Tumor-associated macrophages (TAMs) can promote cancer initiation and progression by releasing cytokines. Previously, we have found the density of TAMs correlated with lymph node metastasis in papillary thyroid carcinoma (PTC). However, the mechanisms of how TAMs promote PTC progression remain unclear. In this study, we first showed that the TAMs density in the tumor core was associated with progressive PTC features and TAMs conditioned medium enhanced PTC cells invasion. Cytokine profiling identified a mixed M1/M2 phenotype and CXCL8 was the most consistently abundant cytokine in PTC-derived TAMs. CXCL8 receptors, CXCR1 and CXCR2, were positively stained in PTC cell lines and tissues, though no association with lymph node metastasis or extrathyroid extension. PTC cell invasion was abrogated by anti-CXCL8-neutralizing antibody, whereas addition of exogenous recombinant human CXCL8 enhanced the invasiveness. More importantly, CXCL8 promoted PTC metastasis in vivo. No difference was found for TAMs-derived CXCL8 expression in patients with and without lymph node metastasis or extrathyroid extension. These findings indicated that TAMs may facilitate PTC cell metastasis through CXCL8 and its paracrine interaction with CXCR1/2.

Background: Tumor-associated macrophages (TAMs) have recently been recognized as being important players in the tumoriogenesis of many cancers, including advanced thyroid cancer. However, a role in papillary thyroid carcinoma (PTC), the most prevalent thyroid cancer, has not been established. We hypothesized that TAMs also facilitate tumor progression in PTC. Methods: We investigated TAMs density in both benign thyroid lesions and PTC tumors by CD68 immunostaining. CD68-positive cell density was further associated with the clinicopathological characteristics of PTC patients. Finally, TAMs were isolated from PTC tumors and phenotyped by cytokine and receptor profiling. Results: The overall density of TAMs was found to be significantly higher in PTC tumors, compared with thyroid goiter and follicular adenoma. The density of TAMs was positively associated with lymph node metastasis in TNM (tumor-node-metastasis) stages III/VI compared with stages I/II. No association was observed in other common tumor features, including the BRAF mutation. The isolated TAMs presented with high levels of M2-associated cytokine and receptors, making M2 the predominant TAM phenotype. Conclusions: TAMs may play a functional role in the progression of PTC.

The weekly protocol of iv methylprednisolone therapy is more efficient and safer than the daily protocol for patients with active moderate-to-severe GO.

The genomic alterations for benign thyroid nodule, especially adenomatoid nodule, one of the most common types of hyperplasia lesion, are ill-studied. Here, we show whole-exome sequencing and/or transcriptome sequencing data on adenomatoid nodules with or without coincidental papillary thyroid carcinoma (PTC). Somatic mutation of BRAF (22/32) is only detected in PTC, while mutations in SPOP (4/38), ZNF148 (6/38) and EZH1 (3/38) are found enriched in adenomatoid nodule. In an expanded cohort of adenomatoid nodule (n=259) mutually exclusive SPOPP94R, EZH1Q571R and ZNF148 mutations are identified in 24.3% of them. Adenomatoid nodules show very few overlapped mutations and distinct gene expression patterns with their coincidental PTC. Phylogenetic tree analysis uncovers that PTCs evolved independently from their matched benign nodules. Our findings reveal that benign nodules possess a unique molecular signature that differs from PTC and provide genomic evidence for the conventional belief that PTC and benign nodules have independent origin.

Smoking, even past smoking, was an independent risk factor associated with impaired response to intravenous corticosteroids in patients with GO. Smokers with GO should be given optimised treatment strategy such as higher dose of GC or combined radiation therapy.