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1.
Cell ; 184(22): 5559-5576.e19, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34678143

RESUMO

Glucose consumption is generally increased in tumor cells to support tumor growth. Interestingly, we report that glycogen accumulation is a key initiating oncogenic event during liver malignant transformation. We found that glucose-6-phosphatase (G6PC) catalyzing the last step of glycogenolysis is frequently downregulated to augment glucose storage in pre-malignant cells. Accumulated glycogen undergoes liquid-liquid phase separation, which results in the assembly of the Laforin-Mst1/2 complex and consequently sequesters Hippo kinases Mst1/2 in glycogen liquid droplets to relieve their inhibition on Yap. Moreover, G6PC or another glycogenolysis enzyme-liver glycogen phosphorylase (PYGL) deficiency in both human and mice results in glycogen storage disease along with liver enlargement and tumorigenesis in a Yap-dependent manner. Consistently, elimination of glycogen accumulation abrogates liver growth and cancer incidence, whereas increasing glycogen storage accelerates tumorigenesis. Thus, we concluded that cancer-initiating cells adapt a glycogen storing mode, which blocks Hippo signaling through glycogen phase separation to augment tumor incidence.


Assuntos
Carcinogênese/metabolismo , Carcinogênese/patologia , Glicogênio/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular , Modelos Animais de Doenças , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glucose-6-Fosfatase/metabolismo , Glicogênio Fosforilase/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Via de Sinalização Hippo , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Transição de Fase , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Serina-Treonina Quinase 3/metabolismo , Proteínas de Sinalização YAP/metabolismo
2.
Nat Immunol ; 22(11): 1391-1402, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34686865

RESUMO

Epithelial cells have an ability termed 'cell competition', which is an immune surveillance-like function that extrudes precancerous cells from the epithelial layer, leading to apoptosis and clearance. However, it remains unclear how epithelial cells recognize and extrude transformed cells. Here, we discovered that a PirB family protein, leukocyte immunoglobulin-like receptor B3 (LILRB3), which is expressed on non-transformed epithelial cells, recognizes major histocompatibility complex class I (MHC class I) that is highly expressed on transformed cells. MHC class I interaction with LILRB3 expressed on normal epithelial cells triggers an SHP2-ROCK2 pathway that generates a mechanical force to extrude transformed cells. Removal of transformed cells occurs independently of natural killer (NK) cell or CD8+ cytotoxic T cell-mediated activity. This is a new mechanism in that the immunological ligand-receptor system generates a mechanical force in non-immune epithelial cells to extrude precancerous cells in the same epithelial layer.


Assuntos
Antígenos CD/metabolismo , Apoptose , Competição entre as Células , Células Epiteliais/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias Pulmonares/metabolismo , Lesões Pré-Cancerosas/metabolismo , Receptores Imunológicos/metabolismo , Animais , Antígenos CD/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Cães , Células Epiteliais/imunologia , Células Epiteliais/patologia , Células HaCaT , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Células Madin Darby de Rim Canino , Mecanotransdução Celular , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/imunologia , Lesões Pré-Cancerosas/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Células RAW 264.7 , Receptores Imunológicos/genética , Estresse Mecânico , Quinases Associadas a rho/metabolismo
3.
Nature ; 629(8012): 679-687, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693266

RESUMO

Pancreatic intraepithelial neoplasias (PanINs) are the most common precursors of pancreatic cancer, but their small size and inaccessibility in humans make them challenging to study1. Critically, the number, dimensions and connectivity of human PanINs remain largely unknown, precluding important insights into early cancer development. Here, we provide a microanatomical survey of human PanINs by analysing 46 large samples of grossly normal human pancreas with a machine-learning pipeline for quantitative 3D histological reconstruction at single-cell resolution. To elucidate genetic relationships between and within PanINs, we developed a workflow in which 3D modelling guides multi-region microdissection and targeted and whole-exome sequencing. From these samples, we calculated a mean burden of 13 PanINs per cm3 and extrapolated that the normal intact adult pancreas harbours hundreds of PanINs, almost all with oncogenic KRAS hotspot mutations. We found that most PanINs originate as independent clones with distinct somatic mutation profiles. Some spatially continuous PanINs were found to contain multiple KRAS mutations; computational and in situ analyses demonstrated that different KRAS mutations localize to distinct cell subpopulations within these neoplasms, indicating their polyclonal origins. The extensive multifocality and genetic heterogeneity of PanINs raises important questions about mechanisms that drive precancer initiation and confer differential progression risk in the human pancreas. This detailed 3D genomic mapping of molecular alterations in human PanINs provides an empirical foundation for early detection and rational interception of pancreatic cancer.


