RESUMO
BACKGROUND: Cholangiocarcinoma (CCA) is a highly malignant, rapidly progressing tumor of the bile duct. Owing to its chemoresistance, it always has an extremely poor prognosis. Therefore, detailed elucidation of the mechanisms of chemoresistance and identification of therapeutic targets are still needed. METHODS: We analyzed the expression of MBD2 (Methyl-CpG-binding domain 2) in CCA and normal bile duct tissues using the public database and immunohistochemistry (IHC). The roles of MBD2 in CCA cell proliferation, migration, and chemoresistance ability were validated through CCK-8, plate cloning assay, wound healing assays and xenograft mouse model. In addition, we constructed a primary CCA mouse model to further confirm the effect of MBD2. RNA-seq and co-IP-MS were used to identify the mechanisms by how MBD2 leads to chemoresistance. RESULTS: MBD2 was upregulated in CCA. It promoted the proliferation, migration and chemoresistance of CCA cells. Mechanistically, MBD2 directly interacted with WDR5, bound to the promoter of ABCB1, promoted the trimethylation of H3K4 in this region through KMT2A, and activated the expression of ABCB1. Knocking down WDR5 or KMT2A blocked the transcriptional activation of ABCB1 by MBD2. The molecular inhibitor MM-102 targeted the interaction of WDR5 with KMT2A. MM-102 inhibited the expression of ABCB1 in CCA cells and decreased the chemoresistance of CCA to cisplatin. CONCLUSION: MBD2 promotes the progression and chemoresistance of CCA through interactions with WDR5. MM-102 can effectively block this process and increase the sensitivity of CCA to cisplatin.
Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Proteínas de Ligação a DNA , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Peptídeos e Proteínas de Sinalização Intracelular , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Humanos , Animais , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Proliferação de Células , Linhagem Celular Tumoral , Masculino , Feminino , Regulação Neoplásica da Expressão Gênica , Ensaios Antitumorais Modelo de Xenoenxerto , Movimento Celular , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genéticaRESUMO
G9a is a histone methyltransferase that catalyzes the methylation of histone 3 lysine 9 (H3K9), which is involved in the regulation of gene expression. We had previously reported that G9a is expressed in developing tendons in vivo and in vitro and that G9a-deficient tenocytes show impaired proliferation and differentiation in vitro. In this study, we investigated the functions of G9a in tendon development in vivo by using G9a conditional knockout (G9a cKO) mice. We crossed Sox9Cre/+ mice with G9afl/fl mice to generate G9afl/fl; Sox9Cre/+ mice. The G9a cKO mice showed hypoplastic tendon formation at 3 weeks of age. Bromodeoxyuridine labeling on embryonic day 16.5 (E16.5) revealed decreased cell proliferation in the tenocytes of G9a cKO mice. Immunohistochemical analysis revealed decreased expression levels of G9a and its substrate, H3K9me2, in the vertebral tendons of G9a cKO mice. The tendon tissue of the vertebrae and limbs of G9a cKO mice showed reduced expression of a tendon marker, tenomodulin (Tnmd), and col1a1 genes, suggesting that tenocyte differentiation was suppressed. Overexpression of G9a resulted in enhancement of Tnmd and col1a1 expression in tenocytes in vitro. These results suggest that G9a regulates the proliferation and differentiation of tendon progenitor cells during tendon development. Thus, our results suggest that G9a plays an essential role in tendon development.
Assuntos
Diferenciação Celular , Proliferação de Células , Histona-Lisina N-Metiltransferase , Camundongos Knockout , Tendões , Animais , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Tendões/metabolismo , Tendões/embriologia , Camundongos , Tenócitos/metabolismo , Histonas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Cadeia alfa 1 do Colágeno Tipo I/metabolismo , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOX9/genéticaRESUMO
Pluripotent stem cells can differentiate into distinct cell types but the intracellular pathways controlling cell fate choice are not well understood. The social amoeba Dictyostelium discoideum is a simplified system to study choice preference as proliferating amoebae enter a developmental cycle upon starvation and differentiate into two major cell types, stalk and spores, organised in a multicellular fruiting body. Factors such as acidic vesicle pH predispose amoebae to one fate. Here we show that the mechanistic target of rapamycin complex 1 (mTORC1) pathway has a role in cell fate bias in Dictyostelium. Inhibiting the mTORC1 pathway activity by disruption of Rheb (activator Ras homolog enriched in brain), or treatment with the mTORC1 inhibitor rapamycin prior to development, biases cells to a spore cell fate. Conversely activation of the pathway favours stalk cell differentiation. The Set1 histone methyltransferase, responsible for histone H3 lysine4 methylation, in Dictyostelium cells regulates transcription at the onset of development. Disruption of Set1 leads to high mTORC1 pathway activity and stalk cell predisposition. The ability of the mTORC1 pathway to regulate cell fate bias of cells undergoing differentiation offers a potential target to increase the efficiency of stem cell differentiation into a particular cell type.
