Vitamin D as an Adjuvant in Melanoma Therapy

Abstract

Recent advances in our understanding of the principles underlying melanoma behavior [1,2] have led to an explosion in the strategies proposed to treat cutaneous metastatic melanomas [1–3]. In effect, new molecules and treatment modalities are being developed [1–4] to treat this devastating disease. Unfortunately, these strategies only retain efficacy for a few months before the disease relapses, plus the drugs involved have toxic side effects and are very expensive [5], so the only reliable therapy is proper surgical excision when the disease is localized to the skin. Therefore, the management of metastatic melanoma represents a significant challenge for both clinicians and patients, and there is an urgent need to clarify the mechanisms responsible for resistance to therapy against metastatic melanoma [5]. These challenges undoubtedly will be addressed by basic and clinical melanoma researchers for years to come. However, to help patients with these devastating diseases we need immediate, nontoxic and economical adjuvant strategies for improvement of patient survival, with relatively limited side effects. These requirements can be met by the application of natural products and their derivatives in an educated fashion, to not only restrict melanoma growth and progression but also to restore the body's homeostatic capabilities to control tumor behavior [5]. Examples of such compounds are vitamin D that can be activated in the body by the classical pathway to 1α,25-dihydroxyvitamin D (1,25(OH) 2 D) [6,7], and newly