Circulating adiponectin levels in relation to melanoma: A case–control study

Abstract

Aim Melanoma, a malignancy with steadily increasing prevalence, has been associated not only with sun exposure but also with phenotypic characteristics including obesity. Adiponectin, an adipocyte secreted endogenous insulin sensitizer, has been found to play a protective role in several obesity related cancers but has not yet been studied in relation to melanoma. We investigated the association of circulating adiponectin levels with melanoma in Greece, a country with rather low incidence of the disease and high annual sunshine levels. Methods In the context of a case–control study, we studied over a 22-month period 55 patients with incident, histologically confirmed melanoma cases and 165 healthy controls matched for gender and age. Results After controlling for the possible confounding effect of education, body mass index and waist-to-hip ratio in multiple logistic regression analyses, sun sensitive skin type was significantly and positively associated with melanoma risk (OR: 2.48, 95% Confidence Interval: 1.22–5.10, p: 0.01). On the contrary, there was a sizeable, though non-significant, inverse association of serum adiponectin levels with the disease (OR: 0.75, 95% Confidence Interval: 0.52–1.10, p: 0.14). Conclusion A protective role of adiponectin in the development of melanoma cannot be excluded given the presented empirical evidence (25% reduction per one SD of adiponectin) and the direct anti-neoplastic features of the hormone. The results are intriguing enough to point to the need for further investigation.