Selectivity analysis of diaminopyrimidine-based inhibitors of MTHFD1, MTHFD2 and MTHFD2L.

The mitochondrial enzyme methylenetetrahydrofolate dehydrogenase (MTHFD2) is involved in purine and thymidine synthesis via 1C metabolism. MTHFD2 is exclusively overexpressed in cancer cells but absent in most healthy adult human tissues. However, the two close homologs of MTHFD2 known as MTHFD1 and MTHFD2L are expressed in healthy adult human tissues and share a great structural resemblance to MTHFD2 with 54% and 89% sequence similarity, respectively. It is therefore notably challenging to find selective inhibitors of MTHFD2 due to the structural similarity, in particular protein binding site similarity with MTHFD1 and MTHFD2L. Tricyclic coumarin-based compounds (substrate site binders) and xanthine derivatives (allosteric site binders) are the only selective inhibitors of MTHFD2 reported till date. Nanomolar potent diaminopyrimidine-based inhibitors of MTHFD2 have been reported recently, however, they also demonstrate significant inhibitory activities against MTHFD1 and MTHFD2L. In this study, we have employed extensive computational modeling involving molecular docking and molecular dynamics simulations in order to investigate the binding modes and key interactions of diaminopyrimidine-based inhibitors at the substrate binding sites of MTHFD1, MTHFD2 and MTHFD2L, and compare with the tricyclic coumarin-based selective MTHFD2 inhibitor. The outcomes of our study provide significant insights into desirable and undesirable structural elements for rational structure-based design of new and selective inhibitors of MTHFD2 against cancer.

Contribution of A1 to macrophage survival in cooperation with MCL-1 and BCL-XL in a murine cell model of myeloid differentiation.

Myeloid cells are the first line of defence against pathogens. Mitochondrial apoptosis signalling is a crucial regulator of myeloid cell lifespan and modulates the function of myeloid cells. The anti-apoptotic protein BCL-2-family protein BCL2A1/A1/BFL-1 is strongly upregulated in inflammation in macrophages. We analysed the contribution of A1 to apoptosis regulation in a conditional system of in vitro differentiation of murine macrophages from immortalised progenitors. We disabled the expression of A1 by targeting all murine A1 isoforms in the genome. Specific inhibitors were used to inactivate other anti-apoptotic proteins. Macrophage progenitor survival mainly depended on the anti-apoptotic proteins MCL-1, BCL-XL and A1 but not BCL-2. Deletion of A1 on its own had little effect on progenitor cell survival but was sensitised to cell death induction when BCL-XL or MCL-1 was neutralised. In progenitors, A1 was required for survival in the presence of the inflammatory stimulus LPS. Differentiated macrophages were resistant to inhibition of single anti-apoptotic proteins, but A1 was required to protect macrophages against inhibition of either BCL-XL or MCL-1; BCL-2 only had a minor role in these cells. Cell death by neutralisation of anti-apoptotic proteins completely depended on BAX with a small contribution of BAK only in progenitors in the presence of LPS. A1 and NOXA appeared to stabilise each other at the posttranscriptional level suggesting direct binding. Co-immunoprecipitation experiments showed the binding of A1 to NOXA and BIM. Interaction between A1 and Noxa may indirectly prevent neutralisation and destabilization of MCL-1. Our findings suggest a unique role for A1 as a modulator of survival in the macrophage lineage in concert with MCL-1 and BCL-XL, especially in a pro-inflammatory environment.

WTAP-mediated m6A modification of TRIM22 promotes diabetic nephropathy by inducing mitochondrial dysfunction via ubiquitination of OPA1.

