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1.
Int J Biol Sci ; 20(7): 2576-2591, 2024.
Article En | MEDLINE | ID: mdl-38725862

We showed that microtubule-associated tumor suppressor gene (MTUS1/ATIP) downregulation correlated with poor survival in head and neck squamous cell carcinoma (HNSCC) patients and that MTUS1/ATIP1 was the most abundant isoform in HNSCC tissue. However, the location and function of MTUS1/ATIP1 have remain unclear. In this study, we confirmed that MTUS1/ATIP1 inhibited proliferation, growth and metastasis in HNSCC in cell- and patient-derived xenograft models in vitro and in vivo. MTUS1/ATIP1 localized in the outer mitochondrial membrane, influence the morphology, movement and metabolism of mitochondria and stimulated oxidative stress in HNSCC cells by directly interacting with MFN2. MTUS1/ATIP1 activated ROS, recruiting Bax to mitochondria, facilitating cytochrome c release to the cytosol to activate caspase-3, and inducing GSDME-dependent pyroptotic death in HNSCC cells. Our findings showed that MTUS1/ATIP1 localized in the outer mitochondrial membrane in HNSCC cells and mediated anticancer effects through ROS-induced pyroptosis, which may provide a novel therapeutic strategy for HNSCC treatment.


Head and Neck Neoplasms , Mitochondria , Pyroptosis , Reactive Oxygen Species , Squamous Cell Carcinoma of Head and Neck , Humans , Reactive Oxygen Species/metabolism , Head and Neck Neoplasms/metabolism , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/genetics , Animals , Cell Line, Tumor , Mitochondria/metabolism , Squamous Cell Carcinoma of Head and Neck/metabolism , Squamous Cell Carcinoma of Head and Neck/pathology , Squamous Cell Carcinoma of Head and Neck/genetics , Mice , Mitochondrial Proteins/metabolism , Mitochondrial Proteins/genetics , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/genetics , Mice, Nude , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Mitochondrial Membranes/metabolism , Cell Proliferation
2.
Commun Biol ; 7(1): 549, 2024 May 09.
Article En | MEDLINE | ID: mdl-38724689

Amphiphysin 2 (BIN1) is a membrane and actin remodeling protein mutated in congenital and adult centronuclear myopathies. Here, we report an unexpected function of this N-BAR domain protein BIN1 in filopodia formation. We demonstrated that BIN1 expression is necessary and sufficient to induce filopodia formation. BIN1 is present at the base of forming filopodia and all along filopodia, where it colocalizes with F-actin. We identify that BIN1-mediated filopodia formation requires IRSp53, which allows its localization at negatively-curved membrane topologies. Our results show that BIN1 bundles actin in vitro. Finally, we identify that BIN1 regulates the membrane-to-cortex architecture and functions as a molecular platform to recruit actin-binding proteins, dynamin and ezrin, to promote filopodia formation.


Actins , Adaptor Proteins, Signal Transducing , Nerve Tissue Proteins , Pseudopodia , Tumor Suppressor Proteins , Pseudopodia/metabolism , Actins/metabolism , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Humans , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Animals , Nerve Tissue Proteins/metabolism , Nerve Tissue Proteins/genetics , Cell Membrane/metabolism , Mice , Nuclear Proteins/metabolism , Nuclear Proteins/genetics
3.
Biol Res ; 57(1): 25, 2024 May 08.
Article En | MEDLINE | ID: mdl-38720397

PURPOSE: Prostate cancer (PCa) is a major urological disease that is associated with significant morbidity and mortality in men. LLGL2 is the mammalian homolog of Lgl. It acts as a tumor suppressor in breast and hepatic cancer. However, the role of LLGL2 and the underlying mechanisms in PCa have not yet been elucidated. Here, we investigate the role of LLGL2 in the regulation of epithelial-mesenchymal transition (EMT) in PCa through autophagy in vitro and in vivo. METHODS: PC3 cells were transfected with siLLGL2 or plasmid LLGL2 and autophagy was examined. Invasion, migration, and wound healing were assessed in PC3 cells under autophagy regulation. Tumor growth was evaluated using a shLLGL2 xenograft mouse model. RESULTS: In patients with PCa, LLGL2 levels were higher with defective autophagy and increased EMT. Our results showed that the knockdown of LLGL2 induced autophagy flux by upregulating Vps34 and ATG14L. LLGL2 knockdown inhibits EMT by upregulating E-cadherin and downregulating fibronectin and α-SMA. The pharmacological activation of autophagy by rapamycin suppressed EMT, and these effects were reversed by 3-methyladenine treatment. Interestingly, in a shLLGL2 xenograft mouse model, tumor size and EMT were decreased, which were improved by autophagy induction and worsened by autophagy inhibition. CONCLUSION: Defective expression of LLGL2 leads to attenuation of EMT due to the upregulation of autophagy flux in PCa. Our results suggest that LLGL2 is a novel target for alleviating PCa via the regulation of autophagy.


