Immune Landscape of Thyroid Cancers: New Insights

Immune microenvironment in papillary thyroid carcinoma: roles of immune cells and checkpoints in disease progression and therapeutic implications

Papillary thyroid cancer (PTC) is the most common type of primary thyroid cancer. Despite the low malignancy and relatively good prognosis, some PTC cases are highly aggressive and even develop refractory cancer in the thyroid. Growing evidence suggested that microenvironment in tumor affected PTC biological behavior due to different immune states. Different interconnected components in the immune system influence and participate in tumor invasion, and are closely related to PTC metastasis. Immune cells and molecules are widely distributed in PTC tissues. Their quantity and proportion vary with the host's immune status, which suggests that immunotherapy may be a very promising therapeutic modality for PTC. In this paper, we review the role of immune cells and immune checkpoints in PTC immune microenvironment based on the characteristics of the PTC tumor microenvironment.

Causal effects of autoimmune diseases on thyroid cancer: a two-sample Mendelian randomization study

Background

Although numerous studies had revealed associations between autoimmune diseases (AIDs) and thyroid cancer (TC), the potential causal associations between the two remain poorly defined.

Methods

Using five approaches, two-sample Mendelian randomization (MR) analyses were carried out to determine the causal effects of 12 major AIDs on risk of TC. The sensitivity analyses were conducted to verify the reliability of the analysis. The reverse MR analysis was performed to evaluate the possibility of reverse causation.

Results

The results showed a significant causal association of systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC) on the risk of TC. Genetically predicted PBC elevated the risk of TC (OR = 1.46, 95% CI = 1.06-2.02, p = 0.021). The risk of TC was also increased by genetically predicted SLE (OR = 6.52, 95% CI = 1.38-30.84, p = 0.018) with heterogeneity. After outlier-corrected analyses, the results still suggested that genetically predicted SLE increased the risk of TC (p = 0.019). No evidence of a causal relationship between the remaining 10 AIDs and TC was observed. No reverse causal effects of TC on AIDs were found in reverse MR analysis.

Conclusion

These findings support a significant causal association of SLE/PBC on the increased risk of TC, indicating that patients with SLE/PBC should be under a close monitoring of TC.

Predominance of CD4+ T cells in metastatic cervical lymph nodes in papillary thyroid carcinoma

Background

Papillary thyroid carcinoma has become increasingly prevalent over the years. Avoiding unnecessary treatments and the risk of complications is essential, as well as understanding the mechanisms of tumor progression and the conditions that indicate a worse prognosis. Assessment of the tumor microenvironment can allow us understand how the immune system organizes itself to contain neoplastic progression.

Methods

We compared characteristics related to the lymphocytic subpopulations in the thyroid tumor microenvironment and lymph nodes in two groups, with and without lymph node metastatic involvement.

Results

Of the 400 cases followed up at a thyroid cancer reference service, 32 were selected, of which, 13 cases did not present lymph node metastasis (N0 group) and 19 had lymph node involvement (N1 group). Clinical data were collected, and immunohistochemical reactions were performed for markers CD4, CD8, FoxP3, CD25, and CD20 in lymph nodes and peritumoral infiltrate. We found that the N1 group had larger tumor sizes, higher risk staging, higher frequency of extrathyroidal extension, shorter disease-free times, and higher expression of CD4+ T lymphocytes in lymph nodes; however, there was no difference in the expression of other markers or in the pattern of lymphocyte distribution in the lymph node.

Conclusion

In cervical lymph nodes, the higher frequency of CD4+ T lymphocytes is related to the presence of metastasis. However, there were no differences in lymphocytic subpopulations in the thyroid tumor microenvironment. The absence of changes in unaffected lymph nodes could not predict any tumor behavior.

Medullary Thyroid Cancer: Molecular Drivers and Immune Cellular Milieu of the Tumour Microenvironment-Implications for Systemic Treatment

In this review, we explore the underlying molecular biology of medullary thyroid carcinoma (MTC) and its interplay with the host immune system. MTC is consistently driven by a small number of specific pathogenic variants, beyond which few additional genetic events are required for tumorigenesis. This explains the exceedingly low tumour mutational burden seen in most MTC, in contrast to other cancers. However, because of the low tumour mutational burden (TMB), there is a correspondingly low level of tumour-associated neoantigens that are presented to the host immune system. This reduces tumour visibility and vigour of the anti-tumour immune response and suggests the efficacy of immunotherapy in MTC is likely to be poor, acknowledging this inference is largely based on the extrapolation of data from other tumour types. The dominance of specific RET (REarranged during Transfection) pathogenic variants in MTC tumorigenesis rationalizes the observed efficacy of the targeted RET-specific tyrosine kinase inhibitors (TKIs) in comparison to multi-kinase inhibitors (MKIs). Therapeutic durability of pathway inhibitors is an ongoing research focus. It may be limited by the selection pressure TKI treatment creates, promoting survival of resistant tumour cell clones that can escape pathway inhibition through binding-site mutations, activation of alternate pathways, and modulation of the cellular and cytokine milieu of the tumour microenvironment (TME).

Selective anti-CXCR2 receptor blockade by AZD5069 inhibits CXCL8-mediated pro-tumorigenic activity in human thyroid cancer cells in vitro

BACKGROUND

Thyroid cancer is the most common endocrine malignancy. Current therapies are successful, however some patients progress to therapeutically refractive disease. The immunotherapeutic potential of the CXCL8-chemokine/CXCR2-chemokine-receptor system is currently being explored in numerous human cancers. This study aimed to evaluate if the targeting of CXCR2 by its selective antagonist, AZD5069, could modulate CXCL8-mediated pro-tumorigenic effects in thyroid-cancer (TC) cells in vitro.

METHODS

Normal human primary thyroid cells (NHT) and TC cell lines TPC-1 (RET/PTC), BCPAP, 8505C and 8305C (BRAFV600e) were treated with AZD5069 (100 pM-10 µM) over a time-course. Viability and proliferation were assessed by WST-1 and crystal violet assays. CXCL8 and CXCR2 mRNA were evaluated by RT-PCR. CXCL8-protein concentrations were measured in cell culture supernatants by ELISA. CXCR2 on cell surface was evaluated by flow-cytometry. Cell-migration was assessed by trans-well-migration chamber-system.

