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A newborn presented with extensive rounded and velvety epidermal nevus (RAVEN) with a genetic study of the cutaneous lesions revealing a heterozygous mutation in FGFR2 (p.Cys382Arg). By 2 years of age, the patient developed hair heterochromia and autism spectrum disorder. Although RAVEN was initially associated with fibroblast growth factor 3 (FGFR3) mutations, three cases of RAVEN have been identified with mutations in FGFR2 (p.Ser252Trp) and one case of linear keratinocytic epidermal nevi has been identified with the same mutation as the mutation identified in our patient. This strongly supports the pathogenic role of these mutations.
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Transtorno do Espectro Autista , Transtorno Autístico , Corvos , Nevo Sebáceo de Jadassohn , Nevo , Recém-Nascido , Animais , Humanos , Nevo/patologia , Mutação , Cabelo/patologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genéticaRESUMO
BACKGROUND: Mismatch repair (MMR) deficiency is the hallmark of tumours from Lynch syndrome (LS), sporadic MLH1 hypermethylated and Lynch-like syndrome (LLS), but there is a lack of understanding of the variability in their mutational profiles based on clinical phenotypes. The aim of this study was to perform a molecular characterisation to identify novel features that can impact tumour behaviour and clinical management. METHODS: We tested 105 MMR-deficient colorectal cancer tumours (25 LS, 35 LLS and 45 sporadic) for global exome microsatellite instability, cancer mutational signatures, mutational spectrum and neoepitope load. RESULTS: Fifty-three percent of tumours showed high contribution of MMR-deficient mutational signatures, high level of global exome microsatellite instability, loss of MLH1/PMS2 protein expression and included sporadic tumours. Thirty-one percent of tumours showed weaker features of MMR deficiency, 62% lost MSH2/MSH6 expression and included 60% of LS and 44% of LLS tumours. Remarkably, 9% of all tumours lacked global exome microsatellite instability. Lastly, HLA-B07:02 could be triggering the neoantigen presentation in tumours that show the strongest contribution of MMR-deficient tumours. CONCLUSIONS: Next-generation sequencing approaches allow for a granular molecular characterisation of MMR-deficient tumours, which can be essential to properly diagnose and treat patients with these tumours in the setting of personalised medicine.
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Neoplasias Colorretais Hereditárias sem Polipose , Instabilidade de Microssatélites , Neoplasias Encefálicas , Neoplasias Colorretais , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Humanos , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Proteína 1 Homóloga a MutL/genética , Mutação , Síndromes Neoplásicas HereditáriasRESUMO
The most frequent cause of death by cancer worldwide is lung cancer, and the 5-year survival rate is still very poor for patients with advanced stage. Understanding the crosstalk between the signaling pathways that are involved in disease, especially in metastasis, is crucial to developing new targeted therapies. Toll-like receptors (TLRs) are master regulators of the immune responses, and their dysregulation in lung cancer is linked to immune escape and promotes tumor malignancy by facilitating angiogenesis and proliferation. On the other hand, over-activation of the WNT signaling pathway has been reported in lung cancer and is also associated with tumor metastasis via induction of Epithelial-to-mesenchymal-transition (EMT)-like processes. An interaction between both TLRs and the WNT pathway was discovered recently as it was found that the TLR pathway can be activated by WNT ligands in the tumor microenvironment; however, the implications of such interactions in the context of lung cancer have not been discussed yet. Here, we offer an overview of the interaction of TLR-WNT in the lung and its potential implications and role in the oncogenic process.
