Effect of senolytic drugs in young female mice chemically induced to estropause.

AIMS: This study aimed to assess metabolic responses and senescent cell burden in young female mice induced to estropause and treated with senolytic drugs. MAIN METHODS: Estropause was induced by 4-vinylcyclohexene diepoxide (VCD) injection in two-month-old mice. The senolytics dasatinib and quercetin (D + Q) or fisetin were given by oral gavage once a month from five to 11 months of age. KEY FINDINGS: VCD-induced estropause led to increased body mass and reduced albumin concentrations compared to untreated cyclic mice, without affecting insulin sensitivity, lipid profile, liver enzymes, or total proteins. Estropause decreased catalase activity in adipose tissue but had no significant effect on other redox parameters in adipose and hepatic tissues. Fisetin treatment reduced ROS levels in the hepatic tissue of estropause mice. Estropause did not influence senescence-associated beta-galactosidase activity in adipose and hepatic tissues but increased senescent cell markers and fibrosis in ovaries. Senolytic treatment did not decrease ovarian cellular senescence induced by estropause. SIGNIFICANCE: Overall, the findings suggest that estropause leads to minor metabolic changes in young females, and the senolytics D + Q and fisetin had no protective effects despite increased ovarian senescence.

Quercetin and dasatinib, two powerful senolytics in age-related cardiovascular disease.

Cellular senescence is characteristic of the development and progression of multiple age-associated diseases. Accumulation of senescent cells in the heart contributes to various age-related pathologies. Several compounds called senolytics have been designed to eliminate these cells within the tissues. In recent years, the use and study of senolytics increased, representing a promising field for finding accessible and safe therapies for cardiovascular disease (CVD) treatment. This mini-review discusses the changes in the aging heart and the participation of senescent cells in CVD, as well as the use of senolytics to prevent the progression of myocardial damage, mainly the effect of dasatinib and quercetin. In particular, the mechanisms and physiological effects of senolytics therapies in the aged heart are discussed.

Dasatinib and quercetin increase testosterone and sperm concentration in mice.

Cellular senescence is a defense mechanism to arrest proliferation of damaged cells. The number of senescent cells increases with age in different tissues and contributes to the development of age-related diseases. Old mice treated with senolytics drugs, dasatinib and quercetin (D+Q), have reduced senescent cells burden. The aim of this study was to evaluate the effects of D+Q on testicular function and fertility of male mice. Mice (n = 9/group) received D (5 mg kg-1) and Q (50 mg kg-1) via gavage every moth for three consecutive days from 3 to 8 months of age. At 8 months mice were breed with young non-treated females and euthanized. The treatment of male mice with D+Q increased serum testosterone levels and sperm concentration and decreased abnormal sperm morphology. Sperm motility, seminiferous tubule morphometry, testicular gene expression and fertility were not affected by treatment. There was no effect of D+Q treatment in ß-galactosidase activity and in lipofuscin staining in testes. D+Q treatment also did not affect body mass gain and testes mass. In conclusion, D+Q treatment increased serum testosterone levels and sperm concentration and decreased abnormal sperm morphology, however did not affect fertility. Further studies with older mice and different senolytics are necessary to elucidate the effects in the decline of sperm output (quality and quantity) associated with aging.

Identification of inhibitors for the transmembrane Trypanosoma cruzi eIF2α kinase relevant for parasite proliferation.

The TcK2 protein kinase of Trypanosoma cruzi, the causative agent of Chagas disease, is structurally similar to the human kinase PERK, which phosphorylates the initiation factor eIF2α and, in turn, inhibits translation initiation. We have previously shown that absence of TcK2 kinase impairs parasite proliferation within mammalian cells, positioning it as a potential target for treatment of Chagas disease. To better understand its role in the parasite, here we initially confirmed the importance of TcK2 in parasite proliferation by generating CRISPR/Cas9 TcK2-null cells, albeit they more efficiently differentiate into infective forms. Proteomics indicates that the TcK2 knockout of proliferative forms expresses proteins including trans-sialidases, normally restricted to infective and nonproliferative trypomastigotes explaining decreased proliferation and better differentiation. TcK2 knockout cells lost phosphorylation of eukaryotic initiation factor 3 and cyclic AMP responsive-like element, recognized to promote growth, likely explaining both decreased proliferation and augmented differentiation. To identify specific inhibitors, a library of 379 kinase inhibitors was screened by differential scanning fluorimetry using a recombinant TcK2 encompassing the kinase domain and selected molecules were tested for kinase inhibition. Only Dasatinib and PF-477736, inhibitors of Src/Abl and ChK1 kinases, showed inhibitory activity with IC50 of 0.2 ± 0.02 mM and 0.8 ± 0.1, respectively. In infected cells Dasatinib inhibited growth of parental amastigotes (IC50 = 0.6 ± 0.2 mM) but not TcK2 of depleted parasites (IC50 > 34 mM) identifying Dasatinib as a potential lead for development of therapeutics for Chagas disease targeting TcK2.

Natural Products as a Major Source of Candidates for Potential Senolytic Compounds obtained by in silico Screening.

