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1.
Photochem Photobiol Sci ; 23(1): 31-53, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38070056

RESUMEN

There is a need to shift the absorbance of biomolecules to the optical transparency window of tissue for applications in optogenetics and photo-pharmacology. There are a few strategies to achieve the so-called red shift of the absorption maxima. Herein, a series of 11 merocyanine dyes were synthesized and employed as chromophores in place of retinal in bacteriorhodopsin (bR) to achieve a bathochromic shift of the absorption maxima relative to bR's [Formula: see text] of 568 nm. Assembly with the apoprotein bacterioopsin (bO) led to stable, covalently bound chromoproteins with strongly bathochromic absorbance bands, except for three compounds. Maximal red shifts were observed for molecules 9, 2, and 8 in bR where the [Formula: see text] was 766, 755, and 736 nm, respectively. While these three merocyanines have different end groups, they share a similar structural feature, namely, a methyl group which is located at the retinal equivalent position 13 of the polyene chain. The absorption and fluorescence data are also presented for the retinal derivatives in their aldehyde, Schiff base (SB), and protonated SB (PSB) forms in solution. According to their hemicyanine character, the PSBs and their analogue bRs exhibited fluorescence quantum yields (Φf) several orders of magnitude greater than native bR (Φf 0.02 to 0.18 versus 1.5 × 10-5 in bR) while also exhibiting much smaller Stokes shifts than bR (400 to 1000 cm-1 versus 4030 cm-1 in bR). The experimental results are complemented by quantum chemical calculations where excellent agreement between the experimental [Formula: see text] and the calculated [Formula: see text] was achieved with the second-order algebraic-diagrammatic construction [ADC(2)] method. In addition, quantum mechanics/molecular mechanics (QM/MM) calculations were employed to shed light on the origin of the bathochromic shift of merocyanine 2 in bR compared with native bR.

2.
Int J Mol Sci ; 25(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38928138

RESUMEN

Based on the lack of differences in progression-free and overall survival after a median follow-up of 93 months in our HOVON-65/GMMG-HD4 trial (German part; n = 395) randomizing VAD induction (vincristin/adriamycin/dexamthasone)/tandem-transplantation/thalidomide-maintenance vs. PAD induction (bortezomib/adriamycin/dexamethasone)/tandem transplantation/bortezomib maintenance, we discern how chromosomal aberrations determine long-term prognosis by different patterns of association with proliferation and treatment-dependent response, whether responses achieved by different regimens are equal regarding prognosis, and whether subpopulations of patients could be defined as treatable without upfront "novel agents" in cases of limited resources, e.g., in low- or middle-income countries. Serum parameters and risk factors were assessed in 395 patients. CD138-purified plasma cells were subjected to fluorescence in situ hybridization (n = 354) and gene expression profiling (n = 204). We found chromosomal aberrations to be associated in four patterns with survival, proliferation, and response: deletion (del) del17p13, del8p21, del13q14, (gain) 1q21+, and translocation t(4;14) (all adverse) associate with higher proliferation. Of these, del17p is associated with an adverse response (pattern 1), and 1q21+, t(4;14), and del13q14 with a treatment-dependent better response (pattern 2). Hyperdiploidy associates with lower proliferation without impacting response or survival (pattern 3). Translocation t(11;14) has no association with survival but a treatment-dependent adverse response (pattern 4). Significantly fewer patients reach a near-complete response or better with "conventional" (VAD) vs. bortezomib-based treatment after induction or high-dose melphalan. These patients, however, show significantly better median progression-free and overall survival. Molecularly, patients responding to the two regimens differ in gene expression, indicating distinct biological properties of the responding myeloma cells. Patients with normal renal function (89.4%), low cytogenetic risk (72.5%), or low proliferation rate (37.9%) neither benefit in progression-free nor overall survival from bortezomib-based upfront treatment. We conclude that response level, the treatment by which it is achieved, and molecular background determine long-term prognosis. Chromosomal aberrations are associated in four patterns with proliferation and treatment-dependent responses. Associations with faster and deeper responses can be deceptive in the case of prognostically adverse aberrations 1q21+ and t(4;14). Far from advocating a return to "outdated" treatments, if resources do not permit state-of-the-art-treatment, normal renal function and/or molecular profiling identifies patient subpopulations doing well without upfront "novel agents".


Asunto(s)
Aberraciones Cromosómicas , Mieloma Múltiple , Humanos , Mieloma Múltiple/genética , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Femenino , Masculino , Persona de Mediana Edad , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Proliferación Celular/efectos de los fármacos , Pronóstico , Adulto , Países en Desarrollo , Dexametasona/uso terapéutico , Dexametasona/farmacología , Bortezomib/uso terapéutico , Bortezomib/farmacología , Talidomida/uso terapéutico
3.
Sensors (Basel) ; 23(19)2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37837060

