Developing Mammary Gland Models for Biomedical Applications.

A comprehensive understanding of the physiological functions of mammary glands and the mechanisms underlying breast diseases is crucial for promoting women's health and well-being. This review systematically summarizes the development and applications of in vitro mammary gland models, focusing on key components including cell types, hydrogel matrix, and breast-on-a-chip platforms. We begin with a detailed overview of primary mammary epithelial cells, various cell lines, organoids, and multicellular coculture systems, highlighting their respective characteristics and advantages in mimicking mammary gland physiology and pathology. Next, we examine the essential role of hydrogel matrix in providing extracellular matrix support and facilitating cellular interactions. Furthermore, recent advances in breast-on-a-chip technologies are reviewed, covering their design, fabrication, and functional capabilities that enable high-throughput drug screening and disease mechanism investigations. Finally, we explore the applications of these in vitro models in mammary gland development, breast cancer research, and drug discovery, underscoring their critical role in improving prevention and treatment strategies. By integrating these state-of-the-art technologies, this review provides researchers with a comprehensive perspective to better understand and apply in vitro mammary models in innovative studies.