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1.
Eur Radiol Exp ; 8(1): 29, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38467990

RESUMO

Hepatocellular carcinoma (HCC) comprises 75 to 85% of all primary liver cancers. Current guidelines recommend a biannual HCC surveillance using ultrasound (US) for high-risk patients. However, due to its low sensitivity for detection of early-stage HCC lesions, there is an urgency for more sensitive surveillance tools. Here, we describe the potential of a short MRI surveillance (SMS) protocol for HCC, including axial T1-weighted in-out phase, fat-saturated T2-weighted, and diffusion-weighted sequences. In this prospective, multicenter, patient cohort study, patients will be recruited from existing HCC surveillance cohorts of six medical centers in The Netherlands. Surveillance patients who undergo biannual US, will be invited for SMS on the same day for 3 years. In case of a suspicious finding on either US or SMS, patients will be invited for a full MRI liver protocol including gadolinium-based contrast agent intravenous injection within 2 weeks. To our knowledge, this will be the first study to perform a head-to-head comparison with a paired US-MRI design. We hypothesize that the sensitivity of SMS for detection of early-stage HCC will be higher than that of US leading to improved survival of surveillance patients through timely HCC diagnosis. Furthermore, we hypothesize that the SMS-HCC protocol will prove cost-effective.Relevance statement The US sensitivity for detecting early-stage HCC has been reported to be less than 50%. We expect that the proposed SMS will detect at least twice as many early-stage HCC lesions and therefore prove to be cost-effective. Key points • The low sensitivity of US necessitates better imaging tools for HCC screening.• This is the first study with a paired US-MRI design.• This design will allow a head-to-head comparison in both diagnostics and patient-acceptance.• We expect that SMS can contribute to a higher survival rate.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Meios de Contraste , Estudos Multicêntricos como Assunto
2.
bioRxiv ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38496490

RESUMO

Molecular mechanisms driving clonal aggressiveness in leukemia are not fully understood. We tracked and analyzed two mouse MLL-rearranged leukemic clones independently evolving towards higher aggressiveness. More aggressive subclones lost their growth differential ex vivo but restored it upon secondary transplantation, suggesting molecular memory of aggressiveness. Development of aggressiveness was associated with clone-specific gradual modulation of chromatin states and expression levels across the genome, with a surprising preferential trend of reversing the earlier changes between normal and leukemic progenitors. To focus on the core aggressiveness program, we identified genes with consistent changes of expression and chromatin marks that were maintained in vivo and ex vivo in both clones. Overexpressing selected core genes (Smad1 as aggressiveness driver, Irx5 and Plag1 as suppressors) affected leukemic progenitor growth in the predicted way and had convergent downstream effects on central transcription factors and repressive epigenetic modifiers, suggesting a broader regulatory network of leukemic aggressiveness.

3.
Leukemia ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424137

RESUMO

Differentiation therapy has proven to be a success story for patients with acute promyelocytic leukemia. However, the remaining subtypes of acute myeloid leukemia (AML) are treated with cytotoxic chemotherapies that have limited efficacy and a high likelihood of resistance. As differentiation arrest is a hallmark of AML, there is increased interest in developing differentiation-inducing agents to enhance disease-free survival. Here, we provide a comprehensive review of current reports and future avenues of nucleic acid therapeutics for AML, focusing on the use of targeted nucleic acid drugs to promote differentiation. Specifically, we compare and discuss the precision of small interfering RNA, small activating RNA, antisense oligonucleotides, and aptamers to modulate gene expression patterns that drive leukemic cell differentiation. We delve into preclinical and clinical studies that demonstrate the efficacy of nucleic acid-based differentiation therapies to induce leukemic cell maturation and reduce disease burden. By directly influencing the expression of key genes involved in myeloid maturation, nucleic acid therapeutics hold the potential to induce the differentiation of leukemic cells towards a more mature and less aggressive phenotype. Furthermore, we discuss the most critical challenges associated with developing nucleic acid therapeutics for myeloid malignancies. By introducing the progress in the field and identifying future opportunities, we aim to highlight the power of nucleic acid therapeutics in reshaping the landscape of myeloid leukemia treatment.

