Tbx3 is a downstream target of the Wnt/beta-catenin pathway and a critical mediator of beta-catenin survival functions in liver cancer

Proteostatic reactivation of the developmental transcription factor TBX3 drives BRAF/MAPK-mediated tumorigenesis

MAPK pathway-driven tumorigenesis, often induced by BRAFV600E, relies on epithelial dedifferentiation. However, how lineage differentiation events are reprogrammed remains unexplored. Here, we demonstrate that proteostatic reactivation of developmental factor, TBX3, accounts for BRAF/MAPK-mediated dedifferentiation and tumorigenesis. During embryonic development, BRAF/MAPK upregulates USP15 to stabilize TBX3, which orchestrates organogenesis by restraining differentiation. The USP15-TBX3 axis is reactivated during tumorigenesis, and Usp15 knockout prohibits BRAFV600E-driven tumor development in a Tbx3-dependent manner. Deleting Tbx3 or Usp15 leads to tumor redifferentiation, which parallels their overdifferentiation tendency during development, exemplified by disrupted thyroid folliculogenesis and elevated differentiation factors such as Tpo, Nis, Tg. The clinical relevance is highlighted in that both USP15 and TBX3 highly correlates with BRAFV600E signature and poor tumor prognosis. Thus, USP15 stabilized TBX3 represents a critical proteostatic mechanism downstream of BRAF/MAPK-directed developmental homeostasis and pathological transformation, supporting that tumorigenesis largely relies on epithelial dedifferentiation achieved via embryonic regulatory program reinitiation.

PAX1 represses canonical Wnt signaling pathway and plays dual roles during endoderm differentiation

BACKGROUND

Paired box 1 (PAX1) is a transcription factor and essential for the development of pharyngeal pouches-derived tissues, including thymus. PAX1 mutations are identified in Severe Combined Immunodeficiency (SCID) patients with Otofaciocervical Syndrome Type 2 (OTFCS2). However, despite the critical roles of PAX1 in embryonic development and diseases, detailed insights into its molecular mode of action are critically missing.

METHODS

The repressing roles of PAX1 and SCID associated mutants on Wnt signaling pathway were investigated by luciferase reporter assays, qRT-PCR and in situ hybridization in HEK293FT, HCT116 cells and zebrafish embryos, respectively. Co-immunoprecipitation (co-IP) and western blotting assays were carried out to identify the molecular mechanisms underlying PAX1's role on Wnt signaling pathway. hESC based endoderm differentiation, flow cytometry, high-throughput sequencing data analysis, and qRT-PCR assays were utilized to determine the roles of PAX1 during endoderm differentiation.

RESULTS

Here, we show that PAX1 represses canonical Wnt signaling pathway in vertebrate cells. Mechanically, PAX1 competes with SUMO E3 ligase PIASy to bind to TCF7L2, thus perturbing TCF7L2 SUMOylation level, further reducing its transcriptional activity and protein stability. Moreover, we reveal that PAX1 plays dual roles in hESC-derived definitive and foregut/pharyngeal endoderm cells, which give rise to the thymus epithelium, by inhibiting Wnt signaling. Importantly, our data show PAX1 mutations found in SCID patients significantly compromise the suppressing ability of PAX1 on Wnt signaling.

CONCLUSIONS

Our study presents a novel molecular mode of action of PAX1 in regulation of canonical Wnt signaling and endoderm differentiation, thus providing insights for the molecular basis of PAX1 associated SCID, offering better understanding of the behavior of PAX1 in embryogenesis.

The time-resolved genomic impact of Wnt/β-catenin signaling

Wnt signaling orchestrates gene expression via its effector, β-catenin. However, it is unknown whether β-catenin binds its target genomic regions simultaneously and how this impacts chromatin dynamics to modulate cell behavior. Using a combination of time-resolved CUT&RUN against β-catenin, ATAC-seq, and perturbation assays in different cell types, we show that Wnt/β-catenin physical targets are tissue-specific, β-catenin "moves" on different loci over time, and its association to DNA accompanies changing chromatin accessibility landscapes that determine cell behavior. In particular, Wnt/β-catenin progressively shapes the chromatin of human embryonic stem cells (hESCs) as they undergo mesodermal differentiation, a behavior that we define as "plastic." In HEK293T cells, on the other hand, Wnt/β-catenin drives a transient chromatin opening, followed by re-establishment of the pre-stimulation state, a response that we define as "elastic." Future experiments shall assess whether other cell communication mechanisms, in addition to Wnt signaling, are ruled by time, cellular idiosyncrasies, and chromatin constraints. A record of this paper's transparent peer review process is included in the supplemental information.

Aberrant LYZ expression in tumor cells serves as the potential biomarker and target for HCC and promotes tumor progression via csGRP78

Hepatocellular carcinoma (HCC) takes the predominant malignancy of hepatocytes with bleak outcomes owing to high heterogeneity among patients. Personalized treatments based on molecular profiles will better improve patients' prognosis. Lysozyme (LYZ), a secretory protein with antibacterial function generally expressed in monocytes/macrophages, has been observed for the prognostic implications in different types of tumors. However, studies about the explicit applicative scenarios and mechanisms for tumor progression are still quite limited, especially for HCC. Here, based on the proteomic molecular classification data of early-stage HCC, we revealed that the LYZ level was elevated significantly in the most malignant HCC subtype and could serve as an independent prognostic predictor for HCC patients. Molecular profiles of LYZ-high HCCs were typical of those for the most malignant HCC subtype, with impaired metabolism, along with promoted proliferation and metastasis characteristics. Further studies demonstrated that LYZ tended to be aberrantly expressed in poorly differentiated HCC cells, which was regulated by STAT3 activation. LYZ promoted HCC proliferation and migration in both autocrine and paracrine manners independent of the muramidase activity through the activation of downstream protumoral signaling pathways via cell surface GRP78. Subcutaneous and orthotopic xenograft tumor models indicated that targeting LYZ inhibited HCC growth markedly in NOD/SCID mice. These results propose LYZ as a prognostic biomarker and therapeutic target for the subclass of HCC with an aggressive phenotype.

Role of T-box transcription factor 3 in gastric cancers

The expression of T-box transcription factor 3 (TBX3) has been identified in various cancers, including gastric cancers. Its role in breast cancers and melanomas has been intensively studied, and its contribution to the progression of cancers through suppressing senescence and promoting epithelial-mesenchymal transition has been reported. Recent reports on the role of TBX3 in gastric cancers have implied its involvement in gastric carcinogenesis. Considering its pivotal role in the initiation and progression of cancers, TBX3 could be a promising therapeutic target for gastric cancers.

The landscape of immune dysregulation in Crohn's disease revealed through single-cell transcriptomic profiling in the ileum and colon

Crohn's disease (CD) is a chronic gastrointestinal disease that is increasing in prevalence worldwide. CD is multifactorial, involving the complex interplay of genetic, immune, and environmental factors, necessitating a system-level understanding of its etiology. To characterize cell-type-specific transcriptional heterogeneity in active CD, we profiled 720,633 cells from the terminal ileum and colon of 71 donors with varying inflammation status. Our integrated datasets revealed organ- and compartment-specific responses to acute and chronic inflammation; most immune changes were in cell composition, whereas transcriptional changes dominated among epithelial and stromal cells. These changes correlated with endoscopic inflammation, but small and large intestines exhibited distinct responses, which were particularly apparent when focusing on IBD risk genes. Finally, we mapped markers of disease-associated myofibroblast activation and identified CHMP1A, TBX3, and RNF168 as regulators of fibrotic complications. Altogether, our results provide a roadmap for understanding cell-type- and organ-specific differences in CD and potential directions for therapeutic development.