Autophagy , Epithelial-Mesenchymal Transition , Prostatic Neoplasms , Animals , Humans , Male , Mice , Autophagy/physiology , Autophagy/genetics , Cell Line, Tumor , Cell Movement/genetics , Epithelial-Mesenchymal Transition/genetics , Gene Silencing , Mice, Nude , Prostatic Neoplasms/pathology , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
4.
Int J Mol Sci ; 25(9)2024 Apr 23.
Article En | MEDLINE | ID: mdl-38731819

TP53 mutations are prevalent in various cancers, yet the complexity of apoptotic pathway deregulation suggests the involvement of additional factors. HOPS/TMUB1 is known to extend the half-life of p53 under normal and stress conditions, implying a regulatory function. This study investigates, for the first time, the potential modulatory role of the ubiquitin-like-protein HOPS/TMUB1 in p53-mutants. A comprehensive analysis of apoptosis in the most frequent p53-mutants, R175, R248, and R273, in SKBR3, MIA PaCa2, and H1975 cells indicates that the overexpression of HOPS induces apoptosis at least equivalent to that caused by DNA damage. Immunoprecipitation assays confirm HOPS binding to p53-mutant forms. The interaction of HOPS/TMUB1 with p53-mutants strengthens its effect on the apoptotic cascade, showing a context-dependent gain or loss of function. Gene expression analysis of the MYC and TP63 genes shows that H1975 exhibit a gain-of-function profile, while SKBR3 promote apoptosis in a TP63-dependent manner. The TCGA data further corroborate HOPS/TMUB1's positive correlation with apoptotic genes BAX, BBC3, and NOXA1, underscoring its relevance in patient samples. Notably, singular TP53 mutations inadequately explain pathway dysregulation, emphasizing the need to explore additional contributing factors. These findings illuminate the intricate interplay among TP53 mutations, HOPS/TMUB1, and apoptotic pathways, providing valuable insights for targeted cancer interventions.


Apoptosis , Mutation , Neoplasms , Tumor Suppressor Protein p53 , Humans , Apoptosis/genetics , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Cell Line, Tumor , Neoplasms/genetics , Neoplasms/pathology , Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Transcription Factors
5.
PLoS One ; 19(5): e0303314, 2024.
Article En | MEDLINE | ID: mdl-38739668

BACKGROUND: Globally, hepatocellular carcinoma (HCC) is the second most common cause of cancer-related death due to a lack of early predictive and/or diagnostic tools. Thus, research for a new biomarker is important. LncRNAs play a functional role in target gene regulation and their deregulation is associated with several pathological conditions including HCC. OBJECTIVE: This study aimed to explore the diagnostic potential of two LncRNAs MALAT1 and CASC2 in HCC compared to the routinely used diagnostic biomarker. MATERIALS AND METHODS: The current study is a case-control study carried out at Fayoum University Hospital and conducted on 89 individuals. The study included three groups of 36 HCC patients on top of HCV(HCC/HCV), 33 HCV patients, and 20 healthy volunteers as a control group. All study subjects were subjected to radiological examinations. The determination of CBC was performed by the automated counter and liver function tests by the enzymatic method were performed. In addition, HCV RNA quantification and the expression level of two LncRNAs (MALAT1 and CASC2) were performed by qRT-PCR. RESULTS: The results revealed a statistically significant difference between study groups regarding liver function tests with a higher mean in HCC/HCV group. Also, serum MALAT1 significantly up-regulated in HCV (11.2±2.8) and HCC/HCV (4.56±1.4) compared to the control group. Besides, serum CASC2 levels in the HCV group were significantly upregulated (14.9±3.6), while, downregulated in the HCC group (0.16± 0.03). Furthermore, The ROC analysis for diagnostic efficacy parameters indicated that CASC2 has higher accuracy (94.6%) and sensitivity (97.2%) for HCC diagnosis than AFP with an accuracy of (90.9%), sensitivity (69.4%), and MALAT1 showed an accuracy of (56.9%), sensitivity (72.2%). CONCLUSION: Our study results indicated that CASC2 is a promising biomarker and is considered better and could help in HCC diagnosis on top of HCV than MALAT1 and the routine biomarker AFP.


Biomarkers, Tumor , Carcinoma, Hepatocellular , Liver Neoplasms , RNA, Long Noncoding , Tumor Suppressor Proteins , Humans , RNA, Long Noncoding/genetics , RNA, Long Noncoding/blood , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/virology , Liver Neoplasms/diagnosis , Liver Neoplasms/genetics , Liver Neoplasms/virology , Male , Female , Middle Aged , Case-Control Studies , Biomarkers, Tumor/genetics , Biomarkers, Tumor/blood , Tumor Suppressor Proteins/genetics , Hepatitis C/complications , Hepatitis C/virology , Hepatitis C/diagnosis , Hepatitis C/genetics , Hepacivirus/genetics , Aged , Gene Expression Regulation, Neoplastic , Adult , ROC Curve , Clinical Relevance
6.
BMC Cancer ; 24(1): 587, 2024 May 14.
Article En | MEDLINE | ID: mdl-38741073

