Optimization of storage conditions for formalin-fixed paraffin-embedded tissue sections to be used in molecular testing.

e23137Background: FFPE tissue sections are routinely stored at ambient temperature in pathology departments for histology staining, immunohistochemistry, and in situ hybridization. These specimens are also utilized for mutation detection and gene expression tests. The RNA degradation and modification during formalin fixation, and additional deterioration that may occur during storage, diminish the utility of these valuable samples for quantitative molecular analysis. This study was designed to determine the impact of storage conditions and times on the integrity of FFPE samples by analyzing the RNA extracted from well-characterized paraffin-embedded cell pellets. Methods: H460, a large cell lung carcinoma cell line, was cultured. Cells were then harvested, fixed, and embedded in paraffin. Storage at 35°C, ambient temperature (20–25°C), and 4°C was tested for a period of 6 months. RNA was evaluated for total yield, intactness, and functional RT-qPCR performance. Six replicate sections for each condition we...