A systematic review of multimodal clinical biomarkers in the management of thyroid eye disease

Identification of key extracellular proteins as the potential biomarkers in thyroid eye disease

BACKGROUND

Thyroid eye disease (TED) is one of the most common autoimmune orbital diseases in adults. The early diagnosis and effective treatment of TED is a worldwide problem. Extracellular proteins may act as indicators in bodily fluids. Our research sought to identify the roles of extracellular proteins and possible biomarkers in TED using a bioinformatics study.

METHODS

Data from Gene Expression Omnibus (GEO) were acquired to create the TED expression profiles. The annotation database screened extracellular proteins with differentially expressed genes (EP-DEGs). To investigate both the function and the route of EP-DEGs, GO and KEGG were utilized. Hub genes and protein-protein interaction (PPI) networks among EP-DEGs were discovered. Key EP-DEGs' diagnostic potency was assessed using the receiver operating characteristic (ROC) curve.

RESULTS

102 EP-DEGs underwent screening. The extracellular matrix, which contains collagen, the receptor-ligand activity, the interaction between cytokines and their receptors, and the complement and coagulation cascades route, were all enhanced in EP-DEGs. The EP-DEG PPI network contained 233 edges and 78 nodes. We discovered 21 extracellular proteins that interacted with EGFR in addition to 3 major extracellular proteins, EGFR, CD44, and CXCL8, all of which had significant values of AUC (> 0.7).

CONCLUSIONS

In conclusion, EGFR, CD44, and CXCL8 may be the potential biomarker in the TED. this research gives us a theoretical foundation for understanding how TED pathogenesis occurs.

Evaluation of the clinical management of Graves' Orbitopathy according to severity: a real-life Analysis

PURPOSE

Due to the clinical and prognostic implications of Graves' Orbitopathy (GO), clinical care needs to be tailored to current recommendations, but real-life information is scarce. We aim to describe GO management in a real-life setting for health care improvement.

METHODS

This is a retrospective cohort study evaluating the clinical performance of clinicians attending patients diagnosed with GO. All cases with GO from 2018 to 2021 were included in the analysis, with no exclusion criteria. We performed an evaluation of the healthcare provided to these patients, with clinical performance evaluated from diagnostic and therapeutic viewpoints. A backwards stepwise multivariate binomial logistic regression analysis was run to assess the variables associated with severity.

RESULTS

This was a cohort of 151 cases, predominantly of women in the fifth decade of life, most of whom had hyperthyroidism. There were 50 (33.1%) cases with moderate-severe GO, but none of them with sight-threatening disease. Total annualized visits were more frequent to endocrinologists than ophthalmologists, except for moderate-severe cases. Active smoking (57 cases; 37.7%), unstable hyperthyroidism (59 cases; 39.1%), and elevated maximum TSI levels (136; 90.1%) conditioned clinical care. Altogether, the performance of an imaging technique, the use of systemic corticosteroid therapy and eyelid surgery were significantly different in those with more severe GO.

CONCLUSION

Clinical care provided to patients with GO is variable and influenced by several variables. Both endocrinologists and ophthalmologists must coordinate to ensure a unified patient-tailored protocol that covers all these patients' needs.

Role of biomarkers in South Indian Thyroid Eye Disease study (SITED)

PURPOSE

Thyroid eye disease (TED) is a complex autoimmune disease. Early detection with routine disease monitoring using biomarker assessment would help in mitigating TED-associated vision loss. Hence, we performed a non-invasive tear fluid (TF) based screening in patients with TED as part of the South Indian Thyroid Eye Disease Study (SITED).

MATERIALS AND METHODS

We used TF from healthy controls (HC;13 eyes;13 subjects), patients with thyroid dysfunction but without TED (No TED;11 eyes;11 subjects) and patients with TED (18 eyes;18 subjects). TED subjects were further sub-divided into those with and without an active form of the disease. Patients with dysthyroid optic neuropathy (DON) were analyzed separately. The diagnosis of TED was based on Gorman and Bartley's criteria. Activity was defined as scoring more than 4 in the Vision, Inflammation, Strabismus and Appearance (VISA). Schirmer's strip was used to collect TF and the levels of IL-2, IL-4, IL-5, IL-6, IL-7, IL-9, IL-10, IL-13, IL-17A, IL-17F, IL-22, IFNγ, TNFα, PDGF-AA and PDGF-BB were determined by multiplex ELISA using flow cytometry.

RESULTS

Significantly (p < 0.05) higher levels of IL-6 and IL-10 were observed in TED patients compared to HC and No TED subjects. TF levels of IL-6 and IL-10 were significantly higher in active TED patients compared to No TED subjects. Interestingly, TF levels of PDGF-AA were observed to be negatively associated with IL-4 and IL-13.

CONCLUSION

Elevated TF levels of IL-6 and IL-10 can be explored for their role as a non-invasive risk stratification biomarker or as targets to modulate management of TED.

