Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.994
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38866017

RESUMEN

Ongoing, early-stage clinical trials illustrate the translational potential of human pluripotent stem cell (hPSC)-based cell therapies in Parkinson's disease (PD). However, an unresolved challenge is the extensive cell death following transplantation. Here, we performed a pooled CRISPR-Cas9 screen to enhance postmitotic dopamine neuron survival in vivo. We identified p53-mediated apoptotic cell death as a major contributor to dopamine neuron loss and uncovered a causal link of tumor necrosis factor alpha (TNF-α)-nuclear factor κB (NF-κB) signaling in limiting cell survival. As a translationally relevant strategy to purify postmitotic dopamine neurons, we identified cell surface markers that enable purification without the need for genetic reporters. Combining cell sorting and treatment with adalimumab, a clinically approved TNF-α inhibitor, enabled efficient engraftment of postmitotic dopamine neurons with extensive reinnervation and functional recovery in a preclinical PD mouse model. Thus, transient TNF-α inhibition presents a clinically relevant strategy to enhance survival and enable engraftment of postmitotic hPSC-derived dopamine neurons in PD.

2.
Cell ; 180(4): 729-748.e26, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-32059776

RESUMEN

We undertook a comprehensive proteogenomic characterization of 95 prospectively collected endometrial carcinomas, comprising 83 endometrioid and 12 serous tumors. This analysis revealed possible new consequences of perturbations to the p53 and Wnt/ß-catenin pathways, identified a potential role for circRNAs in the epithelial-mesenchymal transition, and provided new information about proteomic markers of clinical and genomic tumor subgroups, including relationships to known druggable pathways. An extensive genome-wide acetylation survey yielded insights into regulatory mechanisms linking Wnt signaling and histone acetylation. We also characterized aspects of the tumor immune landscape, including immunogenic alterations, neoantigens, common cancer/testis antigens, and the immune microenvironment, all of which can inform immunotherapy decisions. Collectively, our multi-omic analyses provide a valuable resource for researchers and clinicians, identify new molecular associations of potential mechanistic significance in the development of endometrial cancers, and suggest novel approaches for identifying potential therapeutic targets.


Asunto(s)
Carcinoma/genética , Neoplasias Endometriales/genética , Regulación Neoplásica de la Expresión Génica , Proteoma/genética , Transcriptoma , Acetilación , Animales , Antígenos de Neoplasias/genética , Carcinoma/inmunología , Carcinoma/patología , Neoplasias Endometriales/inmunología , Neoplasias Endometriales/patología , Transición Epitelial-Mesenquimal/genética , Retroalimentación Fisiológica , Femenino , Inestabilidad Genómica , Humanos , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Repeticiones de Microsatélite , Fosforilación , Procesamiento Proteico-Postraduccional , Proteoma/metabolismo , Transducción de Señal
3.
Cell ; 169(1): 132-147.e16, 2017 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-28340339

RESUMEN

The accumulation of irreparable cellular damage restricts healthspan after acute stress or natural aging. Senescent cells are thought to impair tissue function, and their genetic clearance can delay features of aging. Identifying how senescent cells avoid apoptosis allows for the prospective design of anti-senescence compounds to address whether homeostasis can also be restored. Here, we identify FOXO4 as a pivot in senescent cell viability. We designed a FOXO4 peptide that perturbs the FOXO4 interaction with p53. In senescent cells, this selectively causes p53 nuclear exclusion and cell-intrinsic apoptosis. Under conditions where it was well tolerated in vivo, this FOXO4 peptide neutralized doxorubicin-induced chemotoxicity. Moreover, it restored fitness, fur density, and renal function in both fast aging XpdTTD/TTD and naturally aged mice. Thus, therapeutic targeting of senescent cells is feasible under conditions where loss of health has already occurred, and in doing so tissue homeostasis can effectively be restored.