RESUMEN

We demonstrate the successful implementation of an artificial neural network (ANN) to eliminate detrimental spectral shifts imposed in the measurement of laser absorption spectrometers (LASs). Since LASs rely on the analysis of the spectral characteristics of biological and chemical molecules, their accuracy and precision is especially prone to the presence of unwanted spectral shift in the measured molecular absorption spectrum over the reference spectrum. In this paper, an ANN was applied to a scanning grating-based mid-infrared trace gas sensing system, which suffers from temperature-induced spectral shifts. Using the HITRAN database, we generated synthetic gas absorbance spectra with random spectral shifts for training and validation. The ANN was trained with these synthetic spectra to identify the occurrence of spectral shifts. Our experimental verification unambiguously proves that such an ANN can be an excellent tool to accurately retrieve the gas concentration from imprecise or distorted spectra of gas absorption. Due to the global shift of the measured gas absorption spectrum, the accuracy of the retrieved gas concentration using a typical least-mean-squares fitting algorithm was considerably degraded by 40.3%. However, when the gas concentration of the same measurement dataset was predicted by the proposed multilayer perceptron network, the sensing accuracy significantly improved by reducing the error to less than ±1% while preserving the sensing sensitivity.

4.
Strahlenther Onkol ; 198(6): 547-557, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35318487

RESUMEN

PURPOSE: Total body irradiation (TBI) is a common part of the myelo- and immuno-ablative conditioning regimen prior to an allogeneic hematopoietic stem cell transplantation (allo-HSCT). Due to concerns regarding acute and long-term complications, there is currently a decline in otherwise successfully established TBI-based conditioning regimens. Here we present an analysis of patient and treatment data with focus on survival and long-term toxicity. METHODS: Patients with hematologic diseases who received TBI as part of their conditioning regimen prior to allo-HSCT at Frankfurt University Hospital between 1997 and 2015 were identified and retrospectively analyzed. RESULTS: In all, 285 patients with a median age of 45 years were identified. Median radiotherapy dose applied was 10.5 Gy. Overall survival at 1, 2, 5, and 10 years was 72.6, 64.6, 54.4, and 51.6%, respectively. Median follow-up of patients alive was 102 months. The cumulative incidence of secondary malignancies was 12.3% (n = 35), with hematologic malignancies and skin cancer predominating. A TBI dose ≥ 8 Gy resulted in significantly improved event-free (p = 0.030) and overall survival (p = 0.025), whereas a total dose ≤ 8 Gy and acute myeloid leukemia (AML) diagnosis were associated with significantly increased rates of secondary malignancies (p = 0.003, p = 0.048) in univariate analysis. No significant correlation was observed between impaired renal or pulmonary function and TBI dose. CONCLUSION: TBI remains an effective and well-established treatment, associated with distinct late-toxicity. However, in the present study we cannot confirm a dose-response relationship in intermediate dose ranges. Survival, occurrence of secondary malignancies, and late toxicities appear to be subject to substantial confounding in this context.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Neoplasias Primarias Secundarias , Enfermedad Injerto contra Huésped/epidemiología , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Leucemia Mieloide Aguda/complicaciones , Persona de Mediana Edad , Neoplasias Primarias Secundarias/etiología , Estudios Retrospectivos , Acondicionamiento Pretrasplante/efectos adversos , Acondicionamiento Pretrasplante/métodos , Irradiación Corporal Total/efectos adversos
5.
Ecol Appl ; 32(5): e2580, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35319129

RESUMEN

Recovering endangered species is a difficult and often controversial task that challenges status quo land uses. Southern Mountain caribou are a threatened ecotype of caribou that historically ranged in southwestern Canada and northwestern USA and epitomize the tension between resource extraction, biodiversity conservation, and Indigenous Peoples' treaty rights. Human-induced habitat alteration is considered the ultimate cause of caribou population declines, whereby an increased abundance of primary prey-such as moose and deer-elevates predator populations and creates unsustainable caribou mortality. Here we focus on the Klinse-Za and Quintette subpopulations, part of the endangered Central Group of Southern Mountain caribou in British Columbia. These subpopulations were trending toward immediate extirpation until a collaborative group initiated recovery by implementing two short-term recovery actions. We test the effectiveness of these recovery actions-maternity penning of adult females and their calves, and the reduction of a primary predator, wolves-in increasing vital rates and population growth. Klinse-Za received both recovery actions, whereas Quintette only received wolf reductions, providing an opportunity to test efficacy between recovery actions. Between 1995 and 2021, we followed 162 collared female caribou for 414 animal-years to estimate survival and used aerial counts to estimate population abundance and calf recruitment. We combined these data in an integrated population model to estimate female population growth, total population abundance, and recovery action effectiveness. Results suggest that the subpopulations were declining rapidly (λ = 0.90-0.93) before interventions and would have been functionally extirpated (<10 animals) within 10-15 years. Wolf reduction increased population growth rates by ~0.12 for each subpopulation. Wolf reduction halted the decline of Quintette caribou and allowed them to increase (λ = 1.05), but alone would have only stabilized the Klinse-Za (λ = 1.02). However, maternity penning in the Klinse-Za increased population growth by a further ~0.06, which when combined with wolf reductions, allowed populations to grow (λ = 1.08). Taken together, the recovery actions in these subpopulations increased adult female survival, calf recruitment, and overall population growth, more than doubling abundance. Our results suggest that maternity penning and wolf reductions can be effective at increasing caribou numbers in the short term, while long-term commitments to habitat protection and restoration are made.


