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1.
Cancer Res ; 83(24): 4015-4029, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37987734

RESUMO

MYC is a central regulator of gene transcription and is frequently dysregulated in human cancers. As targeting MYC directly is challenging, an alternative strategy is to identify specific proteins or processes required for MYC to function as a potent cancer driver that can be targeted to result in synthetic lethality. To identify potential targets in MYC-driven cancers, we performed a genome-wide CRISPR knockout screen using an isogenic pair of breast cancer cell lines in which MYC dysregulation is the switch from benign to transformed tumor growth. Proteins that regulate R-loops were identified as a potential class of synthetic lethal targets. Dysregulated MYC elevated global transcription and coincident R-loop accumulation. Topoisomerase 1 (TOP1), a regulator of R-loops by DNA topology, was validated to be a vulnerability in cells with high MYC activity. Genetic knockdown of TOP1 in MYC-transformed cells resulted in reduced colony formation compared with control cells, demonstrating synthetic lethality. Overexpression of RNaseH1, a riboendonuclease that specifically degrades R-loops, rescued the reduction in clonogenicity induced by TOP1 deficiency, demonstrating that this vulnerability is driven by aberrant R-loop accumulation. Genetic and pharmacologic TOP1 inhibition selectively reduced the fitness of MYC-transformed tumors in vivo. Finally, drug response to TOP1 inhibitors (i.e., topotecan) significantly correlated with MYC levels and activity across panels of breast cancer cell lines and patient-derived organoids. Together, these results highlight TOP1 as a promising target for MYC-driven cancers. SIGNIFICANCE: CRISPR screening reveals topoisomerase 1 as an immediately actionable vulnerability in cancers harboring MYC as a driver oncoprotein that can be targeted with clinically approved inhibitors.


Assuntos
Neoplasias da Mama , Estruturas R-Loop , Humanos , Feminino , Mutações Sintéticas Letais , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Inibidores da Topoisomerase I/farmacologia , Linhagem Celular Tumoral
2.
Cell Rep ; 42(10): 113256, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37847590

RESUMO

It is widely assumed that all normal somatic cells can equally perform homologous recombination (HR) and non-homologous end joining in the DNA damage response (DDR). Here, we show that the DDR in normal mammary gland inherently depends on the epithelial cell lineage identity. Bioinformatics, post-irradiation DNA damage repair kinetics, and clonogenic assays demonstrated luminal lineage exhibiting a more pronounced DDR and HR repair compared to the basal lineage. Consequently, basal progenitors were far more sensitive to poly(ADP-ribose) polymerase inhibitors (PARPis) in both mouse and human mammary epithelium. Furthermore, PARPi sensitivity of murine and human breast cancer cell lines as well as patient-derived xenografts correlated with their molecular resemblance to the mammary progenitor lineages. Thus, mammary epithelial cells are intrinsically divergent in their DNA damage repair capacity and PARPi vulnerability, potentially influencing the clinical utility of this targeted therapy.


Assuntos
Antineoplásicos , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Animais , Camundongos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Antineoplásicos/farmacologia , Reparo do DNA , Recombinação Homóloga , Dano ao DNA
4.
Nat Commun ; 13(1): 1895, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393420

RESUMO

Breast cancer risk for carriers of BRCA1 pathological variants is modified by genetic factors. Genetic variation in HMMR may contribute to this effect. However, the impact of risk modifiers on cancer biology remains undetermined and the biological basis of increased risk is poorly understood. Here, we depict an interplay of molecular, cellular, and tissue microenvironment alterations that increase BRCA1-associated breast cancer risk. Analysis of genome-wide association results suggests that diverse biological processes, including links to BRCA1-HMMR profiles, influence risk. HMMR overexpression in mouse mammary epithelium increases Brca1-mutant tumorigenesis by modulating the cancer cell phenotype and tumor microenvironment. Elevated HMMR activates AURKA and reduces ARPC2 localization in the mitotic cell cortex, which is correlated with micronucleation and activation of cGAS-STING and non-canonical NF-κB signaling. The initial tumorigenic events are genomic instability, epithelial-to-mesenchymal transition, and tissue infiltration of tumor-associated macrophages. The findings reveal a biological foundation for increased risk of BRCA1-associated breast cancer.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Proteínas da Matriz Extracelular , Receptores de Hialuronatos , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Animais , Proteína BRCA1/genética , Neoplasias da Mama/patologia , Carcinogênese/genética , Proteínas da Matriz Extracelular/genética , Feminino , Estudo de Associação Genômica Ampla , Heterozigoto , Humanos , Receptores de Hialuronatos/genética , Camundongos , Microambiente Tumoral/genética
5.
Hum Mutat ; 42(11): 1488-1502, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34420246

