A Robust Mammary Organoid System to Model Lactation and Involution-like Processes

Area of Science:

• Developmental Biology
• Cancer Biology
• Tissue Engineering

Background:

• The mammary gland undergoes dynamic changes during reproductive life, making its development crucial for understanding breast cancer.
• Mammary gland tumors are a leading global cancer in women, necessitating research into their origins.
• Three-dimensional (3D) organoids provide a powerful platform for studying tissue development and diseases like breast cancer.

Purpose of the Study:

• To present a straightforward 3D organoid system for studying mammary gland lactation and involution ex vivo.
• To model the cyclical processes of lactation and involution in the mammary gland.
• To offer a tool for investigating late postnatal mammary gland development and postpartum-associated breast cancer.

Main Methods:

• Utilizing primary and passaged mouse mammary organoids.
• Stimulating organoids with fibroblast growth factor 2 (FGF2) and prolactin.
• Culturing organoids in a 3D system to mimic in vivo conditions for lactation and involution.

Main Results:

• Successfully modeled three cycles of lactation and involution in mouse mammary organoids.
• Demonstrated the utility of the 3D organoid system for studying mammary gland physiology.
• Established a reproducible protocol for generating and culturing mammary organoids.

Conclusions:

• The developed 3D mammary organoid system is a valuable tool for studying mammary gland development and involution.
• This model system can advance research into breast cancer, particularly postpartum-associated forms.
• Ex vivo organoid culture offers a promising approach for investigating complex tissue dynamics and disease mechanisms.