IL-20 Subfamily Biological Effects: Mechanistic Insights and Therapeutic Perspectives in Cancer

The interleukin-20 (IL-20) cytokine subfamily, a subset of the IL-10 superfamily, includes IL-19, IL-20, IL-22, IL-24, and IL-26. Recently, their involvement in cancer biology has gained attention, particularly due to their impact on the tumor microenvironment (TME). Notably, IL-20 subfamily cytokines can exert both pro-tumorigenic and anti-tumorigenic effects, depending on the context. For example, IL-22 promotes tumor growth by enhancing cancer cell proliferation and protecting against apoptosis, whereas IL-24 demonstrates anti-tumor activity by inducing cancer cell death and inhibiting metastasis. Additionally, these cytokines influence macrophage polarization—an essential factor in the immune landscape of tumors—thereby modulating the inflammatory environment and immune evasion strategies. Understanding the dual role of IL-20 subfamily cytokines within the TME and their interactions with cancer cell hallmarks presents a promising avenue for therapeutic development. Interleukin-20 receptor antagonists are being researched for their role in cancer therapy, since they potentially inhibit tumor growth and progression. This review explores the relationship between IL-20 cytokines and key cancer-related processes, including growth and proliferative advantages, angiogenesis, invasion, metastasis, and TME support. Further research is necessary to unravel the specific mechanisms underlying their contributions to tumor progression and to determine their potential for targeted therapeutic strategies.