Researchers in this study wanted to understand why breast cancers can behave so differently—even when they have similar genetic mutations. Breast cancer is not one single disease; instead, it includes many subtypes that grow and spread in different ways. The researchers focused on how two key factors—the type of normal breast cell where cancer begins (cell-of-origin) and genetic changes (oncogenes)—work together to influence cancer development.
To study this, they created a set of breast cell models using normal breast cells from healthy women. These cells were exposed to specific cancer-related genes to observe how they changed over time. The researchers then examined how these cells grew, formed tumors, responded to treatment, and developed features linked to cancer progression.
They found that the same genetic changes can lead to very different outcomes depending on the original cell type. For example, some cell types were more likely to form aggressive tumors or develop the ability to spread, while others were less affected. The study also showed that certain oncogenes increased the ability of cells to renew themselves and form diverse cell populations, which are features linked to cancer growth.
Overall, the results suggest that both the starting cell type and genetic mutations play a critical role in shaping how breast cancer develops and behaves.
