31 research outputs found
Development of a novel polyamide-based agent to inhibit EVI1 function
The EVI1 gene at chromosome 3q26 is associated with acute myeloid leukemogenesis, due to both chromosomal rearrangement and to overexpression in the absence of rearrangement. Some rearrangements such as t(3;3) and inv(3) result in overexpression of EVI1 protein, while translocation t(3;21) yields an AML1-MDS1-EVI1 (AME) fusion protein. EVI1 possesses two zinc finger domains, an N-terminal domain with fingers 1–7, which binds to GACAAGATA, and a C-terminal domain (fingers 8–10) which binds GAAGATGAG. Inhibition of EVI1 function with a small molecule compound may provide a targeted therapy for EVI1-expressing leukemias. As a first step towards inhibiting the leukemogenic function of EVI1, we performed structure-function studies on both EVI1 and AME protein to determine what domains are critical for malignant transformation activity. Assays were Rat1 fibroblasts in a soft agar colony forming assay for EVI1;
primary bone marrow cells in a serial replating assay for AME.
Both assays revealed that mutation of arginine 205 in zinc finger 6 of EVI1, which completely abrogates sequencespecific DNA binding via the N-terminal zinc finger domain, resulted in complete loss of transforming activity; mutations in other domains, such as the C-terminal zinc finger domain, CtBP binding domain, and the domains of AML1 had less of an effect or no effect on transforming activity. In an effort to inhibit EVI1 leukemogenic function, we developed a polyamide, DH-IV-298, designed to block zinc fingers 1–7 binding to the GACAAGATA motif. DNAseI footprinting revealed a specific interaction between DH-IV-298 and the GACAAGATA motif; no significant interaction was observed elsewhere; a mismatch polyamide failed to footprint at equivalent concentrations; and DH-IV-298 failed to bind to a control DNA lacking the GACAAGATA motif. Electromobility shift assay showed that, at a 1:1 polyamide:DNA ratio, DH-IV-298 lowered EVI1:DNA affinity by over 98%, while mismatch was significantly less effective (74% reduction). To assess the effect of DH-IV-298 on EVI1 binding to DNA in vivo, we performed CAT reporter assays in a NIH-3T3-derived cell line with a chromosome-embedded tet-inducible EVI1-VP16 as well as a EVI1-responsive CAT reporter. Removal of tetracycline resulted in a four-fold increase in CAT activity that was completely blocked by DH-IV-298. The mismatch polyamide was significantly less effective than DH-IV-298. Further studies are being performed to assess the effect on endogenous gene expression, and on growth of leukemic cells that express EVI1. These studies provide evidence that a cell permeable small molecule compound may effectively block the activity of a leukemogenic transcription factor
EuReCa ONE—27 Nations, ONE Europe, ONE Registry A prospective one month analysis of out-of-hospital cardiac arrest outcomes in 27 countries in Europe
AbstractIntroductionThe aim of the EuReCa ONE study was to determine the incidence, process, and outcome for out of hospital cardiac arrest (OHCA) throughout Europe.MethodsThis was an international, prospective, multi-centre one-month study. Patients who suffered an OHCA during October 2014 who were attended and/or treated by an Emergency Medical Service (EMS) were eligible for inclusion in the study. Data were extracted from national, regional or local registries.ResultsData on 10,682 confirmed OHCAs from 248 regions in 27 countries, covering an estimated population of 174 million. In 7146 (66%) cases, CPR was started by a bystander or by the EMS. The incidence of CPR attempts ranged from 19.0 to 104.0 per 100,000 population per year. 1735 had ROSC on arrival at hospital (25.2%), Overall, 662/6414 (10.3%) in all cases with CPR attempted survived for at least 30 days or to hospital discharge.ConclusionThe results of EuReCa ONE highlight that OHCA is still a major public health problem accounting for a substantial number of deaths in Europe.EuReCa ONE very clearly demonstrates marked differences in the processes for data collection and reported outcomes following OHCA all over Europe. Using these data and analyses, different countries, regions, systems, and concepts can benchmark themselves and may learn from each other to further improve survival following one of our major health care events
