Papillary thyroid carcinoma: differential diagnosis and prognostic values of its different variants: review of the literature

TLE4 downregulation identified by WGCNA and machine learning algorithm promotes papillary thyroid carcinoma progression via activating JAK/STAT pathway

Background: Papillary Thyroid Carcinoma (PTC), a common type of thyroid cancer, has a pathogenesis that is not fully understood. This study utilizes a range of public databases, sophisticated bioinformatics tools, and empirical approaches to explore the key genetic components and pathways implicated in PTC, particularly concentrating on the Transducin-Like Enhancer of Split 4 (TLE4) gene. Methods: Public databases such as TCGA and GEO were utilized to conduct differential gene expression analysis in PTC. Hub genes were identified using Weighted Gene Co-expression Network Analysis (WGCNA), and machine learning techniques, including Random Forest, LASSO regression, and SVM-RFE, were employed for biomarker identification. The clinical impact of the TLE4 gene was assessed in terms of diagnostic accuracy, prognostic value, and its functional enrichment analysis in PTC. Additionally, the study focused on understanding the role of TLE4 in the dynamics of immune cell infiltration, gene function enhancement, and behaviors of PTC cells like growth, migration, and invasion. To complement these analyses, in vivo studies were performed using a xenograft mouse model. Results: 244 genes with significant differential expression across various databases were identified. WGCNA indicated a strong link between specific gene modules and PTC. Machine learning analysis brought the TLE4 gene into focus as a key biomarker. Bioinformatics studies verified that TLE4 expression is lower in PTC, linking it to immune cell infiltration and the JAK-STAT signaling pathways. Experimental data revealed that decreased TLE4 expression in PTC cell lines leads to enhanced cell growth, migration, invasion, and activates the JAK/STAT pathway. In contrast, TLE4 overexpression in these cells inhibited tumor growth and metastasis. Conclusions: This study sheds light on TLE4's crucial role in PTC pathogenesis, positioning it as a potential biomarker and target for therapy. The integration of multi-omics data and advanced analytical methods provides a robust framework for understanding PTC at a molecular level, potentially guiding personalized treatment strategies.

Visualizing Dipeptidyl Peptidase-IV with an Advanced Non-π-Conjugated Fluorescent Probe for Early Thyroid Disease Diagnosis

Early detection and effective treatment of thyroid cancer are vital due to the aggressiveness and high mortality rate of the cancer. Nevertheless, the exploration of dipeptidyl peptidase-IV (DPP-IV) as a biomarker for thyroid diseases has not been widely conducted. In this study, we developed a novel non-π-conjugated near-infrared fluorescent probe, MB-DPP4, specifically designed to visualize and detect endogenous DPP-IV. Traditional DPP-IV-specific fluorescent probes rely primarily on the intramolecular charge transfer mechanism. For this reason, these probes are often hampered by high background levels that can inhibit their ability to achieve a fluorescence turn-on effect. MB-DPP4 successfully surmounts several drawbacks of traditional DPP-IV probes, boasting unique features such as exceptional selectivity, ultrahigh sensitivity (0.29 ng/mL), innovative structure, low background, and long-wavelength fluorescence. MB-DPP4 is an "off-on" chemosensor that exhibits strong fluorescence at 715 nm and releases a methylene blue (MB) fluorophore upon interacting with DPP-IV, resulting in a visible color change from colorless to blue. Given these remarkable attributes, MB-DPP4 shows great promise as a versatile tool for advancing research on biological processes and for evaluating the physiological roles of DPP-IV in living systems. Finally, we conducted a comprehensive investigation of DPP-IV expression in human serum, urine, thyroid cells, and mouse thyroid tumor models. Our findings could potentially establish a foundation for the early diagnosis and treatment of thyroid diseases.

Investigation of Parvovirus B19, Cytomegalovirus, Herpes Simplex Virus Types 1 and 2, Human Papillomavirus Types 16 and 18 in Papillary Thyroid Carcinoma

Background & Objective

Viral infections are associated with the pathogenesis and progression of human malignancies. Several studies have suggested the role of viral infections in papillary thyroid carcinoma (PTC). However, the results are still conflicting, and the potential role of viruses in PTC tumorigenesis remains to be elucidated. In the present study, we aimed to investigate the presence of parvovirus B19, cytomegalovirus (CMV), herpes simplex virus types 1 and 2 (HSV-1/HSV-2), and human papillomavirus (HPV) types 16 and 18 in PTC.

