BPA levels in men's urine may predict prostate cancer

Levels of bisphenol A in men's urine could be a marker of prostate cancer and low levels of BPA can cause changes in prostate cells, U.S. researchers say. The research, published in Plos One, said it provided the first evidence that urinary BPA levels may help predict prostate cancer and that disruption of a cell duplication cycle through exposure to low-dose BPA might cause cancer development in the prostate. BPA, an environmental pollutant, is used to make hard, clear plastic and is common in many food product containers. Principle investigator Shuk-mei Ho, director of the Cincinnati Cancer Center, and professor at the University of Cincinnati College of Medicine, said human exposure to BPA is a common occurrence and that animal studies have shown that BPA contributes to development of prostate cancer, but human data was scarce. Ho said U.S. exposure to BPA is widespread -- exceeding 90 percent in the general population -- and that absorption through the skin, inhalation and ingestion from contaminated food and water are the major kinds of exposure. The researchers assessed the Prostate-Specific Antigen of 60 urology patients using urine samples. Higher levels of BPA were found in prostate cancer patients than in non-prostate cancer patients and the difference was even more significant in patients age 65 and younger. The researchers examined prostate cells -- normal and cancerous -- using immunofluorescence, allowing them to visualize the distribution of the target molecule and look specifically at centrosomal abnormalities and growth patterns. "Exposure to low doses of BPA increased the percentage of cells with centrosome amplification two- to eight-fold," Ho said. "All of these findings revealed a previously unknown relationship between BPA exposure and prostate cancer and suggest a mechanism underlying the role of BPA in cellular transformation and disease progression. With this insight, we hope to further investigate ways we can decrease exposures to potentially cancerous-causing chemicals in every day products and substances and reduce the onset of prostate cancer in men."