BACKGROUND: Preclinical studies suggest that senolytic compounds such as quercetin (a natural product) and dasatinib (a synthetic product) decrease senescent cells, reduce inflammation, and alleviate human frailty. This evidence has opened a new field of research for studying the effect of these compounds on age-related dysfunction and diseases. OBJECTIVE: The present study performed in silico and we identified new potential senolytic candidates from an extensive database that contains natural products (NPs) and semi-synthetic products (SMSs). METHODS: Computer programs Chemminer and rcdk packages, which compared the fingerprints of numerous molecules (40,383) with reference senolytics, and the creation of a pharmacological network built with signaling pathways and targets involved in senescence processes were used to identify compounds with a potential activity. RESULTS: Six drug-like candidates (3,4'-dihydroxypropiophenone, baicalein, α, ß-dehydrocurvularin, lovastatin, luteolin, and phloretin) were identified. CONCLUSION: To our knowledge, this is the first time that these six natural molecules have been proposed to have senolytic activity. To validate the methodology employed in the identification of new drug-like senolytics, experimental evidence is needed with models that evaluate senolytic activity.

Development and validation of liquid chromatography-tandem mass spectrometry method to quantify dasatinib in plasma and its application to a pharmacokinetic study

Abstract Dasatinib, a potent oral multi-targeted kinase inhibitor against Src and Bcr-Abl, can decrease inflammatory response in sepsis. A simple and cost-effective method for determination of an effective dose dasatinib was established. This method was validated in human plasma, with the aim of reducing the number of animals used, thus, avoiding ethical problems. Dasatinib and internal standard lopinavir were extracted from 180 uL of plasma using liquid-liquid extraction with methyl tert-butil ether, followed by liquid chromatography coupled to triple quadrupole mass spectrometry in multiple reaction monitoring mode. For the pharmacokinetic study, 1 mg/kg of dasatinib was administered to mice with and without sepsis. The method was linear over the concentration range of 1-98 ng/mL for DAS in mice and human plasma, with r2>0.99 and presented intra- and interday precision within the range of 2.3 - 6.2 and 4.3 - 7.0%, respectively. Further intra- and interday accuracy was within the range of 88.2 - 105.8 and 90.6 - 101.7%, respectively. The mice with sepsis showed AUC0-t = 2076.06 h*ng/mL and Cmax =102.73 ng/mL and mice without sepsis presented AUC0-t = 2128.46 h*ng/mL. Cmax = 164.5 ng/mL. The described analytical method was successfully employed in pharmacokinetic study of DAS in mice.

Senolytic treatment reverses obesity-mediated senescent cell accumulation in the ovary.

Senescent cells are in a cell cycle arrest state and accumulate with aging and obesity, contributing to a chronic inflammatory state. Treatment with senolytic drugs dasatinib and quercetin (D + Q) can reduce senescent cell burden in several tissues, increasing lifespan. Despite this, there are few reports about senescent cells accumulating in female reproductive tissues. Therefore, the aim of the study was to characterize the ovarian reserve and its relationship with cellular senescence in genetically obese mice (ob/ob). In experiment 1, ob/ob (n = 5) and wild-type (WT) mice (n = 5) at 12 months of age were evaluated. In experiment 2, 2-month-old female ob/ob mice were treated with senolytics (D + Q, n = 6) or placebo (n = 6) during the 4 months. Obese mice had more senescent cells in ovaries, indicated by increased p21 and p16 and lipofuscin staining and macrophage infiltration. Treatment with D + Q significantly reduced senescent cell burden in ovaries of obese mice. Neither obesity nor treatment with D + Q affected the number of ovarian follicles. In conclusion, our data indicate that obesity due to leptin deficiency increases the load of senescent cells in the ovary, which is reduced by treatment by senolytics. However, neither obesity nor D + Q treatment affected the ovarian reserve.

Eficacia y seguridad del Nilotinib como tratamiento de segunda línea en pacientes con Leucemia Mieloide Crónica, sin mutación T315I, con resistencia o intolerancia a Imatinib o Dasatinib / Eficacia y seguridad del Nilotinib como tratamiento de segunda línea en pacientes con Leucemia Mieloide Crónica, sin mutación T315I, con resistencia o intolerancia a Imatinib o Dasatinib