Predictive molecular markers of response to targeted therapies in gastrointestinal cancers
Les thérapies moléculaires ciblées ont changé la prise en charge des patients atteints de cancer, et en particulier dans le cancer colorectal (CCR). Il est important d’identifier des biomarqueurs de sensibilité ou de résistance à ces traitements. En premier, la signalisation en aval de l’EGFR au niveau tumoral pourrait conditionner la réponse au cétuximab dans les cancers colorectaux (CCR). Notre premier travail a évalué le niveau d’expression tumorale de phosphoprotéines de signalisation en aval de l’EGFR (p-MEK, p-ERK1/2, p-AKT, p-GSK3b, p-P70S6K) analysés par Bioplex phosphoprotein array chez 42 patients avec un CCR métastatique, traités par anti-EGFR. L’expression de p-P70S6K est plus faible chez les patients répondeurs (p=0,02). La survie sans progression (SSP) est supérieure en cas d’expression faible de p-P70S6K (p=0,0001) et p-MEK (p=0,0006). p-MEK et p-P70S6K ont une expression plus élevée chez les KRAS mutés et apparaissent comme deux marqueurs pronostiques indépendants de KRAS (HR 0,34, p=0,01 et HR 0,42, p=0,03). Ainsi, le niveau d’expression des phosphoprotéines en aval de l’EGFR pourrait prédire la réponse et la SSP dans les CCR traités par anti-EGFR, indépendamment du statut KRAS. Il est difficile dans certain cas d’avoir accès au tissu tumoral. L’ADN circulant (cADN) dans les stades avancés de cancer peut aider à la caractérisation moléculaire des tumeurs, en tant que biopsie. Notre deuxième travail a étudié la faisabilité, la sensibilité et la spécificité d’une technique de spectrométrie de masse (Sequenom) pour détecter des mutations (238 mutations parmi 19 oncogènes) à partir du tissu tumoral et du cADN de 105 patients ayant un cancer avancé. La concentration médiane de cADN était de 17ng/ml de plasma (0,5-1600), soit 3 fois le niveau chez les volontaires sains. En analyse multivariée, la concentration de cADN, l’albumine et l’état général étaient des facteurs prédictifs indépendants de la survie globale des patients. De plus, il existait une concordance élevée des statuts mutationnels (KRAS, BRAF et PIK3CA) entre le tissu tumoral et le cADN dans plusieurs types tumoraux (CCR, sein, mélanome): un taux de concordance de 70% pour le gène KRAS et de 100% pour le gène BRAF ont été retrouvés dans le CCR. Notre Étude suggère que l’analyse du cADN pourrait être un matériel utilisable pour la recherche de mutations, notamment dans le suivi des patients ayant un cancer du colon traités par thérapies ciblées. Notre travail a donc montré l’intérêt de poursuivre l’étude de facteurs moléculaires qui pourraient prédire la réponse ou la résistance à des thérapies ciblées utilisées dans les cancers du colon, au niveau du tissu tumoral (phosphoprotéines) ou au niveau du sang (cADN).Especially in CRC, it is important to identify molecular targeted therapies biomarkers. First, additional markers of resistance to KRAS mutations could predict resistance to anti-epidermal growth factor receptor (EGFR) antibodies in advanced colorectal cancer (CRC). In our first study, in a series of 42 patients with advanced CRC treated with cetuximab/panitumumab, for whom KRAS status was previously determined, we retrospectively analyzed the intratumor expression of EGFR downstream signaling phosphoproteins of the RAS/MAPK and PI3K/AKT pathways (pERK1/2, pMEK1, pAKT, pP70S6K and pGSK3beta) using Bio-Plex phosphoprotein array. The expression of all the phosphoproteins was higher in KRAS mutated tumors than in WT tumors. The expression of pP70S6K was lower in responders than in nonresponder patients. In multivariate analysis, PFS was shorter for patients with