4.
Lancet Oncol ; 25(1): 137-146, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38081200

RESUMO

BACKGROUND: Guidelines are inconclusive on whether contrast-enhanced MRI using gadoxetic acid and diffusion-weighted imaging should be added routinely to CT in the investigation of patients with colorectal liver metastases who are scheduled for curative liver resection or thermal ablation, or both. Although contrast-enhanced MRI is reportedly superior than contrast-enhanced CT in the detection and characterisation of colorectal liver metastases, its effect on clinical patient management is unknown. We aimed to assess the clinical effect of an additional liver contrast-enhanced MRI on local treatment plan in patients with colorectal liver metastases amenable to local treatment, based on contrast-enhanced CT. METHODS: We did an international, multicentre, prospective, incremental diagnostic accuracy trial in 14 liver surgery centres in the Netherlands, Belgium, Norway, and Italy. Participants were aged 18 years or older with histological proof of colorectal cancer, a WHO performance status score of 0-4, and primary or recurrent colorectal liver metastases, who were scheduled for local therapy based on contrast-enhanced CT. All patients had contrast-enhanced CT and liver contrast-enhanced MRI including diffusion-weighted imaging and gadoxetic acid as a contrast agent before undergoing local therapy. The primary outcome was change in the local clinical treatment plan (decided by the individual clinics) on the basis of liver contrast-enhanced MRI findings, analysed in the intention-to-image population. The minimal clinically important difference in the proportion of patients who would have change in their local treatment plan due to an additional liver contrast-enhanced MRI was 10%. This study is closed and registered in the Netherlands Trial Register, NL8039. FINDINGS: Between Dec 17, 2019, and July 31, 2021, 325 patients with colorectal liver metastases were assessed for eligibility. 298 patients were enrolled and included in the intention-to-treat population, including 177 males (59%) and 121 females (41%) with planned local therapy based on contrast-enhanced CT. A change in the local treatment plan based on liver contrast-enhanced MRI findings was observed in 92 (31%; 95% CI 26-36) of 298 patients. Changes were made for 40 patients (13%) requiring more extensive local therapy, 11 patients (4%) requiring less extensive local therapy, and 34 patients (11%) in whom the indication for curative-intent local therapy was revoked, including 26 patients (9%) with too extensive disease and eight patients (3%) with benign lesions on liver contrast-enhanced MRI (confirmed by a median follow-up of 21·0 months [IQR 17·5-24·0]). INTERPRETATION: Liver contrast-enhanced MRI should be considered in all patients scheduled for local treatment for colorectal liver metastases on the basis of contrast-enhanced CT imaging. FUNDING: The Dutch Cancer Society and Bayer AG - Pharmaceuticals.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Masculino , Feminino , Humanos , Meios de Contraste , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/terapia , Neoplasias Colorretais/patologia
5.
Gastrointest Endosc ; 99(4): 548-556, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37890597

RESUMO

BACKGROUND AND AIMS: For a highly selected group of patients with unresectable perihilar cholangiocarcinoma (pCCA), liver transplantation (LT) is a treatment option. The Dutch screening protocol comprises nonregional lymph node (LN) assessment by EUS, and whenever LN metastases are identified, further LT screening is precluded. The aim of this study is to investigate the yield of EUS in patients with pCCA who are potentially eligible for LT. METHODS: In this retrospective, nationwide cohort study, all consecutive patients with suspected unresectable pCCA who underwent EUS in the screening protocol for LT were included from 2011 to 2021. During EUS, sampling of a "suspicious" nonregional LN was performed based on the endoscopist's discretion. The primary outcome was the added value of EUS, defined as the number of patients who were precluded from further screening because of malignant LNs. RESULTS: A total of 75 patients were included in whom 84 EUS procedures were performed, with EUS-guided tissue acquisition confirming malignancy in LNs in 3 of 75 (4%) patients. In the 43 who underwent surgical staging according to the protocol, nonregional LNs with malignancy were identified in 6 (14%) patients. Positive regional LNs were found in 7 patients in post-LT-resected specimens. CONCLUSIONS: Our current EUS screening for the detection of malignant LNs in patients with pCCA eligible for LT shows a limited but clinically important yield. EUS with systematic screening of all LN stations, both regional and nonregional, and the sampling of suspicious lymph nodes according to defined and set criteria could potentially increase this yield.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Transplante de Fígado , Humanos , Estudos de Coortes , Estudos Retrospectivos , Tumor de Klatskin/diagnóstico por imagem , Tumor de Klatskin/cirurgia , Tumor de Klatskin/patologia , Endossonografia/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/cirurgia , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Estadiamento de Neoplasias
6.
Ann Hematol ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37736806

