Chidamide enhances T-cell-mediated anti-tumor immune function by inhibiting NOTCH1/NFATC1 signaling pathway in ABC-type diffuse large B-cell lymphoma

Chidamide (CS055/HBI-8000, tucidinostat) has shown promising effects in the clinical treatment of various hematologic tumors. Diffuse large B-cell lymphoma (DLBCL) has shown highly heterogeneous biological characteristics. There are complex mechanisms of the role of chidamide in DLBCL for in-depth study. It is essential to probe further into the mechanism of drug-tumor interactions as a guide to clinical application and to understand the occurrence and progression of DLBCL. In vitro and in vivo models were utilized to determine the effects of chidamide on signaling pathways involved in the DLBCL tumor microenvironment. The experimental results show that chidamide inhibited the proliferation of DLBCL cell lines in a dose- and time-dependent manner, and down-regulated the expression of NOTCH1 and NFATC1 in DLBCL cells as well as decreased the concentration of IL-10 in the supernatant. In addition, chidamide significantly lowered the expression of PD1 or TIM3 on CD4+T cells and CD8+T cells and elevated the levels of IL-2, IFN-γ, and TNF-α in the serum of animal models, which augmented the function of circulating T cells and tumor-infiltrating T cells and ultimately significantly repressed the growth of tumors. These findings prove that chidamide can effectively inhibit the cell activity of DLBCL cell lines by inhibiting the activation of NOTCH1 and NFATC1 signaling pathways. It can also improve the abnormal DLBCL microenvironment in which immune escape occurs, and inhibit immune escape. This study provides a new therapeutic idea for the exploration of individualized precision therapy for patients with malignant lymphoma.

The Impact of 3D Nichoids and Matrix Stiffness on Primary Malignant Mesothelioma Cells

Malignant mesothelioma is a type of cancer that affects the mesothelium. It is an aggressive and deadly form of cancer that is often caused by exposure to asbestos. At the molecular level, it is characterized by a low number of genetic mutations and high heterogeneity among patients. In this work, we analyzed the plasticity of gene expression of primary mesothelial cancer cells by comparing their properties on 2D versus 3D surfaces. First, we derived from primary human samples four independent primary cancer cells. Then, we used Nichoids, which are micro-engineered 3D substrates, as three-dimensional structures. Nichoids limit the dimension of adhering cells during expansion by counteracting cell migration between adjacent units of a substrate with their microarchitecture. Tumor cells grow effectively on Nichoids, where they show enhanced proliferation. We performed RNAseq analyses on all the samples and compared the gene expression pattern of Nichoid-grown tumor cells to that of cells grown in a 2D culture. The PCA analysis showed that 3D samples were more transcriptionally similar compared to the 2D ones. The 3D Nichoids induced a transcriptional remodeling that affected mainly genes involved in extracellular matrix assembly. Among these genes responsible for collagen formation, COL1A1 and COL5A1 exhibited elevated expression, suggesting changes in matrix stiffness. Overall, our data show that primary mesothelioma cells can be effectively expanded in Nichoids and that 3D growth affects the cells' tensegrity or the mechanical stability of their structure.

Thymic Carcinoma: Unraveling Neuroendocrine Differentiation and Epithelial Cell Identity Loss

BACKGROUND

The histogenesis of thymic epithelial tumors (TETs) has been a subject of debate. Recent technological advancements have revealed that thymic carcinomas often exhibit a phenotype akin to tuft cells, which is a subset of medullary TECs. Here, we further explored the gene expression signatures of thymic carcinomas in relation to tuft cells and their kinships-ionocytes and neuroendocrine cells (neuroendocrine group).

METHODS

We analyzed a single-cell RNA sequencing dataset from the normal human thymus. Concurrently, we examined publicly available datasets on the mRNA expression and methylation status of TECs and lung cancers. Real-time quantitative PCR was also conducted with our tissue samples.

RESULTS

Thymic carcinomas displayed a neuroendocrine phenotype biased toward tuft cells and ionocytes. When exploring the possible regulators of this phenotype, we discovered that HDAC9 and NFATC1 were characteristically expressed in the neuroendocrine group in adult TECs and thymic carcinomas. Additionally, the pan-thymic epithelium markers, exemplified by PAX9 and SIX1, were significantly suppressed in thymic carcinomas.

CONCLUSIONS

Thymic carcinomas might be characterized by unique neuroendocrine differentiation and loss of identity as thymic epithelial cells. Future studies investigating the role of HDAC9 and NFATC1 in thymic epithelium are warranted to explore their potential as therapeutic targets in TETs.

The deubiquitinase UCHL1 negatively controls osteoclastogenesis by regulating TAZ/NFATC1 signalling

The ubiquitin‒proteasome system (UPS) plays a key role in maintaining protein homeostasis and bone remodelling. However, the role of deubiquitinating enzymes (DUBs) in bone resorption is still not well defined. Here, we identified the deubiquitinase ubiquitin C-terminal hydrolase 1 (UCHL1) as a negative regulator of osteoclastogenesis by using the GEO database, proteomic analysis, and RNAi. Osteoclast-specific UCHL1 conditional knockout mice exhibited a severe osteoporosis phenotype in an ovariectomized model. Mechanistically, UCHL1 deubiquitinated and stabilized the transcriptional coactivator with PDZ-binding motif (TAZ) at the K46 residue, thereby inhibiting osteoclastogenesis. The TAZ protein underwent K48-linked polyubiquitination, which was degraded by UCHL1. As a substrate of UCHL1, TAZ regulates NFATC1 through a nontranscriptional coactivator function by competing with calcineurin A (CNA) for binding to NFATC1, which inhibits NFATC1 dephosphorylation and nuclear transport to impede osteoclastogenesis. Moreover, overexpression of UCHL1 locally alleviated acute and chronic bone loss. These findings suggest that activating UCHL1 may serve as a novel therapeutic approach targeting bone loss in various bone pathological states.

