Exosomal miRNA Analysis in Non-small Cell Lung Cancer (NSCLC) Patients' Plasma Through qPCR: A Feasible Liquid Biopsy Tool.
The discovery of alterations in the EGFR and ALK genes, amongst others, in NSCLC has driven the development of targeted-drug therapy using selective tyrosine kinase inhibitors (TKIs). To optimize the use of these TKIs, the discovery of new biomarkers for early detection and disease progression is mandatory. These plasma-isolated exosomes can be used as a non-invasive and repeatable way for the detection and follow-up of these biomarkers. One ml of plasma from 12 NSCLC patients, with different mutations and treatments (and 6 healthy donors as controls), were used as exosome sources. After RNAse treatment, in order to degrade circulating miRNAs, the exosomes were isolated with a commercial kit and resuspended in specific buffers for further analysis. The exosomes were characterized by western blotting for ALIX and TSG101 and by transmission electron microscopy (TEM) analysis, the standard techniques to obtain biochemical and dimensional data of these nanovesicles. Total RNA extraction was performed with a high yield commercial kit. Due to the limited miRNA-content in exosomes, we decided to perform retro-transcription PCR using an individual assay for each selected miRNA. A panel of miRNAs (30b, 30c, 103, 122, 195, 203, 221, 222), all correlated with NSCLC disease, were analyzed taking advantage of the remarkable sensitivity and specificity of Real-Time PCR analysis; mir-1228-3p was used as endogenous control and data were processed according to the formula 2(-) (ΔΔct) (13). Control values were used as baseline and results are shown in logarithmic scale.
Department of Biopathology and Medical Biotechnology, Section of Biology and Genetics, University of Palermo; Phase I-Early Clinical Trials Unit, Oncology Department, Antwerp University Hospital (UZA).
Marco
M
Giallombardo
Phase I-Early Clinical Trials Unit, Oncology Department, Antwerp University Hospital (UZA); Center for Oncological Research (CORE), Antwerp University.
Jorge
J
Chacártegui Borrás
Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo.
Marta
M
Castiglia
Center for Oncological Research (CORE), Antwerp University.
Nele
N
Van Der Steen
Flemish Institute for Technological Research (VITO); CORE, Campus Groenenborger, Antwerp University.
Inge
I
Mertens
Molecular Pathology, Pathology Department, Antwerp University Hospital (UZA); Center for Oncological Research (CORE), Antwerp University.
Patrick
P
Pauwels
Oncology Department, Antwerp University Hospital (UZA); Center for Oncological Research (CORE), Antwerp University.
Marc
M
Peeters
Phase I-Early Clinical Trials Unit, Oncology Department, Antwerp University Hospital (UZA); Center for Oncological Research (CORE), Antwerp University; Christian.Rolfo@uza.be.
Christian
C
Rolfo
D014408:Biomarkers, Tumor / Q000032:analysis / Q000097:blood / Q000235:genetics; D001706:Biopsy / Q000379:methods*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood / Q000235:genetics* / Q000473:pathology; D016022:Case-Control Studies; D019286:Endopeptidase K; D055354:Exosomes / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood / Q000235:genetics* / Q000473:pathology; D035683:MicroRNAs / Q000032:analysis / Q000097:blood* / Q000235:genetics; D011933:Reagent Kits, Diagnostic; D060888:Real-Time Polymerase Chain Reaction; D012260:Ribonucleases
D014408:Biomarkers, Tumor; D035683:MicroRNAs; D011933:Reagent Kits, Diagnostic; D012260:Ribonucleases; D019286:Endopeptidase K