Mimicking living breast tissue through the new Raman-based imaging tool of vibrational spectral microscopy reveals subtle changes and can could help assess a woman’s breast cancer risk. The imaging technique identifies and tracks certain molecules by measuring their vibration with a laser. It works at high speed to enable researchers to measure changes in real time in live tissue, said Ji-Xin Cheng, an associate professor of biomedical engineering and chemistry at Purdue University. The researchers used a special “3-D culture” that mimics living mammary gland tissue to show that fatty acid found in some foods influences the early precancerous stage. Unlike conventional flat cell cultures, the 3-D cultures have the round shape of milk-producing glands and behave like real tissue, said Sophie Lelièvre, an associate professor of basic medical sciences. Researchers used a new imaging technology and a special “3-D culture” that mimics living mammary gland tissue to reveal subtle changes in breast tissue. This method could potentially determine a woman’s risk of developing breast cancer and to study ways of preventing the disease. Unlike conventional cell cultures, the 3-D cultures have the round shape of milk-producing glands and behave like real tissue. (Purdue University image/Shuhua Yue) “This extremely sensitive technique shows the harmful impact of a nutrient called arachidonic acid,” Lelièvre said. “This fatty acid has been previously proposed to increase breast cancer risk, but until now there was no biological evidence of what it could do to alter breast epithelial cells.” Researchers are studying changes that take place in epithelial cells, which make up tissue and organs where 90 percent of cancers occur. These changes in the tissue are necessary for tumors to form, she explained. “By mimicking the early stage conducive to tumors and using a new imaging tool, our goal is to be able to measure this change and then take steps to prevent it,” Lelièvre said. By monitoring the same 3-D culture before and after exposure to certain risk factors, the new imaging technique allows researchers to detect subtle changes in single live cells, Cheng said. “Now there is no good way to assess risk for breast cancer,” Lelièvre said. “Assessments are mainly based on family history and genetic changes, and this only accounts for a very small percentage of women who get breast cancer. We need technology to assess the risk better and then screen for protective factors that could be used on individual patients because not everybody will be responsive to the same factors.” The researchers will continue to develop a hyperspectral imaging system capable of imaging not only a specific point in a culture, but also many locations to form a point-by-point map so that tissue polarity can be directly visualized. The research, which appeared in the February issue of Biophysical Journal, is part of the International Breast Cancer and Nutrition project launched by Purdue in October 2010 to better understand the role nutrients and other environmental factors play in breast tissue alterations and cancer development. For more information, visit: www.purdue.edu