RESULTS

AZD5069 exerted negligible effects on cell proliferation or viability. AZD5069 significantly reduced CXCR2, (but not CXCL8) mRNAs in all cell types. CXCR2 was reduced on the membrane of some TC cell lines. A significant reduction of the CXCL8 secretion was found in TPC-1 cells (basal-secretion) and NHT (TNFα-induced secretion). AZD5069 significantly reduced basal and CXCL8-induced migration in NHT and different TC cells.

CONCLUSIONS

Our findings confirm the involvement of the CXCL8/CXCR2-axis in promoting pro-tumorigenic effects in TC cells, further demonstrating its immunotherapeutic significance in human cancer.

Emerging therapeutic options for follicular-derived thyroid cancer in the era of immunotherapy

Although most follicular-derived thyroid cancers are well differentiated and have an overall excellent prognosis following treatment with surgery and radioiodine, management of advanced thyroid cancers, including iodine refractory disease and poorly differentiated/undifferentiated subtypes, is more challenging. Over the past decade, better understanding of the genetic drivers and immune milieu of advanced thyroid cancers has led to significant progress in the management of these patients. Numerous targeted kinase inhibitors are now approved by the U.S Food and Drug administration (FDA) for the treatment of advanced, radioiodine refractory differentiated thyroid cancers (DTC) as well as anaplastic thyroid cancer (ATC). Immunotherapy has also been thoroughly studied and has shown promise in selected cases. In this review, we summarize the progress in the understanding of the genetic landscape and the cellular and molecular basis of radioiodine refractory-DTC and ATC, as well as discuss the current treatment options and future therapeutic avenues.

Research progress of immunotherapy against anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is the most aggressive type of thyroid cancer. While ATC is rare, its mortality is high. Standard treatments, such as surgery, radiotherapy, and chemotherapy, have demonstrated limited efficacy in managing ATC. However, the advent of immunotherapy has significantly improved the prognosis for patients with ATC. Immunotherapy effectively targets and eliminates tumor cells by using the power of the body's immune cells. The neoantigen is an atypical protein generated by somatic mutation, is exclusively observed in neoplastic cells, and is devoid of central tolerance. Neoantigens exhibit enhanced specificity towards tumor cells and display robust immunogenic properties. Currently, neoantigen therapy is primarily applied in immune checkpoint inhibitors and cellular immunotherapy, encompassing adoptive immunotherapy and tumor vaccines. This study discusses the mechanism, tumor microenvironment, clinical trials, adverse events, limitations and future directions associated with ATC immunotherapy.

The relationship between thyroid peroxidase antibody and differentiated thyroid cancer: a systematic review and meta-analysis

Background

Thyroglobulin antibody (TgAb) has been found to be associated with the occurrence and development of differentiated thyroid cancer (DTC) for several years, but there is still controversy over whether thyroid peroxidase antibody (TPOAb) is related to differentiated thyroid cancer.

Methods

We scrutinized relevant studies published up to July 2023 across four major databases including PubMed, Embase, Cochrane Library, and Web of Science, to examine the association between TPOAb and DTC. Clinical outcome measures include the incidence of DTC, tumor size, extrathyroidal invasion, lymph node metastasis, multifocality, recurrence and bilaterality.

Results

12 original studies were included, involving a total of 20,330 subjects. Our analysis of the included studies revealed that TPOAb+ individuals exhibited a higher risk of developing DTC (OR=1.57 [95% CI: 1.00-2.45], p=0.049) than TPOAb- individuals. Furthermore, TPOAb+ DTC patients were more prone to present with bilateral (OR=1.40 [95% CI: 1.21-1.62], p<0.00001) and multifocal (OR=1.40 [95% CI: 1.23-1.60], p<0.00001) tumors than TPOAb- patients. Sensitivity analysis indicated a high sensitivity for these three findings. No significant differences in the risk of extrathyroidal extension and lymph node metastasis, recurrence rate, tumor size, were observed between TPOAb+ and TPOAb- DTC patients.

Conclusion

The presence of TPOAb is correlated with an increase prevalence of DTC. However, its effectiveness as a prognostic marker for DTC patients warrants further investigation.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023448824.

Integration of scRNA and bulk RNA-sequence to construct the 5-gene molecular prognostic model based on the heterogeneity of thyroid carcinoma endothelial cell

Thyroid cancer (TC) is a kind of cancer with high heterogeneity, which leads to significant difference in prognosis. The prognostic molecular processes are not well understood. Cancer cells and tumor microenvironment (TME) cells jointly determine the heterogeneity. However, quite a little attention was paid to cells in the TME in the past years. In this study, we not only reveal that endothelial cells (ECs) are strongly associated with the progress of papillary thyroid cancer (PTC) using single-cell RNA-seq (scRNA-seq) data downloaded from Gene Expression Omnibus (GEO) and WGCNA, but also screen 5 crucial genes of ECs: CLDN5, ABCG2, NOTCH4, PLAT, and TMEM47. Furthermore, the 5-gene molecular prognostic model is constructed, which can predict how well a patient will do on PD-L1 blockade immunotherapy for TC and evaluate prognosis. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrates that PLAT is decreased in TC and the increase of PLAT can restrain the migratory capacity of TC cells. Meanwhile, in TC cells, PLAT suppresses VEGFa/VEGFR2-mediated human umbilical vascular endothelial cell (HUVEC) proliferation and tube formation. Totally, we construct the 5-gene molecular prognostic model from the perspective of EC and provide a new idea for immunotherapy of TC.

