scholarly journals Requirement of DNMT1 to orchestrate epigenomic reprogramming for NPM-ALK–driven lymphomagenesis

2020 ◽  
Vol 4 (2) ◽  
pp. e202000794
Author(s):  
Elisa Redl ◽  
Raheleh Sheibani-Tezerji ◽  
Crhistian de Jesus Cardona ◽  
Patricia Hamminger ◽  
Gerald Timelthaler ◽  
...  

Malignant transformation depends on genetic and epigenetic events that result in a burst of deregulated gene expression and chromatin changes. To dissect the sequence of events in this process, we used a T-cell–specific lymphoma model based on the human oncogenic nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) translocation. We find that transformation of T cells shifts thymic cell populations to an undifferentiated immunophenotype, which occurs only after a period of latency, accompanied by induction of the MYC-NOTCH1 axis and deregulation of key epigenetic enzymes. We discover aberrant DNA methylation patterns, overlapping with regulatory regions, plus a high degree of epigenetic heterogeneity between individual tumors. In addition, ALK-positive tumors show a loss of associated methylation patterns of neighboring CpG sites. Notably, deletion of the maintenance DNA methyltransferase DNMT1 completely abrogates lymphomagenesis in this model, despite oncogenic signaling through NPM-ALK, suggesting that faithful maintenance of tumor-specific methylation through DNMT1 is essential for sustained proliferation and tumorigenesis.

2020 ◽  
Author(s):  
Elisa Redl ◽  
Raheleh Sheibani-Tezerji ◽  
Patricia Hamminger ◽  
Gerald Timelthaler ◽  
Melanie Rosalia Hassler ◽  
...  

ABSTRACTMalignant transformation depends on genetic and epigenetic events that result in a burst of deregulated gene expression and chromatin changes. To dissect the sequence of events in this process, we used a T cell-specific lymphoma model based on the human oncogenic NPM-ALK translocation. We find that transformation of T cells shifts thymic cell populations to an undifferentiated immunophenotype, which occurs only after a period of latency, accompanied by induction of the MYC-NOTCH1 axis and deregulation of key epigenetic enzymes. We discover aberrant DNA methylation patterns, overlapping with regulatory regions, plus a high degree of epigenetic heterogeneity between individual tumors. In addition, ALK positive tumors show a loss of collaborative methylation patterns of neighboring CpG sites. Notably, deletion of the maintenance DNA methyltransferase DNMT1 completely abrogates lymphomagenesis in this model, despite oncogenic signaling through NPM-ALK, suggesting that faithful maintenance of tumor-specific methylation through DNMT1 is essential for sustained proliferation and tumorigenesis.STATEMENT OF SIGNIFICANCEEpigenetic alterations are causally involved in tumorigenesis. Here we show that induction of a single human oncogene in murine T cells induces specific deregulation of epigenetic enzymes resulting in epigenomic alterations similar to human tumors. Our findings are of broader implication to understand how epigenomic processes are shaped by oncogene induced transformation.


2003 ◽  
Vol 81 (3) ◽  
pp. 197-208 ◽  
Author(s):  
Giuseppe Zardo ◽  
Anna Reale ◽  
Giovanna De Matteis ◽  
Serena Buontempo ◽  
Paola Caiafa

The aberrant DNA methylation of promoter regions of housekeeping genes leads to gene silencing. Additional epigenetic events, such as histone methylation and acetylation, also play a very important role in the definitive repression of gene expression by DNA methylation. If the aberrant DNA methylation of promoter regions is the starting or the secondary event leading to the gene silencing is still debated. Mechanisms controlling DNA methylation patterns do exist although they have not been ultimately proven. Our data suggest that poly(ADP-ribosyl)ation might be part of this control mechanism. Thus an additional epigenetic modification seems to be involved in maintaining tissue and cell-type methylation patterns that when formed during embryo development, have to be rigorously conserved in adult organisms.Key words: DNA methylation, chromatin, poly(ADP-ribosyl)ation.


2021 ◽  
Vol 14 (4) ◽  
pp. e240295
Author(s):  
Hironari Matsuda ◽  
Munechika Hara ◽  
Shin-Ichiro Iwakami ◽  
Kazuhisa Takahashi

This report concerns a patient with skeletal muscle metastases due to lung adenocarcinoma harbouring an echinoderm microtubule-associated protein-like-4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement, who was successfully treated with lorlatinib after resistance to alectinib. A right lower lobectomy based on a diagnosis of lung adenocarcinoma was performed on a 77-year-old Japanese woman. After 7 months of surgical resection, a mass in the right calf was observed. A fine-needle aspiration biopsy from the mass was performed and the mass was diagnosed as metastatic adenocarcinoma harbouring EML4-ALK rearrangement. Alectinib was administered for 10 months. Then, administration of lorlatinib, an ALK tyrosine kinase inhibitor classified as third generation, was initiated after resistance to treatment with alectinib. After starting treatment with lorlatinib, the gastrocnemius tumour diminished and has maintained a stable condition. Our case suggests that EML4-ALK positive lung adenocarcinoma is treatable with lorlatinib after resistance to treatment with alectinib.


Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 253
Author(s):  
Federica Lovisa ◽  
Anna Garbin ◽  
Sara Crotti ◽  
Piero Di Battista ◽  
Ilaria Gallingani ◽  
...  

