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1.
Cancers (Basel) ; 12(12)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255425

RESUMO

Spontaneous T cell responses to tumor-associated antigens (TAs) in the peripheral blood of patients with non-small-cell lung cancer (NSCLC) may be relevant for postoperative survival. However, the conditions underlying these T cell responses remain unclear. We quantified the levels of 27 cytokines in the peripheral blood and tumor tissues from treatment-naïve patients with NSCLC (n = 36) and analyzed associations between local and systemic cytokine profiles and both TA-specific T cell responses and clinical parameters. We defined T cell responders as patients with circulating T cells that were reactive to TAs and T cell nonresponders as patients without detectable TA-specific T cells. TA-specific T cell responses were correlated with serum cytokine levels, particularly the levels of interleukin(IL)-4 and granulocyte colony-stimulating factor (G-CSF), but poorly correlated with the cytokine levels in tumor tissues. Nonresponders showed significantly higher serum IL-4 levels than responders (p = 0.03); the predicted probability of being a responder was higher for individuals with low serum IL-4 levels. In multivariable Cox regression analyses, in addition to IL-4 (hazard ratio (HR) 2.8 (95% confidence interval (CI): 0.78-9.9); p = 0.116), the age-adjusted IL-8 level (HR 3.9 (95% CI: 1.05-14.5); p = 0.042) predicted tumor recurrence. However, this study included data for many cytokines without adjustment for multiple testing; thus, the observed differences in IL-4 or IL-8 levels might be incidental findings. Therefore, additional studies are necessary to confirm these results.

2.
Nature ; 588(7836): 157-163, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239784

RESUMO

Janus kinases (JAKs) mediate responses to cytokines, hormones and growth factors in haematopoietic cells1,2. The JAK gene JAK2 is frequently mutated in the ageing haematopoietic system3,4 and in haematopoietic cancers5. JAK2 mutations constitutively activate downstream signalling and are drivers of myeloproliferative neoplasm (MPN). In clinical use, JAK inhibitors have mixed effects on the overall disease burden of JAK2-mutated clones6,7, prompting us to investigate the mechanism underlying disease persistence. Here, by in-depth phosphoproteome profiling, we identify proteins involved in mRNA processing as targets of mutant JAK2. We found that inactivation of YBX1, a post-translationally modified target of JAK2, sensitizes cells that persist despite treatment with JAK inhibitors to apoptosis and results in RNA mis-splicing, enrichment for retained introns and disruption of the transcriptional control of extracellular signal-regulated kinase (ERK) signalling. In combination with pharmacological JAK inhibition, YBX1 inactivation induces apoptosis in JAK2-dependent mouse and primary human cells, causing regression of the malignant clones in vivo, and inducing molecular remission. This identifies and validates a cell-intrinsic mechanism whereby differential protein phosphorylation causes splicing-dependent alterations of JAK2-ERK signalling and the maintenance of JAK2V617F malignant clones. Therapeutic targeting of YBX1-dependent ERK signalling in combination with JAK2 inhibition could thus eradicate cells harbouring mutations in JAK2.

3.
Cell Death Dis ; 11(10): 875, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33070156

RESUMO

Since metastatic colorectal cancer (CRC) is a leading cause of cancer-related death, therapeutic approaches overcoming primary and acquired therapy resistance are an urgent medical need. In this study, the efficacy and toxicity of high-affinity inhibitors targeting antiapoptotic BCL-2 proteins (BCL-2, BCL-XL, and MCL-1) were evaluated. By RNA sequencing analysis of a pan-cancer cohort comprising >1500 patients and subsequent prediction of protein activity, BCL-XL was identified as the only antiapoptotic BCL-2 protein that is overactivated in CRC. Consistently, pharmacologic and genetic inhibition of BCL-XL induced apoptosis in human CRC cell lines. In a combined treatment approach, targeting BCL-XL augmented the efficacy of chemotherapy in vitro, in a murine CRC model, and in human ex vivo derived CRC tissue cultures. Collectively, these data show that targeting of BCL-XL is efficient and safe in preclinical CRC models, observations that pave the way for clinical translation.