Tear-fluid-derived biomarkers of ocular complications in diabetes: a systematic review and meta-analysis

BACKGROUND

Early identification and management of sight-threatening ocular complications of diabetes using imaging or molecular biomarkers could help prevent vision loss. However, access to specialized infrastructure and expertise is limited, especially in remote areas of the world. Tear-fluid may offer an easier, non-invasive, and localized screenshot of ocular disease. To the best of our knowledge, there is no systematic review and meta-analysis on tear-fluid-based biomarkers for ocular complications in diabetes.

METHODS

Articles were extracted from PubMed, Embase, Medline, and Web of Science using the MeSH and Emtree terms. The keywords include (diabetes), (diabetic retinopathy), (diabetes mellitus, type 1), (diabetes mellitus, type 2), (insulin-dependent diabetes), (insulin resistant diabetes), (tears), (lacrimal fluid), (biological marker), and (biomarker, marker). Concentrations of tear-fluid biomarkers in individuals with diabetes, diabetic ocular complications, and healthy controls were extracted and standardized mean differences (SMDs) and 95% CIs were calculated. Heterogeneity was assessed using subgroup and leave-one-out sensitivity analyses. Publication and risk of bias were performed using the Egger's test and Cochrane guidelines. The quality of evidence was evaluated using the Newcastle-Ottawa scale.

RESULTS

Nine hundred eleven papers were identified, 19 of which met the study criteria and were included in the meta-analysis. Participants (n = 1413) belonged to three groups: healthy controls (Controls), diabetes without any complications (Diabetes), and diabetes with ocular complications (Complications). Actual concentrations were reported for TNF-α, VEGF, IL-1RA, IL-1β, IL-6, IL-8, lactoferrin, lysozyme, and MCP-1 in at least three different studies. Meta-analyses demonstrated that TNF-α concentration was significantly higher in the tear-fluid of Complications group when compared to Controls (SMD = - 1.08, 95% CIs = - 1.78, - 0.38, p = 0.003) or when compared to Diabetes (SMD = - 0.78, 95% CIs = - 1.48, - 0.09, p = 0.03). However, it was not different when Controls were compared to Diabetes (SMD = - 1.00, 95% CIs = - 2.27, 0.28, p = 0.13). VEGF demonstrated a similar trend indicating specificity of tear-fluid TNF-α and VEGF for diabetic ocular complications.

CONCLUSIONS

Across all biomolecules meta-analyzed in this study, TNF-α and VEGF were identified as the most important biomarkers that could potentially offer a non-invasive tear-fluid-based assessment of progression to ocular complications in diabetes, especially in rural and remote areas where diabetes-related expertise and infrastructure are limited.

TRIAL REGISTRATION

PROSPERO (CRD42023441867) https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=441867 .

Thyroid stimulating immunoglobulin concentration is associated with disease activity and predicts response to treatment with intravenous methylprednisolone in patients with Graves' orbitopathy

Background

Thyroid stimulating immunoglobulins (TSI) play a central role in the pathogenesis of Graves' orbitopathy (GO), while soluble interleukin-2 receptor (sIL-2R) is a marker for T-cell activity. We investigated TSI and sIL-2R levels in relation to thyroid function, disease activity and severity and response to treatment with intravenous methylprednisolone (IVMP) in patients with GO.

Methods

TSI (bridge-based TSI binding assay), sIL-2R, TSH and fT4 levels were measured in biobank serum samples from 111 GO patients (37 male, 74 female; mean age 49.2 years old) and 25 healthy controls (5 male, 20 female; mean age 39.8 years old). Clinical characteristics and response to treatment were retrospectively retrieved from patient files.

Results

Higher sIL-2R levels were observed in GO patients compared to controls (p < 0.001). sIL-2R correlated with fT4 (r = 0.26), TSH (r = -0.40) and TSI (r = 0.21). TSI and sIL-2R concentrations were higher in patients with active compared to inactive GO (p < 0.001 and p < 0.05, respectively). Both TSI and sIL-2R correlated with total clinical activity score (CAS; r = 0.33 and r = 0.28, respectively) and with several individual CAS items. Cut-off levels for predicting active GO were 2.62 IU/L for TSI (AUC = 0.71, sensitivity 69%, specificity 69%) and 428 IU/mL for sIL-2R (AUC = 0.64, sensitivity 62%, specificity 62%). In multivariate testing higher TSI (p < 0.01), higher age (p < 0.001) and longer disease duration (p < 0.01) were associated with disease activity. TSI levels were higher in patients with a poor IVMP response (p = 0.048), while sIL-2R levels did not differ between responders and non-responders. TSI cut-off for predicting IVMP response was 19.4 IU/L (AUC = 0.69, sensitivity 50%, specificity 91%). In multivariate analysis TSI was the only independent predictor of response to IVMP (p < 0.05).

Conclusions

High TSI levels are associated with active disease (cut-off 2.62 IU/L) and predict poor response to IVMP treatment (cut-off 19.4 IU/L) in GO. While sIL-2R correlates with disease activity, it is also related to thyroid function, making it less useful as an additional biomarker in GO.