Leveraging molecular targeted drugs and immune checkpoint inhibitors treat advanced thyroid carcinoma to achieve thyroid carcinoma redifferentiation

Thyroid cancer can be classified into three different types based on the degree of differentiation: well-differentiated, poorly differentiated, and anaplastic thyroid carcinoma. Well-differentiated thyroid cancer refers to cancer cells that closely resemble normal thyroid cells, while poorly differentiated and anaplastic thyroid carcinoma are characterized by cells that have lost their resemblance to normal thyroid cells. Advanced thyroid carcinoma, regardless of its degree of differentiation, is known to have a higher likelihood of disease progression and is generally associated with a poor prognosis. However, the process through which well-differentiated thyroid carcinoma transforms into anaplastic thyroid carcinoma, also known as "dedifferentiation", has been a subject of intensive research. In recent years, there have been significant breakthroughs in the treatment of refractory advanced thyroid cancer. Clinical studies have been conducted to evaluate the efficacy and safety of molecular targeted drugs and immune checkpoint inhibitors in the treatment of dedifferentiated thyroid cancer. These drugs work by targeting specific molecules or proteins in cancer cells to inhibit their growth or by enhancing the body's immune response against the cancer cells. This article aims to explore some of the possible mechanisms behind the dedifferentiation process in well-differentiated thyroid carcinoma. It also discusses the clinical effects of molecular targeted drugs and immune checkpoint inhibitors in thyroid cancer patients with different degrees of differentiation. Furthermore, it offers insights into the future trends in the treatment of advanced thyroid cancer, highlighting the potential for improved outcomes and better patient care.

Autoimmune Thyroid Disease and Differentiated Thyroid Carcinoma: A Review of the Mechanisms That Explain an Intriguing and Exciting Relationship

Autoimmune thyroid disease is a complex and highly frequent disease, where a wide variety of genetic, epigenetic and environmental factors (among others) come together and interact, and is characterized by the presence of two clinical outcomes: hypothyroidism (in Hashimoto's thyroiditis) and hyperthyroidism (in Graves-Basedow disease). For its part, differentiated thyroid carcinoma (mainly papillary carcinoma) is the most common type of cancer affecting the thyroid (and one of the most prevalent worldwide). An important co-occurrence between autoimmune thyroid disease and differentiated thyroid carcinoma has been documented. In this article, studies that have evaluated possible associations and relationships between autoimmune thyroid disease and differentiated thyroid cancer are systematically described and summarized. To date, the underlying mechanism that explains this association is inflammation; however, the characteristics and designs of the studies evaluated do not yet allow a causal relationship between the two entities to be established. These aspects have made it difficult to establish "causality" in the continuum of the pathogenesis between both conditions.

Identification and clinical value of a new ceRNA axis (TIMP3/hsa-miR-181b-5p/PAX8-AS1) in thyroid cancer

Background

Thyroid cancer (TC) is a prevalent and increasingly common malignant tumor. In most cases, TC progresses slowly and runs a virtually benign course. However, challenges remain with the treatment of refractory TC, which does not respond to traditional management or is subject to relapse or metastasis. Therefore, new therapeutic regimens for TC patients with poor outcomes are urgently needed.

Methods

The differentially expressed RNAs were identified from the expression profile data of RNA from TC downloaded from The Cancer Genome Atlas database. Multiple databases were utilized to investigate the regulatory relationship among RNAs. Subsequently, a competitive endogenous RNA (ceRNA) network was established to elucidate the ceRNA axis that is responsible for the clinical prognosis of TC. To understand the potential mechanism of ceRNA axis in TC, location analysis, functional enrichment analysis, and immune-related analysis were conducted.

Results

A ceRNA network of TC was constructed, and the TIMP3/hsa-miR-181b-5p/PAX8-AS1 ceRNA axis associated with the prognosis of TC was successfully identified. Our results showed that the axis might influence the prognosis of TC through its regulation of regulating tumor immunity.

Conclusions

Our findings provide evidence that TIMP3/hsa-miR-181b-5p/PAX8-AS1 axis is significantly related to the prognosis of TC. The molecules involved in this axis may serve as novel therapeutic approaches for TC treatment.

Integrative single-cell transcriptome analysis reveals immune suppressive landscape in the anaplastic thyroid cancer

The tumor immune microenvironment (TIME) in ATC is a complex and diverse ecosystem. It is essential to have a comprehensive understanding to improve cancer treatment and prognosis. However, TIME of ATC and the dynamic changes with PTC has not been revealed at the single-cell level. Here, we performed an integrative single-cell analysis of PTC and ATC primary tumor samples. We found that immunosuppressive cells and molecules dominated the TIME in ATC. Specifically, the level of infiltration of exhausted CD8+ T cells, and M2 macrophages was increased, and that of NK cells, B cells, and M1 macrophages was decreased. The cytotoxicity of CD8+ T cells, γδT cells, and NK cells was decreased, and immune checkpoint molecules, such as LAG3, PD1, HAVCR2, and TIGIT were highly expressed in ATC. Our findings contribute to the comprehension of TIME in both PTC and ATC, offering insights into the immunosuppressive factors specifically associated with ATC. Targeting these immunosuppressive factors may activate the anti-tumor immune response in ATC.

Translocated HMGB3 is involved in papillary thyroid cancer progression by activating cytoplasmic TLR3 and transmembrane TREM1

The family of high mobility group box (HMGB) proteins participates in various biological processes including immunity, inflammation, as well as cancer formation and progression. However, its role in thyroid cancer remains to be clarified. We performed quantitative RT-PCR (qRT-PCR), western blot, enzyme-linked immunosorbent, immunohistochemistry, and immunofluorescence assays to evaluate the expression level and subcellular location of HMGB3. The effects of HMGB3 knockdown on malignant biological behaviors of thyroid cancer were determined by cell proliferation assays, cell cycle and apoptosis assays, and transwell chamber migration and invasion assays. Differential expression genes (DEGs) altered by HMGB3 were analyzed using the Ingenuity Pathway Analysis (IPA) and TRRUST v2 database. HMGB3 correlated pathways predicted by bioinformatic analysis were then confirmed using western blot, co-immunoprecipitation, dual-luciferase reporter assay, and flow cytometry. We found that HMGB3 is overexpressed and its downregulation inhibits cell viability, promotes cell apoptosis and cell cycle arrest, and suppresses cell migration and invasion in thyroid cancer. In PTC, both tissue and serum levels of HMGB3 are elevated and are correlated with lymph node metastasis and advanced tumor stage. Mechanistically, we observed the translocation of HMGB3 in PTC, induced at least partially by hypoxia. Cytoplasmic HMGB3 activates nucleic-acid-mediated TLR3/NF-κB signaling and extracellular HMGB3 interacts with the transmembrane TREM1 receptor in PTC. This study demonstrates the oncogenic role of HMGB3 cytoplasmic and extracellular translocation in papillary thyroid cancers; we recommend its future use as a potential circulating biomarker and therapeutic target for PTC.

