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1.
Rinsho Ketsueki ; 62(8): 988-997, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34497239

RESUMO

Leukemia is caused by uncontrolled proliferation of immature hematopoietic progenitors. MLL fusion proteins, generated by chromosomal translocations, activate a broad range of previously transcribed genes to achieve the same expression profile as that of the parent cell in the daughter cells, thereby promoting self-renewal. Normally, replication of the expression profile only occurs in the hematopoietic stem cells (HSCs). A transactivation system comprised of MLL and AF4/ENL/P-TEFb (AEP) complexes promotes it by reactivating CpG-rich promoters. In the normal hematopoietic development, this system is tightly regulated and progressively suppressed during the course of hematopoietic differentiation so that non-HSC hematopoietic cells would not self-renew. Genetic mutations such as fusions of MLL and AEP components generate a constitutively active form of the MLL transcriptional machinery, which aberrantly promotes self-renewal even in non-HSC hematopoietic cells. In this review, I depict a molecular mechanism of MLL fusion-mediated leukemogenesis from a standpoint that leukemogenesis is driven by aberrant self-renewal that is mediated by hyper-active transcriptional machinery, and introduce several molecularly targeted therapies in the making which specifically perturb this transactivation system.


Assuntos
Leucemia , Proteína de Leucina Linfoide-Mieloide , Carcinogênese , Células-Tronco Hematopoéticas , Humanos , Leucemia/genética , Leucemia/terapia , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética
2.
Am J Hum Genet ; 108(9): 1611-1630, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34343493

RESUMO

Genome-wide association studies (GWASs) have identified a melanoma-associated locus on chromosome band 7p21.1 with rs117132860 as the lead SNP and a secondary independent signal marked by rs73069846. rs117132860 is also associated with tanning ability and cutaneous squamous cell carcinoma (cSCC). Because ultraviolet radiation (UVR) is a key environmental exposure for all three traits, we investigated the mechanisms by which this locus contributes to melanoma risk, focusing on cellular response to UVR. Fine-mapping of melanoma GWASs identified four independent sets of candidate causal variants. A GWAS region-focused Capture-C study of primary melanocytes identified physical interactions between two causal sets and the promoter of the aryl hydrocarbon receptor (AHR). Subsequent chromatin state annotation, eQTL, and luciferase assays identified rs117132860 as a functional variant and reinforced AHR as a likely causal gene. Because AHR plays critical roles in cellular response to dioxin and UVR, we explored links between this SNP and AHR expression after both 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and ultraviolet B (UVB) exposure. Allele-specific AHR binding to rs117132860-G was enhanced following both, consistent with predicted weakened AHR binding to the risk/poor-tanning rs117132860-A allele, and allele-preferential AHR expression driven from the protective rs117132860-G allele was observed following UVB exposure. Small deletions surrounding rs117132860 introduced via CRISPR abrogates AHR binding, reduces melanocyte cell growth, and prolongs growth arrest following UVB exposure. These data suggest AHR is a melanoma susceptibility gene at the 7p21.1 risk locus and rs117132860 is a functional variant within a UVB-responsive element, leading to allelic AHR expression and altering melanocyte growth phenotypes upon exposure.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma de Células Escamosas/genética , Cromossomos Humanos Par 7 , Loci Gênicos , Melanócitos/metabolismo , Melanoma/genética , Receptores de Hidrocarboneto Arílico/genética , Neoplasias Cutâneas/genética , Alelos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Cromatina/química , Cromatina/metabolismo , Regulação da Expressão Gênica , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/patologia , Melanócitos/efeitos da radiação , Melanoma/metabolismo , Melanoma/patologia , Dibenzodioxinas Policloradas/toxicidade , Polimorfismo de Nucleotídeo Único , Cultura Primária de Células , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Banho de Sol , Raios Ultravioleta/efeitos adversos
3.
Int J Mol Sci ; 22(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34445087

