Expression of VHL tumor suppressor mRNA and miR-92a in papillary thyroid carcinoma and their correlation with clinical and pathological parameters

AbstractA growing body of evidence suggests a role of the von Hippel –Lindau (VHL) tumor suppressor gene in the progression of papillary thyroid carcinoma (PTC). Our previous study ofVHL in PTCs showed that lowerVHL expression was associated with aggressive tumor features, but we found no evidence forVHL downregulation through common genetic or epigenetic modifications. Several studies pointed to a role of microRNA-92a (miR-92a) in the regulation ofVHL expression in different cancers. In the present study, we examined the expression levels ofVHL mRNA and miR-92a in 42 pairs of PTCs and matched non-tumor thyroid tissues by means of quantitative RT-PCR. We explored the correlation between them and their association with clinicopathological parameters. The results revealed that bothVHL and miR-92a were either up- or downregulated in PTCs compared to corresponding non-tumor tissues. On univariate analysis, lowerVHL levels were significantly associated with extrathyroid spread (P = 0.022) and capsular invasion (P = 0.032). Multivariate analysis confirmed the association of lowVHL with extrathyroid spread (OR 0.246, 95% CI 0.069 –0.872,P = 0.038). Higher miR-92a among PTC tissues associated with the presence of nodal metastases (univariate analysis:P = 0.012; multivariate: OR 4.703, 95% CI 1.109–19.938,P = 0.036). A negative correlation betweenVHL and miR-92a was observed in a subgroup of PTCs having vascular invasion (P = 0.033,r = − 0.673). The data here re...
Source: Medical Oncology - Category: Cancer & Oncology Source Type: research