OBJECTIVES: Diabetic nephropathy (DN) is one of the most serious microvascular complications of diabetes and is the most common cause of end-stage renal disease. Tripartite motif-containing (TRIM) proteins are a large family of E3 ubiquitin ligases that contribute to protein quality control by regulating the ubiquitin - proteasome system. However, the detailed mechanisms through which various TRIM proteins regulate downstream events have not yet been fully elucidated. The current research aimed to determine the function and mechanism of TRIM22 in DN. METHODS: DN models were established by inducing HK-2 cells using high glucose (HG) and diabetic mice (db/db mice). Cell viability, apoptosis, mitochondrial reactive oxygen species, and mitochondrial membrane potential were detected by Cell Counting Kit-8 and flow cytometry, respectively. Pathological changes were evaluated using hematoxylin and eosin, periodic acid schiff and Masson staining. The binding between TRIM22 and optic atrophy 1 (OPA1) was analyzed using co-immunoprecipitation. The m6A level of TRIM22 5'UTR was detected using RNA immunoprecipitation. RESULTS: TRIM22 was highly expressed in patients with DN. TRIM22 silencing inhibited HG-induced apoptosis and mitochondrial dysfunction in HK-2 cells. Promoting mitochondrial fusion alleviated TRIM22 overexpression-induced cell apoptosis, mitochondrial dysfunction in HK-2 cells, and kidney damage in mice. Mechanistically, TRIM22 interacted with OPA1 and induced its ubiquitination. Wilms tumor 1-associating protein (WTAP) promoted m6A modification of TRIM22 through the m6A reader insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1). DISCUSSION: TRIM22 silencing inhibited the progression of DN by interacting with OPA1 and inducing its ubiquitination. Furthermore, WTAP promoted m6A modification of TRIM22 via IGF2BP1.

p-STAT3-elevated E3 ubiquitin ligase DTX4 confers the stability of HBV cccDNA by ubiquitinating APOBEC3B in liver.

Background: Clinically, the persistence of HBV cccDNA is the major obstacle in anti-HBV therapy. However, the underlying mechanism of HBV cccDNA is poorly understood. The transcriptional factor STAT3 is able to activate HBV replication in liver. Approach & Results: RNA-Seq analysis demonstrated that cucurbitacin I targeting STAT3 was associated with virus replication in liver. HBV-infected human liver chimeric mouse model and HBV hydrodynamic injection mouse model were established. Then, we validated that cucurbitacin I effectively limited the stability of HBV cccDNA and HBV replication in cells, in which cucurbitacin I enhanced the sensitivity of pegylated interferon α (PEG-IFN α) against HBV via combination in vitro and in vivo. Mechanistically, we identified that cucurbitacin I increased the levels of APOBEC3B to control HBV cccDNA by inhibiting p-STAT3 in cells, resulting in the inhibition of HBV replication. Moreover, RNA-Seq data showed that E3 ubiquitin ligase DTX4 might be involved in the events. Then, we observed that HBV particles could upregulate DTX4 by increasing the levels of p-STAT3 in vitro and in vivo. The p-STAT3-elevated DTX4/male-specific lethal 2 (MSL2) independently and synergistically enhanced the stability of HBV cccDNA by facilitating the ubiquitination degradation of APOBEC3B in cells, leading to the HBV replication. Conclusions: p-STAT3-elevated DTX4 confers the stability of HBV cccDNA and HBV replication by facilitating the ubiquitination degradation of APOBEC3B. Cucurbitacin Ⅰ effectively enhances the sensitivity of PEG-IFN α in anti-HBV therapy by inhibiting the p-STAT3/DTX4/MSL2/APOBEC3B signalling. Our finding provides new insights into the mechanism of HBV cccDNA. The p-STAT3 and DTX4/MSL2 might serve as the therapeutical targets of HBV cccDNA.

APOBEC family reshapes the immune microenvironment and therapy sensitivity in clear cell renal cell carcinoma.

Emerging evidence suggests that the APOBEC family is implicated in multiple cancers and might be utilized as a new target for cancer detection and treatment. However, the dysregulation and clinical implication of the APOBEC family in clear cell renal cell cancer (ccRCC) remain elusive. TCGA multiomics data facilitated a comprehensive exploration of the APOBEC family across cancers, including ccRCC. Remodeling analysis classified ccRCC patients into two distinct subgroups: APOBEC family pattern cancer subtype 1 (APCS1) and subtype 2 (APCS2). The study investigated differences in clinical parameters, tumor immune microenvironment, therapeutic responsiveness, and genomic mutation landscapes between these subtypes. An APOBEC family-related risk model was developed and validated for predicting ccRCC patient prognosis, demonstrating good sensitivity and specificity. Finally, the overview of APOBEC3B function was investigated in multiple cancers and verified in clinical samples. APCS1 and APCS2 demonstrated considerably distinct clinical features and biological processes in ccRCC. APCS1, an aggressive subtype, has advanced clinical stage and a poor prognosis. APCS1 exhibited an oncogenic and metabolically active phenotype. APCS1 also exhibited a greater tumor mutation load and immunocompromised condition, resulting in immunological dysfunction and immune checkpoint treatment resistance. The genomic copy number variation of APCS1, including arm gain and loss, was much more than that of APCS2, which may help explain the tired immune system. Furthermore, the two subtypes have distinct drug sensitivity patterns in clinical specimens and matching cell lines. Finally, we developed a predictive risk model based on subtype biomarkers that performed well for ccRCC patients and validated the clinical impact of APOBEC3B. Aberrant APOBEC family expression patterns might modify the tumor immune microenvironment by increasing the genome mutation frequency, thus inducing an immune-exhausted phenotype. APOBEC family-based molecular subtypes could strengthen the understanding of ccRCC characterization and guide clinical treatment. Targeting APOBEC3B may be regarded as a new therapeutic target for ccRCC.

