Hormonal Regulation of Cutaneous Melanoma: A Brief Review of In Vivo and In Vitro Studies and Its Clinical Implication

Skin is an endocrine organ. Skin produces various hypothalamic, pituitary, adrenal and sex steroid hormones. This raises the question whether skin cancer melanoma is a hormone dependent cancer. But, a review of in-vivo and in-vitro studies suggested that melanoma could be a hormone responsive cancer or hormone sensitive cancer. In fact, previous clinical study showed that menstruating females were better protected in melanoma than post-menopausal women and men of any age. However, the study did not show any direct effect of steroid hormone on melanoma cells. Our in-vitro study showed that progesterone, a female sex hormone significantly inhibited human melanoma (BLM) cell growth. Progesterone inhibitory effect on other melanoma cell lines was also reported by Fang et al., Moroni et al. and Kanda and Watanbe. So, it was hypothesized that progesterone could be protecting menstruating females in melanoma. Our further research showed that progesterone action was mediated by a specific suppression of pro-inflammatory cytokine IL-8. Several in-vivo and in-vitro studies showed the importance of IL-8 in the regulation of melanoma growth. Hence, IL-8 could be considered as a potential target for melanoma treatment.