INTRODUCCIÓN: La incidencia de pacientes con leucemia mieloide crónica llega a representar el 15%- 20% de las leucemias, de las cuales la mayoría inicia un tratamiento de primera línea (imatinib o dasatinib). Sin embargo, un porcentaje de ellos generan intolerancia o resistencia, teniendo que iniciar TKI de nueva generación. Actualmente a nivel institucional se cuenta con 07 pacientes con leucemia mieloide crónica en fase crónica que reciben tratamiento con nilotinib. El nilotinib es un inhibidor de la actividad de la tirosina quinasa ABL de la oncoproteína BCR-ABL. Actúa en las líneas celulares como en las células leucémicas primarias "cromosoma Filadelfia positivo". Se utiliza en el tratamiento de pacientes adultos con leucemia mieloide crónica (LMC) cromosoma Filadelfia positivo en fase crónica y en fase acelerada, con intolerancia a un tratamiento previo. METODOLOGÍA: Se realizó una búsqueda sistemática y dirigida de las principales bases de datos encontrándose 02 ETS, 05 GPC y 01 RS y 02 estudios primarios sobre el tema. Las 05 GPC encontradas incluyen el uso de un TKi de segunda generación como parte de una segunda línea de tratamiento en pacientes LMC-FC que sean resistentes a imatinib en primera línea, éstas GPC revisadas también mencionan que el uso de nilotinib debe plantearse en casos específicos donde los pacientes hayan recibido una terapia de primera línea con imatinib a la cual sean intolerantes o resistentes y que de manera individual podrían tener factores de riesgo para que sean más propensos a desarrollar eventos adversos o intolerancia/resistencia a dasatinib. RESULTADOS: Las 02 ETS encontradas avalan el uso de nilotinib en pacientes con LMC-FC que reporten intolerancia o resistencia a imatinib o dasatinib, de estas ETS corresponden a una realizada a nivel nacional y otra realizada en un país latinoamericano con contextos similares a Perú. La RS y los estudios primarios reportados han concluido que nilotinib ha presentado desenlaces favorables y EA infrecuentes en el manejo de la LMC-FC. Sin embargo, los estudios incluidos en la RS y los estudios primarios eran de un solo brazo. Ello establece ciertas limitaciones en la evidencia encontrada. CONCLUSIÓN: Si bien la mejor evidencia científica disponible es limitada; sin embargo, se ha reportado tanto en las ETS, GPC, RS y en los estudios primarios recomendaciones a favor, desenlaces favorables y eventos adversos manejables de nilotinib en terapia de segunda línea. Por lo cual, el panel aprueba el uso de nilotinib en pacientes con LMC-FC que sean resistentes o intolerantes a imatinib en primera línea.

Eficacia y seguridad de dasatinib en pacientes adultos con leucemia linfoblástica aguda philadelphia positivo resistente o intolerante a quimioterapia más imatinib / Efficacy and safety of dasatinib in adult patients with philadelphia-positive acute lymphoblastic leukemia resistant or intolerant to chemotherapy plus imatinib

ANTECEDENTES : El presente dictamen expone la evaluación de la eficacia y seguridad de dasatinib con o sin quimioterapia, comparado con quimioterapia, en pacientes adultos con leucemia linfoblástica aguda, philadelphia positivo, resistente o intolerante a quimioterapia más imatinib. En la literatura se señala que, la leucemia linfoblástica aguda (LLA) cromosoma Philadelphia positivo (Ph+) representa entre el 20.0 al 30 % de los casos de LLA. En el Perú, no se conoce el número de casos de LLA Ph+; sin embargo, se conoce que, en el 2019, la tasa de incidencia de LLA en personas mayores de 20 años fue de 1.04 casos por cada 100,000 personas y la tasa de mortalidad fue de 0.79 muertes por cada 100,000 personas.  Luego de la terapia de inducción con un inhibidor de la tirosina quinasa (TKI, por sus siglas en inglés), entre el 10 y 20 % de los pacientes desarrolla LLA resistente. Debido a la aparición de casos de resistencia o intolerancia a los TKI de primera generación (imatinib), se han desarrollado otros TKI, como dasatinib. En EsSalud, se cuentan con varias opciones de medicamentos que pueden ser empleados en diferentes esquemas de quimioterapia en este grupo de pacientes con resistencia o intolerancia a TKI. Actualmente, dasatinib se encuentra disponible en EsSalud para el tratamiento de pacientes con leucemia mieloide crónica (LMC), Ph+ resistente o intolerante a tratamientos previos a dosis altas a imatinib y sin mutación T315l. No obstante, algunos especialistas de EsSalud solicitan que se amplíe el uso de dasatinib a pacientes adultos con LLA Ph+ resistente o intolerante, aduciendo que dasatinib (con o sin quimioterapia) podría mejorar la sobrevida libre de progresión (SLP) del paciente. Así, el presente dictamen preliminar expone la evaluación de la eficacia y seguridad de dasatinib, con o sin quimioterapia, en pacientes adultos con LLA Ph+ resistente o intolerante a quimioterapia más imatinib. METODOLOGÍA: Tras la búsqueda de la literatura científica, se identificaron dos guías de práctica clínicas (GPC) elaboradas por The National Comprehensive Cancer Network (NCCN) y The European Society for Medical Oncology (ESMO), y dos evaluaciones de tecnologías sanitarias (ETS) elaboradas por The Scottish Medicines Consortium (SMC) y Comissão Nacional de Incorporação de Tecnologías no Sistema Único de Saúde (CONITEC). Además, se encontraron dos estudios de fase II; sin grupo de comparación, el estudio START-L (Ottman et al., 2007), empleado para sustentar la aprobación acelerada de uso de dasatinib por parte de la Food and Drug Administration (FDA) y la aprobación de la European Medicines Agency (EMA) en pacientes con LLA Ph+ y resistencia o intolerancia a una terapia previa, y el estudio de Sakamaki et al., 2009. RESULTADOS: Se describe la evidencia disponible según el tipo de publicación, siguiendo lo indicado en los criterios de elegibilidad. CONCLUSIONES: En el presente documento, se evaluó la mejor evidencia científica disponible hasta la actualidad, sobre la eficacia y seguridad de dasatinib con o sin quimioterapia, comparado con quimioterapia, en pacientes adultos con LLA Ph+y resistencia o intolerancia a la quimioterapia más imatinib. La búsqueda sistemática de la evidencia culminó con la selección de dos GPC (NCCN 2021; Hoelzer et al. 2016), dos ETS (CONITEC 2020; SMC 2007), el estudio de fase II START-L, pivotal de dasatinib (Ottmann et al. 2007), y el estudio de fase II de Sakamaki et al. (Sakamaki et al. 2009). Las GPC del NCCN y ESMO coinciden en señalar que la evidencia disponible sobre el uso de dasatinib para el tratamiento de los pacientes con LLA Ph+ y resistencia o recaída no es de calidad. Por ello, la ESMO resalta que no hay una terapia estándar de reinducción y el NCCN recomienda, especialmente, la participación en un ensayo clínico. Las ETS del SMC y del CONITEC coinciden en dar una recomendación en contra del uso de dasatinib en pacientes con LLA Ph+ con resistencia/recaída a una terapia previa o al mesilato de imatinib. La SMC basó en que la terapia con dasatinib no sería costo-efectiva en este grupo de pacientes; y la CONITEC, en la alta incidencia de EAS, y las altas tasas de abandono del tratamiento y de reducción de dosis observadas en la evidencia analizada. Los estudios START-L y de Sakamaki et al., de fase II, presentaron limitaciones (e.g. falta de un grupo de comparación, pequeño tamaño de la muestra y la falta de acceso al protocolo del estudio) que afectan la validez de sus resultados. Aun así, sus resultados sugieren que el perfil de seguridad de dasatinib no puede ser considerado como favorable para los pacientes (altas tasas de eventos adversos, reducción de dosis de dasatinib y descontinuación del tratamiento). Actualmente, en EsSalud, se cuentan con varias opciones de medicamentos que pueden ser empleados en diferentes esquemas de quimioterapia para pacientes con LLA Ph+ resistente o intolerante a quimioterapia más imatinib. Por lo expuesto, el IETSI no aprueba el uso de dasatinib con o sin quimioterapia en pacientes adultos con LLA Ph+ resistente o intolerante a quimioterapia más imatinib.

