Sensitivity of RT-qPCR using TLDA platform. Expression levels of 93 candidate genes were analyzed using cDNA generated from total RNA isolated from peripheral blood samples from a healthy female donor and the same blood spiked with 4, 40 and 400 T47-D tumor cells after cell enrichment. RNA was pre-amplified using the TargetAmp™1-Round aRNA Amplification Kit. Average Ct values obtained from RT-qPCR amplification of CCNE2, DKFZp762E1312, EMP2, MAL2, PPIC, and SLC6A8 transcripts using the TLDA format are shown. MAL2 and CCNE2 gene expression was below the detection limit of RT-qPCR in the unspiked blood. The detection sensitivity of the respective marker gene was estimated to be 40 and 400 tumor cells per 15 ml whole blood.
Obermayr et al. BMC Cancer 2010 10:666 doi:10.1186/1471-2407-10-666