RESUMO

Germline pathogenic variants in BRCA1 confer a high risk of developing breast and ovarian cancer. The BRCA1 exon 11 (formally exon 10) is one of the largest exons and codes for the nuclear localization signals of the corresponding gene product. This exon can be partially or entirely skipped during pre-mRNA splicing, leading to three major in-frame isoforms that are detectable in most cell types and tissue, and in normal and cancer settings. However, it is unclear whether the splicing imbalance of this exon is associated with cancer risk. Here we identify a common genetic variant in intron 10, rs5820483 (NC_000017.11:g.43095106_43095108dup), which is associated with exon 11 isoform expression and alternative splicing, and with the risk of breast cancer, but not ovarian cancer, in BRCA1 pathogenic variant carriers. The identification of this genetic effect was confirmed by analogous observations in mouse cells and tissue in which a loxP sequence was inserted in the syntenic intronic region. The prediction that the rs5820483 minor allele variant would create a binding site for the splicing silencer hnRNP A1 was confirmed by pull-down assays. Our data suggest that perturbation of BRCA1 exon 11 splicing modifies the breast cancer risk conferred by pathogenic variants of this gene.


Assuntos
Neoplasias da Mama/genética , Éxons , Genes BRCA1 , Triagem de Portadores Genéticos , Predisposição Genética para Doença , Splicing de RNA , Feminino , Humanos , Íntrons
6.
EMBO Mol Med ; 13(9): e13929, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34378323

RESUMO

Inhibition of mTOR is the standard of care for lymphangioleiomyomatosis (LAM). However, this therapy has variable tolerability and some patients show progressive decline of lung function despite treatment. LAM diagnosis and monitoring can also be challenging due to the heterogeneity of symptoms and insufficiency of non-invasive tests. Here, we propose monoamine-derived biomarkers that provide preclinical evidence for novel therapeutic approaches. The major histamine-derived metabolite methylimidazoleacetic acid (MIAA) is relatively more abundant in LAM plasma, and MIAA values are independent of VEGF-D. Higher levels of histamine are associated with poorer lung function and greater disease burden. Molecular and cellular analyses, and metabolic profiling confirmed active histamine signaling and metabolism. LAM tumorigenesis is reduced using approved drugs targeting monoamine oxidases A/B (clorgyline and rasagiline) or histamine H1 receptor (loratadine), and loratadine synergizes with rapamycin. Depletion of Maoa or Hrh1 expression, and administration of an L-histidine analog, or a low L-histidine diet, also reduce LAM tumorigenesis. These findings extend our knowledge of LAM biology and suggest possible ways of improving disease management.


Assuntos
Neoplasias Pulmonares , Linfangioleiomiomatose , Biomarcadores , Histamina , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Linfangioleiomiomatose/tratamento farmacológico , Transdução de Sinais
8.
Nat Metab ; 3(5): 665-681, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34031589

RESUMO

Cancer metabolism adapts the metabolic network of its tissue of origin. However, breast cancer is not a disease of a single origin. Multiple epithelial populations serve as the culprit cell of origin for specific breast cancer subtypes, yet our knowledge of the metabolic network of normal mammary epithelial cells is limited. Using a multi-omic approach, here we identify the diverse metabolic programmes operating in normal mammary populations. The proteomes of basal, luminal progenitor and mature luminal cell populations revealed enrichment of glycolysis in basal cells and of oxidative phosphorylation in luminal progenitors. Single-cell transcriptomes corroborated lineage-specific metabolic identities and additional intra-lineage heterogeneity. Mitochondrial form and function differed across lineages, with clonogenicity correlating with mitochondrial activity. Targeting oxidative phosphorylation and glycolysis with inhibitors exposed lineage-rooted metabolic vulnerabilities of mammary progenitors. Bioinformatics indicated breast cancer subtypes retain metabolic features of their putative cell of origin. Thus, lineage-rooted metabolic identities of normal mammary cells may underlie breast cancer metabolic heterogeneity and targeting these vulnerabilities could advance breast cancer therapy.


