Leveraging the immune system to treat advanced thyroid cancers

Prognostic significance of the pan-immune-inflammation value (PIV) in patients with differentiated thyroid carcinoma

OBJECTIVE

The pan-immune-inflammation value (PIV) is a novel inflammatory biomarker for evaluating inflammatory status in patients with cancer. The aim of this study was to evaluate the prognostic value of PIV in patients with differentiated thyroid cancers (DTCs).

SUBJECTS AND METHODS

The study included 376 patients with DTC who underwent curative resection. The PIV was calculated using the formula (neutrophils × monocytes × platelets)/lymphocytes. The TNM stages 3-4 were considered advanced. Patients were also categorized into low-, intermediate-, and high-risk groups according to the AmericanThyroid Association (ATA) risk classification system. Demographic, laboratory, and clinicopathological data were obtained from the patients' files. The predictive value of PIV on TNM advanced stage, ATA high-risk category, and distant metastases was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

The optimal PIV values for predicting TNM advanced stage, ATA high-risk category, and distant metastases were, respectively, 331.62 (area under the curve [AUC] 0.730, sensitivity 66.7%, specificity 64.8%), 365.52 (AUC 0.822, sensitivity 79.5%, specificity 76.9%), and 357.65 (AUC 0.774, sensitivity 75.2%, specificity 72%). On regression analysis, PIV ≥ 365.52 (odds ratio [OR] 29.150, 95% confidence interval [CI] 8.148-104.290, p < 0.001) and PIV ≥ 357.65 (OR 7.224, 95% CI 1.700-30.693, p = 0.007) emerged as independent risk factors for ATA high-risk category and distant metastases, respectively.

CONCLUSION

Among patients with DTC, PIV is an independent risk factor for distant metastases and ATA high-risk category. While this finding must be supported by more comprehensive studies, PIV has the potential to be used as a prognostic biomarker in these patients.

KLK7, KLK10, and KLK11 in Papillary Thyroid Cancer: Bioinformatic Analysis and Experimental Validation

Despite many studies on papillary thyroid carcinoma (PTC) in the past few decades, some critical and significant genes remain undiscovered. To explore genes that may play crucial roles in PTC, a detailed analysis of the expression levels, mutations, and clinical significance of Kallikrein-related peptidases (KLKs) family genes in PTC was undertaken to provide new targets for the precise treatment of the disease. A comprehensive analysis of KLK family genes was performed using various online tools, such as GEPIA, Kaplan-Meier Plotter, LinkedOmics, GSCA, TIMER, and Cluego. KLK7, KLK10, and KLK11 were critical factors of KLK family genes. Then, functional assays were carried out on KLK7/10/11 to determine their proliferation, migration, and invasion capabilities in PTC. The mRNA expression levels of KLK7, KLK10, KLK11, and KLK13 were significantly elevated in thyroid carcinoma, while KLK1, KLK2, KLK3 and KLK4 mRNA levels were decreased compared to normal tissues. Correlations between KLK2/7-12/15 expression levels and tumor stage were also observed in thyroid carcinoma. Survival analysis demonstrated that KLK4/5/7/9-12/14 was associated with overall survival in patients with thyroid cancer. Not only were KLK genes strongly associated with cancer-related pathways, but also KLK7/10/11 was associated with immune-cell infiltration. Finally, silencing KLK7/10/11 impaired human papillary thyroid carcinoma cells' growth, migration ability, and invasiveness. The increased expression of KLK7, KLK10, and KLK11 may serve as molecular markers to identify PTC patients. KLK7, KLK10, and KLK11 could be potential prognostic indicators and targets for precision therapy against PTC.

PD-L1 Expression Varies in Thyroid Cancer Types and Is Associated with Decreased Progression Free Survival (PFS) in Patients with Anaplastic Thyroid Cancer

BACKGROUND

Thyroid cancer (TC) remains a significant clinical challenge worldwide, with a subset of patients facing aggressive disease progression and therapeutic resistance. Immune checkpoint inhibitors targeting programmed death-ligand 1 (PD-L1) have emerged as promising therapeutic approaches for various malignancies, yet their efficacy in TC remains uncertain. The objective of this study was to investigate PD-L1 expression in aggressive TC and its association with histological subtypes, molecular mutation, and progression-free survival.

METHODS

This is a retrospective study of patients with advanced TC seen in two tertiary health care centers. Included in this study were patients with advanced TC with recurrence or progression on therapy for whom tumor molecular profiling and PD-L1 status were available. Kaplan-Meier estimators were utilized to analyze the progression-free survival (PFS) between patients with PD-L1 positive and negative status in Anaplastic TC (ATC) subgroup.

RESULTS

A total of 176 patients with advanced thyroid cancer were included (48.9% female). Of the patients, 13 had ATC, 11 Medullary TC (MTC), 81 Papillary TC Classic Variant (PTCCV), 20 Follicular TC (FTC), 8 Oncocytic TC (OTC), 10 Poorly Differentiated TC (PDTC), and 30 had the Papillary TC Follicular Variant (PTCFV). BRAF mutation was present in 41%, TERT in 30%, RAS in 19%, TP53 in 10%, and RET in 8.6% of patients. PD-L1 positivity was significantly different across different TC types and histological subtypes (p < 0.01): Patients with OTC had the highest frequency of PD-L1 positivity (71%), followed by ATC (69%), PTCCV (28.5%), and FTC (11%). Patients with MTC and PTCFV did not exhibit any PD-L1 positivity. TP53 mutation was positively associated with PD-L1 expression (21.6% vs. 7.5%, p = 0.03), and RAS mutation was negatively associated with PD-L1 expression (8.1% vs. 24.2% p = 0.04). Among patients with ATC, positive PD-L1 expression was associated with lower PFS (p = 0.002).

CONCLUSIONS

PD-L1 expression varies across different TC types and histological subtypes and may be modulated by the mutational landscape. PD-L1 expression in ATC is associated with shorter PFS. Follow up studies are warranted to elucidate the molecular mechanism driving the observed differences in immune pathways, potentially paving the way for the development of more effective and personalized immune therapies for patients with aggressive TC.

Cabozantinib in combination with immune checkpoint inhibitors for renal cell carcinoma: a systematic review and meta-analysis

Context

Cabozantinib combined with immune checkpoint inhibitors (ICIs) has brought a new therapeutic effect for the medical treatment of renal cell carcinoma (RCC).

Objectives

We performed a meta-analysis of randomized controlled trials and single-arm trials to evaluate the efficacy and safety of cabozantinib plus ICIs in RCC.

Methods

We extracted data from PubMed, Cochrane, Medline and Embase databases, and rated literature quality through Cochrane risk of bias tool and MINORS. RevMan5.3 software was used to analyze the results of randomized controlled trials and single-arm trials.

Results

A total of 7 studies were included. Treatment with cabozantinib plus ICIs improved PFS [HR 0.75, (95%CI: 0.52, 1.08), p = 0.12] and the OS [HR 0.80, (95%CI: 0.60, 1.07), p = 0.13] in randomized controlled trials. Meanwhile, the result of the ORR in randomized controlled trials was [risk ratio (RR) 1.37, (95%CI: 1.21, 1.54), p < 0.00001] and in single-arm trials was [risk difference (RD) 0.49, (95%CI: 0.26, 0.71), p < 0.0001].

Conclusion

Cabozantinib plus ICIs prolonged the PFS and OS, and improved ORR in patients with RCC. Our recommendation is to use cabozantinib plus ICIs to treat advanced RCC, and to continuous monitor and manage the drug-related adverse events.

Systematic Review Registration

identifier CRD42023455878.

Prognostic Roles of Inflammatory Biomarkers in Radioiodine-Refractory Thyroid Cancer Treated with Lenvatinib

BACKGRUOUND

Inflammatory biomarkers, such as the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR), serve as valuable prognostic indicators in various cancers. This multicenter, retrospective cohort study assessed the treatment outcomes of lenvatinib in 71 patients with radioactive iodine (RAI)-refractory thyroid cancer, considering the baseline inflammatory biomarkers.

METHODS

This study retrospectively included patients from five tertiary hospitals in Korea whose complete blood counts were available before lenvatinib treatment. Progression-free survival (PFS) and overall survival (OS) were evaluated based on the median value of inflammatory biomarkers.

RESULTS

No significant differences in baseline characteristics were observed among patients grouped according to the inflammatory biomarkers, except for older patients with a higher-than-median NLR (≥2) compared to their counterparts with a lower NLR (P= 0.01). Patients with a higher-than-median NLR had significantly shorter PFS (P=0.02) and OS (P=0.017) than those with a lower NLR. In multivariate analysis, a higher-than-median NLR was significantly associated with poor OS (hazard ratio, 3.0; 95% confidence interval, 1.24 to 7.29; P=0.015). However, neither the LMR nor the PLR was associated with PFS. A higher-than-median LMR (≥3.9) was significantly associated with prolonged OS compared to a lower LMR (P=0.036). In contrast, a higher-than-median PLR (≥142.1) was associated with shorter OS compared to a lower PLR (P=0.039).

