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2.
Vopr Virusol ; 69(2): 127-133, 2024 May 06.
Article En | MEDLINE | ID: mdl-38843019

OBJECTIVES: The HTLV-1 infection persists for life, remaining as asymptomatic viral reservoirs in most patients, ensuring the chain of transmission, but around 4% develop adult T-cell leukemia/lymphoma (ATLL). HTLV-1 is an oncogenic retrovirus that transforms CD4+ T lymphocytes and deregulates the lymphoproliferative pathways that contribute to the development of ATLL. To achieve cell transformation, most oncogenic retroviruses use proto-oncogene capture transduction, with proviral integration disrupting the expression of tumor suppressors or proto-oncogenes. THE AIM: We conducted this study on the prevalence of HTLV-1 infection in blood donors to expand the HTLV-1 database, assess the risk of transmission via blood products, as well as evaluate the risk of persistent infection or development of neoplastic diseases in HTLV-1 carriers. MATERIALS AND METHODS: This is a cross-sectional study of blood donors of all categories. For this study, 265 blood donors were recruited at the Centre National de Transfusion Sanguine in Brazzaville. After testing for HTLV-1 antibodies by ELISA, proviral DNA was extracted from all ELISA-positive samples for detection by nested PCR, followed by RT qPCR using specific primers p53 and c-myc for gene expression. RESULTS: 20/265 were positive for anti-HTLV-1 antibody, 5 donors were positive for proviral DNA. The prevalence of HTLV-1 was 1.8%. All HTLV-1-positive donors were male (1.8%), with a positive correlation (p = 0.05); the 1.1% of positive donors were regular, with the majority aged between 31 and 45 years (1.5%), and concubine donors were the most frequent (1.1%). All samples showed normal expression of the p53 and c-myc genes. CONCLUSION: The prevalence, though low, remains a serious problem. No abnormal p53 or c-myc gene expression was detected in HTLV-1-positive donors, which could mean that none of the T lymphocytes in these donors had been transformed by HTLV-1.


Blood Donors , HTLV-I Infections , Human T-lymphotropic virus 1 , Proto-Oncogene Proteins c-myc , Tumor Suppressor Protein p53 , Humans , Human T-lymphotropic virus 1/genetics , Male , HTLV-I Infections/epidemiology , HTLV-I Infections/virology , HTLV-I Infections/genetics , HTLV-I Infections/blood , Adult , Female , Tumor Suppressor Protein p53/genetics , Middle Aged , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Mas , Cross-Sectional Studies , Gene Expression Profiling , Leukemia-Lymphoma, Adult T-Cell/virology , Leukemia-Lymphoma, Adult T-Cell/epidemiology , Leukemia-Lymphoma, Adult T-Cell/genetics , Leukemia-Lymphoma, Adult T-Cell/blood , Proviruses/genetics , Adolescent
3.
Cell Death Dis ; 15(6): 427, 2024 Jun 18.
Article En | MEDLINE | ID: mdl-38890303

As the second most common malignant tumor in the urinary system, renal cell carcinoma (RCC) is imperative to explore its early diagnostic markers and therapeutic targets. Numerous studies have shown that AURKB promotes tumor development by phosphorylating downstream substrates. However, the functional effects and regulatory mechanisms of AURKB on clear cell renal cell carcinoma (ccRCC) progression remain largely unknown. In the current study, we identified AURKB as a novel key gene in ccRCC progression based on bioinformatics analysis. Meanwhile, we observed that AURKB was highly expressed in ccRCC tissue and cell lines and knockdown AURKB in ccRCC cells inhibit cell proliferation and migration in vitro and in vivo. Identified CDC37 as a kinase molecular chaperone for AURKB, which phenocopy AURKB in ccRCC. AURKB/CDC37 complex mediate the stabilization of MYC protein by directly phosphorylating MYC at S67 and S373 to promote ccRCC development. At the same time, we demonstrated that the AURKB/CDC37 complex activates MYC to transcribe CCND1, enhances Rb phosphorylation, and promotes E2F1 release, which in turn activates AURKB transcription and forms a positive feedforward loop in ccRCC. Collectively, our study identified AURKB as a novel marker of ccRCC, revealed a new mechanism by which the AURKB/CDC37 complex promotes ccRCC by directly phosphorylating MYC to enhance its stability, and first proposed AURKB/E2F1-positive feedforward loop, highlighting AURKB may be a promising therapeutic target for ccRCC.


