Cadmium is Everywhere, Promotes Breast Cancer
Exposure to low concentrations of cadmium can promote the progression of breast cancer, according to researchers at Dominican University of California, and make the disease more aggressive. This study is unique in that it focuses on prolonged rather than acute exposure to this heavy metal, which can be found nearly everywhere in the environment.
Cadmium is in the air, water, and soil
Cadmium is an extremely toxic heavy metal that has been named as “carcinogenic to humans” by the US Department of Health and Human Services and the International Agency for Research on Cancer. This substance is commonly found in industrial environments, especially areas where ore is being processed. It is also found in industrial paints and is used in the production of some types of batteries and phosphate fertilizers.
Aside from manufacturing settings, cadmium is also present in everyday products; namely, cigarette smoke and some cosmetics and jewelry. Cadmium can be released into the air from burning industrial and household waste, burning coal and oil, and vehicle exhaust.
Once cadmium is in the air, it is carried by the wind and is deposited into the soil and water. People can also be exposed to cadmium in food and water contaminated with the heavy metal.
Clearly, cadmium is everywhere, and being aware of this fact is especially critical in light of the new research. According to Maggie Louie, associate professor of biochemistry, who presented her findings at the annual meeting of the American Society for Biochemistry and Molecular Biology in San Diego, “Understanding the role that cadmium plays in the progression of breast cancer is extremely important in order to find better ways to prevent the disease from advancing.”
Estrogen activity is stimulated by the estrogen receptor. Cadmium is an endocrine disruptor, and as such it can imitate the hormone estrogen. While the normal growth of epithelial cells in the breast is modulated by circulating estrogen, cadmium can disrupt the hormone dependent pathways and thus promote cancer growth.
Previous studies have identified links between acute exposure to cadmium and activation of the estrogen receptor. In this new study, Louie and her team found that prolonged exposure to cadmium increased the ability of breast cancer cells to move and invade the outer barrier of organs and tissues, which is characteristic of the ability of cancer cells to spread.
More specifically, Louie discovered that MCF-7 cells (a human breast cancer cell line) chronically exposed to cadmium showed higher levels of a protein associated with tumor invasion and spread. Since the majority of cancer deaths are associated with cancer that has metastasized, Louie noted that “If we can prevent the tumor from spreading, we have a better chance of treating cancer.”
This latest study on cadmium adds fuel to previous concerns about the carcinogenic properties of this heavy metal. Given that cadmium is everywhere in the environment, it is important to understand its role in breast cancer, as well as make efforts to avoid exposure as much as possible.
“Chronic exposure to cadmium increases in the metastatic phenotype of breast cancer cells,” Abstract No. 7038, presented at the American Society for Biochemistry and Molecular Biology annual meeting
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