RESUMO

Gene therapy represents a significant potential to revolutionize the field of hematology with applications in correcting genetic mutations, generating cell lines and animal models, and improving the feasibility and efficacy of cancer immunotherapy. Compared to different genetic engineering tools, clustered regularly interspaced short palindromic repeats (CRISPR) CRISPR-associated protein 9 (Cas9) emerged as an effective and versatile genetic editor with the ability to precisely modify the genome. The applications of genetic engineering in various hematological disorders have shown encouraging results. Monogenic hematological disorders can conceivably be corrected with single gene modification. Through the use of CRISPR-CAS9, restoration of functional red blood cells and hemostasis factors were successfully attained in sickle cell anemia, beta-thalassemia, and hemophilia disorders. Our understanding of hemato-oncology has been advanced via CRIPSR-CAS9 technology. CRISPR-CAS9 aided to build a platform of mutated genes responsible for cell survival and proliferation in leukemia. Therapeutic application of CRISPR-CAS9 when combined with chimeric antigen receptor (CAR) T cell therapy in multiple myeloma and acute lymphoblastic leukemia was feasible with attenuation of CAR T cell therapy pitfalls. Our review outlines the latest literature on the utilization of CRISPR-Cas9 in the treatment of beta-hemoglobinopathies and hemophilia disorders. We present the strategies that were employed and the findings of preclinical and clinical trials. Also, the review will discuss gene engineering in the field of hemato-oncology as a proper tool to facilitate and overcome the drawbacks of chimeric antigen receptor T cell therapy (CAR-T).

7.
Cell Rep ; 42(9): 113084, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37716355

RESUMO

Pediatric acute megakaryoblastic leukemia (AMKL) is an aggressive blood cancer associated with poor therapeutic response and high mortality. Here we describe the development of CBFA2T3-GLIS2-driven mouse models of AMKL that recapitulate the phenotypic and transcriptional signatures of the human disease. We show that an activating Ras mutation that occurs in human AMKL increases the penetrance and decreases the latency of CBF2AT3-GLIS2-driven AMKL. CBFA2T3-GLIS2 and GLIS2 modulate similar transcriptional networks. We identify the dominant oncogenic properties of GLIS2 that trigger AMKL in cooperation with oncogenic Ras. We find that both CBFA2T3-GLIS2 and GLIS2 alter the expression of a number of BH3-only proteins, causing AMKL cell sensitivity to the BCL2 inhibitor navitoclax both in vitro and in vivo, suggesting a potential therapeutic option for pediatric patients suffering from CBFA2T3-GLIS2-driven AMKL.


Assuntos
Leucemia Megacarioblástica Aguda , Animais , Camundongos , Criança , Humanos , Leucemia Megacarioblástica Aguda/tratamento farmacológico , Leucemia Megacarioblástica Aguda/genética , Compostos de Anilina , Sulfonamidas , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Repressoras
8.
Cell Rep Med ; 4(9): 101191, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37683650