Assuntos
Diferenciação Celular , Dictyostelium , Alvo Mecanístico do Complexo 1 de Rapamicina , Transdução de Sinais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Dictyostelium/metabolismo , Dictyostelium/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Sirolimo/farmacologia , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genéticaRESUMO
BACKGROUND: Dexamethasone (Dex), a synthetic glucocorticoid that acts by binding to the glucocorticoid receptor (GR), has been widely applied to treat leukemia and lymphoma; however, the precise mechanism underlying Dex action is still not well elucidated. DOT1L, a histone H3-lysine79 (H3K79) methyltransferase, has been linked to multiple cancer types, particularly mixed lineage leukemia (MLL) gene rearranged leukemia, but its contribution to lymphoma is yet to be delineated. Analysis from the TCGA database displayed that DOT1L was highly expressed in lymphoma and leukemia. RESULTS: We initially demonstrated that DOT1L served as a new target gene controlled by GR, and the downregulation of DOT1L was critical for the killing of B-lymphoma cells by Dex. Further study revealed that Dex had no impact on the transcriptional activity of the DOT1L promoter, rather it reduced the mRNA level of DOT1L at the posttranscriptional level. In addition, knockdown of DOT1L remarkably inhibited the B-lymphoma cell growth. CONCLUSIONS: Overall, our findings indicated that DOT1L may serve as a potential drug target and a promising biomarker of Dex sensitivity when it comes to treating B lymphoma.
Assuntos
Proliferação de Células , Dexametasona , Histona-Lisina N-Metiltransferase , Linfoma de Células B , Metiltransferases , Receptores de Glucocorticoides , Humanos , Dexametasona/farmacologia , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Linfoma de Células B/genética , Metiltransferases/metabolismo , Metiltransferases/genética , Metiltransferases/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos dos fármacosRESUMO
The effects of HIF1A knockdown by RNA interference on the histone H3K9 methylation in human umbilical cord mesenchymal stromal cells in vitro under conditions of 24-h exposure to hypoxia (1% O2) were studied. Evaluation of transcriptional activity of genes involved in the regulation of H3K9 methylation (KDM3A, KDM4A, and EHMT2) and the cytofluorimetric analysis of the expression of the corresponding antigens and H3K9 methylation level demonstrated a pronounced stimulating effect of hypoxic exposure. Moreover, the expression of KDM4A and EHMT2 was regulated by HIF1A-mediated mechanism, unlike KDM3A; the level of the corresponding proteins depended on HIF1A. In addition, the HIF-1-dependent regulation of KDM3A, KDM4A, and EHMT2/G9a, and directly the H3K9 methylation level in mesenchymal stromal cells also took place under normoxia conditions.
Assuntos
Hipóxia Celular , Histonas , Subunidade alfa do Fator 1 Induzível por Hipóxia , Histona Desmetilases com o Domínio Jumonji , Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Humanos , Histonas/metabolismo , Histonas/genética , Metilação , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia Celular/genética , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Interferência de RNA , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo , Células Cultivadas , Técnicas de Silenciamento de Genes , Regulação da Expressão GênicaRESUMO
Germline variants in the NSD1 gene are responsible for Sotos syndrome, while somatic variants promote neoplastic cell transformation. Our previous studies revealed three alternative RNA isoforms of NSD1 present in fibroblast cell lines (FBs): the canonical full transcript and 2 alternative transcripts, termed AT2 (NSD1 Δ5Δ7) and AT3 (NSD1 Δ19-23 at the 5' end). The precise molecular pathways affected by each specific isoform of NSD1 are uncharacterized to date. To elucidate the role of these isoforms, their expression was suppressed by siRNA knockdown in FBs and protein expression and transcriptome data was explored. We demonstrate that one gene target of NSD1 isoform AT2 is ARP3 actin-related protein 3 homolog B (ACTR3B). We show that loss of both canonical NSD1 and AT2 isoforms impaired the ability of fibroblasts to regulate the actin cytoskeleton, and we observed that this caused selective loss of stress fibers. Our findings provide novel insights into NSD1 function by distinguishing isoform function and demonstrating an essential role of NSD1 in regulating the actin cytoskeleton and stress fiber formation in fibroblasts.
