Epitope-Specific Antitumor Immunity Suppresses Tumor Spread in Papillary Thyroid Cancer

Thyroglobulin Antibodies and Tumor Epitope-Specific Cellular Immunity in Papillary Thyroid Cancer

Papillary thyroid carcinoma (PTC) is characterized by T cell infiltration and frequently by the presence of anti-thyroglobulin antibodies (TgAbs). The role of cellular immunity and of TbAbs in this context is a matter of debate. The aim of our study was to correlate the presence of TgAbs, tumor epitope-specific T cells and the clinical outcome of PTC patients. We studied n=183 consecutive patients with a diagnosis of PTC which were treated with total thyroidectomy plus 131I ablation. During a follow-up of in mean 97 months, most of the PTC patients had no signs of tumor relapse (n=157 patients). In contrast, one patient had serum Tg levels above the detection limit and<1 ng/ml, two patients Tg serum levels≥1 ng/ml and<2 ng/ml and n=23 patients had Tg serum levels≥2 ng/ml. Morphological signs of tumor recurrence were seen in 14 patients; all of these patients had serum Tg levels≥2 ng/ml. Importantly, with the exception of one patient, all TgAb positive PTC patients (n=27) had no signs of tumor recurrence as the serum Tg levels were below the assays functional sensitivities. Tetramer analyses revealed a higher number of tumor epitope-specific CD8+T cells in TgAb positive patients compared to TgAb negative PTC patients. In summary, we show that the occurrence of TgAbs may have an impact on the clinical outcome in PTC patients. This might be due to a tumor epitope-specific cellular immunity in PTC patients.

Harnessing Immunity to Treat Advanced Thyroid Cancer

The incidence of thyroid cancer (TC) has increased over the past 30 years. Although differentiated thyroid cancer (DTC) has a good prognosis in most patients undergoing total thyroidectomy followed by radioiodine therapy (RAI), 5-10% of patients develop metastasis. Anaplastic thyroid cancer (ATC) has a low survival rate and few effective treatments have been available to date. Recently, tyrosine kinase inhibitors (TKIs) have been successfully applied to RAI-resistant or non-responsive TC to suppress the disease. However, TC eventually develops resistance to TKIs. Immunotherapy is a promising treatment for TC, the majority of which is considered an immune-hot malignancy. Immune suppression by TC cells and immune-suppressing cells, including tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells, is complex and dynamic. Negative immune checkpoints, cytokines, vascular endothelial growth factors (VEGF), and indoleamine 2,3-dioxygenase 1 (IDO1) suppress antitumor T cells. Basic and translational advances in immune checkpoint inhibitors (ICIs), molecule-targeted therapy, tumor-specific immunotherapy, and their combinations have enabled us to overcome immune suppression and activate antitumor immune cells. This review summarizes current findings regarding the immune microenvironment, immunosuppression, immunological targets, and immunotherapy for TC and highlights the potential efficacy of immunotherapy.

The Immune Landscape of Papillary Thyroid Cancer in the Context of Autoimmune Thyroiditis

Simple Summary

The association between papillary thyroid cancer and Hashimoto’s thyroiditis went through a long-standing human debate recently elucidated by the establishment of a novel mouse model. Papillary thyroid carcinoma is an excellent model for studying the tumor immune microenvironment because it is naturally accompanied by immune cells, making it a good candidate for the treatment with immune checkpoint inhibitors.

Abstract

Papillary thyroid cancer (PTC) often co-occurs with Hashimoto’s thyroiditis, an association that has long been reported in clinical studies, remaining controversial. Experimental evidence has recently shown that pre-existing thyroiditis has a beneficial effect on PTC growth and progression by a distinctive expansion of effector memory CD8 T cells. Although the link between inflammation and PTC might involve different components of the immune system, a deep characterization of them which includes T cells, B cells and tertiary lymphoid structures, Mye-loid cells, Neutrophils, NK cells and dendritic cells will be desirable. The present review article considers the role of the adaptive and innate immune response surrounding PTC in the context of Hashimoto’s thyroiditis. This review will focus on the current knowledge by in vivo and in vitro studies specifically performed on animals’ models; thyroid cancer cells and human samples including (i) the dual role of tumor-infiltrating lymphocytes; (ii) the emerging role of B cells and tertiary lymphoid structures; (iii) the role of myeloid cells, dendritic cells, and natural killer cells; (iv) the current knowledge of the molecular biomarkers implicated in the complex link between thyroiditis and PTC and the potential implication of cancer immunotherapy in PTC patients in the context of thyroiditis.

Identification of Transcriptional Pattern Related to Immune Cell Infiltration With Gene Co-Expression Network in Papillary Thyroid Cancer

BACKGROUND

A growing body of evidence suggests that immune cell infiltration in cancer is closely related to clinical outcomes. However, there is still a lack of research on papillary thyroid cancer (PTC).

METHODS

Based on single-sample gene set enrichment analysis (SSGSEA) algorithm and weighted gene co-expression network analysis (WGCNA) tool, the infiltration level of immune cell and key modules and genes associated with the level of immune cell infiltration were identified using PTC gene expression data from The Cancer Genome Atlas (TCGA) database. In addition, the co-expression network and protein-protein interactions network analysis were used to identify the hub genes. Moreover, the immunological and clinical characteristics of these hub genes were verified in TCGA and GSE35570 datasets and quantitative real-time polymerase chain reaction (PCR). Finally, receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of hub genes.