Asunto(s)
Envejecimiento/patología , Antibióticos Antineoplásicos/efectos adversos , Péptidos de Penetración Celular/farmacología , Doxorrubicina/efectos adversos , Envejecimiento/efectos de los fármacos , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacología , Apoptosis , Proteínas de Ciclo Celular , Línea Celular , Supervivencia Celular , Senescencia Celular/efectos de los fármacos , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Femenino , Fibroblastos/citología , Factores de Transcripción Forkhead/química , Factores de Transcripción Forkhead/metabolismo , Humanos , Cuerpos de Inclusión/efectos de los fármacos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Riñón/efectos de los fármacos , Riñón/fisiología , Hígado/efectos de los fármacos , Hígado/fisiología , Masculino , Ratones , Síndromes de Tricotiodistrofia/tratamiento farmacológico , Proteína p53 Supresora de Tumor/metabolismo
4.
Cell ; 169(7): 1327-1341.e23, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28622513

RESUMEN

Liver cancer has the second highest worldwide cancer mortality rate and has limited therapeutic options. We analyzed 363 hepatocellular carcinoma (HCC) cases by whole-exome sequencing and DNA copy number analyses, and we analyzed 196 HCC cases by DNA methylation, RNA, miRNA, and proteomic expression also. DNA sequencing and mutation analysis identified significantly mutated genes, including LZTR1, EEF1A1, SF3B1, and SMARCA4. Significant alterations by mutation or downregulation by hypermethylation in genes likely to result in HCC metabolic reprogramming (ALB, APOB, and CPS1) were observed. Integrative molecular HCC subtyping incorporating unsupervised clustering of five data platforms identified three subtypes, one of which was associated with poorer prognosis in three HCC cohorts. Integrated analyses enabled development of a p53 target gene expression signature correlating with poor survival. Potential therapeutic targets for which inhibitors exist include WNT signaling, MDM4, MET, VEGFA, MCL1, IDH1, TERT, and immune checkpoint proteins CTLA-4, PD-1, and PD-L1.


Asunto(s)
Carcinoma Hepatocelular/genética , Genómica , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/virología , Metilación de ADN , Humanos , Isocitrato Deshidrogenasa/genética , Neoplasias Hepáticas/virología , MicroARNs/genética , Mutación
5.
Genes Dev ; 2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-35981754

RESUMEN

Hepatocyte polyploidization is a tightly controlled process that is initiated at weaning and increases with age. The proliferation of polyploid hepatocytes in vivo is restricted by the PIDDosome-P53 axis, but how this pathway is triggered remains unclear. Given that increased hepatocyte ploidy protects against malignant transformation, the evolutionary driver that sets the upper limit for hepatocyte ploidy remains unknown. Here we show that hepatocytes accumulate centrioles during cycles of polyploidization in vivo. The presence of excess mature centrioles containing ANKRD26 was required to activate the PIDDosome in polyploid cells. As a result, mice lacking centrioles in the liver or ANKRD26 exhibited increased hepatocyte ploidy. Under normal homeostatic conditions, this increase in liver ploidy did not impact organ function. However, in response to chronic liver injury, blocking centriole-mediated ploidy control leads to a massive increase in hepatocyte polyploidization, severe liver damage, and impaired liver function. These results show that hyperpolyploidization sensitizes the liver to injury, posing a trade-off for the cancer-protective effect of increased hepatocyte ploidy. Our results may have important implications for unscheduled polyploidization that frequently occurs in human patients with chronic liver disease.

6.
Genes Dev ; 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902118

RESUMEN

The PBRM1 subunit of the PBAF (SWI/SNF) chromatin remodeling complex is mutated in ∼40% of clear cell renal cancers. PBRM1 loss has been implicated in responses to immunotherapy in renal cancer, but the mechanism is unclear. DNA damage-induced inflammatory signaling is an important factor determining immunotherapy response. This response is kept in check by the G2/M checkpoint, which prevents progression through mitosis with unrepaired damage. We found that in the absence of PBRM1, p53-dependent p21 up-regulation is delayed after DNA damage, leading to defective transcriptional repression by the DREAM complex and premature entry into mitosis. Consequently, DNA damage-induced inflammatory signaling pathways are activated by cytosolic DNA. Notably, p53 is infrequently mutated in renal cancer, so PBRM1 mutational status is critical to G2/M checkpoint maintenance. Moreover, we found that the ability of PBRM1 deficiency to predict response to immunotherapy correlates with expression of the cytosolic DNA-sensing pathway in clinical samples. These findings have implications for therapeutic responses in renal cancer.