RESUMO

Previous chemotherapy research has focused almost exclusively on apoptosis. Here, a standard frontline drug combination of cytarabine and idarubicin induces distinct features of caspase-independent, poly(ADP-ribose) polymerase 1 (PARP-1)-mediated programmed cell death "parthanatos" in acute myeloid leukemia (AML) cell lines (n = 3/10 tested), peripheral blood mononuclear cells from healthy human donors (n = 10/10 tested), and primary cell samples from patients with AML (n = 18/39 tested, French-American-British subtypes M4 and M5). A 3-fold improvement in survival rates is observed in the parthanatos-positive versus -negative patient groups (hazard ratio [HR] = 0.28-0.37, p = 0.002-0.046). Manipulation of PARP-1 activity in parthanatos-competent cells reveals higher drug sensitivity in cells that have basal PARP-1 levels as compared with those subjected to PARP-1 overexpression or suppression. The same trends are observed in RNA expression databases and support the conclusion that PARP-1 can have optimal levels for favorable chemotherapeutic responses.


Assuntos
Leucemia , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Apoptose , Linhagem Celular , Leucócitos Mononucleares , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico
9.
Int J Radiat Oncol Biol Phys ; 117(1): 45-52, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37037359

RESUMO

PURPOSE: To compare transarterial chemoembolization delivered with drug eluting beads (TACE-DEB) with stereotactioc body radiation therapy (SBRT) in patients with hepatocellular carcinoma (HCC) in a multicenter randomized trial. METHODS AND MATERIALS: Patients were included if they were eligible for TACE. They could also be recruited if they required treatment prior to liver transplantation. A maximum of four TACE-DEB procedures and ablation after incomplete TACE-DEB were both allowed. SBRT was delivered in six fractions of 8-9Gy. Primary end point was time to progression (TTP). Secondary endpoints were local control (LC), overall survival (OS), response rate (RR), toxicity, and quality of life (QoL). The calculated sample size was 100 patients. RESULTS: Between May 2015 and April 2020, 30 patients were randomized to the study. Due to slow accrual the trial was closed prematurely. Two patients in the SBRT arm were considered ineligible leaving 16 patients in the TACE-DEB arm and 12 in the SBRT arm. Median follow-up was 28.1 months. Median TTP was 12 months for TACEDEB and 19 months for SBRT (p=0.15). Median LC was 12 months for TACE-DEB and >40 months (not reached) for SBRT (p=0.075). Median OS was 36.8 months for TACEDEB and 44.1 months for SBRT (p=0.36). A post-hoc analysis showed 100% for SBRT 1- and 2-year LC, and 54.4% and 43.6% for TACE-DEB (p=0.019). Both treatments resulted in RR>80%. Three episodes of possibly related toxicity grade ≥3 were observed after TACE-DEB. No episodes were observed after SBRT. QoL remained stable after both treatment arms. CONCLUSIONS: In this trial, TTP after TACE-DEB was not significantly improved by SBRT, while SBRT showed higher local antitumoral activity than TACE-DEB, without detrimental effects on OS, toxicity and QoL. To overcome poor accrual in randomized trials that include SBRT, and to generate evidence for including SBRT in treatment guidelines, international cooperation is needed.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Radiocirurgia , Humanos , Radiocirurgia/efeitos adversos , Carcinoma Hepatocelular/radioterapia , Qualidade de Vida , Neoplasias Hepáticas/radioterapia
10.
Exp Hematol ; 121: 6-11, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36764598

RESUMO

Immunologic memory is a feature typically ascribed to the adaptive arm of the immune system. However, recent studies have demonstrated that hematopoietic stem cells (HSCs) and innate immune cells such as monocytes and macrophages can gain epigenetic signatures to enhance their response in the context of reinfection. This suggests the presence of long-term memory, a phenomenon referred to as trained immunity. Trained immunity in HSCs can occur via changes in the epigenetic landscape and enhanced chromatin accessibility in lineage-specific genes, as well as through metabolic alterations. These changes can lead to a skewing in lineage bias, particularly enhanced myelopoiesis and the generation of epigenetically modified innate immune cells that provide better protection against pathogens on secondary infection. Here, we summarize recent advancements in trained immunity and epigenetic memory formation in HSCs and self-renewing alveolar macrophages, which was the focus of the Spring 2022 International Society for Experimental Hematology (ISEH) webinar.