Over the past 15 years, several biological and pathological characteristics proved their significance in pediatric anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALCL) prognostic stratification. However, the identification of new non-invasive disease biomarkers, relying on the most important disease mechanisms, is still necessary. In recent years, plasmatic circulating small extracellular vesicles (S-EVs) gathered great importance both as stable biomarker carriers and active players in tumorigenesis. In the present work, we performed a comprehensive study on the proteomic composition of plasmatic S-EVs of pediatric ALCL patients compared to healthy donors (HDs). By using a mass spectrometry-based proteomics approach, we identified 50 proteins significantly overrepresented in S-EVs of ALCL patients. Gene Ontology enrichment analysis disclosed cellular components and molecular functions connected with S-EV origin and vesicular trafficking, whereas cell adhesion, glycosaminoglycan metabolic process, extracellular matrix organization, collagen fibril organization and acute phase response were the most enriched biological processes. Of importance, consistently with the presence of nucleophosmin (NPM)-ALK fusion protein in ALCL cells, a topological enrichment analysis based on Reactome- and Kyoto Encyclopedia of Genes and Genomes (KEGG)-derived networks highlighted a dramatic increase in proteins of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway in ALCL S-EVs, which included heat shock protein 90-kDa isoform alpha 1 (HSP90AA1), osteopontin (SPP1/OPN) and tenascin C (TNC). These results were validated by Western blotting analysis on a panel of ALCL and HD cases. Further research is warranted to better define the role of these S-EV proteins as diagnostic and, possibly, prognostic parameters at diagnosis and for ALCL disease monitoring.


Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1966
Author(s):  
Cheng-Hao Chuang ◽  
Hsiao-Ling Chen ◽  
Hsiu-Mei Chang ◽  
Yu-Chen Tsai ◽  
Kuan-Li Wu ◽  
...  

Several anaplastic lymphoma kinase inhibitors (ALKIs) have demonstrated excellent efficacy on overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and also better adverse effect (AE) profiles compared to cytotoxic chemotherapy in advanced stage anaplastic lymphoma kinase (ALK) rearrangement-positive non-small cell lung cancer (NSCLC) in phase III randomized clinical trials (RCTs). We conducted this systematic review and network meta-analysis to provide a ranking of ALKIs for treatment-naïve ALK-positive patients in terms of PFS, ORR, and AEs. In addition, a sub-group analysis of treatment benefits in patients with baseline brain metastasis was also conducted. Contrast-based analysis was performed for multiple treatment comparisons with the restricted maximum likelihood approach. Treatment rank was estimated using the surface under the cumulative ranking curve (SUCRA), as well as the probability of being the best (Prbest) reference. All next-generation ALKIs were superior to crizotinib in PFS but lorlatinib and brigatinib had increased AEs. The probability of lorlatinib being ranked first among all treatment arms was highest (SUCRA = 93.3%, Prbest = 71.8%), although there were no significant differences in pairwise comparisons with high- (600 mg twice daily) and low- (300 mg twice daily) dose alectinib. In subgroup analysis of patients with baseline brain metastasis, low-dose alectinib had the best PFS (SUCRA = 87.3%, Prbest = 74.9%). Lorlatinib was associated with the best ranking for ORR (SUCRA = 90.3%, Prbest = 71.3%), although there were no significant differences in pairwise comparisons with the other ALKIs. In addition, low-dose alectinib had the best safety performance (SUCRA = 99.4%, Prbest = 97.9%). Lorlatinib and low-dose alectinib had the best PFS and ORR in the overall population and baseline brain metastasis subgroup, respectively. Low-dose alectinib had the lowest AE risk among the available ALKIs. Further head-to-head large-scale phase III RCTs are needed to verify our conclusions.


2020 ◽  
Vol 26 (8) ◽  
pp. 2031-2033
Author(s):  
Nilay Sengul Samanci ◽  
Emir Celik ◽  
Burak Akovalı ◽  
Sait Sager ◽  
Fuat Hulusi Demirelli

Introduction Ceritinib is a selective second-generation ALK inhibitor that is highly sensitive to echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) molecule. Case report In this paper, we report a 68-year-old female that was diagnosed with stage 4 ALK-positive non-small cell lung cancer (NSCLC). Management and outcome: She was treated with crizotinib first-line, cisplatin and gemcitabine as second-line. And for third-line, ceritinib was started. She had complete response over 3.5 years under ceritinib treatment. And she is still receiving ceritinib with no adverse event. Discussion Cases achieving complete response with ceritinib treatment are rare. In this paper, we aimed to emphasize the complete response in stage 4 NSCLC in an elderly patient.


2004 ◽  
Vol 24 (4) ◽  
pp. 1640-1648 ◽  
Author(s):  
F. Gaudet ◽  
W. M. Rideout ◽  
A. Meissner ◽  
J. Dausman ◽  
H. Leonhardt ◽  
...  

ABSTRACT The methylation of intracisternal A-type particle (IAP) sequences is maintained during mouse embryogenesis. Methylation suppresses IAP expression and the potential for mutagenesis by retrotransposition, but it is not clear how methylation of these elements is maintained during the embryonic stages when the bulk of the genome is being demethylated. It has been suggested that the high levels of DNA methyltransferase-1 (Dnmt1) present during cleavage could be important for keeping IAPs methylated. To test this hypothesis, we combined mutant alleles of Dnmt1 with an agouti allele (Aiapy ), which provided a coat color readout for the methylation status of the IAP insertion in the agouti locus. We found that reduction in Dnmt1 levels directly impacted methylation at this locus, leading to stable transcriptional activation of the agouti gene in the adult. Specifically, the short maternal Dnmt1 protein was important in maintaining methylation at the Aiapy locus in cleavage embryos, whereas the longer Dnmt1 isoform found in somatic cells was important in maintaining IAP methylation during the postimplantation stage. These results underscore the importance of maintaining proper maintenance of methylation patterns during gestation and suggest that interference with this process may stably affect gene expression patterns in the adult and may have profound phenotypic consequences.


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