Search

Objective: To review tumors identified as “clear cell sarcoma” in order to determine similarities to the rare EWS fusion positive jaw and salivary gland tumors clear cell odontogenic carcinoma (CCOC) and clear cell carcinoma of the salivary gland (CCC). Methods: PubMed was used to collect all reports of clear cell sarcoma (CCS). Search parameters were “clear cell sarcoma” and “CCS.” References in the publications were screened and cross-referenced. Data extracted included demographic characteristics, presenting signs and symptoms, radiographic findings, histological and immunohistochemical features and known molecular/genetic aberrations. Results: Clear cell sarcoma has several similarities to CCOC and CCC. All three tumor types have similar histologic appearances including the presence of clear cells, as well as similar genetic profiles in that all harbor an EWSR1-CREB family fusions. Additionally, these tumors appear in soft tissue as well as bone, and can have a prolonged clinical course. CCS can appear anywhere in the body, including the head and neck region. All three tumors appear to have a predilection to women, although CCS may have a slight younger age of onset as compared to CCOC and CCC (3rd vs 5th decade of life, respectively). Conclusion: Gaining a better understanding of the similarities and differences between these three tumors may lead to a better understanding of each one. [ABSTRACT FROM AUTHOR]

'Intracranial mesenchymal tumor, FET-CREB fusion-positive' occurs primarily in children and young adults and has previously been termed intracranial angiomatoid fibrous histiocytoma (AFH) or intracranial myxoid mesenchymal tumor (IMMT). Here we performed genome-wide DNA methylation array profiling of 20 primary intracranial mesenchymal tumors with FET-CREB fusion to further study their ontology. These tumors resolved into two distinct epigenetic subgroups that were both divergent from all other analyzed intracranial neoplasms and soft tissue sarcomas, including meningioma, clear cell sarcoma of soft tissue (CCS), and AFH of extracranial soft tissue. The first subgroup (Group A, 16 tumors) clustered nearest to but independent of solitary fibrous tumor and AFH of extracranial soft tissue, whereas the second epigenetic subgroup (Group B, 4 tumors) clustered nearest to but independent of CCS and also lacked expression of melanocytic markers (HMB45, Melan A, or MITF) characteristic of CCS. Group A tumors most often occurred in adolescence or early adulthood, arose throughout the neuroaxis, and contained mostly EWSR1-ATF1 and EWSR1-CREB1 fusions. Group B tumors arose most often in early childhood, were located along the cerebral convexities or spinal cord, and demonstrated an enrichment for tumors with CREM as the fusion partner (either EWSR1-CREM or FUS-CREM). Group A tumors more often demonstrated stellate/spindle cell morphology and hemangioma-like vasculature, whereas Group B tumors more often demonstrated round cell or epithelioid/rhabdoid morphology without hemangioma-like vasculature, although robust comparison of these clinical and histologic features requires future study. Patients with Group B tumors had inferior progression-free survival relative to Group A tumors (median 4.5 vs. 49 months, p = 0.001). Together, these findings confirm that intracranial AFH-like neoplasms and IMMT represent histologic variants of a single tumor type ('intracranial mesenchymal tumor, FET-CREB fusion-positive') that is distinct from meningioma and extracranial sarcomas. Additionally, epigenomic evaluation may provide important prognostic subtyping for this unique tumor entity.

Clear cell sarcoma of soft tissue is a rare aggressive soft tissue malignancy primarily affecting the extremities of young adults and is characterised by an EWSR1 ::ATF1 fusion gene. The tumour has a high rate of local recurrence and metastasis and as such often has a poor prognosis. [ABSTRACT FROM AUTHOR]

The study aimed to compare 15 cases of mucoepidermoid carcinoma (MEC) and 15 cases of hyalinizing clear cell carcinoma (HCCC) using immunohistochemical staining and molecular analysis. Thirty samples were examined, and markers, including p63, CK5/6, SOX10, CK7, ATF1, and FISH probes specific to EWSR1 and MAML2, were used. Clear cell differentiation was observed in all MEC cases to some extent, with clear cell MEC showing the most prominent findings. Clear cell features were also present in conventional MEC, oncocytic MEC, and Warthin-like MEC, although to a lesser extent. The majority of cases were classified as low-grade MECs. MAML2 rearrangement was detected in all cases (except cases 11 and 14), while EWSR1 rearrangement was observed in a single case of clear cell MEC. These findings helped identify distinct subtypes within the mucoepidermoid carcinoma spectrum. The study emphasized the importance of utilizing immunohistochemical profiles, histopathological features, and molecular analysis for accurate diagnosis and classification of salivary gland neoplasms. HCCC was also discussed, and ATF1 was proposed as a marker to distinguish HCCC from morphologically similar neoplasms. The study concluded that a comprehensive approach combining immunohistochemistry, histopathology, and clinical correlation is essential for accurate diagnosis and classification, considering the variable expression of markers and potential overlap with other tumor types.

Abstract Background Harnessing engineered Mycolicibacteria to convert cheap phytosterols into valuable steroid synthons is a basic way in the industry for the production of steroid hormones. Thus, C-19 and C-22 steroids are the two main types of commercial synthons and the products of C17 side chain degradation of phytosterols. During the conversion process of sterols, C-19 and C-22 steroids are often produced together, although one may be the main product and the other a minor byproduct. This is a major drawback of the engineered Mycolicibacteria for industrial application, which could be attributed to the co-existence of androstene-4-ene-3,17-dione (AD) and 22-hydroxy-23,24-bisnorchol-4-ene-3-one (HBC) sub-pathways in the degradation of the sterol C17 side chain. Since the key mechanism underlying the HBC sub-pathway has not yet been clarified, the above shortcoming has not been resolved so far. Results The key gene involved in the putative HBC sub-pathway was excavated from the genome of M. neoaurum by comparative genomic analysis. Interestingly, an aldolase- encoding gene, atf1, was identified to be responsible for the first reaction of the HBC sub-pathway, and it exists as a conserved operon along with a DUF35-type gene chsH4, a reductase gene chsE6, and a transcriptional regulation gene kstR3 in the genome. Subsequently, atf1 and chsH4 were identified as the key genes involved in the HBC sub-pathway. Therefore, an updated strategy was proposed to develop engineered C-19 or C-22 steroid-producing strains by simultaneously modifying the AD and HBC sub-pathways. Taking the development of 4-HBC and 9-OHAD-producing strains as examples, the improved 4-HBC-producing strain achieved a 20.7 g/L production titer with a 92.5% molar yield and a 56.4% reduction in byproducts, and the improved 9-OHAD producing strain achieved a 19.87 g/L production titer with a 94.6% molar yield and a 43.7% reduction in byproduct production. Conclusions The excellent performances of these strains demonstrated that the primary operon involved in the HBC sub-pathway improves the industrial strains in the conversion of phytosterols to steroid synthons.

Eukaryotic cells are constantly exposed to various environmental stimuli. It remains largely unexplored how environmental cues bring about epigenetic fluctuations and affect heterochromatin stability. In the fission yeast Schizosaccharomyces pombe, heterochromatic silencing is quite stable at pericentromeres but unstable at the mating-type (mat) locus under chronic heat stress, although both loci are within the major constitutive heterochromatin regions. Here, we found that the compromised gene silencing at the mat locus at elevated temperature is linked to the phosphorylation status of Atf1, a member of the ATF/CREB superfamily. Constitutive activation of mitogen-activated protein kinase (MAPK) signaling disrupts epigenetic maintenance of heterochromatin at the mat locus even under normal temperature. Mechanistically, phosphorylation of Atf1 impairs its interaction with heterochromatin protein Swi6HP1, resulting in lower site-specific Swi6HP1 enrichment. Expression of non-phosphorylatable Atf1, tethering Swi6HP1 to the mat3M-flanking site or absence of the anti-silencing factor Epe1 can largely or partially rescue heat stress-induced defective heterochromatic maintenance at the mat locus.