Tumor-associated macrophages as a potential therapeutic target in thyroid cancers

Macrophages are important precursor cell types of the innate immune system and bridge adaptive immune responses through the antigen presentation system. Meanwhile, macrophages constitute substantial portion of the stromal cells in the tumor microenvironment (TME) (referred to as tumor-associated macrophages, or TAMs) and exhibit conflicting roles in the development, invasion, and metastasis of thyroid cancer (TC). Moreover, TAMs play a crucial role to the behavior of TC due to their high degree of infiltration and prognostic relevance. Generally, TAMs can be divided into two subgroups; M1-like TAMs are capable of directly kill tumor cells, and recruiting and activating other immune cells in the early stages of cancer. However, due to changes in the TME, M2-like TAMs gradually increase and promote tumor progression. This review aims to discuss the impact of TAMs on TC, including their role in tumor promotion, gene mutation, and other factors related to the polarization of TAMs. Finally, we will explore the M2-like TAM-centered therapeutic strategies, including chemotherapy, clinical trials, and combinatorial immunotherapy.

A novel prognostic signature and immune microenvironment characteristics associated with disulfidptosis in papillary thyroid carcinoma based on single-cell RNA sequencing

Background: Disulfidptosis is a newly discovered form of regulated cell death. The research on disulfidptosis and tumor progression remains unclear. Our research aims to explore the relationship between disulfidptosis-related genes (DRGs) and the clinical outcomes of papillary thyroid carcinoma (PTC), and its interaction on the tumor microenvironment. Methods: The single-cell RNA seq data of PTC was collected from GEO dataset GSE191288. We illustrated the expression patterns of disulfidptosis-related genes in different cellular components in thyroid cancer. LASSO analyses were performed to construct a disulfidptosis associated risk model in TCGA-THCA database. GO and KEGG analyses were used for functional analyses. CIBERSORT and ESTIMATE algorithm helped with the immune infiltration estimation. qRT‒PCR and flow cytometry was performed to validate the hub gene expression and immune infiltration in clinical samples. Results: We clustered PTC scRNA seq data into 8 annotated cell types. With further DRGs based scoring analyses, we found endothelial cells exhibited the most relationship with disulfidptosis. A 4-gene risk model was established based on the expression pattern of DRGs related endothelial cell subset. The risk model showed good independent prognostic value in both training and validation dataset. Functional enrichment and genomic feature analysis exhibited the significant correlation between tumor immune infiltration and the signature. The results of flow cytometry and immune infiltration estimation showed the higher risk scores was related to immuno-suppressive tumor microenvironment in PTC. Conclusion: Our study exhibited the role of disulfidptosis based signature in the regulation of tumor immune microenvironment and the survival of PTC patients. A 4-gene prognostic signature (including SNAI1, STC1, PKHD1L1 and ANKRD37) was built on the basis of disulfidptosis related endothelial cells. The significance of clinical outcome and immune infiltration pattern was validated robustly.

New Insights into Immune Cells and Immunotherapy for Thyroid Cancer

Thyroid cancer (TC) is the most common endocrine malignancy worldwide, and the incidence of TC has gradually increased in recent decades. Differentiated thyroid cancer (DTC) is the most common subtype and has a good prognosis. However, advanced DTC patients with recurrence, metastasis and iodine refractoriness, as well as more aggressive subtypes such as poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC), still pose a great challenge for clinical management. Therefore, it is necessary to continue to explore the inherent molecular heterogeneity of different TC subtypes and the global landscape of the tumor immune microenvironment (TIME) to find new potential therapeutic targets. Immunotherapy is a promising therapeutic strategy that can be used alone or in combination with drugs targeting tumor-driven genes. This article focuses on the genomic characteristics, tumor-associated immune cell infiltration and immune checkpoint expression of different subtypes of TC patients to provide guidance for immunotherapy.

HHV-6A Infection of Papillary Thyroid Cancer Cells Induces Several Effects Related to Cancer Progression

Recent studies have shown that thyrocytes are permissive to HHV-6A infection and that the virus may contribute to the pathogenesis of autoimmune thyroiditis. Thyroid autoimmune diseases increase the risk of papillary cancer, which is not surprising considering that chronic inflammation activates pathways that are also pro-oncogenic. Moreover, in this condition, cell proliferation is stimulated as an attempt to repair tissue damage caused by the inflammatory process. Interestingly, it has been reported that the well-differentiated papillary thyroid carcinoma (PTC), the less aggressive form of thyroid tumor, may progress to the more aggressive follicular thyroid carcinoma (FTC) and eventually to the anaplastic thyroid carcinoma (ATC), and that to such progression contributes the presence of an inflammatory/immune suppressive tumor microenvironment. In this study, we investigated whether papillary tumor cells (BCPAP) could be infected by human herpes virus-6A (HHV-6A), and if viral infection could induce effects related to cancer progression. We found that the virus dysregulated the expression of several microRNAs, such as miR-155, miR-9, and the miR-221/222 cluster, which are involved in different steps of carcinogenesis, and increased the secretion of pro-inflammatory cytokines, particularly IL-6, which may also sustain thyroid tumor cell growth and promote cancer progression. Genomic instability and the expression of PTEN, reported to act as an oncogene in mutp53-carrying cells such as BCPAP, also increased following HHV-6A-infection. These findings suggest that a ubiquitous herpesvirus such as HHV-6A, which displays a marked tropism for thyrocytes, could be involved in the progression of PTC towards more aggressive forms of thyroid tumor.