YAP and TAZ, the Hippo pathway terminal transcriptional activators, are frequently upregulated in cancers. In tumor cells, they have been mainly associated with increased tumorigenesis controlling different aspects from cell cycle regulation, stemness, or resistance to chemotherapies. In fewer cases, they have also been shown to oppose cancer progression, including by promoting cell death through the action of the p73/YAP transcriptional complex, in particular after chemotherapeutic drug exposure. Using HCT116 cells, we show here that oxaliplatin treatment led to core Hippo pathway down-regulation and nuclear accumulation of TAZ. We further show that TAZ was required for the increased sensitivity of HCT116 cells to oxaliplatin, an effect that appeared independent of p73, but which required the nuclear relocalization of TAZ. Accordingly, Verteporfin and CA3, two drugs affecting the activity of YAP and TAZ, showed antagonistic effects with oxaliplatin in co-treatments. Importantly, using several colorectal cell lines, we show that the sensitizing action of TAZ to oxaliplatin is dependent on the p53 status of the cells. Our results support thus an early action of TAZ to sensitize cells to oxaliplatin, consistent with a model in which nuclear TAZ in the context of DNA damage and p53 activity pushes cells towards apoptosis.


Antineoplastic Agents , Colonic Neoplasms , Hippo Signaling Pathway , Organoplatinum Compounds , Oxaliplatin , Protein Serine-Threonine Kinases , Signal Transduction , Trans-Activators , Transcription Factors , Transcriptional Coactivator with PDZ-Binding Motif Proteins , Tumor Suppressor Protein p53 , Humans , Oxaliplatin/pharmacology , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics , Colonic Neoplasms/drug therapy , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Colonic Neoplasms/genetics , Trans-Activators/metabolism , Trans-Activators/genetics , Transcription Factors/metabolism , Transcription Factors/genetics , HCT116 Cells , Signal Transduction/drug effects , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Organoplatinum Compounds/pharmacology , Organoplatinum Compounds/therapeutic use , Antineoplastic Agents/pharmacology , Intracellular Signaling Peptides and Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Drug Resistance, Neoplasm/genetics , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Verteporfin/pharmacology , Verteporfin/therapeutic use , Cell Line, Tumor , Tumor Protein p73/metabolism , Tumor Protein p73/genetics , YAP-Signaling Proteins/metabolism , Porphyrins/pharmacology , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , Gene Expression Regulation, Neoplastic/drug effects , Apoptosis/drug effects
7.
Proc Natl Acad Sci U S A ; 121(20): e2402180121, 2024 May 14.
Article En | MEDLINE | ID: mdl-38717859

Membrane tubulation coupled with fission (MTCF) is a widespread phenomenon but mechanisms for their coordination remain unclear, partly because of the lack of assays to monitor dynamics of membrane tubulation and subsequent fission. Using polymer cushioned bilayer islands, we analyze the membrane tubulator Bridging Integrator 1 (BIN1) mixed with the fission catalyst dynamin2 (Dyn2). Our results reveal this mixture to constitute a minimal two-component module that demonstrates MTCF. MTCF is an emergent property and arises because BIN1 facilitates recruitment but inhibits membrane binding of Dyn2 in a dose-dependent manner. MTCF is therefore apparent only at high Dyn2 to BIN1 ratios. Because of their mutual involvement in T-tubules biogenesis, mutations in BIN1 and Dyn2 are associated with centronuclear myopathies and our analysis links the pathology with aberrant MTCF. Together, our results establish cushioned bilayer islands as a facile template for the analysis of membrane tubulation and inform of mechanisms that coordinate MTCF.


Adaptor Proteins, Signal Transducing , Dynamin II , Tumor Suppressor Proteins , Dynamin II/metabolism , Dynamin II/genetics , Humans , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Cell Membrane/metabolism , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Mitochondrial Dynamics/physiology , Myopathies, Structural, Congenital/genetics , Myopathies, Structural, Congenital/metabolism
8.
FASEB J ; 38(9): e23633, 2024 May 15.
Article En | MEDLINE | ID: mdl-38690712

Recent reports suggest that the Hippo signaling pathway regulates testis development, though its exact roles in Sertoli cell differentiation remain unknown. Here, we examined the functions of the main Hippo pathway kinases, large tumor suppressor homolog kinases 1 and 2 (Lats1 and Lats2) in developing mouse Sertoli cells. Conditional inactivation of Lats1/2 in Sertoli cells resulted in the disorganization and overgrowth of the testis cords, the induction of a testicular inflammatory response and germ cell apoptosis. Stimulated by retinoic acid 8 (STRA8) expression in germ cells additionally suggested that germ cells may have been preparing to enter meiosis prior to their loss. Gene expression analyses of the developing testes of conditional knockout animals further suggested impaired Sertoli cell differentiation, epithelial-to-mesenchymal transition, and the induction of a specific set of genes associated with Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ)-mediated integrin signaling. Finally, the involvement of YAP/TAZ in Sertoli cell differentiation was confirmed by concomitantly inactivating Yap/Taz in Lats1/2 conditional knockout model, which resulted in a partial rescue of the testicular phenotypic changes. Taken together, these results identify Hippo signaling as a crucial pathway for Sertoli cell development and provide novel insight into Sertoli cell fate maintenance.


