Related Experiment Video
Updated: Jun 24, 2025
Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
Structural basis of p53 inactivation by cavity-creating cancer mutations and its implications for the development of
Dimitrios-Ilias Balourdas1,2, Anja M Markl1, Andreas Krämer1,2
1Institute of Pharmaceutical Chemistry, Goethe University, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany.
Abstract:
The cavity-creating p53 cancer mutation Y220C is an ideal paradigm for developing small-molecule drugs based on protein stabilization. Here, we have systematically analyzed the structural and stability effects of all oncogenic Tyr-to-Cys mutations (Y126C, Y163C, Y205C, Y220C, Y234C, and Y236C) in the p53 DNA-binding domain (DBD). They were all highly destabilizing, drastically lowering the melting temperature of the protein by 8-17 °C. In contrast, two non-cancerous mutations, Y103C and Y107C, had only a moderate effect on protein stability. Differential stabilization of the mutants upon treatment with the anticancer agent arsenic trioxide and stibogluconate revealed an interesting proximity effect. Crystallographic studies complemented by MD simulations showed that two of the mutations, Y234C and Y236C, create internal cavities of different size and shape, whereas the others induce unique surface lesions. The mutation-induced pockets in the Y126C and Y205C mutant were, however, relatively small compared with that of the already druggable Y220C mutant. Intriguingly, our structural studies suggest a pronounced plasticity of the mutation-induced pocket in the frequently occurring Y163C mutant, which may be exploited for the development of small-molecule stabilizers. We point out general principles for reactivating thermolabile cancer mutants and highlight special cases where mutant-specific drugs are needed for the pharmacological rescue of p53 function in tumors.
Insights
The p53 Y220C mutation creates a cavity, making it a target for stabilizing drugs. Researchers studied all Tyr-to-Cys mutations in p53, finding most destabilize the protein, but some pockets offer potential for developing new cancer therapies.
Area of Science:
- Biochemistry
- Structural Biology
- Cancer Research
Background:
- The p53 tumor suppressor protein is frequently mutated in cancer.
- The Y220C mutation in p53 creates a cavity, serving as a model for drug development.
- Understanding the structural and stability effects of other p53 mutations is crucial for targeted therapies.
Purpose of the Study:
- To systematically analyze the structural and stability impacts of all oncogenic Tyr-to-Cys mutations in the p53 DNA-binding domain (DBD).
- To investigate the potential for developing small-molecule stabilizers for thermolabile p53 mutants.
- To identify general principles for reactivating mutant p53 and special cases requiring mutant-specific drugs.
Main Methods:
- Systematic analysis of p53 Tyr-to-Cys mutations (Y126C, Y163C, Y205C, Y220C, Y234C, Y236C).
- Differential scanning fluorimetry to assess protein melting temperatures and stability.
- Crystallography and molecular dynamics (MD) simulations to determine structural effects and pocket formation.
- Treatment with anticancer agents (arsenic trioxide, stibogluconate) to observe differential stabilization.
Main Results:
- All analyzed oncogenic Tyr-to-Cys mutations significantly destabilized p53 (lowering melting temperature by 8-17°C).
- Mutations Y234C and Y236C created internal cavities; others induced surface lesions.
- The Y220C mutant pocket is druggable, while the Y163C mutant shows pocket plasticity suitable for stabilizer development.
- Non-cancerous mutations Y103C and Y107C had moderate effects on protein stability.
Conclusions:
- Most oncogenic p53 Tyr-to-Cys mutations destabilize the protein, creating unique structural alterations.
- Specific mutation-induced pockets, like in Y220C and Y163C, offer opportunities for developing small-molecule stabilizers.
- These findings provide principles for reactivating thermolabile p53 mutants and highlight the need for mutant-specific drugs in cancer therapy.
Related Concept Videos
02:23Abnormal Proliferation
01:31The Intrinsic Apoptotic Pathway
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
01:12Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
02:37DNA Damage can Stall the Cell Cycle
02:21Cancers Originate from Somatic Mutations in a Single Cell