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Neoplasias Pulmonares , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Humanos , Imunidade , Imunomodulação , Neoplasias Pulmonares/metabolismo , Receptores Toll-Like/metabolismo , Microambiente Tumoral , Via de Sinalização WntRESUMO
Mantle Cell Lymphoma (MCL) is an aggressive lymphoma subtype that accounts for 6-8% of non-Hodgkin lymphomas. The disease is mostly incurable and characterized by a continuous pattern of relapse. Major changes have recently been implemented in the management of MCL, but continuous relapses still mark this disease as a challenge for clinicians. We previously reported the efficacy of GemOx-R (Gemcitabine, Oxaliplatin and Rituximab) in patients with refractory and relapsing MCL. We present results for a larger series with longer follow-up and including high-risk frontline patients, showing an overall response rate of 83%. The efficacy of each component of GemOx-R was evaluated in a panel of MCL cell lines. Also, patient-derived primary cells were used in ex vivo experiments. The results show that oxaliplatin has a profound effect on cellular viability and is the most effective drug within this regimen. We further present synergistic efficacy of oxaliplatin combined with cytarabine in MCL cells. Interestingly, this synergistic effect was not seen when cisplatin and cytarabine were combined, indicating that among the platinum-derived agents oxaliplatin may be the preferred approach. Taken together our findings suggest that oxaliplatin alone or combined with cytarabine could constitute an alternative backbone for MCL regimens.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Linfoma de Célula do Manto/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Humanos , Linfoma de Célula do Manto/diagnóstico , Linfoma de Célula do Manto/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Recidiva , Retratamento , Estudos Retrospectivos , Rituximab/administração & dosagem , Terapia de Salvação , Resultado do TratamentoRESUMO
MDM2 is a critical negative regulator of the p53 tumor suppressor protein. Selected sarcoma subtypes are being treated with Trabectedin in second line, which promotes DNA damage and p53-dependent apoptosis. The aim of this study was to evaluate the improvement of Trabectedin response with MDM2 inhibitors in soft tissue sarcomas. The antitumor effects of Trabectedin, Nutlin-3A and RG7112 as single agents or in combination were examined in vitro. RG7112 significantly synergized with Trabectedin in MDM2-amplified liposarcoma cells, representing a promising new therapeutic strategy for the treatment of sarcomas with MDM2 amplification.
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Antineoplásicos/farmacologia , Dioxóis/farmacologia , Imidazolinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Sarcoma/tratamento farmacológico , Sarcoma/metabolismo , Tetra-Hidroisoquinolinas/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Piperazinas/farmacologia , Trabectedina , Proteína Supressora de Tumor p53/metabolismoRESUMO
MDM2 is a critical negative regulator of the p53 tumor suppressor protein. Selected sarcoma subtypes are being treated with Trabectedin in second line, which promotes DNA damage and p53-dependent apoptosis. The aim of this study was to evaluate the improvement of Trabectedin response with MDM2 inhibitors in soft tissue sarcomas. The antitumor effects of Trabectedin, Nutlin-3A and RG7112 as single agents or in combination were examined in vitro. RG7112 significantly synergized with Trabectedin in MDM2-amplified liposarcoma cells, representing a promising new therapeutic strategy for the treatment of sarcomas with MDM2 amplification.
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The FOXO3 (Forkhead/winged helix box class O 3) transcription factor is a crucial regulator of haematopoietic cell fate that controls proliferation and apoptosis, among other processes. Despite the central role of FOXO3 as a tumour suppressor and phosphatidylinositol 3-kinase (PI3K)/AKT effector, little is known about its involvement in mantle cell lymphoma (MCL) biology. This study investigated the expression and activity of FOXO3 in MCL cell lines and in primary cultures. We analysed the expression of key FOXO regulators and targets, and studied the effect of modulators of FOXO function on cell viability and apoptosis. FOXO3 was constitutively inactivated in MCL cell lines, and showed cytoplasmic localization in patient-derived cells. PI3K and AKT, but not mammalian target of rapamycin (mTOR), inhibitors induced FOXO3 nuclear translocation and activation in correlation with their impact on MCL proliferation and survival. Moreover, FOXO3-defective cells were resistant to PI3K/AKT inhibitors. Reactivation of FOXO function with a nuclear export inhibitor had a profound effect on cell viability, consistent with FOXO3 nuclear accumulation. Interestingly, inhibition of FOXO3 nuclear export enhanced the effect of doxorubicin. Taken together, our results confirm that FOXO3 is a relevant regulator of proliferation and apoptosis in MCL, and suggest that reactivation of FOXO3 function might be a useful therapeutic strategy in MCL patients.
