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1.
Cancer Res Commun ; 3(11): 2412-2419, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37888903

RESUMO

The cGAS/STING cytosolic DNA-sensing pathway plays a significant role in antitumor immunity. Expression of STING is tightly regulated and commonly reduced or defective in many types of cancer. We have identified SIX4 as a significant regulator of STING expression in colon cancer cells. We showed that knockout of SIX4 decreased STING expression at the mRNA and protein levels while ectopic expression of SIX4 increased STING expression. Depletion of SIX4 led to attenuated STING activation and downstream signaling. Reexpression of SIX4 or ectopic expression of STING in SIX4 knockout cells reversed the effect. Ectopic expression of SIX4 enhanced DMXAA and cGAMP-induced STING activation and downstream signaling. Importantly, decrease of SIX4 expression substantially decreased tumor infiltration of CD8+ T cells and reduced the efficacy of PD-1 antibodies to diminish tumor growth in immune competent mice in vivo. Finally, analysis of The Cancer Genome Atlas colon cancer dataset indicated that tumors with high SIX4 expression were significantly enriched in the Inflammatory Response pathway. SIX4 expression also correlated with expression of multiple IFN-stimulated genes, inflammatory cytokines, and CD8A. Taken together, our results implicate that SIX4 is a principal regulator of STING expression in colon cancer cells, providing an additional mechanism and genetic marker to predict effective immune checkpoint blockade therapy responses. SIGNIFICANCE: Our studies demonstrate that SIX4 is an important regulator of STING expression, providing a genetic marker or a therapeutic target to predict or enhance immune checkpoint blockade therapy responses in colon cancer.


Assuntos
Neoplasias do Colo , Inibidores de Checkpoint Imunológico , Camundongos , Animais , Marcadores Genéticos , Transdução de Sinais , Citocinas , Neoplasias do Colo/genética
2.
Cell Death Differ ; 30(9): 2078-2091, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37537305

RESUMO

The discrimination of protein biological functions in different phases of the cell cycle is limited by the lack of experimental approaches that do not require pre-treatment with compounds affecting the cell cycle progression. Therefore, potential cycle-specific biological functions of a protein of interest could be biased by the effects of cell treatments. The OsTIR1/auxin-inducible degron (AID) system allows "on demand" selective and reversible protein degradation upon exposure to the phytohormone auxin. In the current format, this technology does not allow to study the effect of acute protein depletion selectively in one phase of the cell cycle, as auxin similarly affects all the treated cells irrespectively of their proliferation status. Therefore, the AID system requires coupling with cell synchronization techniques, which can alter the basal biological status of the studied cell population, as with previously available approaches. Here, we introduce a new AID system to Regulate OsTIR1 Levels based on the Cell Cycle Status (ROLECCS system), which induces proteolysis of both exogenously transfected and endogenous gene-edited targets in specific phases of the cell cycle. We validated the ROLECCS technology by down regulating the protein levels of TP53, one of the most studied tumor suppressor genes, with a widely known role in cell cycle progression. By using our novel tool, we observed that TP53 degradation is associated with increased number of micronuclei, and this phenotype is specifically achieved when TP53 is lost in S/G2/M phases of the cell cycle, but not in G1. Therefore, we propose the use of the ROLECCS system as a new improved way of studying the differential roles that target proteins may have in specific phases of the cell cycle.


Assuntos
Ácidos Indolacéticos , Proteínas , Ácidos Indolacéticos/farmacologia , Ácidos Indolacéticos/metabolismo , Proteólise , Proteínas/metabolismo , Ciclo Celular , Divisão Celular
3.
Mol Oncol ; 17(5): 839-856, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35838343