4.
Support Care Cancer ; 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32885314

RESUMO

PURPOSE: Despite promising achievements in precision cancer medicine (PCM), participating patients are still faced with manifold uncertainties, especially regarding a potential treatment benefit of molecular diagnostics (MD). Hence, MD poses considerable challenges for patient information and communication. To meet these challenges, healthcare professionals need to gain deeper insight into patients' subjective experiences. Therefore, this qualitative study examined information aspects of MD programs in cancer patients. METHODS: In two German Comprehensive Cancer Centers, 30 cancer patients undergoing MD participated in semi-structured interviews on information transfer and information needs regarding MD. Additionally, patients provided sociodemographic and medical data and indicated their subjective level of information (visual analogue scale, VAS, 0-10). RESULTS: On average patients had high levels of information (mean = 7, median = 8); nevertheless 20% (n = 6) showed an information level below 5 points. Qualitative analysis revealed that patients show limited understanding of the complex background of MD and have uncertainties regarding their personal benefit. Further, patients described unmet information needs. Existential threat in awaiting the results was experienced as burdensome. To withstand the strains of their situation, patients emphasized the importance of trusting their physician. CONCLUSION: The challenges in PCM consist in providing unambiguous information, especially concerning treatment benefit, and providing guidance and support. Therefore, psycho-oncology needs to develop guidelines for adequate patient communication in order to help healthcare providers and cancer patients to handle these challenges in the developing field of PCM.

5.
Nat Commun ; 11(1): 4527, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913197

RESUMO

Evasion of programmed cell death represents a critical form of oncogene addiction in cancer cells. Understanding the molecular mechanisms underpinning cancer cell survival despite the oncogenic stress could provide a molecular basis for potential therapeutic interventions. Here we explore the role of pro-survival genes in cancer cell integrity during clonal evolution in non-small cell lung cancer (NSCLC). We identify gains of MCL-1 at high frequency in multiple independent NSCLC cohorts, occurring both clonally and subclonally. Clonal loss of functional TP53 is significantly associated with subclonal gains of MCL-1. In mice, tumour progression is delayed upon pharmacologic or genetic inhibition of MCL-1. These findings reveal that MCL-1 gains occur with high frequency in lung adenocarcinoma and can be targeted therapeutically.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Evolução Clonal , Variações do Número de Cópias de DNA , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Progressão da Doença , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Transgênicos , Mutação , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Cultura Primária de Células , Estudos Prospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , RNA-Seq , Estudos Retrospectivos , Esferoides Celulares , Tiofenos/farmacologia , Tiofenos/uso terapêutico , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Proteína Supressora de Tumor p53/genética , Microtomografia por Raio-X
7.
J Hepatol ; 73(6): 1347-1359, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32598967

RESUMO

BACKGROUND & AIMS: Selective elimination of virus-infected hepatocytes occurs through virus-specific CD8 T cells recognizing peptide-loaded MHC molecules. Herein, we report that virus-infected hepatocytes are also selectively eliminated through a cell-autonomous mechanism. METHODS: We generated recombinant adenoviruses and genetically modified mouse models to identify the molecular mechanisms determining TNF-induced hepatocyte apoptosis in vivo and used in vivo bioluminescence imaging, immunohistochemistry, immunoblot analysis, RNAseq/proteome/phosphoproteome analyses, bioinformatic analyses, mitochondrial function tests. RESULTS: We found that TNF precisely eliminated only virus-infected hepatocytes independently of local inflammation and activation of immune sensory receptors. TNF receptor I was equally relevant for NF-kB activation in healthy and infected hepatocytes, but selectively mediated apoptosis in infected hepatocytes. Caspase 8 activation downstream of TNF receptor signaling was dispensable for apoptosis in virus-infected hepatocytes, indicating an unknown non-canonical cell-intrinsic pathway promoting apoptosis in hepatocytes. We identified a unique state of mitochondrial vulnerability in virus-infected hepatocytes as the cause for this non-canonical induction of apoptosis through TNF. Mitochondria from virus-infected hepatocytes showed normal biophysical and bioenergetic functions but were characterized by reduced resilience to calcium challenge. In the presence of unchanged TNF-induced signaling, reactive oxygen species-mediated calcium release from the endoplasmic reticulum caused mitochondrial permeability transition and apoptosis, which identified a link between extrinsic death receptor signaling and cell-intrinsic mitochondrial-mediated caspase activation. CONCLUSION: Our findings reveal a novel concept in immune surveillance by identifying a cell-autonomous defense mechanism that selectively eliminates virus-infected hepatocytes through mitochondrial permeability transition. LAY SUMMARY: The liver is known for its unique immune functions. Herein, we identify a novel mechanism by which virus-infected hepatocytes can selectively eliminate themselves through reduced mitochondrial resilience to calcium challenge.

