Comparative Study of Cutaneous Squamous Cell Carcinogenesis in Different Hairless Murine Models

Area of Science:

• Dermatology
• Oncology
• Genetics

Background:

• Non-melanoma skin cancer incidence is rising globally.
• Squamous cell carcinoma (SCC) pathogenesis requires further in vivo investigation.
• Existing hairless mouse models for SCC lack comparative analysis.

Purpose of the Study:

• To compare the efficacy of different hairless mouse models in inducing squamous cell carcinoma.
• To investigate the role of melanin, hypercholesterolemia, and immunosuppression in SCC development.
• To assess proteasome activity in relation to SCC formation.

Main Methods:

• Four mouse strains (SKH-hr1, SKH-hr2, SKH-hr2+ApoE, Nude) were exposed to UVA/UVB radiation.
• Doses increased from 1 to 3 Minimal Erythemal Doses (MED).
• Evaluations included clinical, biophysical, proteasome activity, and histopathological assessments.

Main Results:

• SKH-hr1 mice developed actinic keratosis, not invasive SCC.
• SKH-hr2 and SKH-hr2+ApoE models showed higher incidence and intensity of papilloma and aggressive SCC.
• SKH-hr2+ApoE mice exhibited upregulated proteasome activity; histopathology confirmed invasive SCC in SKH-hr2 and SKH-hr2+ApoE models.

Conclusions:

• SKH-hr2+ApoE and SKH-hr2 mice are optimal for SCC carcinogenesis research.
• SKH-hr1 mice are least suitable despite being albino.
• Proteasome activity is implicated in squamous cell carcinogenesis.