Spectroscopic, calorimetric and cytotoxicity studies on the combined binding of daunorubicin and acridine orange to a DNA tetrahedron.

Chemotherapy-phototherapy (CTPT) combination drugs co-loaded by targeted DNA nanostructures can achieve controlled drug delivery, reduce toxic side effects and overcome multidrug resistance. Herein, we constructed and characterized a DNA tetrahedral nanostructure (MUC1-TD) linked with the targeting aptamer MUC1. The interaction of daunorubicin (DAU)/acridine orange (AO) alone and in combination with MUC1-TD and the influence of the interaction on the cytotoxicity of the drugs were evaluated. Potassium ferrocyanide quenching analysis and DNA melting temperature assays were used to demonstrate the intercalative binding of DAU/AO to MUC1-TD. The interactions of DAU and/or AO with MUC1-TD were analyzed by fluorescence spectroscopy and differential scanning calorimetry. The number of binding sites, binding constant, entropy and enthalpy changes of the binding process were obtained. The binding strength and binding sites of DAU were higher than those of AO. The presence of AO in the ternary system weakened the binding of DAU to MUC1-TD. In vitro cytotoxicity studies demonstrated that the loading of MUC1-TD augmented the inhibitory effects of DAU and AO and the synergistic cytotoxic effects of DAU + AO on MCF-7 cells and MCF-7/ADR cells. Cell uptake studies showed that the loading of MUC1-TD was beneficial in promoting the apoptosis of MCF-7/ADR cells due to its enhanced targeting to the nucleus. This study has important guiding significance for the combined application of DAU and AO co-loaded by DNA nanostructures to overcome multidrug resistance.

Alterations in sphingolipid composition and mitochondrial bioenergetics represent synergistic therapeutic vulnerabilities linked to multidrug resistance in leukemia.

Modifications in sphingolipid (SL) metabolism and mitochondrial bioenergetics are key factors implicated in cancer cell response to chemotherapy, including chemotherapy resistance. In the present work, we utilized acute myeloid leukemia (AML) cell lines, selected to be refractory to various chemotherapeutics, to explore the interplay between SL metabolism and mitochondrial biology supportive of multidrug resistance (MDR). In agreement with previous findings in cytarabine or daunorubicin resistant AML cells, relative to chemosensitive wildtype controls, HL-60 cells refractory to vincristine (HL60/VCR) presented with alterations in SL enzyme expression and lipidome composition. Such changes were typified by upregulated expression of various ceramide detoxifying enzymes, as well as corresponding shifts in ceramide, glucosylceramide, and sphingomyelin (SM) molecular species. With respect to mitochondria, despite consistent increases in both basal respiration and maximal respiratory capacity, direct interrogation of the oxidative phosphorylation (OXPHOS) system revealed intrinsic deficiencies in HL60/VCR, as well as across multiple MDR model systems. Based on the apparent requirement for augmented SL and mitochondrial flux to support the MDR phenotype, we explored a combinatorial therapeutic paradigm designed to target each pathway. Remarkably, despite minimal cytotoxicity in peripheral blood mononuclear cells (PBMC), co-targeting SL metabolism, and respiratory complex I (CI) induced synergistic cytotoxicity consistently across multiple MDR leukemia models. Together, these data underscore the intimate connection between cellular sphingolipids and mitochondrial metabolism and suggest that pharmacological intervention across both pathways may represent a novel treatment strategy against MDR.

Self-Assembled Daunorubicin/Epigallocatechin Gallate Nanocomplex for Synergistic Reversal of Chemoresistance in Leukemia.

Chemoresistance is one of the major challenges for the treatment of acute myeloid leukemia. Epigallocatechin gallate (EGCG), a bioactive polyphenol from green tea, has attracted immense interest as a potential chemosensitizer, but its application is limited due to the need for effective formulations capable of co-delivering EGCG and anti-leukemic drugs. Herein, we describe the formation and characterization of a micellar nanocomplex self-assembled from EGCG and daunorubicin, an anthracycline drug for the first-line treatment of acute myeloid leukemia. This nanocomplex was highly stable at pH 7.4 but stimulated to release the incorporated daunorubicin at pH 5.5, mimicking an acidic endosomal environment. More importantly, the nanocomplex exhibited superior cytotoxic efficacy against multidrug-resistant human leukemia cells over free daunorubicin by achieving a strong synergism, as supported by median-effect plot analysis. The observed chemosensitizing effect was in association with enhanced nucleus accumulation of daunorubicin, elevation of intracellular reactive oxygen species and caspase-mediated apoptosis induction. Our study presents a promising strategy for circumventing chemoresistance for more effective leukemia therapy.

Is there an optimal adjunct therapy to traditional cytotoxic induction?

The traditional cytotoxic induction regimen for acute myeloid leukemia (AML) is seven days of standard-dose cytarabine and three days of an anthracycline antibiotic (such as daunorubicin or idarubicin), commonly known as "7 + 3." Many studies have been conducted to find an additional agent that might improve efficacy. Data from select studies has shown, in certain populations, benefit to adding cladribine, clofarabine and lomustine to a traditional backbone. For mutation-based chemotherapy regimens, midostaurin with 7 + 3 is the current standard of care for FLT3-mutant, younger AML patients. As we learn more about the synergism of molecular agents and traditional anti-cancer treatments, we can hopefully develop novel regimens without abandoning some of the benefits of these mutation agnostic historical therapies.

