Foxo3a drives proliferation in anaplastic thyroid carcinoma through transcriptional regulation of cyclin A1: a paradigm shift that impacts current therapeutic strategies

Anaplastic thyroid cancer: Genetic roles, targeted therapy, and immunotherapy

Anaplastic thyroid cancer (ATC) stands as the most formidable form of thyroid malignancy, presenting a persistent challenge in clinical management. Recent years have witnessed a gradual unveiling of the intricate genetic underpinnings governing ATC through next-generation sequencing. The emergence of this genetic landscape has paved the way for the exploration of targeted therapies and immunotherapies in clinical trials. Despite these strides, the precise mechanisms governing ATC pathogenesis and the identification of efficacious treatments demand further investigation. Our comprehensive review stems from an extensive literature search focusing on the genetic implications, notably the pivotal MAPK and PI3K-AKT-mTOR signaling pathways, along with targeted therapies and immunotherapies in ATC. Moreover, we screen and summarize the advances and challenges in the current diagnostic approaches for ATC, including the invasive tissue sampling represented by fine needle aspiration and core needle biopsy, immunohistochemistry, and 18F-fluorodeoxyglucose positron emission tomography/computed tomography. We also investigate enormous studies on the prognosis of ATC and outline independent prognostic factors for future clinical assessment and therapy for ATC. By synthesizing this literature, we aim to encapsulate the evolving landscape of ATC oncology, potentially shedding light on novel pathogenic mechanisms and avenues for therapeutic exploration.

CDK4 phosphorylation status and rational use for combining CDK4/6 and BRAF/MEK inhibition in advanced thyroid carcinomas

Background

CDK4/6 inhibitors (CDK4/6i) have been established as standard treatment against advanced Estrogen Receptor-positive breast cancers. These drugs are being tested against several cancers, including in combinations with other therapies. We identified the T172-phosphorylation of CDK4 as the step determining its activity, retinoblastoma protein (RB) inactivation, cell cycle commitment and sensitivity to CDK4/6i. Poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinomas, the latter considered one of the most lethal human malignancies, represent major clinical challenges. Several molecular evidence suggest that CDK4/6i could be considered for treating these advanced thyroid cancers.

Methods

We analyzed by two-dimensional gel electrophoresis the CDK4 modification profile and the presence of T172-phosphorylated CDK4 in a collection of 98 fresh-frozen tissues and in 21 cell lines. A sub-cohort of samples was characterized by RNA sequencing and immunohistochemistry. Sensitivity to CDK4/6i (palbociclib and abemaciclib) was assessed by BrdU incorporation/viability assays. Treatment of cell lines with CDK4/6i and combination with BRAF/MEK inhibitors (dabrafenib/trametinib) was comprehensively evaluated by western blot, characterization of immunoprecipitated CDK4 and CDK2 complexes and clonogenic assays.

Results

CDK4 phosphorylation was detected in all well-differentiated thyroid carcinomas (n=29), 19/20 PDTC, 16/23 ATC and 18/21 thyroid cancer cell lines, including 11 ATC-derived ones. Tumors and cell lines without phosphorylated CDK4 presented very high p16CDKN2A levels, which were associated with proliferative activity. Absence of CDK4 phosphorylation in cell lines was associated with CDK4/6i insensitivity. RB1 defects (the primary cause of intrinsic CDK4/6i resistance) were not found in 5/7 tumors without detectable phosphorylated CDK4. A previously developed 11-gene expression signature identified the likely unresponsive tumors, lacking CDK4 phosphorylation. In cell lines, palbociclib synergized with dabrafenib/trametinib by completely and permanently arresting proliferation. These combinations prevented resistance mechanisms induced by palbociclib, most notably Cyclin E1-CDK2 activation and a paradoxical stabilization of phosphorylated CDK4 complexes.

Conclusion

Our study supports further clinical evaluation of CDK4/6i and their combination with anti-BRAF/MEK therapies as a novel effective treatment against advanced thyroid tumors. Moreover, the complementary use of our 11 genes predictor with p16/KI67 evaluation could represent a prompt tool for recognizing the intrinsically CDK4/6i insensitive patients, who are potentially better candidates to immediate chemotherapy.

