The role of oxygen as a stressor, metabolite and signalling molecule and its effect on cell proliferation

This thesis is a comparative study of how different oxygen concentrations alter the proliferation, energy metabolism, protection against oxidized molecules, and phenotype of a variety of cancer cell lines. It examines three different oxygen concentrations and their impact, utilizing expansion assays, analysis of genetic expression of enzymes involved in energy metabolism and oxidative protection, and microscopic images. What was revealed was that the level of oxygen has a varied effect on cellular proliferation depending on cell type, the details of which need to be explored. Additionally, the varied oxygen conditions also showed inconclusive evidence of a role in phenotype change, oxidative protection and energy metabolism, while indicating pre-programmed differences in energy metabolism and oxidative protection gene expression that was dependent on cell type. The results of this study confirm that cell types behave differently and it provides potential mechanisms of treatment