Increased autoreactivity and maturity of EBI2+ antibody-secreting cells from nasal polyps.

Elevated numbers of antibody-secreting cells (ASCs) and anti-double-stranded DNA (anti-dsDNA) antibodies are found in nasal polyp (NP) tissue. The presence of anti-dsDNA IgG in tissue prospectively predicts recurrent NP but the characteristics of the source ASCs are unknown. Here, we investigated whether NP B cells expressing the extrafollicular marker EBI2 have increased propensity for autoantibody production and evaluated the molecular characteristics of NP ASCs. NPs showed increased frequencies of anti-dsDNA IgG and total IgG ASCs compared with tonsils, with more pronounced differences among EBI2+ cells. In NPs, EBI2+ cells were frequently double negative (IgD-CD27-) and ASCs. Single-cell RNA-Seq analysis of tonsils and NPs revealed substantial differences in B lineage composition, including differences in percentages of ASCs, germinal centers, proliferative cells, and non-ASCs. NPs exhibited higher expression of specific isotypes (IGHE, IGHA1, IGHA2, and IGHG4) and mature plasma genes, including SDC1 and XBP1, than tonsils. Gene Ontology biological processes indicated upregulated NF-κB and downregulated apoptosis pathways in NP ASCs. Together, these data indicate that NP EBI2+ ASCs secret increased total and anti-dsDNA IgG compared with those from tonsils and had molecular features of mature plasma cell differentiation.

The effect of rs2910686 on ERAP2 expression in IBD and epithelial inflammatory response.

BACKGROUND: ERAP2 is an aminopeptidase involved in antigen processing and presentation, and harbor genetic variants linked to several inflammatory diseases such as Inflammatory Bowel Disease (IBD). The lack of an ERAP2 gene homologue in mice has hampered functional studies, and most human studies have focused on cells of hematopoietic origin. Using an IBD biobank as vantage point, this study explores how genetic variation in ERAP2 affects gene expression in human-derived epithelial organoids upon proinflammatory stimulation. METHODS: An IBD patient cohort was genotyped with regards to two single nucleotide polymorphisms (SNP) (rs2910686/rs2248374) associated with ERAP2 expression levels, and we examined the correlation between colon gene expression and genotype, specifically aiming to establish a relationship with ERAP2 expression proficiency. Human-derived colon organoids (colonoids) with known ERAP2 genotype were established and used to explore differences in whole genome gene expression between ERAP2-deficient (n = 4) and -proficient (n = 4) donors upon pro-inflammatory encounter. RESULTS: When taking rs2910686 genotype into account, ERAP2 gene expression is upregulated in the inflamed colon of IBD patients. Colonoids upregulate ERAP2 upon IFNÉ£ stimulation, and ERAP2 expression proficiency is dependent on rs2910686 genotype. Colonoid genotyping confirms that mechanisms independent of the frequently studied SNP rs2248374 can cause ERAP2-deficiency. A total of 586 genes involved in various molecular mechanisms are differentially expressed between ERAP2 proficient- and deficient colonoids upon proinflammatory stimulation, including genes encoding proteins with the following molecular function: catalytic activity (AOC1, CPE, ANPEP and MEP1A), regulator activity (TNFSF9, MDK, GDF15, ILR6A, LGALS3 and FLNA), transmembrane transporter activity (SLC40A1 and SLC5A1), and extracellular matrix structural constituents (FGL2, HMCN2, and MUC17). CONCLUSIONS: ERAP2 is upregulated in the inflamed IBD colon mucosa, and expression proficiency is highly correlated with genotype of rs2910686. While the SNP rs2248374 is commonly used to determine ERAP2 expressional proficiency, our data confirms that mechanisms independent of this SNP can lead to ERAP2 deficiency. Our data demonstrates that epithelial ERAP2 presence affects the inflammatory response in colonoids, suggesting a pleiotropic role of ERAP2 beyond MHC class I antigen processing.