9.
JAMA Oncol ; 6(8): 1241-1246, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32469385

RESUMO

Importance: Adjuvant imatinib is associated with improved recurrence-free survival (RFS) when administered after surgery to patients with operable gastrointestinal stromal tumor (GIST), but its influence on overall survival (OS) has remained uncertain. Objective: To evaluate the effect of adjuvant imatinib on OS of patients who have a high estimated risk for GIST recurrence after macroscopically complete surgery. Design, Setting, and Participants: In this open-label, randomized (1:1), multicenter phase 3 clinical trial conducted in Finland, Germany, Norway, and Sweden, 400 patients who had undergone macroscopically complete surgery for GIST with a high estimated risk for recurrence according to the modified National Institutes of Health Consensus Criteria were enrolled between February 2004 and September 2008. Data for this follow-up analysis were analyzed from September to November, 2019. Interventions: Imatinib 400 mg/d administered orally for either 12 months or 36 months after surgery. Main Outcomes And Measures: The primary end point was RFS; the secondary objectives included OS and treatment safety. Results: The intention-to-treat cohort consisted of 397 patients (12-month group, 199; 36-month group, 198; 201 men and 196 women; median [IQR] age, 62 (51-69) years and 60 (51-67) years, during a median follow-up time of 119 months after the date of randomization, 194 RFS events and 96 OS events were recorded in the intention-to-treat population. Five-year and 10-year RFS was 71.4% and 52.5%, respectively, in the 36-month group and 53.0% and 41.8% in the 12-month group (hazard ratio [HR], 0.66; 95% CI, 0.49-0.87; P = .003). In the 36-month group, 5-year OS and 10-year OS rates were 92.0% and 79.0%, respectively, and in the 12-month group 85.5% and 65.3% (HR, 0.55; 95% CI, 0.37-0.83; P = .004). The results were similar in the efficacy population, from which 15 patients who did not have GIST in central pathology review and 24 patients who had intra-abdominal metastases removed at surgery were excluded (36-month group, 10-year OS 81.6%; 12-month group, 66.8%; HR, 0.50; 95% CI, 0.32-0.80; P = .003). No new safety signals were detected. Conclusions and Relevance: Three years of adjuvant imatinib is superior in efficacy compared with 1 year of imatinib. Approximately 50% of deaths may be avoided during the first 10 years of follow-up after surgery with longer adjuvant imatinib treatment. Trial Registration: ClinicalTrials.gov Identifier: NCT00116935.

