Nitro-Deficient Niclosamide Confers Reduced Genotoxicity and Retains Mitochondrial Uncoupling Activity for Cancer...

Area of Science:

• Biochemistry
• Pharmacology
• Cancer Biology

Background:

• Niclosamide, an anthelmintic, shows potential in cancer therapy, particularly in p53-deficient tumors.
• Its mechanism of action and potential genotoxicity require further elucidation for clinical application.
• The aniline 4'-NO2 group's role in niclosamide's activity is under investigation.

Purpose of the Study:

• To characterize the contribution of the aniline 4'-NO2 group to niclosamide's cellular activities.
• To investigate the genotoxic effects of niclosamide and its analogues.
• To assess the impact of the nitro group on niclosamide's anti-tumor selectivity and efficacy.

Main Methods:

• Functional characterization of niclosamide and its analogue ND-Nic.
• Assessment of genome-wide DNA damage using markers like γH2AX.
• Lipidomics profiling to analyze metabolic changes.
• Quantitative drug sensitivity scoring for p53-deficient cancer models.

Main Results:

• Niclosamide induces DNA damage, separate from its mitochondrial uncoupling effects.
• Eliminating the nitro group (ND-Nic) reduced DNA damage while maintaining anti-tumor activity via calcium signaling and arachidonic acid metabolism.
• ND-Nic demonstrated enhanced target selectivity for p53-deficient cancers.
• Lipidomics confirmed conserved metabolite profiles between niclosamide and ND-Nic treatments.

Conclusions:

• The aniline 4'-NO2 group contributes to niclosamide's genotoxicity, which is uncoupled from its anti-tumor effects.
• Modifying niclosamide by removing the nitro group can enhance anti-tumor selectivity and potentially reduce genotoxic side effects.
• Further research into niclosamide analogues is warranted to optimize clinical efficacy and safety.