RESUMO

Small-cell lung cancer (SCLC) is an aggressive neuroendocrine subtype of lung cancer with poor patient prognosis. However, the mechanisms that regulate SCLC progression and metastasis remain undefined. Here, we show that the expression of the slit guidance ligand 2 (SLIT2) tumor suppressor gene is reduced in SCLC tumors relative to adjacent normal tissue. In addition, the expression of the SLIT2 receptor, roundabout guidance receptor 1 (ROBO1), is upregulated. We find a positive association between SLIT2 expression and the Yes1 associated transcriptional regulator (YAP1)-expressing SCLC subtype (SCLC-Y), which shows a better prognosis. Using genetically engineered SCLC cells, adenovirus gene therapy, and preclinical xenograft models, we show that SLIT2 overexpression or the deletion of ROBO1 restricts tumor growth in vitro and in vivo. Mechanistic studies revealed significant inhibition of myeloid-derived suppressor cells (MDSCs) and M2-like tumor-associated macrophages (TAMs) in the SCLC tumors. In addition, SLIT2 enhances M1-like and phagocytic macrophages. Molecular analysis showed that ROBO1 knockout or SLIT2 overexpression suppresses the transforming growth factor beta 1 (TGF-ß1)/ß-catenin signaling pathway in both tumor cells and macrophages. Overall, we find that SLIT2 and ROBO1 have contrasting effects on SCLC tumors. SLIT2 suppresses, whereas ROBO1 promotes, SCLC growth by regulating the Tgf-ß1/glycogen synthase kinase-3 beta (GSK3)/ß-catenin signaling pathway in tumor cells and TAMs. These studies indicate that SLIT2 could be used as a novel therapeutic agent against aggressive SCLC.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Fator de Crescimento Transformador beta1/farmacologia , beta Catenina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/farmacologia , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Transdução de Sinais , Carcinoma de Pequenas Células do Pulmão/genética , Neoplasias Pulmonares/genética , Macrófagos/metabolismo
4.
Nucleic Acids Res ; 50(12): 7048-7066, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35736218

RESUMO

DICER1 syndrome is a cancer pre-disposition disorder caused by mutations that disrupt the function of DICER1 in miRNA processing. Studying the molecular, cellular and oncogenic effects of these mutations can reveal novel mechanisms that control cell homeostasis and tumor biology. Here, we conduct the first analysis of pathogenic DICER1 syndrome allele from the DICER1 3'UTR. We find that the DICER1 syndrome allele, rs1252940486, abolishes interaction with the PUMILIO RNA binding protein with the DICER1 3'UTR, resulting in the degradation of the DICER1 mRNA by AUF1. This single mutational event leads to diminished DICER1 mRNA and protein levels, and widespread reprogramming of miRNA networks. The in-depth characterization of the rs1252940486 DICER1 allele, reveals important post-transcriptional regulatory events that control DICER1 levels.


Assuntos
MicroRNAs , RNA Mensageiro , MicroRNAs/genética
5.
NPJ Precis Oncol ; 6(1): 29, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35468996

RESUMO

Leiomyosarcoma (LMS) is a rare, aggressive, mesenchymal tumor. Subsets of LMS have been identified to harbor genomic alterations associated with homologous recombination deficiency (HRD); particularly alterations in BRCA2. Whereas genomic loss of heterozygosity (gLOH) has been used as a surrogate marker of HRD in other solid tumors, the prognostic or clinical value of gLOH in LMS (gLOH-LMS) remains poorly defined. We explore the genomic drivers associated with gLOH-LMS and their clinical import. Although the distribution of gLOH-LMS scores are similar to that of carcinomas, outside of BRCA2, there was no overlap with previously published gLOH-associated genes from studies in carcinomas. We note that early stage tumors with elevated gLOH demonstrated a longer disease-free interval following resection in LMS patients. Taken together, and despite similarities to carcinomas in gLOH distribution and clinical import, gLOH-LMS are driven by different genomic signals. Additional studies will be required to isolate and confirm the unique differences in biological factors driving these differences.

6.
Sci Rep ; 12(1): 4082, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260723

RESUMO

The Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV), is a highly infectious RNA virus. A percentage of patients develop coronavirus disease 2019 (COVID-19) after infection, whose symptoms include fever, cough, shortness of breath and fatigue. Acute and life-threatening respiratory symptoms are experienced by 10-20% of symptomatic patients, particularly those with underlying medical conditions. One of the main challenges in the containment of COVID-19 is the identification and isolation of asymptomatic/pre-symptomatic individuals. A number of molecular assays are currently used to detect SARS-CoV-2. Many of them can accurately test hundreds or even thousands of patients every day. However, there are presently no testing platforms that enable more than 10,000 tests per day. Here, we describe the foundation for the REcombinase Mediated BaRcoding and AmplificatioN Diagnostic Tool (REMBRANDT), a high-throughput Next Generation Sequencing-based approach for the simultaneous screening of over 100,000 samples per day. The REMBRANDT protocol includes direct two-barcoded amplification of SARS-CoV-2 and control amplicons using an isothermal reaction, and the downstream library preparation for Illumina sequencing and bioinformatics analysis. This protocol represents a potentially powerful approach for community screening of COVID-19 that may be modified for application to any infectious or non-infectious genome.


