Assessment of RNA integrity in frozen sections of mouse SCCVII tumor tissue. The Agilent BioAnalyzer system determined that the RNA from two-round amplification of endothelial and epithelial cell samples had comparable concentration of 1278.5 ng/μl. The spectra clearly indicated the presence of a marker peak and a broad hump in the electropherogram confirming good RNA quality. Further mRNA analysis demonstrated a high quality starting sample of total RNA by the 260/280 ratio for the five endothelial and epithelial cell samples. Moreover, the RNA quality and concentration was comparable to that of the control sample.