Aurora Kinase B , Carcinoma, Renal Cell , Cell Cycle Proteins , Disease Progression , E2F1 Transcription Factor , Kidney Neoplasms , Proto-Oncogene Proteins c-myc , Humans , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/metabolism , E2F1 Transcription Factor/metabolism , E2F1 Transcription Factor/genetics , Kidney Neoplasms/pathology , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , Cell Cycle Proteins/metabolism , Cell Cycle Proteins/genetics , Cell Line, Tumor , Phosphorylation , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Aurora Kinase B/metabolism , Aurora Kinase B/genetics , Cell Proliferation , Animals , Gene Expression Regulation, Neoplastic , Mice, Nude , Mice , Cell Movement/genetics , Chaperonins
4.
Front Immunol ; 15: 1393906, 2024.
Article En | MEDLINE | ID: mdl-38911853

Infections are common in plasma cell cancer multiple myeloma (MM) due to disease-related immune deficiencies and cancer treatment. Myeloma cells express Toll-like receptors (TLRs), and TLR activation has been shown to induce proliferative and pro-survival signals in cancer cells. MM is a complex and heterogeneous disease, and expression levels of TLRs as well as downstream signaling components are likely to differ between patients. Here, we show that in a large cohort of patients, TLR1, TLR4, TLR6, TLR9, and TLR10 are the most highly expressed in primary CD138+ cells. Using an MM cell line expressing TLR4 and TLR9 as a model, we demonstrate that TLR4 and TLR9 activation promoted the expression of well-established pro-survival and oncogenes in MM such as MYC, IRF4, NFKB, and BCL2. TLR4 and TLR9 activation inhibited the efficacy of proteasome inhibitors bortezomib and carfilzomib, drugs used in the treatment of MM. Inhibiting the autophagosome-lysosome protein degradation pathway by hydroxychloroquine (HCQ) diminished the protective effect of TLR activation on proteasome inhibitor-induced cytotoxicity. We also found that TLR signaling downregulated the expression of TNFRSF17, the gene encoding for B-cell maturation antigen (BCMA). MYC, BCL2, and BCL2L1 were upregulated in approximately 50% of primary cells, while the response to TLR signaling in terms of TNFRSF17 expression was dichotomous, as an equal fraction of patients showed upregulation and downregulation of the gene. While proteasome inhibitors are part of first-line MM treatment, several of the new anti-MM immune therapeutic drugs target BCMA. Thus, TLR activation may render MM cells less responsive to commonly used anti-myeloma drugs.


B-Cell Maturation Antigen , Gene Expression Regulation, Neoplastic , Multiple Myeloma , Proto-Oncogene Proteins c-myc , Signal Transduction , Toll-Like Receptors , Humans , Multiple Myeloma/genetics , Multiple Myeloma/immunology , Multiple Myeloma/metabolism , B-Cell Maturation Antigen/genetics , B-Cell Maturation Antigen/metabolism , B-Cell Maturation Antigen/immunology , Cell Line, Tumor , Toll-Like Receptors/metabolism , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Bortezomib/pharmacology , Bortezomib/therapeutic use , Male
5.
Cancer Med ; 13(11): e7194, 2024 Jun.
Article En | MEDLINE | ID: mdl-38845529

BACKGROUND: Myc rearrangement (Myc-R) is a controversial factor linked to adverse outcomes in newly diagnosed multiple myeloma (NDMM). AIMS: This study aimed to evaluate the impact of Myc-R on the prognosis of NDMM patients and its role in risk stratification compared with traditional high-risk cytogenetic abnormalities (HRCAs). MATERIALS & METHODS: A total of 417 NDMM patients enrolled from May 2009 to September 2022 were included. Fluorescence in situ hybridization (FISH) was used to detect Myc-R and other Myc abnormalities (Myc-OA). Median progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier methods and log-rank tests. Multivariate Cox regression analysis was used to identify independent risk factors. RESULTS: Myc-R was identified in 13.7% of patients, while 14.6% had Myc-OA. Patients with Myc-R had significantly shorter median PFS (15.9 months) and OS (25.1 months) compared with those with Myc-OA (24.5 months PFS; 29.8 months OS) and Myc-negative (Myc-N) status (29.8 months PFS, 29.8 months OS). Myc-R was independently associated with worse PFS and OS compared to Myc-OA. Patients with Myc-R alone had inferior median PFS (15.9 months vs. 28.1 months, p = 0.032) and OS (25.1 months vs. 61.2 months, p = 0.04) compared to those with traditional single HRCA. DISCUSSION: The study suggests that traditional single HRCA may not significantly impact survival in NDMM patients. However, incorporating Myc rearrangement or traditional double/triple-hit HRCAs into the risk stratification model improves its predictive value, highlighting the importance of Myc rearrangement in risk assessment. CONCLUSION: Myc rearrangement is an independent adverse prognostic factor in NDMM. The incorporation of Myc rearrangement or multiple HRCAs into risk stratification models improves their prognostic value, providing a novel perspective on high-risk factors in NDMM.


