Dysregulation of lncRNA TFAP2A-AS1 is involved in the pathogenesis of pulpitis by the regulation of microRNA-32-5p.

OBJECTIVE: This study was designed to evaluate TFAP2A-AS1 expression in the dental pulp of teeth with or without pulpitis and to determine the function of TFAP2A-AS1 in pulp cells. METHODS: GSE92681 was analyzed to filter out differentially expressed lncRNAs. Pulp samples from teeth with pulpitis and healthy teeth (control) were examined using real-time (RT) quantitative polymerase chain reaction (qPCR). Human dental pulp stem cells (hDPSCs) were cultured in a specific medium for osteogenic induction, or treated with lipopolysaccharide (LPS) to simulate inflammation. The viability and apoptosis of human DPSCs (hDPSCs) were determined by XTT assay and apoptosis detection kit. Inflammation was induced by LPS and assessed by measuring the expression and release of inflammatory cytokines after TFAP2A-AS1 knockdown. Osteogenic differentiation of hDPSCs was investigated by determining expression levels of osteogenic markers and alkaline phosphatase (ALP) activity after TFAP2A-AS1 overexpression. The downstream microRNA (miRNA) was predicted. Dual-luciferase reporter was used to confirm the binding between miR-32-5p and TFAP2A-AS1. RESULTS: The expression of TFAP2A-AS1 was evaluated in inflamed pulp using RT-qPCR. TFAP2A-AS1 had a discriminatory ability for healthy individuals and patients with pulpitis. The expression of TFAP2A-AS1 decreased upon the osteogenic differentiation of hDPSCs, and increased upon the LPS induction. TFAP2A-AS1 can reverse the osteogenic differentiation of hDPSCs, as evidenced by decreased levels of dentine sialophosphoprotein, dentin matrix protein-1, and ALP activity. TFAP2A-AS1 knockdown can promote cell proliferation of hDPSCs and relieve LPS-induced inflammation, as evidenced by decreased levels of TNF-α, IL-1ß, and IL-6. miR-32-5p was identified as a downstream miRNA of TFAP2A-AS1. CONCLUSION: This study demonstrated the expression and potential function of TFAP2A-AS1 in the human dental pulp. TFAP2A-AS1 can inhibit odontogenic differentiation but promote inflammation in pulp cells.

Single-cell transcriptomics reveals the cellular identity of a novel progenitor population crucial for murine neural tube closure.

Neural tube closure in vertebrates is achieved through a highly dynamic and coordinated series of morphogenic events involving neuroepithelium, surface ectoderm, and neural plate border. Failure of this process in the caudal region causes spina bifida. Grainyhead-like 3 (GRHL3) is an indispensable transcription factor for neural tube closure as constitutive inactivation of the Grhl3 gene in mice leads to fully penetrant spina bifida. Here, through single-cell transcriptomics we show that at E8.5, the time-point preceding mouse neural tube closure, co-expression of Grhl3, Tfap2a, and Tfap2c defines a previously unrecognised progenitor population of surface ectoderm integral for neural tube closure. Deletion of Grhl3 expression in this cell population using a Tfap2a-Cre transgene recapitulates the spina bifida observed in Grhl3-null animals. Moreover, conditional inactivation of Tfap2c expression in Grhl3-expressing neural plate border cells also induces spina bifida. These findings indicate that a specific neural plate border cellular cohort is required for the early-stage neurulation.

AP-2α gene deregulation is associated with renal cell carcinoma patient survival.

BACKGROUND: Renal cell carcinoma (RCC), one of the most fatal urologic tumors, accounts for approximately 3% of all adult cancers and exhibits a high metastatic index at diagnosis and a high rate of relapse. Radical or partial nephrectomy is a curative option for nonmetastatic RCCs. Targeted therapy has been shown to improve the survival of patients with metastatic RCCs. However, the underlying cellular and molecular events associated with RCC pathogenesis are not well known. METHODS: To investigate the clinical role of the transcription factor activator protein (AP)-2α in RCC, methylated CpG island recovery assays and microarray analysis were employed. COBRA and RT‒qPCR assays were performed to assess AP-2α expression in RCC. RESULTS: A negative correlation was noted between AP-2α mRNA expression levels and methylation status. Multivariate analyses showed that AP-2α mRNA was a major risk factor not only for overall and disease-free survival in RCC but also for disease-free survival in clear cell RCC. CONCLUSIONS: Our results indicated that AP-2α expression was deregulated in RCC and associated with overall patient survival and disease-free survival. Such findings suggest that AP-2α might play an important role in the pathogenesis of RCC.