10.
Am J Hematol ; 95(7): 824-833, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32279331

RESUMO

We report on 18 patients with myeloid neoplasms and associated tyrosine kinase (TK) fusion genes on treatment with the TK inhibitors (TKI) ruxolitinib (PCM1-JAK2, n = 8; BCR-JAK2, n = 1) and imatinib, nilotinib or dasatinib (ETV6-ABL1, n = 9). On ruxolitinib (median 24 months, range 2-36 months), a complete hematologic response (CHR) and complete cytogenetic response (CCR) was achieved by five of nine and two of nine patients, respectively. However, ruxolitinib was stopped in eight of nine patients because of primary resistance (n = 3), progression (n = 3) or planned allogeneic stem cell transplantation (allo SCT, n = 2). At a median of 36 months (range 4-78 months) from diagnosis, five of nine patients are alive: four of six patients after allo SCT and one patient who remains on ruxolitinib. In ETV6-ABL1 positive patients, a durable CHR was achieved by four of nine patients (imatinib with one of five, nilotinib with two of three, dasatinib with one of one). Because of inadequate efficacy (lack of hematological and/or cytogenetic/molecular response), six of nine patients (imatinib, n = 5; nilotinib, n = 1) were switched to nilotinib or dasatinib. At a median of 23 months (range 3-60 months) from diagnosis, five of nine patients are in CCR or complete molecular response (nilotinib, n = 2; dasatinib, n = 2; allo SCT, n = 1) while two of nine patients have died. We conclude that (a) responses on ruxolitinib may only be transient in the majority of JAK2 fusion gene positive patients with allo SCT being an important early treatment option, and (b) nilotinib or dasatinib may be more effective than imatinib to induce durable complete remissions in ETV6-ABL1 positive patients.


Assuntos
Neoplasias Hematológicas , Transtornos Mieloproliferativos , Proteínas de Fusão Oncogênica , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Tirosina Quinases , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Seguimentos , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/enzimologia , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/enzimologia , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/mortalidade , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Taxa de Sobrevida
11.
Cancer Res ; 80(11): 2394-2406, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32041835

RESUMO

Recent clinical findings in patients with chronic myeloid leukemia (CML) suggest that the risk of molecular recurrence after stopping tyrosine kinase inhibitor (TKI) treatment substantially depends on an individual's leukemia-specific immune response. However, it is still not possible to prospectively identify patients that will remain in treatment-free remission (TFR). Here, we used an ordinary differential equation model for CML, which explicitly includes an antileukemic immunologic effect, and applied it to 21 patients with CML for whom BCR-ABL1/ABL1 time courses had been quantified before and after TKI cessation. Immunologic control was conceptually necessary to explain TFR as observed in about half of the patients. Fitting the model simulations to data, we identified patient-specific parameters and classified patients into three different groups according to their predicted immune system configuration ("immunologic landscapes"). While one class of patients required complete CML eradication to achieve TFR, other patients were able to control residual leukemia levels after treatment cessation. Among them were a third class of patients that maintained TFR only if an optimal balance between leukemia abundance and immunologic activation was achieved before treatment cessation. Model simulations further suggested that changes in the BCR-ABL1 dynamics resulting from TKI dose reduction convey information about the patient-specific immune system and allow prediction of outcome after treatment cessation. This inference of individual immunologic configurations based on treatment alterations can also be applied to other cancer types in which the endogenous immune system supports maintenance therapy, long-term disease control, or even cure. SIGNIFICANCE: This mathematical modeling approach provides strong evidence that different immunologic configurations in patients with CML determine their response to therapy cessation and that dose reductions can help to prospectively infer different risk groups.See related commentary by Triche Jr, p. 2083.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Inibidores de Proteínas Quinases , Recidiva , Indução de Remissão
12.
Cell Death Dis ; 11(1): 56, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31974356

RESUMO

The original version of this article contained an error in the name of one of the co-authors (Erika Owsley). This has been corrected in the PDF and HTML versions.

