55 A case control study of adult men and women is performed to determine the relationship of obesity to cancer. The dataindicate an increased risk for cancers of the esophagus and kidney in subjects with a body mass index above 25. Which of the following substances is most likely to contribute to the development of cancer in these subjects? (A) Adiponectin (B) Aflatoxin (C) Insulin-like growth factor (IGF-1) (D) Leptin (E) Selenium (F) Trans fats