Assuntos
Linhagem da Célula , Metabolismo Energético , Células Epiteliais/metabolismo , Glândulas Mamárias Humanas/metabolismo , Animais , Biomarcadores , Biologia Computacional/métodos , Feminino , Citometria de Fluxo/métodos , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Humanas/citologia , Redes e Vias Metabólicas , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteoma , Proteômica/métodos
9.
Sci Transl Med ; 13(580)2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568520

RESUMO

Among the pleotropic roles of transforming growth factor-ß (TGFß) signaling in cancer, its impact on genomic stability is least understood. Inhibition of TGFß signaling increases use of alternative end joining (alt-EJ), an error-prone DNA repair process that typically functions as a "backup" pathway if double-strand break repair by homologous recombination or nonhomologous end joining is compromised. However, the consequences of this functional relationship on therapeutic vulnerability in human cancer remain unknown. Here, we show that TGFß broadly controls the DNA damage response and suppresses alt-EJ genes that are associated with genomic instability. Mechanistically based TGFß and alt-EJ gene expression signatures were anticorrelated in glioblastoma, squamous cell lung cancer, and serous ovarian cancer. Consistent with error-prone repair, more of the genome was altered in tumors classified as low TGFß and high alt-EJ, and the corresponding patients had better outcomes. Pan-cancer analysis of solid neoplasms revealed that alt-EJ genes were coordinately expressed and anticorrelated with TGFß competency in 16 of 17 cancer types tested. Moreover, regardless of cancer type, tumors classified as low TGFß and high alt-EJ were characterized by an insertion-deletion mutation signature containing short microhomologies and were more sensitive to genotoxic therapy. Collectively, experimental studies revealed that loss or inhibition of TGFß signaling compromises the DNA damage response, resulting in ineffective repair by alt-EJ. Translation of this mechanistic relationship into gene expression signatures identified a robust anticorrelation that predicts response to genotoxic therapies, thereby expanding the potential therapeutic scope of TGFß biology.


Assuntos
Reparo do DNA por Junção de Extremidades , Neoplasias , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Reparo do DNA/genética , Humanos , Neoplasias/genética , Fator de Crescimento Transformador beta
10.
J Clin Invest ; 131(3)2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33529165

RESUMO

Germline mutations in BRCA1 and BRCA2 (BRCA1/2) genes considerably increase breast and ovarian cancer risk. Given that tumors with these mutations have elevated genomic instability, they exhibit relative vulnerability to certain chemotherapies and targeted treatments based on poly (ADP-ribose) polymerase (PARP) inhibition. However, the molecular mechanisms that influence cancer risk and therapeutic benefit or resistance remain only partially understood. BRCA1 and BRCA2 have also been implicated in the suppression of R-loops, triple-stranded nucleic acid structures composed of a DNA:RNA hybrid and a displaced ssDNA strand. Here, we report that loss of RNF168, an E3 ubiquitin ligase and DNA double-strand break (DSB) responder, remarkably protected Brca1-mutant mice against mammary tumorigenesis. We demonstrate that RNF168 deficiency resulted in accumulation of R-loops in BRCA1/2-mutant breast and ovarian cancer cells, leading to DSBs, senescence, and subsequent cell death. Using interactome assays, we identified RNF168 interaction with DHX9, a helicase involved in the resolution and removal of R-loops. Mechanistically, RNF168 directly ubiquitylated DHX9 to facilitate its recruitment to R-loop-prone genomic loci. Consequently, loss of RNF168 impaired DHX9 recruitment to R-loops, thereby abrogating its ability to resolve R-loops. The data presented in this study highlight a dependence of BRCA1/2-defective tumors on factors that suppress R-loops and reveal a fundamental RNF168-mediated molecular mechanism that governs cancer development and vulnerability.


