- Title
- Elucidation of the effect of cannabinoids on ER stress to determine their molecular mechanism of action in breast cancer cells
- Creator
- De la Harpe, Amy
- Subject
- Endoplasmic reticulum -- Pathophysiology
- Subject
- Breast -- Cancer -- Research
- Date Issued
- 2020
- Date
- 2020
- Type
- Thesis
- Type
- Masters
- Type
- MSc
- Identifier
- http://hdl.handle.net/10948/48213
- Identifier
- vital:40525
- Description
- Endoplasmic reticulum (ER) stress is defined as an imbalance between the ER’s protein-folding load and folding capacity. ER stress is induced by various physiological conditions and subsequently triggers the activation of the unfolded protein response (UPR) to re-establish homeostasis and promote cell survival. However, under severe or chronic stress, apoptosis is induced. Normal cells generally do not experience ER stress; however, stressful conditions in the tumour micro-environment facilitates chronic ER stress and UPR activation, which plays a pivotal role in tumour survival. Exacerbation of pre-existing ER stress can trigger cancer cell death, with a minimal effect on normal cells. Currently, no high-throughput method exists to detect and quantify ER stress in cell lines. This study showed that Thioflavin T, a fluorescent dye that binds to misfolded protein aggregates, can be used for the high-throughput detection of ER stress, and provides several advantages over currently used methods. Current literature suggests that cannabinoid treatment may induce cancer cell death via ER stress, however little is known about the mechanism of induction. This study proposed a mechanism that occurs via the influx of Ca2+ via the vanilloid receptor 1 (TRPV1), and subsequent ROS production, which affects protein folding. ER stress was induced using various cannabinoids and measured using Thioflavin T and western blot analysis. The effect of cannabinoid treatment on ROS production and the intracellular Ca2+ concentration was measured. Cannabidiol (CBD) was the most potent ER stress inducer, significantly increasing Ca2+ and ROS accumulation; however, the level of accumulated Ca2+ across cell lines varied, which may be due to the differences in the TRPV1 expression and localization. Concomitant treatment of CBD with an antioxidant significantly increased cell viability and decreased ER stress induction in the MCF7 cell line. Concomitant treatment with a TRPV1 antagonist increased viability in this cell line. In conclusion, the results suggested that CBD may induce ER stress via Ca2+ influx through the TRPV1 receptor, thereby elevating intracellular ROS levels and disrupting protein folding.
- Format
- xix, 173 leaves
- Format
- Publisher
- Nelson Mandela University
- Publisher
- Faculty of Science
- Language
- English
- Rights
- Nelson Mandela University
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Collections
NMU School of BioMolecular and Chemical Sciences
| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | de le Harpe, AL 214150658 Dissertation April 2020.pdf | 7 MB | Adobe Acrobat PDF | View Details Download |