Influence of selenium on 3-methylcholanthrene induced skin carcinogenesis in mice

Area of Science:

• Oncology
• Toxicology
• Biochemistry

Background:

• 3-methylcholanthrene (MCA) is a known carcinogen used to induce skin tumors in experimental models.
• Selenium is a trace element with potential chemopreventive properties against various cancers.

Purpose of the Study:

• To investigate the effect of selenium treatment on the incidence and development of skin papillomas/tumors induced by MCA in male ICRC mice.
• To explore the underlying mechanisms by which selenium may exert its protective effects.

Main Methods:

• Male ICRC mice were treated with selenium.
• Skin tumors were induced by topical application of 3-methylcholanthrene (MCA).
• Tumor incidence, burden, and latent period were assessed. Aryl hydrocarbon hydroxylase (AHH) and glutathione S-transferase (GST) activities were measured in skin and liver tissues.

Main Results:

• Selenium treatment significantly decreased the percentage incidence and tumor burden of skin papillomas/tumors.
• The latent period for tumor induction was significantly increased in selenium-treated mice.
• No significant influence of selenium was observed on aryl hydrocarbon hydroxylase (AHH) activity in skin and liver.
• A significant increase in glutathione S-transferase (GST) activity was observed in selenium-treated mice.

Conclusions:

• Selenium treatment demonstrates chemopreventive effects against MCA-induced skin carcinogenesis in mice.
• The protective mechanism of selenium likely involves the enhancement of detoxication pathways, specifically via increased glutathione S-transferase (GST) activity.
• Selenium does not appear to suppress carcinogenesis by altering the activation or inactivation of the carcinogen (MCA).