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Fatores de Transcrição Forkhead/fisiologia , Genes Supressores de Tumor , Linfoma de Célula do Manto/patologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/enzimologia , Doxorrubicina/farmacologia , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/antagonistas & inibidores , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma de Célula do Manto/genética , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transcrição Gênica , Tirosina/análogos & derivados , Tirosina/farmacologiaRESUMO
Notch has been linked to beta-catenin-dependent tumorigenesis; however, the mechanisms leading to Notch activation and the contribution of the Notch pathway to colorectal cancer is not yet understood. By microarray analysis, we have identified a group of genes downstream of Wnt/beta-catenin (down-regulated when blocking Wnt/beta-catenin) that are directly regulated by Notch (repressed by gamma-secretase inhibitors and up-regulated by active Notch1 in the absence of beta-catenin signaling). We demonstrate that Notch is downstream of Wnt in colorectal cancer cells through beta-catenin-mediated transcriptional activation of the Notch-ligand Jagged1. Consistently, expression of activated Notch1 partially reverts the effects of blocking Wnt/beta-catenin pathway in tumors implanted s.c. in nude mice. Crossing APC(Min/+) with Jagged1(+/Delta) mice is sufficient to significantly reduce the size of the polyps arising in the APC mutant background indicating that Notch is an essential modulator of tumorigenesis induced by nuclear beta-catenin. We show that this mechanism is operating in human tumors from Familial Adenomatous Polyposis patients. We conclude that Notch activation, accomplished by beta-catenin-mediated up-regulation of Jagged1, is required for tumorigenesis in the intestine. The Notch-specific genetic signature is sufficient to block differentiation and promote vasculogenesis in tumors whereas proliferation depends on both pathways.
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Proteínas de Ligação ao Cálcio/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Membrana/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , Alelos , Animais , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular , Núcleo Celular/metabolismo , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteína Jagged-1 , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Proteínas Serrate-Jagged , Fatores de Transcrição TCF/metabolismo , Transcrição Gênica/genética , beta Catenina/metabolismoRESUMO
Recent studies have suggested that APC loss alone may be insufficient to promote aberrant Wnt/beta-catenin signalling. Our aim was to comprehensively characterize Wnt signalling components in a set of APC-associated familial adenomatous polyposis (FAP) tumours. Sixty adenomas from six FAP patients with known pathogenic APC mutations were included. Somatic APC and KRAS mutations, beta-catenin immunostaining, and qRT-PCR of APC, MYC, AXIN2 and SFRP1 were analysed. Array-comparative genomic hybridization (aCGH) was also assessed in 26 FAP adenomas and 24 paired adenoma-carcinoma samples. A somatic APC alteration was present in 15 adenomas (LOH in 11 and four point mutations). KRAS mutations were detected in 10% of the cases. APC mRNA was overexpressed in adenomas. MYC and AXIN2 were also overexpressed, with significant intra-case heterogeneity. Increased cytoplasmic and/or nuclear beta-catenin staining was seen in 94% and 80% of the adenomas. beta-Catenin nuclear staining was strongly associated with MYC levels (p value 0.03) but not with KRAS mutations. Copy number aberrations were rare. However, the recurrent chromosome changes observed more frequently contained Wnt pathway genes (p value 0.012). Based on beta-catenin staining and Wnt pathway target genes alterations the Wnt pathway appears to be constitutively activated in all APC-FAP tumours, with alterations occurring both upstream and downstream of APC. Wnt aberrations are present at both the DNA and the RNA level. Somatic profiling of APC-FAP tumours provides new insights into the role of APC in tumourigenesis.