Assuntos
COVID-19/diagnóstico , Proteínas de Ligação a DNA/metabolismo , Proteínas de Membrana/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , SARS-CoV-2/genética , Proteínas Virais/metabolismo , COVID-19/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Programas de Rastreamento , RNA Viral/análise , RNA Viral/metabolismo , SARS-CoV-2/isolamento & purificação
7.
JCO Precis Oncol ; 6: e2100211, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35108033

RESUMO

PURPOSE: Soft tissue and bone sarcomas are rare malignancies that exhibit significant pathologic and molecular heterogeneity. Deregulation of the CDKN2A-CCND-CDK4/6-retinoblastoma 1 (Rb) pathway is frequently observed in about 25% of unselected sarcomas and is pathognomonic for specific sarcoma subtypes. This genomic specificity has fueled the clinical evaluation of selective CDK4/6 inhibitors in sarcomas. Here, we highlight successes, opportunities, and future challenges for using CDK4/6 inhibitors to treat sarcoma. MATERIALS AND METHODS: This review summarizes the current evidence for the use of CDK4/6 inhibitors in sarcoma while identifying molecular rationale and predictive biomarkers that provide the foundation for targeting the CDK4/6 pathway in sarcoma. A systematic review was performed of articles indexed in the PubMed database and the National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov). For each sarcoma subtype, we discuss the preclinical rationale, case reports, and available clinical trials data. RESULTS: Despite promising clinical outcomes in a subset of sarcomas, resistance to CDK4/6 inhibitors results in highly heterogeneous clinical outcomes. Current clinical data support the use of CDK4/6 inhibitors in subsets of sarcoma primarily driven by CDK4/6 deregulation. When dysregulation of the Rb pathway is a secondary driver of sarcoma, combination therapy with CDK4/6 inhibition may be an option. Developing strategies to identify responders and the mechanisms that drive resistance is important to maximize the clinical utility of these drugs in patients with sarcoma. Potential biomarkers that indicate CDK4/6 inhibitor sensitivity in sarcoma include CDK4, CCND, CCNE, RB1, E2F1, and CDKN2A. CONCLUSION: CDK4/6 inhibitors represent a major breakthrough for targeted cancer treatment. CDK4/6 inhibitor use in sarcoma has led to limited, but significant, early clinical success. Targeted future clinical research will be key to unlocking the potential of CDK4/6 inhibition in sarcoma.


Assuntos
Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Sarcoma , Neoplasias de Tecidos Moles , Ensaios Clínicos como Assunto , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/metabolismo , Genômica/métodos , Humanos , Sarcoma/tratamento farmacológico , Sarcoma/enzimologia , Neoplasias de Tecidos Moles/enzimologia , Estados Unidos
8.
J Exp Clin Cancer Res ; 41(1): 54, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35135586

RESUMO

BACKGROUND: Molecular mechanisms underlying inflammation-associated breast tumor growth are poorly studied. S100A7, a pro-inflammatory molecule has been shown to enhance breast cancer growth and metastasis. However, the S100A7-mediated molecular mechanisms in enhancing tumor growth and metastasis are unclear. METHODS: Human breast cancer tissue and plasma samples were used to analyze the expression of S100A7, cPLA2, and PGE2. S100A7-overexpressing or downregulated human metastatic breast cancer cells were used to evaluate the S100A7-mediated downstream signaling mechanisms. Bi-transgenic mS100a7a15 overexpression, TNBC C3 (1)/Tag transgenic, and humanized patient-derived xenograft mouse models and cPLA2 inhibitor (AACOCF3) were used to investigate the role of S100A7/cPLA2/PGE2 signaling in tumor growth and metastasis. Additionally, CODEX, a highly advanced multiplexed imaging was employed to delineate the effects of S100A7/cPLA2 inhibition on the recruitment of various immune cells. RESULTS: In this study, we found that S100A7 and cPLA2 are highly expressed and correlate with decreased overall survival in breast cancer patients. Further mechanistic studies revealed that S100A7/RAGE signaling promotes the expression of cPLA2 to mediate its oncogenic effects. Pharmacological inhibition of cPLA2 suppressed S100A7-mediated tumor growth and metastasis in multiple pre-clinical models including transgenic and humanized patient-derived xenograft (PDX) mouse models. The attenuation of cPLA2 signaling reduced S100A7-mediated recruitment of immune-suppressive myeloid cells in the tumor microenvironment (TME). Interestingly, we discovered that the S100A7/cPLA2 axis enhances the immunosuppressive microenvironment by increasing prostaglandin E2 (PGE2). Furthermore, CO-Detection by indEXing (CODEX) imaging-based analyses revealed that cPLA2 inhibition increased the infiltration of activated and proliferating CD4+ and CD8+ T cells in the TME. In addition, CD163+ tumor associated-macrophages were positively associated with S100A7 and cPLA2 expression in malignant breast cancer patients. CONCLUSIONS: Our study provides new mechanistic insights on the cross-talk between S100A7/cPLA2 in enhancing breast tumor growth and metastasis by generating an immunosuppressive TME that inhibits the infiltration of cytotoxic T cells. Furthermore, our studies indicate that S100A7/cPLA2 could be used as novel prognostic marker and cPLA2 inhibitors as promising drugs against S100A7-overexpressing aggressive breast cancer.


Assuntos
Neoplasias da Mama/genética , Fosfolipases A2 Citosólicas/antagonistas & inibidores , Proteína A7 Ligante de Cálcio S100/metabolismo , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Microambiente Tumoral
9.
Int J Mol Sci ; 23(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35008958

RESUMO

Worldwide, the number of cancer-related deaths continues to increase due to the ability of cancer cells to become chemotherapy-resistant and metastasize. For women with ovarian cancer, a staggering 70% will become resistant to the front-line therapy, cisplatin. Although many mechanisms of cisplatin resistance have been proposed, the key mechanisms of such resistance remain elusive. The RNA binding protein with multiple splicing (RBPMS) binds to nascent RNA transcripts and regulates splicing, transport, localization, and stability. Evidence indicates that RBPMS also binds to protein members of the AP-1 transcription factor complex repressing its activity. Until now, little has been known about the biological function of RBPMS in ovarian cancer. Accordingly, we interrogated available Internet databases and found that ovarian cancer patients with high RBPMS levels live longer compared to patients with low RBPMS levels. Similarly, immunohistochemical (IHC) analysis in a tissue array of ovarian cancer patient samples showed that serous ovarian cancer tissues showed weaker RBPMS staining when compared with normal ovarian tissues. We generated clustered regularly interspaced short palindromic repeats (CRISPR)-mediated RBPMS knockout vectors that were stably transfected in the high-grade serous ovarian cancer cell line, OVCAR3. The knockout of RBPMS in these cells was confirmed via bioinformatics analysis, real-time PCR, and Western blot analysis. We found that the RBPMS knockout clones grew faster and had increased invasiveness than the control CRISPR clones. RBPMS knockout also reduced the sensitivity of the OVCAR3 cells to cisplatin treatment. Moreover, ß-galactosidase (ß-Gal) measurements showed that RBPMS knockdown induced senescence in ovarian cancer cells. We performed RNAseq in the RBPMS knockout clones and identified several downstream-RBPMS transcripts, including non-coding RNAs (ncRNAs) and protein-coding genes associated with alteration of the tumor microenvironment as well as those with oncogenic or tumor suppressor capabilities. Moreover, proteomic studies confirmed that RBPMS regulates the expression of proteins involved in cell detoxification, RNA processing, and cytoskeleton network and cell integrity. Interrogation of the Kaplan-Meier (KM) plotter database identified multiple downstream-RBPMS effectors that could be used as prognostic and response-to-therapy biomarkers in ovarian cancer. These studies suggest that RBPMS acts as a tumor suppressor gene and that lower levels of RBPMS promote the cisplatin resistance of ovarian cancer cells.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Biomarcadores Tumorais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Splicing de RNA , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética
11.
Transl Oncol ; 14(11): 101197, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34388693

RESUMO

Immunotherapy has improved the prognosis for many melanoma patients; however, our capacity to predict patient responses and to understand the biological differences between patients who will or will not respond is limited. Gene expression profiling of tumors from patients who respond to immunotherapy has focused on deriving primarily immune-related signatures; however, these have shown limited predictive power. Recent studies have highlighted the role of RNA editing in modulating resistance to immunotherapy. To evaluate the utility of RNA editing activity as a discriminative tool in predicting immunotherapy response, we conducted a retrospective analysis of RNA-sequencing data from melanoma patients treated with Pembrolizumab or Nivolumab. Here, we developed RNA editing signatures that can identify patients who will respond to immunotherapy with very high accuracy and confidence. Our analysis demonstrates that RNA editing is a strong discriminative tool for examining sensitivity of melanoma patients to immunotherapy.

12.
Commun Biol ; 4(1): 977, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404904

RESUMO

Inactivation of RB is one of the hallmarks of cancer, however gaps remain in our understanding of how RB-loss changes human cells. Here we show that pRB-depletion results in cellular reprogramming, we quantitatively measured how RB-depletion altered the transcriptional, proteomic and metabolic output of non-tumorigenic RPE1 human cells. These profiles identified widespread changes in metabolic and cell stress response factors previously linked to E2F function. In addition, we find a number of additional pathways that are sensitive to RB-depletion that are not E2F-regulated that may represent compensatory mechanisms to support the growth of RB-depleted cells. To determine whether these molecular changes are also present in RB1-/- tumors, we compared these results to Retinoblastoma and Small Cell Lung Cancer data, and identified widespread conservation of alterations found in RPE1 cells. To define which of these changes contribute to the growth of cells with de-regulated E2F activity, we assayed how inhibiting or depleting these proteins affected the growth of RB1-/- cells and of Drosophila E2f1-RNAi models in vivo. From this analysis, we identify key metabolic pathways that are essential for the growth of pRB-deleted human cells.


Assuntos
Neoplasias da Retina/fisiopatologia , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/fisiopatologia , Ubiquitina-Proteína Ligases/genética , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Proteínas de Ligação a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
14.
Chem Rev ; 121(13): 7398-7467, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34038115

RESUMO

RNA nanotechnology is the bottom-up self-assembly of nanometer-scale architectures, resembling LEGOs, composed mainly of RNA. The ideal building material should be (1) versatile and controllable in shape and stoichiometry, (2) spontaneously self-assemble, and (3) thermodynamically, chemically, and enzymatically stable with a long shelf life. RNA building blocks exhibit each of the above. RNA is a polynucleic acid, making it a polymer, and its negative-charge prevents nonspecific binding to negatively charged cell membranes. The thermostability makes it suitable for logic gates, resistive memory, sensor set-ups, and NEM devices. RNA can be designed and manipulated with a level of simplicity of DNA while displaying versatile structure and enzyme activity of proteins. RNA can fold into single-stranded loops or bulges to serve as mounting dovetails for intermolecular or domain interactions without external linking dowels. RNA nanoparticles display rubber- and amoeba-like properties and are stretchable and shrinkable through multiple repeats, leading to enhanced tumor targeting and fast renal excretion to reduce toxicities. It was predicted in 2014 that RNA would be the third milestone in pharmaceutical drug development. The recent approval of several RNA drugs and COVID-19 mRNA vaccines by FDA suggests that this milestone is being realized. Here, we review the unique properties of RNA nanotechnology, summarize its recent advancements, describe its distinct attributes inside or outside the body and discuss potential applications in nanotechnology, medicine, and material science.


Assuntos
Nanomedicina/métodos , Neoplasias/tratamento farmacológico , Estabilidade de RNA , RNA/química , Animais , Humanos , Terapia de Alvo Molecular , Termodinâmica
15.
Australas Psychiatry ; 29(3): 299-304, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32586110

RESUMO

OBJECTIVES: To understand the impact of 3-monthly treatment with paliperidone palmitate on patient management, including non-adherence and relapse, from a psychiatrist and nurse perspective for 73 patients enrolled in a patient familiarisation programme (PFP) in New Zealand. METHODS: An online questionnaire was sent to clinicians with at least 6 months of regular interaction with PFP patients. Questions addressed treatment effectiveness and patient management changes. Analyses are descriptive only and do not represent patient or carer perspectives. RESULTS: Seven psychiatrists, representing 58 of 73 (79.5%) of patients, and 17 nurses responded to the survey. Psychiatrists were satisfied with efficacy and tolerability and relapse prevention. Treatment goals were either 'met' (2/7; 28.6%) or 'exceeded' (5/7; 71.4%). The focus on adherence issues decreased and the focus on life areas and recovery goals increased. CONCLUSIONS: From the clinician perspective, 3-monthly paliperidone palmitate offers patients the potential to remain adherent and improve social functioning.


Assuntos
Antipsicóticos , Esquizofrenia , Antipsicóticos/efeitos adversos , Cuidadores , Humanos , Nova Zelândia , Palmitato de Paliperidona/efeitos adversos , Esquizofrenia/tratamento farmacológico
16.
Cancers (Basel) ; 12(9)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937789

RESUMO

MENIN is a scaffold protein encoded by the MEN1 gene that functions in multiple biological processes, including cell proliferation, migration, gene expression, and DNA damage repair. MEN1 is a tumor suppressor gene, and mutations that disrupts MEN1 function are common to many tumor types. Mutations within MEN1 may also be inherited (germline). Many of these inherited mutations are associated with a number of pathogenic syndromes of the parathyroid and pancreas, and some also predispose patients to hyperplasia. In this study, we cataloged the reported germline mutations from the ClinVar database and compared them with the somatic mutations detected in cancers from the Catalogue of Somatic Mutations in Cancer (COSMIC) database. We then used statistical software to determine the probability of mutations being pathogenic or driver. Our data show that many confirmed germline mutations do not appear in tumor samples. Thus, most mutations that disable MEN1 function in tumors are somatic in nature. Furthermore, of the germline mutations that do appear in tumors, only a fraction has the potential to be pathogenic or driver mutations.

17.
Cancer Discov ; 10(9): 1296-1311, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32371478

RESUMO

The molecular mechanisms leading to resistance to PD-1 blockade are largely unknown. Here, we characterize tumor biopsies from a patient with melanoma who displayed heterogeneous responses to anti-PD-1 therapy. We observe that a resistant tumor exhibited a loss-of-function mutation in the tumor suppressor gene FBXW7, whereas a sensitive tumor from the same patient did not. Consistent with a functional role in immunotherapy response, inactivation of Fbxw7 in murine tumor cell lines caused resistance to anti-PD-1 in immunocompetent animals. Loss of Fbxw7 was associated with altered immune microenvironment, decreased tumor-intrinsic expression of the double-stranded RNA (dsRNA) sensors MDA5 and RIG1, and diminished induction of type I IFN and MHC-I expression. In contrast, restoration of dsRNA sensing in Fbxw7-deficient cells was sufficient to sensitize them to anti-PD-1. Our results thus establish a new role for the commonly inactivated tumor suppressor FBXW7 in viral sensing and sensitivity to immunotherapy. SIGNIFICANCE: Our findings establish a role of the commonly inactivated tumor suppressor FBXW7 as a genomic driver of response to anti-PD-1 therapy. Fbxw7 loss promotes resistance to anti-PD-1 through the downregulation of viral sensing pathways, suggesting that therapeutic reactivation of these pathways could improve clinical responses to checkpoint inhibitors in genomically defined cancer patient populations.This article is highlighted in the In This Issue feature, p. 1241.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Proteína 7 com Repetições F-Box-WD/genética , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Linhagem Celular Tumoral/transplante , Proteína DEAD-box 58/genética , Proteína DEAD-box 58/metabolismo , Modelos Animais de Doenças , Proteína 7 com Repetições F-Box-WD/metabolismo , Regulação Neoplásica da Expressão Gênica/imunologia , Células HeLa , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/metabolismo , Mutação com Perda de Função , Masculino , Camundongos , Mutagênese Sítio-Dirigida , Receptor de Morte Celular Programada 1/antagonistas & inibidores , RNA de Cadeia Dupla/imunologia , RNA de Cadeia Dupla/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
18.
Nat Commun ; 10(1): 5157, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727958

