Transcription Factor HOXA9 is Linked to the Calcification and Invasion of Papillary Thyroid Carcinoma

Effect of GATAD1 regulating the SRRM2 gene on recurrence of thyroid tumor and its molecular mechanism

Background

Thyroid blood vessels and nerves are rich, and their anatomical and physiological structures are complex. Surgery often fails to eradicate the tumor, which has a serious negative impact on the surgical outcomes and patient prognosis. Therefore, it is important to accurately predict the recurrence rate of thyroid cancer.

Methods

Based on bioinformatics analysis, the highly expressed transcription factors and differential genes in thyroid carcinoma (THCA) were obtained. Kaplan-Meier survival analysis was used to analyze the clinical effects of GATAD1 as well as SRRM2 on the recurrence of THCA patients. The effect of GATAD1 on SRRM2 expression was explored using cell experiments. Other experiments were conducted to reveal the interaction between SRRM2 and GATAD1 and their functions in THCA progression, such as cell proliferation and cell cycle.

Results

GATAD1 was overexpressed in recurrent THCA tissue compared with that in adjacent normal tissue. GATAD1 and SRRM2 were identified as the key risk factors for THCA recurrence as well as survival. Knockdown of GATAD1 and SRRM2 can inhibit THCA cell proliferation and arrest THCA cells in the G1 phase. Inhibiting GATAD1 decreased SRRM2 expression in THCA cells, whereas overexpressing GATAD1 had the opposite result. SRRM2 knockdown eliminated GATAD1-induced proliferation of THCA cells in vitro, indicating that GATAD1-induced THCA cell proliferation was dependent on increased SRRM2 expression.

Conclusions

We identified GATAD1 as an underlying diagnostic biomarker in THCA recurrence patients. The GATAD1-SRRM2 axis mediates human THCA recurrence progression and is an underlying target for THCA treatment.

Role of HOXA9 in solid tumors: mechanistic insights and therapeutic potential

HOXA9 functioning as a transcription factor is one of the members of HOX gene family, which governs multiple cellular activities by facilitating cellular signal transduction. In addition to be a driver in AML which has been widely studied, the role of HOXA9 in solid tumor progression has also received increasing attention in recent years, where the aberrant expression of HOXA9 is closely associated with the prognosis of patient. This review details the signaling pathways, binding partners, post-transcriptional regulation of HOXA9, and possible inhibitors of HOXA9 in solid tumors, which provides a reference basis for further study on the role of HOXA9 in solid tumors.

NR4A1 promotes LEF1 expression in the pathogenesis of papillary thyroid cancer

The morbidity of papillary thyroid cancer (PTC) is on the rise, but its pathogenesis is still poorly understood. NR4A1 is a transcription factor primarily involving a wide range of pathophysiological responses, but its relationship with PTC malignancy remains unclear. This study demonstrates that high NR4A1 expression is strongly associated with poor survival outcomes in PTC patients. The depletion of NR4A1 significantly inhibited the proliferation of PTC cells by negating the LEF1-mediated oncogenic alteration. Mechanistically, NR4A1 directly binds to the promoter region of LEF1 and leads to crosstalk with histone acetylation and DNA demethylation to transcriptionally upregulate LEF1 expression, subsequently promoting downstream growth-related genes expressions in PTC. In the light of our findings, NR4A1 may be an emerging driving factor in PTC pathogenesis and progression.

Transcription factor Sp2 promotes TGFB-mediated interstitial cell osteogenic differentiation in bicuspid aortic valves through a SMAD-dependent pathway

