Figure 1

RNA integrity from laser capture-microdissected malignant epitheluim and surrounding stromal in breast cancer tumor sections. Cresyl violet staining of a representative triple-negative breast tumor section (A) with defined (B) and dissected (C) cancer cells. Electropherogram depicting RNA from microdissected cancer (D) and stromal breast tumor (E) cells in comparison with RNA from total tissue section (F). RNA length is indicated on the x-axis, and the y-axis corresponds to the fluorescence units (FU). RNA integrity number (RIN) values are calculated according to a standardized algorithm by using various features correlated to RNA integrity. nt, nucleotides.