Assuntos
Citoesqueleto de Actina , Fibroblastos , Histona-Lisina N-Metiltransferase , Isoformas de Proteínas , Fibroblastos/metabolismo , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Divisão Celular/genética , Linhagem Celular , Processamento Alternativo , Fibras de Estresse/metabolismoRESUMO
SETD8 is a methyltransferase that is overexpressed in several cancers, which monomethylates H4K20 as well as other non-histone targets such as PCNA or p53. We here report novel SETD8 inhibitors, which were discovered while trying to identify chemicals that prevent 53BP1 foci formation, an event mediated by H4K20 methylation. Consistent with previous reports, SETD8 inhibitors induce p53 expression, although they are equally toxic for p53 proficient or deficient cells. Thermal stability proteomics revealed that the compounds had a particular impact on nucleoli, which was confirmed by fluorescent and electron microscopy. Similarly, Setd8 deletion generated nucleolar stress and impaired ribosome biogenesis, supporting that this was an on-target effect of SETD8 inhibitors. Furthermore, a genome-wide CRISPR screen identified an enrichment of nucleolar factors among those modulating the toxicity of SETD8 inhibitors. Accordingly, the toxicity of SETD8 inhibition correlated with MYC or mTOR activity, key regulators of ribosome biogenesis. Together, our study provides a new class of SETD8 inhibitors and a novel biomarker to identify tumors most likely to respond to this therapy.
Assuntos
Histona-Lisina N-Metiltransferase , Ribossomos , Humanos , Ribossomos/metabolismo , Ribossomos/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Nucléolo Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Serina-Treonina Quinases TOR/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genéticaRESUMO
Functional genomic screens in two-dimensional cell culture models are limited in identifying therapeutic targets that influence the tumor microenvironment. By comparing targeted CRISPR-Cas9 screens in a two-dimensional culture with xenografts derived from the same cell line, we identified MEN1 as the top hit that confers differential dropout effects in vitro and in vivo. MEN1 knockout in multiple solid cancer types does not impact cell proliferation in vitro but significantly promotes or inhibits tumor growth in immunodeficient or immunocompetent mice, respectively. Mechanistically, MEN1 knockout redistributes MLL1 chromatin occupancy, increasing H3K4me3 at repetitive genomic regions, activating double-stranded RNA expression and increasing neutrophil and CD8+ T cell infiltration in immunodeficient and immunocompetent mice, respectively. Pharmacological inhibition of the menin-MLL interaction reduces tumor growth in a CD8+ T cell-dependent manner. These findings reveal tumor microenvironment-dependent oncogenic and tumor-suppressive functions of MEN1 and provide a rationale for targeting MEN1 in solid cancers.
Assuntos
Linfócitos T CD8-Positivos , Sistemas CRISPR-Cas , Histona-Lisina N-Metiltransferase , Proteínas Proto-Oncogênicas , Microambiente Tumoral , Animais , Feminino , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Proteína de Leucina Linfoide-Mieloide/genética , Neoplasias/genética , Neoplasias/patologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismoRESUMO
The histone lysine methyltransferase SUV420H1 preferentially targets the H2A.Z-containing nucleosome core particle (H2A.Z-NCP) and catalyzes the H4K20me2 modification at replication origins. Here, we present a protocol for preparing SUV420H1 in complex with the nucleosome containing H2A.Z and H4K20Ecx for structure determination. We describe steps for the installation of S-ethyl-cysteine (Ecx), nucleosome and complex preparation, and performing the cryoelectron microscopy (cryo-EM) sample check. This protocol substitutes lysine 20 in histone H4 with S-ethyl-cysteine (H4K20Ecx), which enhances the stability of the interaction between SUV420H1 and nucleosomes. For complete details on the use and execution of this protocol, please refer to Huang et al.1.