NFATC1 and NFATC2 expression patterns in human osteochondromas

Background

Our previous study in genetic mouse models found that NFATc1 and NFATc2 suppress osteochondroma formation from entheseal progenitors. However, it remains unclear whether NFAT signaling is also involved in human osteochondromagenesis. As the first step in addressing this question, the current study aimed to determine the expression patterns of NFATC1 and NFATC2 in human osteochondroma samples.

Methods

Immunohistochemistry (IHC) was used to examine and analyze NFATC1 and NFATC2 expression in human osteochondroma samples. The human periosteum was used to map the expression of NFATC1 under physiological conditions by IHC. Furthermore, human periosteal progenitors were isolated and identified from the periosteal tissues of bone fracture healing patients. The expression of NFATC1 in human periosteal progenitors was characterized by Western blotting compared to human bone marrow stromal cells (BMSC).

Results

The IHC results showed that the expression of NFATC1 was undetectable in most human osteochondromas cells, and only a small proportion of osteochondroma cells, especially clonally grown chondrocytes, showed positive staining of NFATC1. NFATC2 expression was also undetectable in most chondrocytes in human osteochondromas. The mouse and human periosteum showed a comparable ratio of NFATC1 positive cells (9.56 ± 0.80% vs 11.04 ± 2.05%, P = 0.3101). Furthermore, Western blotting analysis revealed that NFATC1 expression was highly enriched in human periosteal progenitors compared to BMSC.

Conclusions

NFATC1 and NFATC2 are undetectable in most human osteochondroma chondrocytes. The expression pattern of NFATC1 in human osteochondromas and the normal periosteum suggests that NFAT signaling could be suppressed during human osteochondromagenesis.

Correlation of the transcription factors IRF4 and BACH2 with the abnormal NFATC1 expression in T cells from chronic myeloid leukemia patients

OBJECTIVE

T cell dysfunction is a common characteristic of patients with myeloid leukemia and is closely related to clinical efficacy and prognosis. In order to clarify the mechanisms leading to the T cell dysfunction, we characterized the gene expression profile of T cells from chronic myelogenous leukemia (CML) patients by microarray analysis and investigated the related regulating pathway.

METHODS

We employed gene expression profiling, bioinformatics and real-time quantitative reverse transcription PCR (RT-qPCR) to detect genes differentially expressed in CML patients versus healthy donors.

RESULTS

There were 1704 genes differentially expressed between CD3⁺ T cells from CML patients and healthy donors, including 868 up-regulated genes and 836 down-regulated genes, which mostly related to T cell functional pathways. In particular, lower expression of NFATC1, a member of the TCR signaling pathway, was detected in CD3⁺ T cells from CML patients. We further found that the expression of IRF4 and BACH2, transcription factors that potentially regulate NFATC1, in CD3⁺ T cells from CML patients was significantly lower than that in healthy donors.

CONCLUSION

We for the first time observed the altered gene expression profiles of CD3⁺ T cells from CML patients, and the results suggested that IRF4, BACH2 and NFATC1 may be involved in regulating T cell dysfunction in CML patients in the form of a transcriptional regulatory network. These findings may provide potential targets for tyrosine kinase inhibitors in combination with other targeted immunotherapies .

DNA methylation of Nuclear Factor of Activated T Cells 1 mediates the prospective relation between exposure to different traumatic event types and post-traumatic stress disorder

The mechanisms through which exposure to differing trauma types become biologically embedded to shape the risk for post-traumatic stress disorder (PTSD) is unclear. DNA methylation (5-mC), particularly in stress-relevant genes, may play a role in this relationship. Here, we conducted path analysis using generalized structural equation modeling to investigate whether blood-derived 5-mC in Nuclear Factor of Activated T Cells 1 (NFATC1) mediates the prospective association between each of five different trauma types ("assaultive violence", "other injury or shocking experience", "learning of trauma to loved one", "sudden, unexpected death of a close friend or relative", and "other") and lifetime PTSD. All five trauma types were significantly associated with reduced methylation at NFATC1 CpG site, cg17057218. Two of the five trauma types were significantly associated with increased methylation at NFATC1 CpG site, cg22324981. Moreover, methylation at cg17057218 significantly mediated 21-32% of the total effect for four of the five trauma types, while methylation at cg22324981 mediated 27-40% of the total effect for two of the five trauma types. These CpG sites were differentially associated with transcription factor binding sites and chromatin state signatures. NFATC1 5-mC may be a potential mechanism in the relationship between some trauma types and prospective risk for PTSD.