Investigation on the interaction behavior of afatinib, dasatinib, and imatinib docked to the BCR-ABL protein.

Chronic myeloid leukemia (CML) is a pathological condition associated with the uncontrolled proliferation of white blood cells and respective loss of function. Imatinib was the first drug that could effectively treat this condition, but its use is hindered by the development of mutations of the BCR-ABL protein, which are the cause of resistance. Therefore, dasatinib and afatinib present similarities that can be explored to discover new molecules capable of overcoming the effects of imatinib. Afatinib exhibited electronic and docking behavior, indicating that a replacement with some minor modifications could design a new potential inhibitor. The amide group in each candidate is clearly of pharmacophoric importance, and it needs to concentrate a negative region. Sulfur group presents a good pharmacophoric profile, which was shown by dasatinib results, adding to the influence of the Met318 residue in the target protein active site configuration. This behavior suggests that the sulfur atom and other fragments that have an affinity for the methionine sidechain may provide a significant positive effect when present in TKI molecules such as afatinib or dasatinib.

Eficacia y seguridad de bosutinib en pacientes con leucemia mieloide crónica con el gen de fusion bcr-abl, con mutación T315I negativo y con falla y/o intolerancia a imatinib, dasatinib y nilotinib / Efficacy and safety of bosutinib in patients with chronic myeloid leukemia with the bcr-abl fusion gene, negative T315I mutation and with failure and/or intolerance to imatinib, dasatinib and nilotinib