The E3 ligase TRIM22 functions as a tumor suppressor in breast cancer by targeting CCS for proteasomal degradation to inhibit STAT3 signaling.

Deregulation of E3 ubiquitin ligases drives the proliferation and metastasis of various cancers; however, the underlying mechanisms remain unknown. This study aimed to investigate the role of tripartite motif-containing 22 (TRIM22), a poorly investigated E3 ubiquitin ligase in the TRIM family, as a tumor suppressor in breast cancer. High expression of TRIM22 in breast cancer correlated with better prognosis. Functional experiments demonstrated that TRIM22 significantly inhibited the proliferation and invasion of breast cancer cells. Label-free proteomics and biochemical analyses revealed that the copper chaperone for superoxide dismutase (CCS), an oncoprotein that is upregulated in breast cancer and promotes the growth and invasion of breast cancer cells, was a target of TRIM22 for degradation via K27-linked ubiquitination. Notably, the ability of the coiled-coil domain-defective mutants of TRIM22 to induce CCS ubiquitination and degradation diminished, with lysine 76 of the CCS serving as the ubiquitination site. Moreover, the TRIM22-mediated inhibition of the proliferation and invasion of breast cancer cells was restored by ectopic CCS expression. RNA-sequencing experiments using Gene Set Enrichment Analysis demonstrated that TRIM22 is involved in the JAK-STAT signaling pathway. TRIM22 overexpression also improved reactive oxygen species levels in breast cancer cells and inhibited STAT3 phosphorylation, which was restored via CCS overexpression or N-acetyl-l-cysteine treatment. Chromatin immunoprecipitation-quantitative polymerase chain reaction results showed that TRIM22 overexpression decreased the enrichment of phosphorylated STAT3 in FN1, VIM and JARID2 promoters. Clinically, low TRIM22 expression correlated with high CCS expression and decreased survival rates in patients with breast cancer. Moreover, TRIM22 upregulation was associated with a better prognosis in patients with breast cancer who received classical therapy. TRIM22 expression was downregulated in many cancer types, including colon, kidney, lung, and prostate cancers. To the best of our knowledge, the E3 ubiquitin ligase TRIM22 was first reported as a tumor suppressor that inhibits the proliferation and invasion of breast cancer cells through CCS ubiquitination and degradation. TRIM22 is a potential prognostic biomarker in patients with breast cancer.

Minor histocompatibility antigens to predict, monitor or manipulate GvL and GvHD after allogeneic hematopoietic cell transplantation.

Allogeneic hematopoietic cell transplantation (alloHCT) provides a potential curative treatment for haematological malignancies. The therapeutic Graft-versus-Leukaemia (GvL) effect is induced by donor T cells attacking patient hematopoietic (malignant) cells. However, if healthy non-hematopoietic tissues are targeted, Graft-versus-Disease (GvHD) may develop. After HLA-matched alloHCT, GvL and GvHD are induced by donor T cells recognizing polymorphic peptides presented by HLA on patient cells, so-called minor histocompatibility antigens (MiHAs). The balance between GvL and GvHD depends on the tissue distribution of MiHAs and T-cell frequencies targeting these MiHAs. T cells against broadly expressed MiHAs induce GvL and GvHD, whereas those targeting MiHAs with hematopoietic-restricted expression induce GvL without GvHD. Recently, the MiHA repertoire identified in natural immune responses after alloHCT was expanded to 159 total HLA-I-restricted MiHAs, including 14 hematopoietic-restricted MiHAs. This review explores their potential relevance to predict, monitor, and manipulate GvL and GvHD for improving clinical outcome after HLA-matched alloHCT.

ASCT2 is a major contributor to serine uptake in cancer cells.