Diffuse intrinsic pontine glioma (DIPG) is a highly aggressive pediatric brain tumor with limited therapeutic options. Here, we investigated the potential of dimethyl alpha-ketoglutarate (DMKG) as an anti-proliferative agent against DIPG and unraveled its underlying molecular mechanisms. DMKG exhibited robust inhibition of DIPG cell proliferation, colony formation, and neurosphere growth. Transcriptomic analysis revealed substantial alterations in gene expression, with upregulated genes enriched in hypoxia-related pathways and downregulated genes associated with cell division and the mitotic cell cycle. Notably, DMKG induced G1/S phase cell cycle arrest and downregulated histone H3 lysine 27 acetylation (H3K27ac) without affecting H3 methylation levels. The inhibition of AKT and ERK signaling pathways by DMKG coincided with decreased expression of the CBP/p300 coactivator. Importantly, we identified the c-MYC-p300/ATF1-p300 axis as a key mediator of DMKG's effects, demonstrating reduced binding to target gene promoters and decreased H3K27ac levels. Depletion of c-MYC or ATF1 effectively inhibited DIPG cell growth. These findings highlight the potent anti-proliferative properties of DMKG, its impact on epigenetic modifications, and the involvement of the c-MYC-p300/ATF1-p300 axis in DIPG, shedding light on potential therapeutic strategies for this devastating disease. • Dimethyl alpha-ketoglutarate inhibits the proliferation and colony formation of diffuse intrinsic pontine glioma. • Dimethyl alpha-ketoglutarate modulates transcriptome associated with cell cycle and cell division. • Dimethyl alpha-ketoglutarate decreases p300-mediated H3K27 acetylation. • Dimethyl alpha-ketoglutarate suppresses c-MYC-p300/ATF1-p300 axis. [ABSTRACT FROM AUTHOR]

Soy sauce, as a traditional seasoning, is widely favoured by Chinese and other Asian people for its unique colour, smell, and taste. In this study, a salt-tolerance Saccharomyces cerevisiae strain HF-130 was obtained via three rounds of ARTP (Atmospheric and Room Temperature Plasma) mutagenesis and high-salt based screening. The ethanol production of mutant HF-130 was increased by 98.8% in very high gravity fermentation. Furthermore, ATF1 gene was overexpressed in strain HF-130, generating ester-producing strain HF-130-ATF1. The ethyl acetate concentration of strain HF-130-ATF1 was increased by 130% compared to the strain HF-130. Finally, the soy sauce fermentation performance of Torulopsis globosa and HF-130-ATF1 was compared with T. globosa, HF-130, HF-130-ATF1, and Torulopsis and HF-130. Results showed ethyl acetate and isoamyl acetate concentrations in co-fermentation of T. globosa and HF-130-ATF1 were increased by 2.8-fold and 3.3-fold, respectively. In addition, the concentrations of ethyl propionate, ethyl caprylate, phenylethyl acetate, ethyl caprate, isobutyl acetate, isoamyl alcohol, phenylethyl alcohol, and phenylacetaldehyde were also improved. Notably, other three important flavour components, trimethylsilyl decyl ester, 2-methylbutanol, and octanoic acid were also detected in the co-fermentation of T. globosa and HF-130-ATF1, but not detected in the control strain T. globosa. This work is of great significance for improving the traditional soy sauce fermentation mode, and thus improving the flavour formation of soy sauce. [ABSTRACT FROM AUTHOR]

The study aimed to compare 15 cases of mucoepidermoid carcinoma (MEC) and 15 cases of hyalinizing clear cell carcinoma (HCCC) using immunohistochemical staining and molecular analysis. Thirty samples were examined, and markers, including p63, CK5/6, SOX10, CK7, ATF1, and FISH probes specific to EWSR1 and MAML2, were used. Clear cell differentiation was observed in all MEC cases to some extent, with clear cell MEC showing the most prominent findings. Clear cell features were also present in conventional MEC, oncocytic MEC, and Warthin-like MEC, although to a lesser extent. The majority of cases were classified as low-grade MECs. MAML2 rearrangement was detected in all cases (except cases 11 and 14), while EWSR1 rearrangement was observed in a single case of clear cell MEC. These findings helped identify distinct subtypes within the mucoepidermoid carcinoma spectrum. The study emphasized the importance of utilizing immunohistochemical profiles, histopathological features, and molecular analysis for accurate diagnosis and classification of salivary gland neoplasms. HCCC was also discussed, and ATF1 was proposed as a marker to distinguish HCCC from morphologically similar neoplasms. The study concluded that a comprehensive approach combining immunohistochemistry, histopathology, and clinical correlation is essential for accurate diagnosis and classification, considering the variable expression of markers and potential overlap with other tumor types. [ABSTRACT FROM AUTHOR]

Background: Harnessing engineered Mycolicibacteria to convert cheap phytosterols into valuable steroid synthons is a basic way in the industry for the production of steroid hormones. Thus, C-19 and C-22 steroids are the two main types of commercial synthons and the products of C17 side chain degradation of phytosterols. During the conversion process of sterols, C-19 and C-22 steroids are often produced together, although one may be the main product and the other a minor byproduct. This is a major drawback of the engineered Mycolicibacteria for industrial application, which could be attributed to the co-existence of androstene-4-ene-3,17-dione (AD) and 22-hydroxy-23,24-bisnorchol-4-ene-3-one (HBC) sub-pathways in the degradation of the sterol C17 side chain. Since the key mechanism underlying the HBC sub-pathway has not yet been clarified, the above shortcoming has not been resolved so far. Results: The key gene involved in the putative HBC sub-pathway was excavated from the genome of M. neoaurum by comparative genomic analysis. Interestingly, an aldolase- encoding gene, atf1, was identified to be responsible for the first reaction of the HBC sub-pathway, and it exists as a conserved operon along with a DUF35-type gene chsH4, a reductase gene chsE6, and a transcriptional regulation gene kstR3 in the genome. Subsequently, atf1 and chsH4 were identified as the key genes involved in the HBC sub-pathway. Therefore, an updated strategy was proposed to develop engineered C-19 or C-22 steroid-producing strains by simultaneously modifying the AD and HBC sub-pathways. Taking the development of 4-HBC and 9-OHAD-producing strains as examples, the improved 4-HBC-producing strain achieved a 20.7 g/L production titer with a 92.5% molar yield and a 56.4% reduction in byproducts, and the improved 9-OHAD producing strain achieved a 19.87 g/L production titer with a 94.6% molar yield and a 43.7% reduction in byproduct production. Conclusions: The excellent performances of these strains demonstrated that the primary operon involved in the HBC sub-pathway improves the industrial strains in the conversion of phytosterols to steroid synthons. [ABSTRACT FROM AUTHOR]

Proinflammatory cytokines such as TNFα mediate airway inflammation. Previously, we showed that TNFα increases mitochondrial biogenesis in human ASM (hASM) cells, which is associated with increased PGC1α expression. We hypothesized that TNFα induces CREB and ATF1 phosphorylation (pCREBS133 and pATF1S63), which transcriptionally co-activate PGC1α expression. Primary hASM cells were dissociated from bronchiolar tissue obtained from patients undergoing lung resection, cultured (one–three passages), and then differentiated by serum deprivation (48 h). hASM cells from the same patient were divided into two groups: TNFα (20 ng/mL) treated for 6 h and untreated controls. Mitochondria were labeled using MitoTracker green and imaged using 3D confocal microscopy to determine mitochondrial volume density. Mitochondrial biogenesis was assessed based on relative mitochondrial DNA (mtDNA) copy number determined by quantitative real-time PCR (qPCR). Gene and/or protein expression of pCREBS133, pATF1S63, PCG1α, and downstream signaling molecules (NRFs, TFAM) that regulate transcription and replication of the mitochondrial genome, were determined by qPCR and/or Western blot. TNFα increased mitochondrial volume density and mitochondrial biogenesis in hASM cells, which was associated with an increase in pCREBS133, pATF1S63 and PCG1α expression, with downstream transcriptional activation of NRF1, NRF2, and TFAM. We conclude that TNFα increases mitochondrial volume density in hASM cells via a pCREBS133/pATF1S63/PCG1α-mediated pathway. [ABSTRACT FROM AUTHOR]