The influence of stimulated thyroglobulin and lymphocyte subsets before radioiodine therapy on the therapeutic response in patients with intermediate- and high-risk papillary thyroid carcinoma

The aim of the present study was to investigate the factors influencing the short-term response to the initial radioiodine therapy (RT) course in patients with intermediate- and high-risk papillary thyroid carcinoma (PTC). A total of 182 patients with intermediate- and high-risk PTC who underwent RT in our hospital from March 2018 to October 2020 were retrospectively enrolled. The patients were divided into incomplete response (IR) and nonincomplete response (Non-IR) groups according to the response observed in clinical follow-up within 6-12 months after RT. Univariate and multivariate logistic regression analyses were used to investigate the effects of 15 observed factors on the response to RT. Receiver operating characteristic (ROC) curve analysis was used to determine the value of factors found to be significant in multivariate analyses for predicting an IR. A total of 182 patients with intermediate- and high-risk PTC were analyzed; the percentage of patients with a Non-IR was 61.54% (112/182), and the percentage of patients with an IR was 38.46% (70/182). The CD4+ T-cell percentage (t = 4.757, P = 0.000), CD4/CD8 (z = - 2.632, P = 0.008), stimulated thyroglobulin (sTg) level (z = - 8.273, P = 0.000) and M stage (χ2 = 17.823, P = 0.000) of the two groups were significantly different. Multivariate analysis showed that only the sTg level (OR: 1.116, 95% CI 1.068-1.165, P < 0.001) and CD4+ T-cell percentage (OR: 0.909, 95% CI 0.854-0.968, P = 0.003) were independent factors associated with the therapeutic response to RT. The cutoff sTg level and CD4+ T-cell percentage for predicting an IR were 7.62 μg/L and 40.95%, respectively. The sTg level and CD4+ T-cell percentage were verified to be independent predictive factors of RT response. Higher sTg levels and lower CD4+ T-cell percentages were related to an IR in patients with intermediate- and high-risk PTC.

Upregulation of dendrocyte-expressed seven transmembrane protein is associated with unfavorable outcomes in differentiated thyroid cancer

PURPOSE

Dendritic cell infiltrates are increased in thyroid cancer but may have a defective ability to provoke effective immune responses. In this study, we aimed to identify potential thyroid cancer biomarkers linked to dendritic cell development and evaluate their prognostic relevance.

METHODS

Through a bioinformatics search, we identified the dendrocyte-expressed seven transmembrane protein (DCSTAMP) as a prognostic gene involved in dendritic cell differentiation for thyroid cancer. Immunohistochemical analyses of DCSTAMP expression were performed and correlated with clinical outcomes.

RESULTS

DCSTAMP was overexpressed in a variety of types of thyroid cancers, while normal thyroid tissue or benign thyroid lesions exhibited low or undetectable DCSTAMP immunoreactivity. The results of automated quantification were consistent with subjective semiquantitative scoring. Among 144 patients with differentiated thyroid cancer, high DCSTAMP expression was associated with papillary tumor type (p < 0.001), extrathyroidal extension (p = 0.007), lymph node metastasis (p < 0.001), and BRAF V600E mutation (p = 0.029). Patients with tumors showing high DCSTAMP expression had shorter overall (p = 0.027) and recurrence-free (p = 0.042) survival.

CONCLUSION

This study provides the first evidence of DCSTAMP overexpression in thyroid cancer. Apart from the prognostic implications, studies are needed to explore its potential immunomodulatory role in thyroid cancer.

SPRY4 as a Potential Mediator of the Anti-Tumoral Role of Macrophages in Anaplastic Thyroid Cancer Cells

Anaplastic thyroid carcinoma (ATC) is the most lethal subtype of thyroid cancer, with high invasive and metastatic potential, not responding to conventional treatments. Its aggressiveness may be influenced by macrophages, which are abundant cells in the tumor microenvironment. To investigate the role of macrophages in ATC aggressiveness, indirect co-cultures were established between ATC cell lines and THP-1-derived macrophages. Macrophages significantly increased both the migration and invasion of T235 cells (p < 0.01; p < 0.01), contrasting with a decrease in C3948 (p < 0.001; p < 0.05), with mild effects in T238 migration (p < 0.01) and C643 invasion (p < 0.05). Flow cytometry showed upregulation of CD80 (pro-inflammatory, anti-tumoral) and downregulation of CD163 (anti-inflammatory, pro-tumoral) in macrophages from co-culture with T235 (p < 0.05) and C3948 (p < 0.05), respectively. Accordingly, we found an upregulation of secreted pro-inflammatory mediators (e.g., GM-CSF, IL-1α; p < 0.05) in C3948-macrophage co-cultures. Proteomic analysis showed the upregulation of SPRY4, an inhibitor of the MAPK pathway, in C3948 cells from co-culture. SPRY4 silencing promoted cancer cell invasion, reverting the reduced invasion of C3948 caused by macrophages. Our findings support that macrophages play a role in ATC cell aggressiveness. SPRY4 is a possible modulator of macrophage-ATC cell communication, with a tumor suppressor role relevant for therapeutic purposes.

FDG uptake reflects an immune-enriched subtype of thyroid cancer: Clinical implications of imaging-based molecular characterization

INTRODUCTION

Iodine and FDG uptakes have been established as methods to define the biological properties of thyroid cancer. As various cells in the tumor microenvironment (TME) affect tumor metabolism, we investigated the association between glucose metabolism in thyroid cancer and the TME using transcriptomic analyses.

METHODS

We used F-18 FDG PET and RNA sequencing data of thyroid cancer to find associations between TME cell types and glucose metabolism. In addition, publicly available single-cell RNA sequencing data of papillary thyroid cancer was used to investigate glucose metabolism in cell types of the TME. The correlations between the FDG uptake and biological properties of the TME, including glucose metabolism and tumor differentiation score (TDS) were evaluated. Estimation of the proportions of immune and cancer cells (EPIC) was performed. The biological properties of each cell type were also assessed in the single-cell RNA sequencing data.

