Effects of long non-coding RNA H19 and microRNA let7a expression on thyroid cancer prognosis

Abstract

This study aims to explore the effects of long non-coding RNA H19 (lncRNA H19) and microRNA let7a (miRNA let7a) expression on the prognosis of thyroid cancer (TC). This may aid in the discovery of more effective treatment and prognosis approaches for TC. Between January 2008 and January 2011, 131 TC tissues and adjacent tissues were obtained from TC patients. An additional 122 normal thyroid tissues were also collected as normal controls from patients with benign thyroid lesions. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect lncRNA H19 and miRNA let7a mRNA expression. Five-year follow-ups were conducted. A Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic values of lncRNA H19 and miRNA let7a in TC. The Kaplan-Meier method was applied to analyze the 5-year survival rate of TC patients. Univariate and multivariate factor analyses were employed to analyze the prognostic factors of TC. The lncRNA H19 mRNA expression was higher while the miRNA let7a mRNA expression was lower in TC tissues than, in the normal thyroid tissues and adjacent tissues. The area under the ROC curve (AUC) of lncRNA H19 and miRNA let7a were 0.801 and 0.116, with sensitivity at 72.5% and 84%, as well as specificity 75.4% and 77%, respectively. In TC patients with tumor diameters≥1.0cm, lncRNA H19 mRNA expression was elevated, but miRNA let7a mRNA expression was reduced. This was also evident in TC patients with TNM stages III+IV and those with lymph node metastasis. TC patients with a lower 5-year survival rate showed upregulated levels of lncRNA H19 expression and, downregulated levels of miRNA let7a expression. LncRNA H19 and miRNA let7a expression, tumor diameter, TNM stage and lymph node metastasis were independent prognostic factors of TC. This study demonstrated that increased lncRNA H19 and decreased miRNA let7a expression levels are associated with poor prognosis in TC patients. An inverse relationship between lncRNA H19 and miRNA let7a expression levels was exhibited.

Keywords: Long noncoding RNA H19; MicroRNA Let7a; Prognosis; Thyroid cancer.