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Polipose Adenomatosa do Colo/genética , Genes APC , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Wnt/fisiologia , Proteínas ras/fisiologia , Polipose Adenomatosa do Colo/metabolismo , Proteína da Polipose Adenomatosa do Colo/biossíntese , Proteína da Polipose Adenomatosa do Colo/genética , Adulto , Núcleo Celular/metabolismo , Hibridização Genômica Comparativa , Feminino , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Perda de Heterozigosidade , Masculino , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Transdução de Sinais/fisiologia , Adulto Jovem , beta Catenina/metabolismo , Proteínas ras/genéticaRESUMO
Soft tissue sarcomas (STS) are a very heterogeneous group of rare tumors, comprising more than 50 different histological subtypes that originate from mesenchymal tissue. Despite their heterogeneity, chemotherapy based on doxorubicin (DXR) has been in use for forty years now and remains the standard first-line treatment for locally advanced unresectable or metastatic STS, although overall survival could not be improved by combination with other chemotherapeutics. In this sense, the development of new therapeutic approaches continues to be a largely unmatched goal. The WNT/ß-catenin signaling pathway is involved in various fundamental processes for embryogenic development, including the proliferation and differentiation of mesenchymal stem cells. Although the role of this pathway has been widely researched in neoplasms of epithelial origin, little is known about its relevance for mesenchymal neoplasms. This review covers the most important molecular alterations of the WNT signaling pathway in STS. The detection of these alterations and the understanding of their functional consequences for those pathways controlling sarcomagenesis development and progression are crucial to broaden the current knowledge about STS as well as to identify novel drug targets. In this regard, the current therapeutic options and drug candidates to modulate WNT signaling, which are usually classified by their interaction site upstream or downstream of ß-catenin, and their presumable clinical impact on STS are also discussed.
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Introduction: Precision medicine is already a reality in oncology, since biomarker-driven therapies have clearly improved patient survival. Furthermore, a new, minimally invasive strategy termed 'liquid biopsy' (LB) has revolutionized the field by allowing comprehensive cancer genomic profiling through the analysis of circulating tumor DNA (ctDNA). However, its detection requires extremely sensitive and efficient technologies. A powerful molecular tool based on the principle of 'divide and conquer' has emerged to solve this problem. Thus, digital PCR (dPCR) allows absolute and accurate quantification of target molecules.Areas covered: In this review we will discuss the fundamentals of dPCR and the most common approaches used for partition of samples and quantification. The advantages and limitations of dPCR will be mentioned in the context of LB in oncology.Expert opinion: In our opinion, dPCR has proven to be one of the most sensitive methods available for LB analysis, albeit some aspects such as its capacity of multiplexing and protocol standardization still require further improvements. Furthermore, the increasing sensitivities and lower costs of next generation sequencing (NGS) methods position dPCR as a confirmatory and complementary technique for NGS results which will likely prove to be very useful for treatment monitoring and assessing minimal residual disease.
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Biópsia Líquida/métodos , Reação em Cadeia da Polimerase , Humanos , Neoplasia Residual/diagnósticoRESUMO
Mantle cell lymphoma has been considered an incurable disease with current chemotherapy regimens. Recent intense chemoimmunotherapy induction regimens with or without consolidation with autologous stem cell transplantation procedures are showing a potential for cure in a sizable fraction of patients. Similarly, in the salvage setting, preliminary experience with non-myeloablative allogeneic transplant may cure some patients even after multiple therapeutic failures. However, the recent knowledge of the three basic biologic derangements that are integrated in the disease may change the therapeutic approach of the disease in the near future. In fact, new drugs that target more specifically the major molecular alterations of the disease are being progressively incorporated into the therapeutic armamentarium of the disease. In the near future, more individualized approaches that will take into account not only risk factors present at diagnosis but also biomarkers representative of the molecular alterations present in the disease are foreseen. In this review, we are going to discuss the current therapeutic approaches and the main new drugs that target more specifically the major molecular pathways alterations of the disease.