The role and mechanism of claudins in cancer

Claudins are a tetraspan membrane protein multigene family that plays a structural and functional role in constructing tight junctions. Claudins perform crucial roles in maintaining cell polarity in epithelial and endothelial cell sheets and controlling paracellular permeability. In the last two decades, increasing evidence indicates that claudin proteins play a major role in controlling paracellular permeability and signaling inside cells. Several types of claudins are dysregulated in various cancers. Depending on where the tumor originated, claudin overexpression or underexpression has been shown to regulate cell proliferation, cell growth, metabolism, metastasis and cell stemness. Epithelial-to-mesenchymal transition is one of the most important functions of claudin proteins in disease progression. However, the exact molecular mechanisms and signaling pathways that explain why claudin proteins are so important to tumorigenesis and progression have not been determined. In addition, claudins are currently being investigated as possible diagnostic and treatment targets. Here, we discuss how claudin-related signaling pathways affect tumorigenesis, tumor progression, and treatment sensitivity.

Single-cell spatial transcriptomics reveals a dynamic control of metabolic zonation and liver regeneration by endothelial cell Wnt2 and Wnt9b

The conclusive identity of Wnts regulating liver zonation (LZ) and regeneration (LR) remains unclear despite an undisputed role of β-catenin. Using single-cell analysis, we identified a conserved Wnt2 and Wnt9b expression in endothelial cells (ECs) in zone 3. EC-elimination of Wnt2 and Wnt9b led to both loss of β-catenin targets in zone 3, and re-appearance of zone 1 genes in zone 3, unraveling dynamicity in the LZ process. Impaired LR observed in the knockouts phenocopied models of defective hepatic Wnt signaling. Administration of a tetravalent antibody to activate Wnt signaling rescued LZ and LR in the knockouts and induced zone 3 gene expression and LR in controls. Administration of the agonist also promoted LR in acetaminophen overdose acute liver failure (ALF) fulfilling an unmet clinical need. Overall, we report an unequivocal role of EC-Wnt2 and Wnt9b in LZ and LR and show the role of Wnt activators as regenerative therapy for ALF.

Suppressed Cellular Senescence Mediated by T-box3 in Aged Gastric Epithelial Cells may Contribute to Aging-related Carcinogenesis

Aging is a risk factor for cancers in various organs. Recent advances in the organoid culturing system have made it viable to investigate the influence of aging utilizing these mini organs. In this study, we aimed to examine the implications of aging for gastric carcinogenesis. Gastric organoids established from aged mice grew larger, proliferated vigorously, and survived longer than that from young mice. Because Wnt/β-catenin signaling was intensified in the aged organoids and because removal of Wnt-related factors diminished their proliferation, we investigated for Wnt target gene that contributed to enhanced proliferation and discovered that the aged organoids expressed the transcription factor T-box3 (Tbx3), which has been reported to suppress cellular senescence. Indeed, cellular senescence was suppressed in the aged organoids, and this resulted from enhanced G₂-M transition. As for the mechanism involved in the intensified Wnt/β-catenin signaling, we identified that Dickkopf3 (Dkk3) expression was reduced in the aged organoids due to methylation of the Dkk3 gene. Finally, the expression of TBX3 was enhanced in human atrophic gastritis and even more enhanced in human gastric cancers. In addition, its expression correlated positively with patients' age. These results indicated that the emergence of antisenescent property in aged gastric organoids due to enhanced Tbx3 expression led to accelerated cellular proliferation and organoid formation. Because the enhanced Tbx3 expression seen in aged gastric organoids was also observed in human gastric cancer tissues, this Dkk3-Wnt-Tbx3 pathway may be involved in aging-related gastric carcinogenesis.

Significance

This work provides an insight into the mechanism involved in aging-related gastric carcinogenesis through studies utilizing organoids established from young and aged murine stomachs.

Wnt signaling regulates hepatocyte cell division by a transcriptional repressor cascade

As a general model for cell cycle control, repressors keep cells quiescent until growth signals remove the inhibition. For S phase, this is exemplified by the Retinoblastoma (RB) protein and its inactivation. It was unknown whether similar mechanisms operate in the M phase. The Wnt signaling pathway is an important regulator of cell proliferation. Here, we find that Wnt induces expression of the transcription factor Tbx3, which in turn represses mitotic inhibitors E2f7 and E2f8 to permit mitotic progression. Such a cascade of transcriptional repressors may be a general mechanism for cell division control. These findings have implications for tissue homeostasis and disease, as the function for Wnt signaling in mitosis is relevant to its widespread role in stem cells and cancer.

Cell proliferation is tightly controlled by inhibitors that block cell cycle progression until growth signals relieve this inhibition, allowing cells to divide. In several tissues, including the liver, cell proliferation is inhibited at mitosis by the transcriptional repressors E2F7 and E2F8, leading to formation of polyploid cells. Whether growth factors promote mitosis and cell cycle progression by relieving the E2F7/E2F8-mediated inhibition is unknown. We report here on a mechanism of cell division control in the postnatal liver, in which Wnt/β-catenin signaling maintains active hepatocyte cell division through Tbx3, a Wnt target gene. The TBX3 protein directly represses transcription of E2f7 and E2f8, thereby promoting mitosis. This cascade of sequential transcriptional repressors, initiated by Wnt signals, provides a paradigm for exploring how commonly active developmental signals impact cell cycle completion.

Current Approaches in Hepatoblastoma-New Biological Insights to Inform Therapy

PURPOSE OF REVIEW

As the most common pediatric primary liver cancer with rising incidence, hepatoblastoma remains challenging to treat. Here, we review the current understanding of the biology of hepatoblastoma and discuss how recent advances may lead to new treatment modalities.

RECENT FINDINGS

Standard chemotherapy regimens including cisplatin, in addition to surgery, have led to high cure rates among patients with low stage hepatoblastoma; however, metastatic and relapsed disease continue to have poor outcomes. Recent genomics and functional studies in cell lines and mouse models have established a central role for the Wnt/β-catenin pathway in tumorigenesis. Targeted agents and immunotherapy approaches are emerging as potential treatment avenues. With recent gains in knowledge of the genomic and transcriptomic landscape of hepatoblastoma, new therapeutic mechanisms can now be explored to improve outcomes for metastatic and relapsed hepatoblastoma and to reduce the toxicity of current treatments.

T-box transcription factor 19 promotes hepatocellular carcinoma metastasis through upregulating EGFR and RAC1

The effect of targeted therapy for metastatic hepatocellular carcinoma (HCC) is still unsatisfactory. Exploring the underlying mechanism of HCC metastasis is favorable to provide new therapeutic strategies. T-box (TBX) transcription factor family genes, which are crucial regulators in embryo and organ development, are vital for regulating tumor initiation, growth and metastasis. Here we explored the role of TBX19 in HCC metastasis, which is one of the most upregulated TBX family genes in human HCC tissues. TBX19 expression was markedly upregulated in HCC tissues and elevated TBX19 expression predicted poor prognosis. Overexpression of TBX19 enhanced HCC metastasis through upregulating epidermal growth factor receptor (EGFR) and Rac family small GTPase 1 (RAC1) expression. Downregulation of EGFR and RAC1 inhibited TBX19-mediated HCC metastasis, while upregulation of EGFR and RAC1 restored inhibition of HCC metastasis mediated by TBX19 knockdown. Furthermore, epidermal growth factor (EGF)/EGFR signaling upregulated TBX19 expression via the extracellular signal-regulated kinase (ERK)/nuclear factor (NF)-kB axis. Besides, the combined application of EGFR inhibitor Erlotinib and RAC1 inhibitor NSC23766 markedly inhibited TBX19-mediated HCC metastasis. In HCC cohorts, TBX19 expression was positively associated with EGFR and RAC1 expression. Patients with positive coexpression of TBX19/EGFR or TBX19/RAC1 displayed the poorest prognosis. In conclusion, EGF/EGFR signaling upregulated TBX19 expression via ERK/NF-kB pathway and TBX19 fostered HCC metastasis by enhancing EGFR and RAC1 expression, which formed an EGF-TBX19-EGFR positive feedback loop. Targeting this signaling pathway may offer a potential therapeutic strategy to efficiently restrain TBX19-mediated HCC metastasis.