Gene Rearrangement , Multiple Myeloma , Proto-Oncogene Proteins c-myc , Humans , Multiple Myeloma/genetics , Multiple Myeloma/mortality , Male , Female , Middle Aged , Aged , Proto-Oncogene Proteins c-myc/genetics , Prognosis , In Situ Hybridization, Fluorescence , Risk Assessment/methods , Risk Factors , Adult , Aged, 80 and over , Progression-Free Survival , Kaplan-Meier Estimate
6.
Nat Commun ; 15(1): 4969, 2024 Jun 11.
Article En | MEDLINE | ID: mdl-38862489

Metabolic remodeling is a strategy for tumor survival under stress. However, the molecular mechanisms during the metabolic remodeling of colorectal cancer (CRC) remain unclear. Melanocyte proliferating gene 1 (MYG1) is a 3'-5' RNA exonuclease and plays a key role in mitochondrial functions. Here, we uncover that MYG1 expression is upregulated in CRC progression and highly expressed MYG1 promotes glycolysis and CRC progression independent of its exonuclease activity. Mechanistically, nuclear MYG1 recruits HSP90/GSK3ß complex to promote PKM2 phosphorylation, increasing its stability. PKM2 transcriptionally activates MYC and promotes MYC-medicated glycolysis. Conversely, c-Myc also transcriptionally upregulates MYG1, driving the progression of CRC. Meanwhile, mitochondrial MYG1 on the one hand inhibits oxidative phosphorylation (OXPHOS), and on the other hand blocks the release of Cyt c from mitochondria and inhibits cell apoptosis. Clinically, patients with KRAS mutation show high expression of MYG1, indicating a high level of glycolysis and a poor prognosis. Targeting MYG1 may disturb metabolic balance of CRC and serve as a potential target for the diagnosis and treatment of CRC.


Colorectal Neoplasms , Glycolysis , Mitochondria , Oxidative Phosphorylation , Humans , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Mitochondria/metabolism , Animals , Cell Line, Tumor , Mice , Carrier Proteins/metabolism , Carrier Proteins/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics , Thyroid Hormones/metabolism , Thyroid Hormones/genetics , Thyroid Hormone-Binding Proteins , Cell Nucleus/metabolism , Gene Expression Regulation, Neoplastic , Glycogen Synthase Kinase 3 beta/metabolism , Glycogen Synthase Kinase 3 beta/genetics , HSP90 Heat-Shock Proteins/metabolism , HSP90 Heat-Shock Proteins/genetics , Mice, Nude , Apoptosis/genetics , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Male , Female
7.
Nat Commun ; 15(1): 4739, 2024 Jun 04.
Article En | MEDLINE | ID: mdl-38834613

The overexpression of the ecotropic viral integration site-1 gene (EVI1/MECOM) marks the most lethal acute myeloid leukemia (AML) subgroup carrying chromosome 3q26 abnormalities. By taking advantage of the intersectionality of high-throughput cell-based and gene expression screens selective and pan-histone deacetylase inhibitors (HDACis) emerge as potent repressors of EVI1. To understand the mechanism driving on-target anti-leukemia activity of this compound class, here we dissect the expression dynamics of the bone marrow leukemia cells of patients treated with HDACi and reconstitute the EVI1 chromatin-associated co-transcriptional complex merging on the role of proliferation-associated 2G4 (PA2G4) protein. PA2G4 overexpression rescues AML cells from the inhibitory effects of HDACis, while genetic and small molecule inhibition of PA2G4 abrogates EVI1 in 3q26 AML cells, including in patient-derived leukemia xenografts. This study positions PA2G4 at the crosstalk of the EVI1 leukemogenic signal for developing new therapeutics and urges the use of HDACis-based combination therapies in patients with 3q26 AML.


