Our results show the potential importance of miR-221, miR-222, and miR-146b in determining the aggressive properties of PTCs and highlight the need to identify the gene targets of these miRNAs.
Context: Recent studies suggest that miR-146b deregulation in papillary thyroid carcinoma (PTC) was associated with advanced tumor characteristics. However, the influence of miR-146b expression on the prognosis of PTC remains unknown. We sought to correlate tumor expression levels of miR-146b with the prognosis of a previously reported PTC cohort and reveal the underlying mechanisms via a PTC cell line model.
Methodology:Expression levels of miR-146b were assessed via quantitative real-time PCR in 71 cases of PTC with distinct clinico-pathogenetic characteristics. All patients were classified into the disease-free or active disease group, based on their medical records at the end of the follow-up period. In vitro gain-of-function experiments were performed in a BCPAP human papillary thyroid cancer cell line model, which harbored the homozygous mutation of BRAF. BCPAP cells were transfected with a mimic-miR-146b and nonspecific microRNA (miRNA) control to determine whether miR-146b overexpression promotes cell migration and invasion. Proliferation assay, colony formation assay, and chemotherapy-induced apoptosis were also determined.
Results:Multivariate logistic regression analysis demonstrated advanced tumor stage, presence of cervical lymph node metastasis, and miR-146b expression were independent risk factors for poor prognosis in PTC. Patients with higher miR-146b expression levels had significantly poorer overall survival compared with those with lower miR-146b levels. The associated hazard ratio was 3.92 (95% confidence interval, 1.73-8.86, log-rank P Ͻ .05). Overexpression of miR-146b significantly increased cell migration and invasiveness. Furthermore, miR-146b also increased resistance to chemotherapy-induced apoptosis.
Conclusions:Our results suggest that miR-146b is a novel prognostic factor of PTC. Furthermore, in vitro functional studies provided the mechanistic explanation for miR-146b in tumor aggressiveness. These results enhance understanding of the molecular mechanisms involved in tumor aggressiveness in PTC, provide new prognostic biomarkers, and ultimately offer new leads for developing therapies for PTC. (J Clin Endocrinol Metab 98: E196 -E205, 2013)
SummaryBackground The aim of this study was to identify the prognostic factors of long-term survival and optimal therapeutic protocol for patients with distant metastasis secondary to differentiated thyroid carcinoma (DTC). Methods A retrospective review of 1665 patients with DTC treated at a regional tertiary hospital in Taiwan between 1986 and 2010 was performed. Among them, 207 patients were found to have distant metastasis. For a long-term outcome survey, 126 patients that had received at least 5 years (mean 9AE6 ± 5AE2 years) of follow-up after the diagnosis of distant metastasis were analysed for this study. Prognostic factor analysis included age, sex, histology, disease stage, type of surgical procedure, site of metastatic foci, 131 I
Papillary thyroid cancer (PTC) is the most common tumor subtype of thyroid cancer. However, not all PTCs are responsive to current surgical and radioiodine treatment. The well-established clinical prognostic factors include tumor size, lymph node/distal metastasis, and extrathyroidal invasion. The RET/PTC-RAS-BRAF linear molecular signaling cascade is known to mediate PTC pathogenesis. However, whether presence of BRAF mutation, the most common genetic alteration in PTC, can affect PTC behavior and prognosis is controversial. MicroRNAs (miRNAs) have been labeled as promising molecular prognostic markers in several tumor types. Our recent studies demonstrated that microRNA-146b (miR-146b) deregulation is associated with PTC aggressiveness and prognosis. Here we summarize the current knowledge related to the functional roles, regulated target genes, and clinical applications of miR-146b in PTC and discuss how these studies provide insights into the key role of miR-146b as an oncogenic regulator promoting cellular transformation as well as a prognosis marker for tumor recurrence in PTC. In conjunction with the current perspectives on miRNAs in a wide variety of human cancers, this review will hopefully translate these updated findings on miR-146b into more comprehensive diagnostic or prognostic information regarding treatment in PTC patients before surgical intervention and follow up strategies.
A 12-week TCC exercise programme decreases HbA1c levels along with an increase in the Th1 reaction. A combination of TCC with medication may provide an even better improvement in both metabolism and immunity of patients with type 2 DM.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.