INTRODUCCIÓN: El presente dictamen preliminar expone la evaluación de la eficacia y seguridad de bosutinib, comparado con la mejor terapia de soporte, para el tratamiento de pacientes con leucemia mieloide crónica con el gen de fusión BCR-ABL, con mutación T315I negativo y con falla y/o intolerancia a imatinib, dasatinib y nilotinib. La leucemia mieloide crónica (LMC) es una neoplasia mieloproliferativa y de baja frecuencia; no obstante, es la sexta causa de muerte por cáncer en Perú. El gen de fusión BCR-ABL, presente en más del 90 % de los casos, produce una proteína con alta actividad catalítica de tirosina quinasa, implicada en la patogénesis de la LMC. Esta enfermedad consta de tres fases: crónica, acelerada y de crisis blástica. Si bien el trasplante alogénico de células hematopoyéticas (TACMH) es potencialmente curativo, algunos pacientes no son candidatos a recibir un TACMH o no es posible encontrar un donante compatible. En estos casos, los pacientes pueden recibir inhibidores de la tirosina quinasa (ITQ), los cuales actúan de manera específica sobre la proliferación celular inducida por el gen de fusión BCR-ABL. En EsSalud se cuenta con tres ITQ (imatinib, dasatinib y nilotinib) que pueden ser utilizados hasta una tercera línea de tratamiento. Sin embargo, existen pacientes, con la mutación T315I negativo, no respondedores a los tres ITQ por falla o intolerancia, para quienes los médicos especialistas de la institución sugieren el uso de bosutinib, un ITQ de segunda generación, como cuarta línea de tratamiento. METODOLOGÍA: Se llevó a cabo una búsqueda sistemática de la literatura con el objetivo de identificar la mejor evidencia sobre la eficacia y seguridad de bosutinib, en comparación con la mejor terapia de soporte, para el tratamiento de pacientes con LMC con el gen de fusión BCR-ABL, con mutación T315I negativo y con falla y/o intolerancia a imatinib, dasatinib y nilotinib. La búsqueda se realizó en las bases de datos: PubMed, The Cochrane Library y LILACS. Adicionalmente, se realizó una búsqueda manual dentro de las páginas web pertenecientes a grupos que realizan evaluación de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC) incluyendo: el National Institute for Health and Care Excellence (NICE), la Canadian Agency for Drugs and Technologies in Health (CADTH), el Scottish Medicines Consortium (SMC), el Scottish Intercollegiate Guidelines Network (SIGN), el Institute for Clinical and Economic Review (ICER), el Institute for Quality and Efficiency in Healthcare (IQWiG por sus siglas en alemán), la Base Regional de Informes de Evaluación de Tecnologías en Salud de las Américas (BRISA), la OMS, el Ministerio de Salud del Perú (MINSA), el Instituto de Evaluación de Tecnologías en Salud e Investigación (IETSI), la National Comprehensive Cancer Network (NCCN), la British Society for Haematology (BSH) y la European Society for Medical Oncology (ESMO). Finalmente, se realizó una búsqueda manual en la página web de registro de ensayos clínicos (EC) de ClinicalTrials.gov para identificar EC en curso o con resultados que no hayan sido publicados. RESULTADOS: La presente sinopsis describe la evidencia científica sobre el uso de bosutinib como tratamiento de pacientes con LMC con el gen de fusión BCR-ABL, con mutación T315I negativo y con falla y/o intolerancia a imatinib, dasatinib y nilotinib, según el tipo de publicación. CONCLUSIONES: El objetivo del presente dictamen fue evaluar la mejor evidencia disponible sobre la eficacia y seguridad de bosutinib comparado con la mejor terapia de soporte (hidroxiurea) para el tratamiento de pacientes con LMC con el gen de fusión BCR-ABL (cromosoma Ph positivo), con mutación T315I negativo y con falla y/o intolerancia a imatinib, dasatinib y nilotinib. La población de interés (pacientes con LMC con cromosoma Ph positivo, con mutación T315I negativo y con falla y/o intolerancia imatinib, dasatinib y nilotinib) no cuenta con una alternativa de tratamiento contra la LMC (vacío terapéutico), ante el vacío terapéutico estos pacientes progresarían a etapas más avanzadas con mayor riesgo de muerte. Luego de la búsqueda de la literatura se identificó una GPC desarrollada por BSH; cuatro ETS desarrolladas por el SMC, la CADTH, el NICE y el IQWiG; un EC de fase I/II (estudio pivotal) publicado por Khoury et al.; un EC de fase IV (fase de post comercialización) publicado por Hochhaus et al. y un estudio observacional retrospectivo publicado por García-Gutiérrez et al. Debido a las limitaciones del los ECA de fase II y IV y el estudio observacional (todos sin grupo de comparación), la eficacia y seguridad de bosutinib y su beneficio neto en la calidad de vida son inciertos puesto que no se puede establecer una relación causal entre los resultados reportados y el tratamiento con bosutinib. No obstante, cabe precisar que datos descriptivos muestran que la mortalidad a los dos años con el uso bosutinib es menor al 5 %, mientras que con el uso de hidroxiurea sería entre 20 % y 47.5 %. La guía recomienda usar ITQ en el contexto de cuarta línea en pacientes con intolerancia a ITQ recibidos previamente. No obstante, no se especifica la evidencia de soporte. Las ETS de NICE, SMC y CADTH optaron por recomendar el uso de bosutinib en pacientes adultos con LMC con cromosoma Ph positivo, que previamente han recibido ITQ y para quienes imatinib, dasatinib y nilotinib no son apropiados, dicha recomendación fue condicionada a un descuento confidencial sobre el precio de lista de bosutinib. Las tres ETS emplearon como evidencia de soporte el estudio clínico fase I/II, el cual incluyó solo tres pacientes que recibieron bosutinib en cuarta línea. La ETS de IQWiG concluye que no es posible determinar el beneficio del tratamiento con bosutinib frente a otro ITQ. La principal limitación para ello fue que el EC de fase I/II no evalúa bosutinib frente a los comparadores de interés para IQWiG, los cuales fueron diferentes a los establecidos en la PICO del presente dictamen. El uso prolongado de la terapia de soporte con hidroxiurea podría generar similares incidencias de EA que con bosutinib (toxicidad gastrointestinal, neutropenia, anemia, trombocitopenia); pero, adicionalmente podría generar otros problemas como ulceras graves, neoplasias malignas, toxicidad pulmonar, mielosupresión grave, entre otros. Existe plausibilidad biológica; ya que no todas las mutaciones que confieren resistencia a imatinib, dasatinib o nilotinib, confieren resistencia a bosutinib; y aún existe la posibilidad de que bosutinib sí sea eficaz. Por lo expuesto, el Instituto de Evaluación de Tecnologías en Salud e Investigación aprueba el uso de bosutinib para el tratamiento de pacientes con LMC con el gen de fusión BCR-ABL (cromosoma Ph positivo), con mutación T315I negativo, con falla y/o intolerancia a tres inhibidores de la tirosina quinasa (imatinib, dasatinib y nilotinib), según lo establecido en el Anexo N°1. La vigencia del presente dictamen preliminar es de un año a partir de la fecha de publicación. Así, la continuación de dicha aprobación estará sujeta a la evaluación de los resultados obtenidos y de mayor evidencia que pueda surgir en el tiempo.