Promoting effects of calponin 3 on the growth of diffuse large B‑cell lymphoma cells

Diffuse large B‑cell lymphoma (DLBCL) is one of the most common types of lymphoma. Calponin 3 (CNN3) is a thin filament‑associated protein previously known to regulate smooth muscle contraction. Recent evidence illustrates its involvement in carcinogenesis; however, its roles in DLBCL remain unknown. CNN3 was found to be highly expressed in DLBCL specimens according to the online Gene Expression Profiling Interactive Analysis data. The aim of the present study was to investigate the roles of CNN3 in the progression of DLBCL. In vitro, the ectopic expression of CNN3 promoted the proliferation and G1/S transition of DLBCL cells, while its silencing led to opposite alterations. A similar tumor‑promoting role of CNN3 was also demonstrated by injecting nude mice with DLBCL cells over‑ or underexpressing CNN3. The results of dual‑luciferase reporter and chromatin immunoprecipitation assays revealed that forkhead box O3 (FOXO3), a known tumor suppressor in DLBCL, bound to the CNN3 promoter at ‑1955/‑1948 and ‑1190/‑1183, and suppressed the transcription of CNN3. The alterations induced by FOXO3 were partly blocked by CNN3 overexpression. On the whole, the present study demonstrates that CNN3, whose transcriptional activity is negatively regulated by FOXO3, contributes to the malignant behavior of DLBCL cells. The findings of the present study may provide novel diagnostic or therapeutic insight for DLBCL in clinical practice.

Lengthening the Guanidine-Aryl Linker of Phenylpyrimidinylguanidines Increases Their Potency as Inhibitors of FOXO3-Induced Gene Transcription

Increased FOXO3 nuclear localization is involved in neuroblastoma chemoresistance and tumor angiogenesis. Accordingly, FOXO3 inhibition is a promising strategy for boosting antitumor immune responses and suppressing FOXO3-mediated therapy resistance in cancer cells. However, no FOXO3 inhibitors are currently available for clinical use. Nevertheless, we have recently identified (4-propoxy)phenylpyrimidinylguanidine as a FOXO3 inhibitor in cancer cells in the low micromolar range. Here, we report the synthesis and structure-activity relationship study of a small library of its derivatives, some of which inhibit FOXO3-induced gene transcription in cancer cells in a submicromolar range and are thus 1 order of magnitude more potent than their parent compound. By NMR and molecular docking, we showed that these compounds differ in their interactions with the DNA-binding domain of FOXO3. These results may provide a foundation for further optimizing (4-propoxy)phenylpyrimidinylguanidine and developing therapeutics for inhibiting the activity of forkhead box (FOX) transcription factors and their interactions with other binding partners.

Tumor Suppressors Having Oncogenic Functions: The Double Agents

Cancer progression involves multiple genetic and epigenetic events, which involve gain-of-functions of oncogenes and loss-of-functions of tumor suppressor genes. Classical tumor suppressor genes are recessive in nature, anti-proliferative, and frequently found inactivated or mutated in cancers. However, extensive research over the last few years have elucidated that certain tumor suppressor genes do not conform to these standard definitions and might act as “double agents”, playing contrasting roles in vivo in cells, where either due to haploinsufficiency, epigenetic hypermethylation, or due to involvement with multiple genetic and oncogenic events, they play an enhanced proliferative role and facilitate the pathogenesis of cancer. This review discusses and highlights some of these exceptions; the genetic events, cellular contexts, and mechanisms by which four important tumor suppressors—pRb, PTEN, FOXO, and PML display their oncogenic potentials and pro-survival traits in cancer.

The role of FOXOs and autophagy in cancer and metastasis-Implications in therapeutic development

Autophagy is a highly conserved intracellular degradation process that plays a crucial role in cell survival and stress reactions as well as in cancer development and metastasis. Autophagy process involves several steps including sequestration, fusion of autophagosomes with lysosomes and degradation. Forkhead box O (FOXO) transcription factors regulate the expression of genes involved in cellular metabolic activity and signaling pathways of cancer growth and metastasis. Recent evidence suggests that FOXO proteins are also involved in autophagy regulation. The relationship among FOXOs, autophagy, and cancer has been drawing attention of many who work in the field. This study summarizes the role of FOXO proteins and autophagy in cancer growth and metastasis and analyzes their potential roles in cancer disease management.

Correlation of novel ALKATI with ALK immunohistochemistry and clinical outcomes in metastatic melanoma

AIMS

Recently, a novel isoform of anaplastic lymphoma kinase, with alternative transcription initiation (ALKATI ), has been described in melanoma and is susceptible to targeted ALK-inhibitor therapy. Clinical outcomes of patients with ALKATI mutated melanoma as well as correlation with immunohistochemical (IHC) methods have not yet been described.

