scholarly journals Analysis of cancer-related mutations in extracellular vesicles RNA by Droplet Digital™ PCR

BioTechniques ◽  
2020 ◽  
Vol 69 (2) ◽  
pp. 99-107
Author(s):  
Soo Ann Yap ◽  
Agnieszka Münster-Wandowski ◽  
Anika Nonnenmacher ◽  
Ulrich Keilholz ◽  
Sandra Liebs
Keyword(s):  
Colorectal Cancer ◽  
Tumor Progression ◽  
Extracellular Vesicles ◽  
Liquid Biopsy ◽  
Mek Inhibitor ◽  
Diagnostic Information ◽  
Braf V600e ◽  
Plasma Samples ◽  
Differential Centrifugation ◽  
Potential Biomarkers

Extracellular vesicles (EVs) are taking their place as potential biomarkers in the field of liquid biopsy. In this study, EVs were isolated from plasma samples of 31 patients with colorectal cancer and melanoma via differential centrifugation and Droplet Digital™ PCR (Bio-Rad, CA, USA) was used to profile BRAF V600E/K, KRAS G12A/C/D/V and KRAS G13D mutations from EV-derived cDNA. The concordance rates with corresponding tissue were 54% and 44% in the colorectal cancer and melanoma cohort, respectively. Two patients displayed mutations in EVs not previously detected in tissue as evidence for emerging molecular resistance to anti-EGFR and BRAF/MEK inhibitor therapy prior to radiological evidence of tumor progression. We concluded that EV-derived nucleic acids may provide clinically relevant diagnostic information and mirror evolution of the disease.

scholarly journals Plasma extracellular vesicles detected by Single Molecule array technology as a liquid biopsy for colorectal cancer

2020 ◽  
Vol 9 (1) ◽  
pp. 1809765 ◽  
Author(s):  
Ping Wei ◽  
Fei Wu ◽  
Bin Kang ◽  
Xiaohua Sun ◽  
Fabienne Heskia ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Extracellular Vesicles ◽  
Single Molecule ◽  
Liquid Biopsy ◽  
Array Technology

cfDNA for accurate determination of RAS and BRAF mutations using OncoBEAM liquid biopsy in metastatic colorectal cancer patients: Results of the real-world multicentric ColoBEAM study.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 3542-3542 ◽  
Author(s):  
Alexandre Harle ◽  
Celine Gavoille ◽  
Olivier Bouche ◽  
Meher Ben Abdelghani ◽  
Jérôme Edouard Plaza ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Liver Metastasis ◽  
Metastatic Colorectal Cancer ◽  
Liquid Biopsy ◽  
Accurate Determination ◽  
Braf V600e ◽  
Molecular Testing ◽  
Braf Mutations ◽  
Blood Samples