RESUMO

The miR-31 host gene (MIR31HG) encodes a long non-coding RNA (LncRNA) that harbors miR-31 in its intron 2; miR-31 promotes malignant neoplastic progression. Overexpression of MIR31HG and of miR-31 occurs during oral squamous cell carcinoma (OSCC). However, the downstream effectors modulated by MIR31HG during OSCC pathogenesis remain unclear. The present study identifies up-regulation of MIR31HG expression during the potentially premalignant disorder stage of oral carcinogenesis. The potential of MIR31HG to enhance oncogenicity and to activate Wnt and FAK was identified when there was exogenous MIR31HG expression in OSCC cells. Furthermore, OSCC cell subclones with MIR31HG deleted were established using a Crispr/Cas9 strategy. RNA sequencing data obtained from cells expressing MIR31HG, cells with MIR31HG deleted and cells with miR-31 deleted identified 17 candidate genes that seem to be modulated by MIR31HG in OSCC cells. A TCGA database algorithm pinpointed MMP1, BMP2 and Limb-Bud and Heart development (LBH) as effector genes controlled by MIR31HG during OSCC. Exogenous LBH expression decreases tumor cell invasiveness, while knockdown of LBH reverses the oncogenic suppression present in MIR31HG deletion subclones. The study provides novel insights demonstrating the contribution of the MIR31HG-LBH cascade to oral carcinogenesis.


Assuntos
Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Bucais/genética , RNA Longo não Codificante/genética , Fatores de Transcrição/genética , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma de Células Escamosas/patologia , Progressão da Doença , Humanos , Neoplasias Bucais/patologia , Regulação para Cima
4.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445164

RESUMO

Powerful bioinformatics tools have provided a wealth of novel miRNA-transcription factor networks crucial in controlling gene regulation. In this review, we focus on the biological functions of miRNAs targeting ZNF521, explaining the molecular mechanisms by which the dysregulation of this axis contributes to malignancy. ZNF521 is a stem cell-associated co-transcription factor implicated in the regulation of hematopoietic, neural, and mesenchymal stem cells. The aberrant expression of ZNF521 transcripts, frequently associated with miRNA deregulation, has been detected in several tumors including pancreatic, hepatocellular, gastric, bladder transitional cell carcinomas as well as in breast and ovarian cancers. miRNA expression profiling tools are currently identifying a multitude of miRNAs, involved together with oncogenes and TFs in the regulation of oncogenesis, including ZNF521, which may be candidates for diagnostic and prognostic biomarkers of cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias/genética , Animais , Carcinogênese/genética , Redes Reguladoras de Genes , Humanos , Fatores de Transcrição/genética
5.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445617

RESUMO

HOX transcription factors are members of an evolutionarily conserved family of proteins required for the establishment of the anteroposterior body axis during bilaterian development. Although they are often deregulated in cancers, the molecular mechanisms by which they act as oncogenes or tumor suppressor genes are only partially understood. Since the MAPK/ERK signaling pathway is deregulated in most cancers, we aimed at apprehending if and how the Hox proteins interact with ERK oncogenicity. Using an in vivo neoplasia model in the chicken embryo consisting in the overactivation of the ERK1/2 kinases in the trunk neural tube, we analyzed the consequences of the HOXB8 gain of function at the morphological and transcriptional levels. We found that HOXB8 acts as a tumor suppressor, counteracting ERK-induced neoplasia. The HOXB8 tumor suppressor function relies on a large reversion of the oncogenic transcriptome induced by ERK. In addition to showing that the HOXB8 protein controls the transcriptional responsiveness to ERK oncogenic signaling, our study identified new downstream targets of ERK oncogenic activation in an in vivo context that could provide clues for therapeutic strategies.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Proteínas de Homeodomínio/metabolismo , MAP Quinase Quinase 1/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neoplasias/patologia , Animais , Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Embrião de Galinha , Galinhas , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Humanos , MAP Quinase Quinase 1/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Neoplasias/etiologia , Neoplasias/metabolismo , Prognóstico , Taxa de Sobrevida , Transcriptoma
6.
J Enzyme Inhib Med Chem ; 36(1): 1715-1731, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34425716

RESUMO

Hippo signalling pathway plays a crucial role in tumorigenesis and cancer progression. In this work, we identified an N-aryl sulphonamide-quinazoline derivative, compound 9i as an anti-gastric cancer agent, which exhibited potent antiproliferative ability with IC50 values of 0.36 µM (MGC-803 cells), 0.70 µM (HCT-116 cells), 1.04 µM (PC-3 cells), and 0.81 µM (MCF-7 cells), respectively and inhibited YAP activity by the activation of p-LATS. Compound 9i was effective in suppressing MGC-803 xenograft tumour growth in nude mice without obvious toxicity and significantly down-regulated the expression of YAP in vivo. Compound 9i arrested cells in the G2/M phase, induced intrinsic apoptosis, and inhibited cell colony formation in MGC-803 and SGC-7901 cells. Therefore, compound 9i is to be reported as an anti-gastric cancer agent via activating the Hippo signalling pathway and might help foster a new strategy for the cancer treatment by activating the Hippo signalling pathway regulatory function to inhibit the activity of YAP.