Assuntos
Imunidade Inata , Imunidade Treinada , Imunidade Inata/genética , Memória Epigenética , Macrófagos , Memória Imunológica/genética
11.
J Exp Clin Cancer Res ; 41(1): 340, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36482393

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is an aggressive hematological cancer resulting from uncontrolled proliferation of differentiation-blocked myeloid cells. Seventy percent of AML patients are currently not cured with available treatments, highlighting the need of novel therapeutic strategies. A promising target in AML is the mammalian target of rapamycin complex 1 (mTORC1). Clinical inhibition of mTORC1 is limited by its reactivation through compensatory and regulatory feedback loops. Here, we explored a strategy to curtail these drawbacks through inhibition of an important effector of the mTORC1signaling pathway, the eukaryotic initiation factor 4A (eIF4A). METHODS: We tested the anti-leukemic effect of a potent and specific eIF4A inhibitor (eIF4Ai), CR-1-31-B, in combination with cytosine arabinoside (araC) or the BCL2 inhibitor venetoclax. We utilized the MOLM-14 human AML cell line to model chemoresistant disease both in vitro and in vivo. In eIF4Ai-treated cells, we assessed for changes in survival, apoptotic priming, de novo protein synthesis, targeted intracellular metabolite content, bioenergetic profile, mitochondrial reactive oxygen species (mtROS) and mitochondrial membrane potential (MMP). RESULTS: eIF4Ai exhibits anti-leukemia activity in vivo while sparing non-malignant myeloid cells. In vitro, eIF4Ai synergizes with two therapeutic agents in AML, araC and venetoclax. EIF4Ai reduces mitochondrial membrane potential (MMP) and the rate of ATP synthesis from mitochondrial respiration and glycolysis. Furthermore, eIF4i enhanced apoptotic priming while reducing the expression levels of the antiapoptotic factors BCL2, BCL-XL and MCL1. Concomitantly, eIF4Ai decreases intracellular levels of specific metabolic intermediates of the tricarboxylic acid cycle (TCA cycle) and glucose metabolism, while enhancing mtROS. In vitro redox stress contributes to eIF4Ai cytotoxicity, as treatment with a ROS scavenger partially rescued the viability of eIF4A inhibition. CONCLUSIONS: We discovered that chemoresistant MOLM-14 cells rely on eIF4A-dependent cap translation for survival in vitro and in vivo. EIF4A drives an intrinsic metabolic program sustaining bioenergetic and redox homeostasis and regulates the expression of anti-apoptotic proteins. Overall, our work suggests that eIF4A-dependent cap translation contributes to adaptive processes involved in resistance to relevant therapeutic agents in AML.


Assuntos
Antineoplásicos , Citarabina , Fator de Iniciação 4A em Eucariotos , Leucemia Mieloide Aguda , Humanos , Citarabina/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2 , Linhagem Celular Tumoral , Fator de Iniciação 4A em Eucariotos/antagonistas & inibidores , Antineoplásicos/farmacologia
12.
Surgery ; 172(6): 1606-1613, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35989132

