MicroRNA-181a Suppresses Progestin-Stimulated Breast Cancer Cell Growth

Despite all our efforts, breast cancer remains a major public health problem threatening women’s health all around the world. The morbidity of breast cancer is rising in most countries and is going to rise further over the next 20 years. Hormone treatment is widely used and it is the most efficient method of reducing menopausal symptoms or preventing abortion and pregnancy. However, multiple studies have demonstrated that hormones, especially synthetic progesterone, remain an indisputable risk factor for breast cancer. MicroRNAs are a group of endogenous small non-coding single strand RNAs which play regulatory roles in the initiation, development, and progression of different types of cancer. Evidence from multiple sources indicates that microRNA-181a exerts anti-breast cancer effects by inducing cancer cell death and preventing tumor invasion, infiltration and metastasis, etc. Our recent studies revealed that microRNA-181a not only suppresses breast cancer MCF-7 cell growth but also abrogates progestin-provoked cell growth. In this review, several interesting aspects of hormone replacement therapy and the role of microRNA-181a during progestin treatment are discussed.