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Biochemical and Biophysical Research... Jun 2024Among the various RNA modifications, adenosine-to-inosine RNA editing, catalyzed by adenosine deaminase acting on RNA (ADAR) family, ADAR1 and ADAR2, is the most common...
Among the various RNA modifications, adenosine-to-inosine RNA editing, catalyzed by adenosine deaminase acting on RNA (ADAR) family, ADAR1 and ADAR2, is the most common nucleotide conversion in mammalian cells. The pathological relevance of ADAR expression has been highlighted in recent human genetic studies. Low expression of the ADAR2 gene is correlated with a poor prognosis in breast cancer patients, but the underlying mechanism remains enigmatic. In this study, we constructed Adar2-knockdown (Adar2-KD) murine breast cancer 4T1 cells and observed their reduced susceptibility to chemotherapeutic drug doxorubicin. Downregulation of ADAR2 induced the expression of P-glycoprotein (P-gp), leading to a reduction in the intracellular accumulation of doxorubicin. The upregulation of P-gp occurred at the post-transcriptional level due to the decreased miR-195a-3p function. The search for the underlying cause of the induction of P-gp expression in Adar2-KD 4T1 cells led to the identification of circular RNA (circRNA) circHif1a as a sponge for miR-195a-3p. The enhanced expression of circHif1a inhibited miR-195a-3p function, resulting in the upregulation of P-gp expression. These results suggest that ADAR2 acts as a suppressor of circHif1a biogenesis and then allows miR-195a-3p to interfere with P-gp translation. Our findings may help to improve drug efficacy by clarifying the mechanism of chemoresistance in breast cancer.
PubMed: 38917633
DOI: 10.1016/j.bbrc.2024.150289 -
Oncoimmunology 2024Improving cancer immunotherapy efficacy hinges on identifying key T-cell populations critical for tumor control and response to Immune Checkpoint Blockade (ICB). We have...
Improving cancer immunotherapy efficacy hinges on identifying key T-cell populations critical for tumor control and response to Immune Checkpoint Blockade (ICB). We have recently reported that while the co-expression of PD-1 and CD28 is associated with impaired functionality in peripheral blood, it significantly enhances T-cell fitness in the tumor site of non-small cell lung cancer (NSCLC) patients. To uncover the underlying mechanisms, we explored the role of CD26, a key player in T-cell activation through its interaction with adenosine deaminase (ADA), a crucial intra/extracellular enzyme able to neutralize local adenosine (ADO). We found that an autocrine ADA/CD26 axis enhances CD8PD-1CD28 T-cell function, particularly within an immunosuppressive environment marked by CD39 expression. Then, we interrogated the TCGA and OAK datasets to gain insight into the prognostic/predictive potential of our findings. We identified a signature predicting overall survival (OS) in LUAD patients and response to atezolizumab in advanced LUAD cases. These findings suggest promising avenues for therapeutic intervention targeting the ADA/CD26 axis.
Topics: Humans; Carcinoma, Non-Small-Cell Lung; Lung Neoplasms; CD8-Positive T-Lymphocytes; CD28 Antigens; Prognosis; Programmed Cell Death 1 Receptor; Dipeptidyl Peptidase 4; Adenosine Deaminase; Immune Checkpoint Inhibitors; Antibodies, Monoclonal, Humanized; Female; Male; Apyrase
PubMed: 38915783
DOI: 10.1080/2162402X.2024.2371051 -
BioRxiv : the Preprint Server For... Jun 2024Endogenous U small nuclear RNAs (U snRNAs) form RNA-protein complexes responsible for eukaryotic processing of pre-mRNA into mature mRNA. Previous studies have...
Endogenous U small nuclear RNAs (U snRNAs) form RNA-protein complexes responsible for eukaryotic processing of pre-mRNA into mature mRNA. Previous studies have demonstrated the utility of guide-programmable U snRNAs in targeted exon inclusion and exclusion. We investigated whether snRNAs can also enhance conversion of RNA bases over state-of-the-art RNA targeting technologies in human cells. When compared to adenosine deaminase acting on RNA (ADAR)-recruiting circular RNAs, we find that guided A>I snRNAs consistently increase adenosine-to-inosine editing efficiency for genes with higher exon counts, perturb substantially fewer genes in the transcriptome, and localize more persistently to the nucleus where ADAR is expressed. A>I snRNAs can also edit pre-mRNA 3' splice sites to promote splicing changes. Finally, snRNA fusions to H/ACA box snoRNAs (U>Ψ snRNAs) increase targeted RNA pseudouridylation efficiency. Altogether, our results advance the protein-free RNA base conversion toolbox and enhance minimally invasive RNA targeting technologies to treat genetic diseases.
