Circular RNA could be new biomarker for gastric cancer

Last Updated: 2017-02-01

By David Douglas

NEW YORK (Reuters Health) - Circular RNA 0000096 (hsa_circ_0000096) levels are significantly downregulated in gastric cancer, suggesting a role in detection according to Chinese researchers.

As Dr. Junming Guo told Reuters Health by email, "We found that hsa_circ_0000096 was of low expression in gastric cancer tissues and gastric cancer cell lines. Thus it may be a potential novel biomarker for the diagnosis of gastric cancer."

In a paper online January 12 in the British Journal of Cancer, Dr. Guo of Ningbo University School of Medicine and colleagues note that circular RNAs are more stable in plasma and gastric juice than are microRNAs and long non-coding RNAs.

"This remarkable feature," they add, "makes them an ideal choice for use as molecular markers of gastric cancer. However, the biological functions of circRNAs in human diseases, especially in cancer, are unclear."

To investigate further, they examined hsa_circ_0000096 levels in 101 paired gastric cancer tissues and adjacent non-tumorous tissues and normal gastric epithelial cells from patients with gastric cancer.

Hsa_circ_0000096 was found to be significantly downregulated in gastric cancer tissues and gastric cancer cell lines compared with paired adjacent non-tumorous tissues and normal gastric epithelial cells.

Moreover, say the researchers, "knockdown of hsa_circ_0000096 significantly inhibited cell proliferation and migration in vitro and in vivo." Protein levels of CDK6, cyclin D1, MMP-2 and MMP-9 showed corresponding changes.

The reduction in migration of human gastric cancer cell line BGC-823 was the most pronounced, followed by MGC-803 cells.

The researchers found slower tumor growth after knockdown of hsa_circ_0000096 in xenograft nude mouse models. Protein levels of CDK6, cyclin D1, MMP-2, MMP-9, Ki67 and VEGF showed a dose-dependent decrease.

Thus, the team points out, "hsa_circ_0000096 affected gastric cancer cell growth and migration by interfering with the expression of cell cycle-associated and migration-associated proteins."

SOURCE: http://bit.ly/2jWrGXI

Br J Cancer 2017.