Enhancing Repair of Oxidative DNA Damage with Small-Molecule Activators of MTH1

Area of Science:

• Biochemistry
• Molecular Biology
• Cancer Research

Background:

• Impaired DNA repair mechanisms are linked to increased cancer incidence.
• Targeting DNA repair pathways presents a potential strategy for cancer inhibition.
• Oxidative stress generates mutagenic DNA lesions, such as 8-oxo-2'-deoxyguanosine (8-oxo-dG).

Purpose of the Study:

• To investigate whether tyrosine kinase (TK) inhibitors can modulate the activity of the DNA repair enzyme Human MutT Homolog 1 (MTH1).
• To explore the potential of MTH1 activators as a strategy for cancer risk reduction.

Main Methods:

• Screening of selected tyrosine kinase inhibitors for MTH1 activation.
• Structural optimization of TK inhibitor analogues to enhance MTH1 activity.
• Assessing the impact of compounds on MTH1 enzyme activity and cellular 8-oxo-dG levels.

Main Results:

• Selected TK inhibitors, including nilotinib, were identified as MTH1 activators.
• An optimized analogue, SU0448, demonstrated significant MTH1 activation (1000% at 10 μM).
• SU0448 treatment reduced levels of 8-oxo-dG in cellular DNA, indicating decreased mutagenic lesions.

Conclusions:

• MTH1 activators, derived from TK inhibitors, can enhance DNA repair capacity.
• This approach may offer a novel strategy to suppress tumorigenesis by mitigating DNA damage.
• Targeting MTH1 represents a promising avenue for cancer prevention in high-risk individuals.