PubMed: 38915553
DOI: 10.1101/2024.06.12.598766 -
International Immunopharmacology Jun 2024Severe combined immunodeficiency (SCID) is the most fatal form of inherited primary immunodeficiency disease. Known molecular defect mutations occur in most children...
BACKGROUND
Severe combined immunodeficiency (SCID) is the most fatal form of inherited primary immunodeficiency disease. Known molecular defect mutations occur in most children with SCID.
METHODS
Herein, we report Adenosine Deaminase-SCID (ADA-SCID) using whole-exome sequencing (WES), explore exome mutational landscape and significance for 17 SCID samples, and verify the mutated exon genes using the Gene Expression Omnibus (GEO) datasets. A total of 250 patients, who were hospitalized at the Neonatal Intensive Care Unit (NICU) of The Seventh Medical Center of the PLA General Hospital for 3 years (from 2017 to 2020), were screened for SCID. We collected mutated genes from the WES data of 17 SCID children. GSE609 and GSE99176 cohorts were used to identify the expressions of mutated exon genes and molecular features in SCID. Gene set variation analyses (GSVA) and correlation analyses were performed.
RESULTS
The detection rate with approximately 6.8 % (17/250) of SCID is high in the NICU. A total of 16 genes were identified among 17 SCID samples, of which the Top 2 genes (MUC6 and RP11-683L23.1) might be crucial in the progression of SCID with 94 % mutation frequency. Furthermore, CNN2 and SCGB1C1 had significant co-mutations and may cooperate to affect SCID development. Importantly, the phylogenetic tree classification results of 17 SCID samples are more correlated to MUC6 with the most significant mutations. Expression profiles of seven mutated genes and five mutated genes were documented in GSE609 and GSE99176 cohorts based on microarray, respectively. Several immune-related pathways were significantly enriched, and Foxd4, differing from the other four mutated genes, was inversely correlated with the GSVA-enriched pathway.
CONCLUSION
Due to its high detection rate (6.8%) and fatality rate (100%), the inclusion of SCID in newborn screening (NBS) is urgent for children in China. The WES successfully identified several common exonic variants (e.g., MUC6) and depicted the feature of mutations and evolution, which will help develop new diagnostic methods for SCID.
PubMed: 38908084
DOI: 10.1016/j.intimp.2024.112402 -
International Journal of Molecular... May 2024A-to-I RNA editing, catalyzed by the ADAR protein family, significantly contributes to the diversity and adaptability of mammalian RNA signatures, aligning with...
A-to-I RNA editing, catalyzed by the ADAR protein family, significantly contributes to the diversity and adaptability of mammalian RNA signatures, aligning with developmental and physiological needs. Yet, the functions of many editing sites are still to be defined. The gene stands out in this context due to its brain-specific expression and the evolutionary conservation of its codon-altering editing event. The precise biological functions of and its editing, however, are still largely undefined. In this study, we first demonstrated that editing occurs in an ADAR2-dependent manner and is exclusive to the brain. By employing the CRISPR/Cas9 system to generate knock-in mouse models that replicate the natural editing variations, our findings revealed that mice with the "gain-of-editing" variant () exhibit heightened basal neuronal activity in critical olfactory regions, compared to the "loss-of-editing" () counterparts. Moreover, an increase in glutamate levels was observed in the olfactory bulbs of mice, indicating altered neurotransmitter dynamics. Behavioral analysis of odor detection revealed distinctive responses to novel odors-both deficient () and mice demonstrated prolonged exploration times and heightened dishabituation responses. Further elucidating the olfactory connection of editing, transcriptomic analysis of the olfactory bulb identified significant alterations in gene expression that corroborate the behavioral and physiological findings. Collectively, our research advances the understanding of 's neurophysiological functions and the impact of its editing on the olfactory sensory system, shedding light on the intricate molecular underpinnings of olfactory perception and neuronal activity.