13.
Eur J Haematol ; 104(2): 125-137, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31758597

RESUMO

INTRODUCTION: Targeting the cell cycle machinery represents a rational therapeutic approach in myelodysplastic syndromes (MDS) and secondary acute myeloid leukemia (sAML). Despite substantial response rates, clinical use of the PLK inhibitor volasertib has been hampered by elevated side effects such as neutropenia and infections. OBJECTIVES: The primary objective was to analyse whether a reduced dose of volasertib was able to limit toxic effects on the healthy haematopoiesis while retaining its therapeutic effect. METHODS: Bone marrow mononuclear cells (BMMNCs) of patients with MDS/sAML (n = 73) and healthy controls (n = 28) were treated with volasertib (1 µM to 1 nM) or vehicle control. Short-term viability analysis was performed by flow cytometry after 72 hours. For long-term viability analysis, colony-forming capacity was assessed after 14 days. Protein expression of RIPK3 and MCL-1 was quantified via flow cytometry. RESULTS: Reduced dose levels of volasertib retained high cell death-inducing efficacy in primary human stem and progenitor cells of MDS/sAML patients without affecting healthy haematopoiesis in vitro. Interestingly, volasertib reduced colony-forming capacity and cell survival independent of clinical stage or mutational status. CONCLUSIONS: Volasertib offers a promising therapeutic approach in patients with adverse prognostic profile. RIPK3 and MCL-1 might be potential biomarkers for sensitivity to volasertib treatment.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Hematopoese/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Pteridinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Proteínas de Ciclo Celular/metabolismo , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Masculino , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/biossíntese , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Pteridinas/efeitos adversos , Proteína Serina-Treonina Quinases de Interação com Receptores/biossíntese
14.
Artigo em Inglês | MEDLINE | ID: mdl-31843992

RESUMO

X-chromosome-linked inhibitor of apoptosis protein (XIAP) controls cell survival in several regulated cell death pathways and coordinates a range of inflammatory signaling events. Initially identified as a caspase-binding protein, it was considered to be primarily involved in blocking apoptosis from both intrinsic as well as extrinsic triggers. However, XIAP also prevents TNF-mediated, receptor-interacting protein 3 (RIPK3)-dependent cell death, by controlling RIPK1 ubiquitylation and preventing inflammatory cell death. The identification of patients with germline mutations in XIAP (termed XLP-2 syndrome) pointed toward its role in inflammatory signaling. Indeed, XIAP also mediates nucleotide-binding oligomerization domain-containing 2 (NOD2) proinflammatory signaling by promoting RIPK2 ubiquitination within the NOD2 signaling complex leading to NF-κB and MAPK activation and production of inflammatory cytokines and chemokines. Overall, XIAP is a critical regulator of multiple cell death and inflammatory pathways making it an attractive drug target in tumors and inflammatory diseases.

15.
Cell Death Dis ; 10(10): 700, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31541082

RESUMO

The pediatric immune deficiency X-linked proliferative disease-2 (XLP-2) is a unique disease, with patients presenting with either hemophagocytic lymphohistiocytosis (HLH) or intestinal bowel disease (IBD). Interestingly, XLP-2 patients display high levels of IL-18 in the serum even while in stable condition, presumably through spontaneous inflammasome activation. Recent data suggests that LPS stimulation can trigger inflammasome activation through a TNFR2/TNF/TNFR1 mediated loop in xiap-/- macrophages. Yet, the direct role TNFR2-specific activation plays in the absence of XIAP is unknown. We found TNFR2-specific activation leads to cell death in xiap-/- myeloid cells, particularly in the absence of the RING domain. RIPK1 kinase activity downstream of TNFR2 resulted in a TNF/TNFR1 cell death, independent of necroptosis. TNFR2-specific activation leads to a similar inflammatory NF-kB driven transcriptional profile as TNFR1 activation with the exception of upregulation of NLRP3 and caspase-11. Activation and upregulation of the canonical inflammasome upon loss of XIAP was mediated by RIPK1 kinase activity and ROS production. While both the inhibition of RIPK1 kinase activity and ROS production reduced cell death, as well as release of IL-1ß, the release of IL-18 was not reduced to basal levels. This study supports targeting TNFR2 specifically to reduce IL-18 release in XLP-2 patients and to reduce priming of the inflammasome components.