Abstract Background The dynamic balance of osteoblast and osteoclast is critical for bone homeostasis and overactive osteoclastic function may lead to osteoporosis. Activating transcription factor 1 (ATF1) is involved in osteoclastogenesis. However, the detailed mechanisms remain to be explored. Methods RAW264.7 cells were used and induced toward osteoclast by RANKL administration. We performed flow cytometry, CCK-8 assay and tartrate-resistant acid phosphatase (TRAP) staining to examine cell apoptosis, proliferation and differentiation of RAW264.7 cells, respectively. Mice were subjected to ovariectomy to induce osteoporosis. Micro CT, HE staining and TRAP staining were performed to evaluate bone loss in the OVX mouse model. Bioinformatics methods, luciferase assays and Chromatin Immunoprecipitation (ChIP) were used to predict and validate the interaction among ATF1, miR-214-5p, and ITGA7. Results ATF1 and miR-214-5p were up-regulated while ITGA7 was inhibited in RANKL-induced osteoclasts. MiR-214-5p was transcriptionally activated by ATF1. ATF1 knockdown suppressed osteoclast formation by miR-214-5p inhibition. ITGA7 was the direct target of miR-214-5p. Knockdown of miR-214-5p abolished osteoclastogenesis, which was reversed by ITGA7 knockdown. In OVX model, miR-214-5p knockdown suppressed osteoclast differentiation and prevented bone loss. Conclusion ATF1/miR-214-5p/ITGA7 axis regulated osteoclast formation both in vivo and in vitro, thereby affecting OVX-induced bone resorption in mice. Knockdown of ATF1 might be a promising strategy to manage osteoporosis.

Transcription factor ATF1 is a member of the ATF/CREB family of the CREB subfamily and is involved in physiological processes such as tumorigenesis, organ development, reproduction, cell survival, and apoptosis in mammals. However, studies on ATF1 in fish have been relatively poorly reported, especially on its role in antiviral immunity in fish. In this study, ATF1 from orange-spotted grouper (named EcATF1) were cloned and characterized. Molecular characterization analysis showed that EcATF1 encodes a 307-amino-acid protein, containing PKID and bZIP_CREB1 domains. Homology analysis showed that had the highest homology with E. lanceolatus (88.93%). Tissue expression pattern showed that EcATF1 was extensively distributed in twelve selected tissues, with higher expression in the skin, gill, liver and spleen. Subcellular localization analysis showed that EcATF1 was distributed in the nucleus of GS cells. EcATF1 overexpression inhibits Singapore grouper iridovirus (SGIV) and red-spotted grouper nervous necrosis virus (RGNNV) replication, as evidenced by a diminished degree of CPE induced by SGIV and RGNNV and a reduction in the level of viral gene transcription and viral capsid protein expression. Furthermore, EcATF1 overexpression upregulated interferon pathway-related genes and proinflammatory factors, and increased the promoter activities of IFN, IFN stimulated response element (ISRE), and nuclear factor κB(NFκB). Meanwhile, EcATF1 overexpression positive regulate the MHC-I signaling pathway, and upregulated the promoter activity of MHC-I. Collectively, these data demonstrate that EcATF1 plays an important role during the host antiviral immune response. This study provides insights into the function of ATF1 in the immune system of lower vertebrates. • We cloned and characterized ATF1 (EcATF1) from grouper. • EcATF1 inhibit SGIV and RGNNV replication in GS cells. • EcATF1 upregulated IFN pathway and proinflammatory factors. • EcATF1 positive regulate the MHCI pathway. [ABSTRACT FROM AUTHOR]

Background: Cervical cancer (CC) is a common gynecological malignancy with a high risk of recurrence and death. Circular RNAs play a crucial role in the occurrence and development of tumors. This study aimed to investigate the function and mechanism of circ_0000745 in CC. Materials and Methods: The levels of circ_0000745, miR-409-3p, and activating transcription factor 1 (ATF1) were determined by quantitative real-time polymerase chain reaction or Western blot assay. Cell proliferation was assessed by colony formation assay. Cell migration and invasion were evaluated by transwell assay. Glycolysis was analyzed by measuring extracellular acidification rate, glucose uptake, and lactate production. Also, the protein levels of glucose transporter 1 and lactate dehydrogenase A were detected using Western blot. The relationship among circ_0000745, miR-409-3p, and ATF1 were confirmed by dual-luciferase reporter assay. Moreover, xenograft assay was performed to analyze tumor growth in vivo. Results: Circ_0000745 and ATF1 were upregulated, whereas miR-409-3p was downregulated in CC tissues and cells. Knockdown of circ_0000745 repressed proliferation, migration, invasion, and glycolysis of CC cells. Circ_0000745 regulated CC progression by targeting miR-409-3p. Circ_0000745 modulated ATF1 expression through sponging miR-409-3p. MiR-409-3p hindered CC progression by targeting ATF1. Furthermore, depletion of circ_0000745 impeded tumor growth in vivo. Conclusion: Circ_0000745 promoted the progression of CC through modulating miR-409-3p/ATF1 axis, indicating a promising biomarker for CC therapy. [ABSTRACT FROM AUTHOR]

Abstract Background Studies have revealed an important role of activating transcription factor 1 (ATF1) and phosphorylated ATF1 at Ser63 in tumors. Our previous study identified Thr184 as a novel phosphorylation site of ATF1. However, the role of phosphorylated ATF1 at Thr184 (p-ATF1-T184) in tumor is unclear. This study figured out the role of p-ATF1-T184 in the metastasis of gastric cancer (GC) and in the regulation of Matrix metallopeptidase 2 (MMP2). Methods Immunohistochemical analysis (IHC) was performed to analyze the level of p-ATF1-T184 and its relationship with clinicopathological characteristics. Wound scratch test, Transwell assay were used to observe the role of p-ATF1-T184 in the invasion and metastasis of GC. The regulation of MMP2 by p-ATF1-T184 was investigated by a series of experiments including quantitative RT-PCR, western blot, gelatin zymography assay, Chromatin immunoprecipitation (ChIP), luciferase reporter assay and cycloheximide experiment. The Cancer Genome Atlas (TCGA) data were used to analyze the expression and prognostic role of ATF1 and MMP2 in GC. Mass spectrometry (MS) following co-immunoprecipitation (co-IP) assay was performed to identify potential upstream kinases that would phosphorylate ATF1 at Thr184. Results High expression level of p-ATF1-T184 was found and significantly associated with lymph node metastasis and poor survival in a GC cohort of 126 patients. P-ATF1-T184 promoted migration and invasion of gastric cancer cells. Phosphorylation of ATF1-T184 could regulate the mRNA, protein expression and extracellular activity of MMP2. P-ATF1-T184 further increased the DNA binding ability, transcription activity, and stabilized the protein expression of ATF1. Moreover, TCGA data and IHC results suggested that the mRNA level of ATF1 and MMP2, and protein level of p-ATF1-T184 and MMP2 could be prognosis markers of GC. Two protein kinase related genes, LRBA and S100A8, were identified to be correlated with the expression ATF1 in GC. Conclusion Our results indicated that p-ATF1-T184 promoted metastasis of GC by regulating MMP2.

