Eglerisine, a Novel Sesquiterpenoid Tropolone from Dulacia egleri with Antiproliferative Effect against an Acute Myeloid Leukemia Lineage

Planta Medica ◽  
2019 ◽  
Vol 86 (01) ◽  
pp. 55-60 ◽  
Author(s):  
Leice M. R. de Novais ◽  
Luiz F. Ferreira ◽  
Paulo T. de Sousa ◽  
Tereza A. N. Ribeiro ◽  
Marcos J. Jacinto ◽  
...  

AbstractChemical investigation of the stems of Dulacia egleri resulted in the isolation of eglerisine (1), a compound with a rare sesquiterpenoid tropolone skeleton. Its structure was determined by analysis of spectrometric and spectroscopic data, including HRESIMS, 1D, and 2D NMR. The antiproliferative effects of eglerisine were tested in human leukemia lineages. In the Kasumi-1 lineage, an acute myeloid leukemia cell line, eglerisine reduced cell metabolism, as determined by the resazurin assay. Eglerisine did not induce cell death by either apoptotic or necrotic mechanisms. However, a reduction of the absolute number of cells was observed. Eglerisine induced cell cycle arrest after 72 h of treatment by phosphorylation of H2AX histone, reducing the S phase and increasing the G2 phase of the cell cycle.

Blood ◽  
1993 ◽  
Vol 82 (4) ◽  
pp. 1151-1158 ◽  
Author(s):  
PS Crosier ◽  
ST Ricciardi ◽  
LR Hall ◽  
MR Vitas ◽  
SC Clark ◽  
...  

Abstract Because mutations in receptor tyrosine kinases may contribute to cellular transformation, studies were undertaken to examine c-kit in human leukemia. Isoforms of c-kit have been characterized in the human megakaryoblastic leukemia cell line M-07. Deletion of the four amino acids Gly-Asn-Asn-Lys in the extracellular domain represents an alternatively spliced isoform that has been shown by others, in mice, to be associated with constitutive receptor autophosphorylation (Reith et al, EMBO J 10:2451, 1991). Additional isoforms differ in the inclusion or exclusion of a serine residue in the interkinase domain, a region that contains the binding site for phosphatidylinositol 3- kinase. By RNase protection analysis, we have shown coexpression of the Gly-Asn-Asn-Lys+ and Gly-Asn-Asn-Lys- isoforms, with dominance of the Gly-Asn-Asn-Lys- transcript, in normal human bone marrow, normal melanocytes, a range of tumor cell lines, and the blasts of 23 patients with acute myeloid leukemia. Analysis of transcripts for the Ser+ and Ser- isoforms also showed coexpression in all normal and leukemic cells examined. The ratios of isoform expression for both the Gly-Asn-Asn-Lys and Ser variants were relatively constant, providing no evidence in the tumors examined that upregulation of one isoform contributes to the neoplastic process.


Blood ◽  
1993 ◽  
Vol 82 (4) ◽  
pp. 1151-1158 ◽  
Author(s):  
PS Crosier ◽  
ST Ricciardi ◽  
LR Hall ◽  
MR Vitas ◽  
SC Clark ◽  
...  

Because mutations in receptor tyrosine kinases may contribute to cellular transformation, studies were undertaken to examine c-kit in human leukemia. Isoforms of c-kit have been characterized in the human megakaryoblastic leukemia cell line M-07. Deletion of the four amino acids Gly-Asn-Asn-Lys in the extracellular domain represents an alternatively spliced isoform that has been shown by others, in mice, to be associated with constitutive receptor autophosphorylation (Reith et al, EMBO J 10:2451, 1991). Additional isoforms differ in the inclusion or exclusion of a serine residue in the interkinase domain, a region that contains the binding site for phosphatidylinositol 3- kinase. By RNase protection analysis, we have shown coexpression of the Gly-Asn-Asn-Lys+ and Gly-Asn-Asn-Lys- isoforms, with dominance of the Gly-Asn-Asn-Lys- transcript, in normal human bone marrow, normal melanocytes, a range of tumor cell lines, and the blasts of 23 patients with acute myeloid leukemia. Analysis of transcripts for the Ser+ and Ser- isoforms also showed coexpression in all normal and leukemic cells examined. The ratios of isoform expression for both the Gly-Asn-Asn-Lys and Ser variants were relatively constant, providing no evidence in the tumors examined that upregulation of one isoform contributes to the neoplastic process.


2011 ◽  
Author(s):  
Michael Roberts ◽  
David Bittner ◽  
Sarah Brnich ◽  
Bryan Conner ◽  
Carla Cox ◽  
...  

