Intratumor heterogeneity of gene expression profiles in early stage non-small cell lung cancer (NSCLC)

Gene expression profiling of NSCLC tissues let to the establishment of several prognostic, predictive gene signatures with little overlap. To study factors introducing variability into gene expression microarray studies we compared interpatient (patient-to-patient) and intrapatient (tumor sub-sample) variations in gene expression profiles in stage I and II NSCLC tissues. We identified 128 probe sets which showed variable intratumoral expression Four different sites (A,B,C,D) of individual primary tumors and matched distant normal lung tissue (N) from 20 patients were used to establish gene expression patterns captured by Affymetrix HG-U133 Plus 2.0 arrays (n = 100).