RESUMO

Most targeted cancer therapies fail to achieve complete tumor regressions or attain durable remissions. To understand why these treatments fail to induce robust cytotoxic responses despite appropriately targeting oncogenic drivers, here we systematically interrogated the dependence of cancer cells on the BCL-2 family of apoptotic proteins after drug treatment. We observe that multiple targeted therapies, including BRAF or EGFR inhibitors, rapidly deplete the pro-apoptotic factor NOXA, thus creating a dependence on the anti-apoptotic protein MCL-1. This adaptation requires a pathway leading to destabilization of the NOXA mRNA transcript. We find that interruption of this mechanism of anti-apoptotic adaptive resistance dramatically increases cytotoxic responses in cell lines and a murine melanoma model. These results identify NOXA mRNA destabilization/MCL-1 adaptation as a non-genomic mechanism that limits apoptotic responses, suggesting that sequencing of MCL-1 inhibitors with targeted therapies could overcome such widespread and clinically important resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas c-bcl-2/genética , Estabilidade de RNA/genética , Animais , Apoptose , Sequência de Bases , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos Nus , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Tristetraprolina/metabolismo
19.
Nucleic Acids Res ; 47(11): 5490-5501, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31076772

RESUMO

RNA is an essential player in almost all biological processes, and has an ever-growing number of roles in regulating cellular growth and organization. RNA functions extend far beyond just coding for proteins and RNA has been shown to function in signaling events, chromatin organization and transcriptional regulation. Dissecting how the complex network of RNA-binding proteins (RBPs) and regulatory RNAs interact with their substrates within the cell is a real, but exciting, challenge for the RNA community. Investigating these biological questions has fueled the development of new quantitative technologies to measure how RNA and RBPs interact both locally and on a global scale. In this review, we provide an assessment of available approaches to enable researchers to select the protocol most applicable for their experimental question.


Assuntos
Proteínas de Ligação a RNA/genética , RNA/genética , Sítios de Ligação , Reagentes de Ligações Cruzadas , Regulação da Expressão Gênica , Processos Fotoquímicos/efeitos da radiação , Domínios Proteicos , RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Raios Ultravioleta
20.
Front Oncol ; 9: 221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31058073

RESUMO

Retinoblastoma is a rare pediatric tumor of the retina, caused by the homozygous loss of the Retinoblastoma 1 (RB1) tumor suppressor gene. Previous microarray studies have identified changes in the expression profiles of coding genes; however, our understanding of how non-coding genes change in this tumor is absent. This is an important area of research, as in many adult malignancies, non-coding genes including LNC-RNAs are used as biomarkers to predict outcome and/or relapse. To establish a complete and in-depth RNA profile, of both coding and non-coding genes, in Retinoblastoma tumors, we conducted RNA-seq from a cohort of tumors and normal retina controls. This analysis identified widespread transcriptional changes in the levels of both coding and non-coding genes. Unexpectedly, we also found rare RNA fusion products resulting from genomic alterations, specific to Retinoblastoma tumor samples. We then determined whether these gene expression changes, of both coding and non-coding genes, were also found in a completely independent Retinoblastoma cohort. Using our dataset, we then profiled the potential effects of deregulated LNC-RNAs on the expression of neighboring genes, the entire genome, and on mRNAs that contain a putative area of homology. This analysis showed that most deregulated LNC-RNAs do not act locally to change the transcriptional environment, but potentially function to modulate genes at distant sites. From this analysis, we selected a strongly down-regulated LNC-RNA in Retinoblastoma, DRAIC, and found that restoring DRAIC RNA levels significantly slowed the growth of the Y79 Retinoblastoma cell line. Collectively, our work has generated the first non-coding RNA profile of Retinoblastoma tumors and has found that these tumors show widespread transcriptional deregulation.

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