NOTUM promotes thermogenic capacity and protects against diet-induced obesity in male mice

We recently showed that NOTUM, a liver-secreted Wnt inhibitor, can acutely promote browning of white adipose. We now report studies of chronic overexpression of NOTUM in liver indicating that it protects against diet-induced obesity and improves glucose homeostasis in mice. Adeno-associated virus (AAV) vectors were used to overexpress GFP or mouse Notum in the livers of male C57BL/6J mice and the mice were fed an obesifying diet. After 14 weeks of high fat, high sucrose diet feeding, the AAV-Notum mice exhibited decreased obesity and improved glucose tolerance compared to the AAV-GFP mice. Gene expression and immunoblotting analysis of the inguinal fat and brown fat revealed increased expression of beige/brown adipocyte markers in the AAV-Notum group, suggesting enhanced thermogenic capacity by NOTUM. A β3 adrenergic receptor agonist-stimulated lipolysis test suggested increased lipolysis capacity by NOTUM. The levels of collagen and C–C motif chemokine ligand 2 (CCL2) in the epididymal white adipose tissue of the AAV-Notum mice were significantly reduced, suggesting decreased fibrosis and inflammation, respectively. RNA sequencing analysis of inguinal white adipose of 4-week chow diet-fed mice revealed a highly significant enrichment of extracellular matrix (ECM) functional cluster among the down-regulated genes in the AAV-Notum group, suggesting a potential mechanism contributing to improved glucose homeostasis. Our in vitro studies demonstrated that recombinant human NOTUM protein blocked the inhibitory effects of WNT3A on brown adipocyte differentiation. Furthermore, NOTUM attenuated WNT3A’s effects on upregulation of TGF-β signaling and its downstream targets. Overall, our data suggest that NOTUM modulates adipose tissue function by promoting thermogenic capacity and inhibiting fibrosis through inhibition of Wnt signaling.

TBX3 functions as a tumor suppressor downstream of activated CTNNB1 mutants during hepatocarcinogenesis

BACKGROUND & AIMS

Gain of function (GOF) mutations in the CTNNB1 gene are one of the most frequent genetic events in hepatocellular carcinoma (HCC). T-box transcription factor 3 (TBX3) is a liver-specific target of the Wnt/β-catenin pathway and thought to be an oncogene mediating activated β-catenin-driven HCC formation.

METHODS

We evaluated the expression pattern of TBX3 in human HCC specimens. Tbx3 was conditionally knocked out in murine HCC models by hydrodynamic tail vein injection of Cre together with c-Met and ΔN90-β-catenin (c-Met/β-catenin) in Tbx3^flox/flox mice. TBX3 was overexpressed in human HCC cell lines to investigate the functions of TBX3 in vitro.

RESULTS

A bimodal expression pattern of TBX3 in human HCC samples was detected: high expression of TBX3 in GOF CTNNB1 HCC and downregulation of TBX3 in non-CTNNB1 mutant tumors. High expression of TBX3 was associated with increased differentiation and decreased expression signatures of tumor growth. Using Tbx3^flox/flox mice, we found that ablation of Tbx3 significantly accelerates c-Met/β-catenin-driven HCC formation. Moreover, Tbx3(-) HCC demonstrated increased YAP/TAZ activity. The accelerated tumor growth induced by loss of TBX3 in c-Met/β-catenin mouse HCC was successfully prevented by overexpression of LATS2, which inhibited YAP/TAZ activity. In human HCC cell lines, overexpression of TBX3 inhibited HCC cell growth as well as YAP/TAZ activation. A negative correlation between TBX3 and YAP/TAZ target genes was observed in human HCC samples. Mechanistically, phospholipase D1 (PLD1), a known positive regulator of YAP/TAZ, was identified as a novel transcriptional target repressed by TBX3.

CONCLUSION

Our study suggests that TBX3 is induced by GOF CTNNB1 mutants and suppresses HCC growth by inactivating PLD1, thus leading to the inhibition of YAP/TAZ oncogenes.

LAY SUMMARY

TBX3 is a liver-specific target of the Wnt/β-catenin pathway and thought to be an oncogene in promoting liver cancer development. Herein, we demonstrate that TBX3 is in fact a tumor suppressor gene that restricts liver tumor growth. Strategies which increase TBX3 expression and/or activities may be effective for HCC treatment.

Exploiting within-breed variability in the autochthonous Reggiana breed identified several candidate genes affecting pigmentation-related traits, stature and udder defects in cattle

Autochthonous cattle breeds constitute important reservoirs of genetic diversity. Reggiana is an Italian local cattle breed reared in the north of Italy for the production of a mono‐breed Parmigiano–Reggiano cheese. Reggiana cattle usually have a classical solid red coat colour and pale muzzle. As part of the strategies designed for the sustainable conservation of this genetic resource, we investigated at the genome‐wise level the within‐breed detected variability of three pigmentation‐related traits (intensity of red coat colour, based on three classes – light/diluted, normal and dark; spotted patterns/piebaldism that sometime emerge in the breed; muzzle colour – pink/pale, grey and black), stature, presence/absence and number of supernumerary teats and teat length. A total of 1776 Reggiana cattle (about two‐thirds of the extant breed population) were genotyped with the GeneSeek GGP Bovine 150k SNP array and single‐marker and haplotype‐based GWASs were carried out. The results indicated that two main groups of genetic factors affect the intensity of red coat colour: darkening genes (including EDN3 and a few other genes) and diluting genes (including PMEL and a few other genes). Muzzle colour was mainly determined by MC1R gene markers. Piebaldism was mainly associated with KIT gene markers. Stature was associated with BTA6 markers upstream of the NCAPG–LCORL genes. Teat defects were associated with TBX3/TBX5, MCC and LGR5 genes. Overall, the identified genomic regions not only can be directly used in selection plans in the Reggiana breed, but also contribute to clarifying the genetic mechanisms involved in determining exterior traits in cattle.

Non-Canonical Functions of the ARF Tumor Suppressor in Development and Tumorigenesis

P14ARF (ARF; Alternative Reading Frame) is an extensively characterized tumor suppressor which, in response to oncogenic stimuli, mediates cell cycle arrest and apoptosis via p53-dependent and independent routes. ARF has been shown to be frequently lost through CpG island promoter methylation in a wide spectrum of human malignancies, such as colorectal, prostate, breast, and gastric cancers, while point mutations and deletions in the p14ARF locus have been linked with various forms of melanomas and glioblastomas. Although ARF has been mostly studied in the context of tumorigenesis, it has been also implicated in purely developmental processes, such as spermatogenesis, and mammary gland and ocular development, while it has been additionally involved in the regulation of angiogenesis. Moreover, ARF has been found to hold important roles in stem cell self-renewal and differentiation. As is often the case with tumor suppressors, ARF functions as a pleiotropic protein regulating a number of different mechanisms at the crossroad of development and tumorigenesis. Here, we provide an overview of the non-canonical functions of ARF in cancer and developmental biology, by dissecting the crosstalk of ARF signaling with key oncogenic and developmental pathways.