Assuntos
Heterogeneidade Genética , Genômica , Imageamento Tridimensional , Neoplasias Pancreáticas , Lesões Pré-Cancerosas , Análise de Célula Única , Adulto , Feminino , Humanos , Masculino , Células Clonais/metabolismo , Células Clonais/patologia , Sequenciamento do Exoma , Aprendizado de Máquina , Mutação , Pâncreas/anatomia & histologia , Pâncreas/citologia , Pâncreas/metabolismo , Pâncreas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Fluxo de Trabalho , Progressão da Doença , Detecção Precoce de Câncer , Oncogenes/genética
4.
Nature ; 627(8004): 656-663, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418883

RESUMO

Understanding the cellular processes that underlie early lung adenocarcinoma (LUAD) development is needed to devise intervention strategies1. Here we studied 246,102 single epithelial cells from 16 early-stage LUADs and 47 matched normal lung samples. Epithelial cells comprised diverse normal and cancer cell states, and diversity among cancer cells was strongly linked to LUAD-specific oncogenic drivers. KRAS mutant cancer cells showed distinct transcriptional features, reduced differentiation and low levels of aneuploidy. Non-malignant areas surrounding human LUAD samples were enriched with alveolar intermediate cells that displayed elevated KRT8 expression (termed KRT8+ alveolar intermediate cells (KACs) here), reduced differentiation, increased plasticity and driver KRAS mutations. Expression profiles of KACs were enriched in lung precancer cells and in LUAD cells and signified poor survival. In mice exposed to tobacco carcinogen, KACs emerged before lung tumours and persisted for months after cessation of carcinogen exposure. Moreover, they acquired Kras mutations and conveyed sensitivity to targeted KRAS inhibition in KAC-enriched organoids derived from alveolar type 2 (AT2) cells. Last, lineage-labelling of AT2 cells or KRT8+ cells following carcinogen exposure showed that KACs are possible intermediates in AT2-to-tumour cell transformation. This study provides new insights into epithelial cell states at the root of LUAD development, and such states could harbour potential targets for prevention or intervention.


Assuntos
Adenocarcinoma de Pulmão , Diferenciação Celular , Células Epiteliais , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Aneuploidia , Carcinógenos/toxicidade , Células Epiteliais/classificação , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Organoides/efeitos dos fármacos , Organoides/metabolismo , Lesões Pré-Cancerosas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Taxa de Sobrevida , Produtos do Tabaco/efeitos adversos , Produtos do Tabaco/toxicidade
5.
Nat Immunol ; 18(2): 236-245, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28024152

RESUMO

Toll-like receptor (TLR) activation contributes to premalignant hematologic conditions, such as myelodysplastic syndromes (MDS). TRAF6, a TLR effector with ubiquitin (Ub) ligase activity, is overexpressed in MDS hematopoietic stem/progenitor cells (HSPCs). We found that TRAF6 overexpression in mouse HSPC results in impaired hematopoiesis and bone marrow failure. Using a global Ub screen, we identified hnRNPA1, an RNA-binding protein and auxiliary splicing factor, as a substrate of TRAF6. TRAF6 ubiquitination of hnRNPA1 regulated alternative splicing of Arhgap1, which resulted in activation of the GTP-binding Rho family protein Cdc42 and accounted for hematopoietic defects in TRAF6-expressing HSPCs. These results implicate Ub signaling in coordinating RNA processing by TLR pathways during an immune response and in premalignant hematologic diseases, such as MDS.


