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Toxicology in Vitro : An International... Apr 2016In vertebrates, the retinol (vitamin A) signaling pathway (RSP) controls the biosynthesis and catabolism of all-trans retinoic acid (atRA), which regulates transcription...
In vertebrates, the retinol (vitamin A) signaling pathway (RSP) controls the biosynthesis and catabolism of all-trans retinoic acid (atRA), which regulates transcription of genes essential for embryonic development. Chemicals that interfere with the RSP to cause abnormal intracellular levels of atRA are potential developmental toxicants. To assess chemicals for the ability to interfere with retinol signaling, we have developed a cell-based RARE (Retinoic Acid Response Element) reporter gene assay to identify RSP disruptors. To validate this assay in a quantitative high-throughput screening (qHTS) platform, we screened the Library of Pharmacologically Active Compounds (LOPAC) in both agonist and antagonist modes. The screens detected known RSP agonists, demonstrating assay reliability, and also identified novel RSP agonists including kenpaullone, niclosamide, PD98059 and SU4312, and RSP antagonists including Bay 11-7085, LY294002, 3,4-Methylenedioxy-β-nitrostyrene, and topoisomerase inhibitors (camptothecin, topotecan, amsacrine hydrochloride, and idarubicin). When evaluated in the P19 pluripotent cell, these compounds were found to affect the expression of the Hoxa1 gene that is essential for embryo body patterning. These results show that the RARE assay is an effective qHTS approach for screening large compound libraries to identify chemicals that have the potential to adversely affect embryonic development through interference with retinol signaling.
Topics: Animals; Cell Line; Genes, Reporter; High-Throughput Screening Assays; Luciferases; Mice; Response Elements; Signal Transduction; Vitamin A
PubMed: 26820057
DOI: 10.1016/j.tiv.2016.01.011 -
Journal of Clinical Oncology : Official... Mar 2021Reduced-intensity conditioning (RIC) regimens have extended the curative potential of allogeneic stem-cell transplantation to older adults with high-risk acute myeloid... (Comparative Study)
Comparative Study Randomized Controlled Trial
PURPOSE
Reduced-intensity conditioning (RIC) regimens have extended the curative potential of allogeneic stem-cell transplantation to older adults with high-risk acute myeloid leukemia (AML) and myelodysplasia (MDS) but are associated with a high risk of disease relapse. Strategies to reduce recurrence are urgently required. Registry data have demonstrated improved outcomes using a sequential transplant regimen, fludarabine/amsacrine/cytarabine-busulphan (FLAMSA-Bu), but the impact of this intensified conditioning regimen has not been studied in randomized trials.
PATIENTS AND METHODS
Two hundred forty-four patients (median age, 59 years) with high-risk AML (n = 164) or MDS (n = 80) were randomly assigned 1:1 to a fludarabine-based RIC regimen or FLAMSA-Bu. Pretransplant measurable residual disease (MRD) was monitored by flow cytometry (MFC-MRD) and correlated with outcome.
RESULTS
There was no difference in 2-year overall survival (hazard ratio 1.05 [85% CI, 0.80 to 1.38] = .81) or cumulative incidence of relapse (CIR) (hazard ratio 0.94 [95%CI, 0.60 to 1.46] = .81) between the control and FLAMSA-Bu arms. Detectable pretransplant MFC-MRD was associated with an increased CIR (2-year CIR 41.0% 20.0%, = .01) in the overall trial cohort with a comparable prognostic impact when measured by an unsupervised analysis approach. There was no evidence of interaction between MRD status and conditioning regimen intensity for relapse or survival. Acquisition of full donor T-cell chimerism at 3 months abrogated the adverse impact of pretransplant MRD on CIR and overall survival.
CONCLUSION
The intensified RIC conditioning regimen, FLAMSA-Bu, did not improve outcomes in adults transplanted for high-risk AML or MDS regardless of pretransplant MRD status. Our data instead support the exploration of interventions with the ability to accelerate acquisition of full donor T-cell chimerism as a tractable strategy to improve outcomes in patients allografted for AML.
Topics: Adult; Aged; Amsacrine; Busulfan; Cytarabine; Female; Graft vs Host Disease; Humans; Immunosuppressive Agents; Leukemia, Myeloid, Acute; Male; Middle Aged; Myeloablative Agonists; Myelodysplastic Syndromes; Progression-Free Survival; Recurrence; Stem Cell Transplantation; Time Factors; Transplantation Conditioning; Transplantation, Homologous; United Kingdom; Vidarabine; Young Adult
PubMed: 33373276
DOI: 10.1200/JCO.20.02308 -
Transplantation and Cellular Therapy May 2022Patients with relapsed/refractory acute myeloid leukemia (AML) have a dismal prognosis. Allogeneic stem cell transplantation (allo-SCT) provides a curative approach;...