Reduction of T-Box 15 gene expression in tumor tissue is a prognostic biomarker for patients with hepatocellular carcinoma

Genome-wide analysis is widely applied to detect molecular alterations during oncogenesis and tumor progression. We analyzed DNA methylation profiles of hepatocellular carcinoma (HCC), and investigated the clinical role of most heypermethylated of tumor, encodes T-box 15 (TBX15), which was originally involved in mesodermal differentiation. We conducted a genome-wide analysis of DNA methylation of tumor and non-tumor tissue of 15 patients with HCC, and revealed TBX15 was the most hypermethylated gene of tumor (Beta-value in tumor tissue = 0.52 compared with non-tumor tissue). Another validation set, which comprised 58 HCC with radical resection, was analyzed to investigate the relationships between tumor phenotype and TBX15 mRNA expression. TBX15 mRNA levels in tumor tissues were significantly lower compared with those of nontumor tissues (p < 0.0001). When we assigned a cutoff value = 0.5-fold, the overall survival 5-year survival rates of the low-expression group (n = 17) were significantly shorter compared with those of the high-expression group (n = 41) (43.3% vs. 86.2%, p = 0.001). Multivariate analysis identified low TBX15 expression as an independent prognostic factor for overall and disease-free survival. Therefore, genome-wide DNA methylation profiling indicates that hypermethylation and reduced expression of TBX15 in tumor tissue represents a potential biomarker for predicting poor survival of patients with HCC.

Potential role of miR-214 in β-catenin gene expression within hepatocellular carcinoma

MicroRNAs (miRNAs) are important gene regulators whose dysregulations can be involved in tumorigenesis. β-catenin, the main agent in the Wnt/β-catenin pathway, controls various genes and its over-expression has been discovered in different kinds of cancers including Hepatocellular Carcinoma (HCC). Extensive research demonstrated that the Wnt signaling is one of the major affected pathways in HCC. This study aimed to find miRNA targeting β-catenin gene by bioinformatic approaches and confirm this correlation to propose new therapeutic targets for HCC. Prediction of miRNAs targeting 3'-Untranslated Regions (UTR) of β-catenin mRNA, were done using different types of credible bioinformatic databases. The luciferase assay was also recruited for further confirmation of the bioinformatic predictions. In the first step, the expression of β-catenin was assessed in the HepG2 cell line by real-time PCR technique. Next, transduction of HepG2 cells were done by lentiviral vectors containing the desired miRNA. Then, the expression level of miRNA and the β-catenin gene were evaluated. Based on the results obtained from different bioinformatic databases, miR-214 was selected as the potential miRNA with the highest probability in targeting β-catenin. Furthermore, Luciferase assay results confirmed the accuracy of our bioinformatic prediction. In line with our hypothesis, after the overexpression of miR-214 in HepG2 cells, β-catenin gene expression was reduced significantly. Gathered results indicate the miRNAs role in the down-regulation of their target genes. Hence, the results propose that miR-214 can prevent HCC development by suppressing β-catenin and may supply a newfound approach towards HCC therapy in humans.

Chinese herbal medicines for prevention and treatment of colorectal cancer: From molecular mechanisms to potential clinical applications

Worldwide, colorectal cancer (CRC) is one of the most common malignant tumors, leading to immense social and economic burdens. Currently, the main treatments for CRC include surgery, chemotherapy, radiotherapy and immunotherapy. Despite advances in the diagnosis and treatment of CRC, the prognosis for CRC patients remains poor. Furthermore, the occurrence of side effects and toxicities severely limits the clinical use of these therapies. Therefore, alternative medications with high efficacy but few side effects are needed. An increasing number of modern pharmacological studies and clinical trials have supported the effectiveness of Chinese herbal medicines (CHMs) for the prevention and treatment of CRC. CHMs may be able to effectively reduce the risk of CRC, alleviate the adverse reactions caused by chemotherapy, and prolong the survival time of patients with advanced CRC. Studies of molecular mechanisms have provided deeper insight into the roles of molecules from CHMs in treating CRC. This paper summarizes the current understanding of the use of CHMs for the prevention and treatment of CRC, the main molecular mechanisms involved in these processes, the role of CHMs in modulating chemotherapy-induced adverse reactions, and CHM's potential role in epigenetic regulation of CRC. The current study provides beneficial information on the use of CHMs for the prevention and treatment of CRC in the clinic, and suggests novel directions for new drug discovery against CRC.

Genetics and signaling mechanisms of orofacial clefts

Craniofacial development involves several complex tissue movements including several fusion processes to form the frontonasal and maxillary structures, including the upper lip and palate. Each of these movements are controlled by many different factors that are tightly regulated by several integral morphogenetic signaling pathways. Subject to both genetic and environmental influences, interruption at nearly any stage can disrupt lip, nasal, or palate fusion and result in a cleft. Here, we discuss many of the genetic risk factors that may contribute to the presentation of orofacial clefts in patients, and several of the key signaling pathways and underlying cellular mechanisms that control lip and palate formation, as identified primarily through investigating equivalent processes in animal models, are examined.

MicroRNA200a enhances antitumor effects in combination with doxorubicin in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is often treated with doxorubicin. MicroRNAs have been shown to have important regulatory roles in cancer and serve as a target in chemoresistance. In this study, we investigated the effects of specific microRNA-200a (miR-200a) on HCC tumor cell growth and effect of doxorubicin-mediated cytotoxicity. Our results show miR-200a is downregulated in human HCC and HCC tumor cell lines. Increasing miR-200a expression inhibited HCC growth and synergized with the antitumor effects of doxorubicin. Inhibiting endogenous miR-200a promoted tumor growth and chemotherapeutic resistance. Increasing miR-200a expression inhibited tumor metabolism (ATP production, mitochondrial respiration, glycolysis), while inhibition of endogenous miR-200a reversed these effects. MiR-200a expression also increased autophagy and synergized with doxorubicin-mediated cytotoxicity. This study identifies a novel role of miR-200a in potentiating doxorubicin-mediated therapeutic effects in HCC.

Relationship between apical junction proteins, gene expression and cancer

The apical junctional complex (AJC) is a cell-cell adhesion system present at the upper portion of the lateral membrane of epithelial cells integrated by the tight junction (TJ) and the adherens junction (AJ). This complex is crucial to initiate and stabilize cell-cell adhesion, to regulate the paracellular transit of ions and molecules and to maintain cell polarity. Moreover, we now consider the AJC as a hub of signal transduction that regulates cell-cell adhesion, gene transcription and cell proliferation and differentiation. The molecular components of the AJC are multiple and diverse and depending on the cellular context some of the proteins in this complex act as tumor suppressors or as promoters of cell transformation, migration and metastasis outgrowth. Here, we describe these new roles played by TJ and AJ proteins and their potential use in cancer diagnostics and as targets for therapeutic intervention.

The c-Myc/AKT1/TBX3 Axis Is Important to Target in the Treatment of Embryonal Rhabdomyosarcoma

Rhabdomyosarcoma is a highly aggressive malignant cancer that arises from skeletal muscle progenitor cells and is the third most common solid tumour in children. Despite significant advances, rhabdomyosarcoma still presents a therapeutic challenge, and while targeted therapy has shown promise, there are limited options because the molecular drivers of rhabdomyosarcoma are poorly understood. We previously reported that the T-box transcription factor 3 (TBX3), which has been identified as a druggable target in many cancers, is overexpressed in rhabdomyosarcoma patient samples and cell lines. To identify new molecular therapeutic targets to treat rhabdomyosarcoma, this study investigates the potential oncogenic role(s) for TBX3 and the factors responsible for upregulating it in this cancer. To this end, rhabdomyosarcoma cell culture models in which TBX3 was either stably knocked down or overexpressed were established and the impact on key hallmarks of cancer were examined using growth curves, soft agar and scratch motility assays, as well as tumour-forming ability in nude mice. Our data show that TBX3 promotes substrate-dependent and -independent proliferation, migration and tumour formation. We further reveal that TBX3 is upregulated by c-Myc transcriptionally and AKT1 post-translationally. This study identifies c-Myc/AKT1/TBX3 as an important axis that could be targeted for the treatment of rhabdomyosarcoma.