Assuntos
Células-Tronco Hematopoéticas/fisiologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Síndromes Mielodisplásicas/imunologia , Lesões Pré-Cancerosas/imunologia , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/metabolismo , Ubiquitinação , Animais , Autoimunidade , Células Cultivadas , Hematopoese/genética , Ribonucleoproteína Nuclear Heterogênea A1 , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais/genética , Fator 6 Associado a Receptor de TNF/genética , Receptores Toll-Like/metabolismo , Ubiquitinação/genética , Proteína cdc42 de Ligação ao GTP/metabolismo
6.
Nature ; 618(7964): 383-393, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37258665

RESUMO

The earliest events during human tumour initiation, although poorly characterized, may hold clues to malignancy detection and prevention1. Here we model occult preneoplasia by biallelic inactivation of TP53, a common early event in gastric cancer, in human gastric organoids. Causal relationships between this initiating genetic lesion and resulting phenotypes were established using experimental evolution in multiple clonally derived cultures over 2 years. TP53 loss elicited progressive aneuploidy, including copy number alterations and structural variants prevalent in gastric cancers, with evident preferred orders. Longitudinal single-cell sequencing of TP53-deficient gastric organoids similarly indicates progression towards malignant transcriptional programmes. Moreover, high-throughput lineage tracing with expressed cellular barcodes demonstrates reproducible dynamics whereby initially rare subclones with shared transcriptional programmes repeatedly attain clonal dominance. This powerful platform for experimental evolution exposes stringent selection, clonal interference and a marked degree of phenotypic convergence in premalignant epithelial organoids. These data imply predictability in the earliest stages of tumorigenesis and show evolutionary constraints and barriers to malignant transformation, with implications for earlier detection and interception of aggressive, genome-instable tumours.


Assuntos
Transformação Celular Neoplásica , Evolução Clonal , Lesões Pré-Cancerosas , Seleção Genética , Neoplasias Gástricas , Humanos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Evolução Clonal/genética , Instabilidade Genômica , Mutação , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Organoides/metabolismo , Organoides/patologia , Aneuploidia , Variações do Número de Cópias de DNA , Análise de Célula Única , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Progressão da Doença , Linhagem da Célula
7.
CA Cancer J Clin ; 71(6): 505-526, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34499351

RESUMO

Despite being highly preventable, cervical cancer is the fourth most common cancer and cause of cancer death in women globally. In low-income countries, cervical cancer is often the leading cause of cancer-related morbidity and mortality. Women living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome are at a particularly high risk of cervical cancer because of an impaired immune response to human papillomavirus, the obligate cause of virtually all cervical cancers. Globally, approximately 1 in 20 cervical cancers is attributable to HIV; in sub-Saharan Africa, approximately 1 in 5 cervical cancers is due to HIV. Here, the authors provide a critical appraisal of the evidence to date on the impact of HIV disease on cervical cancer risk, describe key methodologic issues, and frame the key outstanding research questions, especially as they apply to ongoing global efforts for prevention and control of cervical cancer. Expanded efforts to integrate HIV care with cervical cancer prevention and control, and vice versa, could assist the global effort to eliminate cervical cancer as a public health problem.


Assuntos
Infecções por HIV/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Detecção Precoce de Câncer , Feminino , Humanos , Hospedeiro Imunocomprometido , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Lesões Pré-Cancerosas/terapia , Prevenção Primária , Prevenção Secundária
8.
N Engl J Med ; 390(11): 973-983, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38477985

RESUMO

BACKGROUND: Colorectal cancer is the third most diagnosed cancer in adults in the United States. Early detection could prevent more than 90% of colorectal cancer-related deaths, yet more than one third of the screening-eligible population is not up to date with screening despite multiple available tests. A blood-based test has the potential to improve screening adherence, detect colorectal cancer earlier, and reduce colorectal cancer-related mortality. METHODS: We assessed the performance characteristics of a cell-free DNA (cfDNA) blood-based test in a population eligible for colorectal cancer screening. The coprimary outcomes were sensitivity for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions) relative to screening colonoscopy. The secondary outcome was sensitivity to detect advanced precancerous lesions. RESULTS: The clinical validation cohort included 10,258 persons, 7861 of whom met eligibility criteria and were evaluable. A total of 83.1% of the participants with colorectal cancer detected by colonoscopy had a positive cfDNA test and 16.9% had a negative test, which indicates a sensitivity of the cfDNA test for detection of colorectal cancer of 83.1% (95% confidence interval [CI], 72.2 to 90.3). Sensitivity for stage I, II, or III colorectal cancer was 87.5% (95% CI, 75.3 to 94.1), and sensitivity for advanced precancerous lesions was 13.2% (95% CI, 11.3 to 15.3). A total of 89.6% of the participants without any advanced colorectal neoplasia (colorectal cancer or advanced precancerous lesions) identified on colonoscopy had a negative cfDNA blood-based test, whereas 10.4% had a positive cfDNA blood-based test, which indicates a specificity for any advanced neoplasia of 89.6% (95% CI, 88.8 to 90.3). Specificity for negative colonoscopy (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0 to 90.7). CONCLUSIONS: In an average-risk screening population, this cfDNA blood-based test had 83% sensitivity for colorectal cancer, 90% specificity for advanced neoplasia, and 13% sensitivity for advanced precancerous lesions. (Funded by Guardant Health; ECLIPSE ClinicalTrials.gov number, NCT04136002.).