Assuntos
Antineoplásicos/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Quinazolinas/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Sulfonamidas/farmacologia , Animais , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Nus , Estrutura Molecular , Quinazolinas/síntese química , Transdução de Sinais , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361004

RESUMO

This article reviews evidence suggesting that a common mechanism of initiation leads to the development of many prevalent types of cancer. Endogenous estrogens, in the form of catechol estrogen-3,4-quinones, play a central role in this pathway of cancer initiation. The catechol estrogen-3,4-quinones react with specific purine bases in DNA to form depurinating estrogen-DNA adducts that generate apurinic sites. The apurinic sites can then lead to cancer-causing mutations. The process of cancer initiation has been demonstrated using results from test tube reactions, cultured mammalian cells, and human subjects. Increased amounts of estrogen-DNA adducts are found not only in people with several different types of cancer but also in women at high risk for breast cancer, indicating that the formation of adducts is on the pathway to cancer initiation. Two compounds, resveratrol, and N-acetylcysteine, are particularly good at preventing the formation of estrogen-DNA adducts in humans and are, thus, potential cancer-prevention compounds.


Assuntos
Acetilcisteína/farmacologia , Carcinogênese/efeitos dos fármacos , Estradiol/farmacologia , Estrona/farmacologia , Quinonas/farmacologia , Resveratrol/farmacologia , Animais , Antioxidantes/farmacologia , Carcinogênese/genética , Adutos de DNA , Estradiol/toxicidade , Estrogênios/farmacologia , Estrogênios/toxicidade , Estrona/toxicidade , Humanos , Quinonas/toxicidade
8.
Nat Commun ; 12(1): 5056, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417458

RESUMO

Melanoma cells rely on developmental programs during tumor initiation and progression. Here we show that the embryonic stem cell (ESC) factor Sall4 is re-expressed in the Tyr::NrasQ61K; Cdkn2a-/- melanoma model and that its expression is necessary for primary melanoma formation. Surprisingly, while Sall4 loss prevents tumor formation, it promotes micrometastases to distant organs in this melanoma-prone mouse model. Transcriptional profiling and in vitro assays using human melanoma cells demonstrate that SALL4 loss induces a phenotype switch and the acquisition of an invasive phenotype. We show that SALL4 negatively regulates invasiveness through interaction with the histone deacetylase (HDAC) 2 and direct co-binding to a set of invasiveness genes. Consequently, SALL4 knock down, as well as HDAC inhibition, promote the expression of an invasive signature, while inhibition of histone acetylation partially reverts the invasiveness program induced by SALL4 loss. Thus, SALL4 appears to regulate phenotype switching in melanoma through an HDAC2-mediated mechanism.


Assuntos
Epigênese Genética , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Fator de Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Animais , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Adesão Celular/genética , Linhagem Celular Tumoral , Linhagem da Célula , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 2/metabolismo , Histonas/metabolismo , Humanos , Melanócitos/metabolismo , Melanócitos/patologia , Camundongos Nus , Camundongos Transgênicos , Invasividade Neoplásica , Micrometástase de Neoplasia , Ligação Proteica , Carga Tumoral
9.
Mol Biol (Mosk) ; 55(4): 531-542, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34432772

RESUMO

Small SCP phosphatases CTDSP1, CTDSP2, and CTDSPL specifically dephosphorylate serine and threonine residues in protein molecules. The enzymes are involved in regulating activity of RNA polymerase II at the transition from transcription initiation to elongation, regulating expression of neuron-specific genes, and activating the key cell-cycle protein pRb at the G1/S boundary. In addition, the substrates of SCP phosphatases include SMAD transcription modulators; AKT1 protein kinase, which regulates the cell cycle, apoptosis, and angiogenesis; the TWIST1 and c-MYC transcription factors; Ras family proteins, which are involved in signaling pathways regulating the cell growth and apoptosis; CDCA3, which is associated with cell division; the cyclin-dependent kinase inhibitor p21; and the promyelocytic leukemia protein (PML), which is involved in regulation of the tumor suppressors p53, PTEN, and mTOR. Dysfunction or inactivation of SCP phosphatases leads to various diseases, including cancer. Recently the increase in interest to SCP phosphatases is due to their their tumor growth-inhibiting properties or role in the development of malignant tumors of various etiology and localization. The review discusses the properties of SCP phosphatases and their role in oncogenesis. Understanding the functions of SCP phosphatases and their regulatory mechanisms can be useful in searching for efficient targets for tumor therapy.