METHODS AND RESULTS

Clinicopathological characteristics were abstracted for 324 patients with metastatic melanoma (MM). IHC, fluorescence in-situ hybridisation and RNA-based digital molecular analysis assays were performed on archival tissue from 173 stage III and 192 stage IV tumours. ALKATI was identified in 12.7 and 4.8% stage III and IV tumours, respectively. Discrete presentations of the ALKATI are seen: isolated ALKATI (n = 20) and mixed ALKATI (combined ALKATI and ALKWT ; n = 7). Isolated ALKWT expression (n = 4) was seen with no ALK fusions. Stage III patients showed improved survival with ALKATI expression compared to those with ALKWT or no expression [5-year survival 80, 95% confidence interval (CI) = 57-100% versus 43%, 95% CI = 34-55%, P = 0.013]. Clinicopathological characteristics were not statistically significant. Strong diffuse cytoplasmic staining of ALK IHC (n = 12) has a sensitivity of 52.2%, specificity 100%, PPV of 100% and NPV of 92.5% of detecting isolated ALKATI .

CONCLUSION

Presence of ALKATI is a good prognostic indicator in MM. ALK IHC and digital molecular analysis can be incorporated into MM evaluation to identify patients with ALKATI for targeted therapy.

Myoepithelioma-like Hyalinizing Epithelioid Tumors of the Hand With Novel OGT-FOXO3 Fusions

Myoepithelial tumors of soft tissue are uncommon neoplasms characterized histologically by spindle to epithelioid cells arranged in cords, nests, and/or reticular pattern with chondromyxoid to hyaline stroma, and genetically by rearrangement involving EWSR1 (among other less common genes) in about half of the cases. The diagnosis often requires immunostaining to confirm myoepithelial differentiation, most importantly the expression of epithelial markers and S100 protein and/or GFAP. However, there are cases wherein the morphology is reminiscent of myoepithelial tumors, while the immunophenotype falls short. Here, we report 2 highly similar myoepithelioma-like tumors arising in the hands of young adults. Both tumors were well-demarcated and composed of alternating cellular areas with palely eosinophilic hyaline stroma and scattered acellular zones of densely eosinophilic collagen deposition. The tumor cells were mainly epithelioid cells and arranged in cords or small nests. Vacuolated cells encircling hyaline matrix globules were focally prominent. A minor component of nonhyaline fibrous nodular areas composed of bland spindle cells and rich vasculature was also observed. Perivascular concentric spindle cell proliferation and perivascular hyalinization were present in some areas. The tumor cells were positive for CD34 and epithelial membrane antigen (focal) by immunostaining, while largely negative for cytokeratin, S100, GFAP, p63, GLUT1, and claudin-1. By RNA sequencing, a novel OGT-FOXO3 fusion gene was identified in case 1 and confirmed by reverse transcription polymerase chain reaction and fluorescence in situ hybridization in both cases. Sharing the unusual clinicopathologic features and the novel fusion, these 2 cases probably represent a distinct tumor entity, whose relationship with myoepithelial tumors and tumorigenic mechanisms exerted by the OGT-FOXO3 fusion remain to be studied.

Inhibition of PTEN Gene Expression by Small Interfering RNA on PI3K/Akt/FoxO3a Signaling Pathway in Human Nasopharyngeal Carcinoma

The objective of this article is to study the effect of inhibiting phosphatase and tensin homolog deleted chromatosome 10 gene on phosphoinositide 3-kinase/protein kinase B (Akt)/Forkhead homeobox O3a signaling pathway in human nasopharyngeal carcinoma HK-1 cells. Nasopharyngeal carcinoma HK-1 cell lines were divided into PTEN gene interference group (siPTEN), nonspecific small interfering RNA group (siNC), empty vector group (Vector), and no transfection control group (Normal). The mRNA and protein expression levels of PTEN, PI3K, p-Akt, and FoxO3a were detected by real-time fluorescence quantitative polymerase chain reaction and Western blot. Immunofluorescence was used to detect the subcellular localization of PTEN, PI3K, p-Akt, and FoxO3a in HK-1 cells. The proliferation of HK-1 cells was detected by MTT assay, and the apoptosis of HK-1 cells was detected by flow cytometry. Compared with the siNC group, the expression levels of PTEN, FoxO3a messenger RNA, and protein in the siPTEN group were significantly decreased (P < .05), while the expression levels of PI3K, p-Akt messenger RNA, and protein were significantly increased (P < .05). The growth rate of HK-1 cells in the siPTEN group was significantly higher than the siNC group (P < .05), while the apoptosis rate was significantly lower than that of the siNC group (P < .05). Small interfering RNA can inhibit the expression of PTEN in HK-1 cells, and PTEN can participate in the development of NPC by affecting PI3K/Akt/FoxO3a signaling pathway.

