This month The American Journal of Pathology highlights the influence of the cellular microenvironment on breast cancer by promoting three articles from the current issue. These articles describe advances in our understanding of progression of breast cancer, local cells affecting tamoxifen sensitivity, and epigenetic reversion of breast cancer DNA. The three papers appear in the May issue of the AJP, with breast cancer DNA reversion highlighted on the cover.
PROGRESSION OF BREAST CANCER
Researchers have identified loss of Fiblin-2 as a marker of breast cancer progression since the protein is expressed by normal breast cells but lost in breast cancer cell lines and invasive breast tumors. As further confirmation of Fibulin-2s anti-invasion effect, reintroduction of the protein into Fibulin-2-negative breast cancer cells resulted in decreased cell migration and invasion in vitro.
Fibulin-2 is a known component of the extracellular matrix (the supportive protein structure surrounding cells) and is thought to be critical for cell migration during wound healing. However, loss of Fibulin-2 in breast cancer may lead to changes in the environment surrounding, and confining, cancer cells, thus enabling cancer cells to migrate from their original site to other locations.
Fibulin-2s potential involvement in breast cancer spread may provide prognostic implications if loss of its expression can be directly correlated with the transition from noninvasive breast cancer to recurrent and/or invasive breast cancer. Future studies will explore the exact mechanisms by which Fibulin-2 mediates its anti-invasion effect.
This work was lead by Dr. Michael A. Hollingsworth at the University of Nebraska Medical Center, Omaha, Nebraska, and supported by the Department of Defense and the National Institutes of Health.