Patients with relapsed/refractory acute myeloid leukemia (AML) have a dismal prognosis. Allogeneic stem cell transplantation (allo-SCT) provides a curative approach; however, the overall survival (OS) remains low (20% to 40%). In this setting, although some effective approaches have been evaluated in recent years, the management of such patients still remains challenging. In this study we evaluated the predictive role of post-transplant day 100 minimal residual disease (MRD) detection for post-transplantation outcomes for patients with refractory AML. Fifty-six adult patients with refractory AML (median age 58, range 20-76; male, 61%) who underwent allo-SCT were included in this retrospective monocentric study. Twenty-nine patients (52%) received fludarabine, amsacrine, and cytarabine (FLAMSA)-based conditioning. MRD was assessed using multicolored flow cytometry (MFC) according to European Leukemia Net guidelines ("different from normal" and leukemia-associated phenotype). The sensitivity of the method was 10 to 10. The median marrow blast count at allo-SCT was 25% (range 6% to 91%). At day 100 after transplantation, 40 patients (71%) experienced MFC-MRD negativity, and 16 patients (29%) were MRD positive. All included patients survived at least 100 days after transplantation without relapse. Univariate and multivariate analysis based on Kaplan-Meier and Cox proportional hazards method were performed. The median follow-up was 16 months (range 3 to 66). The post-transplantation day 100 MRD-negative patients instead received 2 allografts (27% versus 6%, P = .08). In multivariate analysis, day 100 MRD status (negative versus positive) (OS: 0.23 [0.1 to 0.54], P =0.001; relapses: 0.20 [0.1 to 0.49], P = .0005) and FLAMSA versus other regimens (0.34 [0.1 to 0.83], P = .018; relapses: 0.43 [0.17 to 1.1], P = .07) independently impacted post-transplantation survival. We suggest that post-transplantation day 100 MFC-MRD detection plays predictive role in refractory AML patients and may help to define possible candidates for early post-transplantation interventions aiming to decrease the relapse risk and improve survival.
Topics: Flow Cytometry; Humans; Leukemia, Myeloid, Acute; Male; Neoplasm, Residual; Recurrence; Retrospective Studies
PubMed: 35066212
DOI: 10.1016/j.jtct.2022.01.014 -
Proceedings of the National Academy of... Mar 1993In an effort to further extend the number of targets for development of antiretroviral agents, we have used an in vitro integrase assay to investigate a variety of... (Comparative Study)
Comparative Study
In an effort to further extend the number of targets for development of antiretroviral agents, we have used an in vitro integrase assay to investigate a variety of chemicals, including topoisomerase inhibitors, antimalarial agents, DNA binders, naphthoquinones, the flavone quercetin, and caffeic acid phenethyl ester as potential human immunodeficiency virus type 1 integrase inhibitors. Our results show that although several topoisomerase inhibitors--including doxorubicin, mitoxantrone, ellipticines, and quercetin--are potent integrase inhibitors, other topoisomerase inhibitors--such as amsacrine, etoposide, teniposide, and camptothecin--are inactive. Other intercalators, such as chloroquine and the bifunctional intercalator ditercalinium, are also active. However, DNA binding does not correlate closely with integrase inhibition. The intercalator 9-aminoacridine and the polyamine DNA minor-groove binders spermine, spermidine, and distamycin have no effect, whereas the non-DNA binders primaquine, 5,8-dihydroxy-1,4-naphthoquinone, and caffeic acid phenethyl ester inhibit the integrase. Caffeic acid phenethyl ester was the only compound that inhibited the integration step to a substantially greater degree than the initial cleavage step of the enzyme. A model of 5,8-dihydroxy-1,4-naphthoquinone interaction with the zinc finger region of the retroviral integrase protein is proposed.
Topics: Antibiotics, Antineoplastic; Antiviral Agents; Base Sequence; DNA Nucleotidyltransferases; Enzyme Inhibitors; HIV-1; Integrases; Kinetics; Molecular Sequence Data; Naphthoquinones; Oligodeoxyribonucleotides; Recombinant Proteins; Structure-Activity Relationship; Substrate Specificity
PubMed: 8460151
DOI: 10.1073/pnas.90.6.2399 -
Journal of Clinical Oncology : Official... Mar 2021The optimum number of treatment courses for younger patients with acute myeloid leukemia (AML) is uncertain. The United Kingdom National Cancer Research Institute AML17... (Comparative Study)
Comparative Study Randomized Controlled Trial
PURPOSE
The optimum number of treatment courses for younger patients with acute myeloid leukemia (AML) is uncertain. The United Kingdom National Cancer Research Institute AML17 trial randomly assigned patients who were not high risk to a total of three versus four courses.
