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1.
Pancreatology ; 24(1): 78-87, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042675

RESUMO

BACKGROUND: Endoscopic ultrasound-guided tissue acquisition (EUS-TA) has high sensitivity for the pathological diagnosis of pancreatic masses, but also a high false-negative rate. K-ras gene mutations occur in over 75 % of pancreatic ductal adenocarcinomas (PDAC), and this meta-analysis evaluated the utility of detecting K-ras gene mutations from EUS-TA specimens for the diagnosis of PDAC. METHODS: Relevant studies in PubMed, the Cochrane Library, and Web of Science were systematically searched. Meta-analysis was performed on data from the selected studies using a bivariate model to provide pooled values of sensitivity, specificity, and their 95 % confidence intervals (CIs). RESULTS: This meta-analysis included 1521 patients (from 10 eligible studies) who underwent EUS-TA with K-ras gene mutation analysis for diagnosis of pancreatic solid masses. The pooled estimates of sensitivity and specificity were 76.6 % (95 % CI, 70.9-81.5 %) and 97.0 % (95 % CI, 94.0-98.5 %), respectively, for pathological diagnosis, 75.9 % (95 % CI 69.5-81.4 %) and 95.3 % (95 % CI, 92.3-97.2 %) for K-ras gene mutation analysis, and 88.7 % (95 % CI 87.1-91.7 %) and 94.9 % (95 % CI, 91.5-97.0 %) for pathological diagnosis in combination with K-ras gene mutation analysis. The sensitivity for diagnosis of PDAC was significantly higher for pathological diagnosis in combination with K-ras gene mutation analysis than for pathological diagnosis or K-ras gene mutation analysis alone (both, p < 0.001). There was no difference in specificity between pathological diagnosis in combination with K-ras gene mutation analysis and both either (p = 0.234, 0.945, respectively). CONCLUSIONS: K-ras gene mutation analysis in combination with to pathological diagnosis of EUS-TA increases the accuracy of differential diagnosis of PDAC.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Genes ras/genética , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/genética , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Mutação
3.
Pathologie (Heidelb) ; 43(Suppl 1): 36-41, 2022 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-36255446

RESUMO

BACKGROUND: Oncogenic driver mutations in RAS/RAF oncogenes are frequent in colorectal cancer (CRC). The presence of different subclones within a single tumor can lead to treatment failure in anti-EGFR/epidermal growth factor receptor-directed antibody therapies. The identification of different subclones and their mutational profiles within a single tumor and the identification of morphologically distinct tumor areas might help to unravel novel aspects of tumor biology and therapy resistance. OBJECTIVES: The aim of this study was to identify intratumoral heterogeneity in CRC by using laser microdissection (LMD) in comparison to the routinely used method. We hereby applied LMD to identify and investigate tumor heterogeneity in CRC. METHODS: We established LMD and purified DNA from several morphologically distinct tumor areas (n = 13) in CRCs from 2 patients and compared the results from routine testing to our newly established LMD approach. LMD enabled the comparative analysis of small tumor areas by cutting histologically selected elements under microscopic control using a laser beam. RESULTS: In some cases, potential low-level mutations (PLLM) could not be detected using the routine method since they were masked by high-level mutations (HLM). The application of LMD enabled the identification of concomitant PLLM in NRAS and BRAF genes in the identical patient sample. CONCLUSION: LMD improved spatial resolution in the molecular analysis of CRC tumor tissue compared to routine methods. Our results confirmed the presence of molecular heterogeneity in CRC. This should be kept in mind when interpreting sequencing results, since low frequency mutations can have an impact on the effectiveness of targeted therapy.


Assuntos
Neoplasias Colorretais , Microdissecção , Humanos , Neoplasias Colorretais/genética , Genes ras/genética , Mutação , Lasers
4.
Nat Commun ; 13(1): 5632, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163168

RESUMO

Activating mutations in KRAS occur in 32% of lung adenocarcinomas (LUAD). Despite leading to aggressive disease and resistance to therapy in preclinical studies, the KRAS mutation does not predict patient outcome or response to treatment, presumably due to additional events modulating RAS pathways. To obtain a broader measure of RAS pathway activation, we developed RAS84, a transcriptional signature optimised to capture RAS oncogenic activity in LUAD. We report evidence of RAS pathway oncogenic activation in 84% of LUAD, including 65% KRAS wild-type tumours, falling into four groups characterised by coincident alteration of STK11/LKB1, TP53 or CDKN2A, suggesting that the classifications developed when considering only KRAS mutant tumours have significance in a broader cohort of patients. Critically, high RAS activity patient groups show adverse clinical outcome and reduced response to chemotherapy. Patient stratification using oncogenic RAS transcriptional activity instead of genetic alterations could ultimately assist in clinical decision-making.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Genes ras/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas ras
5.
Nat Commun ; 13(1): 5469, 2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115844

RESUMO

Oncogenic RAS mutations are common in multiple myeloma (MM), an incurable malignancy of plasma cells. However, the mechanisms of pathogenic RAS signaling in this disease remain enigmatic and difficult to inhibit therapeutically. We employ an unbiased proteogenomic approach to dissect RAS signaling in MM. We discover that mutant isoforms of RAS organize a signaling complex with the amino acid transporter, SLC3A2, and MTOR on endolysosomes, which directly activates mTORC1 by co-opting amino acid sensing pathways. MM tumors with high expression of mTORC1-dependent genes are more aggressive and enriched in RAS mutations, and we detect interactions between RAS and MTOR in MM patient tumors harboring mutant RAS isoforms. Inhibition of RAS-dependent mTORC1 activity synergizes with MEK and ERK inhibitors to quench pathogenic RAS signaling in MM cells. This study redefines the RAS pathway in MM and provides a mechanistic and rational basis to target this mode of RAS signaling.


Assuntos
Genes ras , Mieloma Múltiplo , Fatores de Transcrição , Aminoácidos/metabolismo , Genes ras/genética , Genes ras/fisiologia , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mutação , Isoformas de Proteínas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
N Engl J Med ; 387(2): 184-186, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35830646
7.
Small GTPases ; 13(1): 287-295, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35658790

RESUMO

The RAS family of small GTPases is mutated in roughly a fifth of human cancers. Hotspot point mutations at codons G12, G13, and Q61 account for 95% of all these mutations, which are well established to render the encoded proteins oncogenic. In humans, this family comprises three genes: HRAS, NRAS, and KRAS. Accumulating evidence argues that oncogenic RAS point mutations may be initiating, as they are often truncal in human tumours and capable of inducing tumorigenesis in mice. As such, there is great interest in detecting oncogenic mutation in the RAS genes to understand the origins of cancer, as well as for early detection purposes. To this end, we previously adapted the microbial ultra-sensitive Maximum Depth Sequencing (MDS) assay for the murine Kras gene, which was capable of detecting oncogenic mutations in the tissues of mice days after carcinogen exposure, essentially capturing the very first step in tumour initiation. Given this, we report here the adaption and details of this assay to detect mutations in a human KRAS sequence at an analytic sensitivity of one mutation in a million independently barcoded templates. This humanized version of MDS can thus be exploited to detect oncogenic mutations in KRAS at an incredible sensitivity and modified for the same purpose for the other RAS genes.


Assuntos
Genes ras , Neoplasias , Animais , Carcinogênese , Transformação Celular Neoplásica/genética , Genes ras/genética , Humanos , Camundongos , Mutação , Neoplasias/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
8.
J Am Coll Surg ; 235(1): 8-16, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35703957

RESUMO

BACKGROUND: Micrometastases, defined as microscopic cancer cells spatially separated from the macroscopically evident metastasis, are identified in 24% to 56% of resected colorectal liver metastases (CLMs). Somatic gene mutations have emerged as independent prognostic factors in CLM. This study aimed to determine the prognostic impact and risk factors for the presence of micrometastases, including somatic gene mutations. STUDY DESIGN: Prospective evaluation for micrometastases was performed at 2 centers in the US and France from 2015 to 2019. CLM specimens were cut radially from the tumor margin to surrounding grossly normal liver for a distance of 2 cm. Depending on CLM size, 3 to 8 specimens per patient were submitted for microscopic analysis. Somatic gene mutations were detected by next-generation sequencing. RESULTS: Among 140 patients undergoing CLM resection in the US (n = 84) and France (n = 56), 36 (26%) patients were found to have micrometastases. Five-year overall and recurrence-free survival rates with micrometastases were 39% and 0%, respectively, compared with 61% and 20% without micrometastases (both p < 0.05). In multivariable analyses, the presence of micrometastases was an independent risk factor for worse overall survival (hazard ratio 2.88, 95% CI 1.46 to 5.70, p = 0.002) and recurrence-free survival (hazard ratio 1.56, 95% CI 1.01 to 2.41, p = 0.046). In binary logistic regression analysis, RAS/TP53 co-mutation was found to significantly increase the risk of micrometastases (odds ratio 2.77, 95% CI 1.15 to 6.71, p = 0.024). CONCLUSIONS: Micrometastases are associated with significantly worse survival after CLM resection. RAS/TP53 co-mutation correlated with increased risk of micrometastases. Further studies are needed to determine strategies to eradicate micrometastases.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Genes ras/genética , Hepatectomia , Humanos , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Mutação , Micrometástase de Neoplasia , Prognóstico , Taxa de Sobrevida , Proteína Supressora de Tumor p53/genética
9.
Cell Rep ; 38(6): 110322, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35139380

RESUMO

RAS guanosine triphosphatases (GTPases) are mutated in nearly 20% of human tumors, making them an attractive therapeutic target. Following our discovery that nucleotide-free RAS (apo RAS) regulates cell signaling, we selectively target this state as an approach to inhibit RAS function. Here, we describe the R15 monobody that exclusively binds the apo state of all three RAS isoforms in vitro, regardless of the mutation status, and captures RAS in the apo state in cells. R15 inhibits the signaling and transforming activity of a subset of RAS mutants with elevated intrinsic nucleotide exchange rates (i.e., fast exchange mutants). Intracellular expression of R15 reduces the tumor-forming capacity of cancer cell lines driven by select RAS mutants and KRAS(G12D)-mutant patient-derived xenografts (PDXs). Thus, our approach establishes an opportunity to selectively inhibit a subset of RAS mutants by targeting the apo state with drug-like molecules.


Assuntos
Genes ras/genética , Mutação/genética , Nucleotídeos/metabolismo , Neoplasias Pancreáticas/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Humanos , Camundongos , Neoplasias Pancreáticas/patologia , Transdução de Sinais/genética
10.
Asian Pac J Cancer Prev ; 23(1): 125-130, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35092380

RESUMO

OBJECTIVE: Acute myeloid leukemia is caused by the clonal proliferation of undifferentiated myeloid hematopoietic precursors. AML prognosis is highly involved in the treatment response and is determined by mutations in several genes such as N-RAS. This study aims to identify the distribution of common N-RAS mutations (codons 12, 13, and 61) in AML patients using the HRM method and confirm this method's efficiency for mutation detection by comparing its results with the sequencing data as the Gold standard method. METHODS: Peripheral blood samples were taken from 50 newly diagnosed AML patients. Mononuclear cells were isolated from samples, and DNA was extracted. Then, mutation detection was investigated using the HRM method. Efficacy of the HRM method in mutation detection was determined in comparison with direct sequencing. RESULTS: N-RAS mutations were detected in 7 of the 50 samples (14%). Most of the mutations were found in codon 12 (57.14%), and 28.57% and 14.28% of mutations were in codons 61 and 13, respectively. There was no statistically significant association between patients' demographic data and HRM results. CONCLUSION: According to mutation detection results and the HRM results confirmation with the sequencing method, this method can be introduced as an efficient, low-cost, and fast method for detecting common mutations.


Assuntos
Análise Mutacional de DNA/métodos , Genes ras/genética , Leucemia Mieloide Aguda/genética , Desnaturação de Ácido Nucleico , Adulto , Códon , Feminino , Humanos , Leucemia Mieloide Aguda/sangue , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Mutação
11.
Asia Pac J Clin Oncol ; 18(5): e363-e368, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35073441

RESUMO

BACKGROUND: RAS mutation testing now routinely informs the optimal management of metastatic colorectal cancer (mCRC), specifically the finding of a RAS mutation defines patients who will not benefit from treatment with an epidermal growth factor receptor inhibitor. Over time more RAS genes have been tested and more sensitive techniques used. AIMS: To review routine care RAS testing and results over time. METHODS: A retrospective analysis of the molecular data collected prospectively in the multi-site Treatment of Recurrent and Advanced Colorectal Cancer (TRACC) registry from 2009 to 2018 was undertaken. Patients with RAS data were further analyzed. In parallel, the RAS mutation status of patients enrolled in the Test Tailor Treat (TTT) program was examined for 2011-2018. RESULTS: Of 2908 patients in the TRACC registry, 1892 (65%) were tested, with 898 (47%) of tested patients found to be RAS mutant (RASmt). RAS data were available for 5935 TTT patients. Of the tested TRACC patients diagnosed in 2009 and 2010, 38% were RASmt. For each 2-year period from 2011/2012 through to 2017/2018, the prevalence of RASmt in TRACC and TTT was 42% and 40% (2011/2012), 52% and 40% (2013/2014), 47% and 49% (2015/2016), and 47% and 49% (2017/2018). CONCLUSIONS: Based on both TRACC and TTT data, the proportion of patients reported to have a RAS mutation increased from 2009 to 2015 but has remained relatively stable in recent years. The increased proportion of RASmt patients observed over time is likely largely driven by the uptake of extended RAS testing.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Austrália , Neoplasias do Colo/genética , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Genes ras/genética , Humanos , Mutação , Recidiva Local de Neoplasia , Estudos Retrospectivos
12.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 39(11): 825-830, 2021 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-34886641

RESUMO

Objective: To explore the effects of K-ras gene on the expressions of oncogenes and cancer suppressor genes in human bronchial epithelial (HBE) cells which were exposed to PM(2.5). Methods: According to the mRNA sequence of K-ras gene provided by GenBank in September 2019, interference sequences were designed and synthesized, and the recombinant lentiviral vector was transfected into HBE cell to construct the K-ras gene-silenced cells. HBE cells and K-ras gene-silenced cells were exposed to 10 µg/ml, 50 µg/ml PM(2.5) suspension and 10 µmol/L Cr(6+). Real-time fluorescent quantitative PCR was used to detect the mRNA expression levels of c-myc, c-fos, N-ras, cyclin-D1, p16 and p53 genes, the expression levels of p53 and c-myc proteins were detected by Western blot. Results: In K-ras silenced cell group, K-ras mRNA expression level decreased (80.5%±3.6%) and K-ras protein level decreased (58.9%±4.7%) when compared with the control group (P<0.01) . Compared with the correspoding cell control group without exposure, the mRNA expression levels of c-myc, c-fos, N-ras and cyclin-D1 genes in HBE cell group exposed to different concentrations of PM(2.5), K-ras silenced cell group exposed to different concentrations of PM(2.5), HBE cell group exposed to 10 µmol/L Cr(6+) and K-ras silenced cell group exposed to 10 µmol/L Cr(6+) were increased, the mRNA expressions of p16 and p53 genes were decreased (P<0.01) . Compared with HBE cell group exposed to 10 µg/ml PM(2.5), the mRNA expressions of c-myc, c-fos and p16 genes in K-ras silenced cells exposed to 10 µg/ml PM(2.5) were decreased, and the p53 mRNA level was increased (P<0.01) . Compared with HBE cell group exposed to 50 µg/ml PM(2.5), the mRNA expression levels of c-fos, N-ras, cyclin-D1, p16 and p53 genes in K-ras silenced cell group exposed to 50 µg/ml PM(2.5) were decreased (P<0.01) . Compared with the HBE cell group without exposure, c-myc protein increased and p53 protein decreased in HBE cells exposed to 50 µg/ml PM(2.5) (P<0.05) . Compared with the K-ras silenced cell group without exposure, c-myc protein increased in K-ras silenced cells exposed to 50 µg/ml PM(2.5) (P<0.05) . Conclusion: PM(2.5) can increase the expression levels of oncogenes in HBE cells, and K-ras gene silencing can inhibit the expression levels of oncogenes in HBE cells treated with PM(2.5).