The non-essential amino acid serine is a critical nutrient for cancer cells due to its diverse biosynthetic functions. While some tumors can synthesize serine de novo, others are auxotrophic and therefore reliant on serine uptake. Importantly, despite several transporters being known to be capable of transporting serine, the transporters that mediate serine uptake in cancer cells are not known. Here, we characterize the amino acid transporter ASCT2 (SLC1A5) as a major contributor to serine uptake in cancer cells. ASCT2 is well known as a glutamine transporter in cancer, and our work demonstrates that serine and glutamine compete for uptake through ASCT2. We further show that ASCT2-mediated serine uptake is essential for purine nucleotide biosynthesis and that estrogen receptor α (ERα) promotes serine uptake by directly activating SLC1A5 transcription. Collectively, our work defines an additional important role for ASCT2 as a serine transporter in cancer and evaluates ASCT2 as a potential therapeutic target.

Cutting Edge: Redundant Roles for MHC Class II-, CD1d-, and MR1-restricted T Cells in Clearing Bartonella Infection.

The importance of unconventional T cells for mucosal immunity is firmly established but for systemic bacterial infection remains less well defined. In this study, we explored the role of various T cell subsets in murine Bartonella infection, which establishes persistent bacteremia unless controlled by antibacterial Abs. We found that αß T cells are essential for Ab production against and clearance of B. taylorii, whereas MHC class I (MHC-I)- or MHC class II (MHC-II)-deficient mice eliminated B. taylorii infection with normal kinetics. Similarly, animals lacking either CD1d or MR1 suppressed bacteremia with normal kinetics. Interestingly, mice with a combined deficiency of either MHC-II and CD1d or MHC-II and MR1 failed to clear the infection, indicating that the combination of CD1d- and MR1-restricted T cells can compensate for the lack of MHC-II in this model. Our data document a previously underappreciated contribution of unconventional T cells to the control of systemic bacterial infection, supposedly as helper cells for antibacterial Ab production.

Biology of HLA class I associated inflammatory diseases.

Human leukocyte antigen (HLA) class I association is a well-established feature of common and uncommon inflammatory diseases, but it is unknown whether it impacts the pathogenesis of these disorders. The "arthritogenic peptide" hypothesis proposed initially for HLA-B27-associated ankylosing spondylitis (AS) seems the most intuitive to serve as a model for other HLA class I-associated diseases, but evidence supporting it has been scarce. Recent technological advances and the discovery of epistatic relationships between disease-associated HLA class I and endoplasmic reticulum aminopeptidase (ERAP) coding variants have led to the generation of new data and conceptual approaches to the problem requiring its re-examination. Continued success in these endeavors holds promise to resolve a Gordian Knot in human immunobiology. It may ultimately benefit patients by enabling the development of new therapies and precision tools for assessing disease risk and predicting treatment responses.

Specific association of MTHFD1 expressions with small cell lung cancer development and chemoradiotherapy outcome.

OBJECTIVES: To identify biomarkers that can discriminated small cell lung cancer (SCLC) from non-SCLC (NSCLC), and explore their association with the prognosis of SCLC under chemoradiotherapy. METHODS: The GSE40275 dataset was used to identify potential targets in SCLC. There were 196 patients of lung cancer (LC) in cohort 1 of this study. MTHFD1 levels in tissues were determined by immunohistochemistry assay in cohort 1. Lung cancer patients who were all underwent local chemoradiotherapy (CRT) were included in cohort 2, and the association of MTHFD1 levels with CRT treatment outcome were determined in cohort 2. Cell experiments were used to determine the function of MTHFD1 on the radio-sensitivity of SCLC and NSCLC cells. RESULTS: The MTHFD1 levels in LC tissues were increased, and could discriminate SCLC from both lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD). Small cell lung cancer patients with MTHFD1 high phenotype had a poorer prognosis after CRT treatment, whereas no significant correlation was found between MTHFD1 levels and prognosis in LUSC and LUAD group. Cell experiments demonstrated that overexpression of MTHFD1 increases radio-resistance in both SCLC and NSCLC in vitro. CONCLUSION: MTHFD1 expressions might be a novel specifically prognostic biomarker for SCLC and the CRT treatment outcome.

[Relationship between maternal and fetal ERAP-1 gene polymorphism and pre-eclampsia].

