Up-regulation of urinary-type plasminogen activator correlates with high-risk papillary thyroid carcinoma with BRAF(V600E) mutation and its possible molecular mechanism

NF-κB signaling activation and roles in thyroid cancers: implication of MAP3K14/NIK

Among follicular-derived thyroid cancers (TC), those with aggressive behavior and resistance to current treatments display poor prognosis. NF-κB signaling pathways are involved in tumor progression of various cancers. Here, we finely characterize the NF-κB pathways and their involvement in TC. By using immunoblot and gel shift assays, we demonstrated that both classical and alternative NF-κB pathways are activated in ten TC-derived cell lines, leading to activated RelA/p50 and RelB/p50 NF-κB dimers. By analyzing the RNAseq data of the large papillary thyroid carcinoma (PTC) cohort from The Cancer Genome Atlas (TCGA) project, we identified a tumor progression-related NF-κB signature in BRAFV600E mutated-PTCs. That corroborated with the role of RelA and RelB in cell migration and invasion processes that we demonstrated specifically in BRAFV600E mutated-cell lines, together with their role in the control of expression of genes implicated in invasiveness (MMP1, PLAU, LCN2 and LGALS3). We also identified NF-κB-inducing kinase (NIK) as a novel actor of the constitutive activation of the NF-κB pathways in TC-derived cell lines. Finally, its implication in invasiveness and its overexpression in PTC samples make NIK a potential therapeutic target for advanced TC treatment.

Inhibitory effects of miR‑26b‑5p on thyroid cancer

In order to examine the inhibitory effects of microRNA (miR)‑26b‑5p on thyroid cancer (TC), the clinicopathological features and pathological tissues of 67 patients were collected. The expression levels of miR‑26b‑5p were detected in TC and paracarcinoma tissues by quantitative polymerase chain reaction, and the association between miR‑26b‑5p expression and the clinicopathological features of the patients was analyzed using t‑test or one‑way analysis of variance. In addition, B‑CPAP TC cells were infected with a lentivirus to induce miR‑26b‑5p overexpression and proliferation was detected by Cell Counting kit‑8. Subsequently, migration and invasion were detected by Transwell and Matrigel assays, respectively, and the molecular mechanism of action was investigated by western blotting. The results demonstrated that the expression levels of miR‑26b‑5p were significantly lower in TC tissues compared with paracarcinoma tissues (P<0.01), and miR‑26b‑5p was associated with lymph node metastasis (P<0.05). In addition, overexpression of miR‑26b‑5p inhibited the proliferation, invasion and migration of B‑CPAP cells. Western blot analysis demonstrated that the protein expression levels of phosphorylated glycogen synthase kinase‑3β (pGsk‑3β) were decreased, and the expression of β‑catenin was decreased in B‑CPAP cells overexpressing miR‑26b‑5p. These results demonstrated that miR‑26b‑5p may exert antitumor activity. In addition, at the molecular level, these effects may be associated with the Gsk‑3β/β‑catenin pathway.

Effect of Iodine Intake on p14ARF and p16INK4a Expression in Thyroid Papillary Carcinoma in Rats

BACKGROUND

Iodine intake is related to thyroid disease. This study investigated the effect of the amount of iodine intake on p14ARF and p16INK4a expression of thyroid papillary carcinoma in rats.

MATERIAL AND METHODS

A cohort of 240 SD rats were randomly divided into control group, low iodine, normal iodine, and high iodine groups (n=60 per group). We inoculated 2 × 10(5) papillary thyroid carcinoma (PTC) cells on the left side of the thyroid gland. After 6 and 12 weeks, serum thyroid hormone level and urine iodine level were measured in addition to morphological observations of tumor tissues. Expression of p14ARF, p16INK4a was detected by immunohistochemical staining.

RESULTS

The expression of p14ARF, p16INK4a, FT3, and FT4 levels in all iodine-treated animals were significantly lower than in the control group, while TSH level was significantly higher (P<0.05). Compared to the normal iodine group, the low and high groups had lower p14ARF and p16INK4a expression, lower FT3 and FT4 levels, higher TSH levels, and heavier tumors (P<0.05). In a further between-group comparison, p14ARF and p16INK4a expression and FT3 and FT4 levels at 12 weeks were lower than at 6 weeks. Expression of p14ARF and p16INK4a were positively correlated with FT3 and FT4, and negatively correlated with TSH and tumor weight.

CONCLUSIONS

Low and high iodine diet intake could reduce p14ARF and p16INK4a expressions and promote tumor development.