high pMEK1 or pP70S6K expression, independently of KRAS status, as OS for patients with high pP70S6K expression. Our results suggest the importance of EGFR downstream signaling phosphoproteins expression in addition to KRAS status to define the subgroup of patients who will not benefit from anti-EGFR therapy. We hypothesized that circulating plasma DNA (cpDNA) in advanced cancer patients is largely derived from tumor, and can be utilized for tumor mutation sequencing when repeat biopsy is not feasible. In our second study, we utilized the Sequenom MassArray System and OncoCarta panel for somatic mutation profiling. Matched samples, acquired from the same patient but at different time points were evaluated; these comprised formalin-fixed paraffin-embedded (FFPE) archival tumor tissue (primary and/or metastatic) and cpDNA. The feasibility, sensitivity, and specificity of this high-throughput, multiplex mutation detection approach was tested utilizing specimens acquired from 105 patients with solid tumors referred for participation in Phase I trials of molecularly targeted drugs. The median cpDNA concentration was 17 ng/ml (range: 0.5-1600); this was 3-fold higher than in healthy volunteers. In multivariate analyses, cpDNA concentration, albumin, and performance status remained independent predictors of OS. We also observed high detection concordance for critical "hot-spot" mutations (70% for KRAS, 100% for BRAF) in matched cpDNA and archival tumor tissue. This multiplex sequencing assay can be utilized to detectsomatic mutations from plasma in advanced cancer patients, when safe repeat tumor biopsy is not feasible and genomic analysis of archival tumor is deemed insufficient. Our work did show the importance to search for molecular markers to predict response to targeted therapies, both in tumor tissu (phosphoproteins) and in blood (cpDNA)
Marqueurs moléculaires prédictifs de réponse aux thérapies ciblées dans les cancers digestifs
Especially in CRC, it is important to identify molecular targeted therapies biomarkers. First, additional markers of resistance to KRAS mutations could predict resistance to anti-epidermal growth factor receptor (EGFR) antibodies in advanced colorectal cancer (CRC). In our first study, in a series of 42 patients with advanced CRC treated with cetuximab/panitumumab, for whom KRAS status was previously determined, we retrospectively analyzed the intratumor expression of EGFR downstream signaling phosphoproteins of the RAS/MAPK and PI3K/AKT pathways (pERK1/2, pMEK1, pAKT, pP70S6K and pGSK3beta) using Bio-Plex phosphoprotein array. The expression of all the phosphoproteins was higher in KRAS mutated tumors than in WT tumors. The expression of pP70S6K was lower in responders than in nonresponder patients. In multivariate analysis, PFS was shorter for patients with high pMEK1 or pP70S6K expression, independently of KRAS status, as OS for patients with high pP70S6K expression. Our results suggest the importance of EGFR downstream signaling phosphoproteins expression in addition to KRAS status to define the subgroup of patients who will not benefit from anti-EGFR therapy. We hypothesized that circulating plasma DNA (cpDNA) in advanced cancer patients is largely derived from tumor, and can be utilized for tumor mutation sequencing when repeat biopsy is not feasible. In our second study, we utilized the Sequenom MassArray System and OncoCarta panel for somatic mutation profiling. Matched samples, acquired from the same patient but at different time points were evaluated; these comprised formalin-fixed paraffin-embedded (FFPE) archival tumor tissue (primary and/or metastatic) and cpDNA. The feasibility, sensitivity, and specificity of this high-throughput, multiplex mutation detection approach was tested utilizing specimens acquired from 105 patients with solid tumors referred for participation in Phase I trials of molecularly targeted drugs. The median cpDNA concentration was 17 ng/ml (range: 0.5-1600); this was 3-fold higher than in healthy volunteers. In