Adaptor Proteins, Signal Transducing , Cell Differentiation , Protein Serine-Threonine Kinases , Sertoli Cells , Tumor Suppressor Proteins , YAP-Signaling Proteins , Animals , Sertoli Cells/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Male , Mice , YAP-Signaling Proteins/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Cell Differentiation/physiology , Mice, Knockout , Signal Transduction , Cell Cycle Proteins/metabolism , Cell Cycle Proteins/genetics , Testis/metabolism , Epithelial-Mesenchymal Transition/physiology , Transcription Factors/metabolism , Transcription Factors/genetics , Acyltransferases/genetics , Acyltransferases/metabolism , Transcriptional Coactivator with PDZ-Binding Motif Proteins/metabolism , Trans-Activators/metabolism , Trans-Activators/genetics
9.
J Clin Invest ; 134(9)2024 Mar 12.
Article En | MEDLINE | ID: mdl-38690732

Epigenetic regulatory mechanisms are underappreciated, yet are critical for enteric nervous system (ENS) development and maintenance. We discovered that fetal loss of the epigenetic regulator Bap1 in the ENS lineage caused severe postnatal bowel dysfunction and early death in Tyrosinase-Cre Bap1fl/fl mice. Bap1-depleted ENS appeared normal in neonates; however, by P15, Bap1-deficient enteric neurons were largely absent from the small and large intestine of Tyrosinase-Cre Bap1fl/fl mice. Bowel motility became markedly abnormal with disproportionate loss of cholinergic neurons. Single-cell RNA sequencing at P5 showed that fetal Bap1 loss in Tyrosinase-Cre Bap1fl/fl mice markedly altered the composition and relative proportions of enteric neuron subtypes. In contrast, postnatal deletion of Bap1 did not cause enteric neuron loss or impaired bowel motility. These findings suggest that BAP1 is critical for postnatal enteric neuron differentiation and for early enteric neuron survival, a finding that may be relevant to the recently described human BAP1-associated neurodevelopmental disorder.


Cell Differentiation , Enteric Nervous System , Tumor Suppressor Proteins , Ubiquitin Thiolesterase , Animals , Enteric Nervous System/metabolism , Enteric Nervous System/pathology , Mice , Ubiquitin Thiolesterase/genetics , Ubiquitin Thiolesterase/metabolism , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Neurons/metabolism , Neurons/pathology , Mice, Knockout , Female , Gastrointestinal Motility/genetics , Humans
10.
Proc Natl Acad Sci U S A ; 121(21): e2318591121, 2024 May 21.
Article En | MEDLINE | ID: mdl-38739802

The transcription factor p73, a member of the p53 tumor-suppressor family, regulates cell death and also supports tumorigenesis, although the mechanistic basis for the dichotomous functions is poorly understood. We report here the identification of an alternate transactivation domain (TAD) located at the extreme carboxyl (C) terminus of TAp73ß, a commonly expressed p73 isoform. Mutational disruption of this TAD significantly reduced TAp73ß's transactivation activity, to a level observed when the amino (N)-TAD that is similar to p53's TAD, is mutated. Mutation of both TADs almost completely abolished TAp73ß's transactivation activity. Expression profiling highlighted a unique set of targets involved in extracellular matrix-receptor interaction and focal adhesion regulated by the C-TAD, resulting in FAK phosphorylation, distinct from the N-TAD targets that are common to p53 and are involved in growth inhibition. Interestingly, the C-TAD targets are also regulated by the oncogenic, amino-terminal-deficient DNp73ß isoform. Consistently, mutation of C-TAD reduces cellular migration and proliferation. Mechanistically, selective binding of TAp73ß to DNAJA1 is required for the transactivation of C-TAD target genes, and silencing DNAJA1 expression abrogated all C-TAD-mediated effects. Taken together, our results provide a mechanistic basis for the dichotomous functions of TAp73 in the regulation of cellular growth through its distinct TADs.


Cell Proliferation , Protein Domains , Transcriptional Activation , Tumor Protein p73 , Tumor Protein p73/metabolism , Tumor Protein p73/genetics , Humans , Cell Movement/genetics , Mutation , Cell Line, Tumor , Protein Isoforms/metabolism , Protein Isoforms/genetics , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics , Phosphorylation , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics
11.
Neurosciences (Riyadh) ; 29(2): 113-121, 2024 May.
Article En | MEDLINE | ID: mdl-38740395