Molecular Biomarkers in Thyroid Eye Disease: A Literature Review

PURPOSE

Thyroid eye disease (TED) is the most common extrathyroidal manifestation of Graves disease. Patients may be severely affected with eyelid retraction, exophthalmos, diplopia, pain, and threatened vision. Autoantibodies against thyroid-stimulating hormone receptor and insulin-like growth factor 1 receptor have shown associations with pathophysiological and clinical traits. Autoantibodies against thyroid-stimulating hormone receptor is in current clinical use as biomarker, but not with unambiguous diagnostic performance. A biomarker with high diagnostic accuracy and/or prognostic capability would be of immense value in diagnosing TED, especially in subclinical cases or when TED precedes the thyroid dysfunction. This article is a literature review on molecular biomarkers of TED.

METHODS

A literature search was performed using PubMed and Embase. Studies on molecular biomarkers in blood, tear fluid, and urine were included in the review.

RESULTS

Forty-six papers were included, of which 30, 14, and 2 studies on biomarkers in blood, tears, and urine, respectively. Fourteen of the papers evaluated the diagnostic performance of various biomarkers, 12 in blood and 2 in tears. Most studies evaluated single biomarkers, but 3 tested a panel of several markers. Except for autoantibodies against thyroid-stimulating hormone receptor, the reported diagnostic performances for the biomarkers were not confirmed in independent cohorts. In 32 studies, no or insufficient performance data were given, but the findings indicated involvement of various biologic mechanisms in TED including inflammation, oxidative stress, fibrosis, lipid metabolism, and ocular surface microflora.

CONCLUSIONS

Currently, serum autoantibodies against thyroid-stimulating hormone receptor is the only molecular biomarker with clinical utility in patients with TED. Several potential biomarkers have been investigated, and particularly panels of multiple biomarkers in tears are promising. To improve patient care, biomarkers in TED should be studied further.

Tears as a Source of Biomarkers in the Diagnosis of Graves' Orbitopathy

Thyroid eye disease (TED) is a poorly understood autoimmune manifestation of thyroid diseases most commonly associated with Graves' disease. Due to a lack of specific biomarkers and uncertain signs and symptoms, Graves' orbitopathy (GO) is challenging to diagnose early and treat effectively. Nowadays, there is great interest in searching for precise molecular biomarkers for early detection, disease monitoring, and clinical management. Researchers are keen to identify novel methods to predict and diagnose diseases and to monitor patient therapeutic response. Tears, due to their direct contact with the eye and the fact that lacrimal glands can also be affected by the disease, could give new insights into the mechanisms taking place in thyroid-associated orbitopathy (TAO) and reveal potential promising biomarkers. Tear fluid offers the possibility of the non-invasive acquisition of a sample with a high protein content, thereby attracting continuously growing interest in the discovery of novel biomarkers. This article provides an up-to-date overview of the various putative tear-fluid biomarkers that have been identified. In this review, we present the potential use of tears as a diagnostic fluid and tool to investigate the mechanism of ocular diseases and discuss the future research directions in this area.

Comprehensive analysis of key genes and pathways for biological and clinical implications in thyroid-associated ophthalmopathy

Background

Thyroid-associated ophthalmopathy (TAO) is a common and organ-specific autoimmune disease. Early diagnosis and novel treatments are essential to improve the prognosis of TAO patients. Therefore, the current work was performed to identify the key genes and pathways for the biological and clinical implications of TAO through comprehensive bioinformatics analysis and a series of clinical validations.

Methods

GSE105149 and GSE185952 were obtained from the Gene Expression Omnibus (GEO) database for analysis. The data were normalized to identify the common differentially expressed genes (DEGs) between the two datasets, and the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to assess key pathways in TAO. Protein–protein interaction (PPI) networks and hub genes among the common DEGs were identified. Furthermore, we collected the general information and blood samples from 50 TAO patients and 20 healthy controls (HCs), and the expression levels of the proteins encoded by hub genes in serum were detected by enzyme-linked immunosorbent assay (ELISA). Then we further assessed the relationship between the ELISA data and the TAO development.

Results

Several common pathways, including neuroactive ligand-receptor interaction, the IL-17 signaling pathway, and the TNF signaling pathway, were identified in both datasets. In parallel, 52 common DEGs were identified. The KEGG analysis showed that these common DEGs are mainly enriched in long-term depression, the VEGF signaling pathway, the IL-17 signaling pathway, the TNF signaling pathway, and cytokine-cytokine receptor interactions. The key hub genes PRKCG, OSM, DPP4, LRRTM1, CXCL6, and CSF3R were screened out through the PPI network. As confirmation, the ELISA results indicated that protein expression levels of PRKCG, OSM, CSF3R, and DPP4 were significantly upregulated in TAO patients compared with HCs. In addition, PRKCG and DPP4 were verified to show value in diagnosing TAO, and CSF3R was found to be a valuable diagnostic marker in distinguishing active TAO from inactive TAO.

Conclusions

Inflammation- and neuromodulation-related pathways might be closely associated with TAO. Based on the clinical verification, OSM, CSF3R, CXCL6, DPP4, and PRKCG may serve as inflammation- or neuromodulation-related biomarkers for TAO, providing novel insights for the diagnosis and treatment of TAO.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08854-5.