Direct and Indirect Suppression of Scn5a Gene Expression Mediates Cardiac Na+ Channel Inhibition by Wnt Signalling

BACKGROUND

Myocardial infarction and heart failure are associated with reduced voltage-gated Na⁺ current (I_Na) that promotes arrhythmias and sudden deaths. We have previously shown that the Wnt/β-catenin signalling (Wnt signalling), which is active in heart disease, reduces cardiac I_Na, suggesting that Wnt signalling may be a potential therapeutic target. However, because Wnt signalling is required for the homeostasis of many noncardiac tissues, administration of Wnt inhibitors to heart patients would cause significant side effects. The present study aims to elucidate the molecular mechanisms of cardiac I_Na inhibition by Wnt, which would identify cardiac-specific therapeutic targets.

METHODS

Wnt signalling was activated in neonatal rat ventricular myocytes by Wnt3a protein. Adenovirus expressing Wnt3a was injected into the adult rat ventricle. CRISPR/Cas9 and chromatin immunoprecipitation were used for mechanistic studies.

RESULTS

Wnt signalling activation in neonatal rat ventricular myocytes reduced Na_v1.5 protein and Scn5a mRNA, but increased Tbx3, a known suppressor of Scn5a. Chromatin immunoprecipitation showed that Wnt signalling inhibits Scn5a expression through downstream mediator (TCF4) binding to both Tbx3 and Scn5a promoters. Overexpression or knockdown of Tbx3 directly modified Na_v1.5 and I_Na, whereas CRISPR/Cas9-induced mutations at TCF4 binding sites within the Scn5a promoter attenuated Wnt inhibition of Scn5a and Na_v1.5. In adult rat hearts, adenovirus expressing Wnt3a reduced Na_v1.5, increased QRS duration in electrocardiogram, and increased the susceptibility to ventricular tachycardia.

CONCLUSIONS

Wnt signalling inhibits the Na⁺ channel by direct and indirect (via Tbx3) suppression of Scn5a transcription. Strategies to block TCF4 binding to the Tbx3 and Scn5a promoters would represent novel strategies for cardiac-specific inhibition of the Wnt pathway to rescue I_Na and prevent sudden cardiac deaths.

The roles and regulation of TBX3 in development and disease

TBX3, a member of the ancient and evolutionary conserved T-box transcription factor family, is a critical developmental regulator of several structures including the heart, mammary glands, limbs and lungs. Indeed, mutations in the human TBX3 lead to ulnar mammary syndrome which is characterized by several clinical malformations including hypoplasia of the mammary and apocrine glands, defects of the upper limb, areola, dental structures, heart and genitalia. In contrast, TBX3 has no known function in adult tissues but is frequently overexpressed in a wide range of epithelial and mesenchymal derived cancers. This overexpression greatly impacts several hallmarks of cancer including bypass of senescence, apoptosis and anoikis, promotion of proliferation, tumour formation, angiogenesis, invasion and metastatic capabilities as well as cancer stem cell expansion. The debilitating consequences of having too little or too much TBX3 suggest that its expression levels need to be tightly regulated. While we have a reasonable understanding of the mutations that result in low levels of functional TBX3 during development, very little is known about the factors responsible for the overexpression of TBX3 in cancer. Furthermore, given the plethora of oncogenic processes that TBX3 impacts, it must be regulating several target genes but to date only a few have been identified and characterised. Interestingly, while there is compelling evidence to support oncogenic roles for TBX3, a few studies have indicated that it may also have tumour suppressor functions in certain contexts. Together, the diverse functional elasticity of TBX3 in development and cancer is thought to involve, in part, the protein partners that it interacts with and this area of research has recently received some attention. This review provides an insight into the significance of TBX3 in development and cancer and identifies research gaps that need to be explored to shed more light on this transcription factor.

TBX3 knockdown suppresses the proliferation of hypopharyngeal carcinoma FaDu cells by inducing G1/S cell cycle arrest and apoptosis

The T-box transcription factor family member TBX3 has been demonstrated to participate in the development of various types of cancer, including head and neck squamous cell carcinoma. However, little is currently known about its role in hypopharyngeal carcinoma. In the present study, the involvement of TBX3 in hypopharyngeal carcinoma was investigated. Immunohistochemical assays revealed that TBX3 levels were increased in hypopharyngeal carcinoma compared with normal tissue samples, accompanied by upregulated N-cadherin and downregulated E-cadherin. Lentivirus-mediated TBX3 knockdown efficiently suppressed its expression and inhibited the proliferation of FaDu cells. The opposite was observed in TBX3-overexpressing FaDu cells. These results indicate that TBX3 is essential for FaDu cell proliferation. Furthermore, TBX3 silencing led to a disturbance of the cell cycle, leading to a decrease in the G₁ phase and an increase in the S phase. In addition, apoptosis was enhanced following TBX3 knockdown. The present results suggest TBX3 as a potential therapeutic target in hypopharyngeal carcinoma.

TBX3 deficiency accelerates apoptosis in cardiomyoblasts through regulation of P21 expression

Congenital heart disease (CHD) is the most common birth defect in newborns. There is increasing evidence that apoptosis and remodeling of the cardiomyoblasts are the major pathology of CHD. Previous research found that T-box transcription factor 3 (TBX3) was compulsory for the regulation of proliferation, cell cycle arrest and apoptosis in various cells. Hence, TBX3 might be involved in the treatment of CHD. The primary aim of this study was to study the effects of TBX3 on apoptosis in aged cardiomyoblasts and investigate the latent mechanism. In the present study, we found TBX3 knockdown induced proliferation inhibition, cell cycle arrest and apoptosis accompanied by mitochondrial dysfunction in cardiomyoblasts at passage 10 to 15. Apoptosis-inducing effects of TBX3 silence could be neutralized by silencing P21 using specific siRNA. In addition, the mRNA and protein expression levels of TBX3 in the heart tissues of sporadic type CHD donors were obviously down-regulated. In conclusion, we demonstrated that TBX3 deficiency accelerated apoptosis via directly regulating P21 expression in senescent cardiomyoblasts.

Transcriptomic Dissection of Hepatocyte Heterogeneity: Linking Ploidy, Zonation, and Stem/Progenitor Cell Characteristics

BACKGROUND & AIMS

There is a long-standing debate regarding the biological significance of polyploidy in hepatocytes. Recent studies have provided increasing evidence that hepatocytes with different ploidy statuses behave differently in a context-dependent manner (eg, susceptibility to oncogenesis, regenerative ability after injury, and in vitro proliferative capacity). However, their overall transcriptomic differences in a physiological context is not known.

METHODS

By using microarray transcriptome analysis, we investigated the heterogeneity of hepatocyte populations with different ploidy statuses. Moreover, by using single-cell quantitative reverse-transcription polymerase chain reaction (scPCR) analysis, we investigated the intrapopulational transcriptome heterogeneity of 2c and 4c hepatocytes.

RESULTS

Microarray analysis showed that cell cycle-related genes were enriched in 8c hepatocytes, which is in line with the established notion that polyploidy is formed via cell division failure. Surprisingly, in contrast to the general consensus that 2c hepatocytes reside in the periportal region, in our bulk transcriptome and scPCR analyses, the 2c hepatocytes consistently showed pericentral hepatocyte-enriched characteristics. In addition, scPCR analysis identified a subpopulation within the 2c hepatocytes that co-express the liver progenitor cell markers Axin2, Prom1, and Lgr5, implying the potential biological relevance of this subpopulation.

CONCLUSIONS

This study provides new insights into hepatocyte heterogeneity, namely 2c hepatocytes are preferentially localized to the pericentral region, and a subpopulation of 2c hepatocytes show liver progenitor cell-like features in terms of liver progenitor cell marker expression (Axin2, Prom1, and Lgr5).

The oncoprotein TBX3 is controlling severity in experimental arthritis

BACKGROUND

Development of autoimmune diseases is the result of a complex interplay between hereditary and environmental factors, with multiple genes contributing to the pathogenesis in human disease and in experimental models for disease. The T-box protein 3 is a transcriptional repressor essential during early embryonic development, in the formation of bone and additional organ systems, and in tumorigenesis.