Methods

In this cross-sectional study, paraffin-embedded tissue blocks of 40 patients with PTC were used. Tissue blocks were studied for the presence of the virus genome using real-time polymerase chain reaction (PCR).

Results

Of the 40 patients with PTC, there was 1 positive case of HPV (2.5%), while 6 cases were positive for parvovirus B19. HSV and CMV DNAs were not detected in any cases.

Conclusion

Correlations among HSV, CMV, and PTC are unexpected in our patient population. But parvovirus B19 and, to a lesser extent, HPV DNA genomes were detected in PTC using real-time PCR.

Oncocytic Papillary Carcinoma in an Autonomous Thyroid Nodule

Patient: Female, 30-year-old

Final Diagnosis: Papillary thyroid carcinoma

Symptoms: Hyperthyroidism • thyroid mass

Medication: —

Clinical Procedure: Thyroidectomy

Specialty: Surgery

OGT regulated O-GlcNAcylation promotes papillary thyroid cancer malignancy via activating YAP

The incidence of thyroid cancer is growing rapidly during the past decades worldwide. Although most thyroid tumors are curable, some patients diagnosed with distant metastases are associated with poor prognosis. The molecular mechanisms underlying these cases are still largely unknown. Here we found that the upregulated O-Linked N-Acetylglucosamine Transferase (OGT) expression and O-GlcNAcylation (O-GlcNAc) modification in papillary thyroid cancer (PTC) were essential in tumor growth and metastasis. Mass spectrometry analysis showed that YAP was the effector protein modified by OGT. In details, YAP Ser109 O-GlcNAcylation promoted the malignant phenotypes in PTC cells by inducing YAP Ser127 dephosphorylation and activation. Our work clearly showed the critical role of OGT and YAP played in PTC tumors and made it possible for us to seek the clinical potential of manipulating OGT/YAP activity in PTC targeted therapies. These findings also confirmed OGT worked in collaboration with classical Hippo pathway kinases as an upstream regulator of YAP in PTC tumors.

POLE and POLD1 pathogenic variants in the proofreading domain in papillary thyroid cancer

Thyroid cancer is the most frequent endocrine cancer with an increasing incidence rate worldwide and is the second most common malignancy among females in Saudi Arabia. Papillary thyroid cancer (PTC) is the most common subtype. Germline pathogenic variants in the proofreading domain of the POLE and POLD1 genes predispose to several types of cancers. However, the role of pathogenic variants of these two genes in PTC remains unknown. Capture sequencing, Sanger sequencing and immunohistochemistry were performed on 300 PTC cases from the Middle Eastern region. One germline pathogenic variant each of POLE (1/300, 0.33%) and POLD1 (1/300, 0.33%) genes was identified. Low expression of POLD1 was detected in 46.5% (133/286) of cases and was significantly associated with the follicular variant of PTC (P = 0.0006), distant metastasis (P = 0.0033) and stage IV tumours (P = 0.0081). However, no somatic pathogenic variant was detected in POLE gene. Furthermore, low expression of POLE was noted in 61.7% (175/284) of cases with no significant clinicopathological associations. Our study shows that pathogenic variant in the POLE and POLD1 proofreading domain is a cause of PTC and low expression of POLD1 is associated with poor prognostic markers in the Middle Eastern population. Further studies from different geographic populations are needed to determine the frequency and spectrum of proofreading domain pathogenic variants in POLE and POLD1 genes and in PTC from different ethnicities.