Objective: To investigate the relationship between the polymorphism of endoplasmic reticulum aminopeptidase 1 (ERAP-1) gene and the occurrence of pre-eclampsia (PE). Methods: A case-control study was conducted in Beijing Obstetrics and Gynecology Hospital from October 2018 to October 2021. A total of 51 PE pregnant women with onset gestational age<34 weeks were selected as the PE group, and 48 normal pregnant women during the same period were selected as the control group. Venous blood samples were collected from the pregnant women before delivery and umbilical cord within 5 minutes after delivery. Single nucleotide polymorphisms (SNP) of ERAP-1 gene in the pregnant women and their fetus were detected by next-generation sequencing. Univariate analysis and multivariate logistic regression analysis were used to analyze all the SNP loci and alleles detected in the two groups, and the significant SNP were screened. Results: (1) A total of 13 target SNP loci of maternal ERAP-1 gene were selected by univariate analysis. Among them, the frequency distribution of genotypes at 96096828, 96121524, 96121715, 96122260 and 96122281 showed statistically significant differences between PE group and control group (all P<0.05). Multivariate logistic regression analysis showed that the risk of PE in pregnant women with TC genotype at locus 96121524 was 2.002 times higher than those with TT genotype (95%CI: 0.687-5.831, P=0.020). (2) A total of 4 target SNP loci of ERAP-1 gene in fetal were selected by univariate analysis, and there was no statistical significance in gene polymorphism of the 4 loci between PE group and control group (all P>0.05). Multivariate logistic regression analysis showed that the risk of PE in fetus with genotype AA at locus 96121406 was 0.236 times that of fetus with genotype GG (95%CI: 0.055-1.025, P=0.016). Conclusion: ERAP-1 gene with TC genotype at 96121524 in the mother and GG genotype at 96121406 in the fetus might be related to the incidence of PE.

Carnosic Acid: A Novel Selective Inhibitor of ERAP1 by Direct Binding and Its Modulation of Antigen Processing and Presentation.

ERAP1 is an emerging target for a large subclass of severe autoimmune diseases known as "MHC-I-opathy", together with tumor immunity. Nevertheless, effective inhibitors targeting ERAP1 remain a challenge. In this study, a novel food-derived natural product ERAP1-targeting inhibitor, carnosic acid, was identified, and to our knowledge, it is one of the best active compounds among the highly selective inhibitors targeting the orthosteric site of ERAP1. The results reveal that carnosic acid could bind strongly, like a key to the ERAP1 active site in the biased S1' pocket, which is different from the binding mode of the existing orthosteric site inhibitors. HLA-B27-mediated cell modeling validated that carnosic acid has the activity to reverse the AS-associated cellular phenotype brought on by ERAP1 through inhibition. Our findings provide insights into the design of potent inhibitors against the ERAP1 orthosteric site and the discovery of a key direct target of carnosic acid.

Reprogramming of Glutamine Amino Acid Transporters Expression and Prognostic Significance in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the most prevalent primary liver malignancy and is a major cause of cancer-related mortality in the world. This study aimed to characterize glutamine amino acid transporter expression profiles in HCC compared to those of normal liver cells. In vitro and in vivo models of HCC were studied using qPCR, whereas the prognostic significance of glutamine transporter expression levels within patient tumors was analyzed through RNAseq. Solute carrier (SLC) 1A5 and SLC38A2 were targeted through siRNA or gamma-p-nitroanilide (GPNA). HCC cells depended on exogenous glutamine for optimal survival and growth. Murine HCC cells showed superior glutamine uptake rate than normal hepatocytes (p < 0.0001). HCC manifested a global reprogramming of glutamine transporters compared to normal liver: SLC38A3 levels decreased, whereas SLC38A1, SLC7A6, and SLC1A5 levels increased. Also, decreased SLC6A14 and SLC38A3 levels or increased SLC38A1, SLC7A6, and SLC1A5 levels predicted worse survival outcomes (all p < 0.05). Knockdown of SLC1A5 and/or SLC38A2 expression in human Huh7 and Hep3B HCC cells, as well as GPNA-mediated inhibition, significantly decreased the uptake of glutamine; combined SLC1A5 and SLC38A2 targeting had the most considerable impact (all p < 0.05). This study revealed glutamine transporter reprogramming as a novel hallmark of HCC and that such expression profiles are clinically significant.

Association of Endoplasmic Reticulum Aminopeptidase 1 Gene Polymorphism with Susceptibility and Severity of Axial Spondyloarthritis in Egyptian Population: A Single-center Case-Control Study.