Abstract Background An increasing number of studies have shown that dysregulated miR-589-3p is associated with multiple diseases. However, the role of miR-589-3p in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) remains unknown. This study aimed to explore the biological function and potential molecular mechanism of miR-589-3p in osteogenic differentiation of PDLSCs. Methods GSE159508 was downloaded from Gene Expression Omibus (GEO, http://www.ncbi.nlm.nih.gov/geo/ ). Differentially expressed miRNAs between osteogenic induction PDLSCs versus non-induction PDLSCs were obtained by R software. miR-589-3p mimic and miR-589-3p inhibitor and corresponding negative control were obtained and to identify the role of miR-589-3p in osteogenic differentiation of PDLSCs. ALP staining and ARS were used to evaluate ALP activity and mineralization, respectively. The targeted binding relationship between miR-589-3p and ATF1 was predicted and verified by target prediction analysis and dual-luciferase assay. Furthermore, the functional mechanism based on miR-589-3p and ATF1 in osteogenic differentiation of PDLSCs was further investigated through rescue experiments. Results According to the cut-off criteria with log 2 FC > 1.0 and P

Abstract Background Butyl acetate is a versatile compound that is widely used in the chemical and food industry. The conventional butyl acetate synthesis via Fischer esterification of butanol and acetic acid using catalytic strong acids under high temperature is not environmentally benign. Alternative lipase-catalyzed ester formation requires a significant amount of organic solvent which also presents another environmental challenge. Therefore, a microbial cell factory capable of producing butyl acetate through fermentation of renewable resources would provide a greener approach to butyl acetate production. Result Here, we developed a metabolically engineered strain of Escherichia coli that efficiently converts glucose to butyl acetate. A modified Clostridium CoA-dependent butanol production pathway was used to synthesize butanol which was then condensed with acetyl-CoA through an alcohol acetyltransferase. Optimization of alcohol acetyltransferase expression and redox balance with auto-inducible fermentative controlled gene expression led to an effective titer of 22.8 ± 1.8 g/L butyl acetate produced in a bench-top bioreactor. Conclusion Building on the well-developed Clostridium CoA-dependent butanol biosynthetic pathway, expression of an alcohol acetyltransferase converts the butanol produced into butyl acetate. The results from this study provided a strain of E. coli capable of directly producing butyl acetate from renewable resources at ambient conditions.

Ferroptotic proteins are promising therapeutic targets for lung cancer. The PROM2 is upregulated in lung cancer and known to suppress ferroptosis. This study examined the molecular mechanisms for PROM2-induced ferroptosis resistance in lung cancer. Ferroptosis in lung cancer was assessed by iron kit, and transmission electron microscopy was applied to observe the changes in mitochondrial morphology. BODIPY™ was applied to test the lipid ROS, and MeRIP was performed to test the m6A modification of PROM2. RIP assay was employed for confirming the binding between METTL3 and PROM2. In addition, dual luciferase assay was employed for exploring the transcriptional regulation of ATF1 to METTL3, and the binding relation between ATF1 and METTL3 promoter region was explored by ChIP assay. Expression levels of PROM2 were significantly higher in lung cancer cell lines than a noncancerous control line, and PROM2 knockdown significantly reduced both cancer cell viability and proliferation rate. In addition, PROM2 knockdown reduced xenograft tumor growth and exacerbated erastin-induced ferroptosis. Compared to PROM2 mRNA from control cells, transcripts in lung cancer cells exhibited enhanced m6A levels, and showed greater binding with METTL3. Further, ATF1 upregulated METTL3 transcription, thereby stabilizing PROM2 mRNA and increasing ferroptosis resistance. ATF1 could promote ferroptosis resistance in lung cancer through enhancing mRNA stability of PROM2. Thus, our work might shed novel insights on discovering therapeutic strategy for lung cancer. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Background As a rare salivary gland malignancy, clear cell carcinoma (CCC) is easily misdiagnosed. This study identified the features that allow better recognition of the clinicopathological and molecular characteristics and the prognosis of CCC, focusing on high-grade transformation (HGT) in this tumor and cases arising in uncommon sites. Methods Clinicopathological and follow-up data for 10 CCC samples were retrieved. Immunohistochemical (IHC) staining was performed, and fluorescence in situ hybridization (FISH) was used to detect EWSR1 gene rearrangements, EWSR1–ATF1 gene fusions, and MAML2 gene rearrangements. Results Histologically, typical CCCs comprised bland polygonal or round cells with clear cytoplasm. In contrast with typical CCCs, HGT tumor cells exhibited nuclear pleomorphism, high nuclear-to-cytoplasmic ratios, high mitotic activity, and necrosis. Rare morphologic features such as pseudopapillae, gland-like spaces, and entrapped ducts were also observed. Occasionally, tumors involving the oral cavity might arise from the overlying epithelium of the mucosal surface. Immunohistochemically, all the cases expressed p63, p40, and CK5/6, while myoepithelial-related markers were uniformly negative in all cases. HGT exhibited a wild type p53 expression pattern. FISH demonstrated EWSR1 rearrangement (10/10) and EWSR1–ATF1 fusion (4/5); however, MAML2 remained intact (0/3). Conclusions CCCs with HGT or occurring in uncommon sites are extremely rare. Combining morphology based IHC and molecular detection provided reliable evidence that the HGT component represented a transformation of CCC rather than the coexistence of another tumor and helped differentiating CCCs in uncommon sites from their mimics, avoiding potential misdiagnosis and inappropriate therapy. The overall prognosis for CCCs is good, except for the HGT cases, which needed continued treatment.

DNA methylation is considered to play an important role in the development of diabetic retinopathy. Here, our goal was to investigate the precise role of methyl-CpG binding domain protein 2 (Mbd2) in the apoptosis of retinal ganglion cells (RGCs) in the early diabetic retina. Mbd2 was significantly upregulated after high glucose (HG) treatment and played a proapoptotic role in RGCs during HG-induced apoptosis. Combining ChIP and gene microarray datasets, the results showed that Mbd2 possessed potential binding sites for miR-345-5p, thereby elevating the expression levels of miR-345-5p via the enhancement of promoter demethylation. Activating transcription factor 1 (Atf1) played an anti-apoptotic role during the process of apoptosis in RGCs and acted as the target gene for miR-345-5p. Furthermore, the number of surviving RGCs in the diabetic retina was increased in Mbd2-knockout mice when compared with wild-type mice and the visual function became better accordingly. Collectively, our data demonstrated that the HG-induced overexpression of Mbd2 in the retina was partly responsible for the apoptosis of retinal neuronal cells through the miR-345-5p/Atf1 axis. Therefore, the targeting of Mbd2 might represent a novel therapeutic strategy for the treatment of neurodegeneration in the early diabetic retina.