Acute myeloid leukemia: Treatment and research outlook for 2021 and the MD Anderson approach.

The unraveling of the pathophysiology of acute myeloid leukemia (AML) has resulted in rapid translation of the information into clinical practice. After more than 40 years of slow progress in AML research, the US Food and Drug Administration has approved nine agents for different AML treatment indications since 2017. In this review, we detail the progress that has been made in the research and treatment of AML, citing key publications related to AML research and therapy in the English literature since 2000. The notable subsets of AML include acute promyelocytic leukemia (APL), core-binding factor AML (CBF-AML), AML in younger patients fit for intensive chemotherapy, and AML in older/unfit patients (usually at the age cutoff of 60-70 years). We also consider within each subset whether the AML is primary or secondary (therapy-related, evolving from untreated or treated myelodysplastic syndrome or myeloproliferative neoplasm). In APL, therapy with all-trans retinoic acid and arsenic trioxide results in estimated 10-year survival rates of ≥80%. Treatment of CBF-AML with fludarabine, high-dose cytarabine, and gemtuzumab ozogamicin (GO) results in estimated 10-year survival rates of ≥75%. In younger/fit patients, the "3+7" regimen (3 days of daunorubicin + 7 days of cytarabine) produces less favorable results (estimated 5-year survival rates of 35%; worse in real-world experience); regimens that incorporate high-dose cytarabine, adenosine nucleoside analogs, and GO are producing better results. Adding venetoclax, FLT3, and IDH inhibitors into these regimens has resulted in encouraging preliminary data. In older/unfit patients, low-intensity therapy with hypomethylating agents (HMAs) and venetoclax is now the new standard of care. Better low-intensity regimens incorporating cladribine, low-dose cytarabine, and other targeted therapies (FLT3 and IDH inhibitors) are emerging. Maintenance therapy now has a definite role in the treatment of AML, and oral HMAs with potential treatment benefits are also available. In conclusion, AML therapy is evolving rapidly and treatment results are improving in all AML subsets as novel agents and strategies are incorporated into traditional AML chemotherapy. LAY SUMMARY: Ongoing research in acute myeloid leukemia (AML) is progressing rapidly. Since 2017, the US Food and Drug Administration has approved 10 drugs for different AML indications. This review updates the research and treatment pathways for AML.

Gemtuzumab ozogamicin in acute myeloid leukemia: past, present and future.

After being in the therapeutic wilderness for several decades, acute myeloid leukemia has been recently thrust into the limelight with a series of drug approvals. Technical refinements in production, genetic manipulation and chemical modification of monoclonal antibodies led to growing interest in antibodies-based treatment strategies. Much of the focus of these efforts in acute myeloid leukemia has been on CD33 as a target. On September 2, 2017, the U.S. Food and Drug Administration approved gemtuzumab ozogamicin for treatment of relapsed or refractory CD33+ acute myeloid leukemia. This signals a new chapter in the long and unusual story of gemtuzumab ozogamicin, which was the first antibody-drug conjugate approved for human use by the Food and Drug Administration. In this review we have analyzed the history of this drug which, among several mishaps, is experiencing a second youth and still represents a field to be further explored.

The epigallocatechin gallate derivative Y6 reduces the cardiotoxicity and enhances the efficacy of daunorubicin against human hepatocellular carcinoma by inhibiting carbonyl reductase 1 expression.

ETHNOPHARMACOLOGICAL RELEVANCE: Green tea is the most ancient and popular beverage worldwide and its main constituent epigallocatechin-3-gallate (EGCG) has a potential role in the management of cancer through the modulation of cell signaling pathways. However, EGCG is frangible to oxidation and exhibits low lipid solubility and bioavailability, and we synthesized a derivative of EGCG in an attempt to overcome these limitations. AIM OF THE STUDY: The anthracycline antibiotic daunorubicin (DNR) is a potent anticancer agent. However, its severe cardiotoxic limits its clinical efficacy. Human carbonyl reductase 1 (CBR1) is one of the most effective human reductases for producing hydroxyl metabolites and thus may be involved in increasing the cardiotoxicity and decreasing the antineoplastic effect of anthracycline antibiotics. Accordingly, in this study, we investigated the co-therapeutic effect of Y6, a novel and potent adjuvant obtained by optimization of the structure of EGCG. MATERIAL AND METHODS: The cellular concentrations of DNR and its metabolite DNRol were measured by HPLC to determine the effects of EGCG and Y6 on the inhibition of DNRol formation. The cytotoxic effects of EGCG and Y6 were tested by MTT assay in order to identify non-toxic concentrations of them. To understand their antitumor and cardioprotective mechanisms, hypoxia-inducible factor-1α (HIF-1α) and CBR1 protein expression was measured via Western blotting and immunohistochemical staining while gene expression was analyzed using RT-PCR. Moreover, PI3K/AKT and MEK/ERK signaling pathways were analyzed via Western blotting. HepG2 xenograft model was used to detect the effects of EGCG and Y6 on the antitumor activity and cardiotoxicity of DNR in vivo. Finally, to obtain further insight into the interactions of Y6 and EGCG with HIF-1α and CBR1, we performed a molecular modeling. RESULTS: Y6(10 µg/ml or 55 mg/kg) decreased the expression of HIF-1α and CBR1 at both the mRNA and protein levels during combined drug therapy in vitro as well as in vivo, thereby inhibiting formation of the metabolite DNRol from DNR, with the mechanisms being related to PI3K/AKT and MEK/ERK signaling inhibition. In a human carcinoma xenograft model established with subcutaneous HepG2 cells, Y6(55 mg/kg) enhanced the antitumor effect and reduced the cardiotoxicity of DNR more effectively than EGCG(40 mg/kg). CONCLUSIONS: Y6 has the ability to inhibit CBR1 expression through the coordinate inhibition of PI3K/AKT and MEK/ERK signaling, then synergistically enhances the antitumor effect and reduces the cardiotoxicity of DNR.