7.
EMBO J ; 42(7): e112358, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36762421

RESUMEN

The recognition of polyadenylation signals (PAS) in eukaryotic pre-mRNAs is usually coupled to transcription termination, occurring while pre-mRNA is chromatin-bound. However, for some pre-mRNAs, this 3'-end processing occurs post-transcriptionally, i.e., through a co-transcriptional cleavage (CoTC) event downstream of the PAS, leading to chromatin release and subsequent PAS cleavage in the nucleoplasm. While DNA-damaging agents trigger the shutdown of co-transcriptional chromatin-associated 3'-end processing, specific compensatory mechanisms exist to ensure efficient 3'-end processing for certain pre-mRNAs, including those that encode proteins involved in the DNA damage response, such as the tumor suppressor p53. We show that cleavage at the p53 polyadenylation site occurs in part post-transcriptionally following a co-transcriptional cleavage event. Cells with an engineered deletion of the p53 CoTC site exhibit impaired p53 3'-end processing, decreased mRNA and protein levels of p53 and its transcriptional target p21, and altered cell cycle progression upon UV-induced DNA damage. Using a transcriptome-wide analysis of PAS cleavage, we identify additional pre-mRNAs whose PAS cleavage is maintained in response to UV irradiation and occurring post-transcriptionally. These findings indicate that CoTC-type cleavage of pre-mRNAs, followed by PAS cleavage in the nucleoplasm, allows certain pre-mRNAs to escape 3'-end processing inhibition in response to UV-induced DNA damage.


Asunto(s)
Poliadenilación , Proteína p53 Supresora de Tumor , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Daño del ADN , Precursores del ARN/genética , Precursores del ARN/metabolismo , Cromatina
8.
J Biol Chem ; 300(3): 105707, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309505

RESUMEN

Liver cancer is notoriously refractory to conventional therapeutics. Tumor progression is governed by the interplay between tumor-promoting genes and tumor-suppressor genes. BRD4, an acetyl lysine-binding protein, is overexpressed in many cancer types, which promotes activation of a pro-tumor gene network. But the underlying mechanism for BRD4 overexpression remains incompletely understood. In addition, understanding the regulatory mechanism of BRD4 protein level will shed insight into BRD4-targeting therapeutics. In this study, we investigated the potential relation between BRD4 protein level and P53, the most frequently dysregulated tumor suppressor. By analyzing the TCGA datasets, we first identify a strong negative correlation between protein levels of P53 and BRD4 in liver cancer. Further investigation shows that P53 promotes BRD4 protein degradation. Mechanistically, P53 indirectly represses the transcription of USP1, a deubiquitinase, through the P21-RB1 axis. USP1 itself is also overexpressed in liver cancer and we show USP1 deubiquitinates BRD4 in vivo and in vitro, which increases BRD4 stability. With cell proliferation assays and xenograft model, we show the pro-tumor role of USP1 is partially mediated by BRD4. With functional transcriptomic analysis, we find the USP1-BRD4 axis upholds expression of a group of cancer-related genes. In summary, we identify a functional P53-P21-RB1-USP1-BRD4 axis in liver cancer.


Asunto(s)
Proteínas que Contienen Bromodominio , Proteínas de Ciclo Celular , Neoplasias Hepáticas , Proteínas Nucleares , Factores de Transcripción , Proteasas Ubiquitina-Específicas , Humanos , Proteínas que Contienen Bromodominio/genética , Proteínas que Contienen Bromodominio/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Genes Supresores de Tumor , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Unión a Retinoblastoma/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo
9.
Annu Rev Genomics Hum Genet ; 23: 331-361, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-36044908

RESUMEN

A mosaic state arises when pathogenic variants are acquired in certain cell lineages during postzygotic development, and mosaic individuals may present with a generalized or localized phenotype. Here, we review the current state of knowledge regarding mosaicism for eight common tumor suppressor genes-NF1, NF2, TSC1, TSC2, PTEN, VHL, RB1, and TP53-and their related genetic syndromes/entities. We compare and discuss approaches for comprehensive diagnostic genetic testing, the spectrum of variant allele frequency, and disease severity. We also review affected individuals who have no mutation identified after conventional genetic analysis, as well as genotype-phenotype correlations and transmission risk for each tumor suppressor gene in full heterozygous and mosaic patients. This review provides new insight into similarities as well as marked differences regarding the appreciation of mosaicism in these tumor suppressor syndromes.


