Recently, it has been reported that circRNA is associated with tumor development, migration, and invasion, for example, circRNA_001569 targeting miR‐145 in the proliferation and invasion of colorectal cancer.6 Circular RNA CCDC66 promotes colon cancer growth and metastasis.7 Overexpression of circRNA_100876 in non–small‐cell lung cancer and its prognostic value.18 Notably, circRNA has been found to play an important role in GC development, migration, and invasion. This evidence concerns the gene CCDC66 and gastric cancer.