Assuntos
Proteína BRCA1/deficiência , Proteína BRCA2/deficiência , DNA de Neoplasias/metabolismo , Instabilidade Genômica , Neoplasias Mamárias Animais/metabolismo , Neoplasias Ovarianas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , DNA de Neoplasias/genética , Feminino , Loci Gênicos , Humanos , Neoplasias Mamárias Animais/genética , Camundongos , Camundongos Knockout , Neoplasias Ovarianas/genética , Ubiquitina-Proteína Ligases/genética
11.
Clin Cancer Res ; 27(5): 1491-1504, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262138

RESUMO

PURPOSE: Recurrent and/or metastatic unresectable cutaneous squamous cell carcinomas (cSCCs) are treated with chemotherapy or radiotherapy, but have poor clinical responses. A limited response (up to 45% of cases) to EGFR-targeted therapies was observed in clinical trials with patients with advanced and metastatic cSCC. Here, we analyze the molecular traits underlying the response to EGFR inhibitors, and the mechanisms responsible for cSCC resistance to EGFR-targeted therapy. EXPERIMENTAL DESIGN: We generated primary cell cultures and patient cSCC-derived xenografts (cSCC-PDXs) that recapitulate the histopathologic and molecular features of patient tumors. Response to gefitinib treatment was tested and gefitinib-resistant (GefR) cSCC-PDXs were developed. RNA sequence analysis was performed in matched untreated and GefR cSCC-PDXs to determine the mechanisms driving gefitinib resistance. RESULTS: cSCCs conserving epithelial traits exhibited strong activation of EGFR signaling, which promoted tumor cell proliferation, in contrast to mesenchymal-like cSCCs. Gefitinib treatment strongly blocked epithelial-like cSCC-PDX growth in the absence of EGFR and RAS mutations, whereas tumors carrying the E545K PIK3CA-activating mutation were resistant to treatment. A subset of initially responding tumors acquired resistance after long-term treatment, which was induced by the bypass from EGFR to FGFR signaling to allow tumor cell proliferation and survival upon gefitinib treatment. Pharmacologic inhibition of FGFR signaling overcame resistance to EGFR inhibitor, even in PIK3CA-mutated tumors. CONCLUSIONS: EGFR-targeted therapy may be appropriate for treating many epithelial-like cSCCs without PIK3CA-activating mutations. Combined EGFR- and FGFR-targeted therapy may be used to treat cSCCs that show intrinsic or acquired resistance to EGFR inhibitors.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Gefitinibe/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Animais , Apoptose , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Inibidores de Proteínas Quinases/farmacologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Eur Urol ; 79(6): 722-733, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33153817

RESUMO

BACKGROUND: Taxanes are the most active chemotherapy agents in metastatic castration-resistant prostate cancer (mCRPC) patients; yet, resistance occurs almost invariably, representing an important clinical challenge. Taxane-platinum combinations have shown clinical benefit in a subset of patients, but the mechanistic basis and biomarkers remain elusive. OBJECTIVE: To identify mechanisms and response indicators for the antitumor efficacy of taxane-platinum combinations in mCRPC. DESIGN, SETTING, AND PARTICIPANTS: Transcriptomic data from a publicly available mCRPC dataset of taxane-exposed and taxane-naïve patients were analyzed to identify response indicators and emerging vulnerabilities. Functional and preclinical validation was performed in taxane-resistant mCRPC cell lines and genetically engineered mouse models (GEMMs). INTERVENTION: Metastatic CRPC cells were treated with docetaxel, cisplatin, carboplatin, the CXCR2 antagonist SB265610, and the BCL-2 inhibitor venetoclax. Gain and loss of function in culture of CXCR2 and BCL-2 were achieved by overexpression or siRNA silencing. Preclinical assays in GEMM mice tested the antitumor efficacy of taxane-platinum combinations. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Proliferation, apoptosis, and colony assays measured drug activity in vitro. Preclinical endpoints in mice included growth, survival, and histopathology. Changes in CXCR2, BCL-2, and chemokines were analyzed by reverse transcriptase quantitative polymerase chain reaction and Western blot. Human expression data were analyzed using Gene Set Enrichment Analysis, hierarchical clustering, and correlation studies. GraphPad Prism software and R-studio were used for statistical and data analyses. RESULTS AND LIMITATIONS: Transcriptomic data from taxane-exposed human mCRPC tumors correlate with a marked negative enrichment of apoptosis and inflammatory response pathways accompanied by a marked downregulation of CXCR2 and BCL-2. Mechanistically, we show that docetaxel inhibits CXCR2 and that BCL-2 downregulation occurs as a downstream effect. Further, we demonstrated in experimental models that the sensitivity to cisplatin is dependent on CXCR2 and BCL-2, and that targeting them sensitizes prostate cancer (PC) cells to cisplatin. In vivo taxane-platinum combinations are highly synergistic, and previous exposure to taxanes sensitizes mCRPC tumors to second-line cisplatin treatment. CONCLUSIONS: The hitherto unappreciated attenuation of the CXCR2/BCL-2 axis in taxane-treated mCRPC patients is an acquired vulnerability with potential predictive activity for platinum-based treatments. PATIENT SUMMARY: A subset of patients with aggressive and therapy-resistant prostate cancer benefits from taxane-platinum combination chemotherapy; however, we lack the mechanistic understanding of how that synergistic effect occurs. Here, using patient data and preclinical models, we found that taxanes reduce cancer cell escape mechanisms to chemotherapy-induced cell death, hence making these cells more vulnerable to additional platinum treatment.