TFAP2A Activates S100A2 to Mediate Glutamine Metabolism and Promote Lung Adenocarcinoma Metastasis.

BACKGROUND: Lung adenocarcinoma (LUAD) is a fatal disease with metabolic abnormalities. The dysregulation of S100 calcium-binding protein A2 (S100A2), a member of the S100 protein family, is connected to the development of various cancers. The impact of S100A2 on the LUAD occurrence and metastasis, however, has not yet been reported. The functional mechanism of S100A2 on LUAD cell metastasis was examined in this article. METHODS: The expression of TFAP2A and S100A2 in LUAD tissues and cells was analyzed by bioinformatics and qRT-PCR, respectively. The enrichment pathway analysis was performed on S100A2. Bioinformatics analysis determined the binding relationship between TFAP2A and S100A2, and their interaction was validated through dual-luciferase and chromatin immunoprecipitation experiments. Cell viability was determined using cell counting kit-8 (CCK-8). A transwell assay was performed to analyze the invasion and migration of cells. Immunofluorescence was conducted to obtain vimentin and E-cadherin expression, and a western blot was used to detect the expression of MMP-2, MMP-9, GLS, and GLUD1. The kits measured the NADPH/NADP ratio, glutathione (GSH)/glutathione disulfide (GSSG) levels, and the contents of glutamine, α-KG, and glutamate. RESULTS: S100A2 was upregulated in LUAD tissues and cells, and S100A2 mediated glutamine metabolism to induce LUAD metastasis. Additionally, the transcriptional regulator TFAP2A was discovered upstream of S100A2, and TFAP2A expression was upregulated in LUAD, which indicated that TFAP2A promoted the S100A2 expression. The rescue experiment found that upregulation of S100A2 could reverse the inhibitory effects of silencing TFAP2A on glutamine metabolism and cell metastasis. CONCLUSION: In conclusion, by regulating glutamine metabolism, the TFAP2A/S100A2 axis facilitated LUAD metastasis. This suggested that targeting S100A2 could be beneficial for LUAD treatment.

TFAP2A is involved in neuropathic pain by regulating Grin1 expression in glial cells of the dorsal root ganglion.

Neuropathic pain is a highly prevalent and refractory condition, yet its mechanism remains poorly understood. While NR1, the essential subunit of NMDA receptors, has long been recognized for its pivotal role in nociceptive transmission, its involvement in presynaptic stimulation is incompletely elucidated. Transcription factors can regulate the expression of both pro-nociceptive and analgesic factors. Our study shows that transcription factor TFAP2A was up-regulated in the dorsal root ganglion (DRG) neurons, satellite glial cells (SGCs), and Schwann cells following spinal nerve ligation (SNL). Intrathecal injection of siRNA targeting Tfap2a immediately or 7 days after SNL effectively alleviated SNL-induced pain hypersensitivity and reduced Tfap2a expression levels. Bioinformatics analysis revealed that TFAP2A may regulate the expression of the Grin1 gene, which encodes NR1. Dual-luciferase reporter assays confirmed TFAP2A's positive regulation of Grin1 expression. Notably, both Tfap2a and Grin1 were expressed in the primary SGCs and upregulated by lipopolysaccharides. The expression of Grin1 was also down-regulated in the DRG following Tfap2a knockdown. Furthermore, intrathecal injection of siRNA targeting Grin1 immediately or 7 days post-SNL effectively alleviated SNL-induced mechanical allodynia and thermal hyperalgesia. Finally, intrathecal Tfap2a siRNA alleviated SNL-induced neuronal hypersensitivity, and incubation of primary SGCs with Tfap2a siRNA decreased NMDA-induced upregulation of proinflammatory cytokines. Collectively, our study reveals the role of TFAP2A-Grin1 in regulating neuropathic pain in peripheral glia, offering a new strategy for the development of novel analgesics.