Senolytic Combination of Dasatinib and Quercetin Alleviates Intestinal Senescence and Inflammation and Modulates the Gut Microbiome in Aged Mice.

Cellular senescence contributes to age-related disorders including physical dysfunction, disabilities, and mortality caused by tissue inflammation and damage. Senescent cells accumulate in multiple tissues with aging and at etiological sites of multiple chronic disorders. The senolytic drug combination, Dasatinib plus Quercetin (D+Q), is known to reduce senescent cell abundance in aged mice. However, the effects of long-term D+Q treatment on intestinal senescent cell and inflammatory burden and microbiome composition in aged mice remain unknown. Here, we examine the effect of D+Q on senescence (p16Ink4a and p21Cip1) and inflammation (Cxcl1, Il1ß, Il6, Mcp1, and Tnfα) markers in small (ileum) and large (caecum and colon) intestine in aged mice (n = 10) compared to age-matched placebo-treated mice (n = 10). Additionally, we examine microbial composition along the intestinal tract in these mice. D+Q-treated mice show significantly lower senescent cell (p16 and p21 expression) and inflammatory (Cxcl1, Il1ß, Il6, Mcp1, and Tnfα expression) burden in small and large intestine compared with control mice. Further, we find specific microbial signatures in ileal, cecal, colonic, and fecal regions that are distinctly modulated by D+Q, with modulation being most prominent in small intestine. Further analyses reveal specific correlation of senescence and inflammation markers with specific microbial signatures. Together, these data demonstrate that the senolytic treatment reduces intestinal senescence and inflammation while altering specific microbiota signatures and suggest that the optimized senolytic regimens might improve health via reducing intestinal senescence, inflammation, and microbial dysbiosis in older subjects.

Dasatinibe para adultos com leucemia linfoblástica aguda cromossomo Philadelphia positivo resistentes/Intolerantes ao mesilato de imatinibe / Dasatinib for Adults with Acute Lymphoblastic Leukemia Philadelphia Chromosome Positive Resistant/Intolerant to Imatinib Mesylate