Topics: Animals; RNA Editing; Mice; Olfactory Perception; Adenosine Deaminase; Olfactory Bulb; RNA-Binding Proteins; Neurons; CRISPR-Cas Systems; Male; Mice, Inbred C57BL; Nerve Tissue Proteins
PubMed: 38892173
DOI: 10.3390/ijms25115985 -
International Journal of Molecular... May 2024The dynamic process of spermatogenesis involves asymmetric division, mitosis, and meiosis, which ultimately results in the production of mature spermatozoa. Disorders...
The dynamic process of spermatogenesis involves asymmetric division, mitosis, and meiosis, which ultimately results in the production of mature spermatozoa. Disorders of spermatogenesis can lead to infertility in males. ADAR (adenosine deaminase acting on RNA) mutations in cause male infertility, yet the causative factors remain unclear. In this study, immunofluorescence staining was employed to visualize endogenous ADAR proteins and assess protein levels via fluorescence-intensity analysis. In addition, the early differentiation disorders and homeostatic alterations during early spermatogenesis in the testes were examined through quantification of transit-amplifying region length, counting the number of GSCs (germline stem cells), and fertility experiments. Our findings suggest that deletion of ADAR causes testicular tip transit-amplifying cells to accumulate and become infertile in older male . By overexpressing ADAR in early germline cells, male infertility can be partially rescued. Transcriptome analysis showed that ADAR maintained early spermatogenesis homeostasis through the bone-morphogenetic-protein (BMP) signaling pathway. Taken together, these findings have the potential to help explore the role of ADAR in early spermatogenesis.
Topics: Animals; Male; Spermatogenesis; Drosophila melanogaster; Signal Transduction; Drosophila Proteins; Adenosine Deaminase; Bone Morphogenetic Proteins; Infertility, Male; RNA-Binding Proteins; Testis
PubMed: 38891830
DOI: 10.3390/ijms25115643 -
BMJ Case Reports Jun 2024Rheumatoid pleurisy is common in patients with rheumatoid arthritis, but distinguishing it from other diseases, such as heart failure and tuberculous pleurisy, is often...
Rheumatoid pleurisy is common in patients with rheumatoid arthritis, but distinguishing it from other diseases, such as heart failure and tuberculous pleurisy, is often difficult. A man in his 70s with stable rheumatoid arthritis presented with cardiac enlargement and bilateral pleural effusion on chest radiography. Pleural fluid studies showed lymphocytosis, adenosine deaminase level of 51.6 U/L and rheumatoid factor level of 2245.3 IU/mL, suggestive of rheumatoid pleurisy and tuberculous pleurisy. Thoracoscopy under local anaesthesia revealed erythema of the parietal pleura, small papillary projections and fibrin deposits. H&E-stained biopsy specimens showed inflammatory granulomas with strong lymphocytic infiltration and non-caseating granulomas. He was diagnosed with rheumatoid pleurisy. His symptoms improved with 30 mg of prednisolone. This study highlights that biopsy using thoracoscopy under local anaesthesia effectively diagnoses rheumatoid pleurisy, which may be challenging to diagnose.
Topics: Humans; Male; Thoracoscopy; Anesthesia, Local; Pleurisy; Aged; Biopsy; Thoracic Wall; Diagnosis, Differential; Arthritis, Rheumatoid; Prednisolone; Pleura
PubMed: 38885997
DOI: 10.1136/bcr-2024-260140 -
BMJ Case Reports Jun 2024Drug-induced pleural effusion is one of the rare causes of exudative pleural effusion and a high index of suspicion is necessary to lead to early diagnosis. We hereby...
Drug-induced pleural effusion is one of the rare causes of exudative pleural effusion and a high index of suspicion is necessary to lead to early diagnosis. We hereby present the case of a young male in his late 30s, known case of metastatic gastrointestinal stromal tumour on sunitinib therapy, who presented with right-sided mild pleural effusion. Diagnostic thoracentesis showed the effusion to be a monomorphic exudate with low adenosine deaminase, which was negative for malignant cells on cytopathology. A contrast-enhanced CT chest revealed an enlarged lymph node (LN) at the 4R station, cytological analysis of which was suggestive of reactive lymphoid hyperplasia. Infective workup of the LN aspirate and bronchoalveolar lavage taken from the right middle lobe was negative. After systematically excluding the usual causes of exudative pleural effusion, sunitinib was considered to be a possible cause and was, therefore, withheld. A repeat chest X-ray after 3 weeks of stopping the drug showed resolution of the pleural effusion.
