Retinoids Selectively Induce Gut-Homing Properties In Cutaneous T Cell Lymphoma (Ctcl) Cells

Introduction: Cutaneous T cell lymphoma (CTCL) is a heterogeneous group of malignancies characterized by accumulation of malignant T cells within skin. Retinoids, metabolic derivatives and synthetic analogs of vitamin A, naturally imprint gut homing in T lymphocytes by inducing integrin alpha4beta7 and CCR9 expression which effectively targets the immune cells away from the skin niche. Although successfully used in CTCL therapy for decades, the therapeutic mechanism of action of retinoids in resolving CTCL remains largely speculative. How the natural role of retinoids in immune cell trafficking relates or applies to therapeutic effectiveness in CTCL has not been addressed and merits investigation. Here we provide the first evidence that the natural role of retinioids in governing immune cell localization to the gut accounts for their therapeutic benefit in CTCL.