INTRODUÇÃO: A leucemia linfoblástica aguda (LLA) é uma doença hematológica altamente agressiva, resultante da proliferação e expansão de explosões linfoides no sangue, medula óssea e outros órgãos. A LLA ocorre com uma distribuição bimodal, com um pico precoce nas crianças de 4 a 5 anos, seguido de um segundo pico aos 50 anos de idade, sendo que a incidência mundial é cerca de 1 a 4,75 / 100.000 indivíduos. A proporção entre homens e mulheres é de aproximadamente 1,3:1. A LLA cromossomo Filadélfia positivo (LLA Ph+) é uma variante biologicamente distinta de LLA, classificada pela Organização Mundial da Saúde como LLA com t (9; 22) (q34; q11.2); BCR-ABL1. A LLA Ph+ representa cerca de 20 a 30% das LLA em adultos, e 2 a 3% das LLA em crianças. Quando tratados com quimioterapia isoladamente, os pacientes com LLA Ph+ apresentam um prognóstico ruim com poucos sobreviventes aos cinco anos após o tratamento. O transplante de células hematopoiéticas alogênicas (allo-TMO) proporciona melhores resultados, curando aproximadamente 30 a 60 % dos pacientes com LLA Ph+. A utilização de inibidores da tirosina quinase (ITQ) do BCR-ABL1 (imatinibe, dasatinibe, nilotinibe) no regime de tratamento resultou em taxas de resposta superiores, permitindo assim que mais pacientes procedam ao allo-TMO. No entanto, os pacientes podem adquirir resistência ou intolerância ao tratamento com ITQ, principalmente com mesilato de imatinibe. PERGUNTA: Qual a eficácia (resposta hematológica, reposta citogenética, sobrevida) e a segurança (eventos adversos, toxicidade) do dasatinibe como tratamento de segunda linha em pacientes adultos com LLA Ph+ resistentes ou intolerantes ao mesilato de imatinibe? TECNOLOGIA: dasatinibe (Sprycel). EVIDÊNCIAS CLÍNICAS: Foram avaliados três estudos, sendo um ensaio clínico randomizado de fase III e dois estudo de fase 1/2. Dasatinibe 140 mg uma vez ao dia proporcionou uma sobrevida global mediana (IC95%) de 6,5 (4,6-9,8) meses, e dasatinibe 70 mg duas vezes ao dia proporcionou uma sobrevida de 9,1 (4,8-13,2) meses. A diferença entre os grupos foi não significativa ­ HR: 1,26 (IC95% 0,78-2,04). Houve uma sobrevida livre de progressão mediana (IC95%) de 4,0 (2,9-5,6) meses com o uso de dasatinibe 140 mg uma vez ao dia, e de 3,0 (2,0-4,2) meses com o uso de dasatinibe 70 mg duas vezes ao dia. Esse resultado confere ausência de diferença significante entre os grupos avaliados (0,92; IC95%: 0,58-1,47). Mais de 30% dos indivíduos, independente do estudo em questão, atingiram resposta hematológica principal (MaHR). Em geral, os indivíduos levaram pouco mais de um mês para atingir a MaHR. A resposta hematológica completa (CHR) foi alcançada por 33% dos pacientes que receberam dasatinibe 140 mg/1x dia, e por 25% dos participantes que receberam dasatinibe 70 mg 2x ao dia. A taxa de ausência de leucemia foi variável a depender do estudo (5 a 41%). Resposta citogenética principal (MCyR) foi alcançada por mais de 50% dos indivíduos avaliados, independentemente do estudo em questão. Os eventos adversos de graus 3 ou 4 mais frequentes foram os hematológicos: anemia, leucopenia, trombocitopenia e neutropenia. Conforme avaliação pela abordagem GRADE, a qualidade da evidência foi muito baixa para todos os desfechos avaliados, devido ao grave risco de viés dos estudos individuais e a pequena amostra, o que conferiu baixa precisão nas estimativas. ANÁLISE DE IMPACTO ORÇAMENTÁRIO: Foi elaborado uma análise de impacto orçamentário para estimar os gastos decorrentes da incorporação do dasatinibe no SUS em um horizonte temporal de cinco anos (2021 a 2025). Considerando a população aferida por demanda de quimioterapia de primeira linha para LLA no DATASUS, o impacto orçamentário variou de R$ 7.632.203,49 a R$ 82.217.665,35, a depender da taxa de difusão e fonte de valor de custo (Banco de Preços em Saúde ­ BPS/Sistema Integrado de Administração de Serviços Gerais ­ SIASG ou Câmara de regulação do mercado de Medicamentos ­ CMED). Considerando população estimada com dados epidemiológicos, o impacto orçamentário variou de R$ 4.647.425,94 a R$ 49.310.733,59, a depender da taxa de difusão e fonte de valor de custo (BPS/SIASG e CMED). MONITORAMENTO DO HORIZONTE TECNOLÓGICO (MHT): Os medicamentos flumatinibe (fase 3), inotuzumabe ozogamicin (fase 4) e ponatinibe (fase 3) foram detectados no MHT para pacientes adultos com LLA Ph+ resistentes/intolerantes ao mesilato de imatinibe. CONSIDERAÇÕES FINAIS: As evidências apresentadas mostram que o dasatinibe proporciona boa resposta hematológica e citogenética, podendo apresentar uma mediana de sobrevida global de até 9 meses, em pacientes com LLA Ph+ e resistentes ao mesilato de imatinibe. No entanto, os eventos adversos graves não são raros e os principais são de origem hematológica (leucopenia, neutropenia, anemia, trombocitopenia). Também não foram raros os eventos de interrupção de tratamento ou de redução de dose. Os estudos são pequenos, com baixo rigor metodológico (elevado risco de viés) e não são comparativos. Ademais, a qualidade da evidência foi avaliada como muito baixa para a totalidade dos desfechos, devido ao grave risco de viés e pequena amostra dos estudos individuais, o que conferiu baixa precisão na estimativa dos desfechos, conforme avaliado pela abordagem GRADE. Levando em conta o número de pacientes elegíveis ao tratamento (313 a 522 pacientes a depender do cenário), após a resistência/intolerância ao mesilato de imatinibe, o incremento orçamentário para a ampliação do uso de dasatinibe pode variar entre R$ 20.921.668,18 e R$ 98.479.559,89 em um horizonte temporal de cinco anos (2021-2025). RECOMENDAÇÃO PRELIMINAR DA CONITEC: A Conitec, em sua 91ª reunião ordinária, realizada no dia 07 de outubro de 2020, deliberou que a matéria fosse disponibilizada em consulta pública com recomendação preliminar não favorável à ampliação de uso no SUS do dasatinibe para adultos com leucemia linfoblástica aguda cromossomo Philadelphia positivo resistentes/intolerantes ao mesilato de imatinibe. Considerou-se, entre outrosfatores, que, os estudos apresentados são de baixa qualidade e não possuem comparador, pois são estudos de doses. Além disso, a maioria das agências internacionais não recomendaram a incorporação do medicamento. CONSULTA PÚBLICA: A maioria das contribuições foram de desacordo com a recomendação inicial da Conitec. A ideia central das contribuições é favorável à incorporação do dasatinibe de forma que os pacientes tenham resposta adequada a terapia com ITQ para, então, serem encaminhados ao transplante. A sociedade se manifesta descontente com relação à percebida falta de assistência aos pacientes com LLA Ph+ intolerantes ou com resistência ao imatinibe, em caso de recomendação contrária à incorporação do dasatinibe para esta indicação. RECOMENDAÇÃO FINAL: Os membros da Conitec presentes na 93ª reunião ordinária, no dia 08 de dezembro de 2020, deliberaram por unanimidade recomendar a não ampliação de uso do dasatinibe em adultos com leucemia linfoblástica aguda cromossomo Philadelphia positivo resistentes/intolerantes ao mesilato de imatinibe. Os membros presentes entenderam que não houve mudança no direcionamento da evidência clínica que justificasse uma alteração entre a recomendação preliminar e a recomendação final. Foi assinado o Registro de Deliberação nº 579/2020. DECISÃO: Não ampliar o uso do dasatinibe em adultos com leucemia linfoblástica aguda cromossomo Philadelphia positivo resistentes/intolerantes ao mesilato de imatinibe, no âmbito do Sistema Único de Saúde - SUS, conforme Portaria nº 67, publicada no Diário Oficial da União nº 250, seção 1, página 770, em 31 de dezembro de 2020.

Is breaking of a hydrogen bond enough to lead to drug resistance?