Chromosomes, Human, Pair 3 , Histone Deacetylase Inhibitors , Leukemia, Myeloid, Acute , MDS1 and EVI1 Complex Locus Protein , Proteogenomics , Animals , Female , Humans , Mice , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Proliferation/genetics , Chromosomes, Human, Pair 3/genetics , Gene Expression Regulation, Leukemic/drug effects , Histone Deacetylase Inhibitors/pharmacology , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/metabolism , Leukemia, Myeloid, Acute/pathology , MDS1 and EVI1 Complex Locus Protein/metabolism , MDS1 and EVI1 Complex Locus Protein/genetics , Proteogenomics/methods , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Xenograft Model Antitumor Assays
8.
Proc Natl Acad Sci U S A ; 121(25): e2322452121, 2024 Jun 18.
Article En | MEDLINE | ID: mdl-38861600

Intrinsically disordered proteins (IDPs) play a crucial role in various biological phenomena, dynamically changing their conformations in response to external environmental cues. To gain a deeper understanding of these proteins, it is essential to identify the determinants that fix their structures at the atomic level. Here, we developed a pipeline for rapid crystal structure analysis of IDP using a cell-free protein crystallization (CFPC) method. Through this approach, we successfully demonstrated the determination of the structure of an IDP to uncover the key determinants that stabilize its conformation. Specifically, we focused on the 11-residue fragment of c-Myc, which forms an α-helix through dimerization with a binding partner protein. This fragment was strategically recombined with an in-cell crystallizing protein and was expressed in a cell-free system. The resulting crystal structures of the c-Myc fragment were successfully determined at a resolution of 1.92 Å and we confirmed that they are identical to the structures of the complex with the native binding partner protein. This indicates that the environment of the scaffold crystal can fix the structure of c-Myc. Significantly, these crystals were obtained directly from a small reaction mixture (30 µL) incubated for only 72 h. Analysis of eight crystal structures derived from 22 mutants revealed two hydrophobic residues as the key determinants responsible for stabilizing the α-helical structure. These findings underscore the power of our CFPC screening method as a valuable tool for determining the structures of challenging target proteins and elucidating the essential molecular interactions that govern their stability.


Cell-Free System , Crystallization , Intrinsically Disordered Proteins , Proto-Oncogene Proteins c-myc , Intrinsically Disordered Proteins/chemistry , Crystallography, X-Ray/methods , Proto-Oncogene Proteins c-myc/chemistry , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Humans , Protein Conformation , Models, Molecular , Protein Binding
9.
Cancer Res ; 84(11): 1834-1855, 2024 Jun 04.
Article En | MEDLINE | ID: mdl-38831751

Cancer cells exhibit metabolic plasticity to meet oncogene-driven dependencies while coping with nutrient availability. A better understanding of how systemic metabolism impacts the accumulation of metabolites that reprogram the tumor microenvironment (TME) and drive cancer could facilitate development of precision nutrition approaches. Using the Hi-MYC prostate cancer mouse model, we demonstrated that an obesogenic high-fat diet (HFD) rich in saturated fats accelerates the development of c-MYC-driven invasive prostate cancer through metabolic rewiring. Although c-MYC modulated key metabolic pathways, interaction with an obesogenic HFD was necessary to induce glycolysis and lactate accumulation in tumors. These metabolic changes were associated with augmented infiltration of CD206+ and PD-L1+ tumor-associated macrophages (TAM) and FOXP3+ regulatory T cells, as well as with the activation of transcriptional programs linked to disease progression and therapy resistance. Lactate itself also stimulated neoangiogenesis and prostate cancer cell migration, which were significantly reduced following treatment with the lactate dehydrogenase inhibitor FX11. In patients with prostate cancer, high saturated fat intake and increased body mass index were associated with tumor glycolytic features that promote the infiltration of M2-like TAMs. Finally, upregulation of lactate dehydrogenase, indicative of a lactagenic phenotype, was associated with a shorter time to biochemical recurrence in independent clinical cohorts. This work identifies cooperation between genetic drivers and systemic metabolism to hijack the TME and promote prostate cancer progression through oncometabolite accumulation. This sets the stage for the assessment of lactate as a prognostic biomarker and supports strategies of dietary intervention and direct lactagenesis blockade in treating advanced prostate cancer. SIGNIFICANCE: Lactate accumulation driven by high-fat diet and MYC reprograms the tumor microenvironment and promotes prostate cancer progression, supporting the potential of lactate as a biomarker and therapeutic target in prostate cancer. See related commentary by Frigo, p. 1742.