RESULTS

FDG uptake showed a positive correlation with the enrichment score of macrophages and glycolysis activity. In single-cell RNA sequencing, immune cells had both high glucose transporters (GLUTs) and glycolysis signatures, while thyrocytes including cancer cells showed relatively low GLUTs and glycolysis signatures, suggesting that FDG uptake mainly occurred in immune cells of the TME. Moreover, the high GLUTs of myeloid cells were negatively associated with TDS.

CONCLUSIONS

Our findings suggest that thyroid cancer with high FDG uptake can be mediated by enriched immune cells of the TME. We suggest that FDG uptake in thyroid cancer could be a marker for the immune-rich type and provide clinical implications for treatment stratification.

Mining Prognostic Biomarkers of Thyroid Cancer Patients Based on the Immune-Related Genes and Development of a Reliable Prognostic Risk Model

PURPOSE

Tumor immunity serves an essential role in the occurrence and development of thyroid cancer (THCA). The aim of this study is to establish an immune-related prognostic model for THCA patients by using immune-related genes (IRGs).

METHODS

Wilcox test was used to screen the differentially expressed immune-related genes (DEIRGs) in THCA and normal tissues, then the DEIRGs related to prognosis were identified using univariate Cox regression analysis. According to The Cancer Genome Atlas (TCGA) cohort, we developed a least absolute shrinkage and selection operator (LASSO) regression prognostic model and performed validation analyses regard to the predictive value of the model in internal (TCGA) and external (International Cancer Genome Consortium) cohorts respectively. Finally, we analyzed the correlation among the prognostic model, clinical variables, and immune cell infiltration.

RESULTS

Eighty-two of 2,498 IRGs were differentially expressed between THCA and normal tissues, and 18 of them were related to prognosis. LASSO Cox regression analysis identified seven DEIRGs with the greatest prognostic value to construct the prognostic model. The risk model showed high predictive value for the survival of THCA in two independent cohorts. The risk score according to the risk model was positively associated with poor survival and the infiltration levels of immune cells, it can evaluate the prognosis of THCA patients independent of any other clinicopathologic feature. The prognostic value and genetic alternations of seven risk genes were evaluated separately.

CONCLUSION

Our study established and verified a dependable prognostic model associated with immune for THCA, both the identified IRGs and immune-related risk model were clinically significant, which is conducive to promoting individualized immunotherapy against THCA.

The Tumor Microenvironment and the Estrogen Loop in Thyroid Cancer

Thyroid cancer (TC) cells employ multiple signaling pathways, such as PI3K/AKT/mTOR and RAS/Raf/MAPK, fostering cell proliferation, survival and metastasis. Through a complex interplay with immune cells, inflammatory mediators and stroma, TC cells support an immunosuppressive, inflamed, pro-carcinogenic TME. Moreover, the participation of estrogens in TC pathogenesis has previously been hypothesized, in view of the higher TC incidence observed among females. In this respect, the interactions between estrogens and the TME in TC could represent a relevant, unexplored area of research. We thereby collectively reviewed the available evidence concerning the potential carcinogenic role of estrogens in TC, specifically focusing on their crosstalk with the TME.

Extra-Cellular Vesicles Derived from Thyroid Cancer Cells Promote the Epithelial to Mesenchymal Transition (EMT) and the Transfer of Malignant Phenotypes through Immune Mediated Mechanisms

Thyroid cancer is the most common endocrine cancer, and its incidence is increasing in many countries around the world. Among thyroid cancers, the papillary thyroid cancer (PTC) histotype is particularly prevalent. A small percentage of papillary tumors is associated with metastases and aggressive behavior due to de-differentiation obtained through the epithelial-mesenchymal transition (EMT) by which epithelial thyroid cells acquire a fibroblast-like morphology, reduce cellular adhesion, increase motility and expression of mesenchymal proteins. The tumor microenvironment plays an important role in promoting an aggressive phenotype through hypoxia and the secretion of HMGB1 and other factors. Hypoxia has been shown to drastically change the tumor cell phenotype and has been associated with increasing metastatic and migratory behavior. Cells transfer information to neighboring cells or distant locations by releasing extracellular membrane vesicles (EVs) that contain key molecules, such as mRNAs, microRNAs (miRNAs), and proteins, that are able to modify protein expression in recipient cells. In this study, we investigated the potential role of EVs released by the anaplastic cancer cell line CAL-62 in inducing a malignant phenotype in a papillary cancer cell line (BCPAP).

An integrative analysis of the tumor suppressors and oncogenes from sexual dimorphism and gene expression alteration features in thyroid cancer

BACKGROUND

The incidence of thyroid cancer has risen rapidly over the last decades. Although mortality rates are relatively low compared to other cancers, the rate of new cases started to increase in the early 2000s. While tumor suppressors and oncogenes were recently identified in thyroid cancer, the potential roles of these genes in thyroid cancer remain unclear.

OBJECTIVE

Analyze the roles and functions of tumor suppressors and oncogenes in thyroid cancer.

METHODS

Thyroid cancer data were collected from public databases, such as the UCSC Xena database of TCGA thyroid cancer, TISIDB, and UALCAN. The genes frequently associated with unfavorable thyroid cancer were examined and validated. The association of these target genes with thyroid tumorigenesis, stages, subtypes, and survival rates were analyzed. Additionally, the genes aberrantly expressed in thyroid cancer and significantly involved in thyroid tumorigenesis, stages, subtypes, and survival rates were identified.

RESULTS

Female sex was identified as a risk factor for thyroid cancer. The expression of PAPSS2, PDLIM3, COPZ2, ALDH1B1, ANTXR1, GUF1, and SENP6 negatively correlated with thyroid cancer prognosis.