Drug resistance is a serious problem in cancer, viral, bacterial, fungal and parasitic diseases. Examination of crystal structures of protein-drug complexes is often not enough to explain why a certain mutation leads to drug resistance. As an example, the crystal structure of the kinase inhibitor dasatinib bound to the Abl1 kinase shows a hydrogen bond between the drug and residue Thr315 and very few contacts between the drug and residues Val299 and Phe317, yet mutations in those residues lead to drug resistance. In the first case, it is tempting to suggest that the loss of a hydrogen bond leads to drug resistance, whereas in the other two cases it is not known why mutations lead to drug resistance in the first place. We carried out extensive molecular dynamics (MD) simulations and free energy calculations to explain drug resistance to dasatinib from a molecular point of view and show that resistance is due to a multitude of subtle effects. Importantly, our calculations could reproduce the experimental values for the binding energies upon mutations in all three cases and shed light on their origin.

Src-family kinase inhibitors block early steps of caveolin-1-enhanced lung metastasis by melanoma cells.

In advanced stages of cancer disease, caveolin-1 (CAV1) expression increases and correlates with increased migratory and invasive capacity of the respective tumor cells. Previous findings from our laboratory revealed that specific ECM-integrin interactions and tyrosine-14 phosphorylation of CAV1 are required for CAV1-enhanced melanoma cell migration, invasion and metastasis in vivo. In this context, CAV1 phosphorylation on tyrosine-14 mediated by non-receptor Src-family tyrosine kinases seems to be important; however, the effect of Src-family kinase inhibitors on CAV1-enhanced metastasis in vivo has not been studied. Here, we evaluated the effect of CAV1 and c-Abl overexpression, as well as the use of the Src-family kinase inhibitors, PP2 and dasatinib (more specific for Src/Abl) in lung metastasis of B16F10 melanoma cells. Overexpression of CAV1 and c-Abl enhanced CAV1 phosphorylation and the metastatic potential of the B16F10 murine melanoma cells. Alternatively, treatment with PP2 or dasatinib for 2 h reduced CAV1 tyrosine-14 phosphorylation and levels recovered fully within 12 h of removing the inhibitors. Nonetheless, pre-treatment of cells with these inhibitors for 2 h sufficed to prevent migration, invasion and trans-endothelial migration in vitro. Importantly, the transient decrease in CAV1 phosphorylation by these kinase inhibitors prevented early steps of CAV1-enhanced lung metastasis by B16F10 melanoma cells injected into the tail vein of mice. In conclusion, this study underscores the relevance of CAV1 tyrosine-14 phosphorylation by Src-family kinases during the first steps of the metastatic sequence promoted by CAV1. These findings open up potential options for treatment of metastatic tumors in patients in which Src-family kinase activation and CAV1 overexpression favor dissemination of cancer cells to secondary sites.

What happens to intolerant, relapsed or refractory chronic myeloid leukemia patients without access to clinical trials?

ABSTRACT Objective: To assess clinical outcomes of intolerant, relapsed or refractory patients who could not be treated with new tyrosine kinase inhibitors or experimental therapies. Methods: A retrospective cohort of 90 chronic myeloid leukemia patients in all phases of the disease treated with imatinib mesylate as their first TKI therapy, and with dasatinib or nilotinib as the next line of therapy. We evaluated clinical outcomes of these patients, with special focus on the group that needed more than two therapy lines. Results: Thirty-nine percent of patients were refractory or intolerant to imatinib. An 8-year overall survival rate of the patients who went through three or more lines of treatment was significantly lower, compared to those who were able to maintain imatinib as their first-line therapy (83% and 22%, respectively p < 0.01). Decreased overall survival was associated with advanced-phase disease (p < 0.01), failure to achieve major molecular response in first-line treatment (p < 0.01) and interruption of first-line treatment due to any reason (p = 0.023). Failure in achieving complete cytogenetic response and major molecular response and treatment interruption were associated with the progression to the third-line treatment. Conclusion: The critical outcome observed in relapsed, intolerant or refractory chronic phase CML patients reflects the unmet need for this group of patients without an alternative therapy, such as new drugs or experimental therapies in clinical trials. Broader access to newer treatment possibilities is a crucial asset to improve survival among CML patients, especially those refractory or intolerant to first-line therapies.

Management of chronic myeloid leukemia during pregnancy: a retrospective analysis at a single center

ABSTRACT We analyzed the management and outcomes of pregnancies of patients with chronic myeloid leukemia at a single center over fifteen years. Among the 203 CML female patients, there were ten pregnancies in seven women, all of them not planned. In three cases, the chronic myeloid leukemia diagnosis was made during pregnancy. Five patients received tyrosine kinase inhibitors in the first weeks of pregnancy and the drug was interrupted until delivery. One patient lost complete cytogenetic response, and two patients lost the hematological response. A patient with a stable major molecular response had two successful pregnancies without loss of response. There were four premature births. There were no maternal adverse events, fetal malformation or death. All patients received Interferon-alpha during gestation, and two received hydroxyurea for a short period. Leukapheresis was performed in two patients for hyperleukocytosis control. One patient with sickle cell disease died from disease progression six months after delivery. Conclusions: The tyrosine kinase inhibitors ministration should be interrupted during pregnancy. Patients should be advised to achieve a stable and deep molecular response if they plan to conceive, to avoid the risk of disease progression.