Assuntos
Ácidos Nucleicos Livres , Neoplasias Colorretais , Detecção Precoce de Câncer , Programas de Rastreamento , Lesões Pré-Cancerosas , Adulto , Humanos , Ácidos Nucleicos Livres/sangue , Colonoscopia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/métodos , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/diagnóstico , Programas de Rastreamento/métodos , Sensibilidade e Especificidade
9.
N Engl J Med ; 390(11): 984-993, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38477986

RESUMO

BACKGROUND: A next-generation multitarget stool DNA test, including assessments of DNA molecular markers and hemoglobin level, was developed to improve the performance of colorectal cancer screening, primarily with regard to specificity. METHODS: In a prospective study, we evaluated a next-generation multitarget stool DNA test in asymptomatic adults 40 years of age or older who were undergoing screening colonoscopy. The primary outcomes were sensitivity of the test for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions). Advanced precancerous lesions included one or more adenomas or sessile serrated lesions measuring at least 1 cm in the longest dimension, lesions with villous histologic features, and high-grade dysplasia. Secondary objectives included the quantification of sensitivity for advanced precancerous lesions and specificity for nonneoplastic findings or negative colonoscopy and comparison of sensitivities for colorectal cancer and advanced precancerous lesions between the multitarget stool DNA test and a commercially available fecal immunochemical test (FIT). RESULTS: Of 20,176 participants, 98 had colorectal cancer, 2144 had advanced precancerous lesions, 6973 had nonadvanced adenomas, and 10,961 had nonneoplastic findings or negative colonoscopy. With the next-generation test, sensitivity for colorectal cancer was 93.9% (95% confidence interval [CI], 87.1 to 97.7), and specificity for advanced neoplasia was 90.6% (95% CI, 90.1 to 91.0). Sensitivity for advanced precancerous lesions was 43.4% (95% CI, 41.3 to 45.6), and specificity for nonneoplastic findings or negative colonoscopy was 92.7% (95% CI, 92.2 to 93.1). With the FIT, sensitivity was 67.3% (95% CI, 57.1 to 76.5) for colorectal cancer and 23.3% (95% CI, 21.5 to 25.2) for advanced precancerous lesions; specificity was 94.8% (95% CI, 94.4 to 95.1) for advanced neoplasia and 95.7% (95% CI, 95.3 to 96.1) for nonneoplastic findings or negative colonoscopy. As compared with FIT, the next-generation test had superior sensitivity for colorectal cancer (P<0.001) and for advanced precancerous lesions (P<0.001) but had lower specificity for advanced neoplasia (P<0.001). No adverse events occurred. CONCLUSIONS: The next-generation multitarget stool DNA test showed higher sensitivity for colorectal cancer and advanced precancerous lesions than FIT but also showed lower specificity. (Funded by Exact Sciences; BLUE-C ClinicalTrials.gov number, NCT04144738.).


Assuntos
Adenoma , Neoplasias Colorretais , DNA , Detecção Precoce de Câncer , Fezes , Imunoquímica , Lesões Pré-Cancerosas , Adulto , Humanos , Adenoma/diagnóstico , Neoplasias Colorretais/diagnóstico , DNA/análise , Detecção Precoce de Câncer/métodos , Fezes/química , Lesões Pré-Cancerosas/diagnóstico , Estudos Prospectivos , Doenças Assintomáticas , Colonoscopia , Sensibilidade e Especificidade , Testes Imunológicos/métodos , Imunoquímica/métodos
10.
Genes Dev ; 33(3-4): 127-143, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30709901

RESUMO

Originally thought of as a stress response end point, the view of cellular senescence has since evolved into one encompassing a wide range of physiological and pathological functions, including both protumorignic and antitumorigenic features. It has also become evident that senescence is a highly dynamic and heterogenous process. Efforts to reconcile the beneficial and detrimental features of senescence suggest that physiological functions require the transient presence of senescent cells in the tissue microenvironment. Here, we propose the concept of a physiological "senescence life cycle," which has pathological consequences if not executed in its entirety.


