Graphical scheme of the experimental plan. Following a step down strategy, six genes from initially 27.686 genes were identified as new gene markers for the RT-qPCR based detection of circulating tumor cells (CTC). In microarray analysis, we compared expression profiles of PBMC isolated by Ficoll gradient centrifugation from healthy individuals and various established cancer cell lines. In microarray validation, we compared expression profiles of PBMC isolated by Oncoquick from healthy individuals and cell lines. cDNA was amplified according to a published protocol . For the experimental analysis of patients samples, we used Oncoquick only. cDNA was amplified using the TargetAmp™1-Round aRNA Amplification Kit.
Obermayr et al. BMC Cancer 2010 10:666 doi:10.1186/1471-2407-10-666