Assuntos
Microscopia Crioeletrônica , Histona-Lisina N-Metiltransferase , Histonas , Nucleossomos , Nucleossomos/metabolismo , Nucleossomos/química , Histonas/metabolismo , Histonas/química , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/química , Microscopia Crioeletrônica/métodos , HumanosRESUMO
The histone lysine methyltransferase NSD2 has been recognized as an attractive target for cancer treatment, due to the functional implication of its dysregulation in the initiation and progression of many cancers. Although considerable efforts have been made to develop NSD2 small-molecule inhibitors, highly potent and selective ones are still rarely available till now. Here, we report the discovery of a series of novel NSD2 inhibitors via an extensive SAR exploration of the privileged quinazoline scaffold within compound 8. The most promising compound 42 showed excellent NSD2 enzymatic inhibitory activity and good antiproliferative activity in cells. In addition, it demonstrated favorable pharmacokinetic properties and significantly inhibited the tumor growth in a RS411 tumor xenograft model with good safety. Taken together, compound 42 could be a promising NSD2 inhibitor and deserves further investigation.
Assuntos
Histona-Lisina N-Metiltransferase , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Animais , Relação Estrutura-Atividade , Quinazolinas/farmacologia , Quinazolinas/química , Quinazolinas/síntese química , Quinazolinas/farmacocinética , Camundongos , Descoberta de Drogas , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus , RatosAssuntos
Resistencia a Medicamentos Antineoplásicos , Histona-Lisina N-Metiltransferase , Proteína de Leucina Linfoide-Mieloide , Proteínas Proto-Oncogênicas , Humanos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histona-Lisina N-Metiltransferase/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas de Fusão Oncogênica/antagonistas & inibidores , AnimaisRESUMO
The translocation t(14;18) activates BCL2 and is considered the initiating genetic lesion in most follicular lymphomas (FL). Surprisingly, FL patients fail to respond to the BCL2 inhibitor, Venetoclax. We show that mutations and deletions affecting the histone lysine methyltransferase SETD1B (KMT2G) occur in 7% of FLs and 16% of diffuse large B cell lymphomas (DLBCL). Deficiency in SETD1B confers striking resistance to Venetoclax and an experimental MCL-1 inhibitor. SETD1B also acts as a tumor suppressor and cooperates with the loss of KMT2D in lymphoma development in vivo. Consistently, loss of SETD1B in human lymphomas typically coincides with loss of KMT2D. Mechanistically, SETD1B is required for the expression of several proapoptotic BCL2 family proteins. Conversely, inhibitors of the KDM5 histone H3K4 demethylases restore BIM and BIK expression and synergize with Venetoclax in SETD1B-deficient lymphomas. These results establish SETD1B as an epigenetic regulator of cell death and reveal a pharmacological strategy to augment Venetoclax sensitivity in lymphoma.
Assuntos
Apoptose , Histona-Lisina N-Metiltransferase , Mutação , Proteínas Proto-Oncogênicas c-bcl-2 , Animais , Humanos , Camundongos , Apoptose/genética , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/patologia , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/farmacologiaRESUMO
Pediatric acute myeloid leukemia (AML) is an aggressive blood cancer with a poor prognosis and high relapse rate. Current challenges in the identification of immunotherapy targets arise from patient-specific blast immunophenotypes and their change during disease progression. To overcome this, we present a new computational research tool to rapidly identify malignant cells. We generated single-cell flow cytometry profiles of 21 pediatric AML patients with matched samples at diagnosis, remission, and relapse. We coupled a classifier to an autoencoder for anomaly detection and classified malignant blasts with 90% accuracy. Moreover, our method assigns a developmental stage to blasts at the single-cell level, improving current classification approaches based on differentiation of the dominant phenotype. We observed major immunophenotype and developmental stage alterations between diagnosis and relapse. Patients with KMT2A rearrangement had more profound changes in their blast immunophenotypes at relapse compared to patients with other molecular features. Our method provides new insights into the immunophenotypic composition of AML blasts in an unbiased fashion and can help to define immunotherapy targets that might improve personalized AML treatment.
Assuntos
Imunofenotipagem , Leucemia Mieloide Aguda , Análise de Célula Única , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/genética , Criança , Análise de Célula Única/métodos , Feminino , Masculino , Pré-Escolar , Adolescente , Proteína de Leucina Linfoide-Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/metabolismo , Citometria de Fluxo/métodos , Lactente , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Biologia Computacional/métodos , PrognósticoRESUMO
Leishmania donovani, a protozoan parasite, causes visceral leishmaniasis. The parasite modifies the global gene expressions of the host genome, facilitating its survival within the host. Thus, the host epigenetic modulators play important roles in host-pathogen interaction and host epigenetic modification in response to infection. Previously, we had reported that the host epigenetic modulator, histone deacetylase 1 (HDAC1) expression was upregulated on Leishmania donovani infection. This upregulation led to the repression of host defensin genes in response to the infection. In this paper, we have investigated the interplay between the host DOT1L, a histone methyltransferase, and HDAC1 in response to Leishmania donovani infection. We show that the expression of DOT1L is upregulated both at transcript and protein level following infection leading to increase in H3K79me, H3K79me2, and H3K79me3 levels. ChIP experiments showed that DOT1L regulated the expression of HDAC1. Downregulation of DOT1L using siRNA resulted in decreased expression of HDAC1 and increased transcription of defensin genes and thereby, lower parasite load. In turn, HDAC1 regulates the expression of DOT1L on Leishmania donovani infection as downregulation of HDAC1 using siRNA led to reduced expression of DOT1L. Thus, during Leishmania donovani infection, an interplay between DOT1L and HDAC1 regulates the expression of these two histone modifiers leading to downregulation of defensin gene expression.
