Figure 5

Origin of circulating lncRNAs. (A) Quantitative real time polymerase chain reaction (qPCR) was used to measure ESCC-related lncRNAs expression in five esophageal cells. GAPDH was used as a normalization control. (B) ESCC-related lncRNAs could be secreted into the cell culture medium. Data presented as relative lncRNAs fold change. (C) ESCC-related lncRNAs could enter into the circulation of xenograft-bearing mice. (D) Spearman’s rank correlation scatter plot of ESCC-related lncRNAs levels in tumor samples and plasma. Data were presented as △Ct values normalized to GAPDH. (E) ESCC-related lncRNAs expressions were significantly declined in post-operative samples compared with that in pre-operative samples. (F) Effect of delayed blood centrifugation on plasma ESCC-related lncRNAs expressions. At room temperature, ESCC-related lncRNAs levels of unfiltered plasma was slightly increased from 0 h to 6 h, but then significantly decreased at 24 h when compared to 6 h. *p < 0.05.