16.
Exp Hematol Oncol ; 8: 9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016067

RESUMO

Patients with Myelodysplastic Syndromes (MDS) and secondary Acute Myeloid Leukemia (sAML) have a very poor prognosis after failure of hypomethylating agents (HMA). Stem cell transplantation is the only effective salvage therapy, for which only a limited number of patients are eligible due to age and comorbidity. Combination therapy of venetoclax and azacitidine (5-AZA) seems to be a promising approach in myeloid malignancies, but data from patients with HMA failure are lacking. Furthermore, a considerable concern of combination regimens in elderly AML and MDS patients is the toxicity on the remaining healthy hematopoiesis. Here, we report in vitro data showing the impact of venetoclax and 5-AZA, alone or in combination, in a larger cohort of MDS/sAML patients (n = 21), even after HMA failure (n = 13). We especially focused on the effects on healthy hematopoiesis and the impact on colony forming capacity as a parameter for long-term effects. To the best of our knowledge, we show for the first time that venetoclax in combination with capped dose of 5-AZA targets cell malignancies, while sparing healthy hematopoiesis.

17.
Int J Cancer ; 145(8): 2292-2303, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30882891

RESUMO

This prospective trial aimed to investigate whether tumor-specific cKIT and PDGFRA mutations can be detected and quantified in circulating tumor (ct)DNA in patients with active GIST, and whether detection indicates disease activity. We included 25 patients with active disease and cKIT or PDGFRA mutations detected in tissue. Mutant ctDNA was detected in the peripheral blood plasma using allele-specific ligation (L-)PCR and droplet digital (d)PCR. CtDNA harboring tumor-specific cKIT or PDGFRA mutations was detected at least once in 16 out of 25 patients using L-PCR (64%) and in 20 out of 25 patients with dPCR (80%). Using dPCR, the absolute numbers of ctDNA fragments (DNA copies/ml) and the mutant allele frequency (MAF; in percent of wild-type control) strongly correlated with tumor size expressed as RECIST1.1 sum of diameter (SOD) in mm (ρ = 0.3719 and 0.408, respectively, p < 0.0001) and response status (ρ = 0.3939 and 0.392, respectively, p < 0.0001 and p < 0.001). Specificity of dPCR for detection of progression was 79.2% with a sensitivity of 55.2% and dPCR discriminated CR from active disease with a specificity of 96% and s sensitivity of 44.7%. With L-PCR, correlations of MAF with tumor size and response status were less prominent. Serial ctDNA measurement reflected individual disease courses over time. Targeted panel sequencing of four patients detected additional driver mutations in all cases and secondary resistance mutations in two cases. Thus, ctDNA indicates disease activity in patients with GIST and should be incorporated as companion biomarker in future prospective trials.


Assuntos
DNA Tumoral Circulante/genética , DNA de Neoplasias/genética , Tumores do Estroma Gastrointestinal/genética , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/sangue , DNA de Neoplasias/sangue , Feminino , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico
18.
Eur J Haematol ; 102(5): 437-441, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30725494

RESUMO

Acute myeloid leukemia (AML) is a disease of the elderly population and survival remains poor after failure of hypomethylating agents (HMA). The BCL-2 inhibitor venetoclax demonstrated activity as monotherapy and in combination with chemotherapy or HMA in AML. In this case series, patients with secondary AML (sAML) not eligible for intensive chemotherapy and refractory to HMA were treated with venetoclax within a named patient program at our tertiary cancer center in Salzburg, Austria. Between April 2017 and September 2018, seven patients with sAML received venetoclax therapy. Two out of seven patients achieved a complete remission upon venetoclax initiation with a PFS of 505 days and 352 days and another patient achieved complete peripheral blood blast clearing within nine days after start of venetoclax. Among the venetoclax responders, primary refractory disease to prior HMA therapy was documented, 2 patients harbored IDH1/IDH2 mutations and one patient had an antecedent myeloproliferative neoplasm. High BCL-2 and/or BIM expression in myeloblasts was found in venetoclax responders and response was significantly associated with overall survival (responders: 364 days versus non-responders: 24 days, P = 0.018). Venetoclax monotherapy is safe and is able to induce durable responses in elderly patients with secondary AML after treatment failure with HMA.