Cyclin A1 is associated with poor prognosis in oesophageal squamous cell carcinoma

Dysregulation of cyclin A1 (CCNA1) is implicated in the carcinogenesis, progression and metastasis of many types of solid tumours. In the present study, an mRNA single-channel expression profile chip experiment revealed that the CCNA1 mRNA levels in oesophageal squamous cell carcinoma (ESCC) were increased >10-fold compared with those in the adjacent non-cancer tissues. Reverse transcription-quantitative polymerase chain reaction and immunohistochemistry analyses were performed to additionally investigate the role of CCNA1 in the development and progression of ESCC in patients treated by radical resection of the oesophagus. The association between CCNA1 mRNA expression and the clinicopathological parameters of patients with ESCC was statistically analysed. The results indicated that upregulation of CCNA1 occurred in ~70% of patients with ESCC, and increased CCNA1 mRNA expression was significantly associated with advanced clinical stage, lymph node metastasis, invasiveness and poor clinical outcome, including disease-free survival and overall survival rates. Taken together, the data suggested that CCNA1 had an important function in ESCC development and progression, and may serve as a prognostic biomarker and therapeutic target in ESCC.

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.

Disease Gene Prediction by Integrating PPI Networks, Clinical RNA-Seq Data and OMIM Data

Disease gene prediction is a challenging task that has a variety of applications such as early diagnosis and drug development. The existing machine learning methods suffer from the imbalanced sample issue because the number of known disease genes (positive samples) is much less than that of unknown genes which are typically considered to be negative samples. In addition, most methods have not utilized clinical data from patients with a specific disease to predict disease genes. In this study, we propose a disease gene prediction algorithm (called dgSeq) by combining protein-protein interaction (PPI) network, clinical RNA-Seq data, and Online Mendelian Inheritance in Man (OMIN) data. Our dgSeq constructs differential networks based on rewiring information calculated from clinical RNA-Seq data. To select balanced sets of non-disease genes (negative samples), a disease-gene network is also constructed from OMIM data. After features are extracted from the PPI networks and differential networks, the logistic regression classifiers are trained. Our dgSeq obtains AUC values of 0.88, 0.83, and 0.80 for identifying breast cancer genes, thyroid cancer genes, and Alzheimer's disease genes, respectively, which indicates its superiority to other three competing methods. Both gene set enrichment analysis and predicted results demonstrate that dgSeq can effectively predict new disease genes.

Expression of the Forkhead box transcription factor Foxo3a in human periapical granulomas

It has been reported that Forkhead box transcription factor class O3a (Foxo3a) is expressed in rheumatoid arthritis, a chronic inflammatory condition accompanied by bone resorption, and plays a role in its pathology. However, it has remained unclear whether Foxo3a is involved in the pathogenesis of periapical granulomas. The present study was performed to compare the expression of Foxo3a in periapical granulomas and healthy gingival tissues. Samples were obtained surgically from patients, and subjected to hematoxylin-eosin staining for histopathologic diagnosis. Two-color immunofluorescence staining was also performed using antibodies against Foxo3a and markers for three types of inflammatory cells: neutrophils, T lymphocytes, and B lymphocytes. This revealed that Foxo3a was expressed in all three cell types in periapical granulomas but not in healthy gingival tissues. Foxo3a was expressed in 82.1%, 78.3%, and 77.5% of neutrophils, T lymphocytes, and B lymphocytes, respectively, and statistical analysis using the Kruskal-Wallis test followed by the Steel-Dwass test showed no significant difference of Foxo3a expression among the three cell types. Our results suggest that Foxo3a transcription factors may be involved in the pathogenesis of periapical granulomas.

Critical role of FOXO3a in carcinogenesis

FOXO3a is a member of the FOXO subfamily of forkhead transcription factors that mediate a variety of cellular processes including apoptosis, proliferation, cell cycle progression, DNA damage and tumorigenesis. It also responds to several cellular stresses such as UV irradiation and oxidative stress. The function of FOXO3a is regulated by a complex network of processes, including post-transcriptional suppression by microRNAs (miRNAs), post-translational modifications (PTMs) and protein-protein interactions. FOXO3a is widely implicated in a variety of diseases, particularly in malignancy of breast, liver, colon, prostate, bladder, and nasopharyngeal cancers. Emerging evidences indicate that FOXO3a acts as a tumor suppressor in cancer. FOXO3a is frequently inactivated in cancer cell lines by mutation of the FOXO3a gene or cytoplasmic sequestration of FOXO3a protein. And its inactivation is associated with the initiation and progression of cancer. In experimental studies, overexpression of FOXO3a inhibits the proliferation, tumorigenic potential, and invasiveness of cancer cells, while silencing of FOXO3a results in marked attenuation in protection against tumorigenesis. The role of FOXO3a in both normal physiology as well as in cancer development have presented a great challenge to formulating an effective therapeutic strategy for cancer. In this review, we summarize the recent findings and overview of the current understanding of the influence of FOXO3a in cancer development and progression.

