Date of Award
9-27-2023
Publication Type
Thesis
Degree Name
M.Sc.
Department
Chemistry and Biochemistry
Keywords
COTI-2;p53 protein;thiosemicarbazone;zinc
Supervisor
John Trant
Rights
info:eu-repo/semantics/openAccess
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Abstract
The tumor protein p53 plays a vital role in regulating protein pathways that determine the fate of cells. Any interference with p53 function can cause disruptive cell proliferation and carcinogenesis. The p53 protein experiences a high frequency of mutation in human cancers, leading to significant research efforts to target mutant p53 and restore the normal functioning of p53. The COTI-2 small molecule, developed by COTINGA Pharmaceuticals through a computational program, has entered Phase I clinical trials. Although the mechanism of action is not fully understood, it has shown considerable promise in targeting cell lines with mutant p53. COTI-2 is believed to induce specific mutants of p53 to refold and restore normal function; however, it may also function as a metal chelator for zinc, although preliminary research from others suggested that this is not the case. We hypothesized that COTI-2 primarily acts as a zinc chelator. We used the extensively studied and validated zinc metallochaperone ZMC1 as a control drug while trying to explore its relationship with zinc. Our findings demonstrate that both COTI-2 and ZMC-1 are effective in killing cancer cells. COTI-2 has been shown to induce cells to undergo apoptotic pathways while targeting them; however, based on our research, it is highly probable that it does not directly interact with the p53 protein while targeting cancer cells. In target engagement assays, we could not observe apparent direct interaction. Furthermore, unlike prior findings regarding zinc and COTI-2, we observed that COTI-2 facilitates intracellular zinc uptake. Additionally, when we prevented the COTI-2 and zinc interaction by using the (COTI-2)2Ru complex, we could not observe COTI-2-triggered cell death. Overall, we have observed that COTI-2 has an affinity to zinc, which can act as a zinc ionophore when administrated to the cells. However, further experiments need to be performed to understand better if it can also balance the p53 protein's zinc. Although our findings have shown that p53 and COTI-2 direct interaction is highly unlikely, it is still possible that it can act through DNA to target p53, especially the site in close proximity to zinc.
Recommended Citation
Simsek, Irem, "A tale of two mechanisms: Is the p53 modulator COTI-2 a zinc chaperone instead?" (2023). Electronic Theses and Dissertations. 9250.
https://scholar.uwindsor.ca/etd/9250