Assuntos
Histona Desacetilase 1 , Histona-Lisina N-Metiltransferase , Leishmania donovani , Humanos , Leishmania donovani/genética , Histona Desacetilase 1/metabolismo , Histona Desacetilase 1/genética , Células THP-1 , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Leishmaniose Visceral/parasitologia , Histonas/metabolismo , Histonas/genética , Interações Hospedeiro-Patógeno , Regulação da Expressão Gênica , Epigênese GenéticaRESUMO
While lysine methylation is well-known for regulating gene expression transcriptionally, its implications in translation have been largely uncharted. Trimethylation at lysine 22 (K22me3) on RPL40, a core ribosomal protein located in the GTPase activation center, was first reported 27 years ago. Yet, its methyltransferase and role in translation remain unexplored. Here, we report that SMYD5 has robust in vitro activity toward RPL40 K22 and primarily catalyzes RPL40 K22me3 in cells. The loss of SMYD5 and RPL40 K22me3 leads to reduced translation output and disturbed elongation as evidenced by increased ribosome collisions. SMYD5 and RPL40 K22me3 are upregulated in hepatocellular carcinoma (HCC) and negatively correlated with patient prognosis. Depleting SMYD5 renders HCC cells hypersensitive to mTOR inhibition in both 2D and 3D cultures. Additionally, the loss of SMYD5 markedly inhibits HCC development and growth in both genetically engineered mouse and patient-derived xenograft (PDX) models, with the inhibitory effect in the PDX model further enhanced by concurrent mTOR suppression. Our findings reveal a novel role of the SMYD5 and RPL40 K22me3 axis in translation elongation and highlight the therapeutic potential of targeting SMYD5 in HCC, particularly with concurrent mTOR inhibition. This work also conceptually broadens the understanding of lysine methylation, extending its significance from transcriptional regulation to translational control.
Assuntos
Carcinoma Hepatocelular , Histona-Lisina N-Metiltransferase , Neoplasias Hepáticas , Lisina , Metiltransferases , Proteínas Ribossômicas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Lisina/metabolismo , Metilação , Camundongos Nus , Biossíntese de Proteínas , Proteínas Ribossômicas/metabolismo , Proteínas Ribossômicas/genética , Metiltransferases/genética , Metiltransferases/metabolismoRESUMO
BACKGROUND: SET domain-containing histone lysine methyltransferases (HKMTs) and JmjC domain-containing histone demethylases (JHDMs) are essential for maintaining dynamic changes in histone methylation across parasite development and infection. However, information on the HKMTs and JHDMs in human pathogenic piroplasms, such as Babesia duncani and Babesia microti, and in veterinary important pathogens, including Babesia bigemina, Babesia bovis, Theileria annulata and Theileria parva, is limited. RESULTS: A total of 38 putative KMTs and eight JHDMs were identified using a comparative genomics approach. Phylogenetic analysis revealed that the putative KMTs can be divided into eight subgroups, while the JHDMs belong to the JARID subfamily, except for BdJmjC1 (BdWA1_000016) and TpJmjC1 (Tp Muguga_02g00471) which cluster with JmjC domain only subfamily members. The motifs of SET and JmjC domains are highly conserved among piroplasm species. Interspecies collinearity analysis provided insight into the evolutionary duplication events of some SET domain and JmjC domain gene families. Moreover, relative gene expression analysis by RTâqPCR demonstrated that the putative KMT and JHDM gene families were differentially expressed in different intraerythrocytic developmental stages of B. duncani, suggesting their role in Apicomplexa parasite development. CONCLUSIONS: Our study provides a theoretical foundation and guidance for understanding the basic characteristics of several important piroplasm KMT and JHDM families and their biological roles in parasite differentiation.