Calcification of the bicuspid aortic valve (BAV) involves differential expression of various RNA genes, which is achieved through complex regulatory networks that are controlled in part by transcription factors and microRNAs. We previously found that miR-195-5p regulates the osteogenic differentiation of valvular interstitial cells (VICs) by targeting the TGF-β pathway. However, the transcriptional regulation of miR-195-5p in calcified BAV patients is not yet clear. In this study, stenotic aortic valve tissues from patients with BAVs and tricuspid aortic valves (TAVs) were collected. Candidate transcription factors of miR-195-5p were predicted by bioinformatics analysis and tested in diseased valves and in male porcine VICs. SP2 gene expression and the corresponding protein levels in BAV were significantly lower than those in TAV, and a low SP2 expression level environment in VICs resulted in remarkable increases in RNA expression levels of RUNX2, BMP2, collagen 1, MMP2, and MMP9 and the corresponding proteins. ChIP assays revealed that SP2 directly bound to the transcription promoter region of miR-195-5p. Cotransfection of SP2 shRNA and a miR-195-5p mimic in porcine VICs demonstrated that SP2 repressed SMAD7 expression via miR-195-5p, while knockdown of SP2 increased the mRNA expression of SMAD7 and the corresponding protein and attenuated Smad 2/3 expression. Immunofluorescence staining of diseased valves confirmed that the functional proteins of osteogenesis differentiation, including RUNX2, BMP2, collagen 1, and osteocalcin, were overexpressed in BAVs. In Conclusion, the transcription factor Sp2 is expressed at low levels in VICs from BAV patients, which has a negative impact on miR-195-5p expression by binding its promoter region and partially promotes calcification through a SMAD-dependent pathway.

miR-381-3p attenuates doxorubicin resistance in human anaplastic thyroid carcinoma via targeting homeobox A9

Abnormal microRNA (miR) expression has frequently been reported to be implicated in cancer-related drug resistance. Herein, we planned to investigate whether miR-381-3p contributes to doxorubicin (DOX) resistance in anaplastic thyroid carcinoma (ATC). DOX-resistant ATC tissues and cell lines were prepared to detect miR-381-3p and homeobox A9 (HOXA9) expression. CCK8, transwell and TUNEL assays were performed to evaluate cell proliferation, migration and invasion, and apoptosis in in vitro experiments. HOXA9 expression is intensively expressed in ATC tissues compared with benign thyroid tissues. Compared with parental ATC cell lines, HOXA9 protein expression is significantly up-regulated in DOX-resistant SW1736 and CAL62 cells. The knockdown of HOXA9 leads to growth inhibition and apoptosis of DOX-resistant SW1736 and CAL62 cells. Our results also indicate a significant decrease in miR-381-3p expression levels in DOX-resistant ATC tissues and cell lines. miR-381-3p may function as a tumour suppressor to impede proliferation, migration and invasion and induce apoptosis of DOX-resistant SW1736 and CAL62 cells by inhibiting HOXA9 protein expression. Our results present a novel signalling axis miR-381-3p/HOXA9 that mediates DOX resistance in ATC. miR-381-3p and HOXA9 may be promising molecular targets for preventing ATC progression and drug resistance.

A two-microRNA signature predicts the progression of male thyroid cancer

In various cancers, microRNAs (miRNAs) are abnormally expressed, including thyroid cancer (TC). In recent years, the incidence of TC has increased annually around the world. Compared with female patients, male TC patients are more likely to have a postoperative recurrence and lymph node metastasis, and hence need second treatments. However, the molecular biological processes underlying this phenomenon are not understood. Therefore, we collected data on miRNA expression and clinical information of male TC patients from The Cancer Genome Atlas (TCGA) database. Differentially expressed miRNAs were identified between male TC tissues and matched normal tissues. The Kaplan–Meier method, univariate and multivariate Cox regressions, and receiver operating characteristic curve analyses were performed to assess the association between miRNAs and the disease-free survival of male TC patients. Gene Ontology (GO) and the Kyoto Encyclopaedia of Gene and Genome (KEGG) enrichment analyses were then used to explore the function of miRNA target genes. Furthermore, we evaluated the ability of the miRNA biomarker to predict survival in female TC patients. As a result, a total of 118 differentially expressed miRNAs were identified, including 25 upregulated and 93 downregulated miRNAs. Among them, miR-451a and miR-16-1-3p were confirmed to be independent prognostic factors for the disease-free survival rate. The target genes of miR-451a and miR-16-1-3p were identified, and functional analysis showed that these genes were enriched in 25 Go and KEGG accessions, including cell signal transduction, motor adhesion, phagocytosis, regulation of transcription, cell proliferation, angiogenesis, etc. Neither miR-451a and miR-16-1-3p, nor a prediction model based on both miRNAs effectively predicted survival in female TC patients. In conclusion, both miR-451a and miR-16-1-3p may play important roles in the processes of male TC. The two-miRNA signature involving miR-1258 and miR-193a may serve as a novel prognostic biomarker for male TC patients.

