Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Pharmaceutics ; 14(10)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36297430

RESUMEN

Zanubrutinib (ZAN) is a Bruton's tyrosine kinase inhibitor recently approved for the treatment of some non-Hodgkin lymphomas. In clinical trials, ZAN is often combined with standard anthracycline (ANT) chemotherapy. Although ANTs are generally effective, drug resistance is a crucial obstacle that leads to treatment discontinuation. This study showed that ZAN counteracts ANT resistance by targeting aldo-keto reductase 1C3 (AKR1C3) and ATP-binding cassette (ABC) transporters. AKR1C3 catalyses the transformation of ANTs to less potent hydroxy-metabolites, whereas transporters decrease the ANT-effective concentrations by pumping them out of the cancer cells. In our experiments, ZAN inhibited the AKR1C3-mediated inactivation of daunorubicin (DAUN) at both the recombinant and cellular levels. In the drug combination experiments, ZAN synergistically sensitised AKR1C3-expressing HCT116 and A549 cells to DAUN treatment. Gene induction studies further confirmed that ZAN did not increase the intracellular level of AKR1C3 mRNA; thus, the drug combination effect is not abolished by enzyme induction. Finally, in accumulation assays, ZAN was found to interfere with the DAUN efflux mediated by the ABCB1, ABCG2, and ABCC1 transporters, which might further contribute to the reversal of ANT resistance. In summary, our data provide the rationale for ZAN inclusion in ANT-based therapy and suggest its potential for the treatment of tumours expressing AKR1C3 and/or the above-mentioned ABC transporters.

2.
Cas Lek Cesk ; 161(1): 24-27, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35354291

RESUMEN

Shortly after the WHOs first notice a suspected case of omicron SARS-CoV-2 was reported in Liberec, Czech Republic. The primary goal of the following actions was to test the presence of the variant and stop the spread of the virus variant. On November 25 a sixty-year-old lady, who had recently returned from Namibia, visited a GP with flu-like symptoms and a rash on her chest. The antigen test was positive for SARS-CoV-2, a PCR test was planned. At that time, it was not known that a new variant of concern was spreading from Africa. On November 26 in the morning the GP announced a suspected omicron case to the Regional public health authority, who organized the following steps. A mobile sampling team was sent to the patient's home immediately, sample transported into the regional hospital and analyzed with the help of the national reference laboratory. The captured virus SARS-CoV-2 fitted the description of the omicron variant, was shared in the GISAID database and named hCoV-19/Czech Republic/KNL_2021-110119140/2021. Contact tracing was started immediately, eleven persons were tested and quarantined. One of them positive with no further spread. It is the first documented omicron case in the Czech Republic and one of the first cases in Europe, with an excellent systemic response to the alert. The laboratory was able to detect the omicron variant instantly after the request. This case also demonstrates how easily the virus spreads on long distances and how important it might be to increase the uptake of the booster vaccine.


Asunto(s)
COVID-19 , SARS-CoV-2 , Europa (Continente) , Femenino , Humanos , Persona de Mediana Edad , Investigación
3.
Biochem Pharmacol ; 192: 114710, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34339712

RESUMEN

Bcr-Abl tyrosine kinase inhibitors significantly improved Philadelphia chromosome-positive leukaemia therapy. Apart from Bcr-Abl kinase, imatinib, dasatinib, nilotinib, bosutinib and ponatinib are known to have additional off-target effects that might contribute to their antitumoural activities. In our study, we identified aldo-keto reductase 1B10 (AKR1B10) as a novel target for dasatinib. The enzyme AKR1B10 is upregulated in several cancers and influences the metabolism of chemotherapy drugs, including anthracyclines. AKR1B10 reduces anthracyclines to alcohol metabolites that show less antineoplastic properties and tend to accumulate in cardiac tissue. In our experiments, clinically achievable concentrations of dasatinib selectively inhibited AKR1B10 both in experiments with recombinant enzyme (Ki = 0.6 µM) and in a cellular model (IC50 = 0.5 µM). Subsequently, the ability of dasatinib to attenuate AKR1B10-mediated daunorubicin (Daun) resistance was determined in AKR1B10-overexpressing cells. We have demonstrated that dasatinib can synergize with Daun in human cancer cells and enhance its therapeutic effectiveness. Taken together, our results provide new information on how dasatinib may act beyond targeting Bcr-Abl kinase, which may help to design new chemotherapy regimens, including those with anthracyclines.


Asunto(s)
Aldo-Ceto Reductasas/antagonistas & inhibidores , Dasatinib/administración & dosificación , Daunorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/administración & dosificación , Células A549 , Aldo-Ceto Reductasas/química , Aldo-Ceto Reductasas/metabolismo , Antineoplásicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/fisiología , Proteínas de Fusión bcr-abl/química , Proteínas de Fusión bcr-abl/metabolismo , Células HCT116 , Humanos , Simulación del Acoplamiento Molecular , Estructura Secundaria de Proteína
4.
Cancers (Basel) ; 12(12)2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33322571

RESUMEN

Over the last few years, aldo-keto reductase family 1 member C3 (AKR1C3) has been associated with the emergence of multidrug resistance (MDR), thereby hindering chemotherapy against cancer. In particular, impaired efficacy of the gold standards of induction therapy in acute myeloid leukaemia (AML) has been correlated with AKR1C3 expression, as this enzyme metabolises several drugs including anthracyclines. Therefore, the development of selective AKR1C3 inhibitors may help to overcome chemoresistance in clinical practice. In this regard, we demonstrated that Bruton's tyrosine kinase (BTK) inhibitors ibrutinib and acalabrutinib efficiently prevented daunorubicin (Dau) inactivation mediated by AKR1C3 in both its recombinant form as well as during its overexpression in cancer cells. This revealed a synergistic effect of BTK inhibitors on Dau cytotoxicity in cancer cells expressing AKR1C3 both exogenously and endogenously, thus reverting anthracycline resistance in vitro. These findings suggest that BTK inhibitors have a novel off-target action, which can be exploited against leukaemia through combination regimens with standard chemotherapeutics like anthracyclines.

5.
J Hist Biol ; 51(1): 69-106, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28321591

RESUMEN

The sixteenth century could be understand as a period of renaissance of interest in nature and as a period of development of natural history as a discipline. The spreading of the printing press was connected to the preparation of new editions of Classical texts and to the act of correcting and commenting on these texts. This forced scholars to confront texts with living nature and to subject it to more careful investigation. The discovery of America uncovered new horizons and brought new natural products, which were exotic and unknown to Classical tradition. The aim of this study is to compare strategies and categories, which were used in describing plants of the Old and the New World. Attention will be paid to the first reactions to the new flora, to the methods of naming and describing plants, to the ways of gaining knowledge about plants from local sources or by means of one's own observation. The confrontation with novelty puts naturalists in the Old World and in the New World in a similar situation. It reveals the limits of traditional knowledge based on Classical authorities. A closer investigation, however, brings to light not only the sometimes unexpected similarities, but also the differences which were due to the radical otherness of American plants.


Asunto(s)
Libros Ilustrados/historia , Botánica/historia , Historia Natural/historia , Obras de Referencia , Europa (Continente) , Historia del Siglo XVI , Plantas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...