Overexpression of Forkhead Box O3a and Its Association With Aggressive Phenotypes and Poor Prognosis in Human Hepatocellular Carcinoma

OBJECTIVES

Recent research has demonstrated that forkhead box O3a (FoxO3a) may function as an oncogenic transcription factor. We sought to validate the clinicopathologic significance of FoxO3a expression in hepatocellular carcinoma (HCC).

METHODS

Western blotting and immunohistochemistry were used to determine FoxO3a expression. In vitro cell proliferation and migration assays were performed in a HepG2 cell line.

RESULTS

FoxO3a was overexpressed in 121 (64.71%) cases of HCC. FoxO3a overexpression was associated with aggressive phenotypes of HCC, such as histologic grade (P < .001), stage (P = .031), and small vessel invasion (P < .001). FoxO3a overexpression was also correlated with poor disease-free survival in both univariate and multivariate survival analyses (P = .001 and P = .018, respectively). Downregulation of FoxO3a in a HepG2 cell line inhibited cell proliferation and migration.

CONCLUSIONS

These results suggest a role for FoxO3a in HCC progression and support the potential use as a prognostic biomarker.

FOXOs Maintaining the Equilibrium for Better or for Worse

A paradigm shift is emerging within the FOXO field and accumulating evidence indicates that we need to reappreciate the role of FOXOs, at least in cancer development. Here, we discuss the possibility that FOXOs are both tumor suppressors as well as promoters of tumor progression. This is mostly dependent on the biological context. Critical to this dichotomous role is the notion that FOXOs are central in preserving cellular homeostasis in redox control, genomic stability, and protein turnover. From this perspective, a paradoxical role in both suppressing and enhancing tumor progression can be reconciled. As many small molecules targeting the PI3K pathway are developed by big pharmaceutical companies and/or are in clinical trial, we will discuss what the consequences may be for the context-dependent role of FOXOs in tumor development in treatment options based on active PI3K signaling in tumors.

CPNE1 silencing inhibits the proliferation, invasion and migration of human osteosarcoma cells

Osteosarcoma (OS) is the most common primary malignancy of the bone affecting children and adolescents. Copine 1 (CPNE1) is a highly conserved calcium-dependent phospholipid-binding protein and may function in regulating signal transduction and membrane trafficking. In the present study, we investigated CPNE1 expression in osteosarcoma tissues and cells, and studied the effects of small interfering RNA (siRNA)-targeting CPNE1 on proliferation, metastasis and chemosensitivity of the osteosarcoma cells. The results demonstrated that CPNE1 was highly expressed in the osteosarcoma tissues and cell lines. Moreover, functional investigations confirmed that CPNE1 knockdown significantly inhibited cell proliferation, colony formation, invasion and metastasis in Saos-2 and HOS cells. Western blot analysis indicated that CPNE1 silencing downregulated the expression of many proteins associated with tumorigenesis and development, including Ras, MEK-1/2, WNT1, β-catenin, cyclin A1, IRAK2 and cIAP2. In addition, CPNE1 downregulation enhanced the sensitivity of Saos-2 cells towards cisplatin and adriamycin. The present study provides deep insight into the clinical use of lentiviral-mediated CPNE1 silencing for osteosarcoma therapy.

Carfilzomib potentiates CUDC-101-induced apoptosis in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is one of the most aggressive human malignancies, with no effective treatment currently available. Previously, we identified agents active against ATC cells, both in vitro and in vivo, using quantitative high-throughput screening of 3282 clinically approved drugs and small molecules. Here, we report that combining two of these active agents, carfilzomib, a second-generation proteasome inhibitor, and CUDC-101, a histone deacetylase and multi-kinase inhibitor, results in increased, synergistic activity in ATC cells. The combination of carfilzomib and CUDC-101 synergistically inhibited cellular proliferation and caused cell death in multiple ATC cell lines harboring various driver mutations observed in human ATC tumors. This increased anti-ATC effect was associated with a synergistically enhanced G2/M cell cycle arrest and increased caspase 3/7 activity induced by the drug combination. Mechanistically, treatment with carfilzomib and CUDC-101 increased p21 expression and poly (ADP-ribose) polymerase protein cleavage. Our results suggest that combining carfilzomib and CUDC-101 would offer an effective therapeutic strategy to treat ATC.