PATIENTS AND METHODS
Patients received two induction courses based on daunorubicin and cytarabine (Ara-C), usually with gemtuzumab ozogamicin. Following remission, 1,017 patients were randomly assigned to a third course, MACE (amsacrine, Ara-C, and etoposide), plus a fourth course of MidAc (mitoxantrone and Ara-C) and following an amendment to one or two courses of high-dose Ara-C. Primary end points were cumulative incidence of relapse (CIR), relapse-free survival (RFS), and overall survival (OS). Outcomes were correlated with patient characteristics, mutations, cytogenetics, induction treatments, and measurable residual disease (MRD) postinduction.
RESULTS
In logrank analyses, CIR and RFS at 5 years were improved in recipients of four courses (50% 58%: hazard ratio [HR] 0.81 [0.69-0.97], = .02 and 43% 36%: HR 0.83 [0.71-0.98], = .03, respectively). While OS was not significantly better (63% 57%: HR 0.84 [0.69-1.03], = .09), the noninferiority of three courses to four courses was not established. The impact on relapse was only significant when the fourth course was Ara-C. In exploratory analyses, although MRD impacted survival, a fourth course had no effect in either MRD-positive or MRD-negative patients. A fourth course was beneficial in patients who lacked a mutation of or , had < 3 mutations in other genes, or had a presenting WBC of < 10 × 10 L.
CONCLUSION
Although a fourth course of high-dose Ara-C reduced CIR and improved RFS, it did not result in a significant OS benefit. Subsets including those with favorable cytogenetics, those lacking a mutation of , or those with < 3 other mutations may derive survival benefit.
Topics: Adolescent; Adult; Age Factors; Aged; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Daunorubicin; Etoposide; Female; Follow-Up Studies; Gemtuzumab; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Nucleophosmin; Prognosis; Survival Rate; Young Adult
PubMed: 33356418
DOI: 10.1200/JCO.20.01170 -
Cell Death & Disease Oct 2017Autophagy promotes cancer cell survival and drug resistance by degrading harmful cellular components and maintaining cellular energy levels. Disruption of autophagy may...
Autophagy promotes cancer cell survival and drug resistance by degrading harmful cellular components and maintaining cellular energy levels. Disruption of autophagy may be a promising approach to sensitize cancer cells to anticancer drugs. The combination of autophagic inhibitors, such as chloroquine (CQ) and lucanthone with conventional cancer therapeutics has been investigated in clinical trials, but adverse drug-drug interactions are a high possibility. Here we designed and synthesized a novel, small-molecule library based on an acridine skeleton and the CQ structure with various modifications and substitutions and screened the compounds for effective autophagy inhibition. We found that 9-chloro-2-(3-(dimethylamino)propyl)pyrrolo[2,3,4-kl]acridin-1(2H)-one (LS-1-10) was the most effective from our library at inhibiting autophagic-mediated degradation and could decrease the viability of multiple colon cancer cells. In addition, LS-1-10 induced DNA damage and caspase 8-mediated apoptosis. Overall, this small molecule was more efficient at reducing the viability of cancer cells than other conventional chemotherapeutic agents, such as CQ and amsacrine. The anticancer and autophagy-inhibiting activities of LS-1-10 were confirmed in vivo in a xenograft mouse model. Collectively, this study has identified a new and efficient single compound with both autophagy-inhibiting and anticancer activity, which may provide a novel approach for cancer therapy.