Hexokinase II inhibition by 3-bromopyruvate sensitizes myeloid leukemic cells K-562 to anti-leukemic drug, daunorubicin.

An increased metabolic flux towards Warburg phenotype promotes survival, proliferation and causes therapeutic resistance, in leukemic cells. Hexokinase-II (HK-II) is expressed predominantly in cancer cells, which promotes Warburg metabolic phenotype and protects the cancer cells from drug-induced apoptosis. The HK-II inhibitor 3- Bromopyruvate (3-BP) dissociates HK-II from mitochondrial complex, which leads to enhanced sensitization of leukemic cells to anti-leukemic drugs. In the present study, we analyzed the Warburg characteristics viz. HK-II expression, glucose uptake, endogenous reactive oxygen species (ROS) level of leukemic cell lines K-562 and THP-1 and then investigated if 3-BP can sensitize the leukemic cells K-562 to anti-leukemic drug Daunorubicin (DNR). We found that both K-562 and THP-1 cells have multi-fold high levels of HK-II, glucose uptake and endogenous ROS with respect to normal PBMCs. The combined treatment (CT) of 3-BP and DNR showed synergistic effect on the growth inhibition (GI) of K-562 and THP-1 cells. This growth inhibitory effect was attributed to 3-BP induced S-phase block and DNR induced G2/M block, resulted in reduced proliferation due to CT. Further, CT resulted in low HK-II level in mitochondrial fraction, high intracellular calcium and elevated apoptosis as compared with individual treatment of DNR and 3-BP. Moreover, CT caused enhanced DNA damage and hyperpolarized mitochondria, leading to cell death. Taken together, these results suggest that 3-BP synergises the anticancer effects of DNR in the chronic myeloid leukemic cell K-562, and may act as an effective adjuvant to anti-leukemic chemotherapy.

Análisis de impacto presupuestal de tecnologías para el manejo complementario de quimioterapia en Colombia / Budget impact analysis of technologies for the complementary management of chemotherapy in Colombia

