Findings from a recent study suggest that urinary levels of bisphenol A (BPA), an organic compound used to make the polycarbonate plastic and epoxy resins present in thousands of consumer products, is an independent prognostic marker for prostate cancer (PCa).
The research also indicates that low levels of BPA exposure can cause cellular changes in both malignant and nonmalignant prostate cells.
More than 90% of the U.S. population is exposed to BPA, largely through absorption through the skin, inhalation, or ingestion from contaminated food and water, Shuk-Mei Ho, PhD, director of the Cincinnati Cancer Center of the University of Cincinnati (UC), and fellow investigators wrote in PLOS One (2014;9:e90332). As an endocrine disruptor that mimics estrogen and thyroid hormone, the compound also acts as a metabolic and immune disruptor.
Dr. Ho’s team explored the association between urinary BPA levels and PCa by assessing the urine specimens of 60 urology patients, 27 of whom had PCa. The group found that creatinine-adjusted BPA levels were higher in the men with PCa (5.74 µg/g) than in the men without (1.43 µg/g), with the difference being particularly significant in those aged 65 years and older.
The researchers also examined abnormalities in centrosomes, organelles required for proper cell division. Centrosomal abnormalities are often seen in cancer, and as Dr. Ho noted in a statement from the UC Academic Health Center, several studies have shown that centrosome amplification is a major contributor to chromosomal mutation in human tumors.
Dr. Ho and associates discovered that exposure to low doses of BPA increased the percentage of cells with centrosome amplification 2- to 8-fold.
“Our findings provide the first evidence that urinary BPA level may have prognostic value for [PCa] and that disruption of the centrosome duplication cycle by low-dose BPA is a previously unknown mechanism underlying neoplastic transformation and cancer progression in the prostate,” the authors concluded.