nERGs and tERGs ranked according to their expression stability, as calculated by the two programs, geNorm and NormFinder, based on qRT-PCR data in each tissue type of FFPE tissues.

*Gene expression stability S by NormFinder was calculated as an estimate of the combined intra and intergroup variation between normal and tumor tissues. For ovary tissues (n = 33), 10 normal and 23 tumor tissues were included and 17 stomach tissues, including normal (n = 8) and tumor (n = 9) tissues, were used in the analysis.Low average expression stability M and stability value S indicate the high expression stability.