Diet, High-Fat , Lactic Acid , Obesity , Prostatic Neoplasms , Proto-Oncogene Proteins c-myc , Tumor Microenvironment , Male , Animals , Prostatic Neoplasms/pathology , Prostatic Neoplasms/metabolism , Diet, High-Fat/adverse effects , Mice , Humans , Lactic Acid/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Obesity/metabolism , Obesity/pathology , Cell Line, Tumor , Mice, Inbred C57BL , Tumor-Associated Macrophages/metabolism
10.
Biol Direct ; 19(1): 47, 2024 Jun 18.
Article En | MEDLINE | ID: mdl-38886753

BACKGROUND: Long noncoding RNAs (lncRNAs) are implicated in the initiation and progression of diffuse large B-cell lymphoma (DLBCL). Small nucleolar RNA host gene 20 (SNHG20) has been recognized as a critical lncRNA in multiple human cancers. However, the role of SNHG20 and its underlying mechanism in DLBCL are still unclear. METHODS: The expression levels of SNHG20, c-MYC, ß-catenin, and ubiquitin-specific peptidase 14 (USP14) were measured by reverse transcription-quantitative polymerase chain reaction (RT‒qPCR) and immunoblotting. Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU) incorporation, and flow cytometry assays were used to assess the proliferation and apoptosis of DLBCL cells. The transcriptional regulation of SNHG20 by c-MYC was confirmed by a luciferase reporter assay and RNA immunoprecipitation. The interaction between USP14 and ß-catenin was demonstrated using coimmunoprecipitation. A subcutaneous xenograft model was constructed to determine the role of SNHG20 in vivo. RESULTS: In the present study, we found that SNHG20 expression was upregulated in DLBCL cell lines and tissues compared to their normal counterparts. SNHG20 knockdown prominently reduced the proliferation and induced the apoptosis of U2932 and OCI-LY3 cells. However, SNHG20 overexpression increased the proliferation and apoptosis resistance of DLBCL cells. Mechanistically, the expression of SNHG20 was positively regulated by c-MYC in DLBCL cells. C-MYC directly bound to the promoter of SNHG20 to activate its transcription. SNHG20 was expressed mainly in the cytosol in DLBCL cells. SNHG20 silencing did not impact USP14 expression but markedly decreased the level of ß-catenin, the substrate of USP14, in DLBCL cells. USP14 overexpression increased the ß-catenin level, and this increase was attenuated by SNHG20 knockdown. Treatment with the proteasome inhibitor MG132 abolished SNHG20 knockdown-induced ß-catenin downregulation. Moreover, SNHG20 silencing reduced the half-life but increased the ubiquitination of ß-catenin in DLBCL cells. SNHG20 knockdown weakened the interaction between both endogenous and exogenous USP14 and ß-catenin. In turn, SNHG20 overexpression increased the c-MYC level, and this increase was attenuated by ß-catenin knockdown. Importantly, ß-catenin knockdown attenuated the SNHG20-mediated increase in DLBCL cell proliferation in vitro and tumour growth in vivo. CONCLUSIONS: Taken together, our results suggested that c-MYC-activated SNHG20 accelerated the proliferation and increased the apoptosis resistance of DLBCL cells via USP14-mediated deubiquitination of ß-catenin. The c-MYC/SNHG20 positive feedback loop may be a new target for anti-DLBCL treatment.


Cell Proliferation , Lymphoma, Large B-Cell, Diffuse , Proto-Oncogene Proteins c-myc , RNA, Long Noncoding , Ubiquitin Thiolesterase , Ubiquitination , beta Catenin , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Humans , beta Catenin/metabolism , beta Catenin/genetics , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Cell Line, Tumor , Animals , Mice , Ubiquitin Thiolesterase/genetics , Ubiquitin Thiolesterase/metabolism , Gene Expression Regulation, Neoplastic , Apoptosis , Mice, Nude
11.
Pathol Res Pract ; 259: 155381, 2024 Jul.
Article En | MEDLINE | ID: mdl-38833803

Urological cancers, including prostate, bladder, and renal cancers, are significant causes of death and negatively impact the quality of life for patients. The development and progression of these cancers are linked to the dysregulation of molecular pathways. c-Myc, recognized as an oncogene, exhibits abnormal levels in various types of tumors, and current evidence supports the therapeutic targeting of c-Myc in cancer treatment. This review aims to elucidate the role of c-Myc in driving the progression of urological cancers. c-Myc functions to enhance tumorigenesis and has been documented to increase growth and metastasis in prostate, bladder, and renal cancers. Furthermore, the dysregulation of c-Myc can result in a diminished response to therapy in these cancers. Non-coding RNAs, ß-catenin, and XIAP are among the regulators of c-Myc in urological cancers. Targeting and suppressing c-Myc therapeutically for the treatment of these cancers has been explored. Additionally, the expression level of c-Myc may serve as a prognostic factor in clinical settings.