BACKGROUND: Axial spondyloarthritis (axSpA) is a systemic, progressive, autoimmune disease. Complex interactions between environmental factors and host immune responses are the origin of axSpA. Together with human leukocyte antigen (HLA-B27), endoplasmic reticulum aminopeptidase 1 (ERAP1) gene is a potential non-HLA contributor to axSpA susceptibility. AIM: This study aimed to identify the role of ERAP1 single-nucleotide polymorphisms (SNPs) (rs30187, rs27044, and rs27037) in susceptibility to and severity of axSpA in Egyptian patients. METHODS: In this case-control study, we enrolled 120 patients with axSpA and 120 healthy individuals as controls. Real-time polymerase chain reaction was used to identify ERAP1 polymorphisms. RESULTS: The present study revealed no significant association between ERAP1 SNPs (rs30187, rs27044, and rs27037) and axSpA susceptibility in Egyptian patients. A significant relationship was found only between the ERAP1 SNP rs27037 "GT" genotype and axSpA HLA-B27-positive cases, demonstrating a functional interaction between ERAP1 and HLA-B27-positive cases. Our analysis revealed a significant association between the ERAP1 SNP rs27037 "GT and TT" genotypes and Bath Ankylosing Spondylitis Disease Activity Index, in addition to an association between the ERAP1 SNP rs27037 "TT" genotype and active enthesitis. The ERAP1 SNP rs27044 "GG" genotype was significantly associated with active enthesitis, but not with clinical axial involvement. Finally, we did not observe a significant relationship between HLA-B27 positivity and disease severity in the studied cases. CONCLUSION: Three SNPs (rs30187, rs27044, and rs27037) in ERAP1 do not confer susceptibility to axSpA in Egyptian patients. This association existed exclusively between the ERAP1 SNP (rs27037) "GT" genotype and axSpA HLA-B27-positive cases.

Résumé Contexte:la spondyloarthrite axiale (SpAx) est une maladie auto-immune systémique et progressive. Les interactions complexes entre les facteurs environnementaux et les réponses immunitaires de l'hôte sont à l'origine de la SpAx. En plus de l'antigène leucocytaire humain (HLAB27), le gène de l'aminopeptidase du réticulum endoplasmique 1 (ERAP1) est un contributeur potentiel non-HLA à la susceptibilité à la SpAx.Objectif:cette étude visait à identifier le rôle des polymorphismes mononucléotidiques (SNP) de l'ERAP1 (rs30187, rs27044 et rs27037) dans la susceptibilité et la gravité de la SpAx chez les patients égyptiens.Méthodes:dans cette étude cas-témoins, nous avons inclus 120 patients atteints de SpAx et 120 individus en bonne santé comme témoins. La réaction en chaîne de la polymérase en temps réel a été utilisée pour identifier les polymorphismes de l'ERAP1.Résultats:cette étude a révélé qu'il n'y avait pas d'association significative entre les SNP de l'ERAP1 (rs30187, rs27044 et rs27037) et la susceptibilité à la SpAx chez les patients égyptiens. Une relation significative a été trouvée uniquement entre le génotype "GT" du SNP rs27037 de l'ERAP1 et les cas de SpAx positifs pour le HLA-B27, démontrant une interaction fonctionnelle entre l'ERAP1 et les cas positifs pour le HLA-B27. Notre analyse a révélé une association significative entre les génotypes "GT et TT" du SNP rs27037 de l'ERAP1 et l'indice d'activité de la maladie de spondylarthrite ankylosante de Bath, ainsi qu'une association entre le génotype "TT" du SNP rs27037 de l'ERAP1 et l'enthésite active. Le génotype "GG" du SNP rs27044 de l'ERAP1 était significativement associé à l'enthésite active, mais non à l'atteinte axiale clinique. Enfin, nous n'avons pas observé de relation significative entre la positivité du HLA-B27 et la gravité de la maladie dans les cas étudiés.Conclusion:trois SNP (rs30187, rs27044 et rs27037) dans l'ERAP1 ne confèrent pas de susceptibilité à la SpAx chez les patients égyptiens. Cette association existait exclusivement entre le génotype "GT" du SNP rs27037 de l'ERAP1 et les cas de SpAx positifs pour le HLA-B27.

Congenital Heart Disease and Genetic Changes in Folate/Methionine Cycles.