RESUMO

BACKGROUND: The patients with unresectable perihilar cholangiocarcinoma require biliary drainage to relieve symptoms and allow for palliative systemic chemotherapy. The aim of this study was to establish the success, complication, and mortality rates of the initial biliary drainage in patients with unresectable perihilar cholangiocarcinoma at presentation. METHODS: In this retrospective multicenter study, patients with unresectable perihilar cholangiocarcinoma who underwent initial endoscopic or percutaneous transhepatic biliary drainage between 2002 and 2014 were included. The success of drainage was defined as a successful biliary stent or drain placement, no unscheduled reintervention within 14 days, and serum bilirubin levels <50 µmol/L (ie, 2.9 mg/dL) or a >50% decrease in serum bilirubin after 14 days. Severe complications, and 90-day mortality were recorded. RESULTS: Included were 186 patients: 161 (87%) underwent initial endoscopic biliary drainage and 25 (13%) underwent initial percutaneous transhepatic biliary drainage. The success of initial drainage was observed in 73 patients (45%) after endoscopic biliary drainage and 6 (24%) after percutaneous transhepatic biliary drainage. The reasons for an unsuccessful initial drainage were: the failure to place a drain or stent in 39 patients (21%), an unplanned reintervention within 14 days in 52 patients (28%), and the bilirubin level >50 µmol/L (or not halved) after 14 days of initial drainage in 16 patients (9%). Severe drainage-related complications occurred in 19 patients (12%) after endoscopic biliary drainage and in 3 (12%) after percutaneous transhepatic biliary drainage. Overall, 66 patients (36%) died within 90 days after initial biliary drainage. CONCLUSION: Initial biliary drainage in patients with unresectable perihilar cholangiocarcinoma had a success rate of 45% and a 90-day mortality rate of 36%. Future studies for patients with perihilar cholangiocarcinoma should focus on improving biliary drainage.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Humanos , Tumor de Klatskin/cirurgia , Tumor de Klatskin/complicações , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/complicações , Colangiocarcinoma/cirurgia , Drenagem/efeitos adversos , Stents/efeitos adversos , Estudos Retrospectivos , Ductos Biliares Intra-Hepáticos/patologia , Bilirrubina , Resultado do Tratamento
13.
Front Pharmacol ; 13: 852143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795568

RESUMO

Multi-omic approaches offer an unprecedented overview of the development, plasticity, and resistance of cancer. However, the translation from anti-cancer compounds identified in vitro to clinically active drugs have a notoriously low success rate. Here, we review how technical advances in cell culture, robotics, computational biology, and development of reporter systems have transformed drug discovery, enabling screening approaches tailored to clinically relevant functional readouts (e.g., bypassing drug resistance). Illustrating with selected examples of "success stories," we describe the process of phenotype-based high-throughput drug screening to target malignant cells or the immune system. Second, we describe computational approaches that link transcriptomic profiling of cancers with existing pharmaceutical compounds to accelerate drug repurposing. Finally, we review how CRISPR-based screening can be applied for the discovery of mechanisms of drug resistance and sensitization. Overall, we explore how the complementary strengths of each of these approaches allow them to transform the paradigm of pre-clinical drug development.

14.
Blood Adv ; 6(17): 5072-5084, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35793392

RESUMO

Genome-wide CRISPR screens have been extremely useful in identifying therapeutic targets in diverse cancers by defining genes that are essential for malignant growth. However, most CRISPR screens were performed in vitro and thus cannot identify genes that are essential for interactions with the microenvironment in vivo. Here, we report genome-wide CRISPR screens in 2 in vivo murine models of acute myeloid leukemia (AML) driven by the KMT2A/MLLT3 fusion or by the constitutive coexpression of Hoxa9 and Meis1. Secondary validation using a focused library identified 72 genes specifically essential for leukemic growth in vivo, including components of the major histocompatibility complex class I complex, Cd47, complement receptor Cr1l, and the ß-4-galactosylation pathway. Importantly, several of these in vivo-specific hits have a prognostic effect or are inferred to be master regulators of protein activity in human AML cases. For instance, we identified Fermt3, a master regulator of integrin signaling, as having in vivo-specific dependency with high prognostic relevance. Overall, we show an experimental and computational pipeline for genome-wide functional screens in vivo in AML and provide a genome-wide resource of essential drivers of leukemic growth in vivo.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Leucemia Mieloide Aguda , Animais , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Proteína Meis1/genética , Proteína Meis1/metabolismo , Transdução de Sinais , Microambiente Tumoral/genética
15.
Exp Hematol ; 111: 25-31, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487293

RESUMO

Post-transcriptional RNA modifications determine RNA fate by influencing numerous processes such as translation, decay and localization. One of the most abundant RNA modifications is N6-methyladenoside (m6A), which has been shown to be important in healthy as well as malignant hematopoiesis. Several proteins representing key players in m6A RNA biology, such as m6A writers, erasers and readers, were recently reported to be essential for hematopoietic stem cell (HSC) function. In leukemia, expression of m6A regulators has been shown to be increased, opening up potential opportunities for therapeutic exploitation by targeting them in blood malignancies. These recent discoveries were the focus of the Fall 2021 International Society for Experimental Hematology New Investigators webinar. We review here the latest findings in the field of mRNA modifications in normal and malignant hematopoiesis and how this might open up novel therapeutic options.


