BUB1/KIF14 complex promotes anaplastic thyroid carcinoma progression by inducing chromosome instability.

Chromosome instability (CIN) is a common contributor driving the formation and progression of anaplastic thyroid cancer (ATC), but its mechanism remains unclear. The BUB1 mitotic checkpoint serine/threonine kinase (BUB1) is responsible for the alignment of mitotic chromosomes, which has not been thoroughly studied in ATC. Our research demonstrated that BUB1 was remarkably upregulated and closely related to worse progression-free survival. Knockdown of BUB1 attenuated cell viability, invasion, migration and induced cell cycle arrests, whereas overexpression of BUB1 promoted the cell cycle progression of papillary thyroid cancer cells. BUB1 knockdown remarkably repressed tumour growth and tumour formation of nude mice with ATC xenografts and suppressed tumour metastasis in a zebrafish xenograft model. Inhibition of BUB1 by its inhibitor BAY-1816032 also exhibited considerable anti-tumour activity. Further studies showed that enforced expression of BUB1 evoked CIN in ATC cells. BUB1 induced CIN through phosphorylation of KIF14 at serine1292 (Ser1292 ). Overexpression of the KIF14ΔSer1292 mutant was unable to facilitate the aggressiveness of ATC cells when compared with that of the wild type. Collectively, these findings demonstrate that the BUB1/KIF14 complex drives the aggressiveness of ATC by inducing CIN.

Targeting DEP domain containing 1 in anaplastic thyroid carcinoma: Implications for stemness regulation and malignant phenotype suppression.

Background: Anaplastic thyroid carcinoma (ATC), a rare but highly aggressive endocrine malignancy, is characterized by a significant presence of cancer stem-like cells (CSCs). These CSCs, known for their self-renewal and differentiation capacities, contribute to various aggressive tumor properties, including recurrence, metastasis, heterogeneity, multidrug resistance, and radiation resistance. Despite their critical role, the regulatory mechanisms of CSCs in ATC remain poorly elucidated, posing challenges in effectively targeting these cells for treatment. Methods: To delve into this, we employed the single sample gene set enrichment analysis (ssGSEA) algorithm to evaluate the stemness of samples in combined datasets. Samples were then classified into high and low stemness subgroups based on their average stemness scores. Differential gene expression between these subgroups was analyzed. We further explored the association of candidate genes with patient prognosis. Additionally, we conducted gene set enrichment analysis (GSEA) and a series of cell biology experiments to validate the role of DEP domain-containing protein 1 (DEPDC1) in fostering CSC-like traits and regulating the malignant phenotypes of ATC. Results: Our investigation demonstrated that DEPDC1 was significantly upregulated in CSCs and is abundantly expressed in ATC tissues. In vitro assays revealed that knockdown of DEPDC1 markedly inhibited tumor sphere formation and attenuated the proliferation, invasion, and migration of ATC cells. This silencing also resulted in reduced expression of stemness markers associated with CSCs. Furthermore, our GSEA findings linked high DEPDC1 expression to cell cycle progression and the maintenance of tumor cell stemness, with DEPDC1 knockdown disrupting these signaling pathways. Collectively, our results position DEPDC1 as a pivotal regulator of CSC-like characteristics in ATC, where aberrant DEPDC1 expression amplifies stemness properties and fuels the cancer's aggressive behavior. Consequently, DEPDC1 emerges as a promising therapeutic target for ATC management. In summary, this study underscores the pivotal role of DEPDC1 in modulating CSC-like features in ATC, offering new avenues for targeted therapy in this challenging malignancy.

Immunological characteristics of immunogenic cell death genes and malignant progression driving roles of TLR4 in anaplastic thyroid carcinoma.

Anaplastic thyroid carcinoma (ATC) was a rare malignancy featured with the weak immunotherapeutic response. So far, disorders of immunogenic cell death genes (ICDGs) were identified as the driving factors in cancer progression, while their roles in ATC remained poorly clear. Datasets analysis identified that most ICDGs were high expressed in ATC, while DE-ICDGs were located in module c1_112, which was mainly enriched in Toll-like receptor signalings. Subsequently, the ICD score was established to classify ATC samples into the high and low ICD score groups, and function analysis indicated that high ICD score was associated with the immune characteristics. The high ICD score group had higher proportions of specific immune and stromal cells, as well as increased expression of immune checkpoints. Additionally, TLR4, ENTPD1, LY96, CASP1 and PDIA3 were identified as the dynamic signature in the malignant progression of ATC. Notably, TLR4 was significantly upregulated in ATC tissues, associated with poor prognosis. Silence of TLR4 inhibited the proliferation, metastasis and clone formation of ATC cells. Eventually, silence of TLR4 synergistically enhanced paclitaxel-induced proliferation inhibition, apoptosis, CALR exposure and release of ATP. Our findings highlighted that the aberrant expression of TLR4 drove the malignant progression of ATC, which contributed to our understanding of the roles of ICDGs in ATC.