The stimulus-induced cAMP response element (CRE)-binding protein (CREB) family of transcription factors bind to CREs to regulate diverse cellular responses, including proliferation, survival, and differentiation. Human herpesvirus 6A (HHV-6A), which belongs to the Betaherpesvirinae subfamily, is a lymphotropic herpesvirus frequently found in patients with neuroinflammatory diseases. Previous reports implicated the importance of CREs in the HHV-6A life cycle, although the effects of the binding of transcription factors to CREs in viral replication have not been fully elucidated. In this study, we analyzed the role of the CREB family of transcription factors during HHV-6A replication. We found that HHV-6A infection enhanced phosphorylation of the CREB family members CREB1 and activating transcription factor 1 (ATF1). Knockout (KO) of CREB1 or ATF1 enhanced viral gene expression and viral replication. The increase in viral yields in supernatants from ATF1-KO cells was greater than that in supernatants from CREB1-KO cells. Transcriptome sequencing (RNA-seq) analysis showed that sensors of the innate immune system were downregulated in ATF1-KO cells, and mRNAs of beta interferon (IFN-β) and IFN-regulated genes were reduced in these cells infected with HHV-6A. IFN-β treatment of ATF1-KO cells reduced progeny viral yields significantly, suggesting that the enhancement of viral replication was caused by a reduction of IFN-β. Taken together, our results suggest that ATF1 is activated during HHV-6A infection and restricts viral replication via IFNb induction. IMPORTANCE Human herpesvirus 6A (HHV-6A) is a ubiquitous herpesvirus implicated in Alzheimer's disease, although its role in its pathogenesis has not been confirmed. Here, we showed that the transcription factor ATF1 restricts HHV-6A replication, mediated by IFN-β induction. Our study provides new insights into the role of ATF1 in innate viral immunity and reveals the importance of IFN-β for regulation of HHV-6A replication, which possibly impairs HHV-6A pathogenesis. [ABSTRACT FROM AUTHOR]

The bZIP transcription factor Atf1 is a key player in the transcriptional programme of Schizosaccharomyces pombe cell cycle. It also controls both expression and degradation of mitotic cyclin Cdc13. Temporal regulation of these opposing functions of Atf1 is critical for fidelity of cell division. Our investigations revealed that an increase in the activity of mitogen‐activated protein kinase (MAPK) Spc1 during mitotic exit and the consequent phosphorylation of Atf1 along with the prevailing high activity of cyclin‐dependent kinase Cdc2 regulate Cdc13 degradation. Our results also indicate the possibility of a complex interplay between Cdc2 inhibitory kinase Wee1, the anaphase‐promoting complex and Atf1 during mitotic exit. These observations provide evidence of new regulatory mechanisms of mitotic exit. [ABSTRACT FROM AUTHOR]

Malignant gastrointestinal neuroectodermal tumor (MGNET) is a sarcoma typically involving the gastrointestinal tract with neuroectodermal differentiation and EWSR1-ATF1/CREB1 fusions. Recently, rare MGNET cases were reported in extragastrointestinal sites. We identified 2 cases of MGNET arising in unprecedented laryngeal and intracranial locations, respectively. Both cases showed spindle and epithelioid tumor cells with amphophilic to clear cytoplasm and occasionally prominent nucleoli, arranged in solid, fascicular, and pseudoalveolar patterns. Case 1 exhibited moderate to marked nuclear atypia and focal intraepithelial component. In contrast, case 2 comprised predominantly low-grade epithelioid cells with extensive pseudopapillary structures. Both tumors showed an S100/SOX10-positive and HMB45/melan-A-negative immunoprofile as well as EWSR1-ATF1 fusion. A chief obstacle in diagnosing case 1 was the histologic and immunophenotypic resemblance to melanoma. The striking pseudopapillary architecture and the intracranial location of case 2 rendered differential diagnoses including meningioma and ependymoma. With the peculiar locations and morphology, these cases posed great diagnostic challenge. [ABSTRACT FROM AUTHOR]

Clear cell carcinoma (CCC) is a rare epithelial malignant tumor of the salivary glands. It is characterized by tumor cells with clear cytoplasm, hyalinized stroma, and most importantly the fusion genes EWSR1-ATF1, EWSR1-CREM, and EWSR1-PLAG1. Break-apart FISH has been performed for multiple CCC cases, but direct sequencing analysis has been performed in relatively few. Herein, we report an interesting case of CCC harboring three EWSR1-ATF1 translocations: EWSR1 exon 8-ATF1 exon 4, EWSR1 exon 7-ATF1 exon 4, and EWSR1 exon 7-ATF1 exon 5. This case indicates the possibility of independent EWSR1-ATF1 gene translocations, and could provide insight into CCC tumorgenesis. [ABSTRACT FROM AUTHOR]

Background: The dynamic balance of osteoblast and osteoclast is critical for bone homeostasis and overactive osteoclastic function may lead to osteoporosis. Activating transcription factor 1 (ATF1) is involved in osteoclastogenesis. However, the detailed mechanisms remain to be explored. Methods: RAW264.7 cells were used and induced toward osteoclast by RANKL administration. We performed flow cytometry, CCK-8 assay and tartrate-resistant acid phosphatase (TRAP) staining to examine cell apoptosis, proliferation and differentiation of RAW264.7 cells, respectively. Mice were subjected to ovariectomy to induce osteoporosis. Micro CT, HE staining and TRAP staining were performed to evaluate bone loss in the OVX mouse model. Bioinformatics methods, luciferase assays and Chromatin Immunoprecipitation (ChIP) were used to predict and validate the interaction among ATF1, miR-214-5p, and ITGA7. Results: ATF1 and miR-214-5p were up-regulated while ITGA7 was inhibited in RANKL-induced osteoclasts. MiR-214-5p was transcriptionally activated by ATF1. ATF1 knockdown suppressed osteoclast formation by miR-214-5p inhibition. ITGA7 was the direct target of miR-214-5p. Knockdown of miR-214-5p abolished osteoclastogenesis, which was reversed by ITGA7 knockdown. In OVX model, miR-214-5p knockdown suppressed osteoclast differentiation and prevented bone loss. Conclusion: ATF1/miR-214-5p/ITGA7 axis regulated osteoclast formation both in vivo and in vitro, thereby affecting OVX-induced bone resorption in mice. Knockdown of ATF1 might be a promising strategy to manage osteoporosis. [ABSTRACT FROM AUTHOR]

Schizosaccharomyces pombe has been used as an excellent model for studying eukaryotic cell cycle regulation and stress responses. The bZIP transcription factors Atf1(ATF2 homolog) and Pcr1(CREB homolog) have been shown to be important for regulating the expression of genes related to both stress response and cell cycle. Pcr1 has in fact been implicated as a determining factor in the segregation of the cell cycle and stress response related functions of Atf1. Interestingly Atf1 and Pcr1 levels are known to vary during the cell cycle thus giving rise to the possibility that their relative levels can influence the periodic transcriptional program of the cell. Here we report our observations on the changes in transcriptome of S. pombe cells which have been genetically manipulated to create relative differences in the levels of Atf1 and Pcr1. These results highlight new information regarding the potential role of Atf1 and Pcr1 in orchestrating the integration of the transcriptional programs of cell cycle and stress response.

Proinflammatory cytokines such as TNFα mediate airway inflammation. Previously, we showed that TNFα increases mitochondrial biogenesis in human ASM (hASM) cells, which is associated with increased PGC1α expression. We hypothesized that TNFα induces CREB and ATF1 phosphorylation (pCREBS133 and pATF1S63), which transcriptionally co-activate PGC1α expression. Primary hASM cells were dissociated from bronchiolar tissue obtained from patients undergoing lung resection, cultured (one–three passages), and then differentiated by serum deprivation (48 h). hASM cells from the same patient were divided into two groups: TNFα (20 ng/mL) treated for 6 h and untreated controls. Mitochondria were labeled using MitoTracker green and imaged using 3D confocal microscopy to determine mitochondrial volume density. Mitochondrial biogenesis was assessed based on relative mitochondrial DNA (mtDNA) copy number determined by quantitative real-time PCR (qPCR). Gene and/or protein expression of pCREBS133, pATF1S63, PCG1α, and downstream signaling molecules (NRFs, TFAM) that regulate transcription and replication of the mitochondrial genome, were determined by qPCR and/or Western blot. TNFα increased mitochondrial volume density and mitochondrial biogenesis in hASM cells, which was associated with an increase in pCREBS133, pATF1S63 and PCG1α expression, with downstream transcriptional activation of NRF1, NRF2, and TFAM. We conclude that TNFα increases mitochondrial volume density in hASM cells via a pCREBS133/pATF1S63/PCG1α-mediated pathway.