Assuntos
Carcinogênese , Neoplasias , Carcinogênese/genética , Ciclo Celular , Proteínas de Ciclo Celular , Transformação Celular Neoplásica/genética , Humanos , Neoplasias/genética , Fosfoproteínas Fosfatases/genética
10.
Adv Exp Med Biol ; 1288: 69-93, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34453732

RESUMO

Cancer/testis (CT) antigens are proteins aberrantly overexpressed in various tumorigenic cells, but they can also be normally expressed in the mammalian germline. Most CT antigens are highly immunogenic and known to be involved in cancer cell proliferation and tumor metastasis. A recent genome-wide analysis systematically identified CT antigen expression in 19 cancer types, significantly expanding the repertoire of CT antigens by 5-fold, from over 200 to approximately 1000. However, their function and regulation in tumorigenesis remain poorly understood. The shared functional characteristics between germ cells and cancer cells, if methodically defined, offer a unique gateway to understanding the regulation of CT antigens in cancers by studying gametogenesis. Nonetheless, such studies also provide insightful information on the role of CT antigens in spermatogenesis. Herein, we analyzed publicly available next generation sequencing datasets generated from normal adult testes in rodents, primordial germ cells and cancer samples across a series of published studies and databases. Based on these analyses, we report that a subset of CT antigens belonged to the core fitness gene family. Furthermore, super-enhancers both in normal testes and various cancers controlled specific CT antigens. We found that DNA methylation of CT antigens, such as TEX101 and TAF7L, was inversely correlated with their expression in both normal primordial germ cells and various cancers, which was mediated at least partly by DNA methyltransferase1 (DNMT1). By analyzing data from a testis knockout model, we showed that TAF7L could further influence the expression of additional CT antigens, which also held true in tumors. These findings not only confirmed the previous notion that CT antigens regulate cancer dynamics, but also showed that understanding the regulation of CT antigens during gametogenesis can offer new insights for cancer research.


Assuntos
Antígenos de Neoplasias , Testículo , Animais , Antígenos de Neoplasias/genética , Carcinogênese/genética , Células Germinativas , Masculino , Roedores
11.
Nat Commun ; 12(1): 4753, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362903

RESUMO

Gallbladder carcinoma is the most common cancer of the biliary tract with dismal survival largely due to delayed diagnosis. Biliary tract intraepithelial neoplasia (BilIN) is the common benign tumor that is suspected to be precancerous lesions. However, the genetic and evolutionary relationships between BilIN and carcinoma remain unclear. Here we perform whole-exome sequencing of coexisting low-grade BilIN (adenoma), high-grade BilIN, and carcinoma lesions, and normal tissues from the same patients. We identify aging as a major factor contributing to accumulated mutations and a critical role of CTNNB1 mutations in these tumors. We reveal two distinct carcinoma evolutionary paths: carcinoma can either diverge earlier and evolve more independently or form through the classic adenoma/dysplasia-carcinoma sequence model. Our analysis suggests that extensive loss-of-heterozygosity and mutation events in the initial stage tend to result in a cancerous niche, leading to the subsequent BilIN-independent path. These results reframes our understanding of tumor transformation and the evolutionary trajectory of carcinogenesis in the gallbladder, laying a foundation for the early diagnosis and effective treatment of gallbladder cancer.