METHODS

With the aim to find novel genes important for autoimmune inflammation, we have performed genetic studies of collagen-induced arthritis (CIA), a mouse experimental model for rheumatoid arthritis.

RESULTS

We showed that a small genetic fragment on mouse chromosome 5, including Tbx3 and three additional protein-coding genes, is linked to severe arthritis and high titers of anti-collagen antibodies. Gene expression studies have revealed differential expression of Tbx3 in B cells, where low expression was accompanied by a higher B cell response upon B cell receptor stimulation in vitro. Furthermore, we showed that serum TBX3 levels rise concomitantly with increasing severity of CIA.

CONCLUSIONS

From these results, we suggest that TBX3 is a novel factor important for the regulation of gene transcription in the immune system and that genetic polymorphisms, resulting in lower expression of Tbx3, are contributing to a more severe form of CIA and high titers of autoantibodies. We also propose TBX3 as a putative diagnostic biomarker for rheumatoid arthritis.

Expression of TBX3 in Hepatocellular Carcinoma and Its Clinical Implication

Background

Hepatocellular carcinoma (HCC) is the fifth most common malignancy in China, and China’s annual number of new cases accounts for about 45% of the world total. This research was aimed to study the expression of TBX3 protein in HCC and exploring its clinical significance.

Material/Methods

We collected tumor tissues and adjacent non-tumoral tissues of 174 patients with HCC undergoing surgical resection. The expression of TBX3 protein in different tissues and cell lines in vitro (LO2, HHL-5, MHC97-L, MHC97-H) was detected by immunohistochemistry or Western blotting, and the relationship between TBX3 expression and clinical data of patients with HCC was analyzed.

Results

The expression of TBX3 protein in HCC was significantly correlated with histological grade, tumor size, cancer cell metastasis, hepatitis B surface antigen, and the expression of Ki-67 in tumor tissues (P<0.05), and it was positively correlated with serum AFP level (r=0.766, P<0.05). The expression of TBX3 increased with increased histological grade in HCC (P<0.05). Cox regression analysis showed that the expression of TBX3 protein in HCC was an independent risk factor for prognosis (OR=0.524, 95% CI=0.283–0.964). The 5-year survival rate of patients with HCC that highly expressed TBX3 protein was 20.83%, which was significantly lower than the 40.20% rate in patients with low expression (P<0.05).

Conclusions

The expression of TBX3 in HCC patients undergoing surgical resection is high, and its expression increases with the degree of tumor differentiation. It is related to the metastasis of tumor cells and is positively correlated with the serum level of AFP and may affect the survival time of HCC patients undergoing surgical resection.

The special stemness functions of Tbx3 in stem cells and cancer development

The T-box factors belong to an ancient protein family, which comprises a cluster of evolutionarily-conserved transcription factors that regulate gene expression and that are crucial to embryonic development. T-box transcription factor 3 (Tbx3) is a member of this family, is expressed in some tissues, and is a key regulator in many critical organs, including the heart, mammary gland, and limbs. Overexpression of Tbx3 is associated with a number of cancers, including head and neck squamous cell carcinoma, gastric, breast, ovary, cervical, pancreatic, bladder and liver cancers, as well as melanoma. Tbx3 promotes tumor development by modulating cell proliferation, tumor formation, metastasis, cell survival and drug resistance. Moreover, there is strong evidence that Tbx3 regulates stem cell maintenance by controlling stem cell self-renewal and differentiation. Verification of the upstream regulatory factors and potential molecular mechanism of Tbx3, being able to explain the function of Tbx3 in carcinogenic effects and stem cell maintenance, will make a valuable contribution to stem cell and cancer research. This review provides an insight into the current research on Tbx3 and explores the significance of Tbx3 in stem cells and tumorigenesis.

Novel HDAC5-interacting motifs of Tbx3 are essential for the suppression of E-cadherin expression and for the promotion of metastasis in hepatocellular carcinoma

Tbx3, a transcriptional repressor, is essential in the organogenesis of vertebrates, stem cell self-renewal and differentiation, and the carcinogenesis of multiple tumor types. However, the mechanism by which Tbx3 participates in the metastasis of hepatocellular carcinoma (HCC) remains largely unknown. In this study, we show that Tbx3 was dramatically upregulated in clinical HCC samples and that elevated expression of Tbx3 promoted cancer progression. To determine the underlying mechanism, systematic glycine scan mutagenesis and deletion assays were performed. We identified two critical motifs, ⁵⁸⁵LFSYPYT⁵⁹¹ and ⁶⁰⁴HRH⁶⁰⁶, that contribute to the repression of transcriptional activity. These motifs are also essential for Tbx3 to promote cell migration and metastasis both in vitro and in vivo via the suppression of E-cadherin expression. More importantly, Tbx3 directly interacts with HDAC5 via these motifs, and an HDAC inhibitor blocks Tbx3-mediated cell migration and the downregulation of E-cadherin in HCC. As Tbx3 is involved in the carcinogenesis of multiple types of human cancers, our findings suggest an important target for anti-cancer drug development.

A regulatory protein that represses gene activity interacts with an enzyme involved in chromosome remodeling to promote the migration and metastasis of liver cancer cells. Ming-Liang He from the City University of Hong Kong and colleagues found that levels of the T-box transcription factor Tbx3 were dramatically increased in tissue biopsies of liver tumors. They injected Tbx3-expressing human liver cancer cells into mice and saw a positive correlation between Tbx3 activity and cancer progression. By mutating and deleting parts of Tbx3, the researchers identified two particular stretches of the protein that bind histone deacetylase 5, an enzyme involved in ensuring DNA coils, are wound tight to suppress gene activity. This interaction is needed for Tbx3’s tumor-promoting function and may be targetable with drugs in order to prevent metastasis in patients with aggressive liver cancer.

Differential regulation of the Wnt/β-catenin pathway by hepatitis C virus recombinants expressing core from various genotypes

Clinical studies have suggested association of some hepatitis C virus (HCV) subtypes or isolates with progression toward hepatocellular carcinoma (HCC). HCV core protein has been reported to interfere with host Wnt/β-catenin pathway, a cell fate-determining pathway, which plays a major role in HCC. Here, we investigated the impact of HCV core genetic variability in the dysregulation of Wnt/β-catenin pathway. We used both transient expression of core proteins from clinical isolates of HCV subtypes 1a (Cambodia), 4a (Romania) and 4f (Cameroon) and infection systems based on a set of engineered intergenotypic recombinant viruses encoding core from these various clinical strains. We found that TCF transcription factor-dependent reporter activity was upregulated by core in a strain-specific manner. We documented core sequence-specific transcriptional upregulation of several β-catenin downstream target genes associated with cell proliferation and malignant transformation, fibrogenesis or fat accumulation. The extent of β-catenin nuclear translocation varied in accordance with β-catenin downstream gene upregulation in infected cells. Pairwise comparisons of subgenotypic core recombinants and mutated core variants unveiled the critical role of core residues 64 and 71 in these dysregulations. In conclusion, this work identified natural core polymorphisms involved in HCV strain-specific activation of Wnt/β-catenin pathway in relevant infection systems.

AXIN deficiency in human and mouse hepatocytes induces hepatocellular carcinoma in the absence of β-catenin activation

BACKGROUND & AIMS

The Wnt/β-catenin pathway is the most frequently deregulated pathway in hepatocellular carcinoma (HCC). Inactivating mutations of the gene encoding AXIN1, a known negative regulator of the Wnt/β-catenin signaling pathway, are observed in about 10% of HCCs. Whole-genome studies usually place HCC with AXIN1 mutations and CTNNB1 mutations in the group of tumors with Wnt/β-catenin activated program. However, it has been shown that HCCs with activating CTNNB1 mutations form a group of HCCs, with a different histology, prognosis and genomic signature to those with inactivating biallelic AXIN1 mutations. We aimed to elucidate the relationship between CTNNB1 mutations, AXIN1 mutations and the activation level of the Wnt/β-catenin program.