Assuntos
Ciclo Celular/fisiologia , Senescência Celular/fisiologia , Neoplasias/fisiopatologia , Microambiente Celular/fisiologia , Epigenômica , Humanos , Lesões Pré-Cancerosas/fisiopatologia , Encurtamento do Telômero
11.
Blood ; 143(22): 2245-2255, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38498034

RESUMO

ABSTRACT: The spectrum of myeloid disorders ranges from aplastic bone marrow failure characterized by an empty bone marrow completely lacking in hematopoiesis to acute myeloid leukemia in which the marrow space is replaced by undifferentiated leukemic blasts. Recent advances in the capacity to sequence bulk tumor population as well as at a single-cell level has provided significant insight into the stepwise process of transformation to acute myeloid leukemia. Using models of progression in the context of germ line predisposition (trisomy 21, GATA2 deficiency, and SAMD9/9L syndrome), premalignant states (clonal hematopoiesis and clonal cytopenia of unknown significance), and myelodysplastic syndrome, we review the mechanisms of progression focusing on the hierarchy of clonal mutation and potential roles of transcription factor alterations, splicing factor mutations, and the bone marrow environment in progression to acute myeloid leukemia. Despite major advances in our understanding, preventing the progression of these disorders or treating them at the acute leukemia phase remains a major area of unmet medical need.


Assuntos
Progressão da Doença , Humanos , Pré-Leucemia/patologia , Pré-Leucemia/genética , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/genética , Animais , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/genética , Mutação , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Transformação Celular Neoplásica/metabolismo
12.
Proc Natl Acad Sci U S A ; 120(31): e2301536120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37487069

RESUMO

Colorectal cancers (CRCs) form a heterogenous group classified into epigenetic and transcriptional subtypes. The basis for the epigenetic subtypes, exemplified by varying degrees of promoter DNA hypermethylation, and its relation to the transcriptional subtypes is not well understood. We link cancer-specific transcription factor (TF) expression alterations to methylation alterations near TF-binding sites at promoter and enhancer regions in CRCs and their premalignant precursor lesions to provide mechanistic insights into the origins and evolution of the CRC molecular subtypes. A gradient of TF expression changes forms a basis for the subtypes of abnormal DNA methylation, termed CpG-island promoter DNA methylation phenotypes (CIMPs), in CRCs and other cancers. CIMP is tightly correlated with cancer-specific hypermethylation at enhancers, which we term CpG-enhancer methylation phenotype (CEMP). Coordinated promoter and enhancer methylation appears to be driven by downregulation of TFs with common binding sites at the hypermethylated enhancers and promoters. The altered expression of TFs related to hypermethylator subtypes occurs early during CRC development, detectable in premalignant adenomas. TF-based profiling further identifies patients with worse overall survival. Importantly, altered expression of these TFs discriminates the transcriptome-based consensus molecular subtypes (CMS), thus providing a common basis for CIMP and CMS subtypes.


Assuntos
Neoplasias Colorretais , Lesões Pré-Cancerosas , Humanos , Fatores de Transcrição , Regulação da Expressão Gênica , Metilação de DNA , Epigênese Genética
13.
Proc Natl Acad Sci U S A ; 120(10): e2211937120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848578

RESUMO

The vast majority of human pancreatic ductal adenocarcinomas (PDACs) harbor TP53 mutations, underscoring p53's critical role in PDAC suppression. PDAC can arise when pancreatic acinar cells undergo acinar-to-ductal metaplasia (ADM), giving rise to premalignant pancreatic intraepithelial neoplasias (PanINs), which finally progress to PDAC. The occurrence of TP53 mutations in late-stage PanINs has led to the idea that p53 acts to suppress malignant transformation of PanINs to PDAC. However, the cellular basis for p53 action during PDAC development has not been explored in detail. Here, we leverage a hyperactive p53 variant-p5353,54-which we previously showed is a more robust PDAC suppressor than wild-type p53, to elucidate how p53 acts at the cellular level to dampen PDAC development. Using both inflammation-induced and KRASG12D-driven PDAC models, we find that p5353,54 both limits ADM accumulation and suppresses PanIN cell proliferation and does so more effectively than wild-type p53. Moreover, p5353,54 suppresses KRAS signaling in PanINs and limits effects on the extracellular matrix (ECM) remodeling. While p5353,54 has highlighted these functions, we find that pancreata in wild-type p53 mice similarly show less ADM, as well as reduced PanIN cell proliferation, KRAS signaling, and ECM remodeling relative to Trp53-null mice. We find further that p53 enhances chromatin accessibility at sites controlled by acinar cell identity transcription factors. These findings reveal that p53 acts at multiple stages to suppress PDAC, both by limiting metaplastic transformation of acini and by dampening KRAS signaling in PanINs, thus providing key new understanding of p53 function in PDAC.


