tretinoin and Leukemia--Megakaryoblastic--Acute

There is no established effective treatment for patients with t(1;22)(p13;q13) acute megakaryoblastic leukemia (AMKL) and hepatic fibrosis.. Here we report the outcomes of 2 t(1;22)(p13;q13) AMKL patients with hepatic fibrosis. One patient died from liver failure despite the control of leukemia. The other patient was successfully treated with reduced-intensity chemotherapy and antifibrosis therapy with tretinoin and α-tocopheryl acetate, the hepatic fibrosis resolved and leukemia was in remission for 3 years.. Reduced-intensity chemotherapy plus antifibrosis therapy with tretinoin and α-tocopheryl acetate could be a treatment option for these patients with t(1;22)(p13;q13) AMKL and hepatic fibrosis.

Topics: alpha-Tocopherol; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Child, Preschool; Chromosomes, Human, Pair 1; Chromosomes, Human, Pair 22; Drug Therapy, Combination; Female; Humans; Infant, Newborn; Keratolytic Agents; Leukemia, Megakaryoblastic, Acute; Liver Cirrhosis; Prognosis; Translocation, Genetic; Tretinoin

Differentiation therapy has emerged as a powerful way to target specific hematologic malignancies. One of the best examples is the use of all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL), which has significantly improved the outcome for patients with this specific form of acute myeloid leukemia (AML). In considering how differentiation therapy could be used in other forms of AML, we predicted that compounds that induce terminal differentiation of megakaryocytes would be effective therapies for the megakaryocytic form of AML, named acute megakaryocytic leukemia (AMKL). We also speculated that such agents would reduce the burden of abnormal hematopoietic cells in primary myelofibrosis and alter the differentiation of megakaryocytes in myelodysplastic syndromes. Using a high-throughput chemical screening approach, we identified small molecules that promoted many features of terminal megakaryocyte differentiation, including the induction of polyploidization, the process by which cells accumulate DNA to 32N or greater. As the induction of polyploidization is an irreversible process, cells that enter this form of the cell cycle do not divide again. Thus, this would be an effective way to reduce the tumor burden. Clinical studies with polyploidy inducers, such as aurora kinase A inhibitors, are under way for a wide variety of malignancies, whereas trials specifically for AMKL and PMF are in development. This novel form of differentiation therapy may be clinically available in the not-too-distant future. Clin Cancer Res; 19(22); 6084-8. ©2013 AACR.

Topics: Antineoplastic Agents; Aurora Kinase A; Azepines; Cell Differentiation; Cell Line, Tumor; Humans; Leukemia, Megakaryoblastic, Acute; Leukemia, Promyelocytic, Acute; Megakaryocytes; Mitosis; Polyploidy; Primary Myelofibrosis; Protein Kinase Inhibitors; Pyrimidines; Tretinoin

We recently established a human granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent cell line (HML) from colony-constituent cells grown by peripheral blood cells of a patient with acute megakaryoblastic leukaemia. The HML cells possessed megakaryocytic features, as determined by cytochemical, electron microscopic and flow cytometric analysis. In the present study we examined the effects of retinoic acid (RA) on the development of HML cells. All-trans-RA, 13-cis-RA and 9-cis-RA at 10(-8) mol/l to 10(-5) mol/l inhibited the GM-CSF-dependent cell growth. Some of the RA-treated cells contained prominent azurophilic granules and were positive for peroxidase. They also reacted with Biebrich scarlet, Luxol fast blue and a monoclonal antibody against eosinophil peroxidase. In addition, exposure to RA increased the frequency and the intensity of major basic protein-positive cells. However, eosinophil-derived neurotoxin and eosinophil cationic protein were not detected or were only detected at a low level in the lysates of the HML cells treated with RA. Although IL-5 alone could not stimulate cell growth, the addition of IL-5 to the cultures containing stem cell factor + all-trans-RA was required for the expression of the eosinophilic phenotype. These results suggest that the HML cell line is a megakaryoblastic cell line with the potential to differentiate into the eosinophilic lineage. HML cells may be a useful model for elucidating the eosinophilic differentiation programme.