3542 Background: Determination of KRAS, NRAS ( RAS) and BRAF mutations is a standard of care for the management of patients with metastatic colorectal cancer (mCRC). RAS mutations are well characterized resistance biomarkers to anti-EGFR antibodies and BRAF V600 mutations indicate poor prognosis. Tissue biopsy has traditionally been used to determine RAS and BRAF status, but liquid biopsy analysis of circulating tumor DNA (ctDNA) has demonstrated utility as a less invasive tool to expedite molecular testing results to the clinic. The ColoBEAM study reports the performance of plasma mutation testing in a real-life prospective series of 278 patients across 8 centers. Methods: Plasma derived ctDNA was prepared from 20mL blood samples prospectively collected from mCRC patients who had not received chemotherapy in the prior 15 days. ctDNA was centrally assessed using OncoBEAM and results compared to those obtained by routine analysis of tissue. Both tissue and blood samples with discrepant RAS results were blindly reassessed with OncoBEAM. Results: Of 278 patients enrolled, 202 blood samples were available for OncoBEAM testing. RAS and BRAF V600E mutations were detected in tissue in 132/202 (65.4%) and 4/198 (2.0%) patients, respectively. Analysis of the first ctDNA sample as compared to tissue DNA resulted in a kappa coefficient (κ) of 0.52 [0.41 – 0.63] and accuracy of 75.2% (65.1% sensitivity; 94.3% specificity). OncoBEAM testing of a second sample resulted (κ) of 0.66 [0.56 - 0.76] and accuracy of 83.2% (77.3% sensitivity; 94.3% specificity). Of the 4 samples with a BRAF V600E mutation in tumor tissue 2 were detected in blood. In the subgroup of patients with liver metastasis (n=136), accuracy was 88.2% (87.4% sensitivity; 90.2% specificity) for RAS and BRAF status with (κ) of 0.73 [0.61 – 0.86]. In a subgroup of chemotherapy naïve patients with liver metastasis (n=49), accuracy was 91.8% (93.3% sensitivity; 89.5% specificity) for RAS and BRAF status with (κ) of 0.83 [0.67 – 0.99]. Conclusions: The results of the ColoBEAM study confirm plasma ctDNA as a credible surrogate marker to tissue DNA for RAS and BRAF status assessment and may be incorporated as a first-line theragnostic assessment. New testing on a second sample for wild-type status demonstrated 91.8% concordance between blood and tissue. Clinical trial information: NCT02751177.

scholarly journals Alisertib exerts KRAS allele specific anticancer effects in colorectal cancer

2020 ◽  
Author(s):  
Baojun Ren ◽  
Zhuowei Gao ◽  
Kehong Zheng ◽  
Yong Yang ◽  
Pengfei Su ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Signaling Pathway ◽  
Active Form ◽  
Mek Inhibitor ◽  
Braf V600e ◽  
Ras Signaling ◽  
Kras Mutations ◽  
Ras Signaling Pathway ◽  
Specific Manner ◽  
Allele Specific

AbstractColorectal cancer (CRC) is a common cancer causing substantial mortality and morbidity worldwide. Oncogene RAS mutations occur notably in ∼45% of CRCs, associated with a poor prognosis. KRAS is subject to multiple tiers of regulation, including kinase. Aurora kinases has been implicated in many types of tumor onsets and progression, making them as a promising therapeutic targets. Alisertib (ALS), selectively inhibits Aurora kinase A (AURKA) and exerts potent anticancer activities in vitro and in vivo studies, but the latent anticancer effect of ALS on CRC remains unclear in the context of different KRAS mutations. This study aimed to assess the effects of ALS on RAS signaling pathway in a panel of CRC lines expressing different KRAS alleles, including Caco-2 (KRAS WT), Colo-678 (KRAS G12D), SK-CO-1 (KRAS G12V), HCT116 (KRAS G13D), CCCL-18 (KRAS A146T), and HT29 (BRAF V600E). The results showed that ALS modulated the active form of KRAS in a RAS allele specific manner across the panel of CRC lines; ALS differentially regulated RAS signal via PI3K/Akt and MAPK pathways; and ALS induced apoptosis and autophagy in a RAS allele specific manner. Of note, in combination of ALS and MEK inhibitor, selumetinib, enhanced ALS regulatory effects in CRC lines in a RAS allele specific manner on apoptosis, autophagy, and cell growth. Taken together, this study suggests that ALS differentially regulates RAS signaling pathway and manipulates cell apoptosis and autophagy in RAS allele specific manner. The combinatorial approach of ALS and MEK inhibitor may represent a new therapeutic strategy for precision therapy of CRC in a RAS allele manner.

Abstract 269: Small non-coding RNA profiling in stool and plasma samples to explore potential biomarkers for colorectal cancer diagnosis

2020 ◽  
Author(s):  
Antonio Francavilla ◽  
Sonia Tarallo ◽  
Giulio Ferrero ◽  
Francesca Cordero ◽  
Gaetano Gallo ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cancer Diagnosis ◽  
Plasma Samples ◽  
Rna Profiling ◽  
Non Coding Rna ◽  
Potential Biomarkers
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