Asunto(s)
Genes Supresores de Tumor , Mosaicismo , Humanos , Mutación , Fenotipo , Prevalencia
10.
EMBO J ; 40(1): e106118, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33226141

RESUMEN

Mutations in centrosome genes deplete neural progenitor cells (NPCs) during brain development, causing microcephaly. While NPC attrition is linked to TP53-mediated cell death in several microcephaly models, how TP53 is activated remains unclear. In cultured cells, mitotic delays resulting from centrosome loss prevent the growth of unfit daughter cells by activating a pathway involving 53BP1, USP28, and TP53, termed the mitotic surveillance pathway. Whether this pathway is active in the developing brain is unknown. Here, we show that the depletion of centrosome proteins in NPCs prolongs mitosis and increases TP53-mediated apoptosis. Cell death after a delayed mitosis was rescued by inactivation of the mitotic surveillance pathway. Moreover, 53BP1 or USP28 deletion restored NPC proliferation and brain size without correcting the upstream centrosome defects or extended mitosis. By contrast, microcephaly caused by the loss of the non-centrosomal protein SMC5 is also TP53-dependent but is not rescued by loss of 53BP1 or USP28. Thus, we propose that mutations in centrosome genes cause microcephaly by delaying mitosis and pathologically activating the mitotic surveillance pathway in the developing brain.


Asunto(s)
Centrosoma/metabolismo , Microcefalia/genética , Microcefalia/metabolismo , Mitosis/genética , Proteína p53 Supresora de Tumor/genética , Proteína 1 de Unión al Supresor Tumoral P53/genética , Ubiquitina Tiolesterasa/genética , Animales , Apoptosis/genética , Encéfalo/patología , Muerte Celular/genética , Proliferación Celular/genética , Células Cultivadas , Ratones , Ratones Noqueados , Mutación/genética , Transducción de Señal/genética
11.
Am J Hum Genet ; 109(10): 1777-1788, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36206742

RESUMEN

Rare pathogenic variants in known breast cancer-susceptibility genes and known common susceptibility variants do not fully explain the familial aggregation of breast cancer. To investigate plausible genetic models for the residual familial aggregation, we studied 17,425 families ascertained through population-based probands, 86% of whom were screened for pathogenic variants in BRCA1, BRCA2, PALB2, CHEK2, ATM, and TP53 via gene-panel sequencing. We conducted complex segregation analyses and fitted genetic models in which breast cancer incidence depended on the effects of known susceptibility genes and other unidentified major genes and a normally distributed polygenic component. The proportion of familial variance explained by the six genes was 46% at age 20-29 years and decreased steadily with age thereafter. After allowing for these genes, the best fitting model for the residual familial variance included a recessive risk component with a combined genotype frequency of 1.7% (95% CI: 0.3%-5.4%) and a penetrance to age 80 years of 69% (95% CI: 38%-95%) for homozygotes, which may reflect the combined effects of multiple variants acting in a recessive manner, and a polygenic variance of 1.27 (95% CI: 0.94%-1.65), which did not vary with age. The proportion of the residual familial variance explained by the recessive risk component was 40% at age 20-29 years and decreased with age thereafter. The model predicted age-specific familial relative risks consistent with those observed by large epidemiological studies. The findings have implications for strategies to identify new breast cancer-susceptibility genes and improve disease-risk prediction, especially at a young age.