SREBP2 promotes the viability, proliferation, and migration and inhibits apoptosis in TGF-β1-induced airway smooth muscle cells by regulating TLR2/NF-κB/NFATc1/ABCA1 regulatory network

Asthma is a respiratory disease with complex pathogenesis. Sterol-responsive element-binding proteins 2 (SREBP2) was found to bind to promoter sequences of ABCA1 to suppress ABCA1 promoter activity. This study aimed to explore the expression level of SREBP2 and ATP-binding cassette transporter A1 (ABCA1), and their effects on the development of airway smooth muscle cells (ASMCs) in asthma. ASMCs were treated with different concentrations of TGF-β1 (0, 0.5, 1, 5 and 10 ng/mL). Short hairpin SREBP2 (shSREBP2), SREBP2, shABCA1 or ABCA1 were transfected into ASMCs. Cell viability, proliferation, apoptosis, migration, and the expression of SREBP2, ABCA1 and related pathway proteins were detected by MTT assay, Brdu staining, flow cytometer, Transwell assay, qRT-PCR, and Western blotting, respectively. The results showed that TGF-β1 increased the viability, proliferation, migration and inhibited apoptosis in ASMCs. Moreover, TGF-β1 also decreased the expression of ABCA1, cleaved caspase-3, cleaved PARP, E-cadherin, and increased the expression of vimentin, TLR2, p-p65 and NFATc1. SREBP2 knockdown alleviated these TGF-β1-induced changes. SREBP2 overexpression inhibited ABCA1 expression and apoptosis, and promoted cell migration and the expression of TLR2, p-p65, NFATc1 in ASMCs. ABCA1 overexpression alleviated these SREBP2-induced promoting and inhibition effects. In conclusion, SREBP2 activates TLR2/NF-κB/NFATc1 regulatory network and promotes TGF-β1-induced cell movement through inhibiting ABCA1 expression.

Genetic and functional analyses detect one pathological NFATC1 mutation in a Chinese tricuspid atresia family

Background

Cardiac valvulogenesis is a highly conserved process among vertebrates and cause unidirectional flow of blood in the heart. It was precisely regulated by signal pathways such as VEGF, NOTCH, and WNT and transcriptional factors such as TWIST1, TBX20, NFATC1, and SOX9. Tricuspid atresia refers to morphological deficiency of the valve and confined right atrioventricular traffic due to tricuspid maldevelopment, and is one of the most common types of congenital valve defects.

Methods

We recruited a healthy couple with two fetuses aborted due to tricuspid atresia and identified related gene mutations using whole‐exome sequencing. We then discussed the pathogenic significance of this mutation by bioinformatic and functional analyses.

Results

PROVEAN, PolyPhen, MutationTaster, and HOPE indicated the mutation could change the protein function and cause disease; Western blotting showed the expression of NFATC1 c.964G>A mutation was lower than the wild type. What's more, dual‐luciferase reporter assay showed the transcriptional activity of NFATC1 was impact by mutation and the expression of downstream DEGS1 was influenced.

Conclusion

Taken together, the c.964G>A mutation might be pathological and related to the occurrence of disease. Our research tended to deepen the understanding of etiology of tricuspid atresia and gene function of NFATC1, and provide some references or suggestions for genetic diagnosis of tricuspid atresia.

Magnesium favors the capacity of vitamin D3 to induce the monocyte differentiation of U937 cells

The hematopoietic U937 cells are able to differentiate into monocytes, macrophages, or osteoclasts when stimulated, respectively, with vitamin D3 (VD3), phorbol 12-myristate 13-acetate (PMA) or PMA plus VD3. We have previously demonstrated that magnesium (Mg) strongly potentiates the osteoclastic differentiation of U937 cells. In this study, we investigated whether such an effect may be ascribed to a capacity of Mg to modulate the monocyte differentiation of U937 cells and/or to an ability of Mg and VD3 to act directly and independently on the early phases of the osteoclastic differentiation. To address this issue, we subjected U937 cells to an individual and combined treatment with Mg and VD3 and then we analyzed, by flow cytometry and quantitative real-time polymerase chain reaction, the expression of a number of genes related to the early phases of the differentiation pathways under consideration. The results obtained indicated that Mg favors the monocyte differentiation of U937 cells induced by VD3 and at the same time, Mg contrasts the inhibitory effect that VD3 exerts on the osteoclastic differentiation in the absence of PMA. The crucial and articulated role played by Mg in diverse pathways of the osteoclastic differentiation of U973 cells is emphasized.

A unique epithelioid vascular neoplasm of bone characterized by EWSR1/FUS-NFATC1/2 fusions

An increasing number of epithelioid vascular lesions, in particular tumors from the benign and low-grade end of the spectrum, have been characterized by recurrent gene fusions. As a result, the detection of these molecular markers have improved the classification of diagnostically challenging cases. However, despite the significant progress, there are occasional lesions that do not fit in known histologic or molecular groups. Herein, we present five such unclassified epithelioid vascular lesions, which occurred in the bone and showed a distinct morphology composed of alternating vasoformative and solid growth and mild to moderate nuclear pleomorphism. The variegated morphologic appearance resembled that of composite hemangioendothelioma, being distinct from both epithelioid hemangioma and epithelioid hemangioendothelioma, and consistently showed cytologic atypia. Due to their unusual morphologic appearance and negative molecular work-up, targeted transcriptome sequencing was performed in two cases showing the presence of NFATC2 fusions with either EWSR1 or FUS genes. Three additional bone tumors with EWSR1 gene rearrangements were identified by FISH screening of a large cohort of 45 fusion-negative epithelioid vascular neoplasms, one fused to NFATC2 while two others to NFATC1. There were three females and two males, with a wide age range at presentation, mean of 44 years. The lesions occurred in the pelvis, maxillary sinus, and humerus. Two patients presented with polyostotic disease, both located in the pelvic bones. Two patients had available follow-up, one developed two local recurrences in the humerus over a 15-year period, while the other showed no recurrence 4 years subsequent to an en-bloc resection. Tumors were positive for CD31 and ERG, while negative for EMA, CK, synaptophysin, and chromogranin. FISH confirmed this abnormality in all cases, none of them being associated with gene amplifications. Further studies are needed to establish the pathogenetic relationship of this rare molecular subset with other epithelioid vascular tumors and to determine its clinical behavior.

