Our research makes use of several strategies to investigate the mechanisms of breast cancer development. Innovative new tissue culture methods have been used extensively in these studies. We have recently identified a new type of transforming growth factor that influences the earliest steps in tumor development; this molecule is being characterized in detail. This type of molecule is produced by connective tissue cells. Its production can be modulated by several hormones, including estrogens. Interestingly, the production of this and related growth factors is distinctly different in older individuals. This observation may provide a significant clue as to why most cancer is a disease of old age