Asunto(s)
Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Adulto , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Femenino , Humanos , Herencia Multifactorial/genética , Penetrancia , Adulto Joven
12.
J Pathol ; 262(2): 147-160, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38010733

RESUMEN

TP53 is the most frequently mutated gene in human cancer. This gene shows not only loss-of-function mutations but also recurrent missense mutations with gain-of-function activity. We have studied the primary bone malignancy osteosarcoma, which harbours one of the most rearranged genomes of all cancers. This is odd since it primarily affects children and adolescents who have not lived the long life thought necessary to accumulate massive numbers of mutations. In osteosarcoma, TP53 is often disrupted by structural variants. Here, we show through combined whole-genome and transcriptome analyses of 148 osteosarcomas that TP53 structural variants commonly result in loss of coding parts of the gene while simultaneously preserving and relocating the promoter region. The transferred TP53 promoter region is fused to genes previously implicated in cancer development. Paradoxically, these erroneously upregulated genes are significantly associated with the TP53 signalling pathway itself. This suggests that while the classical tumour suppressor activities of TP53 are lost, certain parts of the TP53 signalling pathway that are necessary for cancer cell survival and proliferation are retained. In line with this, our data suggest that transposition of the TP53 promoter is an early event that allows for a new normal state of genome-wide rearrangements in osteosarcoma. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Niño , Adolescente , Humanos , Genes p53 , Osteosarcoma/genética , Osteosarcoma/patología , Mutación , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Regiones Promotoras Genéticas/genética , Fusión Génica , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
13.
J Pathol ; 263(2): 131-134, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38482738

RESUMEN

Gene disruption from double-strand DNA breaks within introns is a mechanism of inactivating the tumor suppressor TP53. This occurs more frequently in osteosarcoma and biliary adenocarcinoma compared with other cancer types. The patterns of intron breakpoints within TP53 do not correlate with prevalence, intron length, or overall genome-wide levels of rearrangements. Therefore, these breakpoints appear to be selected for reasons other than to disrupt TP53. A recent article published by Saba et al in The Journal of Pathology illustrates a benefit to having breakpoints within intron 1 using high-quality matched genomic and transcriptomic osteosarcoma sequencing data as well as in vitro validation. The authors describe how the rearrangement results in relocation of the TP53 promoter region to regions upstream of genes that encode members of cartilage, growth plate development, osteoclast formation, and other TP53-related pathways. The upregulation of these genes by the TP53 promoter are gain-of-function events that are likely to promote tumor development and growth. Therefore, this article presents a potential new paradigm in which a single mutation would result in both the loss of a tumor suppressor and the gain of an oncogenic program. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Intrones , Regiones Promotoras Genéticas , Proteína p53 Supresora de Tumor , Humanos , Regiones Promotoras Genéticas/genética , Proteína p53 Supresora de Tumor/genética , Intrones/genética , Osteosarcoma/genética , Osteosarcoma/patología , Mutación
14.
J Pathol ; 263(2): 139-149, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38380548

RESUMEN

TP53 mutation is one of the most common genetic alterations in urothelial carcinoma (UrCa), and heterogeneity of TP53 mutants leads to heterogeneous clinical outcomes. This study aimed to investigate the clinical relevance of specific TP53 mutations in UrCa. In this study, a total of eight cohorts were enrolled, along with matched clinical annotation. TP53 mutations were classified as disruptive and nondisruptive according to the degree of disturbance of p53 protein function and structure. We evaluated the clinical significance of TP53 mutations in our local datasets and publicly available datasets. The co-occurring events of TP53 mutations in UrCa, along with their therapeutic indications, functional effects, and the tumor immune microenvironment, were also investigated. TP53 mutations were identified in 49.7% of the UrCa patients. Within this group, 25.1% of patients carried TP53Disruptive mutations, a genetic alteration correlated with a significantly poorer overall survival (OS) when compared to individuals with TP53Nondisruptive mutations and those with wild-type TP53. Significantly, patients with TP53Disruptive mutations exhibit an increased probability of responding favorably to PD-1/PD-L1 blockade and chemoimmunotherapy. Meanwhile, there was no noteworthy distinction in OS among patients with varying TP53 mutation status who underwent chemotherapy. Samples with TP53Disruptive mutations showed an enriched APOBEC- and POLE-related mutational signature, as well as an elevated tumor mutation burden. The sensitivity to immunotherapy in tumors carrying TP53Disruptive mutation may be attributed to the inflamed tumor microenvironment characterized by increased CD8+T cell infiltration and interferon-gamma signaling activation. In conclusion, UrCa patients with TP53Disruptive mutations have shown reduced survival rates, yet they may respond well to PD-1/PD-L1 blockade therapy and chemoimmunotherapy. By distinguishing specific TP53 mutations, we can improve risk stratification and offer personalized genomics-guided therapy to UrCa patients. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Antígeno B7-H1 , Inhibidores de Puntos de Control Inmunológico , Mutación , Receptor de Muerte Celular Programada 1 , Microambiente Tumoral , Proteína p53 Supresora de Tumor , Neoplasias de la Vejiga Urinaria , Humanos , Proteína p53 Supresora de Tumor/genética , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/genética , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/genética , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/inmunología , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/genética , Carcinoma de Células Transicionales/inmunología , Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/mortalidad , Biomarcadores de Tumor/genética , Masculino , Femenino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anciano , Persona de Mediana Edad
15.
J Pathol ; 263(3): 386-395, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38801208