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Sistemas de Liberação de Medicamentos/métodos , Linfoma de Célula do Manto/tratamento farmacológico , Biomarcadores , Humanos , Linfoma de Célula do Manto/terapia , Fatores de RiscoRESUMO
Objectives: The main objectives of the study were (1) to set-up a droplet digital PCR (ddPCR) assay for the non-invasive detection of G719S EGFR mutation in NSCLC patients; (2) to determine the limits of detection of the ddPCR assay for G719S mutation and (3) to compare COBAS® and ddPCR System for G719S quantification in plasma. Materials and Methods: Blood samples were collected from 22 patients diagnosed with advanced NSCLC. Then, plasma ctDNA was extracted with the Qiagen Circulating Nucleic Acids kit and quantified by QuantiFluor® dsDNA System. The mutational study of EGFR was carried out by digital droplet PCR (ddPCR) with the QX200 Droplet Digital PCR System with specific probes and primers. Results: We observed the lowest percentage of G719S mutant allele could be detected in a wildtype background was 0.058%. In the specificity analysis, low levels of G719S mutation were detected in healthy volunteers with a peak of 21.65 mutant copies per milliliter of plasma and 6.35 MAFs. In those patients whose tissue biopsy was positive for G719S mutation, mutant alleles could also be detected in plasma using both ddPCR and COBAS® System. Finally, when mutational status was studied using both genotyping techniques, higher mutant copies/ml and higher mutant allele fraction (MAF) correlated with higher Semiquantitative Index obtained by COBAS®. Conclusions: Although tissue biopsies cannot be replaced due to the large amount of information they provide regarding tumor type and structure, liquid biopsy and ddPCR represents a new promising strategy for genetic analysis of tumors from plasma samples. In the present study, G719S mutation was detected in a highly sensitive manner, allowing its monitorization with a non-invasive technique.
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The Wnt signaling pathway is an important cellular mechanism for regulating differentiation processes as well as cell cycle events, and different inhibitors of this pathway, for example, PRI-724, are showing promising results in clinical trials for treatment of advanced pancreatic adenocarcinoma or ovarian cancer. Growing evidence suggests that Wnt signaling may also be crucial for tumorigenesis and progression of soft tissue sarcomas (STS), a malignant neoplasm with few therapeutic options at an advanced state. Our study with several STS cell lines and primary cultures shows that inhibition of Wnt/ß-catenin signaling with PRI-724 is able to suppress cell viability/proliferation and to increase cell death rates. TCF/ß-catenin-mediated transcriptional activity is decreased in treated cells, leading to downregulation of its target genes CCND1 and CDC25A. The latter was critical because its downregulation via siRNA was able to mimic the effect of PRI-724 on cell cycle arrest and cell death induction. An evaluation of NCBI/GenBank data confirmed that CDC25A mRNA is elevated in STS patients. Importantly, PRI-724 in combination with standard STS chemotherapeutics doxorubicin or trabectedin enhanced their antitumoral effect in a synergistic manner according to isobolographic analysis, suggesting that Wnt inhibition through PRI-724 could be a beneficial combination regime in patients with advanced STS.
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Soft tissue sarcomas (STS) are a rare group of mesenchymal solid tumors with heterogeneous genetic profiles and clinical features. Systemic chemotherapy is the backbone treatment for advanced STS; however, STS frequently acquire resistance to standard therapies, which highlights the need to improve treatments and identify novel therapeutic targets. Increases in the knowledge of the molecular pathways that drive sarcomas have brought to light different molecular alterations that cause tumor initiation and progression. These findings have triggered a breakthrough of targeted therapies that are being assessed in clinical trials. Cancer stem cells (CSCs) exhibit mesenchymal stem cell (MSC) features and represent a subpopulation of tumor cells that play an important role in tumor progression, chemotherapy resistance, recurrence and metastasis. In fact, CSCs phenotypes have been identified in sarcomas, allied to drug resistance and tumorigenesis. Herein, we will review the published evidence of CSCs in STS, discussing the molecular characteristic of CSCs, the commonly used isolation techniques and the new possibilities of targeting CSCs as a way to improve STS treatment and consequently patient outcome.
