The role of the cytochrome P450-enzyme complex protein factors and other oxidoreductases in the mechanisnms of acquired cancer drug resistance / Daniel Crispim ; orient. Michel Kranendonk, Francisco Esteves
Main Author Crispim, Daniel Filipe Grilo Secondary Author Kranendonk, MichelEsteves, Francisco Language Inglês. Country Portugal. Publication Lisboa : NOVA Medical School, Universidade NOVA de Lisboa, 2023 Description 118 p. Dissertation Note or Thesis: Dissertação de Mestrado
Bioquímica para a Saúde
2023
Faculdade de Ciências Médicas, Universidade NOVA de Lisboa
Abstract Drug resistance (DR) is a major challenge in cancer therapy, estimated to contribute in 90% to cancer-related fatalities. This study addresses the underexplored topic of drug metabolism’s role in DR development, particularly at subtherapeutic levels of doxorubicin (DOX), one of the most widely used chemotherapeutics. Cells from the breast cancer (BC) MCF-7 cell line, resistant to specific DOX concentrations, were used to develop three-dimensional (3D) spheroid models. Spheroids were comprehensively characterized according to the MISpheroID guidelines, and a detailed examination of these 3D structures and respective cells was conducted, focusing on their size, morphology, oxidative stress, and cell cycle distribution. Expression levels of 92 phase I drug metabolizing enzymes and the activities of specific CYP isoforms were assessed, both in DOX-sensitive and resistant cells. We identified a signature of 24 significantly differentially expressed genes in drug resistant cells, most of which had previously been correlated with chemoresistance and/or tumor progression in BC patients. An enhanced CYP3A-dependent metabolism was also detected in DOX-resistant cells. The detected upregulation of CYP4B1, CYP26B1, FDXR, FMO5, and PAH, as well as augmented CYP3A metabolism, had already been observed in a previous report from our laboratory, using monolayer cultures of drug-resistant MCF-7 cells. These outcomes highlight the potential use of encountered expression and activity profiles as predictive markers for DOX resistance development. When comparing results obtained from monolayer with the spheroid culture approach, several specific differences were noticeable, demonstrating the critical importance of spatial organization on enzyme expression and activity in DOX resistance. In summary, our data reveals an intricate link between the expression and activity of drug metabolizing enzymes and the development of acquired resistance to DOX in MCF-7 cells. Additionally, these results underscore the dynamic nature of this development, transiently dependent on multiple pathways such as drug-, arachidonic acid-, retinoic acid-, and vitamin D-metabolisms Topical name Drug Resistance, Neoplasm
Academic Dissertation Online Resources Click here to access the eletronic resource http://hdl.handle.net/10362/161196
| Item type | Current location | Call number | url | Status | Date due | Barcode |
|---|---|---|---|---|---|---|
| Documento Eletrónico | Biblioteca NMS|FCM online | RUN | http://hdl.handle.net/10362/161196 | Available | 20240017 |
Dissertação de Mestrado Bioquímica para a Saúde 2023 Faculdade de Ciências Médicas, Universidade NOVA de Lisboa
Drug resistance (DR) is a major challenge in cancer therapy, estimated to contribute in 90% to cancer-related fatalities. This study addresses the underexplored topic of drug metabolism’s role in DR development, particularly at subtherapeutic levels of doxorubicin (DOX), one of the most widely used chemotherapeutics. Cells from the breast cancer (BC) MCF-7 cell line, resistant to specific DOX concentrations, were used to develop three-dimensional (3D) spheroid models. Spheroids were comprehensively characterized according to the MISpheroID guidelines, and a detailed examination of these 3D structures and respective cells was conducted, focusing on their size, morphology, oxidative stress, and cell cycle distribution. Expression levels of 92 phase I drug metabolizing enzymes and the activities of specific CYP isoforms were assessed, both in DOX-sensitive and resistant cells. We identified a signature of 24 significantly differentially expressed genes in drug resistant cells, most of which had previously been correlated with chemoresistance and/or tumor progression in BC patients. An enhanced CYP3A-dependent metabolism was also detected in DOX-resistant cells. The detected upregulation of CYP4B1, CYP26B1, FDXR, FMO5, and PAH, as well as augmented CYP3A metabolism, had already been observed in a previous report from our laboratory, using monolayer cultures of drug-resistant MCF-7 cells. These outcomes highlight the potential use of encountered expression and activity profiles as predictive markers for DOX resistance development. When comparing results obtained from monolayer with the spheroid culture approach, several specific differences were noticeable, demonstrating the critical importance of spatial organization on enzyme expression and activity in DOX resistance. In summary, our data reveals an intricate link between the expression and activity of drug metabolizing enzymes and the development of acquired resistance to DOX in MCF-7 cells. Additionally, these results underscore the dynamic nature of this development, transiently dependent on multiple pathways such as drug-, arachidonic acid-, retinoic acid-, and vitamin D-metabolisms
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