RESUMEN

While increased DNA damage is a well-described feature of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), it is unclear whether all lineages and all regions of the marrow are homogeneously affected. In this study, we performed immunohistochemistry on formalin-fixed, paraffin-embedded whole-section bone marrow biopsies using a well-established antibody to detect pH2A.X (phosphorylated histone variant H2A.X) that recognizes DNA double-strand breaks. Focusing on TP53-mutated and complex karyotype MDS/AML, we find a greater pH2A.X+ DNA damage burden compared to TP53 wild-type neoplastic cases and non-neoplastic controls. To understand how double-strand breaks vary between lineages and spatially in TP53-mutated specimens, we applied a low-multiplex immunofluorescence staining and spatial analysis protocol to visualize pH2A.X+ cells with p53 protein staining and lineage markers. pH2A.X marked predominantly mid- to late-stage erythroids, whereas early erythroids and CD34+ blasts were relatively spared. In a prototypical example, these pH2A.X+ erythroids were organized locally as distinct colonies, and each colony displayed pH2A.X+ puncta at a synchronous level. This highly coordinated immunophenotypic expression was also seen for p53 protein staining and among presumed early myeloid colonies. Neighborhood clustering analysis showed distinct marrow regions differentially enriched in pH2A.X+/p53+ erythroid or myeloid colonies, indicating spatial heterogeneity of DNA-damage response and p53 protein expression. The lineage and architectural context within which DNA damage phenotype and oncogenic protein are expressed is relevant to current therapeutic developments that leverage macrophage phagocytosis to remove leukemic cells in part due to irreparable DNA damage. © 2024 The Pathological Society of Great Britain and Ireland.


Asunto(s)
Mutación , Síndromes Mielodisplásicos , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/metabolismo , Persona de Mediana Edad , Daño del ADN , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/metabolismo , Anciano , Femenino , Roturas del ADN de Doble Cadena , Histonas/metabolismo , Histonas/genética , Médula Ósea/patología , Médula Ósea/metabolismo , Anciano de 80 o más Años , Inmunohistoquímica
16.
Proc Natl Acad Sci U S A ; 119(14): e2120403119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35357972

RESUMEN

Inactivation of the VHL tumor suppressor gene is the signature initiating event in clear cell renal cell carcinoma (ccRCC), which is the most common form of kidney cancer. The VHL tumor suppressor protein marks hypoxia-inducible factor 1 (HIF1) and HIF2 for proteasomal degradation when oxygen is present. The inappropriate accumulation of HIF2 drives tumor formation by VHL tumor suppressor protein (pVHL)­defective ccRCC. Belzutifan, a first-in-class allosteric HIF2 inhibitor, has advanced to phase 3 testing for advanced ccRCC and is approved for ccRCCs arising in patients with VHL disease, which is caused by germline VHL mutations. HIF2 can suppress p53 function in some settings and preliminary data suggested that an intact p53 pathway, as measured by activation in response to DNA damage, was necessary for HIF2 dependence. Here, we correlated HIF2 dependence and p53 status across a broader collection of ccRCC cell lines. We also genetically manipulated p53 function in ccRCC lines that were or were not previously HIF2-dependent and then assessed their subsequent sensitivity to HIF2 ablation using CRISPR-Cas9 or the HIF2 inhibitor PT2399, which is closely related to belzutifan. From these studies, we conclude that p53 status does not dictate HIF2 dependence, at least in preclinical models, and thus is unlikely to be a useful biomarker for predicting which ccRCC patients will respond to HIF2 inhibitors.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Carcinoma de Células Renales , Indanos , Neoplasias Renales , Sulfonas , Proteína p53 Supresora de Tumor , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Indanos/farmacología , Indanos/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/genética , Neoplasias Renales/patología , Masculino , Sulfonas/farmacología , Sulfonas/uso terapéutico , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo
17.
Proc Natl Acad Sci U S A ; 119(27): e2123227119, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35759659

