Circulating long non-coding RNAs in plasma of patients with gastric cancer.

BACKGROUND: We examined the levels of long non-coding RNAs (lncRNAs) in the plasma of patients with gastric cancer to assess their clinical significance for diseases diagnosing and monitoring.

MATERIALS AND METHODS: We investigated the stability of plasma lncRNAs, and then confirmed the appropriateness of the lncRNA assay with a pre-amplification method. The levels of plasma lncRNAs, H19, HOX antisense intergenic RNA (HOTAIR), and metastasis associated lung adenocarcinoma transcript-1 (MALAT1), were then analyzed in patients with gastric cancer (GC) and healthy controls.

RESULTS: Plasma lncRNAs exhibited minimal gradual instability only under several severe conditions. Analysis showed that samples with pre-amplification had a higher level of linearity in the reverse transcription polymerase chain reaction (RT-PCR) assay than those without pre-amplification. Plasma H19 levels were significantly higher in patients than in healthy controls. Plasma H19 levels were significantly reduced in postoperative samples.

CONCLUSION: Circulating lncRNAs can be detectable in plasma, and the detection of circulating lncRNAs may provide new complementary tumor markers for gastric cancer.