Assuntos
Babesia , Filogenia , Babesia/genética , Babesia/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/química , Genômica , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Histona Desmetilases com o Domínio Jumonji/química , Animais , Humanos , Genoma de Protozoário , Domínios PR-SET/genéticaRESUMO
Breast cancer is a major public health concern worldwide, being the most commonly diagnosed cancer among women and a leading cause of cancer-related deaths. Recent studies have highlighted the significance of non-histone methylation in breast cancer, which modulates the activity, interaction, localization, and stability of target proteins. This regulation affects critical processes such as oncogenesis, tumor growth, proliferation, invasion, migration, and immune responses. This review delves into the enzymes responsible for non-histone methylation, such as protein arginine methyltransferases (PRMTs), lysine methyltransferases (KMTs), and demethylases, and explores their roles in breast cancer. By elucidating the molecular mechanisms and functional consequences of non-histone methylation, this review aims to provide insights into novel therapeutic strategies targeting these pathways. The therapeutic potential of targeting non-histone methylation to overcome drug resistance and enhance treatment efficacy in breast cancer is also discussed, highlighting promising avenues for future research and clinical applications.
Assuntos
Neoplasias da Mama , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Animais , Metilação , Terapia de Alvo Molecular , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Proteína-Arginina N-Metiltransferases/genética , Histona-Lisina N-Metiltransferase/metabolismoRESUMO
Hydroquinone (HQ), a metabolite of benzene, is frequently utilized as a surrogate for benzene in in vitro studies and is associated with the development of acute myeloid leukemia (AML). In the hemotoxicity caused by benzene and HQ, cell apoptosis plays a key role. However, the molecular mechanisms underlying HQ are unknown. Studies have indicated that Suv39h1 is involved in regulating cell division and proliferation by regulating histone H3K9me3. Meanwhile, the Wnt/ß-catenin signaling pathway also plays a significant role in cell proliferation and apoptosis. Therefore, this study was aimed at exploring the regulatory role of Suv39h1 and the Wnt/ß-catenin signaling pathway in the effects of HQ on bone marrow mesenchymal stem cells (BMSCs), as well as its influence on cell proliferation and apoptosis. The results demonstrated that HQ elevated the levels of Suv39h1 and H3K9me3 and activated the Wnt/ß-catenin signaling pathway by upregulating ß-catenin, Wnt2b, C-myc, and Cyclin D1 and downregulating Wnt5a, resulting in an increase in cell growth and a decrease in apoptosis. Suv39h1 knockdown inhibited the Wnt/ß-catenin signaling pathway. Meanwhile, inhibition of the Wnt/ß-catenin signaling pathway resulted in the down-regulation of Suv39h1 and H3K9me3 in BMSCs. They both promoted cell proliferation and inhibited apoptosis in the effects of HQ on BMSCs by downregulating the expression of Cyt-C, Bax, Caspase 3, and Caspase 9 and upregulating the expression of Bcl-xl. Therefore, we concluded that Suv39h1 and the Wnt/ß-catenin signaling pathway may mutually regulate each other in the effects of HQ on BMSCs in order to ameliorate the altered function of BMSCs.
Assuntos
Apoptose , Proliferação de Células , Hidroquinonas , Células-Tronco Mesenquimais , Via de Sinalização Wnt , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Apoptose/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Animais , Hidroquinonas/toxicidade , Células Cultivadas , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , beta Catenina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , MasculinoRESUMO
Monocytic acute myeloid leukemia (AML) responds poorly to current treatments, including venetoclax-based therapy. We conducted in vivo and in vitro CRISPR-Cas9 library screenings using a mouse monocytic AML model and identified SETDB1 and its binding partners (ATF7IP and TRIM33) as crucial tumor promoters in vivo. The growth-inhibitory effect of Setdb1 depletion in vivo is dependent mainly on natural killer (NK) cell-mediated cytotoxicity. Mechanistically, SETDB1 depletion upregulates interferon-stimulated genes and NKG2D ligands through the demethylation of histone H3 Lys9 at the enhancer regions, thereby enhancing their immunogenicity to NK cells and intrinsic apoptosis. Importantly, these effects are not observed in non-monocytic leukemia cells. We also identified the expression of myeloid cell nuclear differentiation antigen (MNDA) and its murine counterpart Ifi203 as biomarkers to predict the sensitivity of AML to SETDB1 depletion. Our study highlights the critical and selective role of SETDB1 in AML with granulo-monocytic differentiation and underscores its potential as a therapeutic target for current unmet needs.