Angiotensin II upregulates RANKL/NFATC1 expression in synovial cells from patients with rheumatoid arthritis through the ERK1/2 and JNK pathways

Background

Angiotensin II (Ang II) is associated with rheumatoid arthritis (RA) development. The present study investigated the impact of Ang II on the expression of receptor activator of nuclear factor-κB ligand (RANKL), as well as of nuclear factor of activated T cells cytoplasmic 1 (NFATC1) in RA synovial cells, and explored the underlying mechanism.

Methods

The expression levels of RANKL, NFATC1, and Ang II type 1 receptor (AT1R) were analyzed by RT PCR, western-blot, and/or immunohistochemistry. Western blot was also used to analyze the p38MAPK, JNK, and ERK1/2 pathways.

Results

The expressions of RANKL and NFATC1 increased in synovial tissues of RA compared to osteoarthritis (OA) synovial tissues. The expression of RANKL was upregulated by Ang II, and this effect was mitigated by an AT1R blocker but not by an AT2R blocker. Furthermore, Ang II activated the ERK1/2, JNK, and p38MAPK pathways, and this effect was blocked by the AT1R blocker. However, ERK1/2 and JNK inhibitors, but not a p38MAPK inhibitor, blocked Ang II-induced RANKL expression. Ang II also increased the level of NFATC1, and this upregulation was attenuated by AT1R blockade, ERK1/2 and JNK inhibition, and siRNA-mediated RANKL silencing, but not by AT2R blockade or p38MAPK inhibition.

Conclusion

Our results indicated that Ang II activated the ERK1/2 and JNK pathways via AT1R, thus upregulating RANKL and NFATC1 expressions in RA synovial cells.

Do We Use Methylation of NFATC1 and FOS Genes As a Biomarker for Postmenopausal Osteoporosis?

Genetic and epigenetic factors have an important role during the development of osteoporosis. Receptor activator of nuclear factor-κ B (NF-κB) (RANK)/receptor activator of NF-κB ligand (RANKL) pathway is important for the bone remodeling, and NFATC1 and FOS are the downtargets of this pathway. Here, we report methylation status of NFATC1 and FOS genes in post- and premenopausal women. In this study, 30 premenopausal and 35 postmenopausal women were included. Methylation sensitive-high resolution melting (MS-HRM) analysis was used for identification of NFATC1 and FOS genes methylation. The NFATC1 gene was methylated in 11 of the 35 postmenopausal women, and the FOS gene was methylated in six of the postmenopausal women (p >0.005). Here, we found statistically significant association between unmethylation of the NFATC1 gene and postmenopausal status. This result explains the epigenetic regulation of osteoclasts during the menopausal transition, and for the first time, our results can be used for epigenetic explanation of postmenopausal osteoporosis in the literature. However, the limited number of studies in this field makes our results crucial. Our results showed great value of epigenetic profiles of postmenopausal women.

PIP5k1β controls bone homeostasis through modulating both osteoclast and osteoblast differentiation

PIP5k1β is crucial to the generation of phosphotidylinosotol (4, 5)P2. PIP5k1β participates in numerous cellular activities, such as B cell and platelet activation, cell phagocytosis and endocytosis, cell apoptosis, and cytoskeletal organization. In the present work, we aimed to examine the function of PIP5k1β in osteoclastogenesis and osteogenesis to provide promising strategies for osteoporosis prevention and treatment. We discovered that PIP5k1β deletion in mice resulted in obvious bone loss and that PIP5k1β was highly expressed during both osteoclast and osteoblast differentiation. Deletion of the gene was found to enhance the proliferation and migration of bone marrow-derived macrophage-like cells to promote osteoclast differentiation. PIP5k1β-/- osteoclasts exhibited normal cytoskeleton architecture but stronger resorption activity. PIP5k1β deficiency also promoted activation of mitogen-activated kinase and Akt signaling, enhanced TRAF6 and c-Fos expression, facilitated the expression and nuclear translocation of NFATC1, and upregulated Grb2 expression, thereby accelerating osteoclast differentiation and function. Finally, PIP5k1β enhanced osteoblast differentiation by upregulating master gene expression through triggering smad1/5/8 signaling. Therefore, PIP5k1β modulates bone homeostasis and remodeling.

Detection of de novo del(18)(q22.2) and a familial of 15q13.2-q13.3 microduplication in a fetus with congenital heart defects

OBJECTIVE

We present detection of de novo del(18)(q22.2) and a familial 15q13.2-q13.3 microduplication in a fetus with congenital heart defects (CHD).

CASE REPORT

A 27-year-old, primigravid woman was referred for genetic counseling because of fetal CHD. Prenatal ultrasound at 17 weeks of gestation revealed pericardial effusion, cardiomegaly and a large ventricular septal defect. The pregnancy was subsequently terminated at 18 weeks of gestation, and a 192-g female fetus was delivered with facial dysmorphism. Cytogenetic analysis of the umbilical cord revealed a karyotype of 46,XX,del(18)(q22.2). The parental karyotypes were normal. Array comparative genomic hybridization (aCGH) of the placental tissue revealed a 2.08-Mb 15q13.2-q13.3 microduplication encompassing KLF13 and CHRNA7, and a 10.74-Mb 18q22.2-q23 deletion encompassing NFATC1. The phenotypically normal father carried the same 2.08-Mb 15q13.2-q13.3 microduplication. Polymorphic DNA marker analysis confirmed a paternal origin of the distal 18q deletion.

CONCLUSION

Prenatal diagnosis of CHD should include a complete genetic study of the embryonic tissues, and the acquired information is useful for genetic counseling.

