RESUMEN
INTRODUCTION: Papillary thyroid cancer (PTC) is a common malignant tumour in the endocrine system with increasing incidence. LncRNA HCG22 (HCG22) was noticed to be dysregulated in PTC, but its specific function and mechanism remain unknown. The function of HCG22 and its underlying molecular mechanism was investigated to evaluate its potential as a biomarker for PTC. MATERIAL AND METHODS: The expression of HCG22 was detected in PTC cells (TPC-1, SNU790, GLAG-66, and BCPAP) and normal thyroid cells (Nthy-ori) using real time quantative polymerase chain reaction (RT-qPCR). HCG22 and miR-425-5p were regulated by cell transfection. The cell proliferation and metastasis were assessed by CCK8 and Transwell assay. RESULTS: HCG22 was upregulated in PTC cells, of which the knockdown suppressed the proliferation, migration, and invasion of PTC cells. miR-425-5p was downregulated in PTC cells, which was negatively regulated by HCG22. Silencing miR-425-5p could reverse the inhibitory effect of HCG22 knockdown on the cellular processes of PTC. CONCLUSIONS: HCG22 served as a tumour promoter in PTC cells, which regulated cell proliferation and metastasis via negatively regulating miR-425-5p.