CONCLUSION

Baseline inflammatory biomarkers can serve as predictive indicators of PFS and OS in patients with RAI-refractory thyroid cancer treated with lenvatinib.

Spatial transcriptomics reveals prognosis-associated cellular heterogeneity in the papillary thyroid carcinoma microenvironment

BACKGROUND

Papillary thyroid carcinoma (PTC) is the most common malignant endocrine tumour, and its incidence and prevalence are increasing considerably. Cellular heterogeneity in the tumour microenvironment is important for PTC prognosis. Spatial transcriptomics is a powerful technique for cellular heterogeneity study.

METHODS

In conjunction with a clinical pathologist identification method, spatial transcriptomics was employed to characterise the spatial location and RNA profiles of PTC-associated cells within the tissue sections. The spatial RNA-clinical signature genes for each cell type were extracted and applied to outlining the distribution regions of specific cells on the entire section. The cellular heterogeneity of each cell type was further revealed by ContourPlot analysis, monocle analysis, trajectory analysis, ligand-receptor analysis and Gene Ontology enrichment analysis.

RESULTS

The spatial distribution region of tumour cells, typical and atypical follicular cells (FCs and AFCs) and immune cells were accurately and comprehensively identified in all five PTC tissue sections. AFCs were identified as a transitional state between FCs and tumour cells, exhibiting a higher resemblance to the latter. Three tumour foci were shared among all patients out of the 13 observed. Notably, tumour foci No. 2 displayed elevated expression levels of genes associated with lower relapse-free survival in PTC patients. We discovered key ligand-receptor interactions, including LAMB3-ITGA2, FN1-ITGA3 and FN1-SDC4, involved in the transition of PTC cells from FCs to AFCs and eventually to tumour cells. High expression of these patterns correlated with reduced relapse-free survival. In the tumour immune microenvironment, reduced interaction between myeloid-derived TGFB1 and TGFBR1 in tumour focus No. 2 contributed to tumourigenesis and increased heterogeneity. The spatial RNA-clinical analysis method developed here revealed prognosis-associated cellular heterogeneity in the PTC microenvironment.

CONCLUSIONS

The occurrence of tumour foci No. 2 and three enhanced ligand-receptor interactions in the AFC area/tumour foci reduced the relapse-free survival of PTC patients, potentially leading to improved prognostic strategies and targeted therapies for PTC patients.

Preoperative systemic inflammatory markers as prognostic factors in differentiated thyroid cancer: a systematic review and meta-analysis

BACKGROUND

Inflammation has been associated with tumor development and circulating inflammatory biomarkers have been proposed as possible predictors of recurrence of several solid tumors. However, the role of inflammation markers in differentiated thyroid carcinoma (DTC) is still uncertain.

OBJECTIVE

This meta-analysis aimed to assess the prognostic value of neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) in patients with DTC.

METHODS

Studies investigating the association between survival and preoperative circulating inflammatory markers in DTC patients were included. The primary outcome was disease-free survival (DFS). Cumulative logarithms of the hazard ratio (log-HRs) with 95% CI were calculated through the inverse variance method using a random-effects model.

RESULTS

A total of 7599 patients with a mean age of 48.89 (95% CI 44.16-53.63) were included. The estimated pooled log-HRs for DFS were 0.07 for NLR (95% CI -0.12-0.26; p = 0.43), -0.58 for LMR (95% CI -1.21-0.05; p = 0.06), and 0.01 (95% CI 0-0.01; p = 0.21) for PLR.

CONCLUSIONS

Our meta-analysis showed no association between NLR, PLR, LMR and DFS in DTC; however, more prospective data are needed to better define the association between inflammatory status and prognosis of DTC.

METTL3 inhibition induced by M2 macrophage-derived extracellular vesicles drives anti-PD-1 therapy resistance via M6A-CD70-mediated immune suppression in thyroid cancer

The treatment options for advanced papillary thyroid cancer (PTC) and anaplastic thyroid cancer (ATC) refractory to standard therapies are limited. Although anti-PD-1 therapy has a manageable safety profile and has been effective in a small percentage of patients with advanced PTC and refractory ATC, the majority of the patients either do not respond or develop resistance to anti-PD-1 therapy. N6-methyladenosine (m6A) modification is a critical determinant of the complexity of the tumor microenvironment (TME). However, it is unclear whether and how m6A modification in tumor cells shapes the immune landscape of PTC and ATC. In this study, we performed bulk and single cell RNA sequencing analysis of PTC and ATC tissues, and found that low METTL3 expression not only correlated to poor response to immune checkpoint blockade (ICB) but was also associated with increased TNF family-related ligand-receptor interactions in the immunosuppressive Tregs and exhausted T cells. Furthermore, overexpression of METTL3 in PTC and ATC cells enhanced the efficacy of anti-PD-1 therapy in a peripheral blood mononuclear cell humanized NCG (huPBMC-NCG) mouse model. Mechanistically, M2 macrophage-derived extracellular vesicles (M2 EVs) inhibited METTL3 expression in PTC and ATC cells via miR-21-5p. Downregulation of METTL3 promoted demethylation of CD70 mRNA, which prevented YTHDF2-mediated degradation of the transcripts. The stabilization of CD70 mRNA, and the subsequent upregulation in CD70 protein levels increased the abundance of the immunosuppressive Tregs and terminally exhausted T cells, thereby inducing resistance to anti-PD-1 therapy. Furthermore, blocking CD70 using cusatuzumab, a high-affinity monoclonal antibody, reversed the anti-PD-1 therapy resistance induced by M2 EVs in vivo. Finally, we demonstrated that METTL3 expression negatively correlated with CD70 expression and M2 macrophages and Tregs infiltration in PTC and ATC tissues. Our findings provide new insights into developing novel therapies for advanced PTC and ATC.

Immunotherapy or targeted therapy: What will be the future treatment for anaplastic thyroid carcinoma?

Anaplastic thyroid carcinoma (ATC) is a rare and aggressive form of thyroid carcinoma (TC). Currently, there are no effective treatments for this condition. In the past few years, targeted therapy and immunotherapy have made significant progress in ATC treatment. Several common genetic mutations have been found in ATC cells, involving different molecular pathways related to tumor progression, and new therapies that act on these molecular pathways have been studied to improve the quality of life of these patients. In 2018, the FDA approved dabrafenib combined with trametinib to treat BRAF-positive ATC, confirming its therapeutic potential. At the same time, the recent emergence of immunotherapy has also attracted wide attention from researchers. While immunotherapy for ATC is still in the experimental stage, numerous studies have shown that immunotherapy is a potential therapy for ATC. In addition, it has also been found that the combination of immunotherapy and targeted therapy may enhance the anti-tumor effect of targeted therapy. In recent years, there has been some progress in the study of targeted therapy or immunotherapy combined with radiotherapy or chemotherapy, showing the prospect of combined therapy in ATC. In this review, we analyze the response mechanism and potential effects of targeted therapy, immunotherapy, and combination therapy in ATC treatment and explore the future of treatment for ATC.

Inflammatory biomarkers predict outcomes of patients with radioactive iodine refractory thyroid cancer treated with sorafenib

BACKGROUND

The objective of this multicenter, retrospective cohort study was to evaluate the ability of inflammatory biomarkers representing the host immune system to predict outcomes in 70 patients with progressive radioactive iodine (RAI)-refractory thyroid cancer who were treated with sorafenib.

METHOD

Patients were divided into low and high inflammatory biomarker groups based on median values. Progression-free survival (PFS) and overall survival (OS) were assessed based on the lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR).

RESULTS

The median LMR, NLR, and PLR values were 3.4, 2.2, and 140.1, respectively. No significant differences were observed in baseline characteristics of high and low LMR, NLR and PLR groups. Median PFS values were 6.6 and 19.5 months in the low and high LMR groups, respectively (P < 0.001). Compared with the high NLR and PLR groups, PFS was significantly prolonged in the low NLR and PLR groups (P = 0.003 and P = 0.041 respectively). In the multivariate analysis, low LMR and high NLR were associated with poor PFS after adjusting for multiple confounding factors including age, sex, pathology, disease-related symptoms, serum thyroglobulin level, lung-only metastasis, cumulative RAI dose, time from diagnosis, and longer diameter of the target lesion (hazard ratio, HR = 2.42; 95% confidence interval, CI 1.25-4.71; P = 0.009, and HR = 2.09; CI, 1.06-4.14; P = 0.033, respectively). High LMR, low NLR, and low PLR were significantly associated with prolonged OS (P = 0.011, P = 0.023, and P = 0.007, respectively). Patients with at least one risk factors for inflammatory biomarkers presented a significantly lower PFS (HR 2.29; CI, 1.36-3.84; P = 0.003) and OS (HR 2.95; CI, 1.49-5.81; P = 0.006) than patients without any risk factor.