multivariate analyses, cpDNA concentration, albumin, and performance status remained independent predictors of OS. We also observed high detection concordance for critical "hot-spot" mutations (70% for KRAS, 100% for BRAF) in matched cpDNA and archival tumor tissue. This multiplex sequencing assay can be utilized to detectsomatic mutations from plasma in advanced cancer patients, when safe repeat tumor biopsy is not feasible and genomic analysis of archival tumor is deemed insufficient. Our work did show the importance to search for molecular markers to predict response to targeted therapies, both in tumor tissu (phosphoproteins) and in blood (cpDNA).Les thérapies moléculaires ciblées ont changé la prise en charge des patients atteints de cancer, et en particulier dans le cancer colorectal (CCR). Il est important d’identifier des biomarqueurs de sensibilité ou de résistance à ces traitements. En premier, la signalisation en aval de l’EGFR au niveau tumoral pourrait conditionner la réponse au cétuximab dans les cancers colorectaux (CCR). Notre premier travail a évalué le niveau d’expression tumorale de phosphoprotéines de signalisation en aval de l’EGFR (p-MEK, p-ERK1/2, p-AKT, p-GSK3b, p-P70S6K) analysés par Bioplex phosphoprotein array chez 42 patients avec un CCR métastatique, traités par anti-EGFR. L’expression de p-P70S6K est plus faible chez les patients répondeurs (p=0,02). La survie sans progression (SSP) est supérieure en cas d’expression faible de p-P70S6K (p=0,0001) et p-MEK (p=0,0006). p-MEK et p-P70S6K ont une expression plus élevée chez les KRAS mutés et apparaissent comme deux marqueurs pronostiques indépendants de KRAS (HR 0,34, p=0,01 et HR 0,42, p=0,03). Ainsi, le niveau d’expression des phosphoprotéines en aval de l’EGFR pourrait prédire la réponse et la SSP dans les CCR traités par anti-EGFR, indépendamment du statut KRAS. Il est difficile dans certain cas d’avoir accès au tissu tumoral. L’ADN circulant (cADN) dans les stades avancés de cancer peut aider à la caractérisation moléculaire des tumeurs, en tant que biopsie. Notre deuxième travail a étudié la faisabilité, la sensibilité et la spécificité d’une technique de spectrométrie de masse (Sequenom) pour détecter des mutations (238 mutations parmi 19 oncogènes) à partir du tissu tumoral et du cADN de 105 patients ayant un cancer avancé. La concentration médiane de cADN était de 17ng/ml de plasma (0,5-1600), soit 3 fois le niveau chez les volontaires sains. En analyse multivariée, la concentration de cADN, l’albumine et l’état général étaient des facteurs prédictifs indépendants de la survie globale des patients. De plus, il existait une concordance élevée des statuts mutationnels (KRAS, BRAF et PIK3CA) entre le tissu tumoral et le cADN dans plusieurs types tumoraux (CCR, sein, mélanome): un taux de concordance de 70% pour le gène KRAS et de 100% pour le gène BRAF ont été retrouvés dans le CCR. Notre Étude suggère que l’analyse du cADN pourrait être un matériel utilisable pour la recherche de mutations, notamment dans le suivi des patients ayant un cancer du colon traités par thérapies ciblées. Notre travail a donc montré l’intérêt de poursuivre l’étude de facteurs moléculaires qui pourraient prédire la réponse ou la résistance à des thérapies ciblées utilisées dans les cancers du colon, au niveau du tissu tumoral (phosphoprotéines) ou au niveau du sang (cADN)
Marqueurs moléculaires prédictifs de réponse aux thérapies ciblées dans les cancers digestifs