Topics: Acridines; Animals; Apoptosis; Autophagy; Cell Line, Tumor; Cell Survival; Chloroquine; Colonic Neoplasms; Drug Resistance, Neoplasm; Humans; Mice; Proteolysis; Xenograft Model Antitumor Assays
PubMed: 28981103
DOI: 10.1038/cddis.2017.498 -
British Journal of Cancer Jan 1991Cell lines resistant to adriamycin and amsacrine were derived from cloned sublines of the human T cell line Jurkat. Most of the lines resemble atypical MDR cells (Danks... (Comparative Study)
Comparative Study
Cell lines resistant to adriamycin and amsacrine were derived from cloned sublines of the human T cell line Jurkat. Most of the lines resemble atypical MDR cells (Danks et al., 1987; Beck et al., 1987). Thus, resistant Jurkat sublines were cross resistant to several topoisomerase II inhibiting drugs but had low or no resistance to other classes of drugs, resistance was not reversed by verapamil, Pgp was not overexpressed, and drug accumulation was unaltered in resistant compared to parental (control) sublines. Other findings were that anthracycline metabolism differed between resistant and parental sublines, and that resistant sublines displayed altered expression of small polypeptides (less than 20K MW) and an 85K MW protein. Drug resistant cells showed resistance to the production of drug induced cytogenetic aberrations, DNA breaks, and protein-DNA complexes. Resistance was not mediated by altered binding of drugs to DNA or by increased repair of DNA damage. Indirect evidence suggests that the resistant cells had an altered drug-DNA-topoisomerase II association. The study highlights the complex relationships between DNA breaks, cytogenetic aberrations, protein-DNA complexes and drug cytotoxicity, and shows that the relationships differ for adriamycin and amsacrine, suggesting some differences in the modes of action and/or resistance for the drugs and cell lines.
Topics: Amsacrine; Clone Cells; Cytotoxicity, Immunologic; DNA Damage; DNA, Neoplasm; DNA-Binding Proteins; Doxorubicin; Drug Resistance; Electrophoresis, Polyacrylamide Gel; Fluorescence; Gene Amplification; Humans; Karyotyping; Leukemia, T-Cell; Neoplasm Proteins; Sodium Dodecyl Sulfate; Tumor Cells, Cultured
PubMed: 1989661
DOI: 10.1038/bjc.1991.7 -
Blood Mar 2017Clofarabine has demonstrated antileukemic activity in acute myeloid leukemia (AML) but has yet to be critically evaluated in younger adults in the frontline with... (Randomized Controlled Trial)
Randomized Controlled Trial
Clofarabine has demonstrated antileukemic activity in acute myeloid leukemia (AML) but has yet to be critically evaluated in younger adults in the frontline with standard chemotherapy. We compared 2 induction regimens in newly diagnosed patients ages 18 to 65 with acute myeloid leukemia (AML)/high-risk myelodysplastic syndromes, that is, idarubicine-cytarabine (cycle I) and amsacrine-cytarabine (cycle II) without or with clofarabine (10 mg/m on days 1-5 of each of both cycles). Consolidation involved chemotherapy with or without hematopoietic stem cell transplantation. Event-free survival (EFS, primary endpoint) and other clinical endpoints and toxicities were assessed. We randomized 402 and 393 evaluable patients to the control or clofarabine induction treatment arms. Complete remission rates (89%) did not differ but were attained faster with clofarabine (66% vs 75% after cycle I). Clofarabine added grades 3 to 4 toxicities and delayed hematological recovery. At a median follow-up of 36 months, the study reveals no differences in overall survival and EFS between the control (EFS, 35% ± 3 [standard error] at 4 years) and clofarabine treatments (38% ± 3) but a markedly reduced relapse rate (44% ± 3 vs 35% ± 3) in favor of clofarabine and an increased death probability in remission (15% ± 2 vs 22% ± 3). In the subgroup analyses, clofarabine improved overall survival and EFS for European Leukemia Net (ELN) 2010 intermediate I prognostic risk AML (EFS, 26% ± 4 vs 40% ± 5 at 4 years; Cox = .002) and for the intermediate risk genotype wild-type/ without internal-tandem duplications (EFS, 18% ± 5 vs 40% ± 7; Cox < .001). Clofarabine improves survival in subsets of intermediate-risk AML only. HOVON-102 study is registered at Netherlands Trial Registry #NTR2187.
Topics: Adenine Nucleotides; Adolescent; Adult; Aged; Antimetabolites, Antineoplastic; Arabinonucleosides; Clofarabine; Consolidation Chemotherapy; Humans; Induction Chemotherapy; Leukemia, Myeloid, Acute; Middle Aged; Nucleophosmin; Remission Induction; Risk; Survival Rate; Young Adult
PubMed: 28049642
DOI: 10.1182/blood-2016-10-740613 -
Transplantation and Cellular Therapy Jan 2023Allogeneic hematopoietic stem cell transplantation (allo-HSCT) after conditioning with a sequential association of fludarabine, amsacrine, and cytosine arabinoside...
Impact on Outcome of Minimal Residual Disease after Hematopoietic Stem Cell Transplantation with Fludarabine, Amsacrine, and Cytosine Arabinoside-Busulfan Conditioning: A Retrospective Monocentric Study.