CONCLUSION

Baseline inflammatory biomarkers successfully predicted PFS and OS in patients with progressive RAI-refractory thyroid cancer treated with sorafenib. These prognostic biomarkers might help arrive at appropriate clinical decisions regarding the use of sorafenib.

Influence of Lenvatinib on the Functional Reprogramming of Peripheral Myeloid Cells in the Context of Non-Medullary Thyroid Carcinoma

Lenvatinib is a multitarget tyrosine kinase inhibitor (TKI) approved for the treatment of several types of cancers, including metastatic differentiated thyroid cancer (DTC). The intended targets include VEGFR 1-3, FGFR 1-4, PDGFRα, RET, and KIT signaling pathways, but drug resistance inevitably develops and a complete cure is very rare. Recent data has revealed that most of the TKIs have additional 'off-target' immunological effects, which might contribute to a protective antitumor immune response; however, human cellular data are lacking regarding Lenvatinib-mediated immunomodulation in DTC. Here, we investigated in ex vivo models the impact of Lenvatinib on the function of immune cells in healthy volunteers. We found that monocytes and macrophages were particularly susceptible to Lenvatinib, while neutrophiles and lymphocytes were less affected. In tumor-immune cell co-culture experiments, Lenvatinib exerted a broad inhibitory effect on the proinflammatory response in TC-induced macrophages. Interestingly, Lenvatinib-treated cells had decreased cellular M2 membrane markers, whereas they secreted a significantly higher level of the anti-inflammatory cytokine IL-10 upon LPS stimulation. In addition, prolonged exposure to Lenvatinib impaired macrophages survival and phenotypical differentiation, which was accompanied by remarkable morphological changes and suppressed cellular metabolic activity. These effects were mediated by myeloid cell-intrinsic mechanisms which are independent of Lenvatinib's on-target activity. Finally, using specific inhibitors, we argue that dual effects on p38 MAPK and Syk pathways are likely the underlying mechanism of the off-target immunological effects we observed in this study. Collectively, our data show the immunomodulatory properties of Lenvatinib on human monocytes. These insights could be harnessed for the future design of novel treatment strategies involving a combination of Lenvatinib with other immunotherapeutic agents.

IL2RA+VSIG4+ tumor-associated macrophage is a key subpopulation of the immunosuppressive microenvironment in anaplastic thyroid cancer

Extensive infiltration of tumor-associated macrophages was correlated poor prognosis in anaplastic thyroid cancer (ATC). However, the heterogeneity and characteristics of the ATC-associated macrophages (ATAMs) in ATC remain far from clear. We combined single-cell RNA-sequencing analysis and gene expression microarray datasets to assess the molecular signature of ATAMs. Compared with normal thyroid-associated macrophages (NTAMs), 778 differentially expressed genes (DEGs) significantly changed in ATAMs compared with NTAMs. These DEGs were correlated with oxidative phosphorylation (M2 phenotype) and phagocytosis (M1 phenotype). Moreover, ATAMs highly expressed pro-tumor genes associated with angiogenesis, fibrosis, metalloprotease activity, and metastasis. Notably, we identified one ATC-specific subset, IL2RA⁺ VSIG4⁺ ATAMs, co-expressed M1 and M2 markers. The infiltration of IL2RA⁺ VSIG4⁺ ATAMs showed strong correlation with BRAF and RAS signaling, and its high infiltration was associated with favorable prognosis in thyroid-cancer patients. IL2RA⁺ VSIG4⁺ ATAMs were associated with increased tumor-infiltrating lymphocytes (B cells, CD8⁺ T cells, Tregs). IL2RA⁺ VSIG4⁺ ATAMs interacted with CD8⁺ T cells and Tregs through immune checkpoints (such as LGALS9_HAVCR2), cytokines (such as CXCL10_CXCR3), and receptors (such as CSF1R_CSF1), thereby forming an immunosuppressive microenvironment. Multiplex immunohistochemistry staining and coculture experiment confirmed that ATC cancer cells were able to induce the polarization of IL2RA⁺ VSIG4⁺ ATAMs. Besides, we identified several novel ATC-specific immune checkpoint genes including the immunosuppressive molecule VSIG4, LAIR1, and LILRB2. Expression of VSIG4 was also significantly correlated with tumor-infiltrating lymphocytes (B cells, CD8⁺ T cells, Tregs). In conclusion, our study revealed an ATC-specific ATAM subset with bifunctional phenotype, which provided a comprehensive insight to delineate the molecular characteristics of ATC-associated macrophages.

Indoleamine 2,3-dioxygenase 2 immunohistochemical expression in medullary thyroid carcinoma: implications in prognosis and immunomodulatory effects

BACKGROUND

The linkage between IDO2 expression and cancer progression is still unclear, particularly in medullary thyroid carcinoma (MTC). Our purpose is to unveil the potential correlations between IDO2 status, clinical-pathological parameters, patients' prognosis, and the possible immunomodulatory functions in MTC.

METHODS

Immunohistochemical expression levels of IDO2 were evaluated in the resected MTC surgical specimens and corresponding lymph nodes. CD4 + T cell infiltration was also evaluated by immunohistochemical analysis in the MTC tissues. The association of the IDO2 expression level with clinicopathologic characteristics, overall survival (OS)/recurrence-free survival (RFS), and CD4 + T cell infiltration were retrospectively investigated.

RESULTS

High expression of IDO2 is closely associated with more aggressive clinicopathological features, such as multifocality, ETE, a higher pT stage and especially a higher pN stage. Moreover, a significant difference in RFS was observed between the IDO2-high and IDO2-low groups. IDO2 expression of lymph node tissues was significantly related to the metastasis status. Furthermore, we found that IDO2 expression is negatively correlated with CD4 + T cell infiltrations in MTC tissues.

CONCLUSION

The expression level of IDO2 is associated with aggressive characteristics and is predictive of poor prognosis in patients with MTC. Also, an interesting observation is that IDO2 involvement in MTC showed a moderate sexual dimorphism, of which female patients tend to be more affected by IDO2 status. Moreover, our results showed the potential immunomodulatory functions of IDO2. The close relationship between IDO2 and CD4 + T cell infiltration in the MTC microenvironment, together with its potential prognostic implications, makes it possible for IDO2 to serve as an alternative drug target in cancer immunotherapy and as a new prognostic tool.

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.

Clinical Significance of the Expression of Co-Stimulatory Molecule B7-H3 in Papillary Thyroid Carcinoma

Background: B7-H3, also known as CD276, an important immune checkpoint member of the B7-CD28 family, is confirmed as a promising target after PD-L1 in clinical trials. Although the overexpression of B7-H3 has been associated with invasive metastatic potential and poor prognosis in multiple types of cancer, nothing is known regarding the expression profiles of B7-H3 in papillary thyroid carcinoma (PTC). In this study, we carried out a large-scale analysis of B7-H3 expression in PTC patients and evaluated the potential clinical significance of B7-H3.

Methods: In total, data from 1,210 samples, including 867 cases from TCGA and four GEO datasets, were collected for B7-H3–related transcriptome analyses, and 343 postoperative, whole-tumor sections were collected from patients with PTC at our institute for B7-H3–specific immunohistochemistry (IHC) staining. The statistical analysis was primarily accomplished using the R project for statistical computing.

Results: B7-H3 positivity was found in 84.8% of PTC patients (291/343), and the mRNA and protein expression levels of B7-H3 in PTC were markedly higher than those of para-tumor tissues (p < 0.001), demonstrating that B7-H3 can serve as a potential diagnostic biomarker for PTC. The significant upregulation of B7-H3 in PTC is caused by distinct patterns of CNVs and CpG DNA methylation. Functional enrichment analysis confirmed that high B7-H3 expression was significantly associated with specific immune features and angiogenesis. High B7-H3 protein expression was associated with tumor size (p = 0.022), extrathyroidal extension (ETE) (p = 0.003), and lymph node metastasis (LNM) (p < 0.001). More importantly, multivariate analysis confirmed that B7-H3 was an independent predictor of relapse-free survival (RFS) (p < 0.05). In the subgroup analysis, positive B7-H3 staining was associated with worse RFS in patients with primary tumor size ≥2 cm (p < 0.05), age ≥55 years (p < 0.05), LNM (p = 0.07), multifocality (p < 0.05), and ETE (p < 0.05). In addition, Circos plots indicated that B7-H3 was significantly associated with other immune checkpoints in the B7-CD28 family.