Asunto(s)
Ciervos , Reno , Lobos , Animales , Colombia Británica , Ciervos/fisiología , Demografía , Ecosistema , Femenino , Conducta Predatoria/fisiología , Embarazo , Reno/fisiología , Lobos/fisiología
6.
Am J Hematol ; 96(10): 1186-1194, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34152630

RESUMEN

Allogeneic hematopoietic cell transplantation (allo-HCT) is increasingly used in older myelofibrosis (MF) patients, but its risk/benefit ratio compared to non-transplant approaches has not been evaluated in this population. We analyzed the outcomes of allo-HCT in 556 MF patients aged ≥65 years from the EBMT registry, and determined the excess mortality over the matched general population of MF patients ≥65 years managed with allo-HCT (n = 556) or conventional drug treatment (n = 176). The non-transplant cohort included patients with intermediate-2 or high risk DIPSS from the Spanish Myelofibrosis Registry. After a median follow-up of 3.4 years, the estimated 5-year survival rate, non-relapse mortality (NRM), and relapse incidence after transplantation was 40%, 37%, and 25%, respectively. Busulfan-based conditioning was associated with decreased mortality (HR: 0.7, 95% CI: 0.5-0.9) whereas the recipient CMV+/donor CMV- combination (HR: 1.7, 95% CI: 1.2-2.4) and the JAK2 mutated genotype (HR: 1.9, 95% CI: 1.1-3.5) predicted higher mortality. Busulfan-based conditioning correlated with improved survival due to less NRM, despite its higher relapse rate when compared with melphalan-based regimens. Excess mortality was higher in transplanted patients than in the non-HCT cohort in the first year of follow-up (ratio: 1.93, 95% CI: 1.13-2.80), whereas the opposite occurred between the fourth and eighth follow-up years (ratio: 0.31, 95% CI: 0.18-0.53). Comparing the excess mortality of the two treatments, male patients seemed to benefit more than females from allo-HCT, mainly due to their worse prognosis with non-transplant approaches. These findings could potentially enhance counseling and treatment decision-making in elderly transplant-eligible MF patients.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Mielofibrosis Primaria/terapia , Factores de Edad , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Mielofibrosis Primaria/epidemiología , Sistema de Registros , España/epidemiología , Análisis de Supervivencia , Trasplante Homólogo
7.
Cancer ; 124(2): 286-296, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-28960264

RESUMEN

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative treatment option for patients with acute myeloid leukemia (AML). During transplantation, patients undergo a period of severe neutropenia, which puts them at high risk for infectious complications. However, the impact of patient colonization with multidrug-resistant organisms (MDRO) on overall survival remains unclear. METHODS: In this retrospective, single-center study, the authors analyzed data from 264 patients with AML who underwent a first allo-HSCT between January 2006 and March 2016 at their institution. Primary endpoints were overall survival and nonrelapse-related mortality. RESULTS: One hundred forty-two of 264 patients (53.8%) were colonized by at least 1 MDRO, mainly with vancomycin-resistant Enterococcus faecalis/faecium (n = 122). The characteristics of colonized patients did not differ from those of MDRO-negative patients with respect to median age (53.5 vs 53 years), cytogenetic risk according to European LeukemiaNet criteria, remission status before allo-HSCT (first or second complete remission: 55.7% vs 60.7%, respectively; active disease: 44.4% vs 39.3%, respectively), donor type, or hematopoietic cell transplantation-comorbidity index (HCT-CI). Compared with noncolonized patients, MDRO-positive patients had an inferior probability of survival at 5 years (43.3% vs 65.5%; P = .002), primarily because of a higher cumulative incidence of nonrelapse-related mortality (33.9% vs 9.4%; P < .001). Death caused by infections occurred in 15.5% of colonized patients versus 4.9% of noncolonized patients. There was no difference in the cumulative incidence of relapse in MDRO-positive versus MDRO-negative patients (33.8% vs 42.1%, respectively; P = .798). CONCLUSIONS: The current data emphasize the importance of regular MDRO screenings and prompt further investigations into the impact of colonization with MDRO on the immune system after allo-HSCT. Cancer 2018;124:286-96. © 2017 American Cancer Society.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda/terapia , Adulto , Anciano , Farmacorresistencia Bacteriana Múltiple , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/aislamiento & purificación , Femenino , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia Mieloide Aguda/microbiología , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplante Homólogo , Resistencia a la Vancomicina
8.
Eur J Haematol ; 2018 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-30048011