Assuntos
Neoplasias Pancreáticas , Lesões Pré-Cancerosas , Humanos , Animais , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Neoplasias Pancreáticas/genética , Pâncreas , Metaplasia , Camundongos Knockout
14.
Annu Rev Med ; 74: 249-260, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36450282

RESUMO

Aging is associated with increased mutational burden in every tissue studied. Occasionally, fitness-increasing mutations will arise, leading to stem cell clonal expansion. This process occurs in several tissues but has been best studied in blood. Clonal hematopoiesis is associated with an increased risk of blood cancers, such as acute myeloid leukemia, which result if additional cooperating mutations occur. Surprisingly, it is also associated with an increased risk of nonmalignant diseases, such as atherosclerotic cardiovascular disease. This may be due to enhanced inflammation in mutated innate immune cells, which could be targeted clinically with anti-inflammatory drugs. Recent studies have uncovered other factors that predict poor outcomes in patients with clonal hematopoiesis, such as size of the mutant clone, mutated driver genes, and epigenetic aging. Though clonality is inevitable and largely a function of time, recent work has shown that inherited genetic variation can also influence this process. Clonal hematopoiesis provides a paradigm for understanding how age-related changes in tissue stem cell composition and function influence human health.


Assuntos
Neoplasias Hematológicas , Lesões Pré-Cancerosas , Humanos , Hematopoiese Clonal/genética , Hematopoese/genética , Neoplasias Hematológicas/genética , Envelhecimento/genética , Lesões Pré-Cancerosas/patologia , Mutação/genética
15.
N Engl J Med ; 386(24): 2273-2282, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35704479

RESUMO

BACKGROUND: The incidence of anal cancer is substantially higher among persons living with the human immunodeficiency virus (HIV) than in the general population. Similar to cervical cancer, anal cancer is preceded by high-grade squamous intraepithelial lesions (HSILs). Treatment for cervical HSIL reduces progression to cervical cancer; however, data from prospective studies of treatment for anal HSIL to prevent anal cancer are lacking. METHODS: We conducted a phase 3 trial at 25 U.S. sites. Persons living with HIV who were 35 years of age or older and who had biopsy-proven anal HSIL were randomly assigned, in a 1:1 ratio, to receive either HSIL treatment or active monitoring without treatment. Treatment included office-based ablative procedures, ablation or excision under anesthesia, or the administration of topical fluorouracil or imiquimod. The primary outcome was progression to anal cancer in a time-to-event analysis. Participants in the treatment group were treated until HSIL was completely resolved. All the participants underwent high-resolution anoscopy at least every 6 months; biopsy was also performed for suspected ongoing HSIL in the treatment group, annually in the active-monitoring group, or any time there was concern for cancer. RESULTS: Of 4459 participants who underwent randomization, 4446 (99.7%) were included in the analysis of the time to progression to cancer. With a median follow-up of 25.8 months, 9 cases were diagnosed in the treatment group (173 per 100,000 person-years; 95% confidence interval [CI], 90 to 332) and 21 cases in the active-monitoring group (402 per 100,000 person-years; 95% CI, 262 to 616). The rate of progression to anal cancer was lower in the treatment group than in the active-monitoring group by 57% (95% CI, 6 to 80; P = 0.03 by log-rank test). CONCLUSIONS: Among participants with biopsy-proven anal HSIL, the risk of anal cancer was significantly lower with treatment for anal HSIL than with active monitoring. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT02135419.).


