Resistin, Obesity, and Cancer

Abstract

Obesity, a major global epidemic of this century, is associated with type 2 diabetes, cardiovascular diseases, and various types of cancer. Cancer is among the leading causes of morbidity and mortality worldwide. Many adipose tissue-derived biomarkers are associated with risks of cancer. Resistin is an adipokine produced mainly by adipocytes in mice, but monocytes and macrophages in human. Resistin was initially recognized as a regulator of insulin resistance and inflammation. There has been increasing evidence suggesting an association between increased resistin levels and obesity, as well as obesity-related disorders, such as diabetes, cardiovascular diseases, and malignancies. In particular, studies have reported higher circulating resistin levels in patients with certain types of cancer including breast cancer, colorectal cancer, lung cancer, hematologic malignancies, endometrial cancer, and pancreatic cancer, but contradictory results have also been documented. Although our understandings of the causal role and the underlying mechanisms of resistin in cancer progression and metastasis remain incomplete, resistin has been found to promote proliferation, migration, and invasiveness of a number of cancer cell lines. Furthermore, as a key inflammatory biomarker and mediator of insulin resistance, resistin may indirectly mediate cancer development through its metabolic effects. In this chapter, we summarize the current findings on the pathophysiological implications of resistin in obesity and related diseases from experimental, clinical, and epidemiological perspectives in order to decipher its role in linking obesity, insulin resistance, and inflammation to cancer.