Assuntos
Antineoplásicos/uso terapêutico , Proteína 11 Semelhante a Bcl-2/genética , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Sulfonamidas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Proteína 11 Semelhante a Bcl-2/metabolismo , Biomarcadores Tumorais , Metilação de DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/diagnóstico , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Indução de Remissão , Retratamento , Resultado do Tratamento
19.
Sci Rep ; 9(1): 1325, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718557

RESUMO

Tumor volume is a parameter used to evaluate the performance of new therapies in lung cancer research. Conventional methods that are used to estimate tumor size in mouse models fail to provide fast and reliable volumetric data for tumors grown non-subcutaneously. Here, we evaluated the use of iodine-staining combined with micro-computed tomography (micro-CT) to estimate the tumor volume of ex vivo tumor-burdened lungs. We obtained fast high spatial resolution three-dimensional information of the lungs, and we demonstrated that iodine-staining highlights tumors and unhealthy tissue. We processed iodine-stained lungs for histopathological analysis with routine hematoxylin and eosin (H&E) staining. We compared the traditional tumor burden estimation performed manually with H&E histological slices with a semi-automated method using micro-CT datasets. In mouse models that develop lung tumors with well precise boundaries, the method that we describe here enables to perform a quick estimation of tumorous tissue volume in micro-CT images. Our method overestimates the tumor burden in tumors surrounded by abnormal tissue, while traditional histopathological analysis underestimates tumor volume. We propose to embed micro-CT imaging to the traditional workflow of tumorous lung analyses in preclinical cancer research as a strategy to obtain a more accurate estimation of the total lung tumor burden.


Assuntos
Meios de Contraste/farmacologia , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Carga Tumoral , Animais , Modelos Animais de Doenças , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Camundongos , Microtomografia por Raio-X
20.
Cell Death Differ ; 26(1): 53-67, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30242210

RESUMO

The hematopoietic system represents an organ system with an exceptional capacity for the production of mature blood cells from a small and mostly quiescent pool of hematopoietic stem cells (HSCs). This extraordinary capacity includes self-renewal but also the propensity to rapidly respond to extrinsic needs, such as acute infections, severe inflammation, and wound healing. In recent years, it became clear that inflammatory signals such as cytokines, chemokine and danger signals from pathogens (PAMPs) or dying cells (DAMPs) impact on HSCs, shaping their proliferation status, lineage bias, and repopulating ability and subsequently increasing the output of mature effector cells. However, inflammatory danger signals negatively impact on the capacity of HSCs to self-renew and to maintain their stem cell capabilities. This is evidenced in conditions of chronic inflammation where bone marrow failure may originate from HSC exhaustion. Even in hematopoietic cancers, inflammatory signals shape the phenotype of the malignant clone as exemplified by necrosome-dependent inflammation elicited during malignant transformation in acute myeloid leukemia. Accordingly, understanding the contribution of inflammatory signals, and specifically necroinflammation, to HSC integrity, HSC long-term functionality, and malignant transformation has attracted substantial research and clinical interest. In this review, we highlight recent developments and open questions at the interplay between inflammation, regulated necrosis, and HSC biology in the context of blood cell development, acute and chronic inflammation, and hematopoietic cancer.


Assuntos
Hematopoese/imunologia , Células-Tronco Hematopoéticas/imunologia , Inflamação/imunologia , Leucemia/imunologia , Necrose , Animais , Diferenciação Celular , Senescência Celular/imunologia , Citocinas/sangue , Citocinas/imunologia , Neoplasias Hematológicas/imunologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Inflamação/sangue , Leucemia/sangue , Leucemia/genética , Linfócitos/imunologia , Linfócitos/metabolismo , Necrose/sangue , Necrose/imunologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologia
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