Assuntos
Hematopoese , Leucemia , Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia/genética , RNA/metabolismo , Processamento Pós-Transcricional do RNA
16.
J Digit Imaging ; 35(2): 127-136, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35088185

RESUMO

Treatment planning of gastrointestinal stromal tumors (GISTs) includes distinguishing GISTs from other intra-abdominal tumors and GISTs' molecular analysis. The aim of this study was to evaluate radiomics for distinguishing GISTs from other intra-abdominal tumors, and in GISTs, predict the c-KIT, PDGFRA, BRAF mutational status, and mitotic index (MI). Patients diagnosed at the Erasmus MC between 2004 and 2017, with GIST or non-GIST intra-abdominal tumors and a contrast-enhanced venous-phase CT, were retrospectively included. Tumors were segmented, from which 564 image features were extracted. Prediction models were constructed using a combination of machine learning approaches. The evaluation was performed in a 100 × random-split cross-validation. Model performance was compared to that of three radiologists. One hundred twenty-five GISTs and 122 non-GISTs were included. The GIST vs. non-GIST radiomics model had a mean area under the curve (AUC) of 0.77. Three radiologists had an AUC of 0.69, 0.76, and 0.84, respectively. The radiomics model had an AUC of 0.52 for c-KIT, 0.56 for c-KIT exon 11, and 0.52 for the MI. The numbers of PDGFRA, BRAF, and other c-KIT mutations were too low for analysis. Our radiomics model was able to distinguish GISTs from non-GISTs with a performance similar to three radiologists, but less observer dependent. Therefore, it may aid in the early diagnosis of GIST, facilitating rapid referral to specialized treatment centers. As the model was not able to predict any genetic or molecular features, it cannot aid in treatment planning yet.


Assuntos
Neoplasias Abdominais , Tumores do Estroma Gastrointestinal , Diagnóstico Diferencial , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-kit/genética , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
17.
Blood ; 139(4): 502-522, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34610101

RESUMO

Proton export is often considered a detoxifying process in animal cells, with monocarboxylate symporters coexporting excessive lactate and protons during glycolysis or the Warburg effect. We report a novel mechanism by which lactate/H+ export is sufficient to induce cell growth. Increased intracellular pH selectively activates catalysis by key metabolic gatekeeper enzymes HK1/PKM2/G6PDH, thereby enhancing glycolytic and pentose phosphate pathway carbon flux. The result is increased nucleotide levels, NADPH/NADP+ ratio, and cell proliferation. Simply increasing the lactate/proton symporter monocarboxylate transporter 4 (MCT4) or the sodium-proton antiporter NHE1 was sufficient to increase intracellular pH and give normal hematopoietic cells a significant competitive growth advantage in vivo. This process does not require additional cytokine triggers and is exploited in malignancy, where leukemogenic mutations epigenetically increase MCT4. Inhibiting MCT4 decreased intracellular pH and carbon flux and eliminated acute myeloid leukemia-initiating cells in mice without cytotoxic chemotherapy. Intracellular alkalization is a primitive mechanism by which proton partitioning can directly reprogram carbon metabolism for cell growth.


Assuntos
Carbono/metabolismo , Proliferação de Células , Ácido Láctico/metabolismo , Leucemia Mieloide Aguda/metabolismo , Animais , Transformação Celular Neoplásica/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos C57BL , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Via de Pentose Fosfato , Prótons , Células Tumorais Cultivadas
18.
Comput Methods Programs Biomed ; 214: 106537, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34879326