RESUMEN

DNA methyltransferase inhibitors (DNMTis) reexpress hypermethylated genes in cancers and leukemias and also activate endogenous retroviruses (ERVs), leading to interferon (IFN) signaling, in a process known as viral mimicry. In the present study we show that in the subset of acute myeloid leukemias (AMLs) with mutations in TP53, associated with poor prognosis, DNMTis, important drugs for treatment of AML, enable expression of ERVs and IFN and inflammasome signaling in a STING-dependent manner. We previously reported that in solid tumors poly ADP ribose polymerase inhibitors (PARPis) combined with DNMTis to induce an IFN/inflammasome response that is dependent on STING1 and is mechanistically linked to generation of a homologous recombination defect (HRD). We now show that STING1 activity is actually increased in TP53 mutant compared with wild-type (WT) TP53 AML. Moreover, in TP53 mutant AML, STING1-dependent IFN/inflammatory signaling is increased by DNMTi treatment, whereas in AMLs with WT TP53, DNMTis alone have no effect. While combining DNMTis with PARPis increases IFN/inflammatory gene expression in WT TP53 AML cells, signaling induced in TP53 mutant AML is still several-fold higher. Notably, induction of HRD in both TP53 mutant and WT AMLs follows the pattern of STING1-dependent IFN and inflammatory signaling that we have observed with drug treatments. These findings increase our understanding of the mechanisms that underlie DNMTi + PARPi treatment, and also DNMTi combinations with immune therapies, suggesting a personalized approach that statifies by TP53 status, for use of such therapies, including potential immune activation of STING1 in AML and other cancers.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , ADN-Citosina Metilasas , Leucemia Mieloide Aguda , Proteínas de la Membrana , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Proteína p53 Supresora de Tumor , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , ADN-Citosina Metilasas/antagonistas & inhibidores , Recombinación Homóloga/genética , Humanos , Inflamasomas/metabolismo , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/inmunología , Proteínas de la Membrana/inmunología , Mutación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Transducción de Señal , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
18.
Carcinogenesis ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38868979

RESUMEN

BRAF V600E, one of the most frequent mutations in the MAPK pathway, confers poor prognosis to colorectal cancers (CRCs), partly because of chemotherapeutic resistance. Oncogene-induced DNA damage responses (DDRs) that primarily activate p53 are important mechanistic barriers to the malignant transformation of cells; however, the mechanism underlying this impairment in cancer remains unknown. Here, we evaluated the responses of BRAFV600E-induced DDRs in two CRC cell lines, SW48 and LIM1215, both of which harbor wild-type TP53, KRAS, and BRAF. BRAFV600E transduction exhibited distinct phenotypes in these cells: SW48 cell proliferation markedly decreased, whereas that of LIM1215 increased. BRAFV600E expression induced the activation of oncogene-induced DDR signaling in SW48 cells, but not in LIM1215 cells, whereas chemotherapeutic agents similarly activated DDRs in both cell lines. Knockdown experiments revealed that these responses in SW48 cells were mediated by p53-p21 pathway activation. Comet assay (both alkaline and neutral) revealed that BRAFV600E increased single-strand breaks to the same extent in both cell lines; however, in case of LIM1215 cells, it only facilitated double-strand breaks. Furthermore, the proliferation of LIM1215 cells, wherein no oncogene-induced DDRs occurred, was synergistically inhibited upon MDM2 inhibitor-mediated p53 activation combined with MEK inhibition. Taken together, these distinct DDR signaling responses highlight the novel characteristics of BRAFV600E-mutated CRC cells and define the therapeutic potential of p53 activation combined with MAPK inhibition against TP53 wild-type CRC harboring a BRAFV600E mutation.