Overexpression of FoxO3a is associated with glioblastoma progression and predicts poor patient prognosis

Forkhead transcription factor FoxO3a has been reported to have ambiguous functions and distinct mechanisms in various solid tumors, including glioblastoma (GBM). Although a preliminary analysis of a small sample of patients indicated that FoxO3a aberrations in glioma might be related to aggressive clinical behavior, the clinical significance of FoxO3a in glioblastoma remains unclear. We investigated the expression of FoxO3a in a cohort of 91 glioblastoma specimens and analyzed the correlations of protein expression with patient prognosis. Furthermore, the functional impact of FoxO3a on GBM progression and the underlying mechanisms of FoxO3a regulation were explored in a series of in vitro and in vivo assays. FoxO3a expression was elevated in glioblastoma tissues, and high nuclear FoxO3a expression in human GBM tissues was associated with poor prognosis. Moreover, knockdown of FoxO3a significantly reduced the colony formation and invasion ability of GBM cells, whereas overexpression of FoxO3a promoted the colony formation and invasion ability. The results of in vivo GBM models further confirmed that FoxO3a knockdown inhibited GBM progression. More, the pro-oncogenic effects of FoxO3a in GBM were mediated by the activation of c-Myc, microtubule-associated protein 1 light chain 3 beta (LC3B) and Beclin1 in a mixed-lineage leukemia 2 (MLL2)-dependent manner. These findings suggest that high FoxO3a expression is associated with glioblastoma progression and that FoxO3a independently indicates poor prognosis in patients. FoxO3a might be a novel prognostic biomarker or a potential therapeutic target in glioblastoma.

Bioinformatics analysis of key genes and latent pathway interactions based on the anaplastic thyroid carcinoma gene expression profile

Anaplastic thyroid carcinoma (ATC) is an aggressive malignant disease in older adults with a high mortality rate. The present study aimed to examine several key genes and pathways, which are associated with ATC. The GSE33630 gene expression profile was downloaded from the Gene Expression Omnibus database, which included 11 ATC and 45 normal thyroid samples. The differentially expressed genes (DEGs) in ATC were identified using the Limma package in R. The Gene Ontology functions and Kyoto Encyclopedia of Genes and Genomes pathways of the selected DEGs were enriched using the Database for Annotation, Visualization and Integrated Discovery. A protein-protein interaction (PPI) network of the DEGs was constructed to select significant modules. Furthermore, a latent pathway interactive network was constructed to select the significant pathways associated with ATC. A total of 665 DEGs in the ATC samples were screened, and four significant modules were selected from the PPI network. The DEGs in the four modules were enriched in several functions and pathways. In addition, 29 significant pathways associated with ATC were selected, and he Toll-like receptor (TLR) signaling pathway, extracellular matrix (ECM)-receptor interaction and cytokine-cytokine interaction pathway were identified as important pathways. FBJ murine osteosarcoma viral oncogene homolog (FOS), chemokine C-X-C motif ligand 10 (CXCL10), collagen type V α1 (COL5A1) and chemokine (C-C motif) ligand 28 (CCL28) were the key DEGs involved in these significant pathways. The data obtained in the present study revealed that the TLR signaling pathway, ECM-receptor interaction and cytokine-cytokine receptor interaction pathway, and the FOS, CXCL10, COL5A1, COL11A1 and CCL28 genes have different roles in the progression of ATC, and these may be used as therapeutic targets for ATC.

Dual inhibition of HDAC and EGFR signaling with CUDC-101 induces potent suppression of tumor growth and metastasis in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is one of the most lethal human malignancies that currently has no effective therapy. We performed quantitative high-throughput screening (qHTS) in three ATC cell lines using 3,282 clinically approved drugs and drug candidates, and identified 100 active agents. Enrichment analysis of active compounds showed that inhibitors of EGFR and histone deacetylase (HDAC) were most active. Of these, the first-in-class dual inhibitor of EGFR, HER2 and HDACs, CUDC-101, had the highest efficacy and lower IC₅₀ than established drugs. We validated that CUDC-101 inhibited cellular proliferation and resulted in cell death by inducing cell cycle arrest and caspase-dependent apoptosis. CUDC-101 also inhibited cellular migration in vitro. Mechanistically, CUDC-101 inhibited MAPK signaling and histone deacetylation in ATC cell lines with multiple driver mutations present in human ATC. The anticancer effect of CUDC-101 was associated with increased expression of p21 and E-cadherin, and reduced expression of survivin, XIAP, β-catenin, N-cadherin, and Vimentin. In an in vivo mouse model of metastatic ATC, CUDC-101 inhibited tumor growth and metastases, and significantly prolonged survival. Response to CUDC-101 treatment in vivo was associated with increased histone 3 acetylation and reduced survivin expression. Our findings provide a preclinical basis to evaluate CUDC-101 therapy in ATC.