RESUMO

BACKGROUND AND OBJECTIVE: Longitudinal analysis of patient-reported outcome (PRO) data remains challenging, as no standardization of statistical methods has been proposed, making comparison of PRO results between clinical trials difficult. In this context, the time to deterioration approach has recently been proposed and is regularly used as a modality of longitudinal PRO analysis in oncology. METHODS: Two new SAS macro programs were developed, %TTD and %TUDD, which implement longitudinal analysis of PRO data according to the time to deterioration approach. These programs implement the recommended deterioration definitions. We described the programs with their different functionalities. RESULTS: The %TTD macro calculates the time to first or transient deterioration, and the %TUDD macro calculates the time until definitive deterioration. These macros allow to obtain the survival variables from the time to deterioration approach. We illustrate our programs by presenting different applications on the randomized phase II AFUGEM GERCOR clinical trial. CONCLUSION: The implementation of the deterioration definitions in SAS software allows the dissemination of this approach, in order to move toward the goal of standardization of longitudinal PRO analysis in oncology clinical trials.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Oncologia , Medidas de Resultados Relatados pelo Paciente , Software
19.
Clin Exp Metastasis ; 38(5): 483-494, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34533669

RESUMO

Histopathological growth patterns (HGPs) are independent prognosticators for colorectal liver metastases (CRLM). Currently, HGPs are determined postoperatively. In this study, we evaluated radiomics for preoperative prediction of HGPs on computed tomography (CT), and its robustness to segmentation and acquisition variations. Patients with pure HGPs [i.e. 100% desmoplastic (dHGP) or 100% replacement (rHGP)] and a CT-scan who were surgically treated at the Erasmus MC between 2003-2015 were included retrospectively. Each lesion was segmented by three clinicians and a convolutional neural network (CNN). A prediction model was created using 564 radiomics features and a combination of machine learning approaches by training on the clinician's and testing on the unseen CNN segmentations. The intra-class correlation coefficient (ICC) was used to select features robust to segmentation variations; ComBat was used to harmonize for acquisition variations. Evaluation was performed through a 100 × random-split cross-validation. The study included 93 CRLM in 76 patients (48% dHGP; 52% rHGP). Despite substantial differences between the segmentations of the three clinicians and the CNN, the radiomics model had a mean area under the curve of 0.69. ICC-based feature selection or ComBat yielded no improvement. Concluding, the combination of a CNN for segmentation and radiomics for classification has potential for automatically distinguishing dHGPs from rHGP, and is robust to segmentation and acquisition variations. Pending further optimization, including extension to mixed HGPs, our model may serve as a preoperative addition to postoperative HGP assessment, enabling further exploitation of HGPs as a biomarker.


Assuntos
Neoplasias Colorretais/patologia , Aprendizado Profundo , Neoplasias Hepáticas/secundário , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Projetos Piloto
20.
Cancers (Basel) ; 13(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34439146

RESUMO

BACKGROUND: In unresectable pCCA, the standard of care is palliative chemotherapy. We investigated the feasibility and safety of adding stereotactic body radiation therapy (SBRT) after chemotherapy. METHODS: Patients with unresectable pCCA, stage T1-T4N0-N1M0, ECOG 0-1, having finished 6-8 cycles of cisplatin and gemcitabine without disease progression were eligible. SBRT was planned in 15 fractions of 3.0-4.5 Gy. The primary endpoints were feasibility (defined as completing SBRT as planned) and toxicity, evaluated within 3 months after SBRT (CTCAE v4.03). A conventional "3 + 3" design was used, corresponding to a sample size of 6 patients. Dose-limiting toxicity (DLT) was defined as grade ≥ 4 hepatobiliary or grade ≥ 3 gastrointestinal toxicity. The secondary endpoints, measured from the start of radiotherapy, were local control, progression-free survival, overall survival, and quality of life (QoL). ClinicalTrials.gov identifier: NCT03307538. RESULTS: Six patients were enrolled between November 2017 and March 2020. SBRT was delivered as planned. All patients were treated with 60Gy (15 × 4.0Gy). No SBRT-related DLT was observed. The most common grade ≥ 3 toxicity was cholangitis (n = 5). The median follow-up was 14 months. The 12-month local control rate was 80%. We observed no substantial changes in QoL. CONCLUSION: In patients with unresectable pCCA with stable disease after palliative chemotherapy, adding SBRT is feasible and safe. The observed local control merits an additional evaluation of effectiveness.

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