Assuntos
Antineoplásicos , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Neoplasias de Próstata Resistentes à Castração , Taxoides/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Docetaxel/uso terapêutico , Humanos , Masculino , Camundongos , Platina/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico
13.
EMBO Mol Med ; 12(12): e11889, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33151035

RESUMO

An open debate in antiangiogenic therapies is about their consequence on tumor invasiveness and metastasis, which is undoubtedly relevant for patients currently treated with antiangiogenics, such as renal cell carcinoma patients. To address, this we developed an extensive series of 27 patient biopsy-derived orthotopic xenograft models (Ren-PDOX) that represent inter-patient heterogeneity. In specific tumors, antiangiogenics produced increased invasiveness and metastatic dissemination, while in others aggressiveness remained unchanged. Mechanistically, species-discriminative RNA sequencing identified a tumor cell-specific differential expression profile associated with tumor progression and aggressivity in TCGA RCC patients. Gene filtering using an invasion-annotated patient series pinpointed two candidate genes, of which ALDH1A3 differentiated the pro-invasive subtype of Ren-PDOXs. Validation in an independent series of 15 antiangiogenic-treated patients confirmed that pre-treatment ALDH1A3 can significantly discriminate patients with pro-aggressive response upon treatment. Overall, results confirm that effects of antiangiogenic drugs on tumor invasion and metastasis are heterogeneous and may profoundly affect the natural progression of tumors and promote malignancy. Furthermore, we identify a specific molecular biomarker that could be used to select patients that better benefit from treatment.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Modelos Biológicos , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Nus , Medicina de Precisão , Ensaios Antitumorais Modelo de Xenoenxerto
14.
iScience ; 23(7): 101296, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32622267

RESUMO

Proper immune system function hinders cancer development, but little is known about whether genetic variants linked to cancer risk alter immune cells. Here, we report 57 cancer risk loci associated with differences in immune and/or stromal cell contents in the corresponding tissue. Predicted target genes show expression and regulatory associations with immune features. Polygenic risk scores also reveal associations with immune and/or stromal cell contents, and breast cancer scores show consistent results in normal and tumor tissue. SH2B3 links peripheral alterations of several immune cell types to the risk of this malignancy. Pleiotropic SH2B3 variants are associated with breast cancer risk in BRCA1/2 mutation carriers. A retrospective case-cohort study indicates a positive association between blood counts of basophils, leukocytes, and monocytes and age at breast cancer diagnosis. These findings broaden our knowledge of the role of the immune system in cancer and highlight promising prevention strategies for individuals at high risk.