Allogeneic hematopoietic stem cell transplantation (allo-HSCT) after conditioning with a sequential association of fludarabine, amsacrine, and cytosine arabinoside (FLAMSA) followed by a reduced-intensity conditioning regimen has emerged for patients with high-risk acute myeloid leukemia (AML), especially in refractory or relapsing patients. Here we aimed to address retrospectively the impact of pretransplantation minimal residual disease (MRD) by flow cytometry on the outcomes of high-risk AML patients who underwent allo-HSCT after sequential FLAMSA-busulfan (FLAMSA-Bu)-based conditioning regimens. We included 165 high-risk AML patients who underwent transplantation after FLAMSA-BU in this retrospective single-center "real life" study. All patients received in vivo T cell depletion with antithymocyte globulin (5 mg/kg). MRD detection was based on a leukemia-associated immunophenotype using the European LeukemiaNet recommendations, with a threshold of .1%. Univariate and multivariate analyses were performed using R version 4.1.1 (R Foundation for Statistical Computing, Vienna, Austria). With a median follow-up of 4.0 years post-transplantation, the median overall survival (OS) was 54.9 months. Overall, 41 patients (24.8%) relapsed post-transplantation, with a resulting cumulative incidence of relapse (CIR) of 26.7% at 2 years and 34.0% at 5 years. Detectable MRD preceding allo-HSCT and refractory status were associated with worse median OS and CIR rates compared with patients without detectable MRD; however, OS was not significantly different between pre-HSCT MRD-positive and refractory patients (median, .7 year versus 2.0 years; P = .3). Conversely, pre-HSCT MRD negativity was associated with a reduced 2-year CIR. Neither European LeukemiaNet risk stratification nor age had a significant influence on OS. In the multivariate analysis, only pre-HSCT MRD positivity and lower conditioning regimen intensity were significantly associated with a poorer OS. The cumulative incidence of extensive chronic graft-versus-host disease at 2 years was 26.15%. The estimated nonrelapse mortality (NRM) of the entire cohort at 2 years was 23.1%, with age and unrelated donor identified as risk factors for higher NRM. Our data ahow that FLAMSA-Bu conditioning did not reverse the pejorative effect of detectable pre-HSCT MRD, suggesting that such patients should be offered alternative strategies before HSCT to reach deeper remission.
Topics: Humans; Busulfan; Amsacrine; Retrospective Studies; Cytarabine; Neoplasm, Residual; Leukemia, Myeloid, Acute; Hematopoietic Stem Cell Transplantation; Recurrence
PubMed: 36108977
DOI: 10.1016/j.jtct.2022.09.003 -
Bulletin Du Cancer Oct 1997Amsacrine is an intercalating planar polycyclic aromatic molecule that displays antitumor activity. The cytotoxicity of this compound is related to its interaction with... (Review)
Review
Amsacrine is an intercalating planar polycyclic aromatic molecule that displays antitumor activity. The cytotoxicity of this compound is related to its interaction with topoisomerase II. The substituent at position 1' on the aniline is thought to be essential to the formation of the topoisomerase II-DNA cleavable complex and hence the cytotoxicity of the drug. The influence of three substituents at position 1' on the modulation of the activity of topoisomerase II was investigated. The following observations emerge from our structure-activity relationship study: i) the effects of the drugs on topoisomerase II-mediated DNA cleavage in vitro are correlated with the results of the cytotoxicity assays performed with cells sensitive (DC-3F) and resistant to topoisomerase II inhibitors (DC-3F/9-OH-E); ii) depending on the nature of the 1' substituent of the drugs, the restoration of a normal topoisomerase II alpha catalytic activity in resistant DC-3F/9-OH-E cells transfected with a plasmid carrying a wild type topoisomerase II alpha cDNA (hTOP2) either does not modify the susceptibility of the cells to the drug or partially reverse the resistance phenotype. The molecular and cellular studies reveal that topoisomerase II alpha is implicated in the cytotoxicity of amsacrine and confirm that the substituent at position 1' on the anilino ring of amsacrine governs the interaction with topoisomerase II.
Topics: Amsacrine; Animals; Antineoplastic Agents; Cattle; Cell Survival; DNA Topoisomerases, Type II; Electrophoresis, Agar Gel; Enzyme Inhibitors; Humans; In Vitro Techniques; Structure-Activity Relationship; Topoisomerase II Inhibitors
PubMed: 9435795
DOI: No ID Found