Papillary carcinoma thyroid with anastomosing channels: An unusual morphology

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy, accounting for 70%–80% of all thyroid malignancies. It is biologically indolent and has an excellent prognosis. Variations in histopathologic patterns are known to influence prognosis and often result in a diagnostic dilemma. We report an unusual case of a 35-year-old female with papillary carcinoma of a thyroid isthmus showing anastomosing channels on histopathology, a distinctive pattern that has not been described in PTC. Similar to tumor cells, the lining cells of these channels were also positive for thyroid transcription factor 1, thyroglobulin, and cytokeratin-19 and negative for CD34 and CD31. The diagnosis of PTC should rely on nuclear morphology rather than architecture. Pathologists should be aware of different variants because some of these variants show aggressive behavior and poor outcome. The present report highlights the distinctive pattern of PTC, recognition of which is important to avoid any diagnostic pitfall.

A Case Rarity: Papillary Thyroid Carcinoma with Squamous Metaplasia Complicated with Chronic Discharging Ulcers

We report a unique case of differentiated thyroid carcinoma (DTC) with squamous metaplasia complicated with chronic discharging ulcer. A 76-year-old gentleman was referred to us after defaulted treatment 1 year post-total thyroidectomy. He presented to us with long-standing chronic, non-healing, ulcerative and discharging wound at the anterior neck at previous total thyroidectomy scar. The primary tumour was histologically diagnosed as papillary malignant cells with extensive squamous metaplasia. Squamous metaplasia is a rare finding in thyroid carcinoma that carried a poorer prognostic factor.

Rapid detection of papillary thyroid carcinoma by fluorescence imaging using a γ-glutamyltranspeptidase-specific probe: a pilot study

Background

Nodular lesions of the thyroid gland, including papillary thyroid carcinoma (PTC), may be difficult to diagnose by imaging, such as in ultrasonic echo testing, or by needle biopsy. Definitive diagnosis is made by pathological examination but takes several days. A more rapid and simple method to clarify whether thyroid nodular lesions are benign or malignant is needed. Fluorescence imaging with γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) uses γ-glutamyltranspeptidase (GGT), a cell-surface enzyme, to hydrolyze the γ-glutamyl peptide and transfer the γ-glutamyl group. GGT is overexpressed in several cancers, such as breast, lung, and liver cancers. This imaging method is rapid and useful for detecting such cancers. In this study, we tried to develop a rapid fluorescence detection method for clinical samples of thyroid cancer, especially papillary carcinoma.

Methods

Fluorescence imaging with gGlu-HMRG was performed to detect PTC using 23 surgically resected clinical samples. A portable imaging device conveniently captured white-light images and fluorescence images with blue excitation light. Hematoxylin-eosin (HE) staining was used to evaluate which fluorescent regions coincided with cancer, and immunohistochemical examination was used to detect GGT expression.

Results

All 16 PTC samples exhibited fluorescence after topical application of gGlu-HMRG, whereas the normal sections of each sample showed no fluorescence. HE staining revealed that each fluorescent region corresponded to a region with carcinoma. The PTC samples also exhibited GGT expression, as confirmed by immunohistochemistry.

Conclusions

All PTC samples were detected by fluorescence imaging with gGlu-HMRG. Thus, fluorescence imaging with gGlu-HMRG is a rapid, simple, and powerful detection tool for PTC.

miR-329 inhibits papillary thyroid cancer progression via direct targeting WNT1

Dysregulated microRNA-329 (miR-329) serves an important role in the progression of certain types of tumor. However, the exact function and mechanisms of miR-329 in papillary thyroid cancer (PTC) remain unknown. The present study investigated the function and mechanisms of miR-329 in regulating PTC cell progression. The results revealed that the expression of miR-329 was significantly downregulated in PTC tissues and cell lines compared with adjacent normal tissues and a human immortalized follicular cell line. miR-329 mimics notably decreased PTC cell proliferation, colony formation and WNT1 expression in vitro, as well as suppressing PTC tumor growth in vivo. In addition, luciferase assays determined that miR-329 was able to directly bind with the 3'untranslated region of WNT1. Furthermore, short interfering RNA-WNT1-induced downregulation of WNT1, which demonstrated similar effects to miR-329 overexpression. WNT1 overexpression rescued the tumor suppressive effects of miR-329 in PTC cells. The present study provided new insights into the role of miR-329 in PTC progression and suggests the potential application of miR-329 as a therapy for PTC.

