IL-23 Inhibits Melanoma Development by Augmenting DNA Repair and Modulating T Cell Subpopulations

Area of Science:

• Immunology
• Dermatology
• Oncology

Background:

• Interleukin-12 (IL-12) and Interleukin-23 (IL-23) are implicated in keratinocyte cancers.
• Their roles in pigmented lesions and melanoma progression are understudied.

Purpose of the Study:

• To investigate the specific roles of IL-12 and IL-23 in melanomagenesis.
• To determine the impact of these cytokines on nevus development and melanoma progression.

Main Methods:

• Utilized knockout mice lacking IL-12p35, IL-23p19, or IL-12/IL-23p40 in a melanomagenesis protocol.
• Assessed susceptibility to nevus initiation, transformation, tumorigenicity, and metastasis.
• Investigated direct effects of IL-23 on melanocytes and its modulation of the cutaneous microenvironment.
• Examined the impact of neutralizing antibodies against IFN-γ and IL-17.

Main Results:

• IL-23 is essential for melanocyte homeostasis and DNA repair in IL-23R+ melanocytes.
• IL-12 supports nevus development.
• IL-23 modulates the skin microenvironment by reducing regulatory T cells, IFN-γ, and IL-10.
• Neutralizing IFN-γ, but not IL-17, inhibited nevus development.

Conclusions:

• IL-23 plays a protective role in melanocyte DNA repair and homeostasis.
• IL-12 promotes nevus formation, suggesting distinct roles in melanoma development.
• Targeting IFN-γ may be a therapeutic strategy for inhibiting nevus development.