Conclusion: This is the first comprehensive study to elucidate the expression profile of B7-H3 in PTC. Our observations revealed that B7-H3 is a novel independent biomarker for predicting LNM and disease recurrence for PTC patients, and it thus may serve as an indicator that could be used to improve risk-adapted therapeutic strategies and a novel target for immunotherapy strategies for patients who undergo an aggressive disease course.

Comprehensive Analysis of the Prognosis and Drug Sensitivity of Differentiation-Related lncRNAs in Papillary Thyroid Cancer

Dedifferentiation is the main concern associated with radioactive iodine (RAI) refractoriness in patients with papillary thyroid cancer (PTC), and the underlying mechanisms of PTC dedifferentiation remain unclear. The present work aimed to identify a useful signature to indicate dedifferentiation and further explore its role in prognosis and susceptibility to chemotherapy drugs. A total of five prognostic-related DR-lncRNAs were selected to establish a prognostic-predicting model, and corresponding risk scores were closely associated with the infiltration of immune cells and immune checkpoint blockade. Moreover, we built an integrated nomogram based on DR-lncRNAs and age that showed a strong ability to predict the 3- and 5-year overall survival. Interestingly, drug sensitivity analysis revealed that the low-risk group was more sensitive to Bendamustine and TAS-6417 than the high-risk group. In addition, knockdown of DR-lncRNAs (DPH6-DT) strongly promoted cell proliferation, invasion, and migration via PI3K-AKT signal pathway in vitro. Furthermore, DPH6-DT downregulation also increased the expression of vimentin and N-cadherin during epithelial-mesenchymal transition. This study firstly confirms that DR-lncRNAs play a vital role in the prognosis and immune cells infiltration in patients with PTC, as well as a predictor of the drugs' chemosensitivity. Based on our results, DR-lncRNAs can serve as a promising prognostic biomarkers and treatment targets.

Sex Differences in Differentiated Thyroid Cancer

Background: Sex dimorphism strongly impacts tumor biology, with most cancers having a male predominance. Uniquely, thyroid cancer (TC) is the only nonreproductive cancer with striking female predominance with three- to four-fold higher incidence among females, although males generally have more aggressive disease. The molecular basis for this observation is not known, and current approaches in treatment and surveillance are not sex specific. Summary: Although TC has overall good prognosis, 6-20% of patients develop regional or distant metastasis, one third of whom are not responsive to conventional treatment approaches and suffer a 10-year survival rate of only 10%. More efficacious treatment strategies are needed for these aggressive TCs, as tyrosine kinase inhibitors and immunotherapy have major toxicities without demonstrable overall survival benefit. Emerging evidence indicates a role of sex hormones, genetics, and the immune system in modulation of both risk for TC and its progression in a sex-specific manner. Conclusion: Greater understanding of the molecular mechanisms underlying sex differences in TC pathogenesis could provide insights into the development of sex-specific, targeted, and effective strategies for prevention, diagnosis, and management. This review summarizes emerging evidence for the importance of sex in the pathogenesis, progression, and response to treatment in differentiated TC with emphasis on the role of sex hormones, genetics, and the immune system.

Postoperative external beam radiotherapy for locoregional control in iodine refractory differentiated thyroid cancer

Background

The role of postoperative external beam radiotherapy (EBRT) in patients with residual iodine refractory-differentiated thyroid cancer (IR-DTC) is still inconclusive. The aim of this retrospective study was to evaluate locoregional control (LRC) and overall survival (OS), and potential side effects after postoperative EBRT for both microscopic and macroscopic non-radically resected, locally advanced IR-DTC.

Methods

Between 1990 and 2016, 49 patients with locally advanced IR-DTC received EBRT for microscopic (R1; n = 28) or macroscopic (R2; n = 21) locoregional residual disease. For more insight into the added effect of EBRT, we performed an intrapatient sub-analysis in 32 patients who had undergone more than 1 surgical intervention, comparing LRC after primary, curative-intended surgery with LRC after repeated surgery plus EBRT. To estimate LRC and OS, we used Kaplan-Meier curves. From 2007 onward, we prospectively recorded toxicity data in our head and neck cancer database (n = 10).

Results

LRC rates 5 years after EBRT were higher for R1 (84.3%) than for R2 (44.9%) residual disease (P = 0.016). The 5-year OS rate after EBRT was 72.1% for R1 and 33.1% for R2 disease (P = 0.003). In the intrapatient analysis (n = 32), LRC rates were 6.3% 5 years after only initial surgery and 77.9% after repeated surgery with EBRT (P < 0.001). Acute toxicity was limited to grade I and II xerostomia, mucositis, and hoarseness; only one patient developed late grade III dysphagia.

Conclusions

Postoperative EBRT is associated with long-lasting LRC and OS with acceptable toxicity in patients with locally advanced IR-DTC, especially in microscopic residual disease.

Immunotherapy in anaplastic thyroid cancer: Case series

Unresectable anaplastic thyroid cancer (ATC) has a poor prognosis. Chemotherapy and radiotherapy have limited effects on it. Here, we present four cases who underwent immunotherapy for ATC. The patients were aged between 58 and 70 years. Two male patients with pulmonary metastases received pembrolizumab and lenvatinib. However, they died of septic shock and respiratory failure in 2.7 and 1 months, respectively, after the initiation of combination therapy. Another male patient with stage IVB disease was treated with spartalizumab. The tumor remained stable after surgical debulking but slightly progressed after 23 months. He survived for 45.5 months after spartalizumab initiation. A female patient with BRAF-mutant ATC and lung metastases was treated with a combination of pembrolizumab and lenvatinib, which was complicated with grade 4 transaminitis. The patient subsequently received dabrafenib (a BRAF inhibitor) and trametinib (a MEK inhibitor) treatment, which was continued for 10.2 months with a best response of partial remission. She died 18 months after the initial diagnosis (11.4 months after treatment with dabrafenib and trametinib). In conclusion, the treatment responses of immunotherapy, either alone or in combination with other therapies, were highly variable in patients with ATC and should be carefully monitored along with the side effects.

DIO3OS as a potential biomarker of papillary thyroid cancer

BACKGROUND

Papillary thyroid carcinoma (PTC) is one of the common clinical tumors, where LncRNA plays an important role in tumorigenesis and its development. The purpose of this study was to explore the role of DIO3OS in PTC.

METHOD

Firstly, this study verified the expression of DIO3OS in PTC through the public database. Then, the differences in DIO3OS expression between the PTC group and paracancerous tissues were verified using the qRT-PCR. A series of in vitro experiments were conducted to verify the function of DIO3OS in PTC, while its involvement in possible pathways was analyzed by the GSEA. The ssGSEA algorithm estimated the immune status using the queue transcriptome graph derived from the TCGA database. Further, the correlation analysis was used to confirm the relationship between DIO3OS and the immune genes.

RESULT

The results showed that the expression of DIO3OS was low in PTC. The same results were also confirmed by qRT-PCR analysis (P= 0.0077). In vitro, DIO3OS was localized within the cytoplasm and exosomes. Overexpression of DIO3OS hindered the proliferation, invasion, and migration of PTC cells. According to the degree of immune cell infiltration, the tumor group was divided into high immune cell infiltration group, medium immune cell infiltration group, and low immune cell infiltration group. The results showed that the DIO3OS was highly expressed in the high immune cell infiltration group (P < 0.001), which was positively correlated with the immune cell infiltration and also correlated with multiple immune genes.

CONCLUSION

In summary, this study illustrated the expression pattern of DIO3OS in PTC, which may be involved in the immune-inflammatory pathway. Hence, our results may provide new diagnostic biomarkers and therapeutic targets for PTC.

Percutaneous thermal ablation of lung metastases from thyroid carcinomas. A retrospective multicenter study of 107 nodules. On behalf of the TUTHYREF network

PURPOSE

To determine efficacy and safety of thermal ablation (TA) for the local treatment of lung metastases of thyroid cancer.

METHODS

We retrospectively studied 47 patients from 10 centers treated by TA (radiofrequency, microwaves, and cryoablation) over 10 years. The endpoints were overall survival (OS), local efficacy, complications (CTCAE classification), and factors associated with survival. OS curves after first TA were built using the Kaplan-Meier method and compared with the log-rank test.