Cancer-testis antigen cyclin A1 is broadly expressed in ovarian cancer and is associated with prolonged time to tumor progression after platinum-based therapy

BACKGROUND

Cyclin A1 is essential for male gametopoiesis. In acute myeloid leukemia, it acts as a leukemia-associated antigen. Cyclin A1 expression has been reported in several epithelial malignancies, including testicular, endometrial, and epithelial ovarian cancer (EOC). We analyzed Cyclin A1 expression in EOC and its correlation with clinical features to evaluate Cyclin A1 as a T-cell target in EOC.

METHODS

Cyclin A1 mRNA expression in EOC and healthy tissues was quantified by microarray analysis and quantitative real-time PCR (qRT-PCR). Protein expression in clinical samples was assessed by immunohistochemistry (IHC) and was correlated to clinical features.

RESULTS

Cyclin A1 protein was homogeneously expressed in 43 of 62 grade 3 tumor samples and in 1 of 10 grade 2 specimens (p < 0.001). Survival analysis showed longer time to progression (TTP) among patients with at least moderate Cyclin A1 expression (univariate: p = 0.018, multivariate: p = 0.035). FIGO stage, grading, age, macroscopic residual tumor after debulking, and peritoneal carcinomatosis / distant metastasis had no impact on TTP or overall survival (OS).

CONCLUSION

Cyclin A1 is highly expressed in most EOCs. The mechanism behind the prolonged TTP in patients with high Cyclin A1 expression warrants further investigation. The frequent, selectively high expression of Cyclin A1 in EOC makes it a promising target for T-cell therapies.

Zinc deficiency impairs the renewal of hippocampal neural stem cells in adult rats: involvement of FoxO3a activation and downstream p27(kip1) expression

Zinc plays an important role in the development and maintenance of central neural system. Zinc deficiency has been known to alter normal brain function, whose molecular mechanism remains largely elusive. In the present study, we established a zinc deficiency-exposed rat model, and, using western blot and immunohistochemical analyses, found that the expression of FoxO3a and p27(kip1) was remarkably up-regulated in the rat brain hippocampus. Immunofluorescence assay showed that FOXO3a and p27(kip1) were significantly co-localized with nestin, the marker of neural stem cells (NSCs). Furthermore, we identified that the proportion of proliferating NSCs was markedly decreased in zinc-deficient rat hippocampaus. Using C17.2 neural stem cells, it was revealed that exposure to zinc chelator N,N,N',N'-tetrakis-(2-pyridylmethy) ethylenediamine induced the expression of FoxO3a and p27(kip1) , which coincided with reduced NSC proliferation. Furthermore, depletion of FoxO3a inhibited p27(kip1) expression and restored the growth of NSCs. On the basis of these data, we concluded that FoxO3a/p27(kip1) signaling might play a significant role in zinc deficiency-induced growth impairment of NSCs and consequent neurological disorders. We describe here that zinc deficiency induces the proliferative impairment of hippocampal neural stem cells partially through the activation of FOXO3a-p27 axis in rats. Neural progenitor cells exhibited significantly up-regulated expression of FOXO3a and p27 after zinc deficiency in vivo and in vitro. Depletion of FOXO3a ameliorates zinc deficiency-induced expression of p27 and growth impairment of neural stem cells. We provide novel insight into the mechanisms underlying zinc deficiency-induced neurological deficits.

Modeling anaplastic thyroid carcinoma in the mouse

Anaplastic thyroid carcinoma is the least common form of thyroid cancer; however, it accounts for the majority of deaths associated with this family of malignancies. A number of genetically engineered immunocompetent mouse models recapitulating the genetic and histological features of anaplastic thyroid cancer have been very recently generated and represent an invaluable tool to dissect the mechanisms involved in the progression from indolent, well-differentiated tumors to aggressive, undifferentiated carcinomas and to identify novel therapeutic targets. In this review, we focus on the relevant characteristics associated with these models and on what we have learned in terms of anaplastic thyroid cancer biology, genetics, and response to targeted therapy.