INTRODUCCIÓN: El análisis de impacto presupuestal (AIP) de los medicamentos quimioterapéuticos para el tratamiento de cáncer en Colombia, se desarrolló en el marco del mecanismo técnico científico para la ampliación progresiva del Plan de Beneficios en Salud con cargo a la UPC (PBSUPC) y la definición de la lista de exclusiones, establecido en el artículo 15 de la Ley 1751 de 2015. La quimioterapia tiene un gran impacto en el tratamiento oncológico, la cual es indispensable por su valor terapéutico en varios tipos de cáncer. Esta tecnología puede ser usada sola o junto con otros tratamientos, tales como la cirugía o la radioterapia. La quimioterapia engloba a una gran variedad de fármacos y su objetivo es destruir las células tumorales con el fin de lograr la reducción de la enfermedad, los medicamentos empleados en este tipo de tratamiento se les denomina fármacos antineoplásicos. Cada tipo de tumor canceroso tiene una determinada sensibilidad a estos medicamentos, por lo tanto, es frecuente que el mismo fármaco se pueda emplear en el tratamiento de distintos tumores, variando las dosis o asociándolo a otros fármacos distintos. La quimioterapia puede ser administrada con fines curativos o para aliviar los síntomas y prolongar la supervivencia. La forma de administración de la quimioterapia es por ciclos y esto se logra alternando los periodos de tratamiento con periodos de descanso. Un ciclo es, por lo tanto, el periodo de administración del tratamiento y el de descanso hasta la siguiente administración. El objetivo de este análisis de impacto presupuestal (AIP) es estimar el esfuerzo financiero necesario para la adopción de la quimioterapia en el tratamiento de pacientes con cáncer en Colombia, en un horizonte temporal de tres años. Este documento está conformado por cuatro secciones: en la primera se identifican las tecnologías a evaluar, en la segunda sección se especifica la perspectiva, horizonte temporal y la población sobre la cual se realizó el AIP; en la sección tres se detallan los costos utilizados en el modelo, además de los escenarios planteados por los investigadores; por último, en la sección cuatro se exponen los resultados en los diferentes escenarios planteados Este documento describe la metodología desarrollada para realizar el análisis de impacto presupuestal de 21 tecnologías para el manejo quimioterapéutico del cáncer en Colombia Este informe, sigue los lineamientos propuestos en el Manual para la Elaboración de Análisis de Impacto Presupuestal y en Manual de Participación y Deliberación publicados por IETS. Insumos y método: Esta sección presenta los supuestos, parámetros y métodos utilizados para el modelo de estimación del impacto presupuestal describiendo la siguiente información: Perspectiva: La perspectiva de este AIP es la del tercer pagador el cual en nuestro contexto es el Sistema General de Seguridad Social en Salud (SGSSS). Horizonte temporal: El horizonte temporal de este AIP en el caso base corresponde a un año. Adicionalmente se reportan las estimaciones del impacto presupuestal para los años 2 y 3, bajo el supuesto de inclusión en el PBS en el año 1. Población total: Para el desarrollo de este AIP se parte de la población general afiliada al SGSSS colombiano sin distinción de sexo o edad. ESCENARIOS: Se consideró para la formulación de los escenarios de adopción de las tecnologías evaluadas los siguientes aspectos: 1. Los medicamentos evaluados no son alternativas terapéuticas para las patologías observadas, estas tecnologías sanitarias hacen parte de los protocolos de tratamiento con evidencia científica suficiente que garantizan su efectividad y seguridad clínica y que actualmente se encuentran en las opciones de tratamiento utilizados en la práctica clínica colombiana. 2. Al ser esquemas de tratamiento que hacen parte de protocolos estandarizados de aplicación, sí alguno de los medicamentos es sujeto de recobros ante ADRES, este trámite puede generar barreras de acceso al tratamiento hasta que se efectué la respectiva aprobación. Por lo tanto, no hay certeza de la efectividad clínica si los esquemas de tratamiento son suministrados de forma parcial o incompleta. 3. La elección del esquema de tratamiento obedece a criterios clínicos y a las características evaluadas en el paciente, no se espera una sustitución entre los diferentes esquemas sí se realiza un cambio en el mecanismo de financiamiento. 4. La adopción de las tecnologías evaluadas en este AIP no se espera que se modifiquen de manera importante, debido a que estas tecnologías hacen parte integral de los esquemas de tratamiento y su incorporación en la práctica clínica habitual en el contexto internacional y nacional, data de aproximadamente 10 a 5 años. Tambieén son parte de las opciones de primera línea de tratamiento para estadios tempranos, avanzados y localmente avanzados del paciente diagnosticado con câncer. De acuerdo a las anteriores consideraciones, al incorporar los medicamentos evaluados al PBS con cargo a la UPC, se espera la misma composición del mercado con la adopción de los nuevos medicamentos en el 100% de los tratamientos esperados en la siguiente anualidad. Los resultados esperados en el sistema de salud, en este cambio de financiamiento, se esperan obtener en dos puntos: a) En una mejor oportunidad de acceso a los esquemas de tratamiento en el SGSSS (25). b) En una mejora en la cobertura efectiva de los tratamientos de quimioterapia en pacientes con diagnóstico de cáncer. RESULTADOS: Se muestra el resultado consolidado para las ventiun tecnologías objeto del Análisis de Impacto Presupuestal. La tecnología que genera un mayor impacto es Oxaliplatino, con un valor por persona de $2.363.250,76 usada en 3170 pacientes, para un total de $7.491.504.923,90. El Megestrol es la tecnología con menor impacto, con un costo por persona de $ 383.791,06 y siendo usada en 34 pacientes, tiene un valor total de $ 13.048.896,00. La tretinoina es la tecnología más económica por paciente, con un valor de $ 97.996,50, es usada en 242 personas para un total de $ 23.715.153,00. DISCUSIÓN: En la práctica actual existe un volumen amplio de recobros en el caso de estos medicamentos por usos UNIRS. En algunos casos, los cambios en el mercado farmacéutico, ya sea por el retiro de medicamentos o la llegada de ellos, hace que se modifique indicaciones ya existentes en los registros y que pueden llegar a impactar estos. usos, por ejemplo aquellos casos en los que existe la indicación antineplásico y se cambian por indicaciones especificas, que pueden no considerar condiciones de salud de baja incidencia. Como se ha caracterizado con anterioridad, el mercado de tecnologías sanitarias que se encuentran incluidas al plan de beneficios en salud con cargo a la UPC difiere sustancialmente al mercado de tecnologías sanitarias aún no financiadas por dicho mecanismo. La existencia de las Empresas Administradoras de Planes de Beneficios (EAPB) presume la existencia de un actor que al maximizar su beneficio, es un buen negociador que en cumplimiento de los principios del SGSSS, llega a un precio de equilibrio que maximiza el beneficio social. En cambio, los medicamentos que son sujetos a recobros al ADRES presume un precio fuera de aquel nivel en donde se maximiza al beneficio social, en la medida que no hay una función clara de monopsonio que coteje y negocie un precio de adquisición. En algunos casos puede llegar asumir sobrecostos que las EAPB al ser intermediarias, no tienen incentivos para efectuar un adecuado control. Con el objetivo de estimar el resultado de la incorporación de estos medicamentos al PBS con cargo a la UPC, se asumieron dos escenarios en los cuales la población objetivo del AIP se consideró constante y se asumieron los siguientes supuestos: En el primer escenario se asume que los precios observados en recobros serán el promedio de todas las transacciones de compra en la siguiente anualidad. En el segundo escenario los precios promedio de adquisición de los medicamentos evaluados, corresponden al promedio observado en SISMED como predictor de los precios de equilibrio que pueden generar las EAPB como ente negociador. Se asume que, en promedio, las EAPB son negociadores eficientes que se acercan a un precio de equilibrio que maximiza el bienestar social. Se asume que la población objetivo corresponde al total de posibles pacientes que requieren las tecnologías sanitarias en evaluación, sin que exista demanda insatisfecha para estos esquemas de tratamiento. Para su cálculo, como se presenta en la tabla 09 de los servicios prestados durante el año 2015 y recobrados al FOSYGA en los años 2015 y 2016, se calculó un valor per-cápita de acuerdo con el identificador (cedula de ciudadanía anonimizada) registrado en cada recobro. Luego, este valor es indexado a precios 2016 con el IPC reportado por el DANE a diciembre 31 del año 2015. Este valor será el comparador del precio calculado para cada uno de los medicamentos a partir de SISMED 2016.

Alternative pre-approved and novel therapies for the treatment of anthrax.

BACKGROUND: Bacillus anthracis, the causative agent of anthrax, is a spore forming and toxin producing rod-shaped bacterium that is classified as a category A bioterror agent. This pathogenic microbe can be transmitted to both animals and humans. Clinical presentation depends on the route of entry (direct contact, ingestion, injection or aerosolization) with symptoms ranging from isolated skin infections to more severe manifestations such as cardiac or pulmonary shock, meningitis, and death. To date, anthrax is treatable if antibiotics are administered promptly and continued for 60 days. However, if treatment is delayed or administered improperly, the patient's chances of survival are decreased drastically. In addition, antibiotics are ineffective against the harmful anthrax toxins and spores. Therefore, alternative therapeutics are essential. In this review article, we explore and discuss advances that have been made in anthrax therapy with a primary focus on alternative pre-approved and novel antibiotics as well as anti-toxin therapies. METHODS: A literature search was conducted using the University of Manitoba search engine. Using this search engine allowed access to a greater variety of journals/articles that would have otherwise been restricted for general use. In order to be considered for discussion for this review, all articles must have been published later than 2009. RESULTS: The alternative pre-approved antibiotics demonstrated high efficacy against B. anthracis both in vitro and in vivo. In addition, the safety profile and clinical pharmacology of these drugs were already known. Compounds that targeted underexploited bacterial processes (DNA replication, RNA synthesis, and cell division) were also very effective in combatting B. anthracis. In addition, these novel compounds prevented bacterial resistance. Targeting B. anthracis virulence, more specifically the anthrax toxins, increased the length of which treatment could be administered. CONCLUSIONS: Several novel and pre-existing antibiotics, as well as toxin inhibitors, have shown increasing promise. A combination treatment that targets both bacterial growth and toxin production would be ideal and probably necessary for effectively combatting this armed bacterium.

Overcoming chemoresistance in prostate cancer with Chinese medicine Tripterygium wilfordii via multiple mechanisms.

A leading cause of cancer chemotherapy failure is chemoresistance, which often involves multiple mechanisms. Chinese medicines (CM) usually contain multiple components which could potentially target many mechanisms simultaneously and may offer an advantage over single compounds that target one mechanism at a time. The purpose of this study was to investigate the chemosensitizing effect (CE) of a specific CM, Tripterygium wilfordii (TW), on prostate cancer cells resistant to docetaxel (Dtx) and identify the potential mechanisms. The CE of TW (in combination with Dtx) was evaluated in two Dtx resistant prostate cancer cell lines (PC3-TxR and DU145-TxR) and the efficacy of the combination for resistant PC3-TxR tumor was investigated using a xenograft mouse model. For mechanistic study, the inhibitory effect of TW on P-glycoprotein activity was assessed. In addition, novel gene targets of TW were identified using DNA microarray and quantitative PCR. Results showed that TW induced a CE of 8 and >38 folds in PC3-TxR and DU145-TxR cells, respectively with Dtx IC50 reversed back to that of the sensitive parent cells. An optimum dose of TW+Dtx significantly retarded tumor growth in mice compared to TW or Dtx alone. TW inhibited P-glycoprotein activity and induced a significant gene expression changes in genes related to angiogenesis, cell cycle regulation and differentiation. Our in vitro and in vivo studies demonstrate that TW in combination with Dtx was able to overcome the chemoresistance and suppress resistant prostate tumor growth via multi-mechanisms.

Lecithin and PLGA-based self-assembled nanocomposite, Lecithmer: preparation, characterization, and pharmacokinetic/pharmacodynamic evaluation.

The present study investigates the drug delivery potential of polymer lipid hybrid nanocomposites (Lecithmer®) composed of poly(D,L-lactide-co-glycolide (PLGA) and soya lecithin. Core-shell structure of Lecithmer was evident from cryo-TEM images. Daunorubicin (DNR) and lornoxicam (LNX)-incorporated Lecithmer nanocomposites were evaluated for anticancer and anti-inflammatory activity. DNR- and LNX-loaded Lecithmer had mean particle size of ∼335 and ∼282.7 nm, respectively. Lecithmer formulated with different cationic lipids resulted in lower particle size (∼120 nm) and positive zeta potential. Entrapment efficiency of DNR and LNX was 93.16 and 88.59 %, respectively. In vitro release of DNR from Lecithmer was slower compared to PLGA nanoparticles. DNR release from Lecithmer was significantly higher at pH 5.5 (80.96 %) as compared to pH 7.4 (55.95 %), providing advantage for selective tumor therapy. Similarly, sustained release of LNX (30 % in 10 h) was observed at pH 7.4. DNR in Lecithmer showed superior cytotoxicity on human erythroleukemic K562 cells. Pharmacokinetic study in Wistar rats with i.v. administered DNR-loaded Lecithmer showed higher volume of distribution, lower elimination rate constant, and longer half-life (81.68 L, 0.3535 h(-1), 1.96 h) as compared to DNR solution (57.46 L, 0.4237 h(-1), 1.635 h). Pharmacodynamic evaluation of orally administered LNX-loaded Lecithmer showed superior anti-inflammatory activity with maximum inhibition of 81.2 % vis-à-vis 53.57 % in case of LNX suspension. In light of these results, Lecithmer can be envisaged as a promising nanosystem for parenteral as well as oral drug delivery.

Pyrrolopyrimidine Derivatives as Novel Inhibitors of Multidrug Resistance-Associated Protein 1 (MRP1, ABCC1).

Five series of pyrrolo[3,2-d]pyrimidines were synthesized and evaluated with respect to potency and selectivity toward multidrug resistance-associated protein 1 (MRP1, ABCC1). This transport protein is a major target to overcome multidrug resistance in cancer patients. We investigated differently substituted pyrrolopyrimidines using the doxorubicin selected and MRP1 overexpressing small cell lung cancer cell line H69 AR in a calcein AM and daunorubicin cell accumulation assay. New compounds with high potency and selectivity were identified. Piperazine residues at position 4 bearing large phenylalkyl side chains proved to be beneficial for MRP1 inhibition. Its replacement by an amino group led to decreased activity. Aliphatic and aliphatic-aromatic variations at position 5 and 6 revealed compounds with IC50 values in high nanomolar range. All investigated compounds had low affinity toward P-glycoprotein (P-gp, ABCB1). Pyrrolopyrimidines with small substituents showed moderate inhibition against breast cancer resistance protein (BCRP, ABCG2).

Identification of genomic biomarkers for anthracycline-induced cardiotoxicity in human iPSC-derived cardiomyocytes: an in vitro repeated exposure toxicity approach for safety assessment.

The currently available techniques for the safety evaluation of candidate drugs are usually cost-intensive and time-consuming and are often insufficient to predict human relevant cardiotoxicity. The purpose of this study was to develop an in vitro repeated exposure toxicity methodology allowing the identification of predictive genomics biomarkers of functional relevance for drug-induced cardiotoxicity in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). The hiPSC-CMs were incubated with 156 nM doxorubicin, which is a well-characterized cardiotoxicant, for 2 or 6 days followed by washout of the test compound and further incubation in compound-free culture medium until day 14 after the onset of exposure. An xCELLigence Real-Time Cell Analyser was used to monitor doxorubicin-induced cytotoxicity while also monitoring functional alterations of cardiomyocytes by counting of the beating frequency of cardiomyocytes. Unlike single exposure, repeated doxorubicin exposure resulted in long-term arrhythmic beating in hiPSC-CMs accompanied by significant cytotoxicity. Global gene expression changes were studied using microarrays and bioinformatics tools. Analysis of the transcriptomic data revealed early expression signatures of genes involved in formation of sarcomeric structures, regulation of ion homeostasis and induction of apoptosis. Eighty-four significantly deregulated genes related to cardiac functions, stress and apoptosis were validated using real-time PCR. The expression of the 84 genes was further studied by real-time PCR in hiPSC-CMs incubated with daunorubicin and mitoxantrone, further anthracycline family members that are also known to induce cardiotoxicity. A panel of 35 genes was deregulated by all three anthracycline family members and can therefore be expected to predict the cardiotoxicity of compounds acting by similar mechanisms as doxorubicin, daunorubicin or mitoxantrone. The identified gene panel can be applied in the safety assessment of novel drug candidates as well as available therapeutics to identify compounds that may cause cardiotoxicity.

Interactions Between Nutraceutical Supplements and Standard Acute Myeloid Leukemia Chemotherapeutics.

PURPOSE: Concomitant use of nutraceuticals with chemotherapy is very common. Cancer patients self-medicate to relieve the side effects associated with chemotherapy, improve disease outcome and to regain control of their medical care. However, there is limited empirical evidence on potential drug-nutraceutical interactions and their resulting effect on chemotherapy efficacy. METHOD: To investigate drug-nutraceutical interactions we created and screened a library of commonly used nutraceuticals for their modulatory effects on the activity of cytarabine and daunorubicin, two primary chemotherapeutics used to treat acute myeloid leukemia (AML). Combination screening was performed in 3 AML cell lines (OCI-AML2, KG1a and U937) using the MTS viability assay. Lead compounds were validated using with the Annexin V/ Propidium iodide assay and CalcuSyn drug combination software. RESULTS: We identified zinc as a nutraceutical that enhanced AML chemotherapy efficacy with combination index (CI) values of 0.649, 0.632 and 0.615 at EC 25, 50 and 75, respectively; CI values <0.9, >1.1 or between 0.9-1.1 denote statistical synergy, antagonism or additivity, respectively. In contrast, we show that echinacea hindered AML chemotherapy efficacy by significantly reducing the ability of cytarabine to induce cell death. CONCLUSION: Given the positive and negative effects of nutraceuticals, patients undergoing chemotherapy must consult with their oncologist before consuming over-the-counter supplements. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Addition of sorafenib versus placebo to standard therapy in patients aged 60 years or younger with newly diagnosed acute myeloid leukaemia (SORAML): a multicentre, phase 2, randomised controlled trial.

BACKGROUND: Preclinical data and results from non-randomised trials suggest that the multikinase inhibitor sorafenib might be an effective drug for the treatment of acute myeloid leukaemia. We investigated the efficacy and tolerability of sorafenib versus placebo in addition to standard chemotherapy in patients with acute myeloid leukaemia aged 60 years or younger. METHODS: This randomised, double-blind, placebo-controlled, phase 2 trial was done at 25 sites in Germany. We enrolled patients aged 18-60 years with newly diagnosed, previously untreated acute myeloid leukaemia who had a WHO clinical performance score 0-2, adequate renal and liver function, no cardiac comorbidities, and no recent trauma or operation. Patients were randomly assigned (1:1) to receive two cycles of induction therapy with daunorubicin (60 mg/m(2) on days 3-5) plus cytarabine (100 mg/m(2) on days 1-7), followed by three cycles of high-dose cytarabine consolidation therapy (3 g/m(2) twice daily on days 1, 3, and 5) plus either sorafenib (400 mg twice daily) or placebo on days 10-19 of induction cycles 1 and 2, from day 8 of each consolidation, and as maintenance for 12 months. Allogeneic stem-cell transplantation was scheduled for all intermediate-risk patients with a sibling donor and for all high-risk patients with a matched donor in first remission. Computer-generated randomisation was done in blocks. The primary endpoint was event-free survival, with an event defined as either primary treatment failure or relapse or death, assessed in all randomised patients who received at least one dose of study treatment. We report the final analysis. This trial is registered with ClinicalTrials.gov, number NCT00893373, and the EU Clinical Trials Register (2008-004968-40). FINDINGS: Between March 27, 2009, and Nov 28, 2011, 276 patients were enrolled and randomised, of whom nine did not receive study medication. 267 patients were included in the primary analysis (placebo, n=133; sorafenib, n=134). With a median follow-up of 36 months (IQR 35·5-38·1), median event-free survival was 9 months (95% CI 4-15) in the placebo group versus 21 months (9-32) in the sorafenib group, corresponding to a 3-year event-free survival of 22% (95% CI 13-32) in the placebo group versus 40% (29-51) in the sorafenib group (hazard ratio [HR] 0·64, 95% CI; 0·45-0·91; p=0·013). The most common grade 3-4 adverse events in both groups were fever (71 [53%] in the placebo group vs 73 [54%] in the sorafenib group), infections (55 [41%] vs 46 [34%]), pneumonia (21 [16%] vs 20 [14%]), and pain (13 [10%] vs 15 [11%]). Grade 3 or worse adverse events that were significantly more common in the sorafenib group than the placebo group were fever (relative risk [RR] 1·54, 95% CI 1·04-2·28), diarrhoea (RR 7·89, 2·94-25·2), bleeding (RR 3·75, 1·5-10·0), cardiac events (RR 3·46, 1·15-11·8), hand-foot-skin reaction (only in sorafenib group), and rash (RR 4·06, 1·25-15·7). INTERPRETATION: In patients with acute myeloid leukaemia aged 60 years or younger, the addition of sorafenib to standard chemotherapy has antileukaemic efficacy but also increased toxicity. Our findings suggest that kinase inhibitors could be a useful addition to curative treatment for acute myeloid leukaemia. Overall survival after long-term follow-up and strategies to reduce toxicity are needed to determine the future role of sorafenib in treatment of this disease. FUNDING: Bayer HealthCare.

The modulation of carbonyl reductase 1 by polyphenols.

Carbonyl reductase 1 (CBR1), an enzyme belonging to the short-chain dehydrogenases/reductases family, has been detected in all human tissues. CBR1 catalyzes the reduction of many xenobiotics, including important drugs (e.g. anthracyclines, nabumetone, bupropion, dolasetron) and harmful carbonyls and quinones. Moreover, it participates in the metabolism of a number of endogenous compounds and it may play a role in certain pathologies. Plant polyphenols are not only present in many human food sources, but are also a component of many popular dietary supplements and herbal medicines. Many studies reviewed herein have demonstrated the potency of certain flavonoids, stilbenes and curcuminoids in the inhibition of the activity of CBR1. Interactions of these polyphenols with transcriptional factors, which regulate CBR1 expression, have also been reported in several studies. As CBR1 plays an important role in drug metabolism as well as in the protection of the organism against potentially harmful carbonyls, the modulation of its expression/activity may have significant pharmacological and/or toxicological consequences. Some polyphenols (e.g. luteolin, apigenin and curcumin) have been shown to be very potent CBR1 inhibitors. The inhibition of CBR1 seems useful regarding the increased efficacy of anthracycline therapy, but it may cause the worse detoxification of reactive carbonyls. Nevertheless, all known information about the interactions of polyphenols with CBR1 have only been based on the results of in vitro studies. With respect to the high importance of CBR1 and the frequent consumption of polyphenols, in vivo studies would be very helpful for the evaluation of risks/benefits of polyphenol interactions with CBR1.

Tripterygium wilfordii Hook F extract in cART-treated HIV patients with poor immune response: a pilot study to assess its immunomodulatory effects and safety.

BACKGROUND: Despite combination antiretroviral therapy (cART), 20% of HIV-infected patients are unable to achieve adequate immunologic recovery, in which immune activation plays a crucial role. We hypothesize that extract of Tripterygium wilfordii Hook F (TwHF), a Chinese medication used to treat autoimmune diseases, has immunomodulatory effects that may help CD4 cell recovery. METHODS: Eighteen cART-treated HIV-infected patients virally suppressed for over 12 months with suboptimal CD4 cell recovery were enrolled. TwHF extract was administered at a dosage of 10 mg three times daily for 12 months. T-cell subsets and activation markers were evaluated at baseline and during follow-up. The trial was registered at Clinicaltrials.gov (NCT02002286). RESULTS: TwHF extract was associated with a mean increase in CD4 cell count of 88 cells/µl (95% confidential interval [CI], 72-105 cells/µl) after one year of treatment. A significant increase in the mean rate of CD4 cell recovery (26 before vs 75 cells/µl/year after TwHF use, P < 0.001) was observed. Analysis of 13 patients with activation profiles suggested that TwHF extract was associated with a decrease in T-cell immune activation which was temporally correlated with CD4 cell recovery. No discontinuation of TwHF extract was reported. CONCLUSION: Use of TwHF extract in HIV-infected patients was associated with a reduction in T-cell activation and improved CD4 recovery with an excellent safety profile.

A Novel Approach of Daunorubicin Application on Formation of Proliferative Retinopathy Using a Porous Silicon Controlled Delivery System: Pharmacodynamics.

PURPOSE: Proliferative vitreoretinopathy (PVR) is the most common cause of poor visual outcomes in association with retinal detachment surgeries and ocular trauma. Daunorubicin (DNR) has shown the strongest efficacy in proliferation inhibition in vitro. However, clinical studies have shown only mild effect owing to limitations of narrow therapeutic window and short vitreous half-life. METHODS: Three milligrams of DNR-loaded particles were intravitreally injected into 18 pigmented rabbits, and vitreous samples were collected up to 84 days for analysis. Thirty-seven rabbits were used for a dose-escalation (1, 3, 6 mg) safety and efficacy study in a rabbit PVR model using a pretreatment design. RESULTS: Loading efficiency of DNR was 108.55 ± 12 µg per 1 mg particles. Eighty-four days of follow-up did not reveal any adverse reaction. Pharmacokinetic analysis demonstrated a vitreous half-life of 29 days with a maximum DNR concentration of 178 ng/mL and a minimum concentration of 29 ng/mL at day 84. Daunorubicin-loaded porous silicon (pSi) particles were dosed 8 to 9 weeks before PVR induction, and PVR severity score was dose dependent (Spearman ρ = -0.25, P = 0.0005). Proliferative vitreoretinopathy with tractional retinal detachment was 88% in the control group, 63% in the low-dose group, 14% in the medium-dose group, and 0% in the high-dose group (Cochran-Armitage Trend Test, Z = 8.99, ρ = -0.67, P < 0.0001). CONCLUSIONS: Daunorubicin-loaded pSi particles can safely reside in the vitreous for at least 3 months. The pSi-based delivery expanded the therapeutic window of DNR by a factor of 862 and drove down the minimum effective concentration by a factor of 175.

Characterization of the Canine Anthracycline-Metabolizing Enzyme Carbonyl Reductase 1 (cbr1) and the Functional Isoform cbr1 V218.

The anthracyclines doxorubicin and daunorubicin are used in the treatment of various human and canine cancers, but anthracycline-related cardiotoxicity limits their clinical utility. The formation of anthracycline C-13 alcohol metabolites (e.g., doxorubicinol and daunorubicinol) contributes to the development of anthracycline-related cardiotoxicity. The enzymes responsible for the synthesis of anthracycline C-13 alcohol metabolites in canines remain to be elucidated. We hypothesized that canine carbonyl reductase 1 (cbr1), the homolog of the prominent anthracycline reductase human CBR1, would have anthracycline reductase activity. Recombinant canine cbr1 (molecular weight: 32.8 kDa) was purified from Escherichia coli. The enzyme kinetics of "wild-type" canine cbr1 (cbr1 D218) and a variant isoform (cbr1 V218) were characterized with the substrates daunorubicin and menadione, as well as the flavonoid inhibitor rutin. Canine cbr1 catalyzes the reduction of daunorubicin to daunorubicinol, with cbr1 D218 and cbr1 V218 displaying different kinetic parameters (cbr1 D218 Km: 188 ± 144 µM versus cbr1 V218 Km: 527 ± 136 µM, P < 0.05, and cbr1 D218 Vmax: 6446 ± 3615 nmol/min per milligram versus cbr1 V218 Vmax: 15539 ± 2623 nmol/min per milligram, P < 0.01). Canine cbr1 also metabolized menadione (cbr1 D218 Km: 104 ± 50 µM, Vmax: 2034 ± 307 nmol/min per milligram). Rutin acted as a competitive inhibitor for the reduction of daunorubicin (cbr1 D218 Ki: 1.84 ± 1.02 µM, cbr1 V218 Ki: 1.38 ± 0.47 µM). These studies show that canine cbr1 metabolizes daunorubicin and provide the necessary foundation to characterize the role of cbr1 in the variable pharmacodynamics of anthracyclines in canine cancer patients.