Loss of One or Two PATZ1 Alleles Has a Critical Role in the Progression of Thyroid Carcinomas Induced by the RET/PTC1 Oncogene

POZ/BTB and AT-hook-containing zinc finger protein 1 (PATZ1) is an emerging cancer-related gene that is downregulated in different human malignancies, including thyroid cancer, where its levels gradually decrease going from papillary thyroid carcinomas (PTC) to poorly differentiated and undifferentiated highly aggressive anaplastic carcinomas (ATC). The restoration of PATZ1 expression in thyroid cancer cells reverted their malignant phenotype by inducing mesenchymal-to-epithelial transition, thus validating a tumor suppressor role for PATZ1 and suggesting its involvement in thyroid cancer progression. Here, we investigated the consequences of the homozygous and heterozygous loss of PATZ1 in the context of a mouse modeling of PTC, represented by mice carrying the RET/PTC1 oncogene under the thyroid specific control of the thyroglobulin promoter RET/PTC1 (RET/PTC1^TG). The phenotypic analysis of RET/PTC1^TG mice intercrossed with Patz1-knockout mice revealed that deficiency of both Patz1 alleles enhanced thyroid cancer incidence in RET/PTC1^TG mice, but not the heterozygous knockout of the Patz1 gene. However, both RET/PTC1^TG;Patz1^+/− and RET/PTC1^TG;Patz1^−/− mice developed a more aggressive thyroid cancer phenotype—characterized by higher Ki-67 expression, presence of ATCs, and increased incidence of solid variants of PTC—than that shown by RET/PTC1^TG; Patz1^+/+ compound mice. These results confirm that PATZ1 downregulation has a critical role in thyroid carcinogenesis, showing that it cooperates with RET/PTC1 in thyroid cancer progression.

A meta-analysis on the effect of operation modes on the recurrence of papillary thyroid microcarcinoma

Whether total thyroidectomy reduces the recurrence rate in patients with papillary thyroid microcarcinoma (PTMC) is currently controversy. Conclusions of sporadic, inconsistent, and mono-institutional studies need a meta-analysis to evaluate. 525 relevant studies were obtained from initial search on PubMed, 511 studies were excluded by inclusion and exclusion criteria. Eligible data were extracted from each included study. The Odds ratios (ORs) and 95% confidence interval (CI) were used to assess the difference in the recurrence rates between PTMC patients treated with total thyroidectomy and non-total thyroidectomy. OR and 95% CI were calculated using a fixed-effects or a random-effects model. The Q statistic was used to evaluate homogeneity and Beggs test was used to assess publication bias. 14 studies meeting the inclusion criteria were included in this meta-analysis. The over all recurrence rates of pooled patients with total thyroidectomy and non-total thyroidectomy were 2.83% and 2.84% respectively. Primary random-effects model analysis showed, no significant difference of recurrence rates existed between two operation modes (OR = 0.732, 95% CI: 0.444 - 1.208), while, high heterogeneity among studies was found, I-squared index (I2) = 40.2%. After remove one study with high heterogeneity, the OR of the pooled recurrence rates of the total thyroidectomy and the non-total thyroidectomy groups was 0.786 (95% CI: 0.363 - 1.701), further suggesting no significant difference of the recurrence rate exists between two operation modes. Our meta-analysis demonstrated postoperative recurrence of PTMC is not reduced by total thyroidectomy, non-total thyroidectomy is also a good choice to treat PTMC patients.

MicroRNA-139 targets fibronectin 1 to inhibit papillary thyroid carcinoma progression