Assuntos
Evolução Biológica , Carcinoma/genética , Neoplasias da Vesícula Biliar/genética , Genômica , Neoplasias/genética , Carcinogênese/genética , Carcinoma in Situ/patologia , Feminino , Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Filogenia , Lesões Pré-Cancerosas/genética
12.
Indian J Med Res ; 153(4): 431-445, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34380789

RESUMO

Several studies have shown an inverse relationship between acute infections and cancer development. On the other hand, there is a growing evidence that chronic infections may contribute significantly to the carcinogenesis. Factors responsible for increased susceptibility to infections may include modifications of normal defence mechanisms or impairment of host immunity due to altered immune function, genetic polymorphisms, ageing and malnourishment. Studies have demonstrated that children exposed to febrile infectious diseases show a subsequent reduced risk for ovarian cancer, melanoma and many other cancers, while common acute infections in adults are associated with reduced risks for melanoma, glioma, meningioma and multiple cancers. Chronic inflammation associated with certain infectious diseases has been suggested as a cause for the development of tumours. Mechanisms of carcinogenesis due to infections include cell proliferation and DNA replication by mitogen-activated protein kinase pathway, production of toxins that affect the cell cycle and lead to abnormal cell growth and inhibition of apoptosis. This review was aimed to summarize the available evidence on acute infections as a means of cancer prevention and on the role of chronic infections in the development and progression of cancer.


Assuntos
Carcinogênese , Melanoma , Apoptose , Ciclo Celular , Proliferação de Células , Humanos
13.
Int J Mol Sci ; 22(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445633

RESUMO

Caspases, a family of cysteine-aspartic proteases, have an established role as critical components in the activation and initiation of apoptosis. Alongside this a variety of non-apoptotic caspase functions in proliferation, differentiation, cellular plasticity and cell migration have been reported. The activity level and context are important factors in determining caspase function. As a consequence of their critical role in apoptosis and beyond, caspases are uniquely situated to have pathological roles, including in cancer. Altered caspase function is a common trait in a variety of cancers, with apoptotic evasion defined as a "hallmark of cancer". However, the role that caspases play in cancer is much more complex, acting both to prevent and to promote tumourigenesis. This review focuses on the major findings in Drosophila on the dual role of caspases in tumourigenesis. This has major implications for cancer treatments, including chemotherapy and radiotherapy, with the activation of apoptosis being the end goal. However, such treatments may inadvertently have adverse effects on promoting tumour progression and acerbating the cancer. A comprehensive understanding of the dual role of caspases will aid in the development of successful cancer therapeutic approaches.


Assuntos
Apoptose , Carcinogênese , Caspases/metabolismo , Neoplasias/patologia , Animais , Drosophila , Humanos , Neoplasias/enzimologia , Neoplasias/etiologia , Neoplasias/prevenção & controle
14.
Nat Commun ; 12(1): 4841, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404770

RESUMO

RAS proteins are GTPases that lie upstream of a signaling network impacting cell fate determination. How cells integrate RAS activity to balance proliferation and cellular senescence is still incompletely characterized. Here, we identify ZNF768 as a phosphoprotein destabilized upon RAS activation. We report that ZNF768 depletion impairs proliferation and induces senescence by modulating the expression of key cell cycle effectors and established p53 targets. ZNF768 levels decrease in response to replicative-, stress- and oncogene-induced senescence. Interestingly, ZNF768 overexpression contributes to bypass RAS-induced senescence by repressing the p53 pathway. Furthermore, we show that ZNF768 interacts with and represses p53 phosphorylation and activity. Cancer genomics and immunohistochemical analyses reveal that ZNF768 is often amplified and/or overexpressed in tumors, suggesting that cells could use ZNF768 to bypass senescence, sustain proliferation and promote malignant transformation. Thus, we identify ZNF768 as a protein linking oncogenic signaling to the control of cell fate decision and proliferation.


Assuntos
Senescência Celular/genética , Genes ras/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Carcinogênese , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Transformação Celular Neoplásica , Replicação do DNA , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Genômica , Células HeLa , Humanos , Oncogenes , Fenótipo , Fosfoproteínas , Fosforilação , Repressão Psicológica , Transdução de Sinais , Proteínas ras/genética
15.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360777