Les thérapies moléculaires ciblées ont changé la prise en charge des patients atteints de cancer, et en particulier dans le cancer colorectal (CCR). Il est important d identifier des biomarqueurs de sensibilité ou de résistance à ces traitements. En premier, la signalisation en aval de l EGFR au niveau tumoral pourrait conditionner la réponse au cétuximab dans les cancers colorectaux (CCR). Notre premier travail a évalué le niveau d expression tumorale de phosphoprotéines de signalisation en aval de l EGFR (p-MEK, p-ERK1/2, p-AKT, p-GSK3b, p-P70S6K) analysés par Bioplex phosphoprotein array chez 42 patients avec un CCR métastatique, traités par anti-EGFR. L expression de p-P70S6K est plus faible chez les patients répondeurs (p=0,02). La survie sans progression (SSP) est supérieure en cas d expression faible de p-P70S6K (p=0,0001) et p-MEK (p=0,0006). p-MEK et p-P70S6K ont une expression plus élevée chez les KRAS mutés et apparaissent comme deux marqueurs pronostiques indépendants de KRAS (HR 0,34, p=0,01 et HR 0,42, p=0,03). Ainsi, le niveau d expression des phosphoprotéines en aval de l EGFR pourrait prédire la réponse et la SSP dans les CCR traités par anti-EGFR, indépendamment du statut KRAS. Il est difficile dans certain cas d avoir accès au tissu tumoral. L ADN circulant (cADN) dans les stades avancés de cancer peut aider à la caractérisation moléculaire des tumeurs, en tant que biopsie. Notre deuxième travail a étudié la faisabilité, la sensibilité et la spécificité d une technique de spectrométrie de masse (Sequenom) pour détecter des mutations (238 mutations parmi 19 oncogènes) à partir du tissu tumoral et du cADN de 105 patients ayant un cancer avancé. La concentration médiane de cADN était de 17ng/ml de plasma (0,5-1600), soit 3 fois le niveau chez les volontaires sains. En analyse multivariée, la concentration de cADN, l albumine et l état général étaient des facteurs prédictifs indépendants de la survie globale des patients. De plus, il existait une concordance élevée des statuts mutationnels (KRAS, BRAF et PIK3CA) entre le tissu tumoral et le cADN dans plusieurs types tumoraux (CCR, sein, mélanome): un taux de concordance de 70% pour le gène KRAS et de 100% pour le gène BRAF ont été retrouvés dans le CCR. Notre Étude suggère que l analyse du cADN pourrait être un matériel utilisable pour la recherche de mutations, notamment dans le suivi des patients ayant un cancer du colon traités par thérapies ciblées. Notre travail a donc montré l intérêt de poursuivre l étude de facteurs moléculaires qui pourraient prédire la réponse ou la résistance à des thérapies ciblées utilisées dans les cancers du colon, au niveau du tissu tumoral (phosphoprotéines) ou au niveau du sang (cADN).Especially in CRC, it is important to identify molecular targeted therapies biomarkers. First, additional markers of resistance to KRAS mutations could predict resistance to anti-epidermal growth factor receptor (EGFR) antibodies in advanced colorectal cancer (CRC). In our first study, in a series of 42 patients with advanced CRC treated with cetuximab/panitumumab, for whom KRAS status was previously determined, we retrospectively analyzed the intratumor expression of EGFR downstream signaling phosphoproteins of the RAS/MAPK and PI3K/AKT pathways (pERK1/2, pMEK1, pAKT, pP70S6K and pGSK3beta) using Bio-Plex phosphoprotein array. The expression of all the phosphoproteins was higher in KRAS mutated tumors than in WT tumors. The expression of pP70S6K was lower in responders than in nonresponder patients. In multivariate analysis, PFS was shorter for patients with high pMEK1 or pP70S6K expression, independently of KRAS status, as OS for patients with high pP70S6K expression. Our results suggest the importance of EGFR downstream signaling phosphoproteins expression in addition to KRAS status to define the subgroup of patients who will not benefit from anti-EGFR therapy. We hypothesized that circulating plasma DNA (cpDNA) in advanced cancer patients is largely derived from tumor, and can be utilized for tumor mutation sequencing when repeat biopsy is not feasible. In our second study, we utilized the Sequenom MassArray System and OncoCarta panel for somatic mutation profiling. Matched samples, acquired from the same patient but at different time points were evaluated; these comprised formalin-fixed paraffin-embedded (FFPE) archival tumor tissue (primary and/or metastatic) and cpDNA. The feasibility, sensitivity, and specificity of this high-throughput, multiplex mutation detection approach was tested utilizing specimens