15.
Oncogene ; 39(30): 5252-5266, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32561851

RESUMO

In response to genotoxic stress, multiple kinase signaling cascades are activated, many of them directed towards the tumor suppressor p53, which coordinates the DNA damage response (DDR). Defects in DDR pathways lead to an accumulation of mutations that can promote tumorigenesis. Emerging evidence implicates multiple members of the NimA-related kinase (NEK) family (NEK1, NEK10, and NEK11) in the DDR. Here, we describe a function for NEK10 in the regulation of p53 transcriptional activity through tyrosine phosphorylation. NEK10 loss increases cellular proliferation by modulating the p53-dependent transcriptional output. NEK10 directly phosphorylates p53 on Y327, revealing NEK10's unexpected substrate specificity. A p53 mutant at this site (Y327F) acts as a hypomorph, causing an attenuated p53-mediated transcriptional response. Consistently, NEK10-deficient cells display heightened sensitivity to DNA-damaging agents. Further, a combinatorial score of NEK10 and TP53-target gene expression is an independent predictor of a favorable outcome in breast cancers.


Assuntos
Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Mutação , Quinases Relacionadas a NIMA/genética , Proteína Supressora de Tumor p53/genética , Células A549 , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Deleção de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HEK293 , Humanos , Células MCF-7 , Quinases Relacionadas a NIMA/deficiência , Fosforilação/efeitos dos fármacos , Especificidade por Substrato , Proteína Supressora de Tumor p53/metabolismo , Tirosina/genética , Tirosina/metabolismo
16.
EMBO Mol Med ; 12(6): e11217, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32400970

RESUMO

Mitochondrial metabolism and the generation of reactive oxygen species (ROS) contribute to the acquisition of DNA mutations and genomic instability in cancer. How genomic instability influences the metabolic capacity of cancer cells is nevertheless poorly understood. Here, we show that homologous recombination-defective (HRD) cancers rely on oxidative metabolism to supply NAD+ and ATP for poly(ADP-ribose) polymerase (PARP)-dependent DNA repair mechanisms. Studies in breast and ovarian cancer HRD models depict a metabolic shift that includes enhanced expression of the oxidative phosphorylation (OXPHOS) pathway and its key components and a decline in the glycolytic Warburg phenotype. Hence, HRD cells are more sensitive to metformin and NAD+ concentration changes. On the other hand, shifting from an OXPHOS to a highly glycolytic metabolism interferes with the sensitivity to PARP inhibitors (PARPi) in these HRD cells. This feature is associated with a weak response to PARP inhibition in patient-derived xenografts, emerging as a new mechanism to determine PARPi sensitivity. This study shows a mechanistic link between two major cancer hallmarks, which in turn suggests novel possibilities for specifically treating HRD cancers with OXPHOS inhibitors.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Carcinoma Epitelial do Ovário , Feminino , Recombinação Homóloga , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Estresse Oxidativo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
17.
Cancers (Basel) ; 12(2)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012804

RESUMO

The transcription factor EVI1 plays an oncogenic role in several types of neoplasms by promoting aggressive cancer features. EVI1 contributes to epigenetic regulation and transcriptional control, and its overexpression has been associated with enhanced PI3K-AKT-mTOR signaling in some settings. These observations raise the possibility that EVI1 influences the prognosis and everolimus-based therapy outcome of clear cell renal cell carcinoma (ccRCC). Here, gene expression and protein immunohistochemical studies of ccRCC show that EVI1 overexpression is associated with advanced disease features and with poorer outcome-particularly in the CC-e.3 subtype defined by The Cancer Genome Atlas. Overexpression of an oncogenic EVI1 isoform in RCC cell lines confers substantial resistance to everolimus. The EVI1 rs1344555 genetic variant is associated with poorer survival and greater progression of metastatic ccRCC patients treated with everolimus. This study leads us to propose that evaluation of EVI1 protein or gene expression, and of EVI1 genetic variants may help improve estimates of prognosis and the benefit of everolimus-based therapy in ccRCC.