Topics: Cell Differentiation; Eosinophils; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Infant; Leukemia, Megakaryoblastic, Acute; Male; Megakaryocytes; Tretinoin; Tumor Cells, Cultured

Acute megakaryoblastic leukemia is uncommon and comprises about 5% of acute nonlymphoid leukemias in the French-American-British classification. Cell lines from such leukemias are relatively rare with only about 8 reported in the literature. We established a cell line from a case of acute megakaryoblastic leukemia arising in a 2-year-old child. Surface marker studies of the cells confirmed their megakaryoblastic nature, with 54% of the cells being CD61 positive and peroxidase and esterase negative. The cells had a doubling time of 72 h. Emperipolesis (a phenomenon in which a cell, usually a lymphocyte or neutrophil, enters another cell, moves about and leaves without undergoing phagocytosis) of one blast into another, larger one, was occasionally seen, and a review of the original bone marrow specimen also showed emperipolesis of neutrophils into the megakaryoblasts. The cells responded to interleukin 3 and were inhibited with all-trans-retinoic acid. The karyotype of the cells was the 46,XX,-16 with a marker chromosome. The marker chromosome is possibly chromosome 16 with a small segment of a chromosome translocated to the terminal portion of chromosome 16.

Topics: Antigens, CD; Antigens, CD34; Antigens, Differentiation, Myelomonocytic; Cell Culture Techniques; Cell Division; Cell Nucleus; Child, Preschool; Cytoplasm; Humans; Integrin beta3; Interleukin-3; Karyotyping; Leukemia, Megakaryoblastic, Acute; Platelet Glycoprotein GPIIb-IIIa Complex; Platelet Membrane Glycoproteins; Ploidies; Sialic Acid Binding Ig-like Lectin 3; Tretinoin; Tumor Cells, Cultured

Retinoic acid (RA) has profound suppressive effects on growth and survival of human growth factor-dependent cell line, M07e. Treatment of M07e cells by RA reduced expression of egr-1 gene, while the levels of c-myc gene expression remained similar. Suppression of egr-1 gene expression by RA was dosage-dependent and reached maximum at 4 h after RA addition. The decay of egr-1 mRNA was similar in M07e cells treated with or without RA. The transcriptional activity of the promoter region up to -600 or -480 bp upstream of the egr-1 gene was greatly reduced by RA treatment. These data suggest that biological effects of RA on hematopoietic cells may, in part, be mediated by transcriptional suppression of egr-1 gene through its promoter region within -480 bp.

Topics: DNA-Binding Proteins; Early Growth Response Protein 1; Gene Expression Regulation, Leukemic; Genes, Immediate-Early; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Immediate-Early Proteins; Leukemia, Megakaryoblastic, Acute; Megakaryocytes; Neoplasm Proteins; Promoter Regions, Genetic; Proto-Oncogene Proteins c-myc; Recombinant Proteins; RNA, Messenger; RNA, Neoplasm; Stem Cell Factor; Transcription Factors; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured

A panel of 164 continuous human leukemia-lymphoma cell lines was analyzed for expression of c-kit using Northern blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). The c-kit transcripts were detectable in cell lines assigned to the myeloid (in 7 of 29 by Northern blotting and in 4 of 8 by RT-PCR), monocytic (in 1 of 24 by Northern blotting and in 3 of 6 by RT-PCR), erythroid (in 6 of 8 by Northern blotting and in 5 of 5 by RT-PCR), and megakaryoblastic (in 10 of 10 by Northern blotting) lineages, c-kit expression was not seen by Northern blotting or RT-PCR analysis in any of the 93 lymphoid leukemia, myeloma, or lymphoma cell lines. Treatment of four megakaryoblastic cell lines with protein kinase C activators (phorbol ester 12-O-tetradecanoylphorbol 13-acetate and Bryostatin 1) led to terminal differentiation as assessed by morphologic alterations, changes in the surface marker profile, and growth arrest. These effects were associated with enhanced c-kit mRNA expression. Exposure to all-trans retinoic acid down-regulated c-kit mRNA levels, while simultaneously causing morphologic alterations in all four cell lines. Stimulation with growth factors (interleukin-3, granulocyte macrophage-colony stimulating factor, and insulin-like growth factors I and II), used to assess any role of c-kit in proliferative processes, did not lead to significant upregulation or downregulation of c-kit expression. The finding of constitutive and high expression of c-kit mRNA in all megakaryoblastic leukemia cell lines and its modulation by various reagents might further contribute to the understanding of megakaryopoietic proliferation, differentiation, and leukemogenesis.

Topics: Apoptosis; Base Sequence; Cytokines; DNA; Gene Expression; Humans; Immunophenotyping; Leukemia, Megakaryoblastic, Acute; Molecular Sequence Data; Polymerase Chain Reaction; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-kit; Proto-Oncogenes; Receptor Protein-Tyrosine Kinases; Receptors, Colony-Stimulating Factor; Tretinoin; Tumor Cells, Cultured