OBJECTIVES: To determine the prevalence of tuberous sclerosis complex (TSC) in the paediatric Saudi population and to characterise the range of clinical symptoms, neurocutaneous findings, neuroimaging results, and complications of the disease. METHODS: A total of 61 genetically confirmed TSC patients from the National Guard Health Affairs (NGHA) in Saudi Arabia were the subject of this retrospective descriptive analysis. The data were presented using descriptive measures. RESULTS: The mean age at diagnosis was found to be 4.9 years. Subependymal nodules (86.9%), numerous cortical tubers and/or radial migration lines (63.9%), and hypomelanotic macules (63.9%) were the 3 most common significant criteria. The vast majority (86.9%) of those diagnosed had epilepsy, of which 50% were considered medically intractable. Nearly half of our subjects underwent genetic testing, which revealed that TSC2 predominated over TSC1. Symptoms of Tuberous Sclerosis Complex-Associated Neuropsychiatric Disorders (TAND) were present in 66.7% of TSC1 patients and 73.9% of TSC2 patients. CONCLUSION: The findings of this study demonstrate that the clinical spectrum of TSC among Saudi children is consistent with the body of existing literature. The TSC2 was more prevalent than TSC1. The most frequent signs were cutaneous and neurological. Monitoring TSC patients regularly is crucial to identify any issues as soon as possible.


Tuberous Sclerosis Complex 2 Protein , Tuberous Sclerosis , Humans , Tuberous Sclerosis/epidemiology , Tuberous Sclerosis/complications , Saudi Arabia/epidemiology , Female , Male , Child, Preschool , Child , Tuberous Sclerosis Complex 2 Protein/genetics , Retrospective Studies , Infant , Adolescent , Tuberous Sclerosis Complex 1 Protein/genetics , Tumor Suppressor Proteins/genetics , Epilepsy/epidemiology , Epilepsy/etiology , Prevalence
12.
PLoS One ; 19(5): e0302926, 2024.
Article En | MEDLINE | ID: mdl-38718095

Zinc Finger MIZ-Type Containing 1 (Zmiz1), also known as ZIMP10 or RAI17, is a transcription cofactor and member of the Protein Inhibitor of Activated STAT (PIAS) family of proteins. Zmiz1 is critical for a variety of biological processes including vascular development. However, its role in the lymphatic vasculature is unknown. In this study, we utilized human dermal lymphatic endothelial cells (HDLECs) and an inducible, lymphatic endothelial cell (LEC)-specific Zmiz1 knockout mouse model to investigate the role of Zmiz1 in LECs. Transcriptional profiling of ZMIZ1-deficient HDLECs revealed downregulation of genes crucial for lymphatic vessel development. Additionally, our findings demonstrated that loss of Zmiz1 results in reduced expression of proliferation and migration genes in HDLECs and reduced proliferation and migration in vitro. We also presented evidence that Zmiz1 regulates Prox1 expression in vitro and in vivo by modulating chromatin accessibility at Prox1 regulatory regions. Furthermore, we observed that loss of Zmiz1 in mesenteric lymphatic vessels significantly reduced valve density. Collectively, our results highlight a novel role of Zmiz1 in LECs and as a transcriptional regulator of Prox1, shedding light on a previously unknown regulatory factor in lymphatic vascular biology.


Cell Proliferation , Endothelial Cells , Homeodomain Proteins , Lymphatic Vessels , Mice, Knockout , Transcription Factors , Tumor Suppressor Proteins , Animals , Endothelial Cells/metabolism , Humans , Mice , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Lymphatic Vessels/metabolism , Lymphatic Vessels/cytology , Cell Movement/genetics , Gene Expression Regulation , Lymphangiogenesis/genetics
13.
Development ; 151(9)2024 May 01.
Article En | MEDLINE | ID: mdl-38722096

During embryonic development, lymphatic endothelial cell (LEC) precursors are distinguished from blood endothelial cells by the expression of Prospero-related homeobox 1 (Prox1), which is essential for lymphatic vasculature formation in mouse and zebrafish. Prox1 expression initiation precedes LEC sprouting and migration, serving as the marker of specified LECs. Despite its crucial role in lymphatic development, Prox1 upstream regulation in LECs remains to be uncovered. SOX18 and COUP-TFII are thought to regulate Prox1 in mice by binding its promoter region. However, the specific regulation of Prox1 expression in LECs remains to be studied in detail. Here, we used evolutionary conservation and chromatin accessibility to identify enhancers located in the proximity of zebrafish prox1a active in developing LECs. We confirmed the functional role of the identified sequences through CRISPR/Cas9 mutagenesis of a lymphatic valve enhancer. The deletion of this region results in impaired valve morphology and function. Overall, our results reveal an intricate control of prox1a expression through a collection of enhancers. Ray-finned fish-specific distal enhancers drive pan-lymphatic expression, whereas vertebrate-conserved proximal enhancers refine expression in functionally distinct subsets of lymphatic endothelium.