METHODS

We evaluated two independent human HCC datasets for the expression of a 23-β-catenin target genes program. We modeled Axin1 loss of function tumorigenesis in two engineered mouse models and performed gene expression profiling.

RESULTS

Based on gene expression, we defined three levels of β-catenin program activation: strong, weak or no activation. While more than 80% CTNNB1-mutated tumors were found in the strong or in the weak activation program, most of the AXIN1-mutated tumors (>70%) were found in the subgroup with no activation. We validated this result by demonstrating that mice with a hepatocyte specific AXIN1 deletion developed HCC in the absence of β-catenin induction. We defined a 329-gene signature common in human and mouse AXIN1 mutated HCC that is highly enriched in Notch and YAP oncogenic signatures.

CONCLUSIONS

AXIN1-mutated HCCs occur independently of the Wnt/β-catenin pathway and involve Notch and YAP pathways. These pathways constitute potentially interesting targets for the treatment of HCC caused by AXIN1 mutations.

LAY SUMMARY

Liver cancer has a poor prognosis. Defining the molecular pathways involved is important for developing new therapeutic approaches. The Wnt/β-catenin pathway is the most frequently deregulated pathway in hepatocellular carcinoma (HCC). Mutations of AXIN1, a member of this pathway, represent about 10% of HCC mutations. Using both human HCC collections and engineered mouse models of liver cancers with AXIN1 mutation or deletion, we defined a common signature of liver tumors mutated for AXIN1 and demonstrate that these tumors occur independently of the activation of the Wnt/β-catenin pathway.

Carcinogenic activity of pentabrominated diphenyl ether mixture (DE-71) in rats and mice

•

Pentabrominated diphenyl ether (PBDE) mixture was a multispecies carcinogen causing liver tumors in male and female rats and mice.

•

Hras or Ctnnb1 mutations characterized the PBDE-induced liver tumors.

•

PBDE-induced liver tumors increased with increasing PBDE exposure.

Pentabrominated diphenyl ether (PBDE) flame retardants have been phased out in Europe and in the United States, but these lipid soluble chemicals persist in the environment and are found human and animal tissues. PBDEs have limited genotoxic activity. However, in a 2-year cancer study of a PBDE mixture (DE-71) (0, 3, 15, or 50 mg/kg (rats); 0, 3, 30, or 100 mg/kg (mice)) there were treatment-related liver tumors in male and female Wistar Han rats [Crl:WI(Han) after in utero/postnatal/adult exposure, and in male and female B6C3F1 mice, after adult exposure. In addition, there was evidence for a treatment-related carcinogenic effect in the thyroid and pituitary gland tumor in male rats, and in the uterus (stromal polyps/stromal sarcomas) in female rats. The treatment-related liver tumors in female rats were unrelated to the AhR genotype status, and occurred in animals with wild, mutant, or heterozygous Ah receptor. The liver tumors in rats and mice had treatment-related Hras and Ctnnb mutations, respectively. The PBDE carcinogenic activity could be related to oxidative damage, disruption of hormone homeostasis, and molecular and epigenetic changes in target tissue. Further work is needed to compare the PBDE toxic effects in rodents and humans.

SIRT-1 regulates TGF-β-induced dermal fibroblast migration via modulation of Cyr61 expression

SIRT1 is a NAD-dependent protein deacetylase that participates in cellular regulation. The increased migration of fibroblasts is an important phenotype in fibroblast activation. The role of SIRT1 in cell migration remains controversial as to whether SIRT1 acts as an activator or suppressor of cell migration. Therefore, we have established the role of SIRT1 in the migration of human dermal fibroblasts and explored targets of SIRT1 during dermal fibroblast migration. SIRT1 and Cyr61 were expressed in human dermal fibroblasts and the stimulation with TGF-β further induced their expression. Treatment with resveratrol (RSV), a SIRT1 agonist, or overexpression of SIRT1 also promoted the expression Cyr61 in human dermal fibroblasts, whereas the inhibition of SIRT1 activity by nicotinamide or knockdown of SIRT1 decreased the level of Cyr61, as well as TGF-β or RSV-induced Cyr61 expression. Blocking of ERK signaling by PD98509 reduced the expression of Cyr61 induced by TGF-β or RSV. TGF-β, RSV, or SIRT1 overexpression enhanced β-catenin as well as Cyr61 expression. This stimulation was reduced by the Wnt inhibitor XAV939. RSV increased migration and nicotinamide attenuated RSV-induced migration of human dermal fibroblasts. Furthermore, SIRT1 overexpression promoted cell migration, whereas blocking Cyr61 attenuated SIRT1-stimulated migration of human dermal fibroblasts. SIRT1 increased cell migration by stimulating Cyr61 expression and the ERK and Wnt/β-catenin signaling. SIRT1-induced Cyr61 activity is very important for human dermal fibroblasts migration.

Expression level of TBX3 gene in renal carcinoma and its clinical significance

The aim of the current study was to investigate and discuss the function of T-box 3 (TBX3) gene expression in the pathogenesis of renal carcinoma. The carcinoma, adjacent and normal renal tissues of 210 patients with renal carcinoma who presented to The Central Hospital of Wuhan, Tongji Medical College from March, 2006 to March, 2012 were collected to extract total RNAs. The total RNAs were reverse-transcribed into complementary DNA (cDNA), and quantitative polymerase chain reaction (qPCR) was applied to detect the expression of TBX3 gene in these tissues, followed by its association with the prognosis of renal carcinoma as well as clinical features. A comparison of the renal carcinoma tissues with the adjacent tissues showed that TBX3 gene was obviously highly expressed in renal carcinoma tissues (P<0.05). In addition, compared with normal renal tissues, TBX3 gene was obviously highly expressed in renal carcinoma tissues (P<0.05). There was no significant difference in the expression levels of TBX3 gene in normal renal tissues and adjacent tissues (P=0.15). The expression of TBX3 gene in renal carcinoma tissues was not associated with patient age, sex and tumor size (P>0.05), but it was associated with tumor-node-metastasis (TNM) staging and lymph node metastasis (P<0.05). The Kaplan-Meier survival analysis revealed that the median survival time of patients in the positive TBX3 gene expression group (37.5 months) was shorter than that in the negative TBX3 gene expression group (66 months), and there was a statistical difference (P<0.05). The 3- and 5-year survival rates in the negative TBX3 gene expression group were 74 and 62%, respectively, and the 3- and 5-year survival rates in the positive TBX3 gene expression group were 52 and 32%, respectively, and the differences were significant (P<0.05). The results suggest that TBX3 gene is highly expressed in renal carcinoma tissues, and it is associated with TNM staging, lymph node metastasis and distant metastasis, which may be involved in the occurrence and metastasis of renal carcinoma.