Topics: Humans; Male; Sunitinib; Pleural Effusion; Adult; Antineoplastic Agents; Gastrointestinal Stromal Tumors; Tomography, X-Ray Computed; Thoracentesis; Indoles
PubMed: 38885996
DOI: 10.1136/bcr-2023-257191 -
Journal of Thoracic Disease May 2024Lactate dehydrogenase (LDH), total protein (TP) and glucose (Glu) in pleural hydrothorax and ascites can be used in the diagnosis of exudate, and adenosine deaminase...
BACKGROUND
Lactate dehydrogenase (LDH), total protein (TP) and glucose (Glu) in pleural hydrothorax and ascites can be used in the diagnosis of exudate, and adenosine deaminase (ADA) can be used in the diagnosis of tuberculous effusion. However, the manufacturers do not claim that their biochemical reagents can be used to detect hydrothorax and ascites samples. Therefore, medical laboratories must conduct suitability studies on biochemical reagents for hydrothorax and ascites samples to comply with regulatory requirements for humor detection. This study aimed to verify the analytical performance and clinical diagnostic accuracy of the Mindray biochemical reagents, including LDH, TP, Glu and ADA, for hydrothorax and ascites.
METHODS
The repeatability, detection limits and reference intervals of Mindray biochemical reagents (LDH, TP, Glu, ADA) in detecting hydrothorax and ascites were determined. The comparison of different measurement procedures was performed. Meanwhile, the diagnostic accuracy of LDH, TP, Glu and ADA were assessed.
RESULTS
The quality control results of LDH, TP, Glu, and ADA were all under control. The repeatability coefficient of variation (%) of LDH, TP, Glu, and ADA were all less than 1%. The limits of blank of LDH, TP, Glu, and ADA were 0.33 U/L, 0.45 g/L, 0.00 mmol/L, and 0.04 U/L, respectively; the limits of detection were 1.57 U/L, 1.85 g/L, 0.05 mmol/L, and 0.12 U/L, respectively. Compared with the reference measurement program, the correlation coefficients of LDH, TP, Glu and ADA were 0.9931, 0.9983, 0.9996 and 0.9966, respectively; the regression equations were y=1.0082x-10.06, y=0.9965x-0.4732, y=0.9903x+0.0522 and y=1.0051x-0.0232, respectively. The reference intervals of LDH, TP, Glu, and ADA in hydrothorax and ascites were ≤198.39 U/L, ≤32.97 g/L, ≥5.03 mmol/L. and ≤11.00 U/L respectively. For differentiating between exudates and transudates, the area under the curve (AUC) of LDH, TP, and Glu were 0.913, 0.875, and 0.767, respectively; the AUC of ADA for the differential diagnosis of tuberculous and nontuberculous effusions was 0.876.
CONCLUSIONS
The LDH, TP, Glu, and ADA assays were validated for use with the Mindray BS-2800 analyzer for hydrothorax and ascites evaluation. LDH, TP, and Glu in hydrothorax and ascites are applicable to the differential diagnosis of exudates and transudates; ADA in hydrothorax and ascites can be employed to differentiate and diagnose tuberculous and nontuberculous effusions.
PubMed: 38883656
DOI: 10.21037/jtd-24-345 -
SAGE Open Medical Case Reports 2024Deficiency of adenosine deaminase 2 is a rare monogenic multi-organ disease of children and less often adults resulting from mutations in the adenosine deaminase 2 gene....
Deficiency of adenosine deaminase 2 is a rare monogenic multi-organ disease of children and less often adults resulting from mutations in the adenosine deaminase 2 gene. We present a case of a 35-year-old Palestinian male with adenosine deaminase 2 deficiency and maturity-onset diabetes of the young type 2. The patient initially presented with complaints of swelling in his neck and night sweats, leading to a diagnosis of Hodgkin lymphoma. Subsequent evaluation revealed a recurrence of Hodgkin lymphoma, along with symptoms of otitis media, upper respiratory tract infection, and a rash around the mouth. Genetic testing confirmed mutations in the adenosine deaminase 2 gene and glucokinase genes, confirming the diagnosis of deficiency of adenosine deaminase 2 and maturity-onset diabetes of the young type 2, respectively. The patient was treated with Intravenous immunoglobulin, antiviral drugs, and oral hypoglycemic drugs, showing improvement in symptoms and laboratory tests. This case highlights the importance of considering rare genetic disorders in patients with unusual or refractory clinical manifestations, and the need for a multidisciplinary approach in such cases.
PubMed: 38881977
DOI: 10.1177/2050313X241260148