RESULTS

A total of 107 lung metastases during 75 sessions were treated by radiofrequency (n = 56), microwaves (n = 9), and cryoablation (n = 10). Median follow-up time after TA was 5.2 years (0.2-13.3). OS was 93% at 2 years (95% confidence interval (CI): 86-94) and 79% at 3 years (95% CI: 66-91). On univariate and multivariate analysis with a Cox model, histology was the only significant factor for OS. OS at 3 years was 94% for follicular, oncocytic, or papillary follicular variant carcinomas, compared to 59% for papillary, medullary, insular or anaplastic carcinomas (P = 0.0001). The local control rate was 98.1% at 1 year and 94.8% at 2, 3, 4, and 5 years. Morbidity was low with no major complications (grade 4 and 5 CTCAE) and no complications in 29 of 75 sessions (38.7%).

CONCLUSIONS

TA is a useful, safe and effective option for local treatment of lung metastases from thyroid carcinoma. Prolonged OS was obtained, especially for lung metastases from follicular, oncocytic, or papillary follicular variant carcinomas. Achieving disease control with TA delays the need for systemic treatment.

Identification of an immune-related signature indicating the dedifferentiation of thyroid cells

Background

Immune cells account for a large proportion of the tumour microenvironment in anaplastic thyroid carcinomas (ATCs). However, the expression pattern of immune-related genes (IRGs) in ATCs is unclear. Our study aimed to identify an immune-related signature indicating the dedifferentiation of thyroid cells.

Methods

We compared the differences in thyroid differentiation score (TDS), infiltration of immune cells and enriched pathways between ATCs and papillary thyroid carcinomas (PTCs) or normal thyroid tissues in the Gene Expression Omnibus database. Univariate and multivariable Cox analyses were used to screen prognosis-associated IRGs in The Cancer Genome Atlas database. After constructing a risk score, we investigated its predictive value for differentiation and survival by applying receiver operating characteristic and Kaplan–Meier curves. We further explored its associations with important immune checkpoint molecules, infiltrating immune cells and response to immunotherapy.

Results

Compared with PTCs or normal thyroid tissues, ATCs exhibited lower TDS values and higher enrichment of immune cells and activation of the inflammatory response. The quantitative analyses and immunohistochemical staining validated that most ATC cell lines and ATC tissues had higher expression of MMP9 and lower expression of SDC2 than normal thyroid samples and PTC. Higher risk scores indicates dedifferentiation and a worse prognosis. Additionally, the risk score was positively correlated with the immune checkpoint molecules PDL1, CTLA4, IDO1, and HAVCR2 and infiltration of multiple immune cells. Importantly, we found that the samples with higher risk scores tended to have a better response to immunotherapy than those with lower scores.

Conclusion

Our findings indicate that the risk score may not only contribute to the determination of differentiation and prognosis of thyroid carcinomas but also help the prediction of immune cells infiltration and immunotherapy response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01939-3.

Prognostic Value of the Neutrophil-to-Lymphocyte Ratio before and after Radiotherapy for Anaplastic Thyroid Carcinoma

Simple Summary

Systemic hematologic markers such as the neutrophil–lymphocyte ratio (NLR) are attracting attention in a simple blood test predicting survival and treatment outcomes in various solid cancers. In our study including 40 patients with anaplastic thyroid cancer (ATC) who underwent radiotherapy, we found that high NLR before and after radiotherapy was associated with poor survival. This study result means that host immunity has an important role in patients with ATC, which can be important information for designing future investigations on the impact of immune system modulating therapy in ATC.

Abstract

The neutrophil–lymphocyte ratio (NLR) is a marker of systemic inflammation, and its elevation has recently been associated with poor survival in many solid cancers. Leukocyte elevation and lymphocyte reduction are associated with a poor response to radiotherapy (RT). This study aimed to assess the prognostic value of NLR before and after RT for anaplastic thyroid carcinoma (ATC). This retrospective study analyzed 40 patients with ATC who received RT with available complete blood cell count data from November 1995 through May 2020 at Samsung Medical Center (Seoul, Korea). Patients were classified into two groups according to the NLR before and after RT. The median overall survival (OS) was 8.9 months (range, 3.5–18.2) in the low NLR group (<3.47) and 5.2 months (range, 2.7–7.5) months in the high NLR group (≥3.47). The association between NLR and OS was also observed in multivariable Cox regression analysis (hazard ratio, 3.18; 95% confidence interval, 1.15–8.85; p = 0.026). The OS curves differed significantly according to post-RT NLR (p = 0.036). A high NLR before and after RT may be significantly associated with poor OS in patients with ATC who receive RT.

Identification and validation of L Antigen Family Member 3 as an immune-related biomarker associated with the progression of papillary thyroid cancer

BACKGROUND

Papillary thyroid cancer (PTC) is heterogeneous cancer with many different immune cells involved in its pathogenesis. L Antigen Family Member 3 (LAGE3) is an ESO/LAGE gene family member that has not been extensively studied in PTC.

METHODS

Comprehensive bioinformatics analyses of LAGE3 were based on The Cancer Genome Atlas, Gene Expression Omnibus, and Genomics of Drug Sensitivity in Cancer (GDSC) databases. We also performed RNA-sequencing on 78 paired samples from local PTC patients.

RESULTS

We observed that LAGE3 was significantly up-regulated in most solid tumor types, including PTC compared with corresponding normal tissues. The high level of LAGE3 was also significantly associated with advanced malignancy. LAGE3 expression was significantly associated with cancer-related pathways, biochemical metabolism, and immune-related terms. Further, tumor microenvironment analysis indicated LAGE3 was positively correlated with different immune cells infiltrating levels and the activity of different steps of the cancer-immunity cycle. Analyses based on the GDSC database revealed that low levels of LAGE3 might be resistant to WZ3105, I-BET-762, and PHA-793887. In addition, the experimental results validated that knocking down LAGE3 could affect proliferation, migration, and invasion in the PTC cell lines.

CONCLUSION

This study discloses that LAGE3 plays an oncogenic and cancer-immunological role, also providing novel PTC biological and clinical implications.

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.

Lymphocyte-to-monocyte ratio prior to radioiodine ablation in low- and intermediate-risk, papillary thyroid cancer

PURPOSE

We aimed to investigate inflammation indices based on preablation hematological parameter of the lymphocyte-to-monocyte ratio (LMR) to predict the clinical outcome in papillary thyroid cancer (PTC) patients with low- and intermediate-risk stratification.

METHODS

This retrospective study analyzed 772 patients with low- and intermediate-risk PTC who underwent total thyroidectomy followed by radioiodine therapy between July 2005 and July 2009 with a median of 10 years. Kaplan-Meier statistics were used to test differences in recurrence-free survival (RFS) between groups based on the optimal cutoff point of biomarkers identified using receiver operating characteristic curves.

RESULTS

With an optimal cutoff point of 7.05, 215 patients (29.8%) were classified as having low LMR and 557 patients (71.2%) were classified as having high LMR. High LMR was significantly associated with a prolonged RFS (hazard ratio [HR]: 2.048, 95% confidence interval [CI]: 1.062-4.359, p = 0.001). Multivariate analysis showed that low LMR (HR = 2.035, 95% CI: 1.011-4.095, p = 0.012), tumor size over 2 cm (HR = 2.762, 95% CI: 1.303-5.852, p = 0.008), and high preablative simulated thyroglobulin level over 10 ng/ml (HR = 7.826, 95% CI: 2.353-26.033, p < 0.001) were independent prognostic markers for worse RFS in the enrolled PTC patients.

CONCLUSIONS

LMR at the time of radioiodine therapy has comparable predictor for the clinical outcome with both tumor size and preablative simulated thyroglobulin level in low- to intermediate-risk PTC patients.

PD-1, CTLA4, PD-L1 and PD-L2 DNA methylation in papillary thyroid carcinoma

Aim: We investigated DNA methylation patterns of immune checkpoint genes PD-1, PD-L1, PD-L2, CTLA4 and an adjacent long noncoding RNA in papillary thyroid carcinoma (PTC). Materials & methods: DNA methylation and mRNA expression were examined in PTCs. DNA methylation was correlated with mRNA expression, BRAF and RAS mutational status, and immune cell infiltration. Results: Inverse correlations between DNA methylation and mRNA expression were observed. Immune checkpoint expression correlated positively, and DNA methylation negatively, with immune cell infiltration. Higher DNA methylation levels accompanied by lower immune checkpoint expression were observed in RAS-mutated tumors. Conclusion: We suggest epigenetic regulation of immune checkpoints in PTC. Methylation was associated with BRAF and RAS mutation status. DNA methylation might be a promising biomarker candidate in the context of immunotherapies in PTC.