RESUMEN

BACKGROUND: In hematology and oncology, in particular in the setting of allogeneic hematopoietic stem cell transplantation (allo-HSCT), vancomycin-resistant Enterococcus spp. (VRE) colonization rates are high due to previous hospital stays and preceding antibiotic treatment and colonized patients have a lower overall survival (OS). OBJECTIVE: We reanalyzed our previously published cohort, to unravel which colonization timepoints before and during allo-HSCT might be predictive for the subsequent outcome. PATIENTS AND METHODS: We report about 268 patients with acute myeloid leukemia receiving an allo-HSCT between 2006 and 2016. RESULTS: We identified 129 never-colonized patients, 15 previously colonized patients (positive only before admission for allo-HSCT), 41 persistently colonized patients (positive before and at admission for allo-HSCT), and 83 newly colonized patients (positive only during allo-HSCT). Persistently and newly colonized patients had a worse 60 months OS due to increased incidence of non-relapse-related mortality (NRM) than never-colonized patients (OS: never-colonized: 61.0% vs persistently colonized: 43.5%; P = 0.023 vs newly colonized: 45.6%; P = 0.046). In contrast, OS and NRM of never-colonized and previously colonized patients as well as between persistently and newly colonized patients were similar. CONCLUSION: Patients can lose their VRE colonization status and acquisition of VRE during inpatient stay for allo-HSCT decreases survival to a similar extend as persistent colonization.

9.
Molecules ; 23(11)2018 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-30469331

RESUMEN

Hop-derived compounds have been subjected to numerous biomedical studies investigating their impact on a wide range of pathologies. Isomerised bitter acids (isoadhumulone, isocohumulone and isohumulone) from hops, used in the brewing process of beer, are known to inhibit members of the aldo-keto-reductase superfamily. Aldo-keto-reductase 1B10 (AKR1B10) is upregulated in various types of cancer and has been reported to promote carcinogenesis. Inhibition of AKR1B10 appears to be an attractive means to specifically treat RAS-dependent malignancies. However, the closely related reductases AKR1A1 and AKR1B1, which fulfil important roles in the detoxification of endogenous and xenobiotic carbonyl compounds oftentimes crossreact with inhibitors designed to target AKR1B10. Accordingly, there is an ongoing search for selective AKR1B10 inhibitors that do not interact with endogeneous AKR1A1 and AKR1B1-driven detoxification systems. In this study, unisomerised α-acids (adhumulone, cohumulone and n-humulone) were separated and tested for their inhibitory potential on AKR1A1, AKR1B1 and AKR1B10. Also AKR1B10-mediated farnesal reduction was effectively inhibited by α-acid congeners with Ki-values ranging from 16.79 ± 1.33 µM (adhumulone) to 3.94 ± 0.33 µM (n-humulone). Overall, α-acids showed a strong inhibition with selectivity (115⁻137 fold) for AKR1B10. The results presented herein characterise hop-derived α-acids as a promising basis for the development of novel and selective AKR1B10-inhibitors.


Asunto(s)
Aldehído Reductasa/antagonistas & inhibidores , Ciclohexanonas/farmacología , Ciclohexenos/farmacología , Terpenos/farmacología , Aldehído Reductasa/metabolismo , Aldo-Ceto Reductasas , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Farnesol/análogos & derivados , Farnesol/química , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Humulus/química
10.
J Transl Med ; 15(1): 2, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-28049490

RESUMEN

BACKGROUND: Certain disadvantages of the standard hematopoietic stem and progenitor cell (HSPC) mobilizing agent G-CSF fuel the quest for alternatives. We herein report results of a Phase I dose escalation trial comparing mobilization with a peptidic CXCR4 antagonist POL6326 (balixafortide) vs. G-CSF. METHODS: Healthy male volunteer donors with a documented average mobilization response to G-CSF received, following ≥6 weeks wash-out, a 1-2 h infusion of 500-2500 µg/kg of balixafortide. Safety, tolerability, pharmacokinetics and pharmacodynamics were assessed. RESULTS: Balixafortide was well tolerated and rated favorably over G-CSF by subjects. At all doses tested balixafortide mobilized HSPC. In the dose range between 1500 and 2500 µg/kg mobilization was similar, reaching 38.2 ± 2.8 CD34 + cells/µL (mean ± SEM). Balixafortide caused mixed leukocytosis in the mid-20 K/µL range. B-lymphocytosis was more pronounced, whereas neutrophilia and monocytosis were markedly less accentuated with balixafortide compared to G-CSF. At the 24 h time point, leukocytes had largely normalized. CONCLUSIONS: Balixafortide is safe, well tolerated, and induces efficient mobilization of HSPCs in healthy male volunteers. Based on experience with current apheresis technology, the observed mobilization at doses ≥1500 µg/kg of balixafortide is predicted to yield in a single apheresis a standard dose of 4× 10E6 CD34+ cells/kg from most individuals donating for an approximately weight-matched recipient. Exploration of alternative dosing regimens may provide even higher mobilization responses. Trial Registration European Medicines Agency (EudraCT-Nr. 2011-003316-23) and clinicaltrials.gov (NCT01841476).


Asunto(s)
Voluntarios Sanos , Movilización de Célula Madre Hematopoyética , Péptidos Cíclicos/farmacología , Péptidos/farmacología , Receptores CXCR4/antagonistas & inhibidores , Diferenciación Celular/efectos de los fármacos , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Factor Estimulante de Colonias de Granulocitos/farmacología , Movilización de Célula Madre Hematopoyética/efectos adversos , Humanos , Masculino , Péptidos/farmacocinética , Péptidos Cíclicos/farmacocinética , Receptores CXCR4/metabolismo
11.
Eur J Haematol ; 99(1): 42-50, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28370401

RESUMEN

OBJECTIVE: Analysis of the efficiency and toxicity of cyclophosphamide-based stem cell mobilization in patients with relapsed multiple myeloma (RMM). METHODS: Peripheral blood stem cells (PBSCs) were mobilized with high dose cyclophosphamide (2 g/m2 daily on days 1 and 2) and G-CSF plus pre-emptive/rescue plerixafor in RMM patients (first to third relapse) treated within the ReLApsE trial of the German-Speaking Myeloma Multicenter Group (GMMG). RESULTS: Mobilization was initiated with high-dose cyclophosphamide (HD-CY) and G-CSF in 30 patients. Fifteen patients received additional pre-emptive/rescue administration of plerixafor. Stem cell collection was successful (≥2×106 CD34+ cells per kg bw) in 77% (23/30 patients). Patients with prior high-dose melphalan collected a significantly lower median total number of PBSCs than patients without prior high-dose melphalan (3.3×106 vs 17×106 CD34+ cells/kg bw). Toxicity of HD-CY was frequent with 12 serious adverse events (SAE) in 37% of patients (11/30 patients). Infections accounted for the majority of SAE reports. In two patients, SAEs were lethal (septic shock). CONCLUSIONS: These data proof feasibility of PBSC collection at relapse but emphasize the importance of collection and storage of additional PBSC transplants during first-line treatment when mobilization is more efficient and less toxic.


Asunto(s)
Ciclofosfamida/administración & dosificación , Movilización de Célula Madre Hematopoyética , Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple/patología , Mieloma Múltiple/terapia , Adulto , Anciano , Ciclofosfamida/efectos adversos , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/efectos adversos , Movilización de Célula Madre Hematopoyética/métodos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Células Madre de Sangre Periférica/citología , Células Madre de Sangre Periférica/efectos de los fármacos , Células Madre de Sangre Periférica/metabolismo , Recurrencia , Tiempo de Tratamiento , Trasplante Autólogo , Resultado del Tratamiento
12.
Toxicol Appl Pharmacol ; 293: 21-9, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26773812

RESUMEN

The clinical application of anthracyclines, like daunorubicin and doxorubicin, is limited by two factors: dose-related cardiotoxicity and drug resistance. Both have been linked to reductive metabolism of the parent drug to their metabolites daunorubicinol and doxorubicinol, respectively. These metabolites show significantly less anti-neoplastic properties as their parent drugs and accumulate in cardiac tissue leading to chronic cardiotoxicity. Therefore, we aimed to identify novel and potent natural inhibitors for anthracycline reductases, which enhance the anticancer effect of anthracyclines by preventing the development of anthracycline resistance. Human enzymes responsible for the reductive metabolism of daunorubicin were tested for their sensitivity towards anthrachinones, in particular emodin and anthraflavic acid. Intense inhibition kinetic data for the most effective daunorubicin reductases, including IC50- and Ki-values, the mode of inhibition, as well as molecular docking, were compiled. Subsequently, a cytotoxicity profile and the ability of emodin to reverse daunorubicin resistance were determined using multiresistant A549 lung cancer and HepG2 liver cancer cells. Emodin potently inhibited the four main human daunorubicin reductases in vitro. Further, we could demonstrate that emodin is able to synergistically sensitize human cancer cells towards daunorubicin at clinically relevant concentrations. Therefore, emodin may yield the potential to enhance the therapeutic effectiveness of anthracyclines by preventing anthracycline resistance via inhibition of the anthracycline reductases. In symphony with its known pharmacological properties, emodin might be a compound of particular interest in the management of anthracycline chemotherapy efficacy and their adverse effects.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Daunorrubicina/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Emodina/farmacología , Oxidorreductasas/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Antraquinonas/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Humanos , Simulación del Acoplamiento Molecular , Oxidorreductasas/metabolismo
13.
BMC Cancer ; 16: 290, 2016 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-27114074

RESUMEN

BACKGROUND: Despite novel therapeutic agents, most multiple myeloma (MM) patients eventually relapse. Two large phase III trials have shown significantly improved response rates (RR) of lenalidomide/dexamethasone compared with placebo/dexamethasone in relapsed MM (RMM) patients. These results have led to the approval of lenalidomide for RMM patients and lenalidomide/dexamethasone has since become a widely accepted second-line treatment. Furthermore, in RMM patients consolidation with high-dose chemotherapy plus autologous stem cell transplantation has been shown to significantly increase progression free survival (PFS) as compared to cyclophosphamide in a phase III trial. The randomized prospective ReLApsE trial is designed to evaluate PFS after lenalidomide/dexamethasone induction, high-dose chemotherapy consolidation plus autologous stem cell transplantation and lenalidomide maintenance compared with the well-established lenalidomide/dexamethasone regimen in RMM patients. METHODS/DESIGN: ReLApsE is a randomized, open, multicenter phase III trial in a planned study population of 282 RMM patients. All patients receive three lenalidomide/dexamethasone cycles and--in absence of available stem cells from earlier harvesting--undergo peripheral blood stem cell mobilization and harvesting. Subsequently, patients in arm A continue on consecutive lenalidomide/dexamethasone cycles, patients in arm B undergo high dose chemotherapy plus autologous stem cell transplantation followed by lenalidomide maintenance until discontinuation criteria are met. Therapeutic response is evaluated after the 3(rd) (arm A + B) and the 5(th) lenalidomide/dexamethasone cycle (arm A) or 2 months after autologous stem cell transplantation (arm B) and every 3 months thereafter (arm A + B). After finishing the study treatment, patients are followed up for survival and subsequent myeloma therapies. The expected trial duration is 6.25 years from first patient in to last patient out. The primary endpoint is PFS, secondary endpoints include overall survival (OS), RR, time to best response and the influence of early versus late salvage high dose chemotherapy plus autologous stem cell transplantation on OS. DISCUSSION: This phase III trial is designed to evaluate whether high dose chemotherapy plus autologous stem cell transplantation and lenalidomide maintenance after lenalidomide/dexamethasone induction improves PFS compared with the well-established continued lenalidomide/dexamethasone regimen in RMM patients. TRIAL REGISTRATION: ISRCTN16345835 (date of registration 2010-08-24).


Asunto(s)
Dexametasona/administración & dosificación , Mieloma Múltiple/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Talidomida/análogos & derivados , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Lenalidomida , Masculino , Persona de Mediana Edad , Mieloma Múltiple/patología , Recurrencia Local de Neoplasia/patología , Recurrencia , Terapia Recuperativa , Trasplante de Células Madre , Talidomida/administración & dosificación , Trasplante Autólogo
14.
FASEB J ; 29(1): 263-73, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25376835

RESUMEN

The purpose of this study was to investigate the origin and function of the aldo-keto reductase (AKR) superfamily as enzymes involved in the detoxification of xenobiotics. We used the cyanobacterium Synechocystis sp. PCC 6803 as a model organism and sequence alignments to find bacterial AKRs with highest identity to human enzymes. Disappearance of NADPH was monitored spectrophotometrically to calculate enzymatic activity. The molecular weight of the native protein was determined by size exclusion chromatography. Substrate docking was performed by SwissDock. Sequence alignments identified the NADPH-dependent AKR3G1 having 41.5 and 40% identity with the human enzymes AKR1B1 and AKR1B10, respectively. Highest enzymatic efficiency was observed with 4-oxonon-2-enal (4-ONE; k(cat)/K(m), 561 s(-1) mM(-1)) and 4-hydroxynonenal (k(cat)/K(m), 26.5 s(-1) mM(-1)), respectively. P74308 is the most efficient enzyme for 4-ONE discovered until now. Cooperativity of this monomeric enzyme was observed with some substrates. Enzyme inactivation or oligomerization as possible explanations for nonhyperbolic enzyme kinetics were ruled out by Selwyn's test and gel filtration. The role of the little investigated carbonyl-reducing enzymes in detoxification seems to be in fact a very old process with rarely observed nonhyperbolic enzyme kinetics as an adaptation mechanism to higher concentrations of reactive oxygen species.


Asunto(s)
Aldehído Reductasa/metabolismo , Proteínas Bacterianas/metabolismo , Synechocystis/enzimología , Aldehído Reductasa/química , Aldehído Reductasa/genética , Aldehídos/metabolismo , Aldo-Ceto Reductasas , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Dominio Catalítico , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Cinética , Ligandos , Peroxidación de Lípido , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Synechocystis/genética
15.
Ann Hematol ; 95(12): 1931-1942, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27696203

RESUMEN

The aim of this clinical trial was to evaluate the impact of all-trans retinoic acid (ATRA) in combination with chemotherapy and to assess the NPM1 status as biomarker for ATRA therapy in younger adult patients (18-60 years) with acute myeloid leukemia (AML). Patients were randomized for intensive chemotherapy with or without open-label ATRA (45 mg/m2, days 6-8; 15 mg/m2, days 9-21). Two cycles of induction therapy were followed by risk-adapted consolidation with high-dose cytarabine or allogeneic hematopoietic cell transplantation. Due to the open label character of the study, analysis was performed on an intention-to-treat (ITT) and a per-protocol (PP) basis. One thousand one hundred patients were randomized (556, STANDARD; 544, ATRA) with 38 patients treated vice versa. Median follow-up for survival was 5.2 years. ITT analyses revealed no difference between ATRA and STANDARD for the total cohort and for the subset of NPM1-mutated AML with respect to event-free (EFS; p = 0.93, p = 0.17) and overall survival (OS; p = 0.24 and p = 0.32, respectively). Pre-specified PP analyses revealed better EFS in NPM1-mutated AML (p = 0.05) and better OS in the total cohort (p = 0.03). Explorative subgroup analyses on an ITT basis revealed better OS (p = 0.05) in ATRA for genetic low-risk patients according to ELN recommendations. The clinical trial is registered at clinicaltrialsregister.eu (EudraCT Number: 2004-004321-95).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Quimioterapia de Inducción/métodos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamiento farmacológico , Tretinoina/administración & dosificación , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Quimioterapia de Inducción/mortalidad , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Nucleofosmina , Tasa de Supervivencia/tendencias , Resultado del Tratamiento , Adulto Joven
16.
Blood ; 120(12): 2521-8, 2012 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-22855604

RESUMEN

The European LeukemiaNet classification combines a heterogeneous group of aberrations as adverse-risk abnormalities. Our goal was to investigate the outcomes associated with distinct high-risk chromosomal abnormalities in acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (HSCT). We performed a retrospective cohort analysis in patients with high-risk AML who received first, HLA-compatible, allogeneic HSCT between January 2005 and December 2008. Data from 236 patients with a median age of 55 years were included. Because complex karyotype (CK), -5/5q-, and abnl(17p) are overlapping categories, a hierarchical classification system based on the presence or absence of abnl(17p) and -5/5q- was developed. Patients with abnl(17p) had a 2-year event-free survival (EFS) of 11% (95% confidence interval [CI], 0%-25%), patients with -5/5q- but no abnl(17p) a 2-year EFS of 29% (95% CI, 14%-44%), and patients with adverse-risk AML but neither of the 2 marker lesions a 2-year EFS of 49% (95% CI, 39%-59%). Notably, complex and monosomal karyotypes lost their prognostic value when these marker lesions were excluded. In conclusion, hierarchical classification of adverse-risk karyotypes by 2 marker lesions, abnl(17p) and -5/5q-, is effective in prognostication of the outcome of allogeneic HSCT in AML.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 17/genética , Cromosomas Humanos Par 5/genética , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Adulto , Anciano , Femenino , Antígenos HLA , Humanos , Cariotipificación , Leucemia Mieloide Aguda/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Trasplante Homólogo , Adulto Joven
17.
Blood ; 119(4): 940-8, 2012 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-22160383

RESUMEN

In patients with multiple myeloma (MM), risk stratification by chromosomal abnormalities may enable a more rational selection of therapeutic approaches. In the present study, we analyzed the prognostic value of 12 chromosomal abnormalities in a series of 354 MM patients treated within the HOVON-65/GMMG-HD4 trial. Because of the 2-arm design of the study, we were able to analyze the effect of a bortezomib-based treatment before and after autologous stem cell transplantation (arm B) compared with standard treatment without bortezomib (arm A). For allanalyzed chromosomal aberrations, progression-free survival (PFS) and overall survival (OS) were at least equal or superior in the bortezomib arm compared with the standard arm. Strikingly, patients with del(17p13) benefited the most from the bortezomib-containing treatment: the median PFS in arm A was 12.0 months and in arm B it was 26.2 months (P = .024); the 3 year-OS for arm A was 17% and for arm B it was 69% (P = .028). After multivariate analysis, del(17p13) was an independent predictor for PFS (P < .0001) and OS (P < .0001) in arm A, whereas no statistically significant effect on PFS (P = .28) or OS (P = .12) was seen in arm B. In conclusion, the adverse impact of del(17p13) on PFS and OS could be significantly reduced by bortezomib-based treatment, suggesting that long-term administration of bortezomib should be recommended for patients carrying del(17p13).


Asunto(s)
Antineoplásicos/uso terapéutico , Ácidos Borónicos/uso terapéutico , Quimioterapia de Inducción , Quimioterapia de Mantención , Mieloma Múltiple/tratamiento farmacológico , Pirazinas/uso terapéutico , Trasplante de Células Madre , Adolescente , Adulto , Anciano , Bortezomib , Aberraciones Cromosómicas , Deleción Cromosómica , Cromosomas Humanos Par 17/genética , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/genética , Mieloma Múltiple/terapia , Pronóstico , Síndrome de Smith-Magenis , Análisis de Supervivencia , Trasplante Autólogo , Adulto Joven
18.
Haematologica ; 99(1): 148-54, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23996482

RESUMEN

Renal impairment is frequent in patients with multiple myeloma and is correlated with an inferior prognosis. This analysis evaluates the prognostic role of renal impairment in patients with myeloma treated with bortezomib before and after autologous stem cell transplantation within a prospective randomized phase III trial. Eight hundred and twenty-seven newly diagnosed myeloma patients in the HOVON-65/GMMG-HD4 trial were randomized to receive three cycles of vincristine, adriamycin, dexamethasone (VAD) or bortezomib, adriamycin, dexamethasone (PAD) followed by autologous stem cell transplantation and maintenance with thalidomide 50 mg daily (VAD-arm) or bortezomib 1.3 mg/m(2) every 2 weeks (PAD-arm). Baseline serum creatinine was less than 2 mg/dL (Durie-Salmon-stage A) in 746 patients and 2 mg/dL or higher (stage B) in 81. In myeloma patients with a baseline creatinine ≥ 2 mg/dL the renal response rate was 63% in the VAD-arm and 81% in the PAD-arm (P=0.31). The overall myeloma response rate was 64% in the VAD-arm versus 89% in the PAD-arm with 13% complete responses in the VAD-arm versus 36% in the PAD-arm (P=0.01). Overall survival at 3 years for patients with a baseline creatinine ≥ 2 mg/dL was 34% in the VAD-arm versus 74% in the PAD-arm (P<0.001) with a progression-free survival rate at 3 years of 16% in the VAD-arm versus 48% in the PAD-arm (P=0.004). Overall and progression-free survival rates in the PAD-arm were similar in patients with a baseline creatinine ≥ 2 mg/dL or <2 mg/dL. We conclude that a bortezomib-containing treatment before and after autologous stem cell transplantation overcomes the negative prognostic impact of renal impairment in patients with newly diagnosed multiple myeloma. The trial was registered at www.trialregister.nl as NTR213 and at www.controlled-trials.com as ISRCTN 64455289.


Asunto(s)
Antineoplásicos/uso terapéutico , Ácidos Borónicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple/complicaciones , Mieloma Múltiple/terapia , Pirazinas/uso terapéutico , Insuficiencia Renal/etiología , Insuficiencia Renal/prevención & control , Adulto , Anciano , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Ácidos Borónicos/administración & dosificación , Ácidos Borónicos/efectos adversos , Bortezomib , Creatinina/sangre , Humanos , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Pirazinas/administración & dosificación , Pirazinas/efectos adversos , Inducción de Remisión , Insuficiencia Renal/mortalidad , Insuficiencia Renal/fisiopatología , Trasplante Autólogo , Resultado del Tratamiento
19.
Leukemia ; 37(2): 465-472, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36550212

RESUMEN

Blastic plasmacytoid dendritic cell neoplasia (BPDCN) is a rare myeloid malignancy with a generally poor prognosis. Although preliminary evidence suggests that hematopoietic cell transplantation (HCT) could improve outcome in patients with BPDCN, the individual contributions of conditioning and graft-versus-tumor (GVT) effects to HCT success are undefined. We present a retrospective study of 162 adult patients who underwent a first HCT (allogeneic 146, autologous 16) between 2009 and 2017, and were registered with the EBMT. Median age was 57 (range 20-73) years, and disease status at HCT was first complete remission (CR1) in 78%. Among patients receiving allogeneic HCT (alloHCT), myeloablative conditioning (MAC), reduced intensity conditioning (RIC) and in-vivo T-cell depletion (TCD) were used in 54%, 46%, and 59% respectively. Total body irradiation (TBI) was the conditioning backbone in 61% of MAC and 26% of RIC transplants. One-year overall survival (OS) and progression-free survival (PFS) rates were comparable after alloHCT and autologous HCT (autoHCT). Among alloHCT recipients, MAC with TBI significantly improved OS and PFS, independently of CR1, age, Karnofsky index and TCD. Accordingly, MAC (ideally based on TBI) should be preferred for alloHCT recipients with BPDCN. In patients who are not elegible for MAC alloHCT, autoHCT could be considered.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Trastornos Mieloproliferativos , Neoplasias Cutáneas , Adulto , Anciano , Humanos , Persona de Mediana Edad , Adulto Joven , Enfermedad Aguda , Células Dendríticas/patología , Trastornos Mieloproliferativos/patología , Recurrencia Local de Neoplasia/patología , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Acondicionamiento Pretrasplante , Resultado del Tratamiento
20.
Ecology ; 103(5): e3652, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35084736

RESUMEN

Migration is a tactic used across taxa to access resources in temporally heterogenous landscapes. Populations that migrate can attain higher abundances because such movements allow access to higher quality resources, or reduction in predation risk resulting in increased fitness. However, most migratory species occur in partially migratory populations, a mix of migratory and non-migratory individuals. It is thought that the portion of migrants in a partial migration population is maintained either through (1) a population-level evolutionary stable state where counteracting density-dependent vital rates act on migrants and residents to balance fitness or (2) conditional migration, where the propensity to migrate is influenced by the individual's state. However, in many respects, migration is also a form of habitat selection and the proportion of migrants and residents may be the result of density-dependent habitat selection. Here, we test whether the theory of Ideal Free Distribution (IFD) can explain the coexistence of different migratory tactics in a partially migratory population. IFD predicts individuals exhibit density-dependent vital rates and select different migratory tactics to maximize individual fitness resulting in equal fitness (λ) between tactics. We tested the predictions of IFD in a partially migratory elk population that declined by 70% with 19 years of demographic data and migratory tactic switching rates from >300 individuals. We found evidence of density dependence for resident pregnancy and adult female survival providing a fitness incentive to switch tactics. Despite differences in vital rates between migratory tactics, mean λ (fitness) was equal. However, as predicted by the IFD, individuals switched tactics toward those of higher fitness. Our analysis reveals that partial migration may be driven by tactic selection that follows the ideal free distribution. These findings reinforce that migration across taxa may be a polymorphic behavior in large herbivores where migratory tactic selection is determined by differential costs and benefits, mediated by density dependence.


Asunto(s)
Migración Animal , Herbivoria , Animales , Ecosistema , Femenino , Densidad de Población , Conducta Predatoria
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