2005 ◽  
Vol 79 (9) ◽  
pp. 5249-5258 ◽  
Author(s):  
Eric van den Akker ◽  
Yolanda Vankan-Berkhoudt ◽  
Peter J. M. Valk ◽  
Bob Löwenberg ◽  
Ruud Delwel

ABSTRACT The leukemia and lymphoma disease locus Evi12 was mapped to the noncoding region of a novel gene, Gnn (named for Grp94 neighboring nucleotidase), that is located immediately upstream of the Grp94/Tra1 gene on mouse chromosome 10. The Gnn gene is conserved in mice and humans. Expression of fusion constructs between GFP and Gnn cDNA isoforms in HEK-293 cells showed that Gnn proteins are located mainly in the cytoplasm. Immunoblotting experiments demonstrated the presence of multiple Gnn protein isoforms in most organs, with the lowest levels of expression of the protein detected in bone marrow and spleen. The Evi12-containing leukemia cell line NFS107 showed high levels of expression of a ∼150-kDa Gnn isoform (Gnn107) that was not observed in control cell lines. Overexpression may be due to the viral insertion in Evi12. The Gnn107 protein is probably encoded by a Gnn cDNA isoform that is expressed exclusively in NFS107 cells and that includes sequences of TU12B1-TY, a putative protein with homology to 5′-nucleotidase enzymes. Interestingly, using Affymetrix gene expression data of a cohort of 285 patients with acute myeloid leukemia (AML), we found that GNN/TU12B1-TY expression was specifically increased in two AML clusters. One cluster consisted of all AML patients with a t(8;21) translocation, and the second cluster consisted of AML patients with a normal karyotype carrying a FLT3 internal tandem duplication. These findings suggest that we identified a novel proto-oncogene that may be causally linked to certain types of human leukemia.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3786-3786
Author(s):  
Ting Liu ◽  
Dragana Jankovic ◽  
Laurent Brault ◽  
Sabine Ehret ◽  
Vincenzo Rossi ◽  
...  

Abstract Expression of meningioma 1 (MN1) has been proposed to be a negative prognostic marker in adult acute myeloid leukemia (AML). In pediatric leukemia, we found overexpression of MN1 in 53 of 88 cases: whereas no MN1 expression was detected in T-cell acute lymphoblastic leukemia (T-ALL), significant amounts of MN1 were found in immature B-cell ALL and most cases of infant leukemia. Interestingly, 17 of 19 cases harboring fusion genes involving the mixed-lineage leukemia (MLL-X) gene showed elevated MN1 expression. Lentiviral siRNA mediated MN1 knock-down resulted in cell cycle arrest and impaired clonogenic growth of 3 MLL-X-positive human leukemia cell lines overexpressing MN1 (THP-1, RS4;11, MOLM-13). In a mouse model of MLL-ENL-induced leukemia we found MN1 to be overexpressed as a consequence of provirus integration. Strikingly co-expression of MN1 with MLL-ENL resulted in significantly reduced latency for induction of an AML phenotype in mice suggesting functional cooperation. Immunophenotyping and secondary transplant experiments suggested that MN1 overexpression seems to expand the L-GMP cell population targeted by the MLL-ENL fusion. Gene expression profiling allowed defining a number of potential MN1 hematopoietic targets. Upregulation of CD34, FLT3, HLF, or DLK1 was validated in bone marrow transiently overexpressing MN1, in MN1-induced mouse acute myeloid leukemia, as well as in pediatric leukemias with elevated MN1 levels. Our work shows that MN1 is overexpressed in a significant fraction of pediatric acute leukemia, is essential for growth of leukemic cells, and that MN1 can act as a cooperating oncogene with MLL-ENL most probably through modification of a distinct gene expression program that leads to expansion of a leukemic progenitor population targeted by MLL-fusion genes.


Haematologica ◽  
2020 ◽  
Author(s):  
Bing Z. Carter ◽  
Po Yee Mak ◽  
Wenjing Tao ◽  
Marc Warmoes ◽  
Philip L. Lorenzi ◽  
...  

MCL-1 and BCL-2 are both frequently overexpressed in acute myeloid leukemia and critical for the survival of acute myeloid leukemia cells and acute myeloid leukemia stem cells. MCL-1 is a key factor in venetoclax resistance. Using genetic and pharmacological approaches, we discovered that MCL-1 regulates leukemia cell bioenergetics and carbohydrate metabolisms, including the TCA cycle, glycolysis and pentose phosphate pathway and modulates cell adhesion proteins and leukemia-stromal interactions. Inhibition of MCL-1 sensitizes to BCL-2 inhibition in acute myeloid leukemia cells and acute myeloid leukemia stem/progenitor cells, including those with intrinsic and acquired resistance to venetoclax through cooperative release of pro-apoptotic BIM, BAX, and BAK from binding to anti-apoptotic BCL-2 proteins and inhibition of cell metabolism and key stromal microenvironmental mechanisms. The combined inhibition of MCL-1 by MCL-1 inhibitor AZD5991 or CDK9 inhibitor AZD4573 and BCL-2 by venetoclax greatly extended survival of mice bearing patient-derived xenografts established from an acute myeloid leukemia patient who acquired resistance to venetoclax/decitabine. These results demonstrate that co-targeting MCL-1 and BCL-2 improves the efficacy of and overcomes preexisting and acquired resistance to BCL-2 inhibition. Activation of metabolomic pathways and leukemia-stroma interactions are newly discovered functions of MCL-1 in acute myeloid leukemia, which are independent from canonical regulation of apoptosis by MCL-1. Our data provide new mechanisms of synergy and rationale for co-targeting MCL-1 and BCL-2 clinically in patients with acute myeloid leukemia and potentially other cancers.


Sign in / Sign up

Export Citation Format

Share Document