Congenital heart disease is one of the most common congenital malformations and thus represents a considerable public health burden. Hence, the identification of individuals and families with an increased genetic predisposition to congenital heart disease (CHD) and its possible prevention is important. Even though CHD is associated with the lack of folate during early pregnancy, the genetic background of folate and methionine metabolism perturbations and their influence on CHD risk is not clear. While some genes, such as those coding for cytosolic enzymes of folate/methionine cycles, have been extensively studied, genetic studies of folate transporters (de)glutamation enzymes and mitochondrial enzymes of the folate cycle are lacking. Among genes coding for cytoplasmic enzymes of the folate cycle, MTHFR, MTHFD1, MTR, and MTRR have the strongest association with CHD, while among genes for enzymes of the methionine cycle BHMT and BHMT2 are the most prominent. Among mitochondrial folate cycle enzymes, MTHFD2 plays the most important role in CHD formation, while FPGS was identified as important in the group of (de)glutamation enzymes. Among transporters, the strongest association with CHD was demonstrated for SLC19A1.

Co-Expression Network Analysis and Molecular Docking Demonstrate That Diosgenin Inhibits Gastric Cancer Progression via SLC1A5/mTORC1 Pathway.

Background: Tumor-Node-Metastasis (TNM) stage of gastric cancer (GC) is one of the main factors affecting clinical outcome. The aim of this study was to explore the targets related to TNM stage of GC, and screening natural bioactive drug. Methods: RNA sequencing data of the TCGA-STAD cohort were downloaded from UCSC database. Genes associated with TNM staging were identified by weighted gene co-expression network analysis (WGCNA). Univariate Cox regression, least absolute shrinkage and selection operator (LASSO), extreme gradient boosting (Xgboost), random forest (RF) and cytohubba plug-in of cytoscope were applied to screen hub genes. Natural bioactive ingredients were available from the HERB database. Molecular docking was used to evaluate the binding activity of active ingredients to the hub protein. CCK-8, flow cytometry, transwell and Western blot assays were used to analyze the effects of diosgenin on GC cells. Results: 898 TNM-related genes were screened out through WGCNA. Three genes associated with GC progression/prognosis were identified, including nuclear receptor subfamily 3 group C member 2 (NR3C2), solute carrier family 1 member 5 (SLC1A5) and FAT atypical cadherin 1 (FAT1) based on the machine learning algorithms and hub co-expression network analysis. Diosgenin had good binding activity with SLC1A5. SLC1A5 was highly expressed in GC and was closely associated with tumor stage, overall survival and immune infiltration of GC patients. Diosgenin could inhibit cell viability and invasive ability, promote apoptosis and induce cell cycle arrest in G0/G1 phase. In addition, diosgenin promoted cleaved caspase 3 expression and inhibited Ki67, cyclin D1, p-S6K1, and SLC1A5 expression levels, while the mTORC1 activator (MHY1485) reversed this phenomenon. Conclusion: For the first time, this work reports diosgenin may inhibit the activation of mTORC1 signaling through targeting SLC1A5, thereby inhibiting the malignant behaviors of GC cells.

The tRNA Gm18 methyltransferase TARBP1 promotes hepatocellular carcinoma progression via metabolic reprogramming of glutamine.

Cancer cells rely on metabolic reprogramming to sustain the prodigious energetic requirements for rapid growth and proliferation. Glutamine metabolism is frequently dysregulated in cancers and is being exploited as a potential therapeutic target. Using CRISPR/Cas9 interference (CRISPRi) screening, we identified TARBP1 (TAR (HIV-1) RNA Binding Protein 1) as a critical regulator involved in glutamine reliance of cancer cell. Consistent with this discovery, TARBP1 amplification and overexpression are frequently observed in various cancers. Knockout of TARBP1 significantly suppresses cell proliferation, colony formation and xenograft tumor growth. Mechanistically, TARBP1 selectively methylates and stabilizes a small subset of tRNAs, which promotes efficient protein synthesis of glutamine transporter-ASCT2 (also known as SLC1A5) and glutamine import to fuel the growth of cancer cell. Moreover, we found that the gene expression of TARBP1 and ASCT2 are upregulated in combination in clinical cohorts and their upregulation is associated with unfavorable prognosis of HCC (hepatocellular carcinoma). Taken together, this study reveals the unexpected role of TARBP1 in coordinating the tRNA availability and glutamine uptake during HCC progression and provides a potential target for tumor therapy.