RESUMO

Hepatocellular carcinoma (HCC) develops almost entirely in the presence of chronic inflammation. Chronic hepatitis B virus (HBV) infection with recurrent immune-mediated liver damage ultimately leads to cirrhosis and HCC. It is widely accepted that HBV infection induces the dysfunction of the innate and adaptive immune responses that engage various immune cells. Natural killer (NK) cells are associated with early antiviral and antitumor properties. On the other hand, inflammatory cells release various cytokines and chemokines that may promote HCC tumorigenesis. Moreover, immunosuppressive cells such as regulatory T cells (Treg) and myeloid-derived suppressive cells play a critical role in hepatocarcinogenesis. HBV-specific CD8+ T cells have been identified as pivotal players in antiviral responses, whilst extremely activated CD8+ T cells induce enormous inflammatory responses, and chronic inflammation can facilitate hepatocarcinogenesis. Controlling and maintaining the balance in the immune system is an important aspect in the management of HBV-related HCC. We conducted a review of the current knowledge on the immunopathogenesis of HBV-induced inflammation and the role of such immune activation in the tumorigenesis of HCC based on the recent studies on innate and adaptive immune cell dysfunction in HBV-related HCC.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T CD8-Positivos/patologia , Carcinogênese/imunologia , Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Hepatite B Crônica/patologia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Linfócitos T Reguladores/patologia
16.
Mol Cell ; 81(16): 3339-3355.e8, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34352206

RESUMO

Cancer cells selectively promote translation of specific oncogenic transcripts to facilitate cancer survival and progression, but the underlying mechanisms are poorly understood. Here, we find that N7-methylguanosine (m7G) tRNA modification and its methyltransferase complex components, METTL1 and WDR4, are significantly upregulated in intrahepatic cholangiocarcinoma (ICC) and associated with poor prognosis. We further reveal the critical role of METTL1/WDR4 in promoting ICC cell survival and progression using loss- and gain-of-function assays in vitro and in vivo. Mechanistically, m7G tRNA modification selectively regulates the translation of oncogenic transcripts, including cell-cycle and epidermal growth factor receptor (EGFR) pathway genes, in m7G-tRNA-decoded codon-frequency-dependent mechanisms. Moreover, using overexpression and knockout mouse models, we demonstrate the crucial oncogenic function of Mettl1-mediated m7G tRNA modification in promoting ICC tumorigenesis and progression in vivo. Our study uncovers the important physiological function and mechanism of METTL1-mediated m7G tRNA modification in the regulation of oncogenic mRNA translation and cancer progression.


Assuntos
Colangiocarcinoma/genética , Proteínas de Ligação ao GTP/genética , Metiltransferases/genética , Biossíntese de Proteínas , Animais , Carcinogênese/genética , Colangiocarcinoma/patologia , Progressão da Doença , Receptores ErbB/genética , Guanosina/análogos & derivados , Guanosina/genética , Humanos , Camundongos , Processamento Pós-Transcricional do RNA/genética , RNA Mensageiro/genética , RNA de Transferência/genética
17.
Mol Cell ; 81(16): 3323-3338.e14, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34352207

RESUMO

The emerging "epitranscriptomics" field is providing insights into the biological and pathological roles of different RNA modifications. The RNA methyltransferase METTL1 catalyzes N7-methylguanosine (m7G) modification of tRNAs. Here we find METTL1 is frequently amplified and overexpressed in cancers and is associated with poor patient survival. METTL1 depletion causes decreased abundance of m7G-modified tRNAs and altered cell cycle and inhibits oncogenicity. Conversely, METTL1 overexpression induces oncogenic cell transformation and cancer. Mechanistically, we find increased abundance of m7G-modified tRNAs, in particular Arg-TCT-4-1, and increased translation of mRNAs, including cell cycle regulators that are enriched in the corresponding AGA codon. Accordingly, Arg-TCT expression is elevated in many tumor types and is associated with patient survival, and strikingly, overexpression of this individual tRNA induces oncogenic transformation. Thus, METTL1-mediated tRNA modification drives oncogenic transformation through a remodeling of the mRNA "translatome" to increase expression of growth-promoting proteins and represents a promising anti-cancer target.