Endothelial Cells , Enhancer Elements, Genetic , Gene Expression Regulation, Developmental , Homeodomain Proteins , Lymphatic Vessels , Tumor Suppressor Proteins , Zebrafish Proteins , Zebrafish , Animals , Homeodomain Proteins/metabolism , Homeodomain Proteins/genetics , Zebrafish/genetics , Zebrafish/embryology , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Enhancer Elements, Genetic/genetics , Lymphatic Vessels/metabolism , Lymphatic Vessels/embryology , Zebrafish Proteins/metabolism , Zebrafish Proteins/genetics , Endothelial Cells/metabolism , Lymphangiogenesis/genetics , CRISPR-Cas Systems/genetics , Promoter Regions, Genetic/genetics , Mice
14.
CNS Neurosci Ther ; 30(4): e14711, 2024 04.
Article En | MEDLINE | ID: mdl-38644551

OBJECTIVE: To elucidate the relationship between USP19 and O(6)-methylguanine-DNA methyltransferase (MGMT) after temozolomide treatment in glioblastoma (GBM) patients with chemotherapy resistance. METHODS: Screening the deubiquitinase pannel and identifying the deubiquitinase directly interacts with and deubiquitination MGMT. Deubiquitination assay to confirm USP19 deubiquitinates MGMT. The colony formation and tumor growth study in xenograft assess USP19 affects the GBM sensitive to TMZ was performed by T98G, LN18, U251, and U87 cell lines. Immunohistochemistry staining and survival analysis were performed to explore how USP19 is correlated to MGMT in GBM clinical management. RESULTS: USP19 removes the ubiquitination of MGMT to facilitate the DNA methylation damage repair. Depletion of USP19 results in the glioblastoma cell sensitivity to temozolomide, which can be rescued by overexpressing MGMT. USP19 is overexpressed in glioblastoma patient samples, which positively correlates with the level of MGMT protein and poor prognosis in these patients. CONCLUSION: The regulation of MGMT ubiquitination by USP19 plays a critical role in DNA methylation damage repair and GBM patients' temozolomide chemotherapy response.


Antineoplastic Agents, Alkylating , DNA Methylation , DNA Modification Methylases , DNA Repair Enzymes , Drug Resistance, Neoplasm , Temozolomide , Tumor Suppressor Proteins , Humans , Temozolomide/pharmacology , Temozolomide/therapeutic use , DNA Repair Enzymes/metabolism , DNA Repair Enzymes/genetics , DNA Modification Methylases/metabolism , Antineoplastic Agents, Alkylating/pharmacology , Antineoplastic Agents, Alkylating/therapeutic use , Animals , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , DNA Methylation/drug effects , Mice, Nude , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Glioblastoma/drug therapy , Glioblastoma/genetics , Glioblastoma/metabolism , Mice , Male , Female , Dacarbazine/analogs & derivatives , Dacarbazine/pharmacology , Dacarbazine/therapeutic use , DNA Repair/drug effects , Endopeptidases/metabolism , Endopeptidases/genetics , Xenograft Model Antitumor Assays , Ubiquitination/drug effects
15.
Appl Immunohistochem Mol Morphol ; 32(5): 249-253, 2024.
Article En | MEDLINE | ID: mdl-38602289

The pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) family has been found to have both tumor-suppressor and oncogenic properties across various types and locations of cancer. Given that PHLPP has not been previously studied in oral squamous cell carcinoma (SCC), we conducted an assessment of the expression of both its isoforms in oral SCC tissues and cell lines and compared these findings to their corresponding normal counterparts. In addition, we assessed the relationship between PHLPP and clinicopathological factors and patient survival. Quantitative real-time polymerase chain reaction was used to detect the mRNA levels of PHLPP1 and PHLPP2 in cancerous and normal cell lines in addition to 124 oral SCC and noncancerous adjacent epithelia (N = 62, each). Correlations between their expression rate and clinicopathological parameters were further evaluated in 57 patients. Data were statistically analyzed with t test and paired t test, analysis of variance, Mann-Whitney U , and Cox Regression tests ( P < 0.05). We found significantly lower levels of both PHLPP isoforms in oral SCC tissues compared with noncancerous epithelia ( P < 0.001, for both). However, in the cell lines, this difference was significant only for PHLPP1 ( P = 0.027). The correlation between the two isoforms was significant only in cancerous tissues ( P < 0.001). None of the clinicopathologic factors showed significant associations with either of the isoforms and there was no correlation with survival. We showed for the first time that PHLPP1 and PHLPP2 act as tumor suppressors in oral SCC at the mRNA level. The regulation of their mRNA appears to be different between normal and cancerous tissues.


Carcinoma, Squamous Cell , Mouth Neoplasms , Nuclear Proteins , Phosphoprotein Phosphatases , Humans , Phosphoprotein Phosphatases/metabolism , Phosphoprotein Phosphatases/genetics , Mouth Neoplasms/pathology , Mouth Neoplasms/genetics , Mouth Neoplasms/metabolism , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/metabolism , Female , Male , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Middle Aged , Cell Line, Tumor , Aged , Gene Expression Regulation, Neoplastic , Adult , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Protein Isoforms/metabolism
16.
J Cancer Res Clin Oncol ; 150(4): 204, 2024 Apr 20.
Article En | MEDLINE | ID: mdl-38642144