19.
J Cell Mol Med ; 28(10): e18378, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38760895

RESUMEN

The efficacy of radiotherapy, a cornerstone in the treatment of lung adenocarcinoma (LUAD), is profoundly undermined by radiotolerance. This resistance not only poses a significant clinical challenge but also compromises patient survival rates. Therefore, it is important to explore this mechanism for the treatment of LUAD. Multiple public databases were used for single-cell RNA sequencing (scRNA-seq) data. We filtered, normalized and downscaled scRNA-seq data based on the Seurat package to obtain different cell subpopulations. Subsequently, the ssGSEA algorithm was used to assess the enrichment scores of the different cell subpopulations, and thus screen the cell subpopulations that are most relevant to radiotherapy tolerance based on the Pearson method. Finally, pseudotime analysis was performed, and a preliminary exploration of gene mutations in different cell subpopulations was performed. We identified HIST1H1D+ A549 and PIF1+ A549 as the cell subpopulations related to radiotolerance. The expression levels of cell cycle-related genes and pathway enrichment scores of these two cell subpopulations increased gradually with the extension of radiation treatment time. Finally, we found that the proportion of TP53 mutations in patients who had received radiotherapy was significantly higher than that in patients who had not received radiotherapy. We identified two cellular subpopulations associated with radiotherapy tolerance, which may shed light on the molecular mechanisms of radiotherapy tolerance in LUAD and provide new clinical perspectives.


Asunto(s)
Adenocarcinoma del Pulmón , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , Mutación , Tolerancia a Radiación , Análisis de la Célula Individual , Humanos , Análisis de la Célula Individual/métodos , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/radioterapia , Adenocarcinoma del Pulmón/patología , Tolerancia a Radiación/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patología , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Análisis de Secuencia de ARN/métodos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Células A549 , Perfilación de la Expresión Génica , Línea Celular Tumoral
20.
Mol Cancer ; 23(1): 127, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38880903

RESUMEN

The clinical heterogeneity of early-stage endometrial cancer (EC) is worthy of further study to identify high-quality prognostic markers and their potential role in aggressive tumor behavior. Mutation of TP53 was considered as an important primary triage in modified molecular typing for EC, it still cannot precisely predict the prognosis of EC. After proteomic analysis of cancer and para-cancerous tissues from 24 early-stage endometrioid EC patients with different survival outcomes, 13 differentially expressed proteins were screen out while 2 proteins enriched in p53 signaling pathway were further identified by single-cell transcriptome (scRNA-seq). Interestingly, tumor necrosis factor type-1 receptor-associated protein (TRAP1) and calmodulin-regulated spectrin-associated protein family member 3 (CAMSAP3) were found to be significantly downregulated in the specific cell cluster. Expectedly, the signature genes of TRAP1low/CAMSAP3low cluster included classical oncogenes. Moreover, close cellular interactions were observed between myeloid cells and the TRAP1low/CAMSAP3low cluster after systematically elucidating their relationship with tumor microenvironment (TME). The expression of TRAP1 and CAMSAP3 was verified by immunohistochemistry. Thus, a novel prediction model combining TRAP1, CAMSAP3 and TP53 was construct by multi-omics. Compared with the area under the curve, it demonstrated a significantly improvemrnt in the diagnostic efficacy in EC patients from TCGA bank. In conclusion, this work improved the current knowledge regarding the prognosis of early-stage EC through proteomics and scRNA-seq. These findings may lead to improvements in precise risk stratification of early-stage EC patients.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Endometriales , Regulación Neoplásica de la Expresión Génica , Estadificación de Neoplasias , Proteómica , Humanos , Femenino , Neoplasias Endometriales/genética , Neoplasias Endometriales/patología , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/mortalidad , Pronóstico , Biomarcadores de Tumor/genética , Proteómica/métodos , Microambiente Tumoral/genética , Perfilación de la Expresión Génica , Persona de Mediana Edad , Transcriptoma , Multiómica , Proteínas HSP90 de Choque Térmico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA