In probably the most comprehensive review to show how breast cancer develops, scientists have created a map that shows how various chemicals cause breast cancer.
The problem the researchers set out to address was the knowledge gap in the cause of breast cancer. Scientists are well aware of the various chemical triggers of breast cancer; however, when they want to determine if a chemical is harmful or not, they often do not capture the effects on the breast. This led to a comprehensive study to help regulators determine what changes in the breast lead to breast cancer and which chemicals can trigger these changes.
The researchers used ionizing radiation, a known risk factor for breast cancer, to understand the sequential precancerous changes. They also reviewed 467 studies of women who were exposed to ionizing radiation and developed breast cancer. They then created a map to show these sequential changes in the breast from radiation exposure to cancer development.
Traditionally, scientists had believed that ionizing radiation causes cancer through DNA damage. But with this new method used in the study, scientists reveal ionization also caused cancer by increasing the production of toxic substances called reactive oxygen and nitrogen species. These molecules trigger inflammation, damage DNA, and alter vital biological processes within cells.
Against this backdrop, the researchers suggest that chemicals that can trigger these changes and alterations can be regarded as a breast cancer risk factor.