Altered gene expression in blood and sputum in COPD frequent exacerbators in the ECLIPSE cohort

Patients with chronic obstructive pulmonary disease (COPD) who are defined as frequent exacerbators suffer with 2 or more exacerbations every year. The molecular mechanisms responsible for this phenotype are poorly understood. We investigated gene expression profile patterns associated with frequent exacerbations in sputum and blood cells in a well-characterised cohort. Samples from subjects from the ECLIPSE COPD cohort were used; sputum and blood samples from 138 subjects were used for microarray gene expression analysis, while blood samples from 438 subjects were used for polymerase chain reaction (PCR) testing. Using microarray, 150 genes were differentially expressed in blood (>±1.5 fold change, p≤0.01) between frequent compared to non-exacerbators. In sputum cells, only 6 genes were differentially expressed. The differentially regulated genes in blood included downregulation of those involved in lymphocyte signalling and upregulation of pro-apoptotic signalling genes. Multivariate analysis of the microarray data followed by confirmatory PCR analysis identified 3 genes that predicted frequent exacerbations; B3GNT, LAF4 and ARHGEF10. The sensitivity and specificity of these 3 genes to predict the frequent exacerbator phenotype was 88% and 33% respectively. There are alterations in systemic immune function associated with frequent exacerbations; down-regulation of lymphocyte function and a shift towards pro-apoptosis mechanisms are apparent in patients with frequent exacerbations.

Cyclin A1 is a transcriptional target of PITX2 and overexpressed in papillary thyroid carcinoma

Physiological expression of cyclin A1, a unique cell cycle regulator essential for spermatogenesis, is predominantly restricted in male germ cells. Outstandingly, previous studies have also demonstrated the abnormal expression of cyclin A1 in various human tumors. How male germ cell-specific cyclin A1 is transcriptionally activated in tumor cells, however, is elusive. To begin to understand the molecular mechanisms governing the ectopic expression of cyclin A1, we searched for transcription factors and cis-regulatory DNA elements. We found that overexpression of PITX2, a paired-like homeodomain transcription factor and a downstream effector of Wnt/β-catenin signaling, resulted in upregulation of cyclin A1 in HEK293 cells and TPC-1 thyroid cancer cells. On the other hand, PITX2 knockdown in TPC-1 cells caused reduced cyclin A1. Promoter reporter assays with a series of deletion constructs determined that the DNA element from -102 to -96 bp of the cyclin A1 promoter is responsible for PITX2-induced gene expression. The result of chromatin immunoprecipitation revealed the occupancy of PITX2 on the cyclin A1 promoter. Taken together, these findings demonstrate that cyclin A1 is a transcriptional target of PITX2. Consistently, our immunohistochemistry result showed up-regulation of cyclin A1 in human papillary thyroid carcinoma, where overexpressed PITX2 has been endorsed in our recent report. Thus, our study provides new evidence on the regulation of cyclin A1 gene expression and offers a PITX2-cycin A1 pathway for cell cycle regulation.

Cadmium modifies the cell cycle and apoptotic profiles of human breast cancer cells treated with 5-fluorouracil

Industrialisation, the proximity of factories to cities, and human work activities have led to a disproportionate use of substances containing heavy metals, such as cadmium (Cd), which may have deleterious effects on human health. Carcinogenic effects of Cd and its relationship with breast cancer, among other tumours, have been reported. 5-Fluorouracil (5-FU) is a fluoropyrimidine anticancer drug used to treat solid tumours of the colon, breast, stomach, liver, and pancreas. The purpose of this work was to study the effects of Cd on cell cycle, apoptosis, and gene and protein expression in MCF-7 breast cancer cells treated with 5-FU. Cd altered the cell cycle profile, and its effects were greater when used either alone or in combination with 5-FU compared with 5-FU alone. Cd significantly suppressed apoptosis of MCF-7 cells pre-treated with 5-FU. Regarding gene and protein expression, bcl2 expression was mainly upregulated by all treatments involving Cd. The expression of caspase 8 and caspase 9 was decreased by most of the treatments and at all times evaluated. C-myc expression was increased by all treatments involving Cd, especially 5-FU plus Cd at the half time of treatment. Cd plus 5-FU decreased cyclin D1 and increased cyclin A1 expression. In conclusion, our results indicate that exposure to Cd blocks the anticancer effects of 5-FU in MCF-7 cells. These results could have important clinical implications in patients treated with 5-FU-based therapies and who are exposed to high levels of Cd.