CONCLUSION

Female sex was a risk factor for thyroid cancer. In addition, our analysis suggested that PAPSS2, PDLIM3, COPZ2, ALDH1B1, ANTXR1, GUF1, and SENP6 are negatively correlated with the prognosis of thyroid cancer. The expression of ANTXR1, GUF1, and PDLIM3 was weakly associated with thyroid cancer's immune and molecular subtypes.

CAPN8 involves with exhausted, inflamed, and desert immune microenvironment to influence the metastasis of thyroid cancer

BACKGROUND

Thyroid cancer (THCA) is the most prevalent malignant disease of the endocrine system, in which 5-year survival can attain about 95%, but patients with metastasis have a poor prognosis. Very little is known about the role of CAPN8 in the metastasis of THCA. In particular, the effect of CAPN8 on the tumor immune microenvironment (TIME) and immunotherapy response is unclear.

MATERIAL AND METHODS

Multiome datasets and multiple cohorts were acquired for analysis. Firstly, the expression and the prognostic value of CAPN8 were explored in public datasets and in vitro tumor tissues. Then, hierarchical clustering analysis was performed to identify the immune subtypes of THCA according to the expression of CAPN8 and the activities of related pathways. Subsequent analyses explored the different patterns of TIME, genetic alteration, DNA replication stress, drug sensitivity, and immunotherapy response among the three immune phenotypes. Finally, five individual cohorts of thyroid cancer were utilized to test the robustness and extrapolation of the three immune clusters.

RESULTS

CAPN8 was found to be a significant risk factor for THCA with a markedly elevated level of mRNA and protein in tumor tissues. This potential oncogene could induce the activation of epithelial-mesenchymal transition and E2F-targeted pathways. Three subtypes were identified for THCA, including immune exhausted, inflamed, and immune desert phenotypes. The exhausted type was characterized by a markedly increased expression of inhibitory receptors and infiltration of immune cells but was much more likely to respond to immunotherapy. The immune desert type was resistant to common chemotherapeutics with extensive genomic mutation and copy number variance.

CONCLUSION

The present study firstly explored the role of CAPN8 in the metastasis of THCA from the aspects of TIME. Three immune subtypes were identified with quite different patterns of prognosis, immunotherapy response, and drug sensitivity, providing novel insights for the treatment of THCA and helping understand the cross-talk between CAPN8 and tumor immune microenvironment.

BRAFV600E Expression in Thyrocytes Causes Recruitment of Immunosuppressive STABILIN-1 Macrophages

Simple Summary

Incidence of thyroid cancer, including papillary thyroid cancer, is rapidly increasing. Oncogenes, such as the BRAF^V600E, have been identified, and their effect on thyroid cancer cells have been studied in vitro and in mouse models. What is less understood is the impact of these mutations on thyroid cancer microenvironment and, in turn, the effect of changes in the microenvironment on tumor progression. We investigated the modifications in the cellular composition of thyroid cancer microenvironment using an inducible mouse model. We focused on a subpopulation of macrophages, expressing the STABILIN-1 protein, recruited in the thyroid tumor microenvironment following BRAF^V600E expression. CRISPR/Cas9 genetic inactivation of Stablin-1 did not change macrophage recruitment but highlighted the immunosuppressive role of STABILIN-1-expressing macrophages. The identification of a similar subpopulation of STABILIN-1 macrophages in human thyroid diseases supports a conserved role for these macrophages and offers an opportunity for intervention.

Abstract

Papillary thyroid carcinoma (PTC) is the most frequent histological subtype of thyroid cancers (TC), and BRAF^V600E genetic alteration is found in 60% of this endocrine cancer. This oncogene is associated with poor prognosis, resistance to radioiodine therapy, and tumor progression. Histological follow-up by anatomo-pathologists revealed that two-thirds of surgically-removed thyroids do not present malignant lesions. Thus, continued fundamental research into the molecular mechanisms of TC downstream of BRAF^V600E remains central to better understanding the clinical behavior of these tumors. To study PTC, we used a mouse model in which expression of BRAF^V600E was specifically switched on in thyrocytes by doxycycline administration. Upon daily intraperitoneal doxycycline injection, thyroid tissue rapidly acquired histological features mimicking human PTC. Transcriptomic analysis revealed major changes in immune signaling pathways upon BRAF^V600E induction. Multiplex immunofluorescence confirmed the abundant recruitment of macrophages, among which a population of LYVE-1+/CD206+/STABILIN-1+ was dramatically increased. By genetically inactivating the gene coding for the scavenger receptor STABILIN-1, we showed an increase of CD8+ T cells in this in situ BRAF^V600E-dependent TC. Lastly, we demonstrated the presence of CD206+/STABILIN-1+ macrophages in human thyroid pathologies. Altogether, we revealed the recruitment of immunosuppressive STABILIN-1 macrophages in a PTC mouse model and the interest to further study this macrophage subpopulation in human thyroid tissues.

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.

Roles and new Insights of Macrophages in the Tumor Microenvironment of Thyroid Cancer

Although most thyroid cancers have a good and predictable prognosis, the anaplastic, medullary, and refractory thyroid cancers still prone to recurrence and metastasis, resulting in poor prognosis. Although a number of newly developed targeted therapies have begun to be indicated for the above types of thyroid cancer in recent years, their ability to improve overall survival remain hindered by low efficacy. As the largest component of immune cells in tumor microenvironment, tumor-associated macrophages play a key role in the invasion and metastasis of thyroid cancer. There is much evidence that the immune system, tumor microenvironment and cancer stem cell interactions may revolutionize traditional therapeutic directions. Tumor-associated macrophages have been extensively studied in a variety of tumors, however, research on the relationship between thyroid cancer and macrophages is still insufficient. In this review, we summarize the functions of tumor-associated macrophages in different types of thyroid cancer, their cytokines or chemokines effect on thyroid cancer and the mechanisms that promote tumor proliferation and migration. In addition, we discuss the mechanisms by which tumor-associated macrophages maintain the stemness of thyroid cancer and potential strategies for targeting tumor-associated macrophages to treat thyroid cancer.