RESULTS

Activated B cell, activated dendritic cell, CD56bright natural killer cell, CD56dim natural killer cell, Eosinophil, Gamma delta T cell, Immature dendritic cell, Macrophage, Mast cell, Monocyte, Natural killer cell, Neutrophil and Type 17 T helper cell were significantly changed between PTC and adjacent normal groups. WGCNA results showed that the black model had the highest correlation with the infiltration level of activated dendritic cells. We found 14 hub genes whose expression correlated to the infiltration level of activated dendritic cells in both TCGA and GSE35570 datasets. After validation in the TCGA dataset, the expression level of only 5 genes (C1QA, HCK, HLA-DRA, ITGB2 and TYROBP) in 14 hub genes were differentially expressed between PTC and adjacent normal groups. Meanwhile, the expression levels of these 5 hub genes were successfully validated in GSE35570 dataset. Quantitative real-time PCR results showed the expression of these 4 hub genes (except C1QA) was consistent with the results in TCGA and GSE35570 dataset. Finally, these 4 hub genes had diagnostic value to distinguish PTC and adjacent normal controls.

CONCLUSIONS

HCK, HLA-DRA, ITGB2 and TYROBP may be key diagnostic biomarkers and immunotherapy targets in PTC.

Clinical Significance of Coexistence of Hashimoto Thyroiditis and Graves' Disease with Differentiated and Medullary Thyroid Cancer

The association of Hashimoto thyroiditis and Graves' disease with papillary, follicular, and medullary thyroid cancer has not been comprehensively investigated until now. This comparative clinicopathological study of consecutive patients thyroidectomized at a surgical referral center aimed to explore interdependencies between chronic autoimmune thyroiditis and thyroid cancer. Altogether, there were 852 (58.4%) patients with papillary thyroid cancer, 181 (12.4%) patients with follicular thyroid cancer, and 426 (29.2%) patients with sporadic medullary thyroid cancer, of whom 75 (5.1%) patients also had Hashimoto thyroiditis and 40 (2.7%) patients also had Graves' disease. Patients with papillary (medians of 42 vs. 48 years; P =0.008) and follicular (medians of 33 vs. 63 years; P=0.022) thyroid cancer, unlike patients with medullary thyroid cancer (medians of 57.5 vs. 57 years; P=0.989), were younger at thyroidectomy when they had Hashimoto thyroiditis concomitantly. No such associations were seen with Graves' disease. Primary thyroid cancers tended to be more localized in conjunction with Hashimoto thyroiditis, and less so with Graves' disease, although patterns were not consistent across tumor types. In conclusion, Hashimoto thyroiditis, but not Graves' disease, may be associated with differentiated (papillary and follicular) thyroid cancer but not with medullary thyroid cancer.

Immunotherapy for advanced thyroid cancers - rationale, current advances and future strategies

In the past decade, the field of cancer immunotherapy has been revolutionized by immune checkpoint blockade (ICB) technologies. Success across a broad spectrum of cancers has led to a paradigm shift in therapy for patients with advanced cancer. Early data are now accumulating in progressive thyroid cancers treated with single-agent ICB therapies and combination approaches that incorporate ICB technologies. This Review discusses our current knowledge of the immune response in thyroid cancers, the latest and ongoing immune-based approaches, and the future of immunotherapies in thyroid cancer. Physiologically relevant preclinical mouse models and human correlative research studies will inform development of the next stage of immune-based therapies for patients with advanced thyroid cancer.

Immune-related key gene CLDN10 correlates with lymph node metastasis but predicts favorable prognosis in papillary thyroid carcinoma

The functions of immune cells in lymph node metastasis (LNM) have attracted considerable attention. This study aimed to screen the key immune-related and LNM-related genes in PTC. In the discovery phase, the immune-related genes in LNM were screened by using bioinformatics methods. In the validation phases, the association of the genes with LNM was first confirmed in a cohort from The Cancer Genome Atlas and a cohort based on a tissue chip. Then, the relationship of the genes with immune cell infiltration was further explored. Consequently, CLDN10 was identified, and its high expression was correlated with the presence of LNM in PTC but predicted a favorable prognosis. High CLDN10 expression was positively correlated with the infiltration of several immune cells, such as B cells, CD8+T cells, and macrophages. High CLDN10 expression may improve the outcomes of patients with PTC by increasing immune cell infiltration, although it might be associated with LNM. In conclusion, although CLDN1 might be correlated with LNM, it may also increase the infiltration of immune cells, including CD8+T cells and macrophages, and improve the clinical outcomes of patients with PTC. The effects of tumor purity and immune cell infiltration need to be considered in prognosis evaluation.

Recent advances in understanding immune phenotypes of thyroid carcinomas: prognostication and emerging therapies

Tumors modulate the host immune cells within their microenvironment to avoid recognition and elimination by our immune system, a phenotype called cancer immune escape. Different mechanisms responsible for cancer immune escape that result either in decreased tumor immunogenicity or in increased tumor immunosuppressive activity have been identified. Recently, various immunotherapeutic approaches have been developed with the aim to revert tumor immune escape. The aims of this review are to explore the immunological aspects of thyroid cancer and to assess whether these features can be exploited in the prognosis and treatment of advanced forms of this disease. Therefore, we will describe the immune landscape and phenotypes of thyroid cancer, summarize studies investigating the expression of immunomodulatory molecules, and finally describe the preclinical and clinical trials investigating the utility of immunotherapies in the management of thyroid cancer.

The aim of this review is to explore the immunological aspects of thyroid cancer and to assess whether these features can be exploited in the prognosis and treatment of advanced forms of this disease. Therefore, we will describe the immune-landscape and phenotypes of thyroid cancer, we will summarize studies investigating the expression of immunomodulatory molecules, and we will finally describe the preclinical and clinical trials investigating the utility of immunotherapies in the management of thyroid cancer.

Thyroid-Specific T Cells in Patients With Differentiated Thyroid Cancer: Implications for Immune-Based Therapies?

This editorial reviews the recent paper by Ehlers et al and provides a perspective on thyroid cancer immunology.