Chronic Exposure to Cadmium Increases in the Metastatic Phenotype of Breast Cancer Cells

Abstract

Breast cancer is one of the most frequently diagnosed cancers among American women in the U.S. Studies suggest that environmental factors such as heavy metal exposure may contribute to development and progression of breast cancer. Cadmium has been shown to induce malignant transformation and increase the aggressive phenotype of mammary epithelial cells. The study focuses on understanding the effects of chronic cadmium exposure on breast cancer progression. Preliminary data show an increase in the ability of MCF‐7 cells to migrate and invade through the extracellular matrix with cadmium exposure. MCF‐7 cells chronically exposed to cadmium (MCF7‐CdC) express higher levels of SDF‐1, a protein associated with tumor invasion and metastasis. Additionally matrix metalloeproteinase‐9 (MMP‐9) activity was significantly higher in MCF7‐CdC cells. How SDF‐1 and MMP‐9 contribute to the aggressive phenotype of the cadmium exposed cells requires further research, and understanding their role in cadmium‐induced carcinogenesis will provide further insights to how heavy metals contribute to breast cancer progression.