RNF185 antisense RNA 1 (RNF185-AS1) promotes proliferation, migration, and invasion in papillary thyroid carcinoma

Long noncoding RNA (lncRNA) plays an important role in multiple cancers. So far, the exact function of lncRNAs in papillary thyroid carcinoma (PTC) is unclear. The purposes of this work were to investigate the function and underlying mechanisms of RNF185 antisense RNA 1 (RNF185-AS1) in PTC. The expression of RNF185-AS1 was analyzed by quantitative real-time PCR (qRT-PCR). Colony formation, 5-ethynyl-2'-deoxyuridine, and Cell Counting Kit-8 assays were utilized to determine cell proliferation. Cell migration and invasion were tested using wound healing and transwell assays. A mouse transplantation tumor model was used for tumor growth analyses in vivo. The regulation of RNF185-AS1 on the downstream miR-429/lipoprotein receptor-related protein (LRP4) axis was predicted and identified through bioinformatic analysis, dual-luciferase reporter assay, and RNA immunoprecipitation (RIP) assay. RNF185-AS1 was dramatically overexpressed in PTC tumors and cells. High RNF185-AS1 expression was associated with bigger tumor size, lymph node metastasis, and advanced tumor-node-metastasis stage in PTC patients. Silencing of RNF185-AS1 impeded the proliferation, migration, and invasion in vitro and constrained tumorigenesis in vivo. Mechanistically, RNF185-AS1 could act as a sponge of miR-429 to regulate the expression of LRP4. In addition, downregulation of miR-429 or upregulation of LRP4 could relieve the proliferation, migration, and invasion of IHH-4 and TPC-1 cells that inhibited by RNF185-AS1 knockdown. Downregulation of RNF185-AS1 may suppress PTC progression through functioning as a sponge of miR-429 to hinder the expression of LRP4. The RNF185-AS1/miR-429/LRP4 axis will lay the groundwork for future therapeutic strategies in PTC.

Advances in pharmacotherapy for advanced thyroid cancer of follicular origin (PTC, FTC). New approved drugs and future therapies

INTRODUCTION

The most common altered signaling found in aggressive iodine-refractory Thyroid cancer derived from follicular cells (RAI-TC) are RTK, MAPK, PI3K, WNT, BRAF, RAS, RET, and TP53. Tyrosine Kinase Inhibitors (TKI) are multi-kinase inhibitors able to act against different pathways, that elicit an anti-neoplastic activity.

AREAS COVERED

The aim of this paper is to review recent novel molecular therapies of RAI-TC. Recently, sorafenib and lenvatinib, have been approved for the treatment of aggressive RAI-TC. Other studies are evaluating vandetanib and selumetinib in RAI-TC. Furthermore, preliminary studies have evaluated dabrafenib, and vemurafenib in BRAF mutated RAI-TC patients to re-induce 131-iodine uptake. The interplay between cells of the immune system and cancer cells can be altered by immune checkpoints inhibitors. The expression of PDL1 in RAI-TC was related to tumor recurrence and poor survival. Several clinical trials are investigating a combination of different therapies, such as lenvatinib and pembrolizumab.

EXPERT OPINION

Mechanisms of resistance to TKIs inhibitors can be of intrinsic or acquired origin. An acquired resistance to lenvatinib, or sorafenib can be due to upregulation of FGFR; therefore anti-FGFR agents are evaluated. A new strategy is to combine TKIs with immunotherapy. Several studies are evaluating lenvatinib and pembrolizumab in RAI-TC patients.

Dynamic Cancer Cell Heterogeneity: Diagnostic and Therapeutic Implications

Though heterogeneity of cancers is recognized and has been much discussed in recent years, the concept often remains overlooked in different routine examinations. Indeed, in clinical or biological articles, reviews, and textbooks, cancers and cancer cells are generally presented as evolving distinct entities rather than as an independent heterogeneous cooperative cell population with its self-oriented biology. There are, therefore, conceptual gaps which can mislead the interpretations/diagnostic and therapeutic approaches. In this short review, we wish to summarize and discuss various aspects of this dynamic evolving heterogeneity and its biological, pathological, clinical, diagnostic, and therapeutic implications, using thyroid carcinoma as an illustrative example.

Integrated analysis of fibroblasts molecular features in papillary thyroid cancer combining single-cell and bulk RNA sequencing technology

BACKGROUND

Papillary thyroid cancer (PTC) is the most common pathological type of thyroid cancer with a high incidence globally. Increasing evidence reported that fibroblasts infiltration in cancer was correlated with prognostic outcomes. However, fibroblasts related study in thyroid cancer remains deficient.

METHODS

Single-cell sequencing data of PTC were analyzed by Seurat R package to explore the ecosystem in PTC and identify fibroblasts cluster. The expression profiles and prognostic values of fibroblast related genes were assessed in TCGA dataset. A fibrosis score model was established for prognosis prediction in thyroid cancer patients. Differentially expressed genes and functional enrichment between high and low fibrosis score groups in TCGA dataset were screened. The correlation of immune cells infiltration and fibrosis score in thyroid cancer patients was explored. Expression levels and prognostic values of key fibroblast related factor were validated in clinical tissues another PTC cohort.

RESULTS

Fibroblasts were highly infiltrated in PTC and could interact with other type of cells by single-cell data analysis. 34 fibroblast related terms were differentially expressed in thyroid tumor tissues. COX regression analysis suggested that the constructed fibrosis score model was an independent prognostic predictor for thyroid cancer patients (HR = 5.17, 95%CI 2.31-11.56, P = 6.36E-05). Patients with low fibrosis scores were associated with a significantly better overall survival (OS) than those with high fibrosis scores in TCGA dataset (P = 7.659E-04). Specific immune cells infiltration levels were positively correlated with fibrosis score, including monocytes, M1 macrophages and eosinophils.

CONCLUSION

Our research demonstrated a comprehensive horizon of fibroblasts features in thyroid cancer microenvironment, which may provide potential value for thyroid cancer treatment.