Thyroid cancer is the most common tumour of the endocrine system, and its incidence rate has markedly increased over the past several decades. Aberrantly expressed microRNAs (miRNAs) are reportedly involved in the formation and progression of papillary thyroid carcinoma (PTC) by regulating their target genes. Thus, miRNAs may be potential molecular biomarkers for the prediction and prognosis of PTC, and also as novel therapeutic targets for patients with PTC. miR-139 has recently been reported to be aberrantly expressed in several types of cancer. However, the expression levels, biological functions and the associated molecular mechanism of miR-139 in PTC have not been clearly elucidated. The results of the present study revealed that miR-139 expression was downregulated in PTC tissues and cell lines when compared with adjacent normal tissues and normal human thyroid cells, respectively. The restoration of miR-139 expression suppressed cellular proliferation and invasion in PTC in vitro. In addition, fibronectin 1 (FN1) was identified as a direct target of miR-139 in PTC. Furthermore, FN1 was highly expressed in PTC tissues and negatively associated with miR-139 expression. Moreover, the tumour-suppressive effects of miR-139 overexpression on PTC cells were ameliorated by ectopic FN1 expression. To the best of our knowledge, the present study is the first to demonstrate that miR-139 may serve as a tumour suppressor and serve important roles in inhibiting tumourigenesis by targeting FN1 in PTC cells.

A distinct variant of papillary thyroid carcinoma indicating familial adenomatous polyposis (FAP): a case report and brief review

BACKGROUND

Familial adenomatous polyposis (FAP) is an autosomal dominantly inherited intestinal polyposis syndrome with an incidence of about 1/8300 births and accounts for about 1% of all colorectal cancers. It has a spectrum of extra-intestinal manifestations including thyroid carcinoma which occur in 1-2% of affected. The cribriform morular variant (CMV) is a rare but distinct histological subtype of papillary thyroid carcinoma (PTC) associated with FAP. Most of the reported cases describe the above entity in the background of well-established FAP. We report a case where both entities presenting simultaneously in a previously undiagnosed patient with FAP without a family history of polyposis.

CASE PRESENTATION

A 24 year old Asian female presented to the surgical clinic with a goitre of eight months duration and recent onset of altered bowel habits with features of anaemia. She was previously healthy and there was no family history of adenomatous polyposis, colorectal carcinoma or thyroid neoplasms. Colonoscopy revealed large bowel polyposis and fine needle aspiration of thyroid revealed a smear suspicious for malignancy. She underwent total thyroidectomy which revealed CMV PTC. Histology was characterized by a prominent cribriform pattern of growth with interspersed cell clusters arranged as morules along with papillary structures which are the key features of this subtype.

CONCLUSION

Diagnosis of CMV warrants ruling out of underlying FAP, irrespective of family history or gastrointestinal symptoms.

A detailed clinicopathologic study of ALK-translocated papillary thyroid carcinoma

Pathogenic ALK translocations have been reported in papillary thyroid carcinoma (PTC). We developed and validated a screening algorithm based on immunohistochemistry (IHC), followed by fluorescence in situ hybridization (FISH) in IHC-positive cases to identify ALK-rearranged PTC. IHC and FISH were performed in a cohort of 259 thyroid carcinomas enriched for aggressive variants. IHC was positive in 8 cases, 6 confirmed translocated by FISH (specificity 75%). All 251 IHC-negative cases were FISH negative (sensitivity 100%). Having validated this approach, we performed screening IHC, followed by FISH in IHC-positive cases in an expanded cohort. ALK translocations were identified in 11 of 498 (2.2%) of all consecutive unselected PTCs and 3 of 23 (13%) patients with diffuse sclerosing variant PTCs. No ALK translocations were identified in 36 PTCs with distant metastases, 28 poorly differentiated (insular) carcinomas, and 20 anaplastic carcinomas. All 14 patients with ALK translocations were female (P=0.0425), and translocations occurred at a younger age (mean 38 vs. 48 y, P=0.0289 in unselected patients). ALK translocation was an early clonal event present in all neoplastic cells and mutually exclusive with BRAF^V600E mutation. ALK translocation was not associated with aggressive clinicopathologic features (size, stage, metastasis, vascular invasion, extrathyroidal extension, multifocality, risk for recurrence, radioiodine resistance). We conclude that 2.2% of PTCs are ALK-translocated and can be identified by screening IHC followed by FISH. ALK translocations may be more common in young females and diffuse sclerosing variant PTC but do not connote more aggressive disease.

Risk factors influencing the recurrence of papillary thyroid carcinoma: a systematic review and meta-analysis

OBJECTIVE

To evaluate the risk factors influencing the recurrence of papillary thyroid carcinoma.