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Células-Tronco Neoplásicas/metabolismo , Sarcoma/fisiopatologia , Animais , Humanos , CamundongosRESUMO
MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression at the post-transcriptional level, and they have been described as being associated with tumor prognosis. Here, miRNA profiling was planned to explore new molecular prognostic biomarkers in localized intestinal high-risk GIST. Paraffin tumor blocks of 14 and 86 patients were used in the discovery and expansion sets, respectively. GeneChip miRNA v3.0 was employed to identify the miRNAs differentially expressed between relapsed and non-relapsed patient samples, which were validated in the expansion set, by qRT-PCR. RT2 Profiler PCR Array was used for the screening of let-7e targets. Expression levels were correlated with relapse-free survival and overall survival. In the discovery set, 39 miRNAs were significantly deregulated, let-7e and miR-550 being the most underexpressed and overexpressed miRNAs in the relapsed group, respectively. In the expansion set, the underexpression of let-7e or the overexpression of 4 of its target genes (ACVR1B, CASP3, COL3A1, and COL5A2) were statistically associated with worse relapse-free survival. The expression of let-7e and 4 of its target genes are potential prognostic biomarkers in high-risk localized intestinal GIST. The expression of these genes is a potential molecular tool useful for a more accurate prognosis in this subset of GIST patients.
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MET alterations may provide a potential biomarker to evaluate patients who will benefit from treatment with MET inhibitors. Therefore, the purpose of the present study is to investigate the utility of a liquid biopsy-based strategy to assess MET alterations in cancer patients. We analyzed MET amplification in circulating free DNA (cfDNA) from 174 patients with cancer and 49 healthy controls and demonstrated the accuracy of the analysis to detect its alteration in patients. Importantly, a significant correlation between cfDNA concentration and MET copy number (CN) in cancer patients (r = 0.57, p <10-10) was determined. Furthermore, we evaluated two approaches to detect the presence of MET on circulating tumor cells (CTCs), using the CellSearch® and Parsortix systems and monitored patients under anti-EGFR treatment (n = 30) combining both cfDNA and CTCs analyses. This follow-up provides evidence for the potential of MET CN assessment when patients develop resistance to anti-EGFR therapy and a significant association between the presence of CTCs MET+ and the Overall Survival (OS) in head and neck cancer patients (P = 0.05; HR = 6.66). In conclusion, we develop specific and noninvasive assays to monitor MET status in cfDNA/CTCs and demonstrate the utility of plasma MET CN determination as a biomarker for monitoring the appearance of resistance to anti-EGFR therapy.
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Ácidos Nucleicos Livres/sangue , Dosagem de Genes , Neoplasias/sangue , Neoplasias/genética , Células Neoplásicas Circulantes/metabolismo , Proteínas Proto-Oncogênicas c-met/sangue , Proteínas Proto-Oncogênicas c-met/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Feminino , Humanos , Biópsia Líquida , Masculino , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Estudos Prospectivos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Estudos RetrospectivosRESUMO
BACKGROUND & AIMS: We identified the APC N1026S variant of unknown malignant potential in the adenomatous polyposis coli (APC) gene in a Spanish attenuated familial adenomatous polyposis (AFAP) family. The variant was located in the first of the 4 highly conserved 15-amino acid (AA) repeats within the beta-catenin union domain. Our aim was to determine its functional relevance to establish its pathogenicity. METHODS: N1026S variant was analyzed in 22 members of the AFAP family studied, in 236 sporadic colorectal cancer cases, 203 matched controls, and 205 unrelated familial colorectal cancer cases. To assess its effects on beta-catenin binding, beta-catenin/Tcf-4-mediated transcription and beta-catenin subcellular distribution we performed affinity chromatography experiments, BIAcore 1000 (BIAcore AB, Uppsala, Sweden) assays, luciferase reporter assays, assessment of c-myc messenger RNA levels, and cell fractionation. RESULTS: N1026S variant cosegregated with the disease in the AFAP family studied. None of the sporadic or familial cases as well as the controls analyzed was positive for the variant. N1026S variant completely precluded beta-catenin binding to the first 15-AA repeat and diminished it when all four 15-AA repeats were present. Expression of APC N1026S in SW480 and DLD-1 cells did not diminish beta-catenin/Tcf-4-mediated transcription as effectively as APC wild-type. N1026S did not decrease c-myc transcription in DLD1 cells and nuclear beta-catenin in SW480 cells as effectively as WT. CONCLUSIONS: These findings strongly support a pathogenic role of the APC N1026S variant in the AFAP phenotype, reinforcing the importance of functional characterization of APC variants for genetic counseling.
