Abstract: Objective To explore the effects of long non-coding RNA (lncRNA) -H19 on the proliferation, invasion and cell cycle of thyroid cancer cells. Methods The expression of lncRNA-H19 in cancer tissues, para-cancerous tissues, normal human thyroid epithelial cells (TEC) and thyroid cancer cells (KAT18, FTC133, BCPAP, TPC-1) were detected. The effects of silencing lncRNA-H19 on cell proliferation, invasion and cell cycle were detected. Results The lncRNA-H19 was highly expressed in thyroid cancer tissues and cell lines. The expression levels of lncRNA-H19 among thyroid cancer patients with different tumor sizes, N staging and TNM staging were significantly different (P< 0. 05). After silencing lncRNA-H19, the cell proliferation rate, clone formation rate, number of migrating cells and number of microvessel formation at 48 h and 72 h were significantly decreased (P< 0. 05), the expression levels of Ki67, PCNA, N-cadherin, Fibronectin, VEGF, MMP-9, MMP-14, cyclin A, CDK2, CDK4 and cyclin D1 proteins were significantly decreased (P< 0. 05), and the expression level of E-cadherin protein was significantly increased (P< 0. 05). Conclusion Silencing lncRNA-H19 could regulate the proliferation, invasion and cell cycle of FTC133 by regulating the expression of cell cycle related proteins.

Key words: thyroid cancer, long non-coding RNA, lncRNA-H19, cell proliferation, cell invasion, cell cycle