Silencing long non-coding RNA DLX6-AS1 or restoring microRNA-193b-3p enhances thyroid carcinoma cell autophagy and apoptosis via depressing HOXA1

Long non‐coding RNA DLX6 antisense RNA 1 (DLX6‐AS1) lists a critical position in thyroid carcinoma (TC) development. However, the overall comprehension about DLX6‐AS1, microRNA (miR)‐193b‐3p and homeobox A1 (HOXA1) in TC is not thoroughly enough. Concerning to this, this work is pivoted on DLX6‐AS1/miR‐193b‐3p/HOXA1 axis in TC cell growth and autophagy. TC tissues and adjacent normal thyroid tissues were collected, in which expression of DLX6‐AS1, miR‐193b‐3p and HOXA1 was tested, together with their interactions. TC cells were transfected with DLX6‐AS1/miR‐193b‐3p‐related oligonucleotides or plasmids to test cell growth and autophagy. Tumorigenesis in nude mice was observed. DLX6‐AS1 and HOXA1 were up‐regulated, and miR‐193b‐3p was down‐regulated in TC. Depleted DLX6‐AS1 or restored miR‐193b‐3p disturbed cell growth and promoted autophagy. DLX6‐AS1 targeted miR‐193b‐3p and positively regulated HOXA1. miR‐193b‐3p inhibition mitigated the impaired tumorigenesis induced by down‐regulated DLX6‐AS1. Tumorigenesis in nude mice was consistent with that in cells. It is clear that DLX6‐AS1 depletion hinders TC cell growth and promotes autophagy via up‐regulating miR‐193b‐3p and down‐regulating HOXA1.

Molecular Aspects and Prognostic Significance of Microcalcifications in Human Pathology: A Narrative Review

The presence of calcium deposits in human lesions is largely used as imaging biomarkers of human diseases such as breast cancer. Indeed, the presence of micro- or macrocalcifications is frequently associated with the development of both benign and malignant lesions. Nevertheless, the molecular mechanisms involved in the formation of these calcium deposits, as well as the prognostic significance of their presence in human tissues, have not been completely elucidated. Therefore, a better characterization of the biological process related to the formation of calcifications in different tissues and organs, as well as the understanding of the prognostic significance of the presence of these calcium deposits into human tissues could significantly improve the management of patients characterized by microcalcifications associated lesions. Starting from these considerations, this narrative review highlights the most recent histopathological and molecular data concerning the formation of calcifications in breast, thyroid, lung, and ovarian diseases. Evidence reported here could deeply change the current point of view concerning the role of ectopic calcifications in the progression of human diseases and also in the patients’ management. In fact, the presence of calcifications can suggest an unfavorable prognosis due to dysregulation of normal tissues homeostasis.

Molecular Aspects of Thyroid Calcification

In thyroid cancer, calcification is mainly present in classical papillary thyroid carcinoma (PTC) and in medullary thyroid carcinoma (MTC), despite being described in benign lesions and in other subtypes of thyroid carcinomas. Thyroid calcifications are classified according to their diameter and location. At ultrasonography, microcalcifications appear as hyperechoic spots ≤ 1 mm in diameter and can be named as stromal calcification, bone formation, or psammoma bodies (PBs), whereas calcifications > 1 mm are macrocalcifications. The mechanism of their formation is still poorly understood. Microcalcifications are generally accepted as a reliable indicator of malignancy as they mostly represent PBs. In order to progress in terms of the understanding of the mechanisms behind calcification occurring in thyroid tumors in general, and in PTC in particular, we decided to use histopathology as the basis of the possible cellular and molecular mechanisms of calcification formation in thyroid cancer. We explored the involvement of molecules such as runt-related transcription factor-2 (Runx-2), osteonectin/secreted protein acidic and rich in cysteine (SPARC), alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteopontin (OPN) in the formation of calcification. The present review offers a novel insight into the mechanisms underlying the development of calcification in thyroid cancer.