Updates on the Management of Thyroid Cancer

The diagnostic modalities, stratification tools, and treatment options for patients with thyroid cancer have rapidly evolved since the development of the American Thyroid Association (ATA) guidelines in 2015. This review compiles newer concepts in diagnosis, stratification tools and treatment options for patients with differentiated thyroid cancer (DTC), medullary thyroid carcinoma (MTC) and anaplastic thyroid cancer (ATC). Newer developments apply precision medicine in thyroid cancer patients to avoid over-treatment in low risk disease and under-treatment in high risk disease. Among novel patient-tailored therapies are selective RET inhibitors that have shown efficacy in the treatment of MTC with limited systemic toxicity compared with non-specific tyrosine kinase inhibitors. The combination of BRAF and MEK inhibitors have revolutionized management of BRAF V600E mutant ATC. Several immunotherapeutic agents are being actively investigated in the treatment of all forms of thyroid cancer. In this review, we describe the recent advances in the diagnosis and management of DTC, MTC, and ATC, with an emphasis on novel treatment modalities.

Diagnostic and prognostic value of preoperative systemic inflammatory markers in anaplastic thyroid cancer

BACKGROUND

Easily accessible, generalized, and inexpensive methods are expected to differentiate anaplastic thyroid carcinoma (ATC) from advanced differentiated thyroid cancer (aDTC). We aimed to explore potential diagnostic and prognostic value of systematic inflammatory markers (SIMs) in ATC and aDTC.

METHODS

About 22 ATC, 101 aDTC, and 100 matched early DTC patients were analyzed retrospectively. SIMs included the comprehensive index, neutrophil-monocyte-platelet-to-lymphocyte ratio (NMPLR) and the previously reported ones. Receiver operating characteristic, Kaplan-Meier, and COX regression analyses were mainly conducted.

RESULTS

NMPLR exhibited the highest area under the curve value 0.806 (P < .0001) to diagnose ATC from aDTC. NMPLR was identified as an independent risk factor for overall survival (OS) (hazard ratio [HR]: 47.821, 95% confidence interval [CI], 2.863-798.765, P = .007) in ATC, as well as for OS (HR: 7.360, 95% CI, 1.620-33.430, P = .010) and recurrence-free survival (HR: 4.172, 95% CI, 1.139-15.286, P = .031) in aDTC. Taken both refractory types (ATC and aDTC) together, NMPLR could independently predict OS (HR: 6.470; 95% CI, 2.134-19.616; P = .001).

CONCLUSION

NMPLR is a generalized index. It showed excellent potential in differential diagnosis and survival prediction in refractory thyroid cancer. However, it needs to be validated in larger cohort and clinical practice.

Immune gene signature delineates a subclass of thyroid cancer with unfavorable clinical outcomes

Thyroid cancer (THCA) is a heterogeneous disease with multiple clinical outcomes Immune cells regulate its progression. Three immunomolecular subtypes (C1, C2, C3) were identified in gene expression data sets from TCGA and GEO databases. Among them, subtype C3 had highest frequency of BRAF mutations, lowest frequency of RAS mutations, highest mutation load and shorter progression-free survival. Functional enrichment analysis for the genes revealed that C1 was up-regulated in the ERK cascade pathway, C2 was up-regulated in cell migration and proliferation pathways, while C3 was enriched in body fluid, protein regulation and response to steroid hormones functions. Notably, the three molecular subtypes exhibit differences in immune microenvironments as shown by timer database and analysis of immune expression signatures. The abundance of B_cell, CD4_Tcell, Neutrophil, Macrophage and Dendritic cells in C2 subtype were lower than in C1 and C3 subtypes Leukocyte fraction, proliferation macrophage regulation, lymphocyte infiltration, IFN gamma response and TGF beta response scores were significantly higher in C3 compared with C1 and C2 subtypes. Unlike C3 subtype, it was observed that C1 and C2 subtypes were significantly negatively correlated with most immune checkpoint genes in two different cohorts. The characteristic genes were differentially expressed between cancer cells, adjacent tissues, and metastatic tissues in different cohorts. In summary, THCA can be subclassified into three molecular subtypes with distinct histological types, genetic and transcriptional phenotypes, all of which have potential clinical implications.

A Case Report of Sequential Use of a Yeast-CEA Therapeutic Cancer Vaccine and Anti-PD-L1 Inhibitor in Metastatic Medullary Thyroid Cancer

Medullary thyroid cancer (MTC) accounts for ~4% of all thyroid malignancies. MTC derives from the neural crest and secretes calcitonin (CTN) and carcinoembryonic antigen (CEA). Unlike differentiated thyroid cancer, MTC does not uptake iodine and I-131 RAI (radioactive iodine) treatment is ineffective. Patients with metastatic disease are candidates for FDA-approved agents with either vandetanib or cabozantinib; however, adverse effects limit their use. There are ongoing trials exploring the role of less toxic immunotherapies in patients with MTC. We present a 61-year-old male with the diagnosis of MTC and persistent local recurrence despite multiple surgeries. He was started on sunitinib, but ultimately its use was limited by toxicity. He then presented to the National Cancer Institute (NCI) and was enrolled on a clinical trial with heat-killed yeast-CEA vaccine (NCT01856920) and his calcitonin doubling time improved in 3 months. He then came off vaccine for elective surgery. After surgery, his calcitonin was rising and he enrolled on a phase I trial of avelumab, a programmed death-ligand 1 (PD-L1) inhibitor (NCT01772004). Thereafter, his calcitonin decreased > 40% on 5 consecutive evaluations. His tumor was subsequently found to express PD-L1. CEA-specific T cells were increased following vaccination, and a number of potential immune-enhancing changes were noted in the peripheral immunome over the course of sequential immunotherapy treatment. Although calcitonin declines do not always directly correlate with clinical responses, this response is noteworthy and highlights the potential for immunotherapy or sequential immunotherapy in metastatic or unresectable MTC.

Low Lymphocyte-to-Monocyte Ratios Are Associated with Poor Overall Survival in Anaplastic Thyroid Carcinoma Patients

Background: The lymphocyte-to-monocyte ratio (LMR), which reflects the tumor-infiltrating immune cell status and host immunity, has been reported as a prognostic marker in various cancers. The aim of the present study was to evaluate the role of the LMR as a prognostic marker in predicting the survival of patients with anaplastic thyroid carcinoma (ATC). Methods: This study retrospectively included 35 ATC patients with available complete blood cell count data. The primary outcome was the overall survival (OS) of patients with ATC. Results: There were no significant differences between the LMR of the baseline and that of the follow-up complete blood cell count data (p = 0.53). The patients were divided into two groups based on their baseline LMR: a low LMR group (<4; n = 23, 66%) and a high LMR group (≥4; n = 12, 34%). The proportion of cervical lymph node metastasis in the low LMR group was significantly higher than that in the high LMR group (p = 0.021). The OS curves were significantly different based on the LMR values, and the median OS of the low and high LMR groups were 3.0 and 9.5 months, respectively (p = 0.004). In multivariate analysis, a low LMR was also an independent risk factor for all-cause mortality in patients with ATC (hazard ratio = 2.55 [confidence interval 1.08-6.00], p = 0.032) after adjusting for sex, tumor size, and distant metastasis. Conclusions: A low LMR is associated with poor survival in patients with ATC. The LMR could be a simple and stable prognostic biomarker reflecting host immunity in patients with ATC. Further studies are needed to confirm the prognostic role of the LMR in ATC.

Senescent thyrocytes and thyroid tumor cells induce M2-like macrophage polarization of human monocytes via a PGE2-dependent mechanism

BACKGROUND

Thyroid carcinoma includes several variants characterized by different biological and clinical features: from indolent microcarcinoma to undifferentiated and aggressive anaplastic carcinoma. Inflammation plays a critical role in thyroid tumors. Conditions predisposing to cancer, as well as oncogene activity, contribute to the construction of an inflammatory microenvironment that facilitates thyroid tumor progression. Moreover, oncogene-induced senescence, a mechanism tightly connected with inflammation, and able to restrain or promote cancer progression, is involved in thyroid cancer. The interactions between thyroid tumor cells and the microenvironment are not completely clarified.

METHODS

We characterize in vitro the interplay between macrophages and senescent thyrocytes and tumor-derived cell lines, modeling early and late thyroid tumor stages, respectively. Purified peripheral blood-derived human monocytes were exposed to thyroid cell-derived conditioned medium (CM) and assessed for phenotype by flow cytometry. The factors secreted by thyroid cells and macrophages were identified by gene expression analysis and ELISA. The protumoral effect of macrophages was assessed by wound healing assay on K1 thyroid tumor cells. The expression of PTGS2 and M2 markers in thyroid tumors was investigated in publicly available datasets.

