Emerging roles of microRNA‐208a in cardiology and reverse cardio‐oncology

Abstract Cardiovascular diseases (CVDs) and cancer, which are the leading causes of mortality globally, have been viewed as two distinct diseases. However, the fact that cancer and CVDs may coincide has been noted by cardiologists when taking care of patients with CVDs caused by cancer chemotherapy; this entity is designated cardio‐oncology. More recently, patients with CVDs have also been found to have increased risk of cancers, termed reverse cardio‐oncology. Although reverse cardio‐oncology has been highlighted as an important disease state in recent studies, how the diseased heart affects cancer and the potential mediators of the crosstalk between CVDs and cancer are largely unknown. Here, we focus on the roles of cardiac‐specific microRNA‐208a ( miR‐208a ) in cardiac and cancer biology and explore its essential roles in reverse cardio‐oncology. Accumulating evidence has shown that within the heart, increased miR‐208a promotes myocardial injury, arrhythmia, cardiac remodeling, and dysfunction and that secreted miR‐208a in the circulation may have novel roles in promoting tumor proliferation and invasion. This review, therefore, provides insights into the novel roles of miR‐208a in reverse cardio‐oncology and strategies to prevent secondary carcinogenesis in patients with early‐ or late‐stage heart failure.