Assuntos
Carcinogênese/genética , Metiltransferases/genética , Neoplasias/genética , tRNA Metiltransferases/genética , Guanosina/análogos & derivados , Guanosina/genética , Humanos , Metilação , Neoplasias/patologia , Oncogenes/genética , Processamento Pós-Transcricional do RNA/genética , RNA Mensageiro/genética , RNA de Transferência/genética
18.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360879

RESUMO

Globally, breast cancer has remained the most commonly diagnosed cancer and the leading cause of cancer death among women. Breast cancer is a highly heterogeneous and phenotypically diverse group of diseases, which require different selection of treatments. Breast cancer stem cells (BCSCs), a small subset of cancer cells with stem cell-like properties, play essential roles in breast cancer progression, recurrence, metastasis, chemoresistance and treatments. Epigenetics is defined as inheritable changes in gene expression without alteration in DNA sequence. Epigenetic regulation includes DNA methylation and demethylation, as well as histone modifications. Aberrant epigenetic regulation results in carcinogenesis. In this review, the mechanism of epigenetic regulation involved in carcinogenesis, therapeutic resistance and metastasis of BCSCs will be discussed, and finally, the therapies targeting these biomarkers will be presented.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Carcinogênese/genética , Epigênese Genética , Terapia de Alvo Molecular/métodos , Células-Tronco Neoplásicas/metabolismo , Animais , Biomarcadores Tumorais/genética , Neoplasias da Mama/metabolismo , Carcinogênese/metabolismo , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Código das Histonas/efeitos dos fármacos , Código das Histonas/genética , Humanos
19.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445578

RESUMO

The phenomenon of how oncogenes and tumor-suppressor mutations can synergize to promote tumor fitness and cancer progression can be studied in relatively simple animal model systems such as Drosophila melanogaster. Almost two decades after the landmark discovery of cooperative oncogenesis between oncogenic RasV12 and the loss of the tumor suppressor scribble in flies, this and other tumor models have provided new concepts and findings in cancer biology that has remarkable parallels and relevance to human cancer. Here we review findings using the RasV12; scrib-/- tumor model and how it has contributed to our understanding of how these initial simple genetic insults cooperate within the tumor cell to set in motion the malignant transformation program leading to tumor growth through cell growth, cell survival and proliferation, dismantling of cell-cell interactions, degradation of basement membrane and spreading to other organs. Recent findings have demonstrated that cooperativity goes beyond cell intrinsic mechanisms as the tumor interacts with the immediate cells of the microenvironment, the immune system and systemic organs to eventually facilitate malignant progression.


Assuntos
Carcinogênese , Proteínas de Membrana/metabolismo , Mutação , Neoplasias/patologia , Microambiente Tumoral , Proteínas Supressoras de Tumor/metabolismo , Proteínas ras/metabolismo , Animais , Humanos , Proteínas de Membrana/genética , Neoplasias/etiologia , Neoplasias/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/genética , Proteínas ras/genética
20.
Am J Hum Genet ; 108(9): 1590-1610, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34390653

RESUMO

Our study investigated the underlying mechanism for the 14q24 renal cell carcinoma (RCC) susceptibility risk locus identified by a genome-wide association study (GWAS). The sentinel single-nucleotide polymorphism (SNP), rs4903064, at 14q24 confers an allele-specific effect on expression of the double PHD fingers 3 (DPF3) of the BAF SWI/SNF complex as assessed by massively parallel reporter assay, confirmatory luciferase assays, and eQTL analyses. Overexpression of DPF3 in renal cell lines increases growth rates and alters chromatin accessibility and gene expression, leading to inhibition of apoptosis and activation of oncogenic pathways. siRNA interference of multiple DPF3-deregulated genes reduces growth. Our results indicate that germline variation in DPF3, a component of the BAF complex, part of the SWI/SNF complexes, can lead to reduced apoptosis and activation of the STAT3 pathway, both critical in RCC carcinogenesis. In addition, we show that altered DPF3 expression in the 14q24 RCC locus could influence the effectiveness of immunotherapy treatment for RCC by regulating tumor cytokine secretion and immune cell activation.


Assuntos
Carcinoma de Células Renais/genética , Cromossomos Humanos Par 14 , Proteínas de Ligação a DNA/genética , Loci Gênicos , Neoplasias Renais/genética , Fator de Transcrição STAT3/genética , Fatores de Transcrição/genética , Carcinogênese/genética , Carcinogênese/imunologia , Carcinogênese/patologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/terapia , Linhagem Celular Tumoral , Cromatina/química , Cromatina/imunologia , Montagem e Desmontagem da Cromatina/imunologia , Citocinas/genética , Citocinas/imunologia , Proteínas de Ligação a DNA/imunologia , Regulação da Expressão Gênica , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunoterapia/métodos , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Neoplasias Renais/terapia , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT3/imunologia , Linfócitos T Citotóxicos , Fatores de Transcrição/imunologia
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