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Polipose Adenomatosa do Colo/genética , Genes APC/fisiologia , Mutação em Linhagem Germinativa/fisiologia , Mutação de Sentido Incorreto/fisiologia , Polipose Adenomatosa do Colo/metabolismo , Polipose Adenomatosa do Colo/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , RNA Mensageiro/metabolismo , Espanha , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , beta Catenina/genética , beta Catenina/metabolismoRESUMO
Purpose: Nilotinib plus doxorubicin showed to be synergistic regarding apoptosis in several sarcoma cell lines. A phase I/II trial was thus designed to explore the feasibility of nilotinib as coadjuvant of doxorubicin by inhibiting MRP-1/P-gp efflux activity. The phase I part of the study is presented here.Patients and Methods: Nilotinib 400 mg/12 hours was administered in fixed dose from day 1 to 6, and doxorubicin on day 5 of each cycle. Three dose escalation levels for doxorubicin at 60, 65, and 75 mg/m2 were planned. Cycles were repeated every 3 weeks for a total of 4 cycles. Eligible subtypes were retroperitoneal liposarcoma, leiomyosarcoma, and unresectable/metastatic high-grade chondrosarcoma.Results: Thirteen patients were enrolled: 7 chondrosarcoma, 4 liposarcoma, and 2 leiomyosarcoma. In 46 cycles administered, the most relevant grade 3/4 adverse effects per patient were neutropenia 54%, febrile neutropenia 15%, and asthenia 8%. No cardiac toxicity was observed. Only one dose-limiting toxicity (febrile neutropenia) was reported in the third dose level. With regard to efficacy, 1 partial response (1 liposarcoma), 9 stable diseases (5 chondrosarcoma, 2 liposarcoma, 1 leiomyosarcoma), and 3 progressive diseases (2 chondrosarcoma and 1 leiomyosarcoma) were present. ABCB1 and ABCC1 RNA expression levels decreased by 58.47-fold and 1.47-fold, respectively, on day 5 of the cycle.Conclusions: Combination of MRP-1/P-gp inhibitor, nilotinib, as coadjuvant with doxorubicin is feasible; it appears not to add substantial toxicity compared with doxorubicin alone. Pharmacodynamic study supports this concept. The recommended dose for the phase II part for doxorubicin was 75 mg/m2 Clin Cancer Res; 24(21); 5239-49. ©2018 AACR.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sarcoma/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Camundongos , Gradação de Tumores , Estadiamento de Neoplasias , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Sarcoma/diagnóstico , Sarcoma/metabolismo , Sarcoma/mortalidadeRESUMO
Soft tissue sarcomas (STS) are malignant tumors of mesenchymal origin and represent around 1% of adult cancers, being a very heterogeneous group of tumors with more than 50 different subtypes. The Wnt signaling pathway is involved in the development and in the regulation, self-renewal, and differentiation of mesenchymal stem cells, and plays a role in sarcomagenesis. In this study, we have tested pharmacologic inhibition of Wnt signaling mediated by disruption of TCF/ß-catenin binding and AXIN stabilization, being the first strategy more efficient in reducing cell viability and downstream effects. We have shown that disruption of TCF/ß-catenin binding with PKF118-310 produces in vitro antitumor activity in a panel of prevalent representative STS cell lines and primary cultures. At the molecular level, PKF118-310 treatment reduced ß-catenin nuclear localization, reporter activity, and target genes, resulting in an increase in apoptosis. Importantly, combination of PKF118-310 with doxorubicin resulted in enhanced reduction of cell viability, suggesting that Wnt inhibition could be a new combination regime in these patients. Our findings support the usefulness of Wnt inhibitors as new therapeutic strategies for the prevalent STS. Mol Cancer Ther; 16(6); 1166-76. ©2017 AACR.