Assuntos
Neoplasias do Ânus , Infecções por HIV , Lesões Pré-Cancerosas , Lesões Intraepiteliais Escamosas , Conduta Expectante , Adulto , Neoplasias do Ânus/etiologia , Neoplasias do Ânus/patologia , Neoplasias do Ânus/prevenção & controle , Neoplasias do Ânus/terapia , Biópsia , Feminino , Infecções por HIV/complicações , Homossexualidade Masculina , Humanos , Masculino , Infecções por Papillomavirus/complicações , Lesões Pré-Cancerosas/etiologia , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/terapia , Estudos Prospectivos , Lesões Intraepiteliais Escamosas/etiologia , Lesões Intraepiteliais Escamosas/patologia , Lesões Intraepiteliais Escamosas/terapia
16.
Gastroenterology ; 166(5): 772-786.e14, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38272100

RESUMO

BACKGROUND & AIMS: Gastric carcinogenesis develops within a sequential carcinogenic cascade from precancerous metaplasia to dysplasia and adenocarcinoma, and oncogenic gene activation can drive the process. Metabolic reprogramming is considered a key mechanism for cancer cell growth and proliferation. However, how metabolic changes contribute to the progression of metaplasia to dysplasia remains unclear. We have examined metabolic dynamics during gastric carcinogenesis using a novel mouse model that induces Kras activation in zymogen-secreting chief cells. METHODS: We generated a Gif-rtTA;TetO-Cre;KrasG12D (GCK) mouse model that continuously induces active Kras expression in chief cells after doxycycline treatment. Histologic examination and imaging mass spectrometry were performed in the GCK mouse stomachs at 2 to 14 weeks after doxycycline treatment. Mouse and human gastric organoids were used for metabolic enzyme inhibitor treatment. The GCK mice were treated with a stearoyl- coenzyme A desaturase (SCD) inhibitor to inhibit the fatty acid desaturation. Tissue microarrays were used to assess the SCD expression in human gastrointestinal cancers. RESULTS: The GCK mice developed metaplasia and high-grade dysplasia within 4 months. Metabolic reprogramming from glycolysis to fatty acid metabolism occurred during metaplasia progression to dysplasia. Altered fatty acid desaturation through SCD produces a novel eicosenoic acid, which fuels dysplastic cell hyperproliferation and survival. The SCD inhibitor killed both mouse and human dysplastic organoids and selectively targeted dysplastic cells in vivo. SCD was up-regulated during carcinogenesis in human gastrointestinal cancers. CONCLUSIONS: Active Kras expression only in gastric chief cells drives the full spectrum of gastric carcinogenesis. Also, oncogenic metabolic rewiring is an essential adaptation for high-energy demand in dysplastic cells.


Assuntos
Metabolismo Energético , Ácidos Graxos , Metaplasia , Organoides , Proteínas Proto-Oncogênicas p21(ras) , Neoplasias Gástricas , Animais , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Humanos , Ácidos Graxos/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Organoides/metabolismo , Camundongos , Modelos Animais de Doenças , Carcinogênese/metabolismo , Carcinogênese/genética , Carcinogênese/patologia , Celulas Principais Gástricas/metabolismo , Celulas Principais Gástricas/patologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Transformação Celular Neoplásica/genética , Camundongos Transgênicos , Glicólise , Adenocarcinoma/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/genética , Progressão da Doença , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/genética
17.
Gastroenterology ; 166(1): 117-131, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37802423

RESUMO

BACKGROUNDS & AIMS: Precancerous metaplasia progression to dysplasia can increase the risk of gastric cancers. However, effective strategies to specifically target these precancerous lesions are currently lacking. To address this, we aimed to identify key signaling pathways that are upregulated during metaplasia progression and critical for stem cell survival and function in dysplasia. METHODS: To assess the response to chemotherapeutic drugs, we used metaplastic and dysplastic organoids derived from Mist1-Kras mice and 20 human precancerous organoid lines established from patients with gastric cancer. Phospho-antibody array analysis and single-cell RNA-sequencing were performed to identify target cell populations and signaling pathways affected by pyrvinium, a putative anticancer drug. Pyrvinium was administered to Mist1-Kras mice to evaluate drug effectiveness in vivo. RESULTS: Although pyrvinium treatment resulted in growth arrest in metaplastic organoids, it induced cell death in dysplastic organoids. Pyrvinium treatment significantly downregulated phosphorylation of ERK and signal transducer and activator of transcription 3 (STAT3) as well as STAT3-target genes. Single-cell RNA-sequencing data analyses revealed that pyrvinium specifically targeted CD133+/CD166+ stem cell populations, as well as proliferating cells in dysplastic organoids. Pyrvinium inhibited metaplasia progression and facilitated the restoration of normal oxyntic glands in Mist1-Kras mice. Furthermore, pyrvinium exhibited suppressive effects on the growth and survival of human organoids with dysplastic features, through simultaneous blocking of the MEK/ERK and STAT3 signaling pathways. CONCLUSIONS: Through its dual blockade of MEK/ERK and STAT3 signaling pathways, pyrvinium can effectively induce growth arrest in metaplasia and cell death in dysplasia. Therefore, our findings suggest that pyrvinium is a promising chemotherapeutic agent for reprogramming the precancerous milieu to prevent gastric cancer development.