Proto-Oncogene Proteins c-myc , Urologic Neoplasms , Humans , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Urologic Neoplasms/pathology , Urologic Neoplasms/genetics , Urologic Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , Animals
12.
Arkh Patol ; 86(3): 30-37, 2024.
Article Ru | MEDLINE | ID: mdl-38881003

OBJECTIVE: The purpose of this work was to evaluate c-MYC gene amplification in the substrate of prostate acinar adenocarcinoma at various Gleason scores and various stages of the disease, taking into account the morphological characteristics of the tumor. MATERIAL AND METHODS: The number of cases in the study was 82, including the control group - 12 cases. Morphological assessment included: determination of the total Gleason score, grading group, assessment of lymphovascular/perineural invasion, and architectural characteristics of the tumor. Gene amplification was assessed by FISH using the c-MYC (8q24)/SE8 probe. RESULTS: In all cases of the study group, amplification of the c-MYC gene was detected in the tumor, with a significant difference from the control group (p<0.05). When assessing cases with 4-6 fold copies of the gene, significant differences were established between patients with stages II and III of the disease and stage IV (10.0 and 13.5 versus 30.0) (p<0.05). Cluster amplification of the c-MYC gene was detected with equal frequency in groups of patients with stages III and IV of the disease, while in stage II of the disease, the event almost did not occur (p<0.05). A significant increase in the level of c-MYC gene amplification was found in groups with advanced stages of the disease (p<0.02). Non-cluster amplification significantly distinguishes T4M0 and T4M1 stage patients from the rest with a significant increase in the score (p<0.05). In the metastatic stage of the disease, there was an increase c-MYC gene amplification compared to the non-metastatic stage (p<0.02). The copy number of the c-MYC gene was significantly higher in cases with perineural and lymphovascular invasion, as well as in cases of cribriform tumor organization (p<0.05). CONCLUSION: Amplification of the c-MYC gene in prostate tumor cells is associated with advanced stages of the disease (T4M0 and T4M1) with an increase in the copy number of the gene during the metastatic stage of the process. It was found that increased amplification of the c-MYC gene distinguishes groups of patients whose tumors exhibit perineural and lymphovascular invasion, as well as a cribriform pattern of tumor organization.


Gene Amplification , Prostatic Neoplasms , Proto-Oncogene Proteins c-myc , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Proto-Oncogene Proteins c-myc/genetics , Middle Aged , Aged , Genes, myc/genetics , Carcinoma, Acinar Cell/genetics , Carcinoma, Acinar Cell/pathology
14.
Acta Neuropathol Commun ; 12(1): 95, 2024 06 14.
Article En | MEDLINE | ID: mdl-38877600

MYC dysregulation is pivotal in the onset and progression of IDH-mutant gliomas, mostly driven by copy-number alterations, regulatory element alterations, or epigenetic changes. Our pilot analysis uncovered instances of relative MYC overexpression without alterations in the proximal MYC network (PMN), prompting a deeper investigation into potential novel oncogenic mechanisms. Analysing comprehensive genomics profiles of 236 "IDH-mutant 1p/19q non-co-deleted" lower-grade gliomas from The Cancer Genome Atlas, we identified somatic genomic alterations within the PMN. In tumours without PMN-alterations but with MYC-overexpression, genes correlated with MYC-overexpression were identified. Our analyses yielded that 86/236 of astrocytomas exhibited no PMN-alterations, a subset of 21/86 displaying relative MYC overexpression. Within this subset, we discovered 42 genes inversely correlated with relative MYC expression, all on 19q. Further analysis pinpointed a minimal common region at 19q13.43, encompassing 15 genes. The inverse correlations of these 15 genes with relative MYC overexpression were re-confirmed using independent scRNAseq data. Further, the micro-deleted astrocytoma subset displayed significantly higher genomic instability compared to WT cases, but lower instability compared to PMN-hit cases. This newly identified 19q micro-deletion represents a potential novel mechanism underlying MYC dysregulation in astrocytomas. Given the prominence of 19q loss in IDH-mutant gliomas, our findings bear significant implications for understanding gliomagenesis.