18.
Cancers (Basel) ; 11(10)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614664

RESUMO

In recent years, an increasing number of studies have shown that elevated expression of cyclin dependent kinase (Cdk5) contributes to the oncogenic initiation and progression of many types of cancers. In this study, we investigated the expression pattern of Cdk5 in colorectal cancer (CRC) cell lines and in a large number of tumor samples in order to evaluate its relevance in this pathogenesis and possible use as a prognostic marker. We found that Cdk5 is highly expressed and activated in CRC cell lines and that silencing of the kinase decreases their migration ability. In tumor tissues, Cdk5 is overexpressed compared to normal tissues due to a copy number gain. In patients with localized disease, we found that high Cdk5 levels correlate with poor prognosis, while in the metastatic setting, this was only the case for patients receiving an oxaliplatin-based treatment. When exploring the Cdk5 levels in the consensus molecular subtypes (CMS), we found the lowest levels in subtype 1, where high Cdk5 again was associated with a poorer prognosis. In conclusion, we confirm that Cdk5 is involved in CRC and disease progression and that it could serve as a prognostic and predictive biomarker in this disease.

19.
Cancer Res ; 79(16): 4258-4270, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31213465

RESUMO

Taxanes are the mainstay of treatment in triple-negative breast cancer (TNBC), with de novo and acquired resistance limiting patient's survival. To investigate the genetic basis of docetaxel resistance in TNBC, exome sequencing was performed on matched TNBC patient-derived xenografts (PDX) sensitive to docetaxel and their counterparts that developed resistance in vivo upon continuous drug exposure. Most mutations, small insertions/deletions, and copy number alterations detected in the initial TNBC human metastatic samples were maintained after serial passages in mice and emergence of resistance. We identified a chromosomal amplification of chr12p in a human BRCA1-mutated metastatic sample and the derived chemoresistant PDX, but not in the matched docetaxel-sensitive PDX tumor. Chr12p amplification was validated in a second pair of docetaxel-sensitive/resistant BRCA1-mutated PDXs and after short-term docetaxel treatment in several TNBC/BRCA1-mutated PDXs and cell lines, as well as during metastatic recurrence in a patient with BRCA1-mutated breast cancer who had progressed on docetaxel treatment. Analysis of clinical data indicates an association between chr12p amplification and patients with TNBC/basal-like breast cancer, a BRCA1 mutational signature, and poor survival after chemotherapy. Detection of chr12p amplification in a cohort of TNBC PDX models was associated with an improved response to carboplatin. Our findings reveal tumor clonal dynamics during chemotherapy treatments and suggest that a preexisting population harboring chr12p amplification is associated with the emergence of docetaxel resistance and carboplatin responsiveness in TNBC/BRCA1-mutated tumors. SIGNIFICANCE: Chr12p copy number gains indicate rapid emergence of resistance to docetaxel and increased sensitivity to carboplatin, therefore sequential docetaxel/carboplatin treatment could improve survival in TNBC/BRCA1 patients. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/16/4258/F1.large.jpg.


Assuntos
Carboplatina/farmacologia , Cromossomos Humanos Par 12 , Docetaxel/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Animais , Proteína BRCA1/genética , Linhagem Celular Tumoral , Exoma , Feminino , Humanos , Camundongos , Mutação , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/mortalidade , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Cancer Epidemiol ; 61: 129-132, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31238232

RESUMO

INTRODUCTION: The current availability of genomic information represents an opportunity to develop new strategies for early detection of cancer. New molecular tests for endometrial cancer may improve performance and failure rates of histological aspirate-based diagnosis, and provide promising perspectives for a potential screening scenario. However, the selection of relevant biomarkers to develop efficient strategies can be a challenge. MATERIALS AND METHODS: We developed an algorithm to identify the largest number of patients with endometrial cancer using the minimum number of somatic mutations based on The Cancer Genome Atlas (TCGA) dataset. RESULTS: The algorithm provided the number of subjects with mutations (sensitivity) for a given number of biomarkers included in the signature. For instance, by evaluating the 50 most representative point mutations, up to 81.9% of endometrial cancers can be identified in the TCGA dataset. At gene level, a 92.9% sensitivity can be obtained by interrogating five genes. DISCUSSION: We developed a computational method to aid in the selection of relevant genomic biomarkers in endometrial cancer that can be adapted to other cancer types or diseases.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias do Endométrio/diagnóstico , Genômica/métodos , Algoritmos , Feminino , Humanos , Mutação
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