An intronic polymorphism of NFATC1 gene shows a risk association with biopsy-proven acute rejection in renal transplant recipients

Background

We aimed to explore the influence of single nucleotide polymorphisms (SNPs) in NFATC1 gene on the occurrence of biopsy-proven acute rejection (BPAR) in renal transplant recipients.

Methods

Blood samples from 131 subjects with stable allograft function (STA) and 69 with BPAR episodes were collected and analyzed using target sequencing (TS) with an established panel. Odds ratios (OR) and 95% confidence intervals (95% CIs) were calculated for logistic regression models adjusted for confounding factors. Pathological changes were extracted and the relationship with tagger SNPs was calculated. Moreover, the CCK-8 assay was performed to explore the proliferation of T lymphocytes, and PCR, Western blotting and enzyme-linked immunosorbent assay were applied to identify the effect of mutant on the activation of T cells.

Results

High-quality readouts were obtained for 55 NFATC1 SNPs and 14 tagger SNPs were remained for further analysis. After adjusting for clinical confounding factors, the distribution of four NFATC1 SNPs, including rs2290154, rs2304738, rs754093 and rs754096, were statistically significant between STA and BPAR groups. Pathological association analysis indicated one SNP, rs2290154, was significantly related with the Banff score and renal tubulitis. Our in vitro study suggested that NFATC1 rs2290154 mutant could remarkably promote the T cell proliferation, increase the transcription of NFATC1 mRNA and expression of NFATC1 protein, as well as the interleukin-2 (IL-2) secretion.

Conclusions

We reported the crucial association of NFATC1 gene with the occurrence of acute rejection (AR) episodes. Moreover, in vitro NFATC1 rs2290154 was significantly involved in the T lymphocytes activation and proliferation through increasing the translation of NFATC1 mRNA and expression of NFATC1 protein, along with the secretion of IL-2.

Phosphorylation of NFATC1 at PIM1 target sites is essential for its ability to promote prostate cancer cell migration and invasion

Background

Progression of prostate cancer from benign local tumors to metastatic carcinomas is a multistep process. Here we have investigated the signaling pathways that support migration and invasion of prostate cancer cells, focusing on the role of the NFATC1 transcription factor and its post-translational modifications. We have previously identified NFATC1 as a substrate for the PIM1 kinase and shown that PIM1-dependent phosphorylation increases NFATC1 activity without affecting its subcellular localization. Both PIM kinases and NFATC1 have been reported to promote cancer cell migration, invasion and angiogenesis, but it has remained unclear whether the effects of NFATC1 are phosphorylation-dependent and which downstream targets are involved.

Methods

We used mass spectrometry to identify PIM1 phosphorylation target sites in NFATC1, and analysed their functional roles in three prostate cancer cell lines by comparing phosphodeficient mutants to wild-type NFATC1. We used luciferase assays to determine effects of phosphorylation on NFAT-dependent transcriptional activity, and migration and invasion assays to evaluate effects on cell motility. We also performed a microarray analysis to identify novel PIM1/NFATC1 targets, and validated one of them with both cellular expression analyses and in silico in clinical prostate cancer data sets.

Results

Here we have identified ten PIM1 target sites in NFATC1 and found that prevention of their phosphorylation significantly decreases the transcriptional activity as well as the pro-migratory and pro-invasive effects of NFATC1 in prostate cancer cells. We observed that also PIM2 and PIM3 can phosphorylate NFATC1, and identified several novel putative PIM1/NFATC1 target genes. These include the ITGA5 integrin, which is differentially expressed in the presence of wild-type versus phosphorylation-deficient NFATC1, and which is coexpressed with PIM1 and NFATC1 in clinical prostate cancer specimens.

Conclusions

Based on our data, phosphorylation of PIM1 target sites stimulates NFATC1 activity and enhances its ability to promote prostate cancer cell migration and invasion. Therefore, inhibition of the interplay between PIM kinases and NFATC1 may have therapeutic implications for patients with metastatic forms of cancer.

Graphical abstract

Nuclear factor of activated T-cells, NFATC1, governs FLT3ITD-driven hematopoietic stem cell transformation and a poor prognosis in AML

Background

Acute myeloid leukemia (AML) patients with a high allelic burden of an internal tandem duplication (ITD)-mutated FMS-like Tyrosine Kinase-3 (FLT3) have a dismal outcome. FLT3^ITD triggers the proliferation of the quiescent hematopoietic stem cell (HSC) pool but fails to directly transform HSCs. While the inflammatory transcription factor nuclear factor of activated T-cells 2 (NFAT2, NFATC1) is overexpressed in AML, it is unknown whether it plays a role in FLT3^ITD-induced HSC transformation.

Methods

We generated a triple transgenic mouse model, in which tamoxifen-inducible Cre-recombinase targets expression of a constitutively nuclear transcription factor NFATC1 to FLT3^ITD positive HSC. Emerging genotypes were phenotypically, biochemically, and also transcriptionally characterized using RNA sequencing. We also retrospectively analyzed the overall survival of AML patients with different NFATC1 expression status.

Results

We find that NFATC1 governs FLT3^ITD-driven precursor cell expansion and transformation, causing a fully penetrant lethal AML. FLT3^ITD/NFATC1-AML is re-transplantable in secondary recipients and shows primary resistance to the FLT3^ITD-kinase inhibitor quizartinib. Mechanistically, NFATC1 rewires FLT3^ITD-dependent signaling output in HSC, involving augmented K-RAS signaling and a selective de novo recruitment of key HSC-transforming signaling pathways such as the Hedgehog- and WNT/B-Catenin signaling pathways. In human AML, NFATC1 overexpression is associated with poor overall survival.

Conclusions

NFATC1 expression causes FLT3^ITD-induced transcriptome changes, which are associated with HSC transformation, quizartinib resistance, and a poor prognosis in AML.

Electronic supplementary material

The online version of this article (10.1186/s13045-019-0765-y) contains supplementary material, which is available to authorized users.

Combined low-dose LiCl and LY294002 for the treatment of osteoporosis in ovariectomized rats

BACKGROUND

To provide a low-toxicity and high-efficacy clinical treatment for osteoporosis via a novel combination of LiCl and LY294002.

METHODS

The protein levels of p-AKT, AKT, p-GSK3β, GSK3β, β-catenin, p-β-catenin, and NFATC1 were measured in osteoblasts and osteoclasts by Western blot. ALP activity and TRACP activity were measured using the corresponding kit. The levels of BALP, PINP, CTX, and TRACP-5b were determined in accordance with the requirements of the ELISA kits. Microstructural analysis was performed on the left distal femur using microcomputed tomography.

RESULTS

Treatment with the combination of LiCl and LY294002 led to a markedly increased osteoblast activity but significantly decreased osteoclast differentiation and bone absorption capacity compared with the treatment with LiCl or LY294002 alone (P < 0.01). In serum, the low-dose combination of LiCl and LY294002 significantly enhanced BALP levels (P < 0.01) and significantly decreased PINP, TRACP-5b, and CTX levels (P < 0.01) compared with the application of either drug alone.

CONCLUSIONS

This study indicates that drug combinations directed at multiple targets could be used for osteoporosis treatment by promoting osteoblast proliferation and inhibiting differentiation with high efficiency.

Cooperation of PU.1 With IRF8 and NFATc1 Defines Chromatin Landscapes During RANKL-Induced Osteoclastogenesis

Receptor activator of nuclear factor κB ligand (RANKL) induces osteoclast (OC) differentiation from bone marrow-derived macrophages (BMMs). The transcription factors nuclear factor of activated T cells 1 (NFATc1) and interferon regulatory factor (IRF) 8 play positive and negative roles, respectively, in this process. However, genomewide mapping of the active cis-regulatory elements regulating OC differentiation has not been performed, and little is known about the global landscape of OC-specific gene regulation. We used chromatin immunoprecipitation and formaldehyde-assisted isolation of regulatory elements followed by sequencing to show that PU.1 transcription factor binding motifs were overrepresented at active cis-regulatory regions in both murine BMMs and OCs, while IRF and NFAT binding motifs were selectively enriched at these regions in BMMs and OCs, respectively. We also found that RANKL induced the downregulation of Irf8 and upregulation of Nfatc1 expression, which was associated with dramatic alterations in histone modification. BMM-specific PU.1 binding sites were observed to overlap with IRF8 binding sites in BMMs, and this also occurred for OC-specific PU.1 binding sites and NFATc1 binding sites in OCs. The expression of genes with IRF8 peaks within BMM-specific PU.1 binding sites was significantly higher in BMMs than in OCs, while that of genes with NFATc1 peaks within OC-specific PU.1 binding sites was significantly higher in OCs than in BMMs. Our results suggest that PU.1 switches its transcription partner from IRF8 to NFATc1 and alters the binding regions during RANKL-induced osteoclastogenesis, which is associated with changes in epigenetic profiles and the control of cell type-specific gene expression. © 2019 American Society for Bone and Mineral Research.

FUN14 domain-containing 1 promotes breast cancer proliferation and migration by activating calcium-NFATC1-BMI1 axis

BACKGROUND

FUN14 domain-containing 1 (FUNDC1), as a novel member of mitochondria-associated endoplasmic reticulum (ER) membranes associates with mitochondrial division and mitophagy. However, the expression profile and functional roles of FUNDC1 remain largely unclear in human cancer biology, including breast cancer (BC).

METHODS

Immunohistochemistry and western blot analysis were used to determine the expression of FUNDC1 and BMI1 polycomb ring finger oncogene (BMI1). CCK8, cell counting and transwell assays were used to analyze cell proliferation, migration and invasion, respectively. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were used to detect the transcriptional regulation of Nuclear factor of activated T-cells, cytoplasmic 1 (NFATC1). The prognostic merit of NFATC1 expression was assessed by Kaplan-Meier assay.

FINDINGS

Immunohistochemistry revealed strong immunostaining for FUNDC1 in cytoplasmic and nuclear membrane distribution in BC tissues as compared with normal breast epithelium. Kaplan-Meier survival analysis showed worse outcome for BC patients with high FUNDC1 expression. In vitro assay of gain- and loss-of-function of FUNDC1 suggested that FUNDC1 could stimulate BC cell proliferation, migration and invasion. Furthermore, elevated FUNDC1 level promoted Ca²⁺ cytosol influx from ER and extracellular, as well as NFATC1 nuclear translocation and activity. Nuclear NFATC1 bound to the BMI1 gene promoter and transcriptionally upregulated its expression. Notably, BMI1 overexpression could rescue the loss of function of FUNDC1. Co-expression of FUNDC1 and BMI1 in BC patients predicted worse prognosis than without either expression.

INTERPRETATION

FUNDC1 might promote BC progression by activating the Ca²⁺-NFATC1-BMI1 axis. This pathway may be promising for developing multiple targets for BC therapy.

Interleukin 29 inhibits RANKL-induced osteoclastogenesis via activation of JNK and STAT, and inhibition of NF-κB and NFATc1

Interleukin (IL)-29 is known to modulate immune functions of monocytes or macrophages. In this study, we investigated the effect and its underlying mechanism of IL-29 on receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclastogenesis using murine macrophage cell line RAW264.7 cells and bone-marrow-derived monocyte/macrophage precursor cells (BMMs), and human peripheral blood mononuclear cells (PBMCs). In response to human recombinant IL-29, cell viability and apoptosis were assessed by Cell Counting Kit-8 and flow cytometry; the osteoclast formation and activity by tartrate-resistant acid phosphatase (TRAP) staining and pit formation assay, respectively; the expression and activation of molecules that associated with osteoclastogenesis by real time-PCR, immunoblotting or immunofluorescent analysis. IL-28 receptor α (IL-28Rα), a specific receptor of IL-29 was expressed on RAW264.7 cells. Although IL-29 did not affect the viability and apoptosis of RAW264.7 cells, it inhibited multinucleated cells in the differentiation of osteoclastogenesis, the bone-resorbing activity of mature osteoclasts and osteoclastic specific genes expression including TRAP, cathepsin K (CTSK), nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), C-Fos and matrix metallopeptidase 9 (MMP-9). This inhibitory effect of IL-29 was confirmed on BMMs and PBMCs and mediated via IL-28Rα through the activation of Stat1 and 3 and the suppression of nuclear factor kappa B (NF-κB) and NFATc1 nuclear translocation in RAW264.7 cells. In conclusion, IL-29 inhibited osteoclastogenesis via activation of STAT signaling pathway, prevention of NF-κB activation and NFATc1 translocation, and suppression of downstream osteoclastogenic genes expression.

Degenerated hair follicle cells and partial loss of sebaceous and eccrine glands in a familial case of axenfeld-rieger syndrome: An emerging role for the FOXC1/NFATC1 genetic axis

BACKGROUND

Cutaneous malformations are at times associated with some forms of congenital heart defects. Many a times subtle cutaneous phenotypes maybe overlooked as their significance on the lives of individuals is minimal. Lebanon represents an area of high consanguinity, where the rates can go beyond 70% in some districts. For the past 6 years, we have been studying several genodermatoses in Lebanon including those with cardiac malformations.

OBJECTIVES

The main aim of this study is to document the genetic basis of a familial case of Axenfeld-Rieger Syndrome (ARS) with a mild cutaneous phenotype represented histologically with degeneration/ absence of hair follicles and incomplete formation of sebaceous and eccrine glands, in addition to the cardiac and ocular phenotypes.

METHODS

Whole exome sequencing was performed on two identical-twins with ARS along with their affected father and non-affected mother. Sanger sequencing was used to confirm the mutation, and the effects of the mutations on protein function was assessed in vitro using transient transfections.

RESULTS

A novel mutation inFOXC1 designated p.L240Rfs*75 was found in both twins and their father. The affected individuals share also a rare documented variant in NFATC1 designated p.V197 M. Both were absent from 200 Lebanese exomes. Our in vitro results suggested a gain of function activity of the FOXC1/NFATC1 complex, confirming its documented role in controlling murine hair follicle stem cells quiescence and regeneration.

CONCLUSION

This is the first documented human case with a mutation inFOXC1 regulating multi-organ developmental pathways that reflect a conserved mechanism in cell differentiation and proliferation.

Heterozygous missense mutations in NFATC1 are associated with atrioventricular septal defect

Atrioventricular septal defect (AVSD) may occur as part of a complex disorder (e.g., Down syndrome, heterotaxy), or as isolate cardiac defect. Multiple lines of evidence support a role of calcineurin/NFAT signaling in AVSD, and mutations in CRELD1, a protein functioning as a regulator of calcineurin/NFAT signaling have been reported in a small fraction of affected subjects. In this study, 22 patients with isolated AVSD and 38 with AVSD and heterotaxy were screened for NFATC1 gene mutations. Sequence analysis identified three missense variants in three individuals, including a subject with isolated AVSD [p.(Ala367Val)], an individual with AVSD and heterotaxy [p.(Val210Met)], and a subject with AVSD, heterotaxy, and oculo-auriculo-vertebral spectrum (OAVS) [p.(Ala696Thr)], respectively. The latter was also heterozygous for a missense change in TBX1 [p.(Pro86Leu)]. Targeted resequencing of genes associated with AVSD, heterotaxy, or OAVS excluded additional hits in the three mutation-positive subjects. Functional characterization of NFATC1 mutants documented defective nuclear translocation and decreased transcriptional transactivation activity. When expressed in zebrafish, the three NFATC1 mutants caused cardiac looping defects and altered atrioventricular canal patterning, providing evidence of their functional relevance in vivo. Our findings support a role of defective NFATC1 function in the etiology of isolated and heterotaxy-related AVSD.

NFATC1 activation by DNA hypomethylation in chronic lymphocytic leukemia correlates with clinical staging and can be inhibited by ibrutinib

B cell receptor (BCR) signaling is a key for survival of chronic lymphocytic leukemia (CLL) cells, and BCR signaling inhibitors are clinically active. However, relapse and resistance to treatment require novel treatment options. To detect novel candidate therapeutic targets, we performed a genome-wide DNA methylation screen with custom arrays and identified aberrant promoter DNA methylation in 2,192 genes. The transcription factor NFATC1 that is a downstream effector of BCR signaling was among the top hypomethylated genes and was concomitantly transcriptionally upregulated in CLL. Intriguingly, NFATC1 promoter DNA hypomethylation levels were significantly variant in clinical trial cohorts from different disease progression stages and furthermore correlated with Binet disease staging and thymidine kinase levels, strongly suggesting a central role of NFATC1 in CLL development. Functionally, DNA hypomethylation at NFATC1 promoter inversely correlated with RNA levels of NFATC1 and dysregulation correlated with expression of target genes BCL-2, CCND1 and CCR7. The inhibition of the NFAT regulator calcineurin with tacrolimus and cyclosporin A and the BCR signaling inhibitor ibrutinib significantly reduced NFAT activity in leukemic cell lines, and NFAT inhibition resulted in increased apoptosis of primary CLL cells. In summary, our results indicate that the aberrant activation of NFATC1 by DNA hypomethylation and BCR signaling plays a major role in the pathomechanism of CLL.

mTORC1 Inhibits NF-κB/NFATc1 Signaling and Prevents Osteoclast Precursor Differentiation, In Vitro and In Mice

The mechanistic target of rapamycin complex 1 (mTORC1) is a critical sensor for bone homeostasis and bone formation; however, the role of mTORC1 in osteoclast development and the underlying mechanisms have not yet been fully established. Here, we found that mTORC1 activity declined during osteoclast precursors differentiation in vitro and in vivo. We further targeted deletion of Raptor (mTORC1 key component) or Tsc1 (mTORC1 negative regulator) to constitutively inhibit or activate mTORC1 in osteoclast precursors (monocytes/macrophages), using LyzM-cre mice. Osteoclastic formation was drastically increased in cultures of Raptor deficient bone marrow monocytes/macrophages (BMMs), and Raptor-deficient mice displayed osteopenia with enhanced osteoclastogenesis. Conversely, BMMs lacking Tsc1 exhibited a severe defect in osteoclast-like differentiation and absorptive function, both of which were restored following rapamycin treatment. Importantly, expression of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and nuclear factor of activated T cells, cytoplasmic 1 (NFATc1), transcription factors that are essential for osteoclast differentiation was negatively regulated by mTORC1 in osteoclast lineages. These results provide evidence that mTORC1 plays as a critical role as an osteoclastic differentiation-limiting signal and suggest a potential drawback in treating bone loss-related diseases with mTOR inhibitors clinically. © 2017 American Society for Bone and Mineral Research.

NFATC1 genotypes affect acute rejection and long-term graft function in cyclosporine-treated renal transplant recipients

AIM

To investigate the effects of SNPs in the cyclophilin A/calcineurin/nuclear factor of activated T-cells (NFATs) pathway genes (PPIA, PPP3CB, PPP3R1, NFATC1 and NFATC2) on cyclosporine (CsA) efficacy in renal transplant recipients.

MATERIALS & METHODS

Seventy-six tag SNPs were detected in 155 CsA-treated renal recipients with at least a 5-year follow-up. The associations of SNPs with acute rejection, nephrotoxicity, pneumonia and estimated glomerular filtration rate post transplant were explored.

RESULTS

NFATC1 rs3894049 GC was a risk factor for acute rejection compared with CC carriers (p = 0.0005). NFATC1 rs2280055 TT carriers had a more stable estimated glomerular filtration rate level than CC (p = 0.0004).

CONCLUSION

Detecting NFATC1 polymorphisms could help predict CsA efficacy in renal transplant patients.

Circadian Clock Regulates Bone Resorption in Mice

The circadian clock controls many behavioral and physiological processes beyond daily rhythms. Circadian dysfunction increases the risk of cancer, obesity, and cardiovascular and metabolic diseases. Although clinical studies have shown that bone resorption is controlled by circadian rhythm, as indicated by diurnal variations in bone resorption, the molecular mechanism of circadian clock-dependent bone resorption remains unknown. To clarify the role of circadian rhythm in bone resorption, aryl hydrocarbon receptor nuclear translocator-like (Bmal1), a prototype circadian gene, was knocked out specifically in osteoclasts. Osteoclast-specific Bmal1-knockout mice showed a high bone mass phenotype due to reduced osteoclast differentiation. A cell-based assay revealed that BMAL1 upregulated nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1 (Nfatc1) transcription through its binding to an E-box element located on the Nfatc1 promoter in cooperation with circadian locomotor output cycles kaput (CLOCK), a heterodimer partner of BMAL1. Moreover, steroid receptor coactivator (SRC) family members were shown to interact with and upregulate BMAL1:CLOCK transcriptional activity. Collectively, these data suggest that bone resorption is controlled by osteoclastic BMAL1 through interactions with the SRC family and binding to the Nfatc1 promoter. © 2016 American Society for Bone and Mineral Research.

The calcineurin inhibitor tacrolimus as a new therapy in severe cherubism

Cherubism is a rare genetic disorder characterized by extensive growth of a bilateral granuloma of the jaws, resulting in facial disfigurement. Cherubism is caused by gain-of-function mutations in the SH3BP2 gene, leading to overactivation of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1)-dependent osteoclastogenesis. Recent findings in human and mouse cherubism have suggested that calcineurin inhibitors might be drug candidates in cherubism medical treatment. A 4-year-old boy with aggressive cherubism was treated with the calcineurin inhibitor tacrolimus for 1 year, and clinical, radiological, and molecular data were obtained. Immunohistologic analysis was performed to compare preoperative and postoperative NFATc1 staining and tartrate resistant acid phosphatase (TRAP) activity. Real-time PCR was performed to analyze the relative expression levels of OPG and RANKL. After tacrolimus therapy, the patient showed significant clinical improvement, including stabilization of jaw size and intraosseous osteogenesis. Immunohistologic analyses on granuloma showed that tacrolimus caused a significant reduction in the number of TRAP-positive osteoclasts and NFATc1 nuclear staining in multinucleated giant cells. Molecular analysis showed that tacrolimus treatment also resulted in increased OPG expression. We present the first case of effective medical therapy in cherubism. Tacrolimus enhanced bone formation by stimulating osteogenesis and inhibiting osteoclastogenesis.