Updated Clinical Evidence on the Role of Adipokines and Breast Cancer: A Review

Simple Summary Breast cancer is currently one of the most common types of cancer and the number one cause of cancer-related deaths in women worldwide. Despite significant advances involving cancer research in cancer biology, targeted treatments, and novel surgical approaches, breast cancer poses a constant, prominent challenge. In order to combat this reality, novel biomarkers and treatment targets are constantly on the rise. One of the known risk factors and survival predictors of breast cancer is obesity and obesity-related hormonal changes. The main effectors of said hormonal changes are a group of fatty tissue-related molecules, adipokines. Adipokines have many known and intertwined mechanisms of actions, many of which are known to enable carcinogenesis within the breast tissue. This review aims to summarize all available evidence of relationships between adipokines and the development of breast cancer, in order to emphasize their potential roles as novel biomarkers, predictive indicators, and possible future therapeutic targets of breast cancer. With the recent leaps in medicine, the landscape of our knowledge regarding adipose tissue has changed dramatically: it is now widely regarded as a fully functional endocrine organ. In addition, evidence from observational studies has linked the pathogenesis of diseases like breast cancer with adipose tissue and mainly with the adipokines that are secreted in its microenvironment, with the catalog continuously expanding. Examples include leptin, visfatin, resistin, osteopontin, and more. This review aims to encapsulate the current clinical evidence concerning major adipokines and their link with breast cancer oncogenesis. Overall, there have been numerous meta-analyses that contribute to the current clinical evidence, however more targeted larger-scale clinical studies are still expected to solidify their clinical utility in BC prognosis and reliability as follow-up markers.