Skip to Main content Skip to Navigation
Theses

Radiosensitizing effect of AGuIX® in Head and Neck Squamous Cell Carcinoma (HNSCC) : from cellular uptake to subcellular damage

Abstract : Head and Neck Squamous Cell Carcinoma is ranked among the top ten deadliest cancers due to its high radioresistance and recurrence. One radiosensitizing strategy is the use of high-Z metal nanoparticles. In this study, ultrasmall gadolinium-based nanoparticles, AGuIX®, were used for their potential as a radiosensitizing agent. The objectives of this work were to determine the radiosensitizing conditions of AGuIX® in an HNSCC cell model, their localization after uptake, and the biological consequences generated at the subcellular level after the combined treatment. A preliminary proteomic approach was initiated in order to identify potential molecular targets involved in radiosensitization. The treatment of SQ20B cells with 0.8mM Gd for 24h resulted in a dose enhancement factor (DEF) of 1.3. AGuIX® were predominantly localized in lysosomes. The overproduction of radical oxygen species following AGuIX® + radiation was intimately involved in the radiosensitization, although largely subdued by the high level of endogenous antioxidant defenses. Autophagy was specifically triggered after the combined treatment, while other irradiation-induced cell deaths remained unchanged. The number of complex, residual double strand breaks (DSBs) was specifically increased with AGuIX® combined to radiation. Lastly, our preliminary proteomic analysis allowed the isolation of potential molecular targets with great promise. Collectively, it seems that the radiosensitizing effect observed in this work may result from a combination of events.Future work is required to understand the mechanisms linking lysosomes-entrapped AGuIX® with the upregulation of autophagic cell death after radiation
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-01844471
Contributor : Abes Star :  Contact
Submitted on : Friday, December 27, 2019 - 1:01:16 AM
Last modification on : Saturday, September 5, 2020 - 3:24:33 AM
Long-term archiving on: : Saturday, March 28, 2020 - 12:24:13 PM

File

TH2018SIMONETSTEPHANIE.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01844471, version 2

Collections

Citation

Stéphanie Simonet. Radiosensitizing effect of AGuIX® in Head and Neck Squamous Cell Carcinoma (HNSCC) : from cellular uptake to subcellular damage. Cellular Biology. Université de Lyon, 2018. English. ⟨NNT : 2018LYSE1042⟩. ⟨tel-01844471v2⟩

Share

Metrics

Record views

542

Files downloads

245