acquired from 105 patients with solid tumors referred for participation in Phase I trials of molecularly targeted drugs. The median cpDNA concentration was 17 ng/ml (range: 0.5-1600); this was 3-fold higher than in healthy volunteers. In multivariate analyses, cpDNA concentration, albumin, and performance status remained independent predictors of OS. We also observed high detection concordance for critical "hot-spot" mutations (70% for KRAS, 100% for BRAF) in matched cpDNA and archival tumor tissue. This multiplex sequencing assay can be utilized to detectsomatic mutations from plasma in advanced cancer patients, when safe repeat tumor biopsy is not feasible and genomic analysis of archival tumor is deemed insufficient. Our work did show the importance to search for molecular markers to predict response to targeted therapies, both in tumor tissu (phosphoproteins) and in blood (cpDNA).PARIS5-Bibliotheque electronique (751069902) / SudocPARIS-BIUM-Bib. électronique (751069903) / SudocSudocFranceF
Expression of pEGFR and pAKT as response-predictive biomarkers for RAS wild-type patients to anti-EGFR monoclonal antibodies in metastatic colorectal cancers.
International audienceBackground:RAS wild-type (RASw/t) tumours have been associated with better outcomes in patients with metastatic colorectal cancer (mCRC) treated with anti-EGFR monoclonal antibodies (mAb). We investigated the expression of EGFR downstream proteins under their active phosphorylated forms as potential markers in response to these patients.Methods:One-hundred tumour samples were collected from patients with mCRC refractory to FOLFOX and/or FOLFIRI and treated by a combination of chemotherapy with anti-EGFR mAb. The outcomes were measured on response evaluation criteria in solid tumour (RECIST), progression-free survival (PFS) and overall survival (OS). All samples were assessed for RAS and BRAF mutations, and the key phosphorylated proteins of EGFR downstream signalling were quantitatively analysed using the BioPlex Protein array.Results:Among the 60 RASw/t patients, 45.0% achieved a complete or partial response when treated with anti-EGFR mAb. Expression of pAKT, pERK1/2 and pMEK1 was significantly lower in RASw/t patients (P=0.0246; P=0.004; P=0.0110, respectively). The response rate was significantly higher for RASw/t patients who express pEGFR and pAKT (P=0.0258; P=0.0277, respectively).Conclusions:Overexpression of pEGFR and pAKT may predict the response rate in RASw/t patients treated with anti-EGFR mAb. On the basis of our results, we hypothesise that the association of anti-EGFR mAb and anti-AKT therapies could be of interest
Role of circulating tumor DNA in the management of patients with colorectal cancer
International audienceColorectal cancer is a major health burden with a prognosis that has been improved with the progresses in diagnosis and the advance of chemotherapy and personalized medicine. However, because of intra-tumor heterogeneity, clonal evolution and selection, tumors often develop resistance to treatments. "Liquid biopsy" is a minimally invasive method, based on analysis of tumor-specific material in peripheral blood samples of patients. Analysis of tumor specific genetic or epigenetic alterations in cell-free circulating nucleic acids may reflect the molecular heterogeneity of the underlying disease process and serial testing could allow to monitor its temporal genomic changing without using re-biopsy. In this review, we focused on the role of circulating tumor DNA (ctDNA) as a biomarker in the management of patients with colorectal cancer at early and advanced stages. Through recent studies, we described its promising clinical applications for diagnosis, detection of recurrence after surgery and monitoring for tumor response or therapeutic resistance in metastatic setting. Such recent developments offer new perspectives for personalized medicine in colorectal cancer but still needs some standardized detection methods and further studies to validate its use in clinical routine