RESULTS

Human monocytes exposed to CM from senescent thyrocytes and thyroid tumor cell lines undergo M2-like polarization, showing high CD206 and low MHC II markers, and upregulation of CCL17 secretion. The obtained M2-like macrophages displayed tumor-promoting activity. Among genes overexpressed in polarizing cells, we identified the prostaglandin-endoperoxide synthase enzyme (PTGS2/COX-2), which is involved in the production of prostaglandin E2 (PGE2). By using COX-2 inhibitors we demonstrated that the M2-like polarization ability of thyroid cells is related to the production of PGE2. Co-expression of PTGS2 and M2 markers is observed a significant fraction of human thyroid tumors.

CONCLUSIONS

Our results demonstrate that both senescent thyrocytes and thyroid tumor cell lines trigger M2-like macrophage polarization that is related to PGE2 secretion. This suggests that the interaction with the microenvironment occurs at both early and late thyroid tumor stages, and favors tumor progression. The co-expression of PTGS2 gene and M2 markers in human thyroid carcinoma highlights the possibility to counteract tumor growth through COX-2 inhibition.

Novel Drug Treatments of Progressive Radioiodine-Refractory Differentiated Thyroid Cancer

Systemic therapy options have emerged for treatment of progressive, radioiodine-refractory differentiated thyroid carcinoma. Approved therapies that target tumor angiogenesis, lenvatinib and sorafenib, improve progression-free survival and, in an older subset, lenvatinib can prolong overall survival. Treatments based on targeting specific somatic genetic alterations are also available, which potentially also may prolong progression-free survival but are not yet approved for use by the Food and Drug Administration for this specific disease. More novel approaches that may benefit select patients include resensitization therapies that allow further radioiodine utilization and new immunotherapy concepts.

Diagnosis and Management of Anaplastic Thyroid Cancer

Anaplastic thyroid cancer (ATC) is a devastating and usually incurable diagnosis. Clinical and pathologic diagnosis is best assessed at a tertiary center with concentrated ATC expertise. Expeditious multidisciplinary management is recommended for optimal patient outcomes. Based on multiinstitutional and population-based studies, multimodal therapy that includes chemoradiotherapy with surgery (when feasible) is the preferred initial treatment because it is associated with incrementally improved overall survival. In ATC that carries a BRAF V600E somatic mutation, combination therapy with BRAF and MEK inhibitors has shown promise but needs further study. Immunotherapeutic agents in neoadjuvant and metastatic settings are being investigated.

Time to Separate Persistent From Recurrent Differentiated Thyroid Cancer: Different Conditions With Different Outcomes

CONTEXT

Differentiated thyroid cancer (DTC) has an excellent prognosis, but up to 20% of patients with DTC have disease events after initial treatment, indistinctly defined as persistent/recurrent disease.

OBJECTIVE

To evaluate the prevalence and outcome of "recurrent" disease (relapse after being 12 months disease-free) compared with "persistent" disease (present ab initio since diagnosis).

DESIGN

Retrospective analysis of persistent/recurrent disease in patients with DTC (1990 to 2016) with 6.5 years of mean follow-up.

SETTING

Tertiary referral center for thyroid cancer.

PATIENTS

In total, 4292 patients all underwent surgery ± 131I treatment of DTC.

MAIN OUTCOME MEASURES

DTC cure of disease persistence or recurrence.

RESULTS

A total of 639 of 4292 (14.9%) patients had disease events after initial treatment, most (498/639, 78%) with persistent disease and 141 (22%) with recurrent disease. Relative to patients with recurrent disease, patients with persistent disease were significantly older (mean age 46.9 vs 45.7 years) and with a lower female to male ratio (1.9/1 vs 4.8/1). Moreover, in this group, structured disease was more frequent (65.7% vs 41.1%), and more important, distant metastases were significantly more frequent (38.4% vs 17.0%). At multivariate analysis, male sex (OR = 1.7), age (OR = 1.02), follicular histotype (OR = 1.5), T status (T3; OR = 3), and N status (N1b; OR = 7.7) were independently associated with persistent disease. Only the N status was associated with recurrent disease (N1b; OR = 2.5).

CONCLUSIONS

In patients with DTC not cured after initial treatment, persistent disease is more common and has a worse outcome than recurrent disease. Postoperative status evaluated during first-year follow-up may have important clinical implications for planning tailored treatment strategies and long-term follow-up procedures.

Anti-PD-1/PD-L1 therapy augments lenvatinib's efficacy by favorably altering the immune microenvironment of murine anaplastic thyroid cancer

Patients with anaplastic thyroid cancer (ATC) have an extremely poor prognosis despite multimodal therapy with surgery and chemoradiation. Lenvatinib, a multi-targeted tyrosine kinase inhibitor, as well as checkpoint inhibitors targeting the programmed cell death pathway, have proven effective in some patients with advanced thyroid cancer. Combination of these therapies is a potential means to boost effectiveness and minimize treatment resistance in ATC. We utilized our novel immunocompetent murine model of orthotopic ATC to demonstrate that lenvatinib led to significant tumor shrinkage and increased survival, while combination therapy led to dramatic improvements in both. Lenvatinib monotherapy increased tumor-infiltrating macrophages, CD8⁺ T-cells, regulatory T-cells, and most notably, polymorphonuclear myeloid derived suppressor cells (PMN-MDSCs). While both combination therapies led to further increases in CD8⁺ T-cells, only the lenvatinib and anti-PD-1 combination decreased PMN-MDSCs. PMN-MDSC expansion was also seen in the blood of mice and one patient receiving lenvatinib therapy for ATC. RNA-Seq of the ATC cell line used in our mouse model demonstrated that lenvatinib has multifaceted effects on angiogenesis, response to hypoxia, the epithelial-to-mesenchymal transition, and on multiple pathways implicated in inflammation and host immunity. Combination of lenvatinib with anti-Gr-1 antibody ameliorated lenvatinib's expansion of MDSCs and significantly improved lenvatinib's anti-tumor effect. These data suggest that MDSCs play a negative role in ATC's response to lenvatinib and support future study of their role as a potential biomarker and treatment target.

Immune Gene Signature Delineates a Subclass of Papillary Thyroid Cancer with Unfavorable Clinical Outcomes

Papillary thyroid carcinoma (PTC) represents a heterogeneous disease with diverse clinical outcomes highlighting a need to identify robust biomarkers with clinical relevance. We applied non-negative matrix factorization-based deconvolution to publicly available gene expression profiles of thyroid cancers in the Cancer Genome Atlas (TCGA) consortium. Among three metagene signatures identified, two signatures were enriched in canonical BRAF-like and RAS-like thyroid cancers with up-regulation of genes involved in oxidative phosphorylation and cell adhesions, respectively. The third metagene signature representing up-regulation of immune-related genes further segregated BRAF-like and RAS-like PTCs into their respective subgroups of immunoreactive (IR) and immunodeficient (ID), respectively. BRAF-IR PTCs showed enrichment of tumor infiltrating immune cells, tall cell variant PTC, and shorter recurrence-free survival compared to BRAF-ID PTCs. RAS-IR and RAS-ID PTC subtypes included majority of normal thyroid tissues and follicular variant PTC, respectively. Immunopathological features of PTC subtypes such as immune cell fraction, repertoire of T cell receptors, cytolytic activity, and expression level of immune checkpoints such as and PD-L1 and CTLA-4 were consistently observed in two different cohorts. Taken together, an immune-related metagene signature can classify PTCs into four molecular subtypes, featuring the distinct histologic type, genetic and transcriptional alterations, and potential clinical significance.

Combinations of BRAF inhibitor and anti-PD-1/PD-L1 antibody improve survival and tumour immunity in an immunocompetent model of orthotopic murine anaplastic thyroid cancer

BACKGROUND

Patients with anaplastic thyroid cancer (ATC) have an extremely poor prognosis despite aggressive multimodal therapy. ATC has a high prevalence of BRAFV600E mutations and is associated with an immunosuppressive microenvironment; we previously demonstrated that the combination of BRAF inhibitor and checkpoint inhibitor immunotherapy synergistically reduce tumour volume in an immunocompetent mouse model of orthotopic ATC.

METHODS

We again utilised our mouse model of ATC to assess the combination of BRAFV600E inhibitor PLX4720 and anti-PD-L1 or anti-PD-1 antibody on survival, and performed immune cell profiling of lymphoid and myeloid-lineage cells during maximal treatment response and tumour regrowth.

RESULTS

Combination therapy dramatically improved mouse survival. Maximal tumour reduction was associated with increases in the number and cytotoxicity of CD8+ T cells and NK cells, as well as increases in mostly M1-polarised tumour-associated macrophages (TAM) and decreases in myeloid-derived suppressor-like cells. Regrowth of tumour occurred after 2-3 weeks of ongoing combination therapy, and was most significantly associated with decreased TAMs and a dramatic increase in M2-polarisation.