IGF2BP3 suppresses ferroptosis in lung adenocarcinoma by m6A-dependent regulation of TFAP2A to transcriptionally activate SLC7A11/GPX4.

Ferroptosis is recently discovered as an important player in the initiation, proliferation, and progression of human tumors. Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) has been reported as an oncogene in multiple types of cancers, including lung adenocarcinoma (LUAD). However, little research has been designed to investigate the regulation of IGF2BP3 on ferroptosis in LUAD. qRT-PCR and western blot were used to measure the mRNA and protein expression of IGF2BP3 and transcription factor AP-2 alpha (TFAP2A). CCK-8 assay was performed to determine cell viability. DCFH-DA and C11-BODIPY staining were used to detect the levels of intracellular reactive oxygen species (ROS) and lipid ROS. The corresponding assay kits were used to analyze the levels of malondialdehyde (MDA) and glutathione (GSH). SRAMP website and m6A RNA immunoprecipitation (Me-RIP) were used to predict and confirm the m6A modification of TFAP2A. RIP experiments were conducted to confirm the binding of IGF2BP3 and TFAP2A. RNA stability assay was performed using actinomycin D. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter experiments were performed to confirm the interaction between TFAP2A and cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11) or glutathione peroxidase 4 (GPX4). Mice xenotransplant model was also constructed to explore the effect of IGF2BP3 on LUAD tumor growth and ferroptosis. IGF2BP3 and TFAP2A were both highly expressed in LUAD. IGF2BP3 or TFAP2A knockdown induced ferroptosis by aggravating erastin-induced cell viability suppression, increasing the production of intracellular ROS, lipid ROS, and MDA, and decreasing GSH synthesis, GSH/GSSG ratio, and cystine uptake. Mechanistically, IGF2BP3 stabilized TFAP2A expression via m6A modification. Moreover, sh-IGF2BP3-mediated ferroptosis was significantly abated by TFAP2A overexpression. Furthermore, TFAP2A binds to the promoters of SLC7A11 and GPX4 to promote their transcription. Also, IGF2BP3 depletion suppressed LUAD tumor growth by inducing ferroptosis in mice. IGF2BP3 suppresses ferroptosis in LUAD by m6A-dependent regulation of TFAP2A to promote the transcription of SLC7A11 and GPX4. Our findings suggest that targeting IGF2BP3/TFAP2A/SLC7A11/GPX4 axis might be a potential therapeutic choice to increase ferroptosis sensitivity in LUAD.

TFAP2A downregulation mediates tumor-suppressive effect of miR-8072 in triple-negative breast cancer via inhibiting SNAI1 transcription.

BACKGROUND: Triple-negative breast cancer (TNBC) represents a highly aggressive subset of breast malignancies characterized by its challenging clinical management and unfavorable prognosis. While TFAP2A, a member of the AP-2 transcription factor family, has been implicated in maintaining the basal phenotype of breast cancer, its precise regulatory role in TNBC remains undefined. METHODS: In vitro assessments of TNBC cell growth and migratory potential were conducted using MTS, colony formation, and EdU assays. Quantitative PCR was employed to analyze mRNA expression levels, while Western blot was utilized to evaluate protein expression and phosphorylation status of AKT and ERK. The post-transcriptional regulation of TFAP2A by miR-8072 and the transcriptional activation of SNAI1 by TFAP2A were investigated through luciferase reporter assays. A xenograft mouse model was employed to assess the in vivo growth capacity of TNBC cells. RESULTS: Selective silencing of TFAP2A significantly impeded the proliferation and migration of TNBC cells, with elevated TFAP2A expression observed in breast cancer tissues. Notably, TNBC patients exhibiting heightened TFAP2A levels experienced abbreviated overall survival. Mechanistically, TFAP2A was identified as a transcriptional activator of SNAI1, a crucial regulator of epithelial-mesenchymal transition (EMT) and cellular proliferation, thereby augmenting the oncogenic properties of TFAP2A in TNBC. Moreover, miR-8072 was unveiled as a negative regulator of TFAP2A, exerting potent inhibitory effects on TNBC cell growth and migration. Importantly, the tumor-suppressive actions mediated by the miR-8072/TFAP2A axis were intricately associated with the attenuation of AKT/ERK signaling cascades and the blockade of EMT processes. CONCLUSIONS: Our findings unravel the role and underlying molecular mechanism of TFAP2A in driving tumorigenesis of TNBC. Targeting the TFAP2A/SNAI1 pathway and utilizing miR-8072 as a suppressor represent promising therapeutic strategies for treating TNBC.

