Expression of Rho GDP dissociation inhibitor alpha in papillary thyroid carcinoma and its clinical significance

Abstract

Objective To observe the level of Rho GDP dissociation inhibitor (GDI) alpha (RhoGDIa) expression in papillary thyroid carcinoma (PTC) and explore its clinical significance. Methods The levels of RhoGDIa and microRNA (miRNA, miR)-151-5p expression in 200 cases of PTC tissues and paired normal tissues were detected by real-time quantitative polymerase chain reaction (Real-time PCR), respectively. The relationship between RhoGDIa expression and the clinicopathological features in PTC patients, and between RhoGDIa expression and miR-151-5p levels in PTC tissues was investigated. Results As compared with normal tissues adjacent to cancer, the expression of RhoGDIa mRNA was decreased in 76.5% (153/200) PTC tissues and that of miR-151-5p was increased in 72.5% (145/200) PTC tissues, respectively. The correlation analysis showed that there was a significantly negative correlation between the miR-151-5p level and the expression of RhoGDIa mRNA in PTC tissues (r=-0.925, P=0.000). As compared with PTC without lymph node metastasis, the miR-151-5p level was significantly up-regulated and the expression of RhoGDIa protein was significantly down-regulated in those PTC with lymph node metastasis, and the expression abundance of miR-151-5p was negatively correlated with the level of RhoGDIa protein. The low expression of RhoGDIa mRNA was significantly correlated with gender (P=0.000), number of lesions (P=0.004), local invasion (P=0.002), lymph node metastasis (P=0.000) and clinical stage (P=0.000) in PTC patients. Conclusion RhoGDIa was down-regulated in PTC tissues and closely related to tumor progression, and its expression may be negatively regulated by miR-151-5p. Key words: Papillary thyroid carcinoma; Rho GDP dissociation inhibitor alpha; MicroRNA-151-5p; Lymph node metastasis