Current evidence tells us that being overweight is a risk factor for breast cancer. So fat cells in the breast are bad, right? Maybe not. New research by Conway and colleagues at the University of Turku in Finland suggests it's more complicated than that. Dr Sandy Minck explains....
Insulin-like growth factor binding protein 2 (IGFBP2) and fat cells
Researchers have found that cells in the breast release a protein called insulin-like growth factor binding protein 2 (IGFBP2). They found that IGFBP2 plays a protective role to decrease cancer cell spread (also known as invasion) to surrounding tissues. They also found that healthy breast fat cells release more IGFBP2 than other types of cells in the breast.
IGFBP2 and cancer cells
The researchers found less IGFBP2 in samples with higher grades of cancer such as invasive ductal carcinoma compared to samples with lower grades of cancer like ductal carcinoma in situ and healthy samples. There was even less IGFBP2 in cells inside of the cancer compared to those at the spreading edge of the cancer. These findings support the role of IGFBP2 in decreasing cancer spread.
IGFBP2 and age
Because the risk of breast cancer increases with age, the researchers compared the amount of IGFBP2 released by fat cells across two different age groups, 18-26 and 40-45. There was much less IGFBP2 in the older age group. So, as well as the loss of fat cells that occurs as women age, the researchers think that the anti-cancer activity of fat cells might also decrease with age.
What’s this got to do with breast density and cancer risk?
Higher breast density is associated with a lower breast fat content. The researchers found that healthy breast fat cells release factors, such as IGFBP2, to decrease cancer spread. Based on this study, it's possible that the lower fat content in extremely dense breasts explains the increased breast cancer risk. In the same way, the lower levels of IGFBP2 found in older individuals may help explain why increasing age is a risk factor for breast cancer.
What next?
The researchers don’t think increasing IGFBP2 in the breast is possible, but they may be able to develop compounds to act in a similar way to IGFBP2 to help limit the spread of cancer cells.
The research findings were published in the journal Science Advances and are described in a press release from University of Turku .
Understand your breast density and be informed of the risks and screening outcomes.
Stay informed and advocate for better breast health by joining InforMD. Sign up and learn more about this movement and be part of the change.
