title: Detection and recovery of circulating colon cancer cells using a dielectrophoresis-based device: KRAS mutation status in pure CTCs.
abstract: The characterization of circulating tumor cells (CTCs) could substantially improve the management of cancer patients. However, their study is still a matter of debate, often due to lymphocyte contamination. In the present paper, an investigation of CTCs was carried out for the first time using DEPArray, a dielectrophoresis-based platform able to detect and sort pure CTCs. Analyses were conducted on peripheral blood (PB) samples from patients with metastatic colon cancer. After 100% pure cell recovery and whole genome amplification, KRAS gene mutation of CTCs was screened and compared to gene status in the primary tumor tissue. CTCs were found in 21 colon cancer patients (52.5%), with more than three tumor cells per 7.5 ml. KRAS gene mutation analysis, showed a mutational concordance between CTCs and primary tumor in 50% of matched cases. The present study demonstrates for the first time the feasibility of analyzing at the molecular level pure CTCs avoiding lymphocyte contamination using an innovative instrumentation, and a KRAS discordance between CTCs and primary tissue. Our results present dielectrophoresis-based procedures as a new standard in single cell analysis and recovery and invite careful reflection on the value of CTCs characterization.
authors: Biosciences Laboratory, IRCCS Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), Meldola, Italy. francesco.fabbri@irst.emr.it
authors: Francesco
authors: F
authors: Fabbri
authors: Silvia
authors: S
authors: Carloni
authors: Wainer
authors: W
authors: Zoli
authors: Paola
authors: P
authors: Ulivi
authors: Giulia
authors: G
authors: Gallerani
authors: Pietro
authors: P
authors: Fici
authors: Elisa
authors: E
authors: Chiadini
authors: Alessandro
authors: A
authors: Passardi
authors: Giovanni L
authors: GL
authors: Frassineti
authors: Angela
authors: A
authors: Ragazzini
authors: Dino
authors: D
authors: Amadori
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D002469:Cell Separation / Q000379:methods*; D002499:Centrifugation, Density Gradient; D003110:Colonic Neoplasms / Q000473:pathology*; D004586:Electrophoresis; D005260:Female; D006801:Humans; D007633:Keratins / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D009360:Neoplastic Cells, Circulating / Q000378:metabolism*; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D007633:Keratins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins