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1.
Nature ; 565(7741): 654-658, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30675060

RESUMO

Diffuse gliomas are the most common malignant brain tumours in adults and include glioblastomas and World Health Organization (WHO) grade II and grade III tumours (sometimes referred to as lower-grade gliomas). Genetic tumour profiling is used to classify disease and guide therapy1,2, but involves brain surgery for tissue collection; repeated tumour biopsies may be necessary for accurate genotyping over the course of the disease3-10. While the detection of circulating tumour DNA (ctDNA) in the blood of patients with primary brain tumours remains challenging11,12, sequencing of ctDNA from the cerebrospinal fluid (CSF) may provide an alternative way to genotype gliomas with lower morbidity and cost13,14. We therefore evaluated the representation of the glioma genome in CSF from 85 patients with gliomas who underwent a lumbar puncture because they showed neurological signs or symptoms. Here we show that tumour-derived DNA was detected in CSF from 42 out of 85 patients (49.4%) and was associated with disease burden and adverse outcome. The genomic landscape of glioma in the CSF included a broad spectrum of genetic alterations and closely resembled the genomes of tumour biopsies. Alterations that occur early during tumorigenesis, such as co-deletion of chromosome arms 1p and 19q (1p/19q codeletion) and mutations in the metabolic genes isocitrate dehydrogenase 1 (IDH1) or IDH21,2, were shared in all matched ctDNA-positive CSF-tumour pairs, whereas growth factor receptor signalling pathways showed considerable evolution. The ability to monitor the evolution of the glioma genome through a minimally invasive technique could advance the clinical development and use of genotype-directed therapies for glioma, one of the most aggressive human cancers.


Assuntos
Evolução Molecular , Glioma/líquido cefalorraquidiano , Glioma/genética , Biópsia Líquida , Mutação , Genes Neoplásicos/genética , Genoma Humano/genética , Genômica , Glioblastoma/líquido cefalorraquidiano , Glioblastoma/genética , Glioblastoma/patologia , Glioma/patologia , Humanos , Gradação de Tumores
2.
PLoS Comput Biol ; 16(7): e1007909, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32667922

RESUMO

Cancer cells have genetic alterations that often directly affect intracellular protein signaling processes allowing them to bypass control mechanisms for cell death, growth and division. Cancer drugs targeting these alterations often work initially, but resistance is common. Combinations of targeted drugs may overcome or prevent resistance, but their selection requires context-specific knowledge of signaling pathways including complex interactions such as feedback loops and crosstalk. To infer quantitative pathway models, we collected a rich dataset on a melanoma cell line: Following perturbation with 54 drug combinations, we measured 124 (phospho-)protein levels and phenotypic response (cell growth, apoptosis) in a time series from 10 minutes to 67 hours. From these data, we trained time-resolved mathematical models that capture molecular interactions and the coupling of molecular levels to cellular phenotype, which in turn reveal the main direct or indirect molecular responses to each drug. Systematic model simulations identified novel combinations of drugs predicted to reduce the survival of melanoma cells, with partial experimental verification. This particular application of perturbation biology demonstrates the potential impact of combining time-resolved data with modeling for the discovery of new combinations of cancer drugs.


Assuntos
Antineoplásicos/farmacologia , Melanoma , Fosfoproteínas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Modelos Biológicos , Fosfoproteínas/análise , Fosfoproteínas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Biologia de Sistemas
3.
J Am Soc Nephrol ; 26(4): 805-16, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25145934

RESUMO

TGF-ß(1) is a pleotropic growth factor that mediates glomerulosclerosis and podocyte apoptosis, hallmarks of glomerular diseases. The expression of microRNA-21 (miR-21) is regulated by TGF-ß(1), and miR-21 inhibits apoptosis in cancer cells. TGF-ß(1)-transgenic mice exhibit accelerated podocyte loss and glomerulosclerosis. We determined that miR-21 expression increases rapidly in cultured murine podocytes after exposure to TGF-ß(1) and is higher in kidneys of TGF-ß(1)-transgenic mice than wild-type mice. miR-21-deficient TGF-ß(1)-transgenic mice showed increased proteinuria and glomerular extracellular matrix deposition and fewer podocytes per glomerular tuft compared with miR-21 wild-type TGF-ß(1)-transgenic littermates. Similarly, miR-21 expression was increased in streptozotocin-induced diabetic mice, and loss of miR-21 in these mice was associated with increased albuminuria, podocyte depletion, and mesangial expansion. In cultured podocytes, inhibition of miR-21 was accompanied by increases in the rate of cell death, TGF-ß/Smad3-signaling activity, and expression of known proapoptotic miR-21 target genes p53, Pdcd4, Smad7, Tgfbr2, and Timp3. In American-Indian patients with diabetic nephropathy (n=48), albumin-to-creatinine ratio was positively associated with miR-21 expression in glomerular fractions (r=0.6; P<0.001) but not tubulointerstitial fractions (P=0.80). These findings suggest that miR-21 ameliorates TGF-ß(1) and hyperglycemia-induced glomerular injury through repression of proapoptotic signals, thereby inhibiting podocyte loss. This finding is in contrast to observations in murine models of tubulointerstitial kidney injury but consistent with findings in cancer models. The aggravation of glomerular disease in miR-21-deficient mice and the positive association with albumin-to-creatinine ratio in patients with diabetic nephropathy support miR-21 as a feedback inhibitor of TGF-ß signaling and functions.


Assuntos
Albuminúria/metabolismo , Nefropatias Diabéticas/metabolismo , Glomérulos Renais/metabolismo , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Adulto , Animais , Apoptose , Células Cultivadas , Matriz Extracelular/metabolismo , Feminino , Humanos , Glomérulos Renais/patologia , Masculino , Camundongos Endogâmicos DBA , Camundongos Knockout , Pessoa de Meia-Idade , Proteínas Smad/metabolismo
4.
Bioinformatics ; 30(14): 2051-9, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24665131

RESUMO

MOTIVATION: Somatic homozygous deletions of chromosomal regions in cancer, while not necessarily oncogenic, may lead to therapeutic vulnerabilities specific to cancer cells compared with normal cells. A recently reported example is the loss of one of the two isoenzymes in glioblastoma cancer cells such that the use of a specific inhibitor selectively inhibited growth of the cancer cells, which had become fully dependent on the second isoenzyme. We have now made use of the unprecedented conjunction of large-scale cancer genomics profiling of tumor samples in The Cancer Genome Atlas (TCGA) and of tumor-derived cell lines in the Cancer Cell Line Encyclopedia, as well as the availability of integrated pathway information systems, such as Pathway Commons, to systematically search for a comprehensive set of such epistatic vulnerabilities. RESULTS: Based on homozygous deletions affecting metabolic enzymes in 16 TCGA cancer studies and 972 cancer cell lines, we identified 4104 candidate metabolic vulnerabilities present in 1019 tumor samples and 482 cell lines. Up to 44% of these vulnerabilities can be targeted with at least one Food and Drug Administration-approved drug. We suggest focused experiments to test these vulnerabilities and clinical trials based on personalized genomic profiles of those that pass preclinical filters. We conclude that genomic profiling will in the future provide a promising basis for network pharmacology of epistatic vulnerabilities as a promising therapeutic strategy. AVAILABILITY AND IMPLEMENTATION: A web-based tool for exploring all vulnerabilities and their details is available at http://cbio.mskcc.org/cancergenomics/statius/ along with supplemental data files.


Assuntos
Genômica/métodos , Neoplasias/genética , Animais , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Deleção de Genes , Glioblastoma/genética , Humanos , Isoenzimas/genética , Camundongos , Neoplasias/tratamento farmacológico , Medicina de Precisão
5.
Blood ; 121(15): 2875-81, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23390194

RESUMO

Myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis that leads to peripheral cytopenias. We observed that SMAD7, a negative regulator of transforming growth factor-beta (TGF-ß) receptor-I kinase, is markedly reduced in MDS and leads to ineffective hematopoiesis by overactivation of TGF-ß signaling. To determine the cause of SMAD7 reduction in MDS, we analyzed the 3'UTR of the gene and determined that it contains a highly conserved putative binding site for microRNA-21. We observed significantly elevated levels of miR-21 in MDS marrow samples when compared with age-matched controls. miR-21 was shown to directly bind to the 3'UTR of SMAD7 and reduce its expression in hematopoietic cells. Next, we tested the role of miR-21 in regulating TGF-ß signaling in a TGF-ß-overexpressing transgenic mouse model that develops progressive anemia and dysplasia and thus serves as a model of human bone marrow failure. Treatment with a chemically modified miR-21 inhibitor led to significant increases in hematocrit and led to an increase in SMAD7 expression in vivo. Inhibition of miR-21 also led to an increase in erythroid colony formation from primary MDS bone marrow progenitors, demonstrating its ability in stimulating hematopoiesis in vitro. Taken together, these studies demonstrate the role of miR-21 in regulating overactivated TGF-ß signaling in MDS.


Assuntos
Hematopoese/genética , MicroRNAs/genética , Síndromes Mielodisplásicas/genética , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genética , Regiões 3' não Traduzidas/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Sítios de Ligação/genética , Células da Medula Óssea/metabolismo , Linhagem Celular , Células Cultivadas , Feminino , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Células K562 , Masculino , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Pessoa de Meia-Idade , Mutação , Síndromes Mielodisplásicas/metabolismo , Proteína Smad7/genética
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(3): 426-30, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26121867

RESUMO

OBJECTIVE: To observe the vestibular dysfunction in sudden sensorineural hearing loss (SSHL) patients without vertigo. METHODS: Forty-two cases of unilateral SSHL without vertigo were enrolled in the study from May 2012 to May 2014. All patients underwent air conducted sound elicited oVEMP and cVEMP respectively. Some of them also received caloric test. Sixty-two SSHL patients with vertigo and twenty-five age-and gender-matched normal subjects were recruited as controls to analyze the vestibular dysfunction in SSHL patients without. vertigo. RESULTS: Abnormal oVEMP was observed in 54. 8% affected ears without vertigo (23/42), 64. 5% ears with vertigo (40/62), and 26. 0% normal ears (13/50). Abnormal cVEMP was observed in 52. 4% affected ears without vertigo (22/42), 48. 4% ears with vertigo (30/62), and 14. 0% normal ears (7/50). Caloric test was operated in 21 SSHL patients without vertigo and 29 patients with vertigo. Abnormal caloric test was observed in 52.4% (11/21) SSHL patients without vertigo and 75. 9% (22/29) SSHL patients with vertigo respectively. Statistical significance was found in oVEMP and cVEMP rates between SSHL without vertigo and normal group (P<0. 01). However, no significant statistical difference was found in oVEMP, cVEMP rates and caloric test between SSHL without vertigo and SSHL with vertigo group (P>0. 05). CONCLUSION: Vestibular function could be damaged in SSHL patients without vertigo. The abnormal rates of oVEMP, cVEMP and caloric test in SSHL patients without vertigo were similar to that of SSHL patients with vertigo. The appearance of vertigo might be irrelevant to the range and extent of vestibular dysfunction.


Assuntos
Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/fisiopatologia , Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto/fisiopatologia , Testes Calóricos , Humanos , Som , Vertigem , Doenças Vestibulares/fisiopatologia , Testes de Função Vestibular
7.
Bioinformatics ; 29(16): 2071-2, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23766416

RESUMO

MOTIVATION: The interaction between drugs and their targets, often proteins, and between antibodies and their targets, is important for planning and analyzing investigational and therapeutic interventions in many biological systems. Although drug-target and antibody-target datasets are available in separate databases, they are not publicly available in an integrated bioinformatics resource. As medical therapeutics, especially in cancer, increasingly uses targeted drugs and measures their effects on biomolecular profiles, there is an unmet need for a user-friendly toolset that allows researchers to comprehensively and conveniently access and query information about drugs, antibodies and their targets. SUMMARY: The PiHelper framework integrates human drug-target and antibody-target associations from publicly available resources to help meet the needs of researchers in systems pharmacology, perturbation biology and proteomics. PiHelper has utilities to (i) import drug- and antibody-target information; (ii) search the associations either programmatically or through a web user interface (UI); (iii) visualize the data interactively in a network; and (iv) export relationships for use in publications or other analysis tools. AVAILABILITY: PiHelper is a free software under the GNU Lesser General Public License (LGPL) v3.0. Source code and documentation are at http://bit.ly/pihelper. We plan to coordinate contributions from the community by managing future releases.


Assuntos
Anticorpos , Descoberta de Drogas , Software , Bases de Dados Factuais , Internet , Proteômica
8.
PLoS Comput Biol ; 9(12): e1003290, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367245

RESUMO

We present a powerful experimental-computational technology for inferring network models that predict the response of cells to perturbations, and that may be useful in the design of combinatorial therapy against cancer. The experiments are systematic series of perturbations of cancer cell lines by targeted drugs, singly or in combination. The response to perturbation is quantified in terms of relative changes in the measured levels of proteins, phospho-proteins and cellular phenotypes such as viability. Computational network models are derived de novo, i.e., without prior knowledge of signaling pathways, and are based on simple non-linear differential equations. The prohibitively large solution space of all possible network models is explored efficiently using a probabilistic algorithm, Belief Propagation (BP), which is three orders of magnitude faster than standard Monte Carlo methods. Explicit executable models are derived for a set of perturbation experiments in SKMEL-133 melanoma cell lines, which are resistant to the therapeutically important inhibitor of RAF kinase. The resulting network models reproduce and extend known pathway biology. They empower potential discoveries of new molecular interactions and predict efficacious novel drug perturbations, such as the inhibition of PLK1, which is verified experimentally. This technology is suitable for application to larger systems in diverse areas of molecular biology.


Assuntos
Modelos Biológicos , Transdução de Sinais , Biologia de Sistemas , Linhagem Celular Tumoral , Humanos , Método de Monte Carlo , Probabilidade
9.
Am J Pathol ; 181(1): 334-46, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22609345

RESUMO

Prostaglandin transporter (PGT) mediates prostaglandin (PG) catabolism and PG signal termination. The prostanoid PGE(2), which induces angiogenesis and vasodilation, is diminished in diabetic skin, suggesting that PGT up-regulation could be important in wound healing deficiency, typified by diabetic foot ulcer. We hypothesized that up-regulation of PGT in hyperglycemia could contribute to weakened PGE(2) signaling, leading to impaired angiogenesis and wound healing. In human dermal microvascular endothelial cells (HDMECs), exposure to hyperglycemia increased PGT expression and activity up to threefold, accompanied by reduced levels of PGE(2). Hyperglycemia reduced HDMEC migration by 50% and abolished tube formation. Deficits in PGE(2) expression, HDMEC migration, and tube formation could be corrected by treatment with the PGT inhibitor T26A, consistent with the idea that PGT hyperactivity is responsible for impairments in angiogenesis mediated by PG signaling. In vivo, PGT expression was profoundly induced in diabetes and by wounding, correlating with diminished levels of proangiogenic factors PGE(2) and VEGF in cutaneous wounds of diabetic mice. Pharmacological inhibition of PGT corrected these deficits. PGT inhibition shortened cutaneous wound closure time in diabetic mice from 22 to 16 days. This effect was associated with increased proliferation, re-epithelialization, neovascularization, and blood flow. These data provide evidence that hyperglycemia enhances PGT expression and activity, leading to diminished angiogenic signaling, a possible key mechanism underlying defective wound healing in diabetes.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Neovascularização Patológica/fisiopatologia , Transportadores de Ânions Orgânicos/fisiologia , Pele/irrigação sanguínea , Cicatrização/fisiologia , Animais , Movimento Celular/fisiologia , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Dinoprostona/metabolismo , Endotélio Vascular/metabolismo , Células Epiteliais/fisiologia , Humanos , Hiperglicemia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Transportadores de Ânions Orgânicos/metabolismo , Fluxo Sanguíneo Regional/fisiologia , Pele/lesões , Pele/metabolismo , Regulação para Cima/fisiologia , Fator A de Crescimento do Endotélio Vascular/biossíntese
10.
Cancer Med ; 12(3): 2345-2355, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35906821

RESUMO

BACKGROUND: Genetic testing is recommended for all pancreatic ductal adenocarcinoma (PDAC) patients. Prior research demonstrates that multidisciplinary pancreatic cancer clinics (MDPCs) improve treatment- and survival-related outcomes for PDAC patients. However, limited information exists regarding the utility of integrated genetics in the MDPC setting. We hypothesized that incorporating genetics in an MDPC serving both PDAC patients and high-risk individuals (HRI) could: (1) improve compliance with guideline-based genetic testing for PDAC patients, and (2) optimize HRI identification and PDAC surveillance participation to improve early detection and survival. METHODS: Demographics, genetic testing results, and pedigrees were reviewed for PDAC patients and HRI at one institution over 45 months. Genetic testing analyzed 16 PDAC-associated genes at minimum. RESULTS: Overall, 969 MDPC subjects were evaluated during the study period; another 56 PDAC patients were seen outside the MDPC. Among 425 MDPC PDAC patients, 333 (78.4%) completed genetic testing; 29 (8.7%) carried a PDAC-related pathogenic germline variant (PGV). Additionally, 32 (9.6%) met familial pancreatic cancer (FPC) criteria. These PDAC patients had 191 relatives eligible for surveillance or genetic testing. Only 2/56 (3.6%) non-MDPC PDAC patients completed genetic testing (p < 0.01). Among 544 HRI, 253 (46.5%) had a known PGV or a designation of FPC, and were eligible for surveillance at baseline; of the remainder, 15/291 (5.2%) were eligible following genetic testing and PGV identification. CONCLUSION: Integrating genetics into the multidisciplinary setting significantly improved genetic testing compliance by reducing logistical barriers for PDAC patients, and clarified cancer risks for their relatives while conserving clinical resources. Overall, we identified 206 individuals newly eligible for surveillance or genetic testing (191 relatives of MDPC PDAC patients, and 15 HRI from this cohort), enabling continuity of care for PDAC patients and at-risk relatives in one clinic.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Predisposição Genética para Doença , Neoplasias Pancreáticas/patologia , Testes Genéticos , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas
11.
Nat Commun ; 14(1): 797, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781852

RESUMO

The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) is a complex ecosystem that drives tumor progression; however, in-depth single cell characterization of the PDAC TME and its role in response to therapy is lacking. Here, we perform single-cell RNA sequencing on freshly collected human PDAC samples either before or after chemotherapy. Overall, we find a heterogeneous mixture of basal and classical cancer cell subtypes, along with distinct cancer-associated fibroblast and macrophage subpopulations. Strikingly, classical and basal-like cancer cells exhibit similar transcriptional responses to chemotherapy and do not demonstrate a shift towards a basal-like transcriptional program among treated samples. We observe decreased ligand-receptor interactions in treated samples, particularly between TIGIT on CD8 + T cells and its receptor on cancer cells, and identify TIGIT as the major inhibitory checkpoint molecule of CD8 + T cells. Our results suggest that chemotherapy profoundly impacts the PDAC TME and may promote resistance to immunotherapy.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Microambiente Tumoral/genética , Ecossistema , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Análise de Sequência de RNA , Neoplasias Pancreáticas
12.
Zhongguo Zhen Jiu ; 42(6): 634-8, 2022 Jun 12.
Artigo em Zh | MEDLINE | ID: mdl-35712947

RESUMO

OBJECTIVE: To observe the clinical effect of acupuncture on coronavirus disease 2019 (COVID-19) based on the conventional treatment. METHODS: A total of 35 patients with COVID-19 of mild or ordinary type were involved (3 cases dropped off). Acupuncture was applied on the basis of western medicine and Chinese materia medica treatment. Dazhui (GV 14), Fengchi (GB 20), Kongzui (LU 6), Hegu (LI 4), etc. were selected as the main acupoints, the supplementary acupoints and the reinforcing and reducing manipulations were selected according to syndrome differentiation. Acupuncture treatment was given once a day, 5 times a week. On day 3 and day 7 of acupuncture, relief condition of the main symptoms was observed. Before acupuncture and on day 3 and day 7 of acupuncture, efficacy evaluation scale of TCM on COVID-19 (efficacy evaluation scale) score was recorded. The effects of different intervention time of acupuncture on patients' hospitalization time were compared, the understanding of acupuncture treatment of patients discharged from hospital was recorded, the clinical efficacy and safety of acupuncture treatment were evaluated. RESULTS: On day 3 and day 7 of acupuncture, the symptoms of lung system and non lung system were both relieved; the scores of efficacy evaluation scale were both decreased compared before acupuncture (P<0.05), and the efficacy evaluation scale score of day 7 of acupuncture were lower than day 3 of acupuncture (P<0.05). The average hospitalization time of patients received early acupuncture was shorter than late acupuncture (P<0.05). The total effective rate was 84.4% (27/32) on day 7 of acupuncture, which was higher than 34.4% (11/32) on day 3 of acupuncture (P<0.05). During the acupuncture treatment, there were neither adverse reactions in patients nor occupational exposures in doctors. The patients generally believed that acupuncture could promote the recovery of COVID-19 and recommended acupuncture treatment. CONCLUSION: On the basis of the conventional treatment, acupuncture can effectively relieve the clinical symptoms in patients with COVID-19, early intervention of acupuncture can accelerate the recovery process. Acupuncture has good safety, clinical compliance and recognition of patients.


Assuntos
Terapia por Acupuntura , COVID-19 , Pontos de Acupuntura , COVID-19/terapia , Terapia Combinada , Humanos , Resultado do Tratamento
13.
Nat Commun ; 13(1): 1450, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35304457

RESUMO

The efficacy of the highly selective RET inhibitor selpercatinib is now established in RET-driven cancers, and we sought to characterize the molecular determinants of response and resistance. We find that the pre-treatment genomic landscape does not shape the variability of treatment response except for rare instances of RAS-mediated primary resistance. By contrast, acquired selpercatinib resistance is driven by MAPK pathway reactivation by one of two distinct routes. In some patients, on- and off-target pathway reactivation via secondary RET solvent front mutations or MET amplifications are evident. In other patients, rare RET-wildtype tumor cell populations driven by an alternative mitogenic driver are selected for by treatment. Multiple distinct mechanisms are often observed in the same patient, suggesting polyclonal resistance may be common. Consequently, sequential RET-directed therapy may require combination treatment with inhibitors targeting alternative MAPK effectors, emphasizing the need for prospective characterization of selpercatinib-treated tumors at the time of monotherapy progression.


Assuntos
Neoplasias Pulmonares , Neoplasias da Glândula Tireoide , Humanos , Pulmão , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-ret/genética , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética
14.
Cancer Sci ; 102(7): 1287-92, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21443647

RESUMO

The isoquinoline plant alkaloid berberine has anti-tumor effects on a variety of carcinoma cells, mainly through inhibition of cell proliferation, apoptosis induction and cell cycle arrest. However, the mechanisms underlying its role in tumor progression are unknown. In the present study, we investigated the molecular mechanisms involved in berberine-induced cell death in human hepatoma carcinoma cell (HCC) lines HepG2 and SMMC7721. Our results showed that berberine inhibited tumor cell viability in a dose- and time-dependent manner, and induced cell death via apoptosis and autophagy. Moreover, berberine treatment significantly inhibited CD147 expression by HCC cells in a dose-dependent manner. Overexpression of CD147 protein markedly reduced berberine-induced cell death. Our data provide the first experimental evidence that berberine induces cell death in HCC cells via downregulation of CD147 and suggest a new mechanism to explain its anti-tumor effects.


Assuntos
Apoptose/efeitos dos fármacos , Basigina/fisiologia , Berberina/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Neoplasias Hepáticas/patologia
15.
Genome Med ; 13(1): 96, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059130

RESUMO

BACKGROUND: Cell-free DNA (cfDNA) profiling is increasingly used to guide cancer care, yet mutations are not always identified. The ability to detect somatic mutations in plasma depends on both assay sensitivity and the fraction of circulating DNA in plasma that is tumor-derived (i.e., cfDNA tumor fraction). We hypothesized that cfDNA tumor fraction could inform the interpretation of negative cfDNA results and guide the choice of subsequent assays of greater genomic breadth or depth. METHODS: Plasma samples collected from 118 metastatic cancer patients were analyzed with cf-IMPACT, a modified version of the FDA-authorized MSK-IMPACT tumor test that can detect genomic alterations in 410 cancer-associated genes. Shallow whole genome sequencing (sWGS) was also performed in the same samples to estimate cfDNA tumor fraction based on genome-wide copy number alterations using z-score statistics. Plasma samples with no somatic alterations detected by cf-IMPACT were triaged based on sWGS-estimated tumor fraction for analysis with either a less comprehensive but more sensitive assay (MSK-ACCESS) or broader whole exome sequencing (WES). RESULTS: cfDNA profiling using cf-IMPACT identified somatic mutations in 55/76 (72%) patients for whom MSK-IMPACT tumor profiling data were available. A significantly higher concordance of mutational profiles and tumor mutational burden (TMB) was observed between plasma and tumor profiling for plasma samples with a high tumor fraction (z-score≥5). In the 42 patients from whom tumor data was not available, cf-IMPACT identified mutations in 16/42 (38%). In total, cf-IMPACT analysis of plasma revealed mutations in 71/118 (60%) patients, with clinically actionable alterations identified in 30 (25%), including therapeutic targets of FDA-approved drugs. Of the 47 samples without alterations detected and low tumor fraction (z-score<5), 29 had sufficient material to be re-analyzed using a less comprehensive but more sensitive assay, MSK-ACCESS, which revealed somatic mutations in 14/29 (48%). Conversely, 5 patients without alterations detected by cf-IMPACT and with high tumor fraction (z-score≥5) were analyzed by WES, which identified mutational signatures and alterations in potential oncogenic drivers not covered by the cf-IMPACT panel. Overall, we identified mutations in 90/118 (76%) patients in the entire cohort using the three complementary plasma profiling approaches. CONCLUSIONS: cfDNA tumor fraction can inform the interpretation of negative cfDNA results and guide the selection of subsequent sequencing platforms that are most likely to identify clinically-relevant genomic alterations.


Assuntos
Biomarcadores Tumorais , DNA Tumoral Circulante , Biópsia Líquida/métodos , Neoplasias/diagnóstico , Neoplasias/genética , Variações do Número de Cópias de DNA , Genômica/métodos , Humanos , Mutação , Curva ROC , Sequenciamento do Exoma , Sequenciamento Completo do Genoma
16.
Nat Commun ; 12(1): 3770, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145282

RESUMO

Circulating cell-free DNA from blood plasma of cancer patients can be used to non-invasively interrogate somatic tumor alterations. Here we develop MSK-ACCESS (Memorial Sloan Kettering - Analysis of Circulating cfDNA to Examine Somatic Status), an NGS assay for detection of very low frequency somatic alterations in 129 genes. Analytical validation demonstrated 92% sensitivity in de-novo mutation calling down to 0.5% allele frequency and 99% for a priori mutation profiling. To evaluate the performance of MSK-ACCESS, we report results from 681 prospective blood samples that underwent clinical analysis to guide patient management. Somatic alterations are detected in 73% of the samples, 56% of which have clinically actionable alterations. The utilization of matched normal sequencing allows retention of somatic alterations while removing over 10,000 germline and clonal hematopoiesis variants. Our experience illustrates the importance of analyzing matched normal samples when interpreting cfDNA results and highlights the importance of cfDNA as a genomic profiling source for cancer patients.


Assuntos
Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Marcadores Genéticos/genética , Neoplasias/genética , Análise Mutacional de DNA/métodos , Frequência do Gene/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação/genética , Neoplasias/sangue , Neoplasias/patologia
17.
Aging (Albany NY) ; 12(7): 6385-6400, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32267831

RESUMO

Long noncoding RNAs (lncRNAs) play important roles in the development of vascular diseases. However, the effect of lncRNA NORAD on atherosclerosis remains unknown. This study aimed to investigate the effect NORAD on endothelial cell injury and atherosclerosis. Ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed ApoE-/- mice were used as in vitro and in vivo models. Results showed that NORAD-knockdown induced cell cycle arrest in G0/G1 phase, aggravated ox-LDL-induced cell viability reduction, cell apoptosis, and cell senescence along with the increased expression of Bax, P53, P21 and cleaved caspase-3 and the decreased expression of Bcl-2. The effect of NORAD on cell viability was further verified via NORAD-overexpression. NORAD- knockdown increased ox-LDL-induced reactive oxygen species, malondialdehyde, p-IKBα expression levels and NF-κB nuclear translocation. Proinflammatory molecules ICAM, VCAM, and IL-8 were also increased by NORAD- knockdown. Additionally, we identified the strong interaction of NORAD and IL-8 transcription repressor SFPQ in HUVECs. In ApoE-/- mice, NORAD-knockdown increased the lipid disorder and atherosclerotic lesions. The results have suggested that lncRNA NORAD attenuates endothelial cell senescence, endothelial cell apoptosis, and atherosclerosis via NF-κB and p53-p21 signaling pathways and IL-8, in which NORAD-mediated effect on IL-8 might through the direct interaction with SFPQ.


Assuntos
Aterosclerose/genética , Células Endoteliais/metabolismo , Interleucina-8/metabolismo , Lipoproteínas LDL/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Apoptose , Pontos de Checagem do Ciclo Celular , Senescência Celular , Regulação para Baixo , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , NF-kappa B/metabolismo , Oxirredução , Transdução de Sinais
18.
Cancer Med ; 9(17): 6093-6101, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32633890

RESUMO

PURPOSE: The enucleation rate for retinoblastoma has dropped from over 95% to under 10% in the past 10 years as a result of improvements in therapy. This reduces access to tumor tissue for molecular profiling, especially in unilateral retinoblastoma, and hinders the confirmation of somatic RB1 mutations necessary for genetic counseling. Plasma cell-free DNA (cfDNA) has provided a platform for noninvasive molecular profiling in cancer, but its applicability in low tumor burden retinoblastoma has not been shown. We analyzed cfDNA collected from 10 patients with available tumor tissue to determine whether sufficient tumorderived cfDNA is shed in plasma from retinoblastoma tumors to enable noninvasive RB1 mutation detection. METHODS: Tumor tissue was collected from eye enucleations in 10 patients diagnosed with advanced intra-ocular unilateral retinoblastoma, three of which went on to develop metastatic disease. Tumor RB1 mutation status was determined using an FDA-cleared tumor sequencing assay, MSK-IMPACT. Plasma samples were collected before eye enucleation and analyzed with a customized panel targeting all exons of RB1. RESULTS: Tumor-guided genotyping detected 10 of the 13 expected somatic RB1 mutations in plasma cfDNA in 8 of 10 patients (average variant allele frequency 3.78%). Without referring to RB1 status in the tumor, de novo mutation calling identified 7 of the 13 expected RB1 mutations (in 6 of 10 patients) with high confidence. CONCLUSION: Plasma cfDNA can detect somatic RB1 mutations in patients with unilateral retinoblastoma. Since intraocular biopsies are avoided in these patients because of concern about spreading tumor, cfDNA can potentially offer a noninvasive platform to guide clinical decisions about treatment, follow-up schemes, and risk of metastasis.


Assuntos
DNA Tumoral Circulante/genética , Genes do Retinoblastoma/genética , Neoplasias da Retina/genética , Retinoblastoma/genética , Institutos de Câncer , Pré-Escolar , DNA Tumoral Circulante/sangue , Análise Mutacional de DNA/métodos , Éxons/genética , Enucleação Ocular , Estudos de Viabilidade , Técnicas de Genotipagem , Humanos , Lactente , Recém-Nascido , Cidade de Nova Iorque , Neoplasias da Retina/sangue , Neoplasias da Retina/terapia , Retinoblastoma/sangue , Retinoblastoma/terapia
20.
Mech Dev ; 123(5): 388-94, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16701984

RESUMO

Precise regulation of the signaling range of secreted molecules is essential for proper pattern formation during development. The Nodal family of TGF-beta proteins has been shown to function as both short- and long-range signals. But the underlying mechanisms remain elusive. In this study, we investigated the regulation of the signaling range of zebrafish Nodal proteins Cyclops and Squint, which are short- and long-range signals, respectively. We show that (1) the stability of Cyclops and Squint correlates with the activity range but increasing the stability of the short-range Cyclops does not increase its signaling range; (2) structural differences in the N-terminus region of the mature peptides of Cyclops and Squint determine their differences in the signaling range and swapping the N-terminus region of the Squint mature ligand into that of Cyclops makes the latter function at a distance.


Assuntos
Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Padronização Corporal , Embrião não Mamífero , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Fatores de Determinação Direita-Esquerda , Dados de Sequência Molecular , Ligantes da Sinalização Nodal , Estrutura Terciária de Proteína , Fator de Crescimento Transformador beta/genética , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética
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