Astrocytoma , Brain Neoplasms , Chromosome Deletion , Chromosomes, Human, Pair 19 , Isocitrate Dehydrogenase , Proto-Oncogene Proteins c-myc , Humans , Isocitrate Dehydrogenase/genetics , Astrocytoma/genetics , Astrocytoma/pathology , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Chromosomes, Human, Pair 19/genetics , Mutation
15.
Cell Rep ; 43(5): 114211, 2024 May 28.
Article En | MEDLINE | ID: mdl-38722741

Multiple myeloma (MM) remains an incurable hematological malignancy demanding innovative therapeutic strategies. Targeting MYC, the notorious yet traditionally undruggable oncogene, presents an appealing avenue. Here, using a genome-scale CRISPR-Cas9 screen, we identify the WNK lysine-deficient protein kinase 1 (WNK1) as a regulator of MYC expression in MM cells. Genetic and pharmacological inhibition of WNK1 reduces MYC expression and, further, disrupts the MYC-dependent transcriptional program. Mechanistically, WNK1 inhibition attenuates the activity of the immunoglobulin heavy chain (IgH) enhancer, thus reducing MYC transcription when this locus is translocated near the MYC locus. WNK1 inhibition profoundly impacts MM cell behaviors, leading to growth inhibition, cell-cycle arrest, senescence, and apoptosis. Importantly, the WNK inhibitor WNK463 inhibits MM growth in primary patient samples as well as xenograft mouse models and exhibits synergistic effects with various anti-MM compounds. Collectively, our study uncovers WNK1 as a potential therapeutic target in MM.


Multiple Myeloma , Proto-Oncogene Proteins c-myc , WNK Lysine-Deficient Protein Kinase 1 , Multiple Myeloma/genetics , Multiple Myeloma/drug therapy , Multiple Myeloma/pathology , Multiple Myeloma/metabolism , WNK Lysine-Deficient Protein Kinase 1/metabolism , WNK Lysine-Deficient Protein Kinase 1/genetics , Humans , Animals , Mice , Cell Line, Tumor , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Gene Expression Regulation, Neoplastic/drug effects , Immunoglobulin Heavy Chains/genetics , Cell Proliferation/drug effects , Apoptosis/drug effects , Xenograft Model Antitumor Assays
17.
Nat Commun ; 15(1): 4642, 2024 May 31.
Article En | MEDLINE | ID: mdl-38821916

Post-translational modifications of proteins in malignant transformation and tumor maintenance of pancreatic ductal adenocarcinoma (PDAC) in the context of KRAS signaling remain poorly understood. Here, we use the KPC mouse model to examine the effect of palmitoylation on pancreatic cancer progression. ZDHHC20, upregulated by KRAS, is abnormally overexpressed and associated with poor prognosis in patients with pancreatic cancer. Dysregulation of ZDHHC20 promotes pancreatic cancer progression in a palmitoylation-dependent manner. ZDHHC20 inhibits the chaperone-mediated autophagic degradation of YTHDF3 through S-palmitoylation of Cys474, which can result in abnormal accumulation of the oncogenic product MYC and thereby promote the malignant phenotypes of cancer cells. Further, we design a biologically active YTHDF3-derived peptide to competitively inhibit YTHDF3 palmitoylation mediated by ZDHHC20, which in turn downregulates MYC expression and inhibits the progression of KRAS mutant pancreatic cancer. Thus, these findings highlight the therapeutic potential of targeting the ZDHHC20-YTHDF3-MYC signaling axis in pancreatic cancer.


Acyltransferases , Carcinoma, Pancreatic Ductal , Disease Progression , Gene Expression Regulation, Neoplastic , Lipoylation , Pancreatic Neoplasms , Proto-Oncogene Proteins c-myc , Proto-Oncogene Proteins p21(ras) , Animals , Humans , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Acyltransferases/metabolism , Acyltransferases/genetics , Mice , Cell Line, Tumor , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/pathology , RNA, Messenger/metabolism , RNA, Messenger/genetics , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics , Male , Signal Transduction , RNA Stability , Female
18.
Cell Signal ; 120: 111218, 2024 Aug.
Article En | MEDLINE | ID: mdl-38734194

Glioblastoma multiforme (GBM) is the most common and aggressive primary malignant human brain tumor. Although comprehensive therapies, including chemotherapy and radiotherapy following surgery, have shown promise in prolonging survival, the prognosis for GBM patients remains poor, with an overall survival rate of only 14.6 months. Chemoresistance is a major obstacle to successful treatment and contributes to relapse and poor survival rates in glioma patients. Therefore, there is an urgent need for novel strategies to overcome chemoresistance and improve treatment outcomes for human glioma patients. Recent studies have shown that the tumor microenvironment plays a key role in chemoresistance. Our study demonstrates that upregulation of HAS2 and subsequent hyaluronan secretion promotes glioma cell proliferation, invasion, and chemoresistance in vitro and in vivo through the c-myc pathway. Targeting HAS2 sensitizes glioma cells to chemotherapeutic agents. Additionally, we found that hypoxia-inducible factor HIF1α regulates HAS2 expression. Together, our findings provide insights into the dysregulation of HAS2 and its role in chemoresistance and suggest potential therapeutic strategies for GBM.