BACKGROUND: Emerging research has validated that circular RNAs (circRNAs) have indispensable regulatory functions in tumorigenesis, including colorectal cancer (CRC). Ferroptosis is a specific cell death form and implicates in the malignant progression of tumors. Here, this study aimed to investigate the biofunction of circ_0087851 in tumor progression and ferroptosis of CRC, as well as its underlying molecular mechanism. METHODS: The expression pattern of circ_0087851 in CRC was validated by qRT-PCR. The biological characteristics of circ_0087851 in CRC were assessed through CCK-8, colony formation and transwell assays in vitro. The ferroptosis was measured using ferroptosis-related reagents on iron, Fe2+, and lipid ROS detection. Bioinformatics, luciferase reporter, and RNA pulldown assays were employed to reveal the circ_0087851-mediated regulatory network. In addition, the effect of circ_0087851 on tumor growth in vivo was detected using a xenograft model. RESULTS: Circ_0087851 was notably diminished in CRC tissues and cells. Functionally, overexpression of circ_0087851 suppressed CRC cell growth, migration, invasion, and facilitated ferroptosis in vitro. Meanwhile, circ_0087851 upregulation impeded CRC growth in vivo. Mechanistically, circ_0087851 functioned as a molecular sponge for miR-593-3p, and BRCA1 associated protein 1 (BAP1) was identified as a downstream target of miR-593-3p. Besides, rescue experiments revealed that miR-593-3p overexpression or silencing of BAP1 reversed circ_0087851-mediated CRC progression. CONCLUSION: Circ_0087851 performed as a tumor suppressor and ferroptosis promoter by the miR-593-3p/BAP1 axis, providing novel biomarker and therapeutic target for the clinical management of CRC.


Colorectal Neoplasms , Ferroptosis , MicroRNAs , RNA, Circular , Humans , Carcinogenesis , Cell Line, Tumor , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Ferroptosis/genetics , MicroRNAs/genetics , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Ubiquitin Thiolesterase/genetics , Ubiquitin Thiolesterase/metabolism , RNA, Circular/genetics
17.
Environ Int ; 186: 108645, 2024 Apr.
Article En | MEDLINE | ID: mdl-38615541

Benzene is a broadly used industrial chemicals which causes various hematologic abnormalities in human. Altered DNA methylation has been proposed as epigenetic biomarkers in health risk evaluation of benzene exposure, yet the role of methylation at specific CpG sites in predicting hematological effects remains unclear. In this study, we recruited 120 low-level benzene-exposed and 101 control male workers from a petrochemical factory in Maoming City, Guangdong Province, China. Urinary S-phenylmercapturic acid (SPMA) in benzene-exposed workers was 3.40-fold higher than that in control workers (P < 0.001). Benzene-induced hematotoxicity was characterized by reduced white blood cells counts and nuclear division index (NDI), along with an increased DNA damage and urinary 8-hydroxy-2'-deoxyguanosine (all P < 0.05). Methylation levels of TRIM36, MGMT and RASSF1a genes in peripheral blood lymphocytes (PBLCs) were quantified by pyrosequencing. CpG site 6 of TRIM36, CpG site 2, 4, 6 of RASSF1a and CpG site 1, 3 of MGMT methylation were recognized as hot CpG sites due to a strong correlation with both internal exposure and hematological effects. Notably, integrating hot CpG sites methylation of multiple genes reveal a higher efficiency in prediction of integrative damage compared to individual genes at hot CpG sites. The negative dose-response relationship between the combined methylation of hot CpG sites in three genes and integrative damage enabled the classification of benzene-exposed individuals into high-risk or low-risk groups using the median cut-off value of the integrative index. Subsequently, a prediction model for integrative damage in benzene-exposed populations was built based on the methylation status of the identified hot CpG sites in the three genes. Taken together, these findings provide a novel insight into application prospect of specific CpG site methylation as epi-biomarkers for health risk assessment of environmental pollutants.


Acetylcysteine/analogs & derivatives , Benzene , CpG Islands , DNA Methylation , Occupational Exposure , Humans , DNA Methylation/drug effects , Male , Occupational Exposure/adverse effects , Benzene/toxicity , Adult , China , DNA Damage , Middle Aged , Biomarkers/urine , Acetylcysteine/urine , Tumor Suppressor Proteins/genetics , DNA Repair Enzymes/genetics
18.
J Cell Mol Med ; 28(8): e18216, 2024 Apr.
Article En | MEDLINE | ID: mdl-38652219

We tried to elucidate the possible roles of maternal embryonic leucine pull chain kinase (MELK) in lung adenocarcinoma (LUAD) growth and metastasis. Differentially expressed genes in LUAD samples were analysed by the GEPIA database. Clinical tissue samples and cells were collected for MELK, EZH2 and LATS2 expression determination. Co-IP assay was used to verify the interaction between EZH2 and MELK; CHX tracking assay and ubiquitination assay detected the degradation of MELK on EZH2 ubiquitination. ChIP assay detected the enrichment of EZH2 and H3K27me3 on the LATS2 promoter region. LUAD cells were selected for in vitro validation, and the tumorigenic ability of LUAD cells was also observed in a transplantation tumour model of LUAD nude mice. MELK and EZH2 were highly expressed in LUAD samples, while LATS2 was lowly expressed. MELK interacted with EZH2 to inhibit its ubiquitination degradation; EZH2 elevated H3K27me3 modification in the LATS2 promoter to lower LATS2 expression. Silencing MELK or EZH2 or overexpressing LATS2 restrained LUAD cell proliferation and invasion, and facilitated their apoptosis. Silencing MELK or EZH2 or overexpressing LATS2 suppressed tumour formation in nude mice. This study demonstrated that MELK aggravated LUAD by upregulating EZH2 and downregulating LATS2.