Mixed ductal-lobular carcinomas: evidence for progression from ductal to lobular morphology

Mixed ductal–lobular carcinomas (MDLs) show both ductal and lobular morphology, and constitute an archetypal example of intratumoural morphological heterogeneity. The mechanisms underlying the coexistence of these different morphological entities are poorly understood, although theories include that these components either represent ‘collision’ of independent tumours or evolve from a common ancestor. We performed comprehensive clinicopathological analysis of a cohort of 82 MDLs, and found that: (1) MDLs more frequently coexist with ductal carcinoma in situ (DCIS) than with lobular carcinoma in situ (LCIS); (2) the E‐cadherin–catenin complex was normal in the ductal component in 77.6% of tumours; and (3) in the lobular component, E‐cadherin was almost always aberrantly located in the cytoplasm, in contrast to invasive lobular carcinoma (ILC), where E‐cadherin is typically absent. Comparative genomic hybridization and multiregion whole exome sequencing of four representative cases revealed that all morphologically distinct components within an individual case were clonally related. The mutations identified varied between cases; those associated with a common clonal ancestry included BRCA2, TBX3, and TP53, whereas those associated with clonal divergence included CDH1 and ESR1. Together, these data support a model in which separate morphological components of MDLs arise from a common ancestor, and lobular morphology can arise via a ductal pathway of tumour progression. In MDLs that present with LCIS and DCIS, the clonal divergence probably occurs early, and is frequently associated with complete loss of E‐cadherin expression, as in ILC, whereas, in the majority of MDLs, which present with DCIS but not LCIS, direct clonal divergence from the ductal to the lobular phenotype occurs late in tumour evolution, and is associated with aberrant expression of E‐cadherin. The mechanisms driving the phenotypic change may involve E‐cadherin–catenin complex deregulation, but are yet to be fully elucidated, as there is significant intertumoural heterogeneity, and each case may have a unique molecular mechanism. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

T-box Transcription Factor Tbx3 Contributes to Human Hepatocellular Carcinoma Cell Migration and Invasion by Repressing E-Cadherin Expression

Tbx3, a member of the T-box family of transcription factors, contributes directly to tumor formation, migration, and invasion. However, the role of Tbx3 in the metastasis of HCC remains unclear. In the present study, Tbx3 expression was detected in HCC tissues and cells by Western blot, and Tbx3 expression was regulated by use of siRNAs or lentivirus-mediated vectors. Here we found that Tbx3 protein expression increased in HCC tissues and cell lines. Tbx3 expression was positively associated with multiple tumor nodes, venous infiltration, and advanced TNM tumor stage. Survival analysis demonstrated that Tbx3 expression was an independent prognostic factor for HCC patients. In vitro assays further validated that Tbx3 indeed prompted HCC cell migration and invasion. In addition, Tbx3 expression was negatively related with E-cadherin expression in HCC tissues. Mechanically, Tbx3 inhibited the expression of E-cadherin, and then facilitated epithelial-mesenchymal transition (EMT) of HCC cells. Furthermore, the effect of Tbx3 knockdown on HCC cells was attenuated by E-cadherin knockdown. In conclusion, Tbx3 may be a novel prognostic factor, and it contributes to HCC cell migration, invasion, and EMT by repressing E-cadherin expression. Thus, Tbx3 may be recommended as a therapeutic target for HCC patients.

E-Cadherin/β-Catenin Complex: A Target for Anticancer and Antimetastasis Plants/Plant-derived Compounds

Plants reputed to have cancer-inhibiting potential and putative active components derived from those plants have emerged as an exciting new field in cancer study. Some of these compounds have cancer-inhibiting potential in different clinical staging levels, especially metastasis. A few of them which stabilize cell-cell adhesions are controversial topics. This review article introduces some effective herbal compounds that target E-cadherin/β-catenin protein complex. In this article, at first, we briefly review the structure and function of E-cadherin and β-catenin proteins, Wnt signaling pathway, and its target genes. Then, effective compounds of the Teucrium persicum, Teucrium polium, Allium sativum (garlic), Glycine max (soy), and Brassica oleracea (broccoli) plants, which influence stability and cellular localization of E-cadherin/β-catenin complex, were studied. Based on literature review, there are some compounds in these plants, including genistein of soy, sulforaphane of broccoli, organosulfur compounds of garlic, and the total extract of Teucrium genus that change the expression of variety of Wnt target genes such as MMPs, E-cadherin, p21, p53, c-myc, and cyclin D1. So they may induce cell-cycle arrest, apoptosis and/or inhibition of Epithelial-Mesenchymal Transition (EMT) and metastasis.

DNA Methylation Changes in Tbx3 in a Mouse Model Exposed to Polybrominated Diphenyl Ethers

DE-71, a commercial mixture of polybrominated diphenyl ethers widely used in flame retardants, is a pervasive environmental contaminant due to its continuing release from waste material and its long half-life in humans. Although the genotoxic potential of DE-71 appears to be low based on bacterial mutagenicity, it remains a public health concern due to its reported involvement in tumor development. Molecular mechanisms by which DE-71 influences tumor incidence or progression remain understudied. We used liver carcinoma tissue from mice exposed to DE-71 to test the hypothesis that epigenetic alterations consistent with tumor development, specifically DNA methylation, result from long-term DE-71 exposure. We profiled DNA methylation status using the methylated-CpG island recovery assay coupled with microarray analysis of hepatocellular carcinoma DNA from animals exposed to DE-71. DE-71 exposure had little impact on global DNA methylation. However, we detected gene body-specific hypomethylation within the Tbx3 locus, a transcription factor important in liver tumorigenesis and in embryonic and cancer stem cell proliferation. This nonpromoter hypomethylation was accompanied by upregulation of Tbx3 mRNA and protein and by alterations in downstream cell cycle-associated marker expression. Thus, exposure to DE-71 may facilitate tumor development by inducing epigenetic programs that favor expansion of progenitor cell populations.

Healing efficacy of fracture-targeted GSK3β inhibitor-loaded micelles for improved fracture repair

Aim: To evaluate the fracture healing capabilities of a GSK3β inhibitor, 6-bromoindirubin-3′-oxime, coupled with an aspartic acid octapeptide in a micellar delivery system. Materials & methods: The efficacy of the intravenously administered micelles to accelerate healing of femoral fracture in mice was evaluated. Micro-computed tomography analysis was employed to obtain bone density, total volume, relative volume, trabecular thickness and trabecular spacing.Results: Both fracture bone mineral density and volume were significantly higher in the micelle treatment groups when compared with controls. The fracture-targeted micelle demonstrates fracture-specific bone anabolism and biocompatibility in off-target tissues. Conclusion: Accelerated fracture healing in mice was achieved by targeting the GSK3β inhibitor, 6-bromoindirubin-3′-oxime, to the fracture site.

The role of T-box genes in the tumorigenesis and progression of cancer

The T-box (TBX) genes are part of an evolutionarily conserved family of transcription factors involved in organ development. They serve key roles in a number of molecular mechanisms, including proliferation, cell fate and organ identity. In addition, previous studies suggest that TBX genes have essential functions in the tumorigenesis and progression of various types of cancer. For example, TBX proteins served significant roles in carcinogenesis, proliferation and differentiation, senescence and apoptosis, invasion and migration, mesenchymal-epithelial and epithelial-mesenchymal transition, oncogenic signaling pathways and drug sensitivity. However, the exact mechanisms by which TBX genes carry out these functions have not yet been fully elucidated. The present review focuses on the role of TBX genes in cancer, with the aim of further clarifying their function. As altered levels of TBX proteins have detrimental consequences in numerous types of cancer, there is a need for further research into TBX genes, which this review may aid through providing a comprehensive insight into the topic.

Tbx3 overexpression in human gastric cancer is correlated with advanced tumor stage and nodal status and promotes cancer cell growth and invasion

The objective of the current study was to investigate the expression pattern of Tbx3 and its clinicopathological significance in patients with gastric cancer. The expression pattern of Tbx3 in gastric cancer tissues and adjacent noncancerous surface epithelia and mucosal glands was detected by immunohistochemistry. Tbx3 was found to be overexpressed in 46 of 98 human gastric cancer samples, and this correlated with advanced clinical stage, tumor stage, and nodal status. In addition, in the SGC-7901 gastric cancer cell line, Tbx3 overexpression by plasmid transfection promoted growth and invasion. Conversely, depleting Tbx3 expression by small-interfering RNA inhibited proliferation and invasion in BGC-823 cell line. Moreover, Tbx3 accelerated cell cycle progression at the G1/S boundary. Tbx3 also regulated epithelial-to-mesenchymal transition (EMT) to promote cell invasion by repressing E-cadherin expression and increasing expression levels N-cadherin, vimentin. These results indicate that in gastric cancer, Tbx3 plays an important role and might be a useful therapy target.