CONCLUSIONS

Combination of PLX4720 and anti-PD-L1/PD-1 antibody dramatically reduced tumour volume, prolonged survival and improved the anti-tumour immune profile in murine ATC. Tumour growth inevitably recurred and demonstrated re-emergence of an immunosuppressive tumour microenvironment.

Therapeutic advances in anaplastic thyroid cancer: a current perspective

Thyroid cancer incidence is increasing at an alarming rate, almost tripling every decade. In 2017, it was the fifth most common cancer in women. Although the majority of thyroid tumors are curable, about 2-3% of thyroid cancers are refractory to standard treatments. These undifferentiated, highly aggressive and mostly chemo-resistant tumors are phenotypically-termed anaplastic thyroid cancer (ATC). ATCs are resistant to standard therapies and are extremely difficult to manage. In this review, we provide the information related to current and recently emerged first-line systemic therapy (Dabrafenib and Trametinib) along with promising therapeutics which are in clinical trials and may be incorporated into clinical practice in the future. Different categories of promising therapeutics such as Aurora kinase inhibitors, multi-kinase inhibitors, epigenetic modulators, gene therapy using oncolytic viruses, apoptosis-inducing agents, and immunotherapy are reviewed. Combination treatment options that showed synergistic and antagonistic effects are also discussed. We highlight ongoing clinical trials in ATC and discuss how personalized medicine is crucial to design the second line of treatment. Besides using conventional combination therapy, embracing a personalized approach based on advanced genomics and proteomics assessment will be crucial to developing a tailored treatment plan to improve the chances of clinical success.

Navigating Systemic Therapy in Advanced Thyroid Carcinoma: From Standard of Care to Personalized Therapy and Beyond

Thyroid cancer, with the exception of anaplastic thyroid cancer, typically has very favorable outcomes with the standard therapy. However, those that persist, recur, or metastasize are associated with a worse prognosis. Targeted therapy with kinase inhibitors has shown promise in advanced cases of thyroid cancer, and currently five drug regimens are approved for use in clinical practice in the treatment of differentiated, medullary, and anaplastic thyroid cancer, with more options in the pipeline. However, one of the greatest dilemmas is when and how to initiate one of these drugs, and this is discussed herein.

Immune landscape of papillary thyroid cancer and immunotherapeutic implications

Although papillary thyroid cancer (PTC) is curable with excellent survival rate, patients with dedifferentiated PTC suffer the recurrence or death. As cancer immune escape plays a critical role in cancer progression, we aimed to investigate the relationship between differentiation and immune landscape of PTC and its implications for immunotherapy. Using The Cancer Genome Atlas data, we estimated the immune cell enrichment scores and overall immune infiltration, ImmuneScore, to characterize the immune landscape of PTC. Thyroid differentiation score (TDS) was calculated from 16 thyroid function genes. We demonstrated that ImmuneScore had a significant negative correlation with TDS, and BRAF^V600E+ tumors showed significantly low TDS and high ImmuneScore. Enrichment scores of myeloid cells and B-cells were negatively correlated with TDS, while those of plasma cells were positively correlated with TDS. In addition, the association between TDS, ImmuneScore and immunosuppressive markers (CTLA-4, PD-L1, HLA-G) were evaluated according to BRAF^V600E status. All immunosuppressive markers expression had a significant negative correlation with TDS, and they were significantly higher in BRAF^V600E+ status. Subgroups were divided by median values of TDS and ImmuneScore, and immunosuppressive markers of these subgroups were compared. The immunosuppressive markers expression was the highest in high ImmuneScore and low TDS subgroup. Furthermore, ImmuneScore had a significant association with recurrence-free survival, irrespective of clinicopathologic factors including BRAF^V600E status. These findings based on gene expression data illuminate the immune landscape of PTC and its association with TDS, immunosuppressive markers and recurrence. Our results would be extended to investigate immunotherapeutic approaches in PTC.

Novel therapies against aggressive differentiated thyroid carcinomas

The incidence of thyroid cancer (TC) is increasing. Although the majority of these cancers have a good prognosis, 10% of these will develop local recurrence and/or distant metastases. Conventional cytotoxic chemotherapy has been largely replaced by molecular-target therapies, but it can still have a role. Two tyrosine kinase inhibitors have been approved for the treatment of advanced differentiated TC. They significantly improve progression-free survival, but at the cost of frequent and potentially serious adverse effects. At the moment, there are multiple clinical trials with other tyrosine kinase inhibitors and other drugs. We present a review of the current standard of care and what is up to come in the treatment of advanced TC.

Recent advances in managing differentiated thyroid cancer

The main clinical challenge in the management of thyroid cancer is to avoid over-treatment and over-diagnosis in patients with lower-risk disease while promptly identifying those patients with more advanced or high-risk disease requiring aggressive treatment. In recent years, novel clinical and molecular data have emerged, allowing the development of new staging systems, predictive and prognostic tools, and treatment approaches. There has been a notable shift toward more conservative management of low- and intermediate-risk patients, characterized by less extensive surgery, more selective use of radioisotopes (for both diagnostic and therapeutic purposes), and less intensive follow-up. Furthermore, the histologic classification; tumor, node, and metastasis (TNM) staging; and American Thyroid Association risk stratification systems have been refined, and this has increased the number of patients in the low- and intermediate-risk categories. There is now a need for new, prospective data to clarify how these changing practices will impact long-term outcomes of patients with thyroid cancer, and new follow-up strategies and biomarkers are still under investigation. On the other hand, patients with more advanced or high-risk disease have a broader portfolio of options in terms of treatments and therapeutic agents, including multitarget tyrosine kinase inhibitors, more selective BRAF or MEK inhibitors, combination therapies, and immunotherapy.

Recent advances in the biology and therapy of medullary thyroid carcinoma

Medullary thyroid cancer (MTC) is a relatively uncommon yet prognostically significant thyroid cancer. Several recent advances in the biology and current or potential treatment of MTC are notable. These include a new understanding of the developmental biology of the thyroid C cell, which heretofore was thought to develop from the neural crest. RET, encoded by the most common driver gene in MTC, has been shown to be a dual function kinase, thus expanding its potential substrate repertoire. Promising new therapeutic developments are occurring; many have recently progressed to clinical development. There are new insights into RET inhibitor therapy for MTC. New strategies are being developed to inhibit the RAS proteins, which are potential therapeutic targets in MTC. Potential emerging immunotherapies for MTC are discussed. However, gaps in our knowledge of the basic biology of the C cell, its transformation to MTC, and the mechanisms of resistance to therapy impede progress; further research in these areas would have a substantial impact on the field.

Current and future immunotherapies for thyroid cancer

INTRODUCTION

Cancer immunotherapies were approved in recent years, including immune checkpoint inhibitors. Experience with ipilimumab (CTLA-4 antagonist), nivolumab and pembrolizumab (PD-1 antagonists), and atezolizumab (PD-L1 antagonist) has shown that the impact on overall survival in cancer patients is paramount. Immune checkpoint inhibitors target the immune system and they can be applied across multiple cancers; the response rate is ranging from 20 to 40%. Many studies have shown that thyroid cancer (TC) cells produce cytokines and chemokines, inducing several tumor-promoting effects. Targeting and/or lowering cytokines and chemokines concentrations within the tumor microenvironment would produce a therapeutic benefit. In TC, increased Treg and PD-1⁺ T cell frequencies are indicative of aggressive disease and PD-L1 expression correlates with a greater risk of recurrence. Area covered: After performing a literature search, a few pioneering studies have evaluated immunotherapy in thyroid cancer. More recently a case has been described involving anaplastic thyroid cancer treated with vemurafenib and nivolumab, with substantial regression and complete radiographic and clinical remission. Expert commentary: The use of immune checkpoint inhibitors in aggressive TC has not yet been extensively investigated and further studies in a large number of TC patients are urgently needed.

Pathological processes and therapeutic advances in radioiodide refractory thyroid cancer

While in most patients with non-medullary thyroid cancer (TC), disease remission is achieved by thyroidectomy and ablation of tumor remnants by radioactive iodide (RAI), a substantial subgroup of patients with metastatic disease present tumor lesions that have acquired RAI resistance as a result of dedifferentiation. Although oncogenic mutations in BRAF, TERT promoter and TP53 are associated with an increased propensity for induction of dedifferentiation, the role of genetic and epigenetic aberrations and their effects on important intracellular signaling pathways is not yet fully elucidated. Also immune, metabolic, stemness and microRNA pathways have emerged as important determinants of TC dedifferentiation and RAI resistance. These signaling pathways have major clinical implications since their targeting could inhibit TC progression and could enable redifferentiation to restore RAI sensitivity. In this review, we discuss the current insights into the pathological processes conferring dedifferentiation and RAI resistance in TC and elaborate on novel advances in diagnostics and therapy to improve the clinical outcome of RAI-refractory TC patients.