METHODS

This meta-analysis used MEDLINE (PubMed), EMBASE and CNKI including all cohort studies reporting the risk factors influencing the recurrence after the initial operation on PTC up to February 23, 2014. Software RevMan 5.2 was used for meta-analysis.

RESULTS

Thirteen studies with a total of 7048 patients were included in our meta-analysis. Of all variables, gender, extrathyroid extension, LNM, tumor size, distance metastasis, thyroid surgery types and 131-I given or not were significantly correlated with recurrence, While overall recurrence was similar between the group of ≤ 45 years and > 45 years, multifolicality and solitary. However, when stratified the participants by study location (ie, Asian including China, Korea, Japan, Western country including America, France, Italy, Australia), a statistically significant summary odds ratio for age were found in Western country but none in Asian.

CONCLUSION

The risk factors influencing recurrence includes male, extrathyroid extension, LNM, tumor size more than 2 cm, distance metastasis and subtotal thyroidectomy. However, selection of operation mode should be based on not only the recurrence but the comprehensive consideration of the clinical features.

P53 and expression of immunological markers may identify early stage thyroid tumors

Background. Besides its major role in cell proliferation, DNA repair, and apoptosis, functional p53 protein is involved in the induction of antitumor cytotoxic-T-cell activity against carcinoma cells. We aimed to investigate p53 and immune cell markers utility as diagnostic and prognostic markers of differentiated thyroid cancer (DTC). Methods. ACIS-III system was used to evaluate p53 and immune cell markers including tumor-associated macrophages (TAM); CD68 and tumor-infiltrating lymphocytes (TIL) subsets such as CD3, CD4, CD8, and CD20 in 206 thyroid carcinomas, 105 benign nodules, and 18 normal tissues. Also, TP53 was sequenced in 78 out of 164 patients with papillary thyroid carcinoma. Results. P53 expression was observed more frequently in malignant than in benign lesions (P < 0.0001) and helped discriminate follicular patterned lesions. In addition, p53 was more frequent in smaller (P = 0.0015), unique tumors (P = 0.0286), with thyroiditis (P = 0.0486) and without metastasis at diagnosis (P = 0.0201). TAM was more frequent in P53 negative tumors (P = 0.002). Infiltration of CD8+ TIL was found in 61.7% of P53 positive and 25.6% of P53 negative DTC (P < 0.001). Conclusions. We suggest that p53 and CD8+ TIL immune profile analysis might be useful in DTC.

miR-26a and its target CKS2 modulate cell growth and tumorigenesis of papillary thyroid carcinoma

Background

While many studies have shown that levels of miR-26a are lower in papillary thyroid carcinoma (PTC), the role and mechanism of miR-26a in PTC are unclear.

Method

We used database searches to select potential mRNA targets of miR-26a. Anti-miR-26a, miR-26a mimic, siRNA for CKS2 and their effects on cell growth, cell-cycle distribution and colony formation were evaluated. We also evaluate the over-expressed miR-26a in TPC-1 cells in severe combined immune-deficient mice. We used luciferase reporter assays, real-time PCR and western blot analysis to measure the expression and activity of miR-26a, CKS2, and related factors such as cyclin B1, cyclin A, cdk1, bcl-xl and Akt. Finally, we measured the relationship between the levels of miR-26a and CKS2 in PTC and normal thyroid tissues.

Results

Relative to normal thyroid tissues, miR-26a is consistently down-regulated in TPC specimens, and CKS2 was identified as a potential target. Up-regulated miR-26a expression or down-regulated CKS2 expression in TPC-1 and CGTH W3 cells lines caused G2 phase-arrest. Decreased miR-26a expression or increased CKS2 expression could have inverse function on PTC cell lines. CyclinB1, cyclinA, bcl-xl and AKt are indirectly regulated by miR-26a in a CKS2-dependent manner. Finally, CKS2 is overexpressed in PTC specimens relative to normal thyroid tissue, and a significant inverse correlation exists between miR-26a and CKS2 expression in clinical PTC specimens.

Conclusion

Our data indicate that miR-26a functions as a growth-suppressive miRNA in PTC, and that its suppressive effects are mediated mainly by repressing CKS2 expression.