Assuntos
Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Camundongos , Animais , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/prevenção & controle , Fator de Transcrição STAT3/metabolismo , Carcinogênese/genética , Carcinogênese/patologia , Hiperplasia , Lesões Pré-Cancerosas/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Metaplasia/patologia , Células-Tronco/metabolismo , RNA
18.
Eur J Immunol ; 54(1): e2350627, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37872778

RESUMO

To calibrate a murine model to study premalignant to malignant multiple myeloma, mice were inoculated with different amounts of myeloma cells, and changes in the immune profile were tracked for over 200 days. The model highlights the development of T-cell exhaustion and suppressor before the appearance of clinical symptoms.


Assuntos
Mieloma Múltiplo , Lesões Pré-Cancerosas , Animais , Camundongos , Mieloma Múltiplo/patologia , Imunidade Celular
19.
Eur J Immunol ; 54(3): e2350662, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38366919

RESUMO

Helicobacter pylori is one of the main predisposing factors for gastric cancer, causing chronic inflammation and proper glands atrophy in the gastric mucosa. Although H. pylori-induced inflammation is a key inducer of precancerous lesions in the gastric mucosa, it remains unclear which precise immune cell subsets are responsible for the progression of H. pylori-induced gastritis. Here, we observed an abundance of CD4+ IL-17A+ FOXP3+ T cells exhibiting a Th17-like phenotype within the microenvironment of H. pylori-induced gastritis. Mechanistically, H. pylori upregulated the expression of IL-6 in Dendritic cells and macrophages, by activating NF-κB signaling through the virulence factor CagA and thus, induced IL-17A expression in FOXP3+ T cells. Moreover, CD4+ IL-17A+ FOXP3+ T cells were positively associated with advanced precancerous lesions. Therefore, these findings offer essential insights into how FOXP3+ T cells sense inflammatory signals from the environment, such as IL-6, during H. pylori infections, thereby guiding the effector immune response and aggravating the gastritis.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Humanos , Interleucina-17/metabolismo , Interleucina-6 , Gastrite/metabolismo , Gastrite/patologia , Inflamação , Linfócitos T Reguladores , Fatores de Transcrição Forkhead/metabolismo , Microambiente Tumoral
20.
Am J Pathol ; 194(7): 1285-1293, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38588853

RESUMO

Bronchial premalignant lesions (PMLs) precede the development of invasive lung squamous cell carcinoma (LUSC), posing a significant challenge in distinguishing those likely to advance to LUSC from those that might regress without intervention. This study followed a novel computational approach, the Graph Perceiver Network, leveraging hematoxylin and eosin-stained whole slide images to stratify endobronchial biopsies of PMLs across a spectrum from normal to tumor lung tissues. The Graph Perceiver Network outperformed existing frameworks in classification accuracy predicting LUSC, lung adenocarcinoma, and nontumor lung tissue on The Cancer Genome Atlas and Clinical Proteomic Tumor Analysis Consortium datasets containing lung resection tissues while efficiently generating pathologist-aligned, class-specific heatmaps. The network was further tested using endobronchial biopsies from two data cohorts, containing normal to carcinoma in situ histology. It demonstrated a unique capability to differentiate carcinoma in situ lung squamous PMLs based on their progression status to invasive carcinoma. The network may have utility in stratifying PMLs for chemoprevention trials or more aggressive follow-up.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Pulmonares , Lesões Pré-Cancerosas , Humanos , Lesões Pré-Cancerosas/patologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Carcinoma de Células Escamosas/patologia
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