The effect of TFAP2A/ANXA8 axis on ferroptosis of cervical squamous cell carcinoma (CESC) in vitro.

Potential role and associated mechanisms of Annexin A8 (ANXA8), a member of the Annexins family, in cervical squamous cell carcinoma (CESC) are still unclear, despite being upregulated in various malignant tumors. Here, we observed a notably elevated expression of ANXA8 in CESC cells. The inhibition of ANXA8 amplified the susceptibility of CESC cells to Erastin and sorafenib-induced ferroptosis, whereas it exerted minimal influence on DPI7 and DPI10-induced ferroptosis. The results from the Fe2+ concentration assay showed no significant correlation between ANXA8 gene knockdown and intracellular Fe2+ concentration induced by ferroptosis inducers. Western blot analysis demonstrated that the knockdown of ANXA8 did not alter ACSL4 and LPCAT levels under ferroptosis-inducing conditions, but it did result in a reduction in intracellular GSH levels induced by the ferroptosis inducer. Subsequently, we identified TFAP2A as an upstream transcription factor of ANXA8, which plays a role in regulating cell ferroptosis. The knockdown of TFAP2A significantly elevated MDA levels and depressed GSH levels in the presence of a ferroptosis inducer, thereby inhibiting cell ferroptosis. However, this inhibitory effect could be reversed by ANXA8 overexpression. Therefore, our research suggests that the TFAP2A/ANXA8 axis exerts regulatory control over ferroptosis in CESC cells by mediating GSH synthesis in System Xc.

miR-137 confers robustness to the territorial restriction of the neural plate border.

The neural plate border (NPB) of vertebrate embryos is segregated from the neural plate (NP) and epidermal regions, and comprises an intermingled group of progenitors with multiple fate potential. Recent studies have shown that, during the gastrula stage, TFAP2A acts as a pioneer factor in remodeling the epigenetic landscape required to activate components of the NPB induction program. Here, we show that chick Tfap2a has two highly conserved binding sites for miR-137, and both display a reciprocal expression pattern at the NPB and NP, respectively. In addition, ectopic miR-137 expression reduced TFAP2A, whereas its functional inhibition expanded their territorial distribution overlapping with PAX7. Furthermore, we demonstrate that loss of the de novo DNA methyltransferase DNMT3A expanded miR-137 expression to the NPB. Bisulfite sequencing revealed a markedly elevated presence of non-canonical CpH methylation within the miR-137 promoter region when comparing NPB and NP samples. Our findings show that miR-137 contributes to the robustness of NPB territorial restriction in vertebrate development.

TFAP2A Upregulates SKA3 to Promote Glycolysis and Reduce the Sensitivity of Lung Adenocarcinoma Cells to Cisplatin.

INTRODUCTION: Studies have shown that glycolysis metabolism affects the resistance or sensitivity of tumors to chemotherapy drugs. Emerging from recent research, a paradigm-shifting revelation has unfolded, elucidating the oncogenic nature of SKA3 within the context of lung adenocarcinoma (LUAD). Consequently, this work was designed to delve into the effects of SKA3 on glycolysis and cisplatin (CDDP) resistance in LUAD cells and to find new possibilities for individualized treatment of LUAD. METHODS: LUAD mRNA expression data from the TCGA database were procured to scrutinize the differential expression patterns of SKA3 in both tumor and normal tissues. GSEA and Pearson correlation analyses were employed to elucidate the impact of SKA3 on signaling pathways within the context of LUAD. In order to discern the upstream regulatory mechanisms, the ChEA and JASPAR databases were utilized to predict the transcription factors and binding sites associated with SKA3. qRT-PCR and Western blot were implemented to assay the mRNA and protein expression levels of SKA3 and TFAP2A. Chromatin immunoprecipitation and dual-luciferase assays were performed to solidify the binding relationship between the two. Extracellular acidification rate, glucose consumption, lactate production, and glycolysis-related proteins (HK2, GLUT1, and LDHA) were used to evaluate the level of glycolysis. Cell viability under CDDP treatment was determined utilizing the CCK-8, allowing for the calculation of IC50. The expression levels of SKA3 and TFAP2A proteins were detected by immunohistochemistry (IHC). RESULTS: SKA3 exhibited upregulation in LUAD tissues and cell lines, establishing a direct linkage with glycolysis pathway. Overexpression of SKA3 fostered glycolysis in LUAD, resulting in reduced sensitivity toward CDDP treatment. The upstream transcription factor of SKA3, TFAP2A, was also upregulated in LUAD and could promote SKA3 transcription. Overexpression of TFAP2A also fostered the glycolysis of LUAD. Rescue assays showed that TFAP2A promoted glycolysis in LUAD cells by activating SKA3, reducing the sensitivity of LUAD cells to CDDP. The IHC analysis revealed a positive correlation between high expression of SKA3 and TFAP2A and CDDP resistance. CONCLUSION: In summary, TFAP2A can transcriptionally activate SKA3, promote glycolysis in LUAD, and protect LUAD cells from CDDP treatment, indicating that targeting the TFAP2A/SKA3 axis may become a plausible and pragmatic therapeutic strategy for the clinical governance of LUAD.

miR-1293 suppresses osteosarcoma progression by modulating drug sensitivity in response to cisplatin treatment.

Chemotherapy is considered the primary treatment for osteosarcoma. however, its effectiveness is limited due to drug resistance and toxicity. Thus, identifying novel therapeutic targets to enhance the efficacy of chemotherapy is urgently needed. Here, we identified a novel cisplatin-sensitivity enhancing mechanism via up-regulation of the tumour suppressor gene, miR-1293. Meanwhile, higher levels of miR-1293 observed in prechemotherapy patients were associated with a more favorable prognosis. The mechanism underlying cisplatin upregulated miR-1293 expression involves hypomethylation of the miR-1293 promoter, which blocks the binding of the transcription repressor TFAP2A to the promoter. Furthermore, miR-1293 inhibits osteosarcoma progression by targeting TIMP1 to inactivate the Notch1/Hes1 and TGFBR1/Smad2/3 pathways, thereby promoting tumour cell death. The findings presented herein unveil a novel mechanism for enhancing cisplatin sensitivity and proposed a potential therapeutic strategy for osteosarcoma through pre-chemotherapy supplementation of miR-1293.

The Aryl Hydrocarbon Receptor Regulates Epidermal Differentiation through Transient Activation of TFAP2A.

The aryl hydrocarbon receptor (AHR) is an evolutionary conserved environmental sensor identified as an indispensable regulator of epithelial homeostasis and barrier organ function. Molecular signaling cascade and target genes upon AHR activation and their contribution to cell and tissue function are however not fully understood. Multiomics analyses using human skin keratinocytes revealed that upon ligand activation, AHR binds open chromatin to induce expression of transcription factors, for example, TFAP2A, as a swift response to environmental stimuli. The terminal differentiation program, including upregulation of barrier genes, FLG and keratins, was mediated by TFAP2A as a secondary response to AHR activation. The role of AHR-TFAP2A axis in controlling keratinocyte terminal differentiation for proper barrier formation was further confirmed using CRISPR/Cas9 in human epidermal equivalents. Overall, the study provides additional insights into the molecular mechanism behind AHR-mediated barrier function and identifies potential targets for the treatment of skin barrier diseases.

Potential prognosis and immunotherapy predictor TFAP2A in pan-cancer.

BACKGROUND: TFAP2A is critical in regulating the expression of various genes, affecting various biological processes and driving tumorigenesis and tumor development. However, the significance of TFAP2A in carcinogenesis processes remains obscure. METHODS: In our study, we explored multiple databases including TCGA, GTEx, HPA, cBioPortal, TCIA, and other well-established databases for further analysis to expound TFAP2A expression, genetic alternations, and their relationship with the prognosis and cellular signaling network alternations. GO term and KEGG pathway enrichment analysis as well as GSEA were conducted to examine the common functions of TFAP2A. RT-qPCR, Western Blot and Dual Luciferase Reporter assay were employed to perform experimental validation. RESULTS: TFAP2A mRNA expression level was upregulated and its genetic alternations were frequently present in most cancer types. The enrichment analysis results prompted us to investigate the changes in the tumor immune microenvironment further. We discovered that the expression of TFAP2A was significantly associated with the expression of immune checkpoint genes, immune subtypes, ESTIMATE scores, tumor-infiltrating immune cells, and the possible role of TFAP2A in predicting immunotherapy efficacy. In addition, high TFAP2A expression significantly correlated with several ICP genes, and promoted the expression of PD-L1 on mRNA and protein levels through regulating its expression at the transcriptional level. TFAP2A protein level was upregulated in fresh colon tumor tissue samples compared to that in the adjacent normal tissues, which essentially positively correlated with the expression of PD-L1. CONCLUSIONS: Our study suggests that targeting TFAP2A may provide a novel and effective strategy for cancer treatment.

TFAP2A activates HMGA1 to promote glycolysis and lung adenocarcinoma progression.

BACKGROUND: Lung cancer is the most common cancer in the world. High Mobility Group AT-Hook 1 (HMGA1) is found to be associated with the glycolytic pathway in a variety of cancers, and abnormal glycolysis function is one of the important characteristics of cancer cells. Therefore, this paper discusses the effect of HMGA1 on glycolysis of lung adenocarcinoma (LUAD) cells METHODS: The mRNA expression data were downloaded from TCGA-LUAD database. Groups were set according to the median expression of HMGA1, followed by GSEA enrichment analysis. The upstream transcriptional regulators of HMGA1 were predicted by bioinformatics. The correlation between HMGA1 and Transcription Factor AP-2 Alpha (TFAP2A) and their expression in LUAD tissues were analyzed as well. mRNA expression levels of HMGA1 and TFAP2A were detected by qRT-PCR. The binding of HMGA1 and TFAP2A was demonstrated by ChIP and dual luciferase reporter assays. Cell function experiments were utilized to assay proliferation, apoptosis, glycolysis ability of LUAD cells, and glycolysis-related protein expression in each treatment group. RESULTS: HMGA1 was highly expressed in LUAD patients' tissues and enriched in the glycolytic pathway. Additionally, silencing HMGA1 markedly hampered cell proliferation and glycolysis, and promoted cell apoptosis. The upstream transcriptional regulator TFAP2A was predicted to be highly expressed in LUAD. ChIP and dual luciferase reporter assays confirmed the targeted relationship between HMGA1 and TFAP2A. Cell rescue assay confirmed that TFAP2A promoted glycolysis and LUAD progression by activating HMGA1. CONCLUSION: TFAP2A promotes glycolysis, proliferation and hampers apoptosis of LUAD cells by stimulating HMGA1. Hence, TFAP2A/HMGA1 may be a feasible therapeutic target for LUAD. AVAILABILITY OF DATA AND MATERIALS: All the data within this manuscript could be gotten from corresponding author at reasonable request.

HNRNPC promotes collagen fiber alignment and immune evasion in breast cancer via activation of the VIRMA-mediated TFAP2A/DDR1 axis.

BACKGROUND: Cancers aggressively reorganize collagen in their microenvironment, leading to the evasion of tumor cells from immune surveillance. However, the biological significance and molecular mechanism of collagen alignment in breast cancer (BC) have not been well established. METHODS: In this study, BC-related RNA-Seq data were obtained from the TCGA database to analyze the correlation between DDR1 and immune cells. Mouse BC cells EO771 were selected for in vitro validation, and dual-luciferase experiments were conducted to examine the effect of TFAP2A on DDR1 promoter transcription activity. ChIP experiments were performed to assess TFAP2A enrichment on the DDR1 promoter, while Me-RIP experiments were conducted to detect TFAP2A mRNA m6A modification levels, and PAR-CLIP experiments were conducted to determine VIRMA's binding to TFAP2A mRNA and RIP experiments to investigate HNRNPC's recognition of m6A modification on TFAP2A mRNA. Additionally, an in vivo mouse BC transplant model and the micro-physiological system was constructed for validation, and Masson staining was used to assess collagen fiber arrangement. Immunohistochemistry was conducted to identify the number of CD8-positive cells in mouse BC tumors and Collagen IV content in ECM, while CD8 + T cell migration experiments were performed to measure CD8 + T cell migration. RESULTS: Bioinformatics analysis showed that DDR1 was highly expressed in BC and negatively correlated with the proportion of anti-tumor immune cell infiltration. In vitro cell experiments indicated that VIRMA, HNRNPC, TFAP2A, and DDR1 were highly expressed in BC cells. In addition, HNRNPC promoted TFAP2A expression and, therefore, DDR1 transcription by recognizing the m6A modification of TFAP2A mRNA by VIRMA. In vivo animal experiments further confirmed that VIRMA and HNRNPC enhanced the TFAP2A/DDR1 axis, promoting collagen fiber alignment, reducing anti-tumor immune cell infiltration, and promoting immune escape in BC. CONCLUSION: This study demonstrated that HNRNPC promoted DDR1 transcription by recognizing VIRMA-unveiled m6A modification of TFAP2A mRNA, which enhanced collagen fiber alignment and ultimately resulted in the reduction of anti-tumor immune cell infiltration and promotion of immune escape in BC.

The aryl hydrocarbon receptor regulates epidermal differentiation through transient activation of TFAP2A.

The aryl hydrocarbon receptor (AHR) is an evolutionary conserved environmental sensor identified as indispensable regulator of epithelial homeostasis and barrier organ function. Molecular signaling cascade and target genes upon AHR activation and their contribution to cell and tissue function are however not fully understood. Multi-omics analyses using human skin keratinocytes revealed that, upon ligand activation, AHR binds open chromatin to induce expression of transcription factors (TFs), e.g., Transcription Factor AP-2α (TFAP2A), as a swift response to environmental stimuli. The terminal differentiation program including upregulation of barrier genes, filaggrin and keratins, was mediated by TFAP2A as a secondary response to AHR activation. The role of AHR-TFAP2A axis in controlling keratinocyte terminal differentiation for proper barrier formation was further confirmed using CRISPR/Cas9 in human epidermal equivalents. Overall, the study provides novel insights into the molecular mechanism behind AHR-mediated barrier function and potential novel targets for the treatment of skin barrier diseases.

Principles of Zebrafish Nephron Segment Development.

Nephrons are the functional units which comprise the kidney. Each nephron contains a number of physiologically unique populations of specialized epithelial cells that are organized into discrete domains known as segments. The principles of nephron segment development have been the subject of many studies in recent years. Understanding the mechanisms of nephrogenesis has enormous potential to expand our knowledge about the basis of congenital anomalies of the kidney and urinary tract (CAKUT), and to contribute to ongoing regenerative medicine efforts aimed at identifying renal repair mechanisms and generating replacement kidney tissue. The study of the zebrafish embryonic kidney, or pronephros, provides many opportunities to identify the genes and signaling pathways that control nephron segment development. Here, we describe recent advances of nephron segment patterning and differentiation in the zebrafish, with a focus on distal segment formation.

RELA promotes the progression of oral squamous cell carcinoma via TFAP2A-Wnt/ß-catenin signaling.

Oral squamous cell carcinoma (OSCC) has emerged as the most prevailing oral malignancy worldwide, characterized by cervical solid lymph node metastasis and strong local invasiveness. Overexpression of Transcription Factor AP-2 alpha (TFAP2A) is observed in a significant proportion of OSCC cases. In this study, we aimed to elucidate the function of TFAP2A in the progression of OSCC and the related molecular signaling pathways. The role of RELA was predicted using bioinformatics analysis. The mRNA abundances of RELA, TFAP2A, and ß-catenin were assessed by Western blot and quantitative real-timePCR. The relationship between RELA, TFAP2A, and ß-catenin and their correlation with clinicopathological characteristics of OSCC was evaluated. The target of RELA and TFAP2A was identified by the chromatin immunoprecipitation as well as luciferase reporter assay. The colony formation assay and MTS assay were performed to determine the proliferative level of OSCC cells. OSCC cell motility was determined by Transwell assay and wound-healing assay. The protein expressions of epithelial-mesenchymal transition-associated factors were evaluated by Western blot. The expressions of RELA and TFAP2A were elevated in OSCC, and their expressions displayed a positive correlation. The expression levels of RELA and TFAP2A were found to be associated with TNM staging and lymphatic metastasis of OSCC patients. RELA upregulation promoted OSCC progression, as manifested by increased levels of proliferation, invasion, and migration of OSCC cells. We also demonstrated that RELA was directly bound to the promoter of TFAP2A transcription, which activated multiple malignant and metastatic phenotypes. Furthermore, TFAP2A activated the Wnt/ß-catenin signaling by targeting the promoter regions of ß-catenin. The study found that RELA is critical for promoting the progression of OSCC via the RELA-TFAP2A-Wnt/ß-catenin signaling pathway. The RELA-TFAP2A-Wnt/ß-catenin signaling pathway is a potential target for reducing the aggressiveness of OSCC.

Transcription factor AP-2α activates RNA polymerase III-directed transcription and tumor cell proliferation by controlling expression of c-MYC and p53.

Deregulation of transcription factor AP2 alpha (TFAP2A) and RNA polymerase III (Pol III) products is associated with tumorigenesis. However, the mechanism underlying this event is not fully understood and the connection between TFAP2A and Pol III-directed transcription has not been investigated. Here, we report that TFAP2A functions as a positive factor in the regulation of Pol III-directed transcription and cell proliferation. We found TFAP2A is also required for the activation of Pol III transcription induced by the silencing of filamin A, a well-known cytoskeletal protein and an inhibitor in Pol III-dependent transcription identified previously. Using a chromatin immunoprecipitation technique, we showed TFAP2A positively modulates the assembly of Pol III transcription machinery factors at Pol III-transcribed gene loci. We found TFAP2A can activate the expression of Pol III transcription-related factors, including BRF1, GTF3C2, and c-MYC. Furthermore, we demonstrate TFAP2A enhances expression of MDM2, a negative regulator of tumor suppressor p53, and also inhibits p53 expression. Finally, we found MDM2 overexpression can rescue the inhibition of Pol III-directed transcription and cell proliferation caused by TFAP2A silencing. In summary, we identified that TFAP2A can activate Pol III-directed transcription by controlling multiple pathways, including general transcription factors, c-MYC and MDM2/p53. The findings from this study provide novel insights into the regulatory mechanisms of Pol III-dependent transcription and cancer cell proliferation.

The oncogenic role of TFAP2A in bladder urothelial carcinoma via a novel long noncoding RNA TPRG1-AS1/DNMT3A/CRTAC1 axis.

BACKGROUND: Overexpression of TFAP2A has been linked to increased lymph node metastasis in basal-squamous bladder cancer. However, its downstream targets in bladder urothelial carcinoma (BLCA), the most malignant cancer of the urinary tract, remain unclear. In the current study, we aim to explore the function and mechanism of TFAP2A in BLCA. METHODS: TFAP2A expression and the prognostic significance in BLCA was analyzed using TCGA and GTEX projects. TFAP2A was knocked-down in BLCA cells to study its impact on glucose uptake, lactate and ATP production, expression of HK2, and the number of vascular meshes formed by HUVEC. The target long noncoding RNAs (lncRNAs) of TFAP2A were predicted by bioinformatics tools, followed by ChIP-qPCR and luciferase assays. The downstream targets of TPRG1-AS1 were analyzed by microarray analysis. Rescue experiments were conducted for validation. RESULTS: TFAP2A upregulation in BLCA predicted dismal survival of patients. Loss of TFAP2A inhibited glycolysis (as evidenced by reduced glucose uptake, lactate, ATP production, and the expression of HK2) and angiogenesis (decreased number of vascular meshes formed by HUVEC). TFAP2A promoted the transcription of TPRG1-AS1. TPRG1-AS1 reversed the inhibitory effect of TFAP2A knockdown on glycolysis and angiogenesis in BLCA cells. TPRG1-AS1 inhibited the transcription of CRTAC1 by recruiting a DNA methyltransferase to the promoter of CRTAC1 and increasing the DNA methylation of its promoter. CRTAC1 inhibited glycolysis and angiogenesis in BLCA cells. TFAP2A silencing curbed tumor growth in vivo via the TPRG1-AS1/CRTAC1 axis. CONCLUSION: TFAP2A reduces CRTAC1 expression by promoting TPRG1-AS1 transcription, thereby expediting BLCA glycolysis and angiogenesis.