Cell Proliferation , Drug Resistance, Neoplasm , Hypoxia-Inducible Factor 1, alpha Subunit , Proto-Oncogene Proteins c-myc , Up-Regulation , Animals , Humans , Mice , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Brain Neoplasms/genetics , Cell Line, Tumor , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Glioblastoma/metabolism , Glioblastoma/pathology , Glioblastoma/genetics , Glioma/pathology , Glioma/metabolism , Glioma/genetics , Hyaluronan Synthases/metabolism , Hyaluronan Synthases/genetics , Hyaluronic Acid/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mice, Nude , Proto-Oncogene Proteins c-myc/metabolism
19.
Am J Pathol ; 194(6): 1106-1125, 2024 Jun.
Article En | MEDLINE | ID: mdl-38749608

Zinc finger protein 471 (ZNF471) is a member of the Krüppel-related domain zinc finger protein family, and has recently attracted attention because of its anti-cancer effects. N-glycosylation regulates expression and functions of the protein. This study aimed to investigate the effects of ZNF471 N-glycosylation on the proliferation, invasion, and docetaxel sensitivity of tongue squamous cell carcinoma (TSCC). It analyzed the expression, function, and prognostic significance of ZNF471 in TSCC using bioinformatics techniques such as gene differential expression analysis, univariate Cox regression analysis, functional enrichment analysis, and gene set enrichment analysis. Using site-specific mutagenesis, this study generated three mutant sites for ZNF471 N-glycosylation to determine the effect of N-glycosylation on ZNF471 protein levels and function. Quantitative real-time PCR, Western blot analysis, and immunohistochemistry tests confirmed the down-regulation of ZNF471 expression in TSCC. Low expression of ZNF471 is associated with poor prognosis of patients with TSCC. Overexpression of ZNF471 in vitro retarded the proliferation of TSCC cells and suppressed cell invasion and migration ability. Asparagine 358 was identified as a N-glycosylation site of ZNF471. Suppressing N-glycosylation of ZNF471 enhanced the protein stability and promoted the translocation of protein to the cell nucleus. ZNF471 binding to c-Myc gene promoter suppressed oncogene c-Myc expression, thereby playing the anti-cancer effect and enhancing TSCC sensitivity to docetaxel. In all, N-glycosylation of ZNF471 affects the proliferation, invasion, and docetaxel sensitivity of TSCC via regulation of c-Myc.


Cell Proliferation , Docetaxel , Neoplasm Invasiveness , Proto-Oncogene Proteins c-myc , Tongue Neoplasms , Docetaxel/pharmacology , Humans , Tongue Neoplasms/pathology , Tongue Neoplasms/metabolism , Tongue Neoplasms/drug therapy , Tongue Neoplasms/genetics , Cell Proliferation/drug effects , Glycosylation/drug effects , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Gene Expression Regulation, Neoplastic/drug effects , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Drug Resistance, Neoplasm , Prognosis , Female , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/genetics , Cell Movement/drug effects , Male
20.
Nat Commun ; 15(1): 3873, 2024 May 08.
Article En | MEDLINE | ID: mdl-38719882

Human glial progenitor cells (hGPCs) exhibit diminished expansion competence with age, as well as after recurrent demyelination. Using RNA-sequencing to compare the gene expression of fetal and adult hGPCs, we identify age-related changes in transcription consistent with the repression of genes enabling mitotic expansion, concurrent with the onset of aging-associated transcriptional programs. Adult hGPCs develop a repressive transcription factor network centered on MYC, and regulated by ZNF274, MAX, IKZF3, and E2F6. Individual over-expression of these factors in iPSC-derived hGPCs lead to a loss of proliferative gene expression and an induction of mitotic senescence, replicating the transcriptional changes incurred during glial aging. miRNA profiling identifies the appearance of an adult-selective miRNA signature, imposing further constraints on the expansion competence of aged GPCs. hGPC aging is thus associated with acquisition of a MYC-repressive environment, suggesting that suppression of these repressors of glial expansion may permit the rejuvenation of aged hGPCs.


Aging , MicroRNAs , Neuroglia , Transcription Factors , Humans , Neuroglia/metabolism , Neuroglia/cytology , Aging/genetics , Aging/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Cellular Senescence/genetics , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/cytology , Stem Cells/metabolism , Stem Cells/cytology , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Adult , Gene Regulatory Networks , Cell Proliferation/genetics , Gene Expression Regulation, Developmental , Gene Expression Profiling
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