Adenocarcinoma of Lung , Cell Proliferation , Enhancer of Zeste Homolog 2 Protein , Gene Expression Regulation, Neoplastic , Histones , Lung Neoplasms , Mice, Nude , Protein Serine-Threonine Kinases , Tumor Suppressor Proteins , Ubiquitination , Humans , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Animals , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/pathology , Adenocarcinoma of Lung/metabolism , Enhancer of Zeste Homolog 2 Protein/metabolism , Enhancer of Zeste Homolog 2 Protein/genetics , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , Histones/metabolism , Mice , Cell Proliferation/genetics , Methylation , Cell Line, Tumor , Promoter Regions, Genetic/genetics , Apoptosis/genetics , Female , Male
19.
Nat Immunol ; 25(5): 860-872, 2024 May.
Article En | MEDLINE | ID: mdl-38632339

Adaptive immunity relies on specialized effector functions elicited by lymphocytes, yet how antigen recognition activates appropriate effector responses through nonspecific signaling intermediates is unclear. Here we examined the role of chromatin priming in specifying the functional outputs of effector T cells and found that most of the cis-regulatory landscape active in effector T cells was poised early in development before the expression of the T cell antigen receptor. We identified two principal mechanisms underpinning this poised landscape: the recruitment of the nucleosome remodeler mammalian SWItch/Sucrose Non-Fermentable (mSWI/SNF) by the transcription factors RUNX1 and PU.1 to establish chromatin accessibility at T effector loci; and a 'relay' whereby the transcription factor BCL11B succeeded PU.1 to maintain occupancy of the chromatin remodeling complex mSWI/SNF together with RUNX1, after PU.1 silencing during lineage commitment. These mechanisms define modes by which T cells acquire the potential to elicit specialized effector functions early in their ontogeny and underscore the importance of integrating extrinsic cues to the developmentally specified intrinsic program.


Core Binding Factor Alpha 2 Subunit , Proto-Oncogene Proteins , Repressor Proteins , Trans-Activators , Transcription Factors , Tumor Suppressor Proteins , Proto-Oncogene Proteins/metabolism , Animals , Trans-Activators/metabolism , Trans-Activators/genetics , Mice , Core Binding Factor Alpha 2 Subunit/metabolism , Core Binding Factor Alpha 2 Subunit/genetics , Repressor Proteins/metabolism , Repressor Proteins/genetics , Transcription Factors/metabolism , Transcription Factors/genetics , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/genetics , Mice, Inbred C57BL , Chromosomal Proteins, Non-Histone/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Mice, Knockout , Chromatin Assembly and Disassembly , Cell Differentiation/immunology
20.
Int J Mol Sci ; 25(7)2024 Apr 06.
Article En | MEDLINE | ID: mdl-38612892

Glioblastoma (GBM) is a fatal brain tumor with limited treatment options. O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation status is the central molecular biomarker linked to both the response to temozolomide, the standard chemotherapy drug employed for GBM, and to patient survival. However, MGMT status is captured on tumor tissue which, given the difficulty in acquisition, limits the use of this molecular feature for treatment monitoring. MGMT protein expression levels may offer additional insights into the mechanistic understanding of MGMT but, currently, they correlate poorly to promoter methylation. The difficulty of acquiring tumor tissue for MGMT testing drives the need for non-invasive methods to predict MGMT status. Feature selection aims to identify the most informative features to build accurate and interpretable prediction models. This study explores the new application of a combined feature selection (i.e., LASSO and mRMR) and the rank-based weighting method (i.e., MGMT ProFWise) to non-invasively link MGMT promoter methylation status and serum protein expression in patients with GBM. Our method provides promising results, reducing dimensionality (by more than 95%) when employed on two large-scale proteomic datasets (7k SomaScan® panel and CPTAC) for all our analyses. The computational results indicate that the proposed approach provides 14 shared serum biomarkers that may be helpful for diagnostic, prognostic, and/or predictive operations for GBM-related processes, given further validation.


Brain Neoplasms , Glioblastoma , Humans , Glioblastoma/genetics , Proteomics , Temozolomide/therapeutic use , Blood Proteins , Brain Neoplasms/genetics , O(6)-Methylguanine-DNA Methyltransferase , DNA Modification Methylases/genetics , Tumor Suppressor Proteins/genetics , DNA Repair Enzymes/genetics
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