Bioenergetics of cancer cells in anoxia and role of the miRNAs in melanoma resistance to targeted therapies

Costanzini, Anna (2019) Bioenergetics of cancer cells in anoxia and role of the miRNAs in melanoma resistance to targeted therapies, [Dissertation thesis], Alma Mater Studiorum Università di Bologna. Dottorato di ricerca in Scienze biomediche e neuromotorie, 31 Ciclo.
Documenti full-text disponibili:
[img] Documento PDF (English) - Accesso riservato fino a 31 Dicembre 2021 - Richiede un lettore di PDF come Xpdf o Adobe Acrobat Reader
Disponibile con Licenza: Salvo eventuali più ampie autorizzazioni dell'autore, la tesi può essere liberamente consultata e può essere effettuato il salvataggio e la stampa di una copia per fini strettamente personali di studio, di ricerca e di insegnamento, con espresso divieto di qualunque utilizzo direttamente o indirettamente commerciale. Ogni altro diritto sul materiale è riservato.
Download (14MB) | Contatta l'autore

Abstract

Tumours are characterized by a metabolic rewiring that helps transformed cells to survive in harsh conditions. The endogenous inhibitor of the ATP-synthase IF1 is overexpressed in several tumours and it has been proposed to drive metabolic adaptation. In ischemic normal-cells, IF1 acts limiting the ATP consumption by the reverse activity of the ATP-synthase, activated by ΔΨm collapse. Conversely, IF1 role in cancer cells is still unclear. It has been proposed that IF1 favours cancer survival by preventing energy dissipation in low oxygen availability, a frequent condition in solid tumours. Our previous data proved that in cancer cells hypoxia does not abolish ΔΨm, avoiding the ATP-synthase reversal and IF1 activation. In this study, we investigated the bioenergetics of cancer cells in conditions mimicking anoxia to evaluate the possible role of IF1. Data obtained indicate that also in cancer cells the ΔΨm collapse induces the ATP-synthase reversal and its inhibition by IF1. Moreover, we demonstrated that upon uncoupling conditions, IF1 favours cancer cells growth preserving ATP levels and energy charge. We also showed that in these conditions IF1 favours the mitochondrial mass renewal, a mechanism we proposed driving apoptosis-resistance. Cancer adaptability is also associated with the onset of therapy resistance, the major challenge for melanoma treatment. Recent studies demonstrated that miRNAs dysregulation drive melanoma progression and drug-resistance by regulating tumour-suppressor and oncogenes. In this context, we attempted to identify and characterize miRNAs driving resistance to vemurafenib in patient-derived metastatic melanoma cells BRAFV600E-mutated. Our results highlighted that several oncogenic pathways are altered in resistant cells, indicating the complexity of both drug-resistance phenomena and miRNAs action. Profiling analysis identified a group of dysregulated miRNAs conserved in vemurafenib-resistance cells from distinct patients, suggesting that they ubiquitously drive drug-resistance. Functional studies performed with a first miRNA confirmed its pivotal role in resistance towards vemurafenib.

Abstract
Tipologia del documento
Tesi di dottorato
Autore
Costanzini, Anna
Supervisore
Co-supervisore
Dottorato di ricerca
Ciclo
31
Coordinatore
Settore disciplinare
Settore concorsuale
Parole chiave
IF1, anoxia, cancer cells,bioenergetics, miRNAs, drug resistance, vemurafenib, metastatic melanoma
URN:NBN
Data di discussione
12 Aprile 2019
URI

Altri metadati

Gestione del documento: Visualizza la tesi

^