Long non-coding (lnc)RNA PAPAS overexpression inhibits tumor growth in papillary thyroid carcinoma by downregulating lncRNA HOTTIP

The long non-coding (lnc)RNA pre-ribosomal RNA antisense transcripts (PAPAS) can repress ribosomal RNA synthesis, although its role in human disease is currently unknown. The present study aimed to investigate the function of PAPAS in papillary thyroid carcinoma (PTC). PAPAS was downregulated, while the lncRNA HOXA transcript at the distal tip (HOTTIP) was upregulated in patients with PTC. PAPAS and HOTTIP were inversely associated in PTC. PAPAS overexpression led to the downregulation of HOTTIP in PTC cells, while PAPAS expression was not significantly affected by HOTTIP overexpression, suggesting that PAPAS was upstream of HOTTIP. PAPAS expression level decreased, while HOTTIP expression level increased with the increase of clinical staging. PAPAS overexpression led to the inhibition of cell proliferation, while HOTTIP overexpression increased proliferation of PTC cells, and HOTTIP overexpression decreased the effects of PAPAS overexpression. lncRNA PAPAS overexpression may inhibit tumor growth in papillary thyroid carcinoma by downregulating lncRNA HOTTIP.