients with aPMP, whose tumors showed KRAS mutation, allowing for the tracking of this marker by liquid biopsy. Methods: Pre and post-surgery plasma, and mucin removed during cytoreductive surgery were collected from the patients. KRAS mutations were analyzed using droplet digital polymerase chain reaction (ddPCR). Mucin was injected in mice. KRAS and cytokine levels were measured in plasma of the mice using ddPCR and a magnetic bead-based assay. Mucin microbiome was analyzed by 16S rRNA sequencing. Results: KRAS mutations were detected in mucin cell-free DNA (cfDNA) from the three patients but not in the pre or post-surgery plasma. Electron microscopy detected microparticles (diameter <0.4 µm) in mucin. Mucin from one patient grew up inside the peritoneal cavity of mice and human KRAS was identified in mucin cfDNA, but not in plasma. All mucins showed the same bacterial profile. Cytokine levels were slightly altered in mice. Conclusions: The three aPMP patients included in this study shared some common aspects: the absence of tumor cells in mucin, the presence of KRAS mutated cfDNA in mucin, and the absence of this tumor-derived mutation in the bloodstream, providing additional information to the routine pathological examinations and suggesting that mucin cfDNA could potentially play a role in aPMP recurrence and prognosis.


2021 ◽  
Author(s):  
Thais Sabedot ◽  
Tathiane Malta ◽  
James Snyder ◽  
Kevin Nelson ◽  
Michael Wells ◽  
...  

Abstract Background The detection of somatic mutations in cell-free DNA (cfDNA) from liquid biopsy has emerged as a non-invasive tool to monitor the follow-up of cancer patients. However, the significance of cfDNA clinical utility remains uncertain in patients with brain tumors, primarily because of the limited sensitivity cfDNA has to detect real tumor-specific somatic mutations. This unresolved challenge has prevented accurate follow-up of glioma patients with non-invasive approaches. Methods Genome-wide DNA methylation profiling of tumor tissue and serum cell-free DNA of glioma patients. Results Here, we developed a non-invasive approach to profile the DNA methylation status in the serum of patients with gliomas and identified a cfDNA-derived methylation signature that is associated with the presence of gliomas and related immune features. By testing the signature in an independent discovery and validation cohorts, we developed and verified a score metric (the “glioma epigenetic liquid biopsy score” or GeLB) that optimally distinguished patients with or without glioma (sensitivity: 100%, specificity: 97.78%). Furthermore, we found that changes in GeLB score reflected clinicopathological changes during surveillance (e.g., progression, pseudoprogression or response to standard or experimental treatment). Conclusions Our results suggest that the GeLB score can be used as a complementary approach to diagnose and follow up patients with glioma.


Author(s):  
Suman Kumar Ray ◽  
Sukhes Mukherjee

: Cell-free DNA (cfDNA) is present in numerous body fluids in addition to initiates generally from blood cells. It is undoubtedly the utmost promising tool among all components of liquid biopsy. Liquid biopsy is a specialized method investigating the nonsolid biological tissue by revealing of circulating cells, cell free DNA etc. that enter body fluids. Since, cancer cells disengage from compact tumors circulate in peripheral blood, evaluating blood of cancer patients holds the opportunities for capture and molecular level analysis of various tumor-derived constituents. Cell free DNA samples can deliver a significant perceptions into oncology, for instance tumor heterogeneity, instantaneous tumor development, response to therapy and treatment, comprising immunotherapy and mechanisms of cancer metastasis. Malignant growth at any phase can outhouse tumor cells in addition to fragments of neoplasticity causing DNA into circulatory system giving noble sign of mutation in the tumor at sampling time. Liquid biopsy distinguishes diverse blood based evolving biomarkers comprising circulating tumor cells (CTCs), circulating tumor DNA (ctDNA) or cfDNA, circulating RNA (cfRNA) and exosomes. Cell free DNA are little DNA fragments found circulating in plasma or serum, just as other fluids present in our body. Cell free DNA involves primarily double stranded nuclear DNA and mitochondrial DNA, present both on a surface level and in the lumen of vesicles. The probable origins of the tumor-inferred portion of cfDNA are apoptosis or tumor necrosis, lysis of CTCs or release of DNA from the tumor cells into circulation. The evolution of innovations, refinement and improvement in therapeutics for determination of cfDNA fragment size and its distribution provide significant information related with pathological conditions of the cell, thus emerging as promising indicator for clinical output in medical biotechnology.


2021 ◽  
Vol 67 (4) ◽  
pp. 576-578
Author(s):  
Margaritis Avgeris ◽  
Antonios Marmarinos ◽  
Dimitrios Gourgiotis ◽  
Andreas Scorilas
Keyword(s):  

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