Background: An increasing number of studies have shown that dysregulated miR-589-3p is associated with multiple diseases. However, the role of miR-589-3p in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) remains unknown. This study aimed to explore the biological function and potential molecular mechanism of miR-589-3p in osteogenic differentiation of PDLSCs. Methods: GSE159508 was downloaded from Gene Expression Omibus (GEO, http://www.ncbi.nlm.nih.gov/geo/). Differentially expressed miRNAs between osteogenic induction PDLSCs versus non-induction PDLSCs were obtained by R software. miR-589-3p mimic and miR-589-3p inhibitor and corresponding negative control were obtained and to identify the role of miR-589-3p in osteogenic differentiation of PDLSCs. ALP staining and ARS were used to evaluate ALP activity and mineralization, respectively. The targeted binding relationship between miR-589-3p and ATF1 was predicted and verified by target prediction analysis and dual-luciferase assay. Furthermore, the functional mechanism based on miR-589-3p and ATF1 in osteogenic differentiation of PDLSCs was further investigated through rescue experiments. Results: According to the cut-off criteria with log 2 FC > 1.0 and P < 0.05, 514 differentially expressed miRNAs were identified between osteogenic induction and non-induction PDLSCs, including 309 upregulated miRNAs and 205 downregulated miRNAs. Compared with control PDLSCs, miR-589-3p expression level was notably increased in PDLSCs that underwent osteogenic induction. The overexpression of miR-589-3p promoted the cell viability of PDLSCs, while the low expression of miR-589-3p had the opposite effect. The dual luciferase reporter assay verified that ATF1 was proved to be a direct target of miR-589-3p in PDLSCs. And overexpressed miR-589-3p reduced the expression of ATF1. Overexpression of miR-589-3p enhanced the osteogenic capacity of PDLSCs, as demonstrated by increases in ALP activity, matrix mineralization, and RUNX2, OCN and OSX expression. In addition, the rescue experiments confirmed that overexpressed ATF1 restored the effects of overexpressed miR-589-3p on cell proliferation and osteogenic differentiation of PDLSCs. Conclusion: miR-589-3p could down-regulate the expression of ATF1, thereby promote the proliferation and osteogenic differentiation of PDLSCs. This finding may provide a new therapeutic target for molecular therapy of periodontitis. [ABSTRACT FROM AUTHOR]

Background: Studies have revealed an important role of activating transcription factor 1 (ATF1) and phosphorylated ATF1 at Ser63 in tumors. Our previous study identified Thr184 as a novel phosphorylation site of ATF1. However, the role of phosphorylated ATF1 at Thr184 (p-ATF1-T184) in tumor is unclear. This study figured out the role of p-ATF1-T184 in the metastasis of gastric cancer (GC) and in the regulation of Matrix metallopeptidase 2 (MMP2).Methods: Immunohistochemical analysis (IHC) was performed to analyze the level of p-ATF1-T184 and its relationship with clinicopathological characteristics. Wound scratch test, Transwell assay were used to observe the role of p-ATF1-T184 in the invasion and metastasis of GC. The regulation of MMP2 by p-ATF1-T184 was investigated by a series of experiments including quantitative RT-PCR, western blot, gelatin zymography assay, Chromatin immunoprecipitation (ChIP), luciferase reporter assay and cycloheximide experiment. The Cancer Genome Atlas (TCGA) data were used to analyze the expression and prognostic role of ATF1 and MMP2 in GC. Mass spectrometry (MS) following co-immunoprecipitation (co-IP) assay was performed to identify potential upstream kinases that would phosphorylate ATF1 at Thr184.Results: High expression level of p-ATF1-T184 was found and significantly associated with lymph node metastasis and poor survival in a GC cohort of 126 patients. P-ATF1-T184 promoted migration and invasion of gastric cancer cells. Phosphorylation of ATF1-T184 could regulate the mRNA, protein expression and extracellular activity of MMP2. P-ATF1-T184 further increased the DNA binding ability, transcription activity, and stabilized the protein expression of ATF1. Moreover, TCGA data and IHC results suggested that the mRNA level of ATF1 and MMP2, and protein level of p-ATF1-T184 and MMP2 could be prognosis markers of GC. Two protein kinase related genes, LRBA and S100A8, were identified to be correlated with the expression ATF1 in GC.Conclusion: Our results indicated that p-ATF1-T184 promoted metastasis of GC by regulating MMP2. [ABSTRACT FROM AUTHOR]

Background: Butyl acetate is a versatile compound that is widely used in the chemical and food industry. The conventional butyl acetate synthesis via Fischer esterification of butanol and acetic acid using catalytic strong acids under high temperature is not environmentally benign. Alternative lipase-catalyzed ester formation requires a significant amount of organic solvent which also presents another environmental challenge. Therefore, a microbial cell factory capable of producing butyl acetate through fermentation of renewable resources would provide a greener approach to butyl acetate production. Result: Here, we developed a metabolically engineered strain of Escherichia coli that efficiently converts glucose to butyl acetate. A modified Clostridium CoA-dependent butanol production pathway was used to synthesize butanol which was then condensed with acetyl-CoA through an alcohol acetyltransferase. Optimization of alcohol acetyltransferase expression and redox balance with auto-inducible fermentative controlled gene expression led to an effective titer of 22.8 ± 1.8 g/L butyl acetate produced in a bench-top bioreactor. Conclusion: Building on the well-developed Clostridium CoA-dependent butanol biosynthetic pathway, expression of an alcohol acetyltransferase converts the butanol produced into butyl acetate. The results from this study provided a strain of E. coli capable of directly producing butyl acetate from renewable resources at ambient conditions. [ABSTRACT FROM AUTHOR]

Background: As a rare salivary gland malignancy, clear cell carcinoma (CCC) is easily misdiagnosed. This study identified the features that allow better recognition of the clinicopathological and molecular characteristics and the prognosis of CCC, focusing on high-grade transformation (HGT) in this tumor and cases arising in uncommon sites. Methods: Clinicopathological and follow-up data for 10 CCC samples were retrieved. Immunohistochemical (IHC) staining was performed, and fluorescence in situ hybridization (FISH) was used to detect EWSR1 gene rearrangements, EWSR1–ATF1 gene fusions, and MAML2 gene rearrangements. Results: Histologically, typical CCCs comprised bland polygonal or round cells with clear cytoplasm. In contrast with typical CCCs, HGT tumor cells exhibited nuclear pleomorphism, high nuclear-to-cytoplasmic ratios, high mitotic activity, and necrosis. Rare morphologic features such as pseudopapillae, gland-like spaces, and entrapped ducts were also observed. Occasionally, tumors involving the oral cavity might arise from the overlying epithelium of the mucosal surface. Immunohistochemically, all the cases expressed p63, p40, and CK5/6, while myoepithelial-related markers were uniformly negative in all cases. HGT exhibited a wild type p53 expression pattern. FISH demonstrated EWSR1 rearrangement (10/10) and EWSR1–ATF1 fusion (4/5); however, MAML2 remained intact (0/3). Conclusions: CCCs with HGT or occurring in uncommon sites are extremely rare. Combining morphology based IHC and molecular detection provided reliable evidence that the HGT component represented a transformation of CCC rather than the coexistence of another tumor and helped differentiating CCCs in uncommon sites from their mimics, avoiding potential misdiagnosis and inappropriate therapy. The overall prognosis for CCCs is good, except for the HGT cases, which needed continued treatment. [ABSTRACT FROM AUTHOR]

Short-chain esters have broad utility as flavors, fragrances, solvents, and biofuels. Controlling selectivity of ester microbial biosynthesis has been an outstanding metabolic engineering problem. In this study, we enabled the de novo fermentative microbial biosynthesis of butyryl-CoA-derived designer esters (e.g., butyl acetate, ethyl butyrate, butyl butyrate) in Escherichia coli with controllable selectivity. Using the modular design principles, we generated the butyryl-CoA-derived ester pathways as exchangeable production modules compatible with an engineered chassis cell for anaerobic production of designer esters. We designed these modules derived from an acyl-CoA submodule (e.g., acetyl-CoA, butyryl-CoA), an alcohol submodule (e.g., ethanol, butanol), a cofactor regeneration submodule (e.g., NADH), and an alcohol acetyltransferase (AAT) submodule (e.g., ATF1, SAAT) for rapid module construction and optimization by manipulating replication (e.g., plasmid copy number), transcription (e.g., promoters), translation (e.g., codon optimization), pathway enzymes, and pathway induction conditions. To further enhance production of designer esters with high selectivity, we systematically screened various strategies of protein solubilization using protein fusion tags and chaperones to improve the soluble expression of multiple pathway enzymes. Finally, our engineered ester-producing strains could achieve 19-fold increase in butyl acetate production (0.64 g/L, 96% selectivity), 6-fold increase in ethyl butyrate production (0.41 g/L, 86% selectivity), and 13-fold increase in butyl butyrate production (0.45 g/L, 54% selectivity) as compared to the initial strains. Overall, this study presented a generalizable framework to engineer modular microbial platforms for anaerobic production of butyryl-CoA-derived designer esters from renewable feedstocks. • Developed a generalizable framework to engineer a modular microbial platform for anaerobic production of designer esters. • Engineered the de novo modular fermentative pathways for selective biosynthesis of butyryl-CoA-derived esters in E. coli. • Manipulated replication, transcription, and (post)translation to tune the metabolic fluxes of the ester production modules. • Implemented various protein solubilization strategies on aggregate-prone pathway enzymes for selective ester production. • Demonstrated modular microbial biosynthesis of butyryl-CoA-derived esters from glucose with high (up to >96%) selectivity. [ABSTRACT FROM AUTHOR]

Malignant mesothelioma with EWSR1-ATF1 fusion is a rare malignancy described in young adults without asbestos exposure. To the best of our knowledge, outcomes to local and systemic therapies for this subtype of malignant mesothelioma have not been described. This case report describes the clinical course of a 19-year-old man diagnosed with malignant peritoneal mesothelioma with EWSR1-ATF1 fusion localized to the abdomen. His disease followed an aggressive course and resulted in limited survival (18 mo). There was treatment resistance to several lines of conventional local and systemic treatments for peritoneal mesothelioma and biologically targeted MET inhibition with crizotinib. More research is required in this rare subtype of peritoneal mesothelioma.

Soft tissue neoplasms, harboring fusions between EWSR1 and FUS with genes encoding CREB transcription factors family (ATF1, CREB1, and CREM), are an emerging heterogeneous group of mesenchymal tumors that differ significantly in morphology, immunophenotypes, and behavior. Recently, EWSR1/FUS::CREB fusions have been recognized to define a group of aggressive neoplasms of epithelioid morphology with multiple growth patterns and a striking predilection for mesothelial-lined cavities. These neoplasms presenting as a primary neoplasm of intra-abdominal visceral organs are rare, which could elicit a wide range of differential diagnoses because of their diverse morphologies and immunohistochemical profiles. We report 3 cases of intra-abdominal epithelioid neoplasms with EWSR1::CREB fusions involving the kidney. This study included 2 female patients and 1 male patient, with age at presentation ranging from 17 to 61 years (mean: 32 years). All the patients underwent radical nephrectomy without adjunctive therapies. Grossly, the tumors were large, and all were solitary masses with sizes ranging from 5.6 to 30.0 cm (mean: 14.5 cm). Histologically, the neoplasms showed infiltrating and indistinct borders and were composed predominantly of monomorphic round-to-epithelioid cells with variable amounts of pale-to-clear cytoplasm, arranged in cords, nests, and sheets and embedded in a sclerotic hyalinized stroma with variable lymphoid cuffing either intermixed or at the periphery. Notably, a hemangiopericytomatous growth pattern was commonly seen. Nuclear atypia was mild, and mitotic activity was scarce. Immunohistochemically, all 3 cases were at least focally positive for epithelial membrane antigen and keratin AE1/AE3, with 2 tumors showing focal MUC4 expression and 1 case displaying diffuse CD34 and focal CAIX positivity. Targeted RNA sequencing identified EWSR1::CREM fusion in 2 cases and EWSR1::ATF1 fusion in 1 case. Subsequent fluorescence in situ hybridization analysis confirmed the RNA sequencing results. On follow-up, 1 patient developed multiple spinal bone metastases 5 months after the surgery while the other 2 patients were free of disease 9 and 120 months after diagnosis, respectively. Our findings demonstrate that intra-abdominal epithelioid neoplasms with EWSR1::CREB fusions may rarely occur primarily in the kidney and should be included in the differential diagnosis of primary renal epithelioid mesenchymal neoplasms., (Copyright © 2024 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.)

The activating transcription factor 1 (ATF1) has been identified as a vital pathogenic factor in the progression of colorectal cancer (CRC), whiles, the precise regulatory mechanisms remain elusive. Here, we comprehensively characterized the ATF1 cistrome by RNA-seq and ChIP-seq assays in CRC cell lines. As the results, we identified 358 genes differentially regulated and 15,029 ATF1 binding sites and demonstrated that ATF1 was widely involved in major signaling pathways in CRC, such as Wnt, TNF, Jak-STAT. Subsequently, by the expression quantitative trait loci (eQTL) analyses, we found that rs7017386 was associated with the expression of CCAT1 and PVT1 in the Wnt pathway. By a two-stage population study with 6,131 CRC cases and 10,022 healthy controls, we identified the variant was associated with CRC risk. Mechanistically, we found rs7017386 allele-specifically enhanced the binding affinity of ATF1 and promoted the expressions of PVT1 and CCAT1, via forming a long-range chromatin loop. Moreover, those two lncRNAs could synergistically facilitate c-Myc expression to activate the Wnt pathway in CRC progression. Our findings not only demonstrated the transcriptomic profiling of ATF1 in CRC, but also provided important clues for the etiology of CRC. [ABSTRACT FROM AUTHOR]

We recently described novel dermal tumors with melanocytic differentiation and morphologic and biological similarities to cutaneous clear cell sarcoma, including CRTC1::TRIM11 cutaneous tumor, and clear cell tumors with melanocytic differentiation and either ACTIN::MITF or MITF::CREM. Here, we describe a series of 3 patients presenting with tumors reminiscent of CRTC1::TRIM11 cutaneous tumor, found to demonstrate a novel MED15::ATF1 fusion. All 3 patients were children (5-16 years old). Primary excision of case 1 showed a circumscribed wedge-shaped silhouette with peripheral intercalation into collagen fibers and scattered lymphoid aggregates. All 3 tumors abutted the epidermis; one showed a junctional component. Tumors were highly cellular and comprised of monomorphic, oval-to-round epithelioid cells arranged in vague nests and short fascicles in variably fibrotic stroma. Mitotic rate was high (hotspot 6-12/mm 2 ), without atypical mitoses. Necrosis was focally present in case 3. All cases showed strong, diffuse nuclear staining for SOX10 and MITF (2/2) but showed variable expression for S100 protein (1/3) and other melanocytic markers-Melan-A (focal in 2/3), HMB45 (focal in 1/3), and Pan-Melanoma (patchy in 1/1). Whole-exome RNA sequencing demonstrated a MED15::ATF1 fusion without any other notable alterations. Cases 1 and 2 were completely excised without recurrence (12 months). Case 3 developed a grossly apparent regional lymph node spread shortly after primary biopsy. The patient was treated with wide excision, radiation, cervical lymph node dissection (4/46 with >75% lymph node replacement), and neoadjuvant and adjuvant nivolumab (alive without disease at cycle 11). This series is presented to aid in future diagnosis of this novel dermal tumor with melanocytic differentiation and emphasize the potential for aggressive biologic behavior, which should be considered in patient management planning., (Copyright © 2024 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.)

Childhood melanoma is a rare and biologically heterogeneous pediatric malignancy. The differential diagnosis of pediatric melanoma is usually broad, including a wide variety of spindle cell or epithelioid neoplasms. Different molecular alterations affecting the MAPK and PI3K/AKT/mTOR pathways, tumor suppressor genes, and telomerase reactivation have been implicated in melanoma tumorigenesis and progression. Here, we report a novel MED15::ATF1 fusion in a pediatric melanoma with spitzoid features and an aggressive clinical course., (© 2024 Wiley Periodicals LLC.)

Background: Periodontitis is a chronic inflammatory disease resulting from bacterial plaque infection. While the involvement of activating transcription factor 1 (ATF1) has been extensively explored in various human diseases, its specific role in periodontitis remains unclear. This study aims to elucidate the expression and biological function of ATF1 in the context of periodontitis., Methods: Primary human periodontal ligament cells (hPDLCs) were procured from clinical samples and subsequently characterized. Following treatment with P . gingivalis lipopolysaccharide (LPS, 10 μg/mL), hPDLCs underwent transfection with either ATF1 vector or siRNA. The expression levels of ATF1 in LPS-treated hPDLCs or transfected cells were evaluated through real-time quantitative polymerase chain reaction (RT-qPCR) and western blot assay. Inflammatory factors, including interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1β), were quantified using Enzyme-linked Immunosorbent Assay (ELISA). The assessment of osteogenic proteins, such as runt-related transcription factor 2 (Runx2), osteopontin (OPN), and osteoprotegerin (OPG), as well as noncanonical nuclear factor-kappaB (NF-κB) pathway-related proteins (p65, p-p65, IkBα, p-IkBα), was conducted using western blot assay. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry assays were employed to detect cell viability., Results: LPS induced an inflammatory response and hindered the osteogenic differentiation of hPDLCs ( p < 0.05, p < 0.01). Furthermore, ATF1 silencing enhanced cell proliferation and suppressed apoptosis in LPS-stimulated hPDLCs ( p < 0.05, p < 0.01). ATF1 silencing not only restrained the inflammatory response but also promoted the osteogenic differentiation of LPS-stimulated hPDLCs ( p < 0.05, p < 0.01). Importantly, ATF1 silencing effectively blocked the LPS-induced activation of the NF-κB signaling pathway ( p < 0.05, p < 0.01, p < 0.001)., Conclusions: ATF1 emerges as a promising treatment option, inhibiting the osteogenic differentiation of hPDLCs and mitigating the inflammatory response by preventing the phosphorylation of the NF-κB signaling pathway.

Eukaryotic cells are constantly exposed to various environmental stimuli. It remains largely unexplored how environmental cues bring about epigenetic fluctuations and affect heterochromatin stability. In the fission yeast Schizosaccharomyces pombe , heterochromatic silencing is quite stable at pericentromeres but unstable at the mating-type ( mat ) locus under chronic heat stress, although both loci are within the major constitutive heterochromatin regions. Here, we found that the compromised gene silencing at the mat locus at elevated temperature is linked to the phosphorylation status of Atf1, a member of the ATF/CREB superfamily. Constitutive activation of mitogen-activated protein kinase (MAPK) signaling disrupts epigenetic maintenance of heterochromatin at the mat locus even under normal temperature. Mechanistically, phosphorylation of Atf1 impairs its interaction with heterochromatin protein Swi6 HP1 , resulting in lower site-specific Swi6 HP1 enrichment. Expression of non-phosphorylatable Atf1, tethering Swi6 HP1 to the mat3M -flanking site or absence of the anti-silencing factor Epe1 can largely or partially rescue heat stress-induced defective heterochromatic maintenance at the mat locus., Competing Interests: LS, LL, CS, YW, QJ No competing interests declared, (© 2024, Sun, Liu, Song et al.)

Background: Glioblastoma (GBM) is a fast-growing primary brain tumor characterized by high invasiveness and resistance. This results in poor patient survival. Resistance is caused by many factors, including cell-extracellular matrix (ECM) interactions. Here, we addressed the role of adhesion protein integrin α2, which we identified in a high-throughput screen for novel potential targets in GBM cells treated with standard therapy consisting of temozolomide (TMZ) and radiation., Methods: In our study, we used a range of primary/stem-like and established GBM cell models in vitro and in vivo. To identify regulatory mechanisms, we employed high-throughput kinome profiling, Western blotting, immunofluorescence staining, reporter, and activity assays., Results: Our data showed that integrin α2 is overexpressed in GBM compared to normal brain and, that its deletion causes radiochemosensitization. Similarly, invasion and adhesion were significantly reduced in TMZ-irradiated GBM cell models. Furthermore, we found that integrin α2-knockdown impairs the proliferation of GBM cells without affecting DNA damage repair. At the mechanistic level, we found that integrin α2 affects the activity of activating transcription factor 1 (ATF1) and modulates the expression of extracellular signal-regulated kinase 1 (ERK1) regulated by extracellular signals. Finally, we demonstrated that integrin α2-deficiency inhibits tumor growth and thereby prolongs the survival of mice with orthotopically growing GBM xenografts., Conclusions: Taken together our data suggest that integrin α2 may be a promising target to overcome GBM resistance to radio- and chemotherapy. Thus, it would be worth evaluating how efficient and safe the adjuvant use of integrin α2 inhibitors is to standard radio(chemo)therapy in GBM., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

[Display omitted] Uremic toxins, such as p -cresyl sulfate (PCS) and indoxyl sulfate (IS), contribute to endothelial dysfunction in chronic kidney disease (CKD). This process is mediated by several cellular pathways, but it is unclear whether cAMP-responsive element-binding protein (CREB) and activating transcription factor 1 (ATF1) participate in endothelial dysfunction in uremic conditions despite playing roles in inflammatory modulation. This study aimed to evaluate the expression, activation, and transcriptional activity of CREB/ATF1 in endothelial cells exposed to PCS, IS, and uremic serum (US). In vitro , ATF1 protein levels were increased by PCS and IS, whereas CREB levels were enhanced only by IS. Activation through CREB-Ser133 and ATF1-Ser63 phosphorylation was induced by PCS, IS, and US. We evaluated the CREB/ATF1 transcriptional activity by analyzing the expression of their target genes, including ICAM1 , PTGS2 , NOX1 , and SLC22A6 , which are related to endothelial dysfunction through their roles in vascular inflammation, oxidative stress, and cellular uptake of PCS and IS. The expression of ICAM1 , PTGS2 and NOX1 genes was increased by PCS, IS, and US, whereas that of SLC22A6 was induced only by IS. KG-501, a CREB inhibitor, restored the inductive effects of PCS on ICAM1 , PTGS2 , and NOX1 expression; IS on ICAM1 , PTGS2 and SLC22A6 expression; and US on NOX1 expression. The presence of CREB and ATF1 was observed in healthy arteries and in arteries of patients with CKD, which were structurally damaged. These findings suggest that CREB/ATF1 is activated by uremic toxins and may play a relevant role in endothelial dysfunction in CKD. [ABSTRACT FROM AUTHOR]