Assuntos
Genes ras , Oncogenes , Células Epiteliais , Genes ras/genética , Humanos , Material Particulado/toxicidade , Proteínas Proto-Oncogênicas c-fos/genética
14.
BMC Cancer ; 21(1): 1089, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34625038

RESUMO

BACKGROUND: Genetic alterations are common in non-small cell lung cancer (NSCLC), and DNA mutations and translocations are targets for therapy. Copy number aberrations occur frequently in NSCLC tumors and may influence gene expression and further alter signaling pathways. In this study we aimed to characterize the genomic architecture of NSCLC tumors and to identify genomic differences between tumors stratified by histology and mutation status. Furthermore, we sought to integrate DNA copy number data with mRNA expression to find genes with expression putatively regulated by copy number aberrations and the oncogenic pathways associated with these affected genes. METHODS: Copy number data were obtained from 190 resected early-stage NSCLC tumors and gene expression data were available from 113 of the adenocarcinomas. Clinical and histopathological data were known, and EGFR-, KRAS- and TP53 mutation status was determined. Allele-specific copy number profiles were calculated using ASCAT, and regional copy number aberration were subsequently obtained and analyzed jointly with the gene expression data. RESULTS: The NSCLC tumors tissue displayed overall complex DNA copy number profiles with numerous recurrent aberrations. Despite histological differences, tissue samples from squamous cell carcinomas and adenocarcinomas had remarkably similar copy number patterns. The TP53-mutated lung adenocarcinomas displayed a highly aberrant genome, with significantly altered copy number profiles including gains, losses and focal complex events. The EGFR-mutant lung adenocarcinomas had specific arm-wise aberrations particularly at chromosome7p and 9q. A large number of genes displayed correlation between copy number and expression level, and the PI(3)K-mTOR pathway was highly enriched for such genes. CONCLUSIONS: The genomic architecture in NSCLC tumors is complex, and particularly TP53-mutated lung adenocarcinomas displayed highly aberrant copy number profiles. We suggest to always include TP53-mutation status when studying copy number aberrations in NSCLC tumors. Copy number may further impact gene expression and alter cellular signaling pathways.


Assuntos
Adenocarcinoma de Pulmão/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Dosagem de Genes , Genes p53 , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/patologia , Alelos , Carcinoma Pulmonar de Células não Pequenas/patologia , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 9 , Classe I de Fosfatidilinositol 3-Quinases/genética , Variações do Número de Cópias de DNA , Ex-Fumantes , Feminino , Expressão Gênica , Genes erbB-1/genética , Genes ras/genética , Humanos , Neoplasias Pulmonares/patologia , Masculino , não Fumantes , Polimorfismo de Nucleotídeo Único , Transdução de Sinais/genética , Fumantes , Serina-Treonina Quinases TOR/genética
15.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34475208

RESUMO

In human neurodegenerative diseases, neurons can transfer toxic protein aggregates to surrounding cells, promoting pathology via poorly understood mechanisms. In Caenorhabditis elegans, proteostressed neurons can expel neurotoxic proteins in large, membrane-bound vesicles called exophers. We investigated how specific stresses impact neuronal trash expulsion to show that neuronal exopher production can be markedly elevated by oxidative and osmotic stress. Unexpectedly, we also found that fasting dramatically increases exophergenesis. Mechanistic dissection focused on identifying nonautonomous factors that sense and activate the fasting-induced exopher response revealed that DAF16/FOXO-dependent and -independent processes are engaged. Fasting-induced exopher elevation requires the intestinal peptide transporter PEPT-1, lipid synthesis transcription factors Mediator complex MDT-15 and SBP-1/SREPB1, and fatty acid synthase FASN-1, implicating remotely initiated lipid signaling in neuronal trash elimination. A conserved fibroblast growth factor (FGF)/RAS/MAPK signaling pathway that acts downstream of, or in parallel to, lipid signaling also promotes fasting-induced neuronal exopher elevation. A germline-based epidermal growth factor (EGF) signal that acts through neurons is also required for exopher production. Our data define a nonautonomous network that links food availability changes to remote, and extreme, neuronal homeostasis responses relevant to aggregate transfer biology.


Assuntos
Lipogênese/fisiologia , Estresse Fisiológico/fisiologia , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Genes ras/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Oxirredução , Transdução de Sinais
16.
BMC Cancer ; 21(1): 1025, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525976

RESUMO

BACKGROUND: Mutations in driver genes such as IDH and BRAF have been identified in gliomas. Meanwhile, dysregulations in the p53, RB1, and MAPK and/or PI3K pathways are involved in the molecular pathogenesis of glioblastoma. RAS family genes activate MAPK through activation of RAF and PI3K to promote cell proliferation. RAS mutations are a well-known driver of mutation in many types of cancers, but knowledge of their significance for glioma is insufficient. The purpose of this study was to reveal the frequency and the clinical phenotype of RAS mutant in gliomas. METHODS: This study analysed RAS mutations and their clinical significance in 242 gliomas that were stored as unfixed or cryopreserved specimens removed at Kyoto University and Osaka National Hospital between May 2006 and October 2017. The hot spots mutation of IDH1/2, H3F3A, HIST1H3B, and TERT promoter and exon 2 and exon 3 of KRAS, HRAS, and NRAS were analysed with Sanger sequencing method, and 1p/19q codeletion was analysed with multiplex ligation-dependent probe amplification. DNA methylation array was performed in some RAS mutant tumours to improve accuracy of diagnosis. RESULTS: RAS mutations were identified in four gliomas with three KRAS mutations and one NRAS mutation in one anaplastic oligodendroglioma, two anaplastic astrocytomas (IDH wild-type in each), and one ganglioglioma. RAS-mutant gliomas were identified with various types of glioma histology. CONCLUSION: RAS mutation appears infrequent, and it is not associated with any specific histological phenotype of glioma.


Assuntos
Neoplasias Encefálicas/genética , Genes ras/genética , Glioma/genética , Mutação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/genética , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Metilação de DNA , Metilases de Modificação do DNA/metabolismo , Análise Mutacional de DNA/métodos , Enzimas Reparadoras do DNA/metabolismo , Éxons/genética , Feminino , Glioblastoma/genética , Glioma/patologia , Histonas/genética , Humanos , Isocitrato Desidrogenase/genética , Masculino , Pessoa de Meia-Idade , Oligodendroglioma/genética , Fenótipo , Regiões Promotoras Genéticas , Telomerase/genética , Proteínas Supressoras de Tumor/metabolismo , Adulto Jovem
17.
Cancer Med ; 10(20): 6998-7011, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34535965

RESUMO

Despite reports on poor survival outcomes after hepatectomy for colorectal liver metastases (CRLM) with BRAF V600E mutation (mBRAF) exist, the role of mBRAF testing for technically resectable cases remains unclear. A single-center retrospective study was performed to investigate the survival outcomes of patients who underwent upfront hepatectomy for solitary resectable CRLM with mBRAF between January 2005 and December 2017 and to compare them with those of unresectable cases with mBRAF. Of 172 patients who underwent initial hepatectomy for solitary resectable CRLM, mBRAF, RAS mutations (mRAS), and wild-type RAS/BRAF (wtRAS/BRAF) were observed in 5 (2.9%), 73 (42.4%), and 93 (54.7%) patients, respectively. With a median follow-up period of 72.8 months, mBRAF was associated with a significantly shorter OS (median, 14.4 months) than wtRAS/BRAF (median, not reached [NR]) (hazard ratio [HR], 27.6; p < 0.001) and mRAS (median, NR) (HR, 9.9; p < 0.001), and mBRAF had the highest HR among all the indicators in the multivariable analysis (HR, 17.0; p < 0.001). The median OS after upfront hepatectomy for CRLM with mBRAF was identical to that of 28 unresectable CRLM with mBRAF that were treated with systemic chemotherapy (median, 17.2 months) (HR, 0.78; p = 0.65). When technically resectable CRLM are complicated with mBRAF, its survival outcome becomes as poor as unresectable cases; therefore, those with mBRAF should be considered as oncologically unresectable. Patients with CRLM should undergo pre-treatment mBRAF testing regardless of technical resectability. Clinical trial registration number: UMIN000034557.


Assuntos
Neoplasias Colorretais/genética , Genes ras/genética , Hepatectomia/mortalidade , Neoplasias Hepáticas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Códon , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Modelos de Riscos Proporcionais , Estudos Retrospectivos
18.
Genes (Basel) ; 12(7)2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34356110

RESUMO

Ras proteins are essential mediators of a multitude of cellular processes, and its deregulation is frequently associated with cancer appearance, progression, and metastasis. Ras-driven cancers are usually aggressive and difficult to treat. Although the recent Food and Drug Administration (FDA) approval of the first Ras G12C inhibitor is an important milestone, only a small percentage of patients will benefit from it. A better understanding of the context in which Ras operates in different tumor types and the outcomes mediated by each effector pathway may help to identify additional strategies and targets to treat Ras-driven tumors. Evidence emerging in recent years suggests that both oncogenic Ras signaling in tumor cells and non-oncogenic Ras signaling in stromal cells play an essential role in cancer. PI3K is one of the main Ras effectors, regulating important cellular processes such as cell viability or resistance to therapy or angiogenesis upon oncogenic Ras activation. In this review, we will summarize recent advances in the understanding of Ras-dependent activation of PI3K both in physiological conditions and cancer, with a focus on how this signaling pathway contributes to the formation of a tumor stroma that promotes tumor cell proliferation, migration, and spread.


Assuntos
Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas ras/genética , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Genes ras/genética , Humanos , Mutação , Neoplasias/genética , Neoplasias/metabolismo , Transdução de Sinais/genética , Proteínas ras/metabolismo
19.
PLoS Genet ; 17(8): e1009738, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34411095

RESUMO

Activation of Ras signaling occurs in ~30% of human cancers. However, activated Ras alone is insufficient to produce malignancy. Thus, it is imperative to identify those genes cooperating with activated Ras in driving tumoral growth. In this work, we have identified a novel EGFR inhibitor, which we have named EGFRAP, for EGFR adaptor protein. Elimination of EGFRAP potentiates activated Ras-induced overgrowth in the Drosophila wing imaginal disc. We show that EGFRAP interacts physically with the phosphorylated form of EGFR via its SH2 domain. EGFRAP is expressed at high levels in regions of maximal EGFR/Ras pathway activity, such as at the presumptive wing margin. In addition, EGFRAP expression is up-regulated in conditions of oncogenic EGFR/Ras activation. Normal and oncogenic EGFR/Ras-mediated upregulation of EGRAP levels depend on the Notch pathway. We also find that elimination of EGFRAP does not affect overall organogenesis or viability. However, simultaneous downregulation of EGFRAP and its ortholog PVRAP results in defects associated with increased EGFR function. Based on these results, we propose that EGFRAP is a new negative regulator of the EGFR/Ras pathway, which, while being required redundantly for normal morphogenesis, behaves as an important modulator of EGFR/Ras-driven tissue hyperplasia. We suggest that the ability of EGFRAP to functionally inhibit the EGFR pathway in oncogenic cells results from the activation of a feedback loop leading to increase EGFRAP expression. This could act as a surveillance mechanism to prevent excessive EGFR activity and uncontrolled cell growth.


Assuntos
Receptores ErbB/antagonistas & inibidores , Genes ras/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Ciclo Celular , Proliferação de Células/genética , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes ras/fisiologia , Discos Imaginais/metabolismo , Morfogênese , Fosforilação , Receptores de Peptídeos de Invertebrados/antagonistas & inibidores , Receptores de Peptídeos de Invertebrados/genética , Receptores de Peptídeos de Invertebrados/metabolismo , Transdução de Sinais/genética , Proteínas ras/genética
20.
Nat Commun ; 12(1): 4841, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404770

RESUMO

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


Assuntos
Senescência Celular/genética , Genes ras/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Carcinogênese , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Transformação Celular Neoplásica , Replicação do DNA , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Genômica , Células HeLa , Humanos , Oncogenes , Fenótipo , Fosfoproteínas , Fosforilação , Repressão Psicológica , Transdução de Sinais , Proteínas ras/genética
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