ISG15 and ISGylation modulates cancer stem cell-like characteristics in promoting tumor growth of anaplastic thyroid carcinoma.

BACKGROUND: Anaplastic thyroid carcinoma (ATC) was a rare and extremely malignant endocrine cancer with the distinct hallmark of high proportion of cancer stem cell-like characteristics. Therapies aiming to cancer stem-like cells (CSCs) were emerging as a new direction in cancer treatment, but targeting ATC CSCs remained challenging, mainly due to incomplete insights of the regulatory mechanism of CSCs. Here, we unveiled a novel role of ISG15 in the modulation of ATC CSCs. METHODS: The expression of ubiquitin-like proteins were detected by bioinformatics and immunohistochemistry. The correlation between ISG15 expression and tumor stem cells and malignant progression of ATC was analyzed by single-cell RNA sequence from the Gene Expression Omnibus. Flow cytometry combined with immunofluorescence were used to verify the enrichment of ISG15 and ISGyaltion in cancer stem cells. The effect and mechanism of ISG15 and KPNA2 on cancer stem cell-like characteristics of ATC cells were determined by molecular biology experiments. Mass spectrometry combined with immunoprecipitation to screen the substrates of ISG15 and validate its ISGylation modification. Nude mice and zebrafish xenograft models were utilized to demonstrate that ISG15 regulates stem cell characteristics and promotes malignant progression of ATC. RESULTS: We found that among several ubiquitin proteins, only ISG15 was aberrantly expressed in ATC and enriched in CSCs. Single-cell sequencing analysis revealed that abnormal expression of ISG15 were intensely associated with stemness and malignant cells in ATC. Inhibition of ISG15 expression dramatically attenuated clone and sphere formation of ATC cells, and facilitated its sensitivity to doxorubicin. Notably, overexpression of ISGylation, but not the non-ISGylation mutant, effectively reinforced cancer stem cell-like characteristics. Mechanistically, ISG15 mediated the ISGylation of KPNA2 and impeded its ubiquitination to promote stability, further maintaining cancer stem cell-like characteristics. Finally, depletion of ISG15 inhibited ATC growth and metastasis in xenografted mouse and zebrafish models. CONCLUSION: Our studies not only provided new insights into potential intervention strategies targeting ATC CSCs, but also uncovered the novel biological functions and mechanisms of ISG15 and ISGylation for maintaining ATC cancer stem cell-like characteristics.

A signature of circadian rhythm genes in driving anaplastic thyroid carcinoma malignant progression.

BACKGROUND: Anaplastic thyroid carcinoma (ATC) was a rare and extremely malignant endocrine cancer. Recently, dysregulation of circadian rhythm genes was demonstrated to play an essential role in tumor progression, while its exact role and mechanism in ATC remained poorly clear. METHODS: 4 ATC-related datasets were integrated to screen for differentially expressed circadian rhythm genes (DE-CRGs). Thereafter, Multiscale Embedded Gene Co-expression Network Analysis (MEGENA) and network enrichment analysis were conducted to investigate the dynamic characteristics of circadian rhythm genes. Next, Lasso-logistic model and immunohistochemistry were applied for determining the candidates. Finally, cell biological experiments and gene set enrichment analysis (GSEA) were used to confirm the roles of NPAS2 in ATC. RESULTS: 25 DE-CRGs were firstly identified in ATC. These DE-CRGs mainly regulated mitotic nuclear division, cytokinesis and DNA replication signals. Notably, NPAS2, CSNK1E, NAMPT, TYMS, SERPINE1, TOP2A, JUN, EGR3 and HEBP1 were identified as the dynamic signature in the malignant progression of ATC, which were confirmed by prognostic analysis. Furthermore, NPAS2 was found to be significantly up-regulated in ATC through clinical samples and cell experiments. Silencing NPAS2 effectively inhibited the proliferation, migration and invasion of ATC cells. GSEA showed that high expression of NPAS2 was mainly associated with cell cycle and focal adhesion, and silencing of NPAS2 suppressed these signals in our experiments. CONCLUSIONS: In summary, we found a dynamic 9-DE-CRGs